GMNN

Gene Summary

Gene:GMNN; geminin, DNA replication inhibitor
Aliases: Gem
Location:6p22.3
Summary:This gene encodes a protein that plays a critical role in cell cycle regulation. The encoded protein inhibits DNA replication by binding to DNA replication factor Cdt1, preventing the incorporation of minichromosome maintenance proteins into the pre-replication complex. The encoded protein is expressed during the S and G2 phases of the cell cycle and is degraded by the anaphase-promoting complex during the metaphase-anaphase transition. Increased expression of this gene may play a role in several malignancies including colon, rectal and breast cancer. Alternatively spliced transcript variants have been observed for this gene, and two pseudogenes of this gene are located on the short arm of chromosome 16. [provided by RefSeq, Oct 2011]
Databases:OMIM, VEGA, HGNC, Ensembl, GeneCard, Gene
Protein:geminin
HPRD
Source:NCBIAccessed: 11 August, 2015

Ontology:

What does this gene/protein do?
Show (16)

Cancer Overview

Research Indicators

Publications Per Year (1990-2015)
Graph generated 11 August 2015 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Down-Regulation
  • Phosphorylation
  • Mutation
  • DNA Replication
  • alpha Karyopherins
  • Ubiquitin-Protein Ligases
  • Single Nucleotide Polymorphism
  • MicroRNAs
  • DNA-Binding Proteins
  • Aurora Kinases
  • DNA Damage
  • Biological Models
  • Messenger RNA
  • Genes, cdc
  • Case-Control Studies
  • Geminin
  • Cell Proliferation
  • Cell Cycle
  • Chromosome 6
  • Up-Regulation
  • Breast Cancer
  • Aneuploidy
  • Cell Cycle Proteins
  • Protein-Serine-Threonine Kinases
  • Gene Expression Profiling
  • Nuclear Proteins
  • Neoplastic Cell Transformation
  • Adolescents
  • Minichromosome Maintenance Complex Component 2
  • Cancer Gene Expression Regulation
  • Tumor Markers
  • Histones
  • Liver Cancer
  • Immunohistochemistry
  • Oligonucleotide Array Sequence Analysis
  • Cohort Studies
  • Young Adult
  • MKI67
  • Mitosis
  • Restriction Fragment Length Polymorphism
  • Genomic Instability
Tag cloud generated 11 August, 2015 using data from PubMed, MeSH and CancerIndex

Specific Cancers (2)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: GMNN (cancer-related)

Kwong LN, Boland GM, Frederick DT, et al.
Co-clinical assessment identifies patterns of BRAF inhibitor resistance in melanoma.
J Clin Invest. 2015; 125(4):1459-70 [PubMed] Free Access to Full Article Related Publications
Multiple mechanisms have been described that confer BRAF inhibitor resistance to melanomas, yet the basis of this resistance remains undefined in a sizable portion of patient samples. Here, we characterized samples from a set of patients with melanoma that included individuals at baseline diagnosis, on BRAF inhibitor treatment, and with resistant tumors at both the protein and RNA levels. Using RNA and DNA sequencing, we identified known resistance-conferring mutations in 50% (6 of 12) of the resistant samples. In parallel, targeted proteomic analysis by protein array categorized the resistant samples into 3 stable groups, 2 of which were characterized by reactivation of MAPK signaling to different levels and 1 that was MAPK independent. The molecular relevance of these classifications identified in patients was supported by both mutation data and the similarity of resistance patterns that emerged during a co-clinical trial in a genetically engineered mouse (GEM) model of melanoma that recapitulates the development of BRAF inhibitor resistance. Additionally, we defined candidate biomarkers in pre- and early-treatment patient samples that have potential for predicting clinical responses. On the basis of these observations, we suggest that BRAF inhibitor-resistant melanomas can be actionably classified using protein expression patterns, even without identification of the underlying genetic alteration.

Taylor NJ, Reiner AS, Begg CB, et al.
Inherited variation at MC1R and ASIP and association with melanoma-specific survival.
Int J Cancer. 2015; 136(11):2659-67 [PubMed] Free Access to Full Article Related Publications
Melanocortin-1 receptor (MC1R) is a marker of melanoma risk in populations of European ancestry. However, MC1R effects on survival are much less studied. We investigated associations between variation at MC1R and survival in an international, population-based series of single primary melanoma patients enrolled into the Genes, Environment, and Melanoma study. MC1R genotype data was available for 2,200 participants with a first incident primary melanoma diagnosis. We estimated the association of MC1R genotypes with melanoma-specific survival (i.e., death caused by melanoma) and overall survival using COX proportional hazards modeling, adjusting for established prognostic factors for melanoma. We also conducted stratified analyses by Breslow thickness, tumor site, phenotypic index, and age. In addition, we evaluated haplotypes involving polymorphisms near the Agouti signaling protein gene (ASIP) locus for their impacts on survival. Melanoma-specific survival was inversely associated with carriage of MC1R variants in the absence of consensus alleles compared to carriage of at least one consensus allele (hazard ratio (HR) = 0.60; 95% confidence interval (CI): 0.40, 0.90). MC1R results for overall survival were consistent with no association. We did not observe any statistical evidence of heterogeneity of effect estimates in stratified analyses. We observed increased hazard of melanoma-specific death among carriers of the risk haplotype TG near the ASIP locus (HR = 1.37; 95% CI: 0.91, 2.04) when compared to carriers of the most common GG haplotype. Similar results were noted for overall survival. Upon examining the ASIP TG/TG diplotype, we observed considerably increased hazard of melanoma-specific death (HR = 5.11; 95% CI: 1.88, 13.88) compared to carriers of the most common GG/GG diplotype. Our data suggest improved melanoma-specific survival among carriers of two inherited MC1R variants.

Warrington NM, Sun T, Luo J, et al.
The cyclic AMP pathway is a sex-specific modifier of glioma risk in type I neurofibromatosis patients.
Cancer Res. 2015; 75(1):16-21 [PubMed] Article available free on PMC after 01/01/2016 Related Publications
Identifying modifiers of glioma risk in patients with type I neurofibromatosis (NF1) could help support personalized tumor surveillance, advance understanding of gliomagenesis, and potentially identify novel therapeutic targets. Here, we report genetic polymorphisms in the human adenylate cyclase gene adenylate cyclase 8 (ADCY8) that correlate with glioma risk in NF1 in a sex-specific manner, elevating risk in females while reducing risk in males. This finding extends earlier evidence of a role for cAMP in gliomagenesis based on results in a genetically engineered mouse model (Nf1 GEM). Thus, sexually dimorphic cAMP signaling might render males and females differentially sensitive to variation in cAMP levels. Using male and female Nf1 GEM, we found significant sex differences exist in cAMP regulation and in the growth-promoting effects of cAMP suppression. Overall, our results establish a sex-specific role for cAMP regulation in human gliomagenesis, specifically identifying ADCY8 as a modifier of glioma risk in NF1.

McCann MJ, Rowland IR, Roy NC
The anti-proliferative effects of enterolactone in prostate cancer cells: evidence for the role of DNA licencing genes, mi-R106b cluster expression, and PTEN dosage.
Nutrients. 2014; 6(11):4839-55 [PubMed] Article available free on PMC after 01/01/2016 Related Publications
The mammalian lignan, enterolactone, has been shown to reduce the proliferation of the earlier stages of prostate cancer at physiological concentrations in vitro. However, efficacy in the later stages of the disease occurs at concentrations difficult to achieve through dietary modification. We have therefore investigated what concentration(s) of enterolactone can restrict proliferation in multiple stages of prostate cancer using an in vitro model system of prostate disease. We determined that enterolactone at 20 μM significantly restricted the proliferation of mid and late stage models of prostate disease. These effects were strongly associated with changes in the expression of the DNA licencing genes (GMNN, CDT1, MCM2 and 7), in reduced expression of the miR-106b cluster (miR-106b, miR-93, and miR-25), and in increased expression of the PTEN tumour suppressor gene. We have shown anti-proliferative effects of enterolactone in earlier stages of prostate disease than previously reported and that these effects are mediated, in part, by microRNA-mediated regulation.

Fiorini C, Cordani M, Padroni C, et al.
Mutant p53 stimulates chemoresistance of pancreatic adenocarcinoma cells to gemcitabine.
Biochim Biophys Acta. 2015; 1853(1):89-100 [PubMed] Related Publications
Pancreatic adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths worldwide; PDAC is characterized by poor prognosis, resistance to conventional chemotherapy and high mortality rate. TP53 tumor suppressor gene is frequently mutated in PDAC, resulting in the accumulation of mutated protein with potential gain-of-function (GOF) activities, such as genomic instability, hyperproliferation and chemoresistance. The purpose of this study was to assess the relevance of the p53 status on the PDAC cells response to the standard drug gemcitabine. We also examined the potential therapeutic effect of p53-reactivating molecules to restore the mutant p53 function in GEM treated PDAC cells. We showed that gemcitabine stabilized mutant p53 protein in the nuclei and induced chemoresistance, concurrent with the mutant p53-dependent expression of Cdk1 and CCNB1 genes, resulting in a hyperproliferation effect. Despite the adverse activation of mutant p53 by gemcitabine, simultaneous treatment of PDAC cells with gemcitabine and p53-reactivating molecules (CP-31398 and RITA) reduced growth rate and induced apoptosis. This synergistic effect was observed in both wild-type and mutant p53 cell lines and was absent in p53-null cells. The combination drug treatment induced p53 phosphorylation on Ser15, apoptosis and autophagosome formation. Furthermore, pharmacological inhibition of autophagy further increased apoptosis stimulated by gemcitabine/CP-31398 treatment. Together, our results show that gemcitabine aberrantly stimulates mutant p53 activity in PDAC cells identifying key processes with potential for therapeutic targeting. Our data also support an anti-tumoral strategy based on inhibition of autophagy combined with p53 activation and standard chemotherapy for both wild-type and mutant p53 expressing PDACs.

Laurberg JR, Jensen JB, Schepeler T, et al.
High expression of GEM and EDNRA is associated with metastasis and poor outcome in patients with advanced bladder cancer.
BMC Cancer. 2014; 14:638 [PubMed] Article available free on PMC after 01/01/2016 Related Publications
BACKGROUND: The standard treatment for non-metastatic muscle-invasive bladder cancer (stages T2-T4a) is radical cystectomy with lymphadenectomy. However, patients undergoing cystectomy show metastatic spread in 25% of cases and these patients will have limited benefit from surgery. Identification of patients with high risk of lymph node metastasis will help select patients that may benefit from neoadjuvant and/or adjuvant chemotherapy.
METHODS: RNA was procured by laser micro dissection of primary bladder tumors and corresponding lymph node metastases for Affymetrix U133 Plus 2.0 Gene Chip expression profiling. A publically available dataset was used for identification of the best candidate markers, and these were validated using immunohistochemistry in an independent patient cohort of 368 patients.
RESULTS: Gene Set Enrichment Analysis showed significant enrichment for e.g. metastatic signatures in the metastasizing tumors, and a set of 12 genes significantly associated with lymph node metastasis was identified. Tumors did not cluster according to their metastatic ability when analyzing gene expression profiles using hierarchical cluster analysis. However, half (6/12) of the primary tumor clustered together with matching lymph node metastases, indicating a large degree of intra-patient similarity in these patients. Immunohistochemical analysis of 368 tumors from cystectomized patients showed high expression of GEM (P = 0.033; HR = 1.46) and EDNRA (P = 0.046; HR = 1.60) was significantly associated with decreased cancer-specific survival.
CONCLUSIONS: GEM and EDNRA were identified as promising prognostic markers for patients with advanced bladder cancer. The clinical relevance of GEM and EDNRA should be evaluated in independent prospective studies.

Thomas NE, Kricker A, Waxweiler WT, et al.
Comparison of clinicopathologic features and survival of histopathologically amelanotic and pigmented melanomas: a population-based study.
JAMA Dermatol. 2014; 150(12):1306-314 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
IMPORTANCE Previous studies have reported that histopathologically amelanotic melanoma is associated with poorer survival than pigmented melanoma; however, small numbers of amelanotic melanomas, selected populations, lack of centralized pathologic review, or no adjustment for stage limit the interpretation or generalization of results from prior studies.OBJECTIVE To compare melanoma-specific survival between patients with histopathologically amelanotic and those with pigmented melanoma in a large international population-based study.DESIGN, SETTING, AND PARTICIPANTS Survival analysis with a median follow-up of 7.6 years.The study population comprised 2995 patients with 3486 invasive primary melanomas centrally scored for histologic pigmentation from the Genes, Environment, and Melanoma(GEM) Study, which enrolled incident cases of melanoma diagnosed in 1998 through 2003 from international population-based cancer registries.MAIN OUTCOMES AND MEASURES Clinicopathologic predictors and melanoma-specific survival of histologically amelanotic and pigmented melanoma were compared using generalized estimating equations and Cox regression models, respectively.RESULTS Of 3467 melanomas, 275 (8%) were histopathologically amelanotic. Female sex,nodular and unclassified or other histologic subtypes, increased Breslow thickness, presence of mitoses, severe solar elastosis, and lack of a coexisting nevus were independently associated with amelanotic melanoma (each P < .05). Amelanotic melanoma was generally ofa higher American Joint Committee on Cancer (AJCC) tumor stage at diagnosis (odds ratios[ORs] [95%CIs] between 2.9 [1.8-4.6] and 11.1 [5.8-21.2] for tumor stages between T1b and T3b and ORs [95%CIs] of 24.6 [13.6-44.4] for T4a and 29.1 [15.5-54.9] for T4b relative to T1a;P value for trend, <.001) than pigmented melanoma. Hazard of death from melanoma was higher for amelanotic than for pigmented melanoma (hazard ratio [HR], 2.0; 95%CI, 1.4-3.0)(P < .001), adjusted for age, sex, anatomic site, and study design variables, but survival did not differ once AJCC tumor stage was also taken into account (HR, 0.8; 95%CI, 0.5-1.2)(P = .36).CONCLUSIONS AND RELEVANCE At the population level, survival after diagnosis of amelanotic melanoma is poorer than after pigmented melanoma because of its more advanced stage at diagnosis. It is probable that amelanotic melanomas present at more advanced tumor stages because they are difficult to diagnose. The association of amelanotic melanoma with presence of mitoses independently of Breslow thickness and other clinicopathologic characteristics suggests that amelanotic melanomas might also grow faster than pigmented melanomas. New strategies for early diagnosis and investigation of the biological properties of amelanotic melanoma are warranted.

McNeill RS, Schmid RS, Bash RE, et al.
Modeling astrocytoma pathogenesis in vitro and in vivo using cortical astrocytes or neural stem cells from conditional, genetically engineered mice.
J Vis Exp. 2014; (90):e51763 [PubMed] Related Publications
Current astrocytoma models are limited in their ability to define the roles of oncogenic mutations in specific brain cell types during disease pathogenesis and their utility for preclinical drug development. In order to design a better model system for these applications, phenotypically wild-type cortical astrocytes and neural stem cells (NSC) from conditional, genetically engineered mice (GEM) that harbor various combinations of floxed oncogenic alleles were harvested and grown in culture. Genetic recombination was induced in vitro using adenoviral Cre-mediated recombination, resulting in expression of mutated oncogenes and deletion of tumor suppressor genes. The phenotypic consequences of these mutations were defined by measuring proliferation, transformation, and drug response in vitro. Orthotopic allograft models, whereby transformed cells are stereotactically injected into the brains of immune-competent, syngeneic littermates, were developed to define the role of oncogenic mutations and cell type on tumorigenesis in vivo. Unlike most established human glioblastoma cell line xenografts, injection of transformed GEM-derived cortical astrocytes into the brains of immune-competent littermates produced astrocytomas, including the most aggressive subtype, glioblastoma, that recapitulated the histopathological hallmarks of human astrocytomas, including diffuse invasion of normal brain parenchyma. Bioluminescence imaging of orthotopic allografts from transformed astrocytes engineered to express luciferase was utilized to monitor in vivo tumor growth over time. Thus, astrocytoma models using astrocytes and NSC harvested from GEM with conditional oncogenic alleles provide an integrated system to study the genetics and cell biology of astrocytoma pathogenesis in vitro and in vivo and may be useful in preclinical drug development for these devastating diseases.

Toren A, Reichardt JK, Andalibi A, et al.
Novel age-dependent targets in vestibular schwannomas.
Hum Genomics. 2014; 8:10 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
BACKGROUND: Schwannomas are the most common neurofibromatosis type 2 (NF2)-associated tumors with significant phenotypic heterogeneity in patients. The most severe subtype has an early and rapid progression and the mild type has a later onset and a less aggressive course. The aim of this study was to elucidate the underlying molecular differences between these groups. We compared the gene expression pattern between patients with early to late age of onset.
RESULTS: A gene signature of 21 genes was constructed to differentiate between early-onset and late-onset patients. We confirmed these results by real-time PCR for SNF1LK2, NGFRAP1L1 (BEX 5), GMNN, and EPHA2.
CONCLUSION: Genes identified here may be additional aberrations in merlin-depleted cells that govern the disease onset. A significant number of these genes have been suggested as having a role in carcinogenesis and are used as biomarkers for prognosis in several other cancers. The role of these genes in NF2 carcinogenesis and their potential as biomarkers or drug target are worthwhile exploring.

Kamada M, Akiyoshi K, Akiyama N, et al.
Cholangiocarcinoma cell line TK may be useful for the pharmacokinetic study of the chemotherapeutic agent gemcitabine.
Oncol Rep. 2014; 32(2):829-34 [PubMed] Related Publications
Cholangiocarcinoma is a disease with a poor prognosis. A human cholangiocarcinoma cell line, TK, was previously established to enable further understanding of the disease. We conducted this investigation to determine whether or not the TK line is useful for pharmacokinetic study of the chemotherapeutic agent gemcitabine (GEM). Along with the BXPC3 human pancreatic adenocarcinoma cell line, the sensitivity to and effects on the TK cell line of GEM were compared. The influence of deoxycytidine kinase (dCK) transduction was also comparatively investigated. The effects of GEM in terms of drug sensitivity of the TK cell line, cell cycle and levels of transcripts of key enzymes were comparable to the BXPC3 cell line. Responses to the drug were similar in both cell lines. In contrast to pancreatic carcinoma, cell lines for research on cholangiocarcinoma have been limited. This study suggests the application of the TK cell line to the pharmacokinetic study of the chemosensitization of therapeutic drugs, such as GEM.

Szabova L, Bupp S, Kamal M, et al.
Pathway-specific engineered mouse allograft models functionally recapitulate human serous epithelial ovarian cancer.
PLoS One. 2014; 9(4):e95649 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
The high mortality rate from ovarian cancers can be attributed to late-stage diagnosis and lack of effective treatment. Despite enormous effort to develop better targeted therapies, platinum-based chemotherapy still remains the standard of care for ovarian cancer patients, and resistance occurs at a high rate. One of the rate limiting factors for translation of new drug discoveries into clinical treatments has been the lack of suitable preclinical cancer models with high predictive value. We previously generated genetically engineered mouse (GEM) models based on perturbation of Tp53 and Rb with or without Brca1 or Brca2 that develop serous epithelial ovarian cancer (SEOC) closely resembling the human disease on histologic and molecular levels. Here, we describe an adaptation of these GEM models to orthotopic allografts that uniformly develop tumors with short latency and are ideally suited for routine preclinical studies. Ovarian tumors deficient in Brca1 respond to treatment with cisplatin and olaparib, a PARP inhibitor, whereas Brca1-wild type tumors are non-responsive to treatment, recapitulating the relative sensitivities observed in patients. These mouse models provide the opportunity for evaluation of effective therapeutics, including prediction of differential responses in Brca1-wild type and Brca1-deficient tumors and development of relevant biomarkers.

Jiang Q, Yu YC, Ding XJ, et al.
Bioinformatics analysis reveals significant genes and pathways to target for oral squamous cell carcinoma.
Asian Pac J Cancer Prev. 2014; 15(5):2273-8 [PubMed] Related Publications
PURPOSE: The purpose of our study was to explore the molecular mechanisms in the process of oral squamous cells carcinoma (OSCC) development.
METHOD: We downloaded the affymetrix microarray data GSE31853 and identified differentially expressed genes (DEGs) between OSCC and normal tissues. Then Gene Ontology (GO) and Protein-Protein interaction (PPI) networks analysis was conducted to investigate the DEGs at the function level.
RESULTS: A total 372 DEGs with logFC| >1 and P value < 0.05 were obtained , including NNMT, BAX, MMP9 and VEGF. The enriched GO terms mainly were associated with the nucleoplasm, response to DNA damage stimuli and DNA repair. PPI network analysis indicated that GMNN and TSPO were significant hub proteins and steroid biosynthesis and synthesis and degradation of ketone bodies were significantly dysregulated pathways.
CONCLUSION: It is concluded that the genes and pathways identified in our work may play critical roles in OSCC development. Our data provides a comprehensive perspective to understand mechanisms underlying OSCC and the significant genes (proteins) and pathways may be targets for therapy in the future.

Yang C, Xu M, Shen HJ, et al.
Potential biomarkers for sensitivity of gallbladder cancer cells to gemcitabine.
Int J Clin Exp Pathol. 2014; 7(2):521-8 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
Gemcitabine (Gem)-based chemotherapies are the main therapeutic regimens for patients with unresectable advanced or metastatic gallbladder cancer (GBC). However, the modest ORR and mild benefit on survival demonstrates the need for finding biomarkers for sensitivity to Gem and hence improving the therapy. In present work, two GBC cell lines with vast difference in sensitivity to Gem were subjected to DNA microarray analysis. Dramatic expression difference was found in protein kinase A signaling, P2Y purigenic receptor signaling, ErbB signaling and p70S6K signaling. Predicted low expression of KRAS and inactivation of AKT/ERK signaling in Gem-resistant GBC cells was validated by quantitative PCR and immunoblotting, respectively. However, p70S6K, p38MAPK and NF-κB signaling was probably activated in Gem-resistant GBC cells, which deserves further investigation in more GBC cell lines and tissues. Our work provides potential pathway signatures for Gem sensitivity of GBC patients.

Zeekpudsa P, Kukongviriyapan V, Senggunprai L, et al.
Suppression of NAD(P)H-quinone oxidoreductase 1 enhanced the susceptibility of cholangiocarcinoma cells to chemotherapeutic agents.
J Exp Clin Cancer Res. 2014; 33:11 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
BACKGROUND: Cholangiocarcinoma (CCA) is highly resistant to most of the known chemotherapeutic treatments. NAD(P)H-quinone oxidoreductase 1 (NQO1) is an antioxidant/detoxifying enzyme recently recognized as an important contributor to chemoresistance in some human cancers. However, the contribution of NQO1 to chemotherapy resistance in CCA is unknown.
METHODS: Two CCA cell lines, KKU-100 and KKU-M214, with high and low NQO1 expression levels, respectively, were used to evaluate the sensitivity to chemotherapeutic agents; 5-fluorouracil (5-FU), doxorubicin (Doxo), and gemcitabine (Gem). NQO1 and/or p53 expression in KKU-100 cells were knocked down by siRNA. NQO1 was over-expressed in KKU-M214 cells by transfection with pCMV6-XL5-NQO1 expression vector. CCA cells with modulated NQO1 and/or p53 expression were treated with chemotherapeutic agents, and the cytotoxicity was assessed by SRB assay. The mechanism of enhanced chemosensitivity was evaluated by Western blot analysis.
RESULTS: When NQO1 was knocked down, KKU-100 cells became more susceptible to all chemotherapeutic agents. Conversely, with over-expression of NQO1 made KKU-M214 cells more resistant to chemotherapeutic agents. Western blot analysis suggested that enhanced chemosensitivity was probably due to the activation of p53-mediated cell death. Enhanced susceptibility to chemotherapeutic agents by NQO1 silencing was abolished by knockdown of p53.
CONCLUSIONS: These results suggest that inhibition of NQO1 could enhance the susceptibility of CCA to an array of chemotherapeutic agents.

Cho H, Herzka T, Zheng W, et al.
RapidCaP, a novel GEM model for metastatic prostate cancer analysis and therapy, reveals myc as a driver of Pten-mutant metastasis.
Cancer Discov. 2014; 4(3):318-33 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
Genetically engineered mouse (GEM) models are a pillar of functional cancer research. Here, we developed RapidCaP, a GEM modeling system that uses surgical injection for viral gene delivery to the prostate. We show that in Pten deficiency, loss of p53 suffices to trigger metastasis to distant sites at greater than 50% penetrance by four months, consistent with results from human prostate cancer genome analysis. Live bioluminescence tracking showed that endogenous primary and metastatic disease responds to castration before developing lethal castration resistance. To our surprise, the resulting lesions showed no activation of Akt but activation of the Myc oncogene. Using RapidCaP, we find that Myc drives local prostate metastasis and is critical for maintenance of metastasis, as shown by using the Brd4 inhibitor JQ1. Taken together, our data suggest that a "MYC-switch" away from AKT forms a critical and druggable event in PTEN-mutant prostate cancer metastasis and castration resistance.

Berwick M, MacArthur J, Orlow I, et al.
MITF E318K's effect on melanoma risk independent of, but modified by, other risk factors.
Pigment Cell Melanoma Res. 2014; 27(3):485-8 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
A rare germline variant in the microphthalmia-associated transcription factor (MITF) gene, E318K, has been reported as associated with melanoma. We confirmed its independent association with melanoma [odds ratio (OR) 1.7, 95% confidence interval (CI) = 1.1, 2.7, P = 0.03]; adjusted for age, sex, center, age × sex interaction, pigmentation characteristics, family history of melanoma, and nevus density). In stratified analyses, carriage of MITF E318K was associated with melanoma more strongly in people with dark hair than fair hair (P for interaction, 0.03) and in those with no moles than some or many moles (P for interaction, <0.01). There was no evidence of interaction between MC1R 'red hair variants' and MITF E318K. Moreover, risk of melanoma among carriers with 'low risk' phenotypes was as great or greater than among those with 'at risk' phenotypes with few exceptions.

Diggs-Andrews KA, Brown JA, Gianino SM, et al.
Sex Is a major determinant of neuronal dysfunction in neurofibromatosis type 1.
Ann Neurol. 2014; 75(2):309-16 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
OBJECTIVE: Children with neurofibromatosis-1 (NF1) are at risk for developing numerous nervous system abnormalities, including cognitive problems and brain tumors (optic pathway glioma). Currently, there are few prognostic factors that predict clinical manifestations or outcomes in patients, even in families with an identical NF1 gene mutation. In this study, we leveraged Nf1 genetically engineered mice (GEM) to define the potential role of sex as a clinically relevant modifier of NF1-associated neuronal dysfunction.
METHODS: Deidentified clinical data were analyzed to determine the impact of sex on optic glioma-associated visual decline in children with NF1. In addition, Nf1 GEM were employed as experimental platforms to investigate sexually dimorphic differences in learning/memory, visual acuity, retinal ganglion cell (RGC) death, and Nf1 protein (neurofibromin)-regulated signaling pathway function (Ras activity, cyclic adenosine monophosphate [cAMP], and dopamine levels).
RESULTS: Female patients with NF1-associated optic glioma were twice as likely to undergo brain magnetic resonance imaging for visual symptoms and 3× more likely to require treatment for visual decline than their male counterparts. As such, only female Nf1 GEM exhibited a decrement in optic glioma-associated visual acuity, shorter RGC axons, and attenuated cAMP levels. In contrast, only male Nf1 GEM showed spatial learning/memory deficits, increased Ras activity, and reduced dopamine levels.
INTERPRETATION: Collectively, these observations establish sex as a major prognostic factor underlying neuronal dysfunction in NF1, and suggest that sex should be considered when interpreting future preclinical and clinical study results.

Du X, Zhao YP, Zhang TP, et al.
Alteration of the intrinsic apoptosis pathway is involved in Notch-induced chemoresistance to gemcitabine in pancreatic cancer.
Arch Med Res. 2014; 45(1):15-20 [PubMed] Related Publications
BACKGROUND AND AIMS: Chemoresistance is a major challenge in pancreatic cancer (PC) treatment. Limited data have shown that members of the Notch signaling pathway are involved in resistance to gemcitabine (GEM) in PC. However, further evidence is needed and the underlying mechanisms remain to be elucidated. The current study aims to investigate the role of alterations of the intrinsic apoptosis pathway in Notch-induced GEM resistance of PC.
METHODS: The Notch signaling pathway was inhibited or activated in three PC cell lines (AsPC-1, BxPC-3, and MIA PaCa-2) by γ-secretase inhibition and Notch intracellular domain (NICD) overexpression, respectively. Subsequent analyses included inhibition rates of cell proliferation by GEM, cell apoptosis, and expression of proteins involved in the intrinsic apoptosis pathway.
RESULTS: Hes-1 expression was significantly elevated after GEM treatment, indicating Notch activation. Inhibition of the Notch signaling pathway by DAPT, a γ-secretase inhibitor, resulted in a significant increase of the inhibition rates by GEM in all PC cell lines. In addition, there was more frequent apoptosis, higher caspase-3 activity, up-regulation of Bax, and down-regulation of Bcl-2 and Bcl-xL. Conversely, transient transfection of NICD, which enhances the activity of the Notch signaling, caused a remarkable decrease of the chemosensitivity to GEM.
CONCLUSIONS: An alteration of the intrinsic apoptosis pathway is involved in Notch-induced chemoresistance to GEM in PC cells.

Rodriguez E, Mannion L, D'Santos P, et al.
Versatile and enhanced tumour modelling in mice via somatic cell transduction.
J Pathol. 2014; 232(4):449-57 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
Genetically engineered mouse (GEM) models of cancer currently comprise the most accurate way to experimentally recapitulate the human disease in the laboratory. Given recent advances in genomics and genetic screens, however, as well as an increasing urgency for the translation of effective preclinical treatments into the clinic, there is a pressing need to make these models easier and more efficient to work with. Accordingly, we have developed a versatile lentivirus-based approach to induce tumours from somatic cells of GEMs, add or subtract gene expression and render the tumours imageable from a simple breeding stock. The vectors deliver a tamoxifen-inducible and self-inactivating Cre recombinase, conditional bioluminescent and fluorescent proteins and an shRNA component. Following the transduction of somatic cells, tumours are initiated by Cre-mediated recombination of the inherited floxed alleles. Self-inactivation of Cre expression switches on the expression of luciferase, thereby rendering the recombined cells and resulting tumours bioluminescent. We demonstrate proof of concept of this approach by inducing bioluminescent lung tumours in conditional Kras and p53 mice. We also show that a variant vector expressing shRNA alters tumour growth dynamics and the histological grade associated with the inherited genotype. This approach comprises a versatile means to induce imageable and spontaneous tumour burden in mice. The vectors can be readily customized at the bench to modify reporter readout or tumour phenotype without additional transgenic strain development or breeding. They should also be useful for inducing imageable tumours in organs other than the lung, provided that the inherited conditional genotype is sufficiently penetrant.

Vuong K, McGeechan K, Armstrong BK, et al.
Occupational sun exposure and risk of melanoma according to anatomical site.
Int J Cancer. 2014; 134(11):2735-41 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
Although sunburn and intermittent sun exposures are associated with increased melanoma risk, most studies have found null or inverse associations between occupational (more continuous pattern) sun exposure and melanoma risk. The association of melanoma with occupational sun exposure may differ according to anatomical site, with some studies finding a positive association with melanoma on the head and neck. We examined the association between occupational sun exposure (self-reported weekday sun exposure) and melanoma risk according to anatomical site, using data from two multicentre population-based case-control studies: the Australian Melanoma Family Study (588 cases, 472 controls) and the Genes, Environment and Melanoma study (GEM; 1079 cases, 2,181 controls). Unconditional logistic regression was used to estimate odds ratios (OR) and their 95% confidence intervals, adjusting for potential confounders. Occupational sun exposure was not positively associated with melanoma risk overall or at different body sites in both studies. The GEM study found inverse associations between occupational sun exposure and melanoma on the head and neck [OR for highest vs. lowest quartile: 0.56, 95% confidence intervals (CI) 0.36-0.86, ptrend 0.02], and between the proportion of total sun exposure occurring on weekdays and melanoma on the upper limbs (OR for highest vs. lowest quartile: 0.66, 95% CI 0.42-1.02, ptrend 0.03). Our results suggest that occupational sun exposure does not increase risk of melanoma, even of melanomas situated on the head and neck. This finding seemed not to be due to negative confounding of occupational sun exposure by weekend sun.

Tai J, Cheung SS, Ou D, et al.
Antiproliferation activity of Devil's club (Oplopanax horridus) and anticancer agents on human pancreatic cancer multicellular spheroids.
Phytomedicine. 2014; 21(4):506-14 [PubMed] Related Publications
Devil's club (DC, Oplopanax horridus) is an important medicinal herb of the Pacific Northwest which has significant antiproliferation activity against a variety of human tumor cell lines in vitro. This study compared the antiproliferation activity of DC extract alone, and in combination with chemotherapeutic agents gemcitabine (GEM), cisplatin (CDDP), and paclitaxel (PTX) on human pancreatic cancer PANC-1 3D spheroids and 2D monolayer cells. 3D tumor spheroids were prepared with a rotary cell culture system. PANC-1 3D spheroids were significantly more resistant to killing by DC extract, GEM and PTX compared to 2D cells, with IC50 levels closer to that observed in vivo. DC extract significantly enhanced the antiproliferation activity of CDDP and GEM at some concentrations. The bioactive compound identified as a polyacetylene showed strong antiproliferation activity against PANC-1 2D cells and 3D spheroids with IC50 at 0.73±0.04 and 3.15±0.16μM, respectively. 3D spheroids and 2D cells differentially expressed a number of apoptosis related genes. Cell cycle analysis showed that the proportion of cells in S phase was increased and in G2/M phase reduced in 3D spheroids compared to 2D cells. DC extract can potentially be used to enhance the activity of chemotherapeutic agents against pancreatic cancer cells. Use of 3D spheroid model for screening of natural products can potentially increase the efficiency in discovering in vivo bioactive compounds.

Wei CH, Gorgan TR, Elashoff DA, et al.
A meta-analysis of gemcitabine biomarkers in patients with pancreaticobiliary cancers.
Pancreas. 2013; 42(8):1303-10 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
OBJECTIVES: The objective of this study was to summarize all clinical studies evaluating the prognostic role of gemcitabine (GEM) metabolic genes in pancreaticobiliary (PB) cancer patients receiving GEM therapy in the neoadjuvant, adjuvant, or palliative settings.
METHODS: Meta-analyses were performed to calculate the pooled hazard ratios for each gene by each clinical outcome (overall survival [OS], disease-free survival [DFS], and progression-free survival) using a random-effects approach.
RESULTS: The search strategy identified 16 eligible studies, composed of 632 PB patients total, with moderate quality. Compared with low expression, pooled hazard ratios for OS of hENT1, dCK, RRM1, RRM2, and DPD were 0.37 (95% confidence interval [CI], 0.28-0.47), 0.40 (95% CI, 0.20-0.80), 2.21 (95% CI, 1.12-4.36), 2.13 (95% CI, 1.00-4.52), and 1.91 (95% CI, 1.16-3.17), respectively. A similar trend was observed for each of these biomarkers in DFS and progression-free survival prognostication. Subgroup analyses for hENT1 showed a comparable survival correlation in the adjuvant and palliative settings.
CONCLUSIONS: High expression of hENT1 in PB cancer patients receiving GEM-based adjuvant therapy is associated with improved OS and DFS and may be the best examined prognostic marker to date. Evidence for other biomarkers is limited by a small number of publications investigating these markers.

Okamoto K, Miyoshi K, Murawaki Y
miR-29b, miR-205 and miR-221 enhance chemosensitivity to gemcitabine in HuH28 human cholangiocarcinoma cells.
PLoS One. 2013; 8(10):e77623 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
BACKGROUND AND AIMS: Cholangiocarcinoma (CCA) is highly resistant to chemotherapy, including gemcitabine (Gem) treatment. MicroRNAs (miRNAs) are endogenous, non-coding, short RNAs that can regulate multiple genes expression. Some miRNAs play important roles in the chemosensitivity of tumors. Here, we examined the relationship between miRNA expression and the sensitivity of CCA cells to Gem.
METHODS: Microarray analysis was used to determine the miRNA expression profiles of two CCA cell lines, HuH28 and HuCCT1. To determine the effect of candidate miRNAs on Gem sensitivity, expression of each candidate miRNA was modified via either transfection of a miRNA mimic or transfection of an anti-oligonucleotide. Ontology-based programs were used to identify potential target genes of candidate miRNAs that were confirmed to affect the Gem sensitivity of CCA cells.
RESULTS: HuCCT1 cells were more sensitive to Gem than were HuH28 cells, and 18 miRNAs were differentially expressed whose ratios over ± 2log2 between HuH28 and HuCCT1. Among these 18 miRNAs, ectopic overexpression of each of three downregulated miRNAs in HuH28 (miR-29b, miR-205, miR-221) restored Gem sensitivity to HuH28. Suppression of one upregulated miRNA in HuH28, miR-125a-5p, inhibited HuH28 cell proliferation independently to Gem treatment. Selective siRNA-mediated downregulation of either of two software-predicted targets, PIK3R1 (target of miR-29b and miR-221) or MMP-2 (target of miR-29b), also conferred Gem sensitivity to HuH28.
CONCLUSIONS: miRNA expression profiling was used to identify key miRNAs that regulate Gem sensitivity in CCA cells, and software that predicts miRNA targets was used to identify promising target genes for anti-tumor therapies.

Thomas NE, Busam KJ, From L, et al.
Tumor-infiltrating lymphocyte grade in primary melanomas is independently associated with melanoma-specific survival in the population-based genes, environment and melanoma study.
J Clin Oncol. 2013; 31(33):4252-9 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
PURPOSE: Although most hospital-based studies suggest more favorable survival with tumor-infiltrating lymphocytes (TILs) present in primary melanomas, it is uncertain whether TILs provide prognostic information beyond existing melanoma staging definitions. We addressed the issue in an international population-based study of patients with single and multiple primary melanomas.
PATIENTS AND METHODS: On the basis of the Genes, Environment and Melanoma (GEM) study, we conducted follow-up of 2,845 patients diagnosed from 1998 to 2003 with 3,330 invasive primary melanomas centrally reviewed for TIL grade (absent, nonbrisk, or brisk). The odds of TIL grades associated with clinicopathologic features and survival by TIL grade were examined.
RESULTS: Independent predictors (P < .05) for nonbrisk TIL grade were site, histologic subtype, and Breslow thickness, and for brisk TIL grade, they were age, site, Breslow thickness, and radial growth phase. Nonbrisk and brisk TIL grades were each associated with lower American Joint Committee on Cancer (AJCC) tumor stage compared with TIL absence (P(trend) < .001). Death as a result of melanoma was 30% less with nonbrisk TIL grade (hazard ratio [HR], 0.7; 95% CI, 0.5 to 1.0) and 50% less with brisk TIL grade (HR, 0.5; 95% CI, 0.3 to 0.9) relative to TIL absence, adjusted for age, sex, site, and AJCC tumor stage.
CONCLUSION: At the population level, higher TIL grade of primary melanoma is associated with a lower risk of death as a result of melanoma independently of tumor characteristics currently used for AJCC tumor stage. We conclude that TIL grade deserves further prospective investigation to determine whether it should be included in future AJCC staging revisions.

Martinez-Lopez J, Fernández-Redondo E, García-Sánz R, et al.
Clinical applicability and prognostic significance of molecular response assessed by fluorescent-PCR of immunoglobulin genes in multiple myeloma. Results from a GEM/PETHEMA study.
Br J Haematol. 2013; 163(5):581-9 [PubMed] Related Publications
Minimal residual disease monitoring is becoming increasingly important in multiple myeloma (MM), but multiparameter flow cytometry (MFC) and allele-specific oligonucleotide polymerase chain reaction (ASO-PCR) techniques are not routinely available. This study investigated the prognostic influence of achieving molecular response assessed by fluorescent-PCR (F-PCR) in 130 newly diagnosed MM patients from Grupo Español Multidisciplinar de Melanoma (GEM)2000/GEM05 trials (NCT00560053, NCT00443235, NCT00464217) who achieved almost very good partial response after induction therapy. As a reference, we used the results observed with simultaneous MFC. F-PCR at diagnosis was performed on DNA using three different multiplex PCRs: IGH D-J, IGK V-J and KDE rearrangements. The applicability of F-PCR was 91·5%. After induction therapy, 64 patients achieved molecular response and 66 non-molecular response; median progression-free survival (PFS) was 61 versus 36 months, respectively (P = 0·001). Median overall survival (OS) was not reached (NR) in molecular response patients (5-year survival: 75%) versus 66 months in the non-molecular response group (P = 0·03). The corresponding PFS and OS values for patients with immunophenotypic versus non-immunophenotypic response were 67 versus 42 months (P = 0·005) and NR (5-year survival: 95%) versus 69 months (P = 0·004), respectively. F-PCR analysis is a rapid, affordable, and easily performable technique that, in some circumstances, may be a valid approach for minimal residual disease investigations in MM.

Wang J, Jia R, Zhang Y, et al.
The role of Bax and Bcl-2 in gemcitabine-mediated cytotoxicity in uveal melanoma cells.
Tumour Biol. 2014; 35(2):1169-75 [PubMed] Related Publications
Gemcitabine (GEM), a new cytotoxic agent, was shown to be effective against uveal melanoma (UM) which is noted for its resistance to chemotherapy. In this study, we found the different sensitivities to GEM in UM cell lines and identified apoptotic cell death as the cause of GEM cytotoxicity. Both UM cell lines showed an increase in Bax protein levels and activation of cleaved Caspase 3. Additionally, SP6.5 cells showed a gradual increase in Bcl-2 expression over time, whereas VUP cells showed almost none. After interfering in the expression of Bcl-2, the sensitivity to GEM was obviously enhanced in SP6.5 cells. These results suggest that an increase in Bax plays a crucial role in apoptotic cell death induced by GEM in the absence of p53. Moreover, inhibition of Bcl-2 expression can efficiently enhance the cytotoxic effect of, and sensitivity to, GEM in UM cells.

Hefti MM, Hu R, Knoblauch NW, et al.
Estrogen receptor negative/progesterone receptor positive breast cancer is not a reproducible subtype.
Breast Cancer Res. 2013; 15(4):R68 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
INTRODUCTION: Estrogen receptor (ER) and progesterone receptor (PR) testing are performed in the evaluation of breast cancer. While the clinical utility of ER as a predictive biomarker to identify patients likely to benefit from hormonal therapy is well-established, the added value of PR is less well-defined. The primary goals of our study were to assess the distribution, inter-assay reproducibility, and prognostic significance of breast cancer subtypes defined by patterns of ER and PR expression.
METHODS: We integrated gene expression microarray (GEM) and clinico-pathologic data from 20 published studies to determine the frequency (n = 4,111) and inter-assay reproducibility (n = 1,752) of ER/PR subtypes (ER+/PR+, ER+/PR-, ER-/PR-, ER-/PR+). To extend our findings, we utilized a cohort of patients from the Nurses' Health Study (NHS) with ER/PR data recorded in the medical record and assessed on tissue microarrays (n = 2,011). In both datasets, we assessed the association of ER and PR expression with survival.
RESULTS: In a genome-wide analysis, progesterone receptor was among the least variable genes in ER- breast cancer. The ER-/PR+ subtype was rare (approximately 1 to 4%) and showed no significant reproducibility (Kappa = 0.02 and 0.06, in the GEM and NHS datasets, respectively). The vast majority of patients classified as ER-/PR+ in the medical record (97% and 94%, in the GEM and NHS datasets) were re-classified by a second method. In the GEM dataset (n = 2,731), progesterone receptor mRNA expression was associated with prognosis in ER+ breast cancer (adjusted P <0.001), but not in ER- breast cancer (adjusted P = 0.21). PR protein expression did not contribute significant prognostic information to multivariate models considering ER and other standard clinico-pathologic features in the GEM or NHS datasets.
CONCLUSION: ER-/PR+ breast cancer is not a reproducible subtype. PR expression is not associated with prognosis in ER- breast cancer, and PR does not contribute significant independent prognostic information to multivariate models considering ER and other standard clinico-pathologic factors. Given that PR provides no clinically actionable information in ER+ breast cancer, these findings question the utility of routine PR testing in breast cancer.

Nagano H, Tomimaru Y, Eguchi H, et al.
MicroRNA-29a induces resistance to gemcitabine through the Wnt/β-catenin signaling pathway in pancreatic cancer cells.
Int J Oncol. 2013; 43(4):1066-72 [PubMed] Related Publications
Although we studied previously the mechanisms of resistance of pancreatic cancer cells to gemcitabine (GEM), prediction of the response to GEM remains unsatisfactory. The aim of this study was to investigate the relationship between miR-29a expression and the response to GEM in pancreatic cancer cells. Changes in the growth-inhibitory effect of pancreatic cancer cells (MIAPaCa-2, PSN-1, BxPC-3 and Panc-1) to GEM were examined after overexpression or suppression of miR-29a. We also examined the effect of miR-29a on the Wnt/β-catenin signaling pathway and investigated whether the altered growth-inhibitory effect by miR-29a suppression was weakened after the addition of Wnt3a, a Wnt/β-catenin signaling activator. MIAPaCa-2 and PSN-1 cells transfected with anti-miR-29a showed significantly lower resistance to GEM. In the anti-miR-29a-transfected cells, GEM induced significantly larger numbers of apoptotic cells and S phase accumulation compared to control cells, demonstrated by Annexin V assay and flow cytometric analysis of the cell cycle, respectively. The transfected cells showed overexpression of putative target molecules including Dkk1, Kremen2 and sFRP2 and lower activation of the Wnt/β-catenin signaling pathway. The addition of Wnt3a weakened the augmented growth-inhibitory effect of anti-miR-29a transfection. Our findings suggest that miR-29a expression correlates significantly with the growth-inhibitory effect of GEM and that activation of the Wnt/β-catenin signaling pathway mediated the miR-29a-induced resistance to GEM in pancreatic cancer cell lines.

Kricker A, Armstrong BK, Goumas C, et al.
Survival for patients with single and multiple primary melanomas: the genes, environment, and melanoma study.
JAMA Dermatol. 2013; 149(8):921-7 [PubMed] Article available free on PMC after 01/12/2015 Related Publications
IMPORTANCE: Little is known about survival after a diagnosis of a second or higher-order (multiple) primary melanoma, and no study has explored survival in a population-based sample that included patients with single primary melanomas (SPMs) and multiple primary melanomas (MPMs) of any stage. Because people with a first primary melanoma are known to have an increased risk of being diagnosed with another, evidence for prognosis is needed.
OBJECTIVE: To determine whether survival after diagnosis was better in patients with MPMs than with SPMs, as suggested in a recent study. DESIGN Survival analysis with median follow-up of 7.6 (range, 0.4-10.6) years.
SETTING: The Genes, Environment, and Melanoma Study enrolled incident cases of melanoma from population-based cancer registries in Australia, Canada, Italy, and the United States. Multiple primary melanomas were ascertained during a longer period than SPM.
PARTICIPANTS: Two thousand three hundred seventy-two patients with SPM and 1206 with MPM.
EXPOSURE: Diagnosis with melanoma.
MAIN OUTCOMES AND MEASURES: Melanoma-specific fatality hazard ratios (HR) and 95% confidence intervals associated with clinical and pathological characteristics of SPM, MPM, and both in Cox proportional hazards regression models.
RESULTS: Melanoma thickness was the main determinant of fatality (HR for >4 mm, 7.68 [95% CI, 4.46-13.23]); other independent predictors were ulceration, mitoses, and scalp location. After adjustment for these other predictors, we found little difference in fatality between MPM and SPM (HR for MPM relative to SPM, 1.24 [95% CI, 0.91-1.69; P = .18]). Thicker SPM, however, had higher fatality (HR for >4 mm, 13.56 [95% CI, 6.47-28.40]) than thicker MPM (2.93 [1.17-7.30]).
CONCLUSIONS AND RELEVANCE: Although overall fatalities due to SPM and MPM were similar, relative fatality for thicker SPM was greater than that for thicker MPM. This finding may offer support for a difference in outcome between patients with SPM and MPM related to factors other than closer surveillance and earlier diagnosis. The better outcomes are worth further exploration.

Fang ZQ, Zang WD, Chen R, et al.
Gene expression profile and enrichment pathways in different stages of bladder cancer.
Genet Mol Res. 2013; 12(2):1479-89 [PubMed] Related Publications
Bladder cancer is a highly heterogeneous neoplasm. We examined the gene expression profile in 3 bladder cancer stages (Ta, T1, T2) using expression microarray analysis of 40 bladder tumors. Differentially expressed genes were found by the t-test, with <0.005 as the significance threshold. KEGG pathway-enrichment analysis was used to study the signaling pathways of the genes. We found 36 genes that could be used as molecular markers for predicting the transition from Ta-T1 to T1-T2. Among these, 11 overlapped between Ta-T1 and T1-T2 stages. Six genes were down-regulated at the Ta-T1 stage, but were up-regulated at the T1-T2 stage (ANXA5, ATP6V1B2, CTGF, GEM, IL13RA1, and LCP1); 5 genes were up-regulated at the Ta-T1 stage, but down-regulated at the T1-T2 stage (ACPP, GNL1, RIPK1, RAPGEF3, and ZER1). Another 25 genes changed relative expression levels at the T1-T2 stage. These genes (including COL1A1, COL1A2, FN1, ITGA5, LGALS1, SPP1, VIM, POSTN, and COL18A1) may be involved in bladder cancer progression by affecting extracellular matrix-receptor interaction and focal adhesion. The cytokine-cytokine receptor interaction, neuroactive ligand-receptor interaction, and calcium-signaling pathway were associated with bladder cancer progression at both the Ta-T1 and T1-T2 stages.

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