TSC1

Gene Summary

Gene:TSC1; TSC complex subunit 1
Aliases: LAM, TSC
Location:9q34.13
Summary:This gene is a tumor suppressor gene that encodes the growth inhibitory protein hamartin. The encoded protein interacts with and stabilizes the GTPase activating protein tuberin. This hamartin-tuberin complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signalling which is a major regulator of anabolic cell growth. This protein also functions as a co-chaperone for Hsp90 that inhibits its ATPase activity. This protein functions as a facilitator of Hsp90-mediated folding of kinase and non-kinase clients, including Tsc2 and thereby preventing their ubiquitination and proteasomal degradation. Mutations in this gene have been associated with tuberous sclerosis. [provided by RefSeq, Apr 2018]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:hamartin
Source:NCBIAccessed: 31 August, 2019

Ontology:

What does this gene/protein do?
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Pathways:What pathways are this gene/protein implicaed in?
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Cancer Overview

Research Indicators

Publications Per Year (1994-2019)
Graph generated 31 August 2019 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.

Tag cloud generated 31 August, 2019 using data from PubMed, MeSH and CancerIndex

Specific Cancers (5)

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: TSC1 (cancer-related)

Kutahyalioglu M, Nguyen HT, Kwatampora L, et al.
Genetic profiling as a clinical tool in advanced parathyroid carcinoma.
J Cancer Res Clin Oncol. 2019; 145(8):1977-1986 [PubMed] Related Publications
CONTEXT: Parathyroid carcinoma (PC) is a rare endocrine malignancy with no approved systemic therapies for unresectable locally invasive or distant metastatic disease. Understanding the molecular changes in advanced PC can provide better understanding of this disease and potentially help directing targeted therapy.
OBJECTIVE: To evaluate tumor-specific genetic changes using next-generation sequencing (NGS) panels.
DESIGN: All patients with advanced PC were tested for hot-spot panels using NGS panels including a 50-gene panel, a 409-gene panel if the standard 50-gene panel (Ion Torrent, Life Technology) was negative or a FoundationOne panel.
SETTING: The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
PATIENTS OR OTHER PARTICIPANTS: 11 patients with advanced PC were selected to undergo molecular testing.
MAIN OUTCOME MEASURE(S): Genetic profiles of advanced PC.
RESULTS: Among the 11 patients, 4 patients had the 50-gene panel only, 6 had 409-gene panel after a negative 50-gene panel and 1 had FoundationOne. One patient who had 50-gene panel only also had his metastatic site (esophagus) of his tumor tested with FoundationOne. The most common mutations identified were in the PI3 K (PIK3CA, TSC1 and ATM) (4/11 patients) and TP53 (3/11) pathways. Genes not previously reported to be mutated in PC included: SDHA, TERT promoter and DICER1. Actionable mutations were found in 54% (6/11) of the patients.
CONCLUSIONS: Mutational profiling using NGS panels in advanced PC has yielded important potentially targetable genetic alterations. Larger studies are needed to identify commonly mutated genes in advanced PC patients. Development of novel therapies targeting these cellular pathways should be considered.

Bell CC, Fennell KA, Chan YC, et al.
Targeting enhancer switching overcomes non-genetic drug resistance in acute myeloid leukaemia.
Nat Commun. 2019; 10(1):2723 [PubMed] Free Access to Full Article Related Publications
Non-genetic drug resistance is increasingly recognised in various cancers. Molecular insights into this process are lacking and it is unknown whether stable non-genetic resistance can be overcome. Using single cell RNA-sequencing of paired drug naïve and resistant AML patient samples and cellular barcoding in a unique mouse model of non-genetic resistance, here we demonstrate that transcriptional plasticity drives stable epigenetic resistance. With a CRISPR-Cas9 screen we identify regulators of enhancer function as important modulators of the resistant cell state. We show that inhibition of Lsd1 (Kdm1a) is able to overcome stable epigenetic resistance by facilitating the binding of the pioneer factor, Pu.1 and cofactor, Irf8, to nucleate new enhancers that regulate the expression of key survival genes. This enhancer switching results in the re-distribution of transcriptional co-activators, including Brd4, and provides the opportunity to disable their activity and overcome epigenetic resistance. Together these findings highlight key principles to help counteract non-genetic drug resistance.

Bandopadhayay P, Piccioni F, O'Rourke R, et al.
Neuronal differentiation and cell-cycle programs mediate response to BET-bromodomain inhibition in MYC-driven medulloblastoma.
Nat Commun. 2019; 10(1):2400 [PubMed] Free Access to Full Article Related Publications
BET-bromodomain inhibition (BETi) has shown pre-clinical promise for MYC-amplified medulloblastoma. However, the mechanisms for its action, and ultimately for resistance, have not been fully defined. Here, using a combination of expression profiling, genome-scale CRISPR/Cas9-mediated loss of function and ORF/cDNA driven rescue screens, and cell-based models of spontaneous resistance, we identify bHLH/homeobox transcription factors and cell-cycle regulators as key genes mediating BETi's response and resistance. Cells that acquire drug tolerance exhibit a more neuronally differentiated cell-state and expression of lineage-specific bHLH/homeobox transcription factors. However, they do not terminally differentiate, maintain expression of CCND2, and continue to cycle through S-phase. Moreover, CDK4/CDK6 inhibition delays acquisition of resistance. Therefore, our data provide insights about the mechanisms underlying BETi effects and the appearance of resistance and support the therapeutic use of combined cell-cycle inhibitors with BETi in MYC-amplified medulloblastoma.

Liu X, Zhang Y, Hao Y, et al.
Tuberous sclerosis complex presenting as convulsive status epilepticus followed by hypoxic cerebropathy: A case report.
Medicine (Baltimore). 2019; 98(19):e15545 [PubMed] Free Access to Full Article Related Publications
RATIONALE: Tuberous sclerosis complex (TSC) is a relatively rare, autosomal dominant, and progressive neurocutaneous disorder involving multiple organs. Heterozygous mutations in the TSC1 gene located on chromosome 9 (9q34.13) or the TSC2 gene located on chromosome 16 (16p13.3) have been shown to be responsible for this disorder. The most common clinical manifestations are abnormalities of the skin, brain, kidney, heart, and lungs. Although all seizure types have been observed in TSC patients, the present case is the first in the literature to present with convulsive status epilepticus followed by hypoxic cerebropathy.
PATIENT CONCERNS: A 33-month-old girl presented with fever and seizure followed by unconsciousness for 6 hours. Physical examination showed 4 hypopigmented macules with diameters exceeding 5 mm. Initial magnetic resonance imaging of the brain revealed diffuse edema in the bilateral cerebral cortex, cortical tubers, and subependymal nodules. Video electroencephalography showed no epileptiform activity, but diffuse slow waves intermixed with small fast waves were seen for all leads. Computed tomography brain scanning revealed bilateral cortex edema and calcified subependymal nodules.
DIAGNOSIS: Combined with her clinical presentation, the patient was diagnosed with TSC after molecular analysis revealed she had inherited the TSC2 c.1832G>A (p.R611Q) mutation from her mother.
INTERVENTIONS: The patient received anti-infection therapy, mannitol dehydration, hyperbaric oxygen treatment, and topiramate.
OUTCOMES: One month later, the patient was in a decorticate state, presenting with unconsciousness and bilateral arm flexion and leg extension. At 6 weeks, repeated electroencephalography was normal.
LESSONS: In addition to the present case report, rare studies have reported cases of TSC presenting as convulsive status epileticus followed by hypoxic cerebropathy, which may be strongly associated with a poor prognosis. Patients with the characteristic skin lesions and epilepsy should be carefully evaluated for the possible diagnosis of TSC.

Xia Y, Lam CS, Li W, et al.
Flexicaulin A, An
Int J Mol Sci. 2019; 20(8) [PubMed] Free Access to Full Article Related Publications
Natural products, explicitly medicinal plants, are an important source of inspiration of antitumor drugs, because they contain astounding amounts of small molecules that possess diversifying chemical entities. For instance,

Kim TW, Han SR, Kim JT, et al.
Differential expression of tescalcin by modification of promoter methylation controls cell survival in gastric cancer cells.
Oncol Rep. 2019; 41(6):3464-3474 [PubMed] Related Publications
The EF‑hand calcium binding protein tescalcin (TESC) is highly expressed in various human and mouse cancer tissues and is therefore considered a potential oncogene. However, the underlying mechanism that governs TESC expression remains unclear. Emerging evidence suggests that TESC expression is under epigenetic regulation. In the present study, the relationship between the epigenetic modification and gene expression of TESC in gastric cancer was investigated. To evaluate the relationship between the methylation and expression of TESC in gastric cancer, the methylation status of CpG sites in the TESC promoter was analyzed using microarray with the Illumina Human Methylation27 BeadChip (HumanMethylation27_270596_v.1.2), gene profiles from the NCBI Dataset that revealed demethylated status were acquired, and real‑time methylation‑specific PCR (MSP) in gastric cancer cells was conducted. In the present study, it was demonstrated that the hypermethylation of TESC led to the downregulation of TESC mRNA/protein expression. In addition, 5‑aza‑2c‑deoxycytidine (5'‑aza‑dC) restored TESC expression in the tested gastric cancer cells except for SNU‑620 cells. ChIP assay further revealed that the methylation of the TESC promoter was associated with methyl‑CpG binding domain protein (MBD)1, histone deacetylase (HDAC)2, and Oct‑1 and that treatment with 5'‑aza‑dC facilitated the dissociation of MBD1, HDAC2, and Oct‑1 from the promoter of TESC. Moreover, silencing of TESC increased MBD1 expression and decreased the H3K4me2/3 level, thereby causing transcriptional repression and suppression of cell survival in NCI‑N87 cells; conversely, overexpression of TESC downregulated MBD1 expression and upregulated the H3K4me2 level associated with active transcription in SNU‑638 cells. These results indicated that the differential expression of TESC via the modification status of the promoter and histone methylation controled cell survival in gastric cancer cells. Overall, the present study provided a novel therapeutic strategy for gastric cancer.

Gao R, Sun TT
Effects of CD133 on the biological features and
J Biol Regul Homeost Agents. 2019 Mar-Apr,; 33(2):355-364 [PubMed] Related Publications
This study aimed to investigate the effect of CD133 on the proliferation and migration of glioma cells and expressions of genes related to cancer stem cells/tumor stem cells (CSC/TSC) as well as their in-vivo oncogenicity. CD133-overexpressing U251-CD133 and U251-mock glioma cells were constructed. The effect of CD133 on in-vitro proliferation and the neurosphere-forming ability of glioma cells was determined by cell count and neurosphere formation assay. Real-Time PCR was performed to detect the expressions of CSC/TSC-related genes in the CD133-transfected cells. Nude mouse subcutaneous tumor formation assay was used to determine the effect of CD133 on the in-vivo oncogenicity of glioma cells. In serum-containing medium, human CD133 had no impact on the proliferation of U251 glioma cells, but the neural stem cells placed in serum-free medium promoted neurosphere formation. In the presence of CD133, the expressions of CSC/TSC-related genes were upregulated to varying degrees in glioma cells; CD133 greatly enhanced the in-vivo oncogenicity. In conclusion, CD133 promoted the upregulation of CSC/TSC-related genes in glioma cells, while enhancing the neurosphere-forming ability and in-vivo oncogenicity.

Zhang Q, Yu S, Lam MMT, et al.
Angiotensin II promotes ovarian cancer spheroid formation and metastasis by upregulation of lipid desaturation and suppression of endoplasmic reticulum stress.
J Exp Clin Cancer Res. 2019; 38(1):116 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Angiotensin II (ANGII) and its receptor (AGTR1) have been proposed as significant contributors to metastasis in multiple cancers. Further, high AGTR1 levels are associated with poor epithelial ovarian cancer (EOC) outcomes. However, the mechanistic basis for these effects is unknown. Recent studies have suggested that ovarian cancer metastasis is highly dependent on the formation of multicellular spheroids (MCS). To understand the associations between the ANGII/AGTR1 pathway and cancer outcomes, we evaluated the effects of ANGII on MCS formation by ovarian cancer cells and used a proteomic approach to analyze the mechanistic basis.
METHODS: We used the data from the GENT database and immunohistochemistry staining to assess the AGTR1 expression in epithelial ovarian cancer (EOC) patients and to assess its role in cancer progression. Colony formation assay, 3D culture assay, and transwell assays were used to analyze the effect of ANGII on the MCS formation and cell migration. The signaling pathways of AGTR1 and transactivation of epidermal growth factor receptor (EGFR) transactivation were investigated by the western blotting analysis. Xenograft models were used to determine the role of AGTR1 in ovarian cancer metastasis. ANGII release from ovarian cancer cells and ANGII levels in the EOC ascites fluid were measured by immunoassay. A shotgun proteomic approach was used to explore the detail molecular mechanism. Modulation of lipid desaturation and endoplasmic reticulum stress were verified by the in vitro and in vivo functional assays.
RESULTS: AGTR1 expression was negatively correlated with EOC prognosis. AGTR1activation significantly enhanced the MCS formation and cell migration. ANGII triggered both of the classical AGTR1 pathway and the EGFR transactivation. ANGII administration increased peritoneal metastasis. In addition, ovarian cancer cells secreted ANGII and enhanced cancer metastasis in a positive feedback manner. Based on the proteomic data, lipid desaturation was activated by induction of stearoyl-CoA desaturase-1 (SCD1), which suggests that inhibition of SCD1 may significantly reduce MCS formation by increasing endoplasmic reticulum stress.
CONCLUSIONS: ANGII promotes MCS formation and peritoneal metastasis of EOC cells. AGTR1 activation increases the lipid desaturation via SCD1 upregulation, which ultimately reduces endoplasmic reticulum stress in MCS. This mechanism explained the association between high levels of AGTR1 and poor clinical outcomes in EOC patients.

Sahraeian SME, Liu R, Lau B, et al.
Deep convolutional neural networks for accurate somatic mutation detection.
Nat Commun. 2019; 10(1):1041 [PubMed] Free Access to Full Article Related Publications
Accurate detection of somatic mutations is still a challenge in cancer analysis. Here we present NeuSomatic, the first convolutional neural network approach for somatic mutation detection, which significantly outperforms previous methods on different sequencing platforms, sequencing strategies, and tumor purities. NeuSomatic summarizes sequence alignments into small matrices and incorporates more than a hundred features to capture mutation signals effectively. It can be used universally as a stand-alone somatic mutation detection method or with an ensemble of existing methods to achieve the highest accuracy.

He X, Yin F, Wang D, et al.
AIE Featured Inorganic-Organic Core@Shell Nanoparticles for High-Efficiency siRNA Delivery and Real-Time Monitoring.
Nano Lett. 2019; 19(4):2272-2279 [PubMed] Related Publications
RNA interference (RNAi) is demonstrated as one of the most powerful technologies for sequence-specific suppression of genes in disease therapeutics. Exploration of novel vehicles for small interfering RNA (siRNA) delivery with high efficiency, low cytotoxicity, and self-monitoring functionality is persistently pursued. Herein, by taking advantage of aggregation-induced emission luminogen (AIEgen), we developed a novel class of Ag@AIE core@shell nanocarriers with regulable and uniform morphology. It presented excellent efficiencies in siRNA delivery, target gene knockdown, and cancer cell inhibition in vitro. What's more, an anticancer efficacy up to 75% was achieved in small animal experiments without obvious toxicity. Attributing to the unique AIE properties, real-time intracellular tracking of siRNA delivery and long-term tumor tissue imaging were successfully realized. Compared to the commercial transfection reagents, significant improvements were obtained in biocompatibility, delivery efficiency, and reproducibility, representing a promising future of this nanocarrier in RNAi-related cancer therapeutics.

Mamoori A, Wahab R, Vider J, et al.
The tumour suppressor effects and regulation of cancer stem cells by macrophage migration inhibitory factor targeted miR-451 in colon cancer.
Gene. 2019; 697:165-174 [PubMed] Related Publications
BACKGROUND: This study aimed to investigate the impact of miR-451 on the biological behaviours of colon cancer cells along with its targets interactions.
METHOD: The levels of miR-451 were tested in colon cancer cell lines (SW480 and SW48). Multiple functional and immunological assays were performed to analyse miR-451 induced growth changes in-vitro and downstream effects on target proteins.
RESULTS: Overexpression of miR-451 in colon cancer cells led to reduced cell proliferation, increased apoptosis and decrease accumulation of the cells at the G0/G1 phase of the cell cycle. In addition, a significant increase in the number of the cells was noted in the G2-M phase of cell cycle. Moreover, miR-451 reduced the expression of Oct-4, Sox-2 and Snail indicating its role in stem cell and epithelial-mesenchymal transition (EMT) regulation. An inverse correlation between miR-451 and macrophage migration inhibitory protein (MIF) protein expression occurred in colon cancer cells. Furthermore, restoration the level of miR-451 in colon cancer cells inhibits tumour spheres formation.
CONCLUSION: miR-451 has tumour suppressor effects in vitro, which can inhibit the cancer-related signalling pathways in colon cancer.

He B, Gao R, Lv D, et al.
The prognostic landscape of interactive biological processes presents treatment responses in cancer.
EBioMedicine. 2019; 41:120-133 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Differential gene expression patterns are commonly used as biomarkers to predict treatment responses among heterogeneous tumors. However, the link between response biomarkers and treatment-targeting biological processes remain poorly understood. Here, we develop a prognosis-guided approach to establish the determinants of treatment response.
METHODS: The prognoses of biological processes were evaluated by integrating the transcriptomes and clinical outcomes of ~26,000 cases across 39 malignancies. Gene-prognosis scores of 39 malignancies (GEO datasets) were used for examining the prognoses, and TCGA datasets were selected for validation. The Oncomine and GEO datasets were used to establish and validate transcriptional signatures for treatment responses.
FINDINGS: The prognostic landscape of biological processes was established across 39 malignancies. Notably, the prognoses of biological processes varied among cancer types, and transcriptional features underlying these prognostic patterns distinguished response to treatment targeting specific biological process. Applying this metric, we found that low tumor proliferation rates predicted favorable prognosis, whereas elevated cellular stress response signatures signified resistance to anti-proliferation treatment. Moreover, while high immune activities were associated with favorable prognosis, enhanced lipid metabolism signatures distinguished immunotherapy resistant patients.
INTERPRETATION: These findings between prognosis and treatment response provide further insights into patient stratification for precision treatments, providing opportunities for further experimental and clinical validations. FUND: National Natural Science Foundation, Innovative Research Team in University of Ministry of Education of China, National Key Research and Development Program, Natural Science Foundation of Guangdong, Science and Technology Planning Project of Guangzhou, MRC, CRUK, Breast Cancer Now, Imperial ECMC, NIHR Imperial BRC and NIH.

Pal R, Xiong Y, Sardiello M
Abnormal glycogen storage in tuberous sclerosis complex caused by impairment of mTORC1-dependent and -independent signaling pathways.
Proc Natl Acad Sci U S A. 2019; 116(8):2977-2986 [PubMed] Free Access to Full Article Related Publications
Tuberous sclerosis complex (TSC) is an autosomal dominant syndrome that causes tumor formation in multiple organs. TSC is caused by inactivating mutations in the genes encoding TSC1/2, negative regulators of the mammalian target of rapamycin complex 1 (mTORC1). Diminished TSC function is associated with excess glycogen storage, but the causative mechanism is unknown. By studying human and mouse cells with defective or absent TSC2, we show that complete loss of TSC2 causes an increase in glycogen synthesis through mTORC1 hyperactivation and subsequent inactivation of glycogen synthase kinase 3β (GSK3β), a negative regulator of glycogen synthesis. Specific TSC2 pathogenic mutations, however, result in elevated glycogen levels with no changes in mTORC1 or GSK3β activities. We identify mTORC1-independent lysosomal depletion and impairment of autophagy as the driving causes underlying abnormal glycogen storage in TSC irrespective of the underlying mutation. The defective autophagic degradation of glycogen is associated with abnormal ubiquitination and degradation of essential proteins of the autophagy-lysosome pathway, such as LC3 and lysosomal associated membrane protein 1 and 2 (LAMP1/2) and is restored by the combined use of mTORC1 and Akt pharmacological inhibitors. In complementation to current models that place mTORC1 as the central therapeutic target for TSC pathogenesis, our findings identify mTORC1-independent pathways that are dysregulated in TSC and that should therefore be taken into account in the development of a therapeutic treatment.

Jiang X, Finucane HK, Schumacher FR, et al.
Shared heritability and functional enrichment across six solid cancers.
Nat Commun. 2019; 10(1):431 [PubMed] Free Access to Full Article Related Publications
Quantifying the genetic correlation between cancers can provide important insights into the mechanisms driving cancer etiology. Using genome-wide association study summary statistics across six cancer types based on a total of 296,215 cases and 301,319 controls of European ancestry, here we estimate the pair-wise genetic correlations between breast, colorectal, head/neck, lung, ovary and prostate cancer, and between cancers and 38 other diseases. We observed statistically significant genetic correlations between lung and head/neck cancer (r

Ferrari N, Ranftl R, Chicherova I, et al.
Dickkopf-3 links HSF1 and YAP/TAZ signalling to control aggressive behaviours in cancer-associated fibroblasts.
Nat Commun. 2019; 10(1):130 [PubMed] Free Access to Full Article Related Publications
Aggressive behaviours of solid tumours are highly influenced by the tumour microenvironment. Multiple signalling pathways can affect the normal function of stromal fibroblasts in tumours, but how these events are coordinated to generate tumour-promoting cancer-associated fibroblasts (CAFs) is not well understood. Here we show that stromal expression of Dickkopf-3 (DKK3) is associated with aggressive breast, colorectal and ovarian cancers. We demonstrate that DKK3 is a HSF1 effector that modulates the pro-tumorigenic behaviour of CAFs in vitro and in vivo. DKK3 orchestrates a concomitant activation of β-catenin and YAP/TAZ. Whereas β-catenin is dispensable for CAF-mediated ECM remodelling, cancer cell growth and invasion, DKK3-driven YAP/TAZ activation is required to induce tumour-promoting phenotypes. Mechanistically, DKK3 in CAFs acts via canonical Wnt signalling by interfering with the negative regulator Kremen and increasing cell-surface levels of LRP6. This work reveals an unpredicted link between HSF1, Wnt signalling and YAP/TAZ relevant for the generation of tumour-promoting CAFs.

Parzych K, Saavedra-García P, Valbuena GN, et al.
The coordinated action of VCP/p97 and GCN2 regulates cancer cell metabolism and proteostasis during nutrient limitation.
Oncogene. 2019; 38(17):3216-3231 [PubMed] Related Publications
VCP/p97 regulates numerous cellular functions by mediating protein degradation through its segregase activity. Its key role in governing protein homoeostasis has made VCP/p97 an appealing anticancer drug target. Here, we provide evidence that VCP/p97 acts as a regulator of cellular metabolism. We found that VCP/p97 was tied to multiple metabolic processes on the gene expression level in a diverse range of cancer cell lines and in patient-derived multiple myeloma cells. Cellular VCP/p97 dependency to maintain proteostasis was increased under conditions of glucose and glutamine limitation in a range of cancer cell lines from different tissues. Moreover, glutamine depletion led to increased VCP/p97 expression, whereas VCP/p97 inhibition perturbed metabolic processes and intracellular amino acid turnover. GCN2, an amino acid-sensing kinase, attenuated stress signalling and cell death triggered by VCP/p97 inhibition and nutrient shortages and modulated ERK activation, autophagy, and glycolytic metabolite turnover. Together, our data point to an interconnected role of VCP/p97 and GCN2 in maintaining cancer cell metabolic and protein homoeostasis.

Zhang S, Zhang H, Ghia EM, et al.
Inhibition of chemotherapy resistant breast cancer stem cells by a ROR1 specific antibody.
Proc Natl Acad Sci U S A. 2019; 116(4):1370-1377 [PubMed] Free Access to Full Article Related Publications
Breast cancers enduring treatment with chemotherapy may be enriched for cancer stem cells or tumor-initiating cells, which have an enhanced capacity for self-renewal, tumor initiation, and/or metastasis. Breast cancer cells that express the type I tyrosine kinaselike orphan receptor ROR1 also may have such features. Here we find that the expression of ROR1 increased in breast cancer cells following treatment with chemotherapy, which also enhanced expression of genes induced by the activation of Rho-GTPases, Hippo-YAP/TAZ, or B lymphoma Mo-MLV insertion region 1 homolog (BMI1). Expression of ROR1 also enhanced the capacity of breast cancer cells to invade Matrigel, form spheroids, engraft in Rag2

Luo AJ, Tan J, He LY, et al.
Suppression of Tescalcin inhibits growth and metastasis in renal cell carcinoma via downregulating NHE1 and NF-kB signaling.
Exp Mol Pathol. 2019; 107:110-117 [PubMed] Related Publications
BACKGROUND: Renal cell carcinoma (RCC) is the most common form of kidney cancer. Recent studies reported that Tescalcin was overexpressed in various tumor types. However, the status of Tescalcin protein expression in RCC and its biological function is uncertain. This study was designed to investigate the expression of Tescalcin in human RCC and its biological function.
METHODS: shRNA transfection was performed to abrogates the expression of Tescalcin. Quantitative real time PCR and western blotting assays were used to determine mRNA and protein expression levels, respectively. The cell viability was analyzed by MTT and colony formation. Cell flow cytometry was used to assess pHi value and cell apoptosis. Cell invasive and migratory ability was measured with modified Boyden chamber assay. Xenograft model was setup to evaluate tumor growth.
RESULTS: Tescalcin was overexpressed in RCC tissues compared with matched normal tissues. It was also overexpressed in RCC cell lines relative that of normal cells. Suppression Tescalcin with specific shRNA resulted in the inhibition of cell proliferation, migration, invasion and apoptosis of RCC cells. Additionally, silencing of Tescalcin also caused the inhibition of the tumor growth in nude mice. Mechanistic study showed that Tescalcin regulated cell proliferation, migration and invasion via NHE1/pHi axis as well as AKT/NF-κB signaling pathway.
CONCLUSIONS: These findings demonstrate that atopic expression of Tescalcin facilitates the survival, migration and invasion of RCC cells via NHE1/pHi axis as well as AKT/ NF-κB signaling pathway, providing new perspectives for the future study of Tescalcin as a therapeutic target for RCC.

Ahsanul Kabir KM, Amin R, Hasan I, et al.
Geodorum densiflorum rhizome lectin inhibits Ehrlich ascites carcinoma cell growth by inducing apoptosis through the regulation of BAX, p53 and NF-κB genes expression.
Int J Biol Macromol. 2019; 125:92-98 [PubMed] Related Publications
A lectin with a molecular mass of 12 ± 1 kDa was isolated for the first time from Geodorum densiflorum (Lam.) rhizome (GDL). The lectin exhibited hemagglutination activity both in mice and human erythrocytes which was inhibited by 4-nitrophenyl-β-D-glucopyranoside among the tested 26 sugars. The lectin was heat stable and showed its full activity in the pH range from 5.0 to 9.0. The lectin did not lose its activity in the presence of urea but the activity lost significantly when treated with EDTA. Divalent cation Ca

Vervoort SJ, de Jong OG, Roukens MG, et al.
Global transcriptional analysis identifies a novel role for SOX4 in tumor-induced angiogenesis.
Elife. 2018; 7 [PubMed] Free Access to Full Article Related Publications
The expression of the transcription factor

Kuzniewska B, Sadowski K, Urbanska K, et al.
The level of microRNA 21 is upregulated by rapamycin in serum of tuberous sclerosis complex patients and subependymal giant cell astrocytoma (SEGA)-derived cell cultures.
Folia Neuropathol. 2018; 56(3):167-174 [PubMed] Related Publications
Tuberous sclerosis complex (TSC) represents a genetic condition, in which the clinical manifestations are caused by the disinhibition of the mammalian target of rapamycin (mTOR) pathway due to mutations in the TSC1 (hamartin) or TSC2 (tuberin) genes. The deregulated mTOR activity leads to multi-site tumors, including subependymal giant cell astrocytoma (SEGA). SEGA is a brain tumor that affects around 15% of TSC patients. The aim of the study was to evaluate miR-21 expression in the serum of two groups of TSC patients: with or without SEGA tumors. We found no differences in the level of miR-21 depending on the presence of SEGA. Next, we studied the influence of prolonged rapamycin administration on miR-21 level in the blood serum of TSC patients (6-12 months of rapamycin) and in primary cultures of SEGA-derived cells treated with rapamycin in vitro. Here we show that rapamycin treatment leads to the upregulation of miR-21 in both patients' serum and in primary SEGA tumor cells in the culture indicating the regulatory relationship between rapamycin treatment and miR-21 expression.

Poulos RC, Wong YT, Ryan R, et al.
Analysis of 7,815 cancer exomes reveals associations between mutational processes and somatic driver mutations.
PLoS Genet. 2018; 14(11):e1007779 [PubMed] Free Access to Full Article Related Publications
Driver mutations are the genetic variants responsible for oncogenesis, but how specific somatic mutational events arise in cells remains poorly understood. Mutational signatures derive from the frequency of mutated trinucleotides in a given cancer sample, and they provide an avenue for investigating the underlying mutational processes that operate in cancer. Here we analyse somatic mutations from 7,815 cancer exomes from The Cancer Genome Atlas (TCGA) across 26 cancer types. We curate a list of 50 known cancer driver mutations by analysing recurrence in our cohort and annotations of known cancer-associated genes from the Cancer Gene Census, IntOGen database and Cancer Genome Interpreter. We then use these datasets to perform binary univariate logistic regression and establish the statistical relationship between individual driver mutations and known mutational signatures across different cancer types. Our analysis led to the identification of 39 significant associations between driver mutations and mutational signatures (P < 0.004, with a false discovery rate of < 5%). We first validate our methodology by establishing statistical links for known and novel associations between driver mutations and the mutational signature arising from Polymerase Epsilon proofreading deficiency. We then examine associations between driver mutations and mutational signatures for AID/APOBEC enzyme activity and deficient mismatch repair. We also identify negative associations (odds ratio < 1) between mutational signatures and driver mutations, and here we examine the role of aging and cigarette smoke mutagenesis in the generation of driver mutations in IDH1 and KRAS in brain cancers and lung adenocarcinomas respectively. Our study provides statistical foundations for hypothesised links between otherwise independent biological processes and we uncover previously unexplored relationships between driver mutations and mutagenic processes during cancer development. These associations give insights into how cancers acquire advantageous mutations and can provide direction to guide further mechanistic studies into cancer pathogenesis.

Wang N, Liang X, Yu W, et al.
Differential Expression of MicroRNA-19b Promotes Proliferation of Cancer Stem Cells by Regulating the TSC1/mTOR Signaling Pathway in Multiple Myeloma.
Cell Physiol Biochem. 2018; 50(5):1804-1814 [PubMed] Related Publications
BACKGROUND/AIMS: MiR-19b has been reported to be involved in several malignancies, but its role in multiple myeloma (MM) is still unknown. The objective of this study was to explore the biological mechanism of miR-19b in the progression of MM.
METHODS: First, we performed real-time polymerase chain reaction (PCR) and Western blot to study the expression of miR-19b, tuberous sclerosis 1 (TSC1), and caspase-3 in different groups. MTT assay was performed to explore the effect of miR-19b on survival and apoptosis of cancer stem cells (CSCs). Computation analysis and luciferase assay were utilized to confirm the interaction between miR-19b and TSC1.
RESULTS: A total of 38 participants comprising 20 subjects with MM and 18 healthy subjects as normal controls were enrolled in our study. Real-time PCR showed dramatic upregulation of miR-19b, but TSC1 was evidently suppressed in the MM group. MiR-19b overexpression substantially promoted clonogenicity and cell viability, and further inhibited apoptosis of CSCs in vitro. Furthermore, miR-19b overexpression downregulated the expression of caspase-3, which induced apoptosis. Using in silico analysis, we identified that TSC1 might be a direct downstream target of miR-19b, and this was further confirmed by luciferase assay showing that miR-19b apparently reduced the luciferase activity of wild-type TSC1 3´-UTR, but not that of mutant TSC1 3´-UTR. There was also evident decrease in TSC1 mRNA and protein in CSCs following introduction of miR-19b. Interestingly, reintroduction of TSC1 abolished the miR-19b-induced proliferation promotion and apoptosis inhibition in CSCs.
CONCLUSION: These findings collectively suggest that miR-19b promotes cell survival and suppresses apoptosis of MM CSCs via targeting TSC1 directly, indicating that miR-19b may serve as a potential and novel therapeutic target of MM based on miRNA expression.

Harding JJ, Nandakumar S, Armenia J, et al.
Prospective Genotyping of Hepatocellular Carcinoma: Clinical Implications of Next-Generation Sequencing for Matching Patients to Targeted and Immune Therapies.
Clin Cancer Res. 2019; 25(7):2116-2126 [PubMed] Article available free on PMC after 01/04/2020 Related Publications
PURPOSE: Prior molecular profiling of hepatocellular carcinoma (HCC) has identified actionable findings that may have a role in guiding therapeutic decision-making and clinical trial enrollment. We implemented prospective next-generation sequencing (NGS) in the clinic to determine whether such analyses provide predictive and/or prognostic information for HCC patients treated with contemporary systemic therapies.
EXPERIMENTAL DESIGN: Matched tumor/normal DNA from patients with HCC (
RESULTS: WNT/β-catenin pathway (45%) and
CONCLUSIONS: Linking NGS to routine clinical care has the potential to identify those patients with HCC likely to benefit from standard systemic therapies and can be used in an investigational context to match patients to genome-directed targeted therapies.

Huebbers CU, Verhees F, Poluschkin L, et al.
Upregulation of AKR1C1 and AKR1C3 expression in OPSCC with integrated HPV16 and HPV-negative tumors is an indicator of poor prognosis.
Int J Cancer. 2019; 144(10):2465-2477 [PubMed] Related Publications
Different studies have shown that HPV16-positive OPSCC can be subdivided based on integration status (integrated, episomal and mixed forms). Because we showed that integration neither affects the levels of viral genes, nor those of virally disrupted human genes, a genome-wide screen was performed to identify human genes which expression is influenced by viral integration and have clinical relevance. Thirty-three fresh-frozen HPV-16 positive OPSCC samples with known integration status were analyzed by mRNA expression profiling. Among the genes of interest, Aldo-keto-reductases 1C1 and 1C3 (AKR1C1, AKR1C3) were upregulated in tumors with viral integration. Additionally, 141 OPSCC, including 48 HPV-positive cases, were used to validate protein expression by immunohistochemistry. Results were correlated with clinical and histopathological data. Non-hierarchical clustering resulted in two main groups differing in mRNA expression patterns, which interestingly corresponded with viral integration status. In OPSCC with integrated viral DNA, often metabolic pathways were deregulated with frequent upregulation of AKR1C1 and AKR1C3 transcripts. Survival analysis of 141 additionally immunostained OPSCC showed unfavorable survival rates for tumors with upregulation of AKR1C1 or AKR1C3 (both p <0.0001), both in HPV-positive (p ≤0.001) and -negative (p ≤0.017) tumors. OPSCC with integrated HPV16 show upregulation of AKR1C1 and AKR1C3 expression, which strongly correlates with poor survival rates. Also in HPV-negative tumors, upregulation of these proteins correlates with unfavorable outcome. Deregulated AKR1C expression has also been observed in other tumors, making these genes promising candidates to indicate prognosis. In addition, the availability of inhibitors of these gene products may be utilized for drug treatment.

Cui M, Hu Y, Bi Y, et al.
Preliminary exploration of potential molecular therapeutic targets in recurrent and metastatic parathyroid carcinomas.
Int J Cancer. 2019; 144(3):525-532 [PubMed] Related Publications
Parathyroid carcinoma (PC) is a rare endocrine malignancy. Surgical resection is curative for local lesions, while effective therapies are lacking for recurrent or metastatic PCs. To study whether targeted therapies could be applied in recurrent or metastatic PCs, potential therapeutic targets were identified with next-generation sequencing (NGS). DNA was extracted from formalin-fixed, paraffin-embedded (FFPE) sections from 19 recurrent or metastatic PC samples. A panel of 560 genes was sequenced with NGS to identify genomic alterations at an average sequencing depth of 581×. In total, 190 genomic alterations were identified. Nine PC samples (47%) harbored at least one potentially actionable genomic alteration including in the after genes: ROS1 (5/19; 26%), PTEN (3/19; 16%), TSC1 (2/19; 11%), PIK3CA (1/19; 5%), AKT1 (1/19; 5%), MTOR (1/19; 5%), ERBB2 (1/19; 5%), NTRK1 (1/19; 5%), IDH1 (1/19; 5%) and FGFR3 (1/19; 5%). CDC73 mutations were detected in 9/19 (47%) PC samples. Additional recurrent genomic alterations were identified in MSH2 (15/19; 79%), AR (9/19; 47%), BCR (8/19; 42%), SLC45A3 (6/19; 32%), MAGI1 (5/19; 26%), ZNF521 (4/19; 21%), KMT2C (4/19; 21%) and NOTCH4 (4/19; 21%). Our study identified a relatively high frequency of potentially actionable genomic alterations in PC patients in a Chinese population for the first time. A series of recurrent mutant genes was detected as well. Our study contributes to both the selection of novel targeted therapies for PC and further molecular understanding of this refractory malignancy.

Verma A, Lam YM, Leung YC, et al.
Combined use of arginase and dichloroacetate exhibits anti-proliferative effects in triple negative breast cancer cells.
J Pharm Pharmacol. 2019; 71(3):306-315 [PubMed] Related Publications
OBJECTIVES: Drug combination in cancer therapy aims to achieve synergistic therapeutic effect, reduced drug dosage, reduced drug toxicity and minimizes or delays the induction of drug resistance. In the present study, we investigated the anticancer effects of the combination of two metabolic modulators, dichloroacetate (DCA) and bacillus caldovelox arginase (BCA) (or pegyated human arginase (HA)).
METHODS: The combination treatments were evaluated in MCF-7 and MDA-MB 231 cells as well as in MDA-MB 231 breast cancer xenograft model.
KEY FINDINGS: Dichloroacetate and BCA combination exhibited anti-proliferative effects on MCF-7 cells, which were found to be synergistic. Analysis of the gene expression upon drug treatments revealed that the synergistic anti-proliferative effect on MCF-7 cells was possibly in part due to the activation of the p53 pathway. A similar synergistic anti-proliferative effect was observed in the combined use of DCA and HA on MCF-7 and MDA-MB231 cells, which was due to induction of cell cycle arrest at G2/M phase. Moreover, the combination enhanced anti-tumour activity in a MDA-MB 231 xenograft mouse model.
CONCLUSIONS: Our results suggested that dichloroacetate and arginase combination exhibited enhanced anti-cancer effects in preclinical breast cancer models which may offer an additional treatment option for breast cancer.

Kondo T, Niida Y, Mizuguchi M, et al.
Autopsy case of right ventricular rhabdomyoma in tuberous sclerosis complex.
Leg Med (Tokyo). 2019; 36:37-40 [PubMed] Related Publications
Tuberous sclerosis complex (TSC) is a genetic multisystem disorder characterized by widespread hamartomas in several organs, including the brain, heart, skin, eyes, kidney, lung, and liver. Rhabdomyoma is the most common cardiac tumor diagnosed in fetuses, neonates and infants, and is closely linked to TSC. Here we describe an autopsy case of right ventricular rhabdomyoma in TSC. The deceased was a 3-month-old male infant, and TSC with a cardiac tumor had been diagnosed before his death. Since the cardiac tumor had not been physically blocking the blood flow, he had not undergone surgical intervention. At autopsy, the patient's height was 62 cm and his body weight was 6 kg. The heart weighed 37.3 g and the right ventricle was filled with the tumor. The tumor measured 2.1 cm × 1.6 cm, being a fusion of multiple tumors with several attachment sites to the myocardium. Histologically, the tumor was diagnosed as a rhabdomyoma, and was positive for mammalian target of rapamycin (mTOR). The brain weighed 795.0 g, without hydrocephalus. The cut surface of the brain revealed multiple cortical tubers and subependymal nodules. Through screening for the TSC1 (hamartin) and TSC2 (tuberin) genes, a nonsense mutation, c.1108C>T:p.Gln370

Mencarelli A, Prontera P, Mencarelli A, et al.
Expanding the Clinical Spectrum of Sotos Syndrome in a Patient with the New "c.[5867T>A]+[=]"; "p.[Leu1956Gln]+[=]"
Int J Mol Sci. 2018; 19(10) [PubMed] Article available free on PMC after 01/04/2020 Related Publications
Sotos syndrome is one of the most common overgrowth diseases and it predisposes patients to cancer, generally in childhood. The prevalence of this genetic disorder is 1:10,000⁻1:50,000, and it is characterized by wide allelic heterogeneity, with more than 100 different known mutations in the nuclear receptor-binding SET domain containing protein 1 (

He R, Yin Y, Yin W, et al.
Prevention of pancreatic acinar cell carcinoma by Roux-en-Y Gastric Bypass Surgery.
Nat Commun. 2018; 9(1):4183 [PubMed] Article available free on PMC after 01/04/2020 Related Publications
Roux-en-Y Gastric Bypass Surgery (RYGB) prevents the occurrence of pancreatic cell acinar carcinoma (ACC) in male and female Ngn3-Tsc1-/- mice. Ngn3 directed Cre deletion of Tsc1 gene induced the development of pancreatic ACC. The transgenic mice with sham surgery demonstrated a cancer incidence of 96.7 ± 3.35% and survival rate of 67.0 ± 1.4% at the age of 300 days. Metastasis to liver and kidney was observed in 69.7 ± 9.7% and 44.3 ± 8.01% of these animals, respectively. All animals with RYGB performed at the age of 16 weeks survived free of pancreatic ACC up to the age of 300 days. RYGB significantly attenuated the activation of mTORC1 signaling and inhibition of tumor suppressor genes: p21, p27, and p53 in pancreatic ACC. Our studies demonstrate that bariatric surgery may limit the occurrence and growth of pancreatic ACC through the suppression of mTORC1 signaling in pancreas. RYGB shows promise for intervention of both metabolic dysfunction and organ cancer.

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