Metastasising breast cancer cells communicate with adjacent lymph endothelia, intravasate and disseminate through lymphatic routes, colonise lymph nodes and finally metastasize to distant organs. Thus, understanding and blocking intravasation may attenuate the metastatic cascade at an early step. As a trigger factor, which causes the retraction of lymph endothelial cells (LECs) and opens entry ports for tumour cell intravasation, MDA-MB231 breast cancer cells secrete the pro-metastatic arachidonic acid metabolite, 12S-hydroxy-5Z,8Z,10E,14Z-eicosatetraenoic acid [12(S)-HETE]. In the current study, treatment of LECs with 12(S)-HETE upregulated the expression of the transcription factors SRY-related HMG-box 18 (SOX18) and prospero homeobox protein 1 (PROX1), which determine endothelial development. Thus, whether they have a role in LEC retraction was determined using a validated intravasation assay, small interfering RNA mediated knockdown of gene expression, and mRNA and protein expression analyses. Specific inhibition of SOX18 or PROX1 significantly attenuated in vitro intravasation of MDA-MB231 spheroids through the LEC barrier and 12(S)-HETE-triggered signals were transduced by the high and low affinity receptors, 12(S)-HETE receptor and leukotriene B4 receptor 2. In addition, the current findings indicate that there is crosstalk between SOX18 and nuclear factor κ-light-chain-enhancer of activated B cells, which was demonstrated to contribute to MDA-MB231/lymph endothelial intravasation. The present data demonstrate that the endothelial-specific and lymph endothelial-specific transcription factors SOX18 and PROX1 contribute to LEC retraction.

Aberrant expression of different SOX (SRY-related high mobility group (HMG) box) genes has been observed in number of tumors but, little is known about their expression patterns in hematological malignancies, especially in acute myeloid leukemia (AML). In this study we investigated SOX2, SOX3, SOX11, SOX14 and SOX18 gene expression in 50 de novo adult AML patients and correlated our findings with known clinical and molecular prognostic markers of the disease. We have found that these genes are overexpressed in 10-22% of patients and preliminary findings suggest that high expression level of these genes may have prognostic significance in AML patients. This is the first study focused on examining the expression level of SOX2, SOX3, SOX11, SOX14 and SOX18 genes in AML patients. Although this is a relatively limited study, initial findings indicate the need for further investigation of these genes, their potential roles in leukemia pathogenesis as well as prognosis in AML patients.

Nestin is an intermediate filament protein and a stem cell marker expressed in several tumours. There is growing evidence of an association between the expression level of nestin and the pathogenesis of triple-negative breast cancer (TNBC). Nestin is also expressed in newly forming tumour vessels and is a valuable marker of ongoing angiogenesis. In this study, we aimed to evaluate the prognostic value of nestin expression in breast tumour cells and to determine whether this expression influences angiogenesis. Immunohistochemical (IHC) analyses were carried out on 124 cases of invasive ductal carcinoma (IDC) of the breast with a panel of murine monoclonal antibodies against nestin, CD31, CD34, SOX-18 and Ki‑67. We evaluated nestin expression in tumour and endothelial cells, Ki‑67 in tumour cells, and CD31, CD34 and SOX-18 in endothelial cells. Our results demonstrated that nestin expression in tumour cells correlated with the area and number of vessels expressing nestin, CD31, CD34 and SOX-18. We also found a positive correlation between nestin-expressing vessels and SOX-18-expressing vessels. Our results are consistent with those of previous studies, in which nestin expression in endothelial cells was shown to be strongly associated with triple-negative subtype, poorly differentiated G3 tumours, a higher proliferation index and a shorter overall survival. Nestin expression was also examined in human breast cancer cell lines (MCF-7, SK-BR-3, MDA‑MB‑231 and BO2 cells) representing a different level of tumour aggressiveness and reflecting histological grade. A higher nestin protein level was observed in more aggressive MDA‑MB‑231 and BO2 cells than in MCF-7 and SK-BR-3 cells.

Osteosaroma (OS) is a primary bone malignancy and is associated with high morbidity. Sex determining region Y-box 18 (SOX18) is identified overexpressed in OS. However, the molecular mechanism underlying the biological function of SOX18 in OS is still unclear. The aim of the current study was to determine the SOX18 expression in patients with OS and its effect on tumor cell malignant phenotypes. Our results showed that SOX18 was overexpressed in OS patients from both E-MEXP-3628 database and independent samples from our hospital and in OS cell lines. SOX18 silencing significantly induced G0-G1 phase cell cycle arrest and apoptosis and inhibited U-2OS cell migration and invasion and cell growth both in vitro and in vivo. However, SOX18 overexpression remarkably promoted 143B cell proliferation, migration and invasion and inhibited cell cycle arrest and apoptosis. The protein expression levels of p53, p21, Bax, Bcl-2, and Caspase-3 were also regulated by SOX18. Moreover, SOX18 was found negative correlated with the expression of HERC1, HER2, HERC3, HERC4, HERC5, and HERC6 in OS patients and in OS cells, with the most significant correlation detected in HERC2 expression, which was following found interacted with SOX18 in OS cells. Taken together, our results suggest that SOX18 is overexpressed in OS and plays an important role in proliferation, apoptosis, migration and invasion of OS cells, and may provide a novel and promising thera-peutic strategy for OS.

The molecular pathogenesis of the development of non-small cell lung carcinomas (NSCLCs) is extremely complex. Understanding the molecular basis of the development of this malignant tumor may enable the use of targeted therapy, which may result in a better treatment outome for these patients. Adenocarcinoma (AC) is the most common NSCLC subtype, equally common among smokers and non-smokers, and its pathogenesis remains unknown. The SOX18 protein is an important protein that plays a role in the development of blood and lymphatic vessels during the process of embryogenesis. Recent studies have also shown that the SOX18 protein may play a significant role in tumors, including lung cancers. In the present study, we analyzed the expression of the SOX18 protein and the mRNA level in postoperative samples of AC and non-malignant lung tissues (NMLTs), and a disparity in both levels was observed. Based on our previous observations that miR-7a and miR-24-3p are able to modulate SOX18 expression in NSCLC, the main aim of this study was to verify the miRNA modulation of the SOX18 transcript with the use of the MirTrap System in established lung cancer cell lines NCI-H1703, NCI-H522 and A549. The SOX18 mRNA expression level was significantly lower in AC than that noted in the NMLTs (P<0.0001). However, the protein levels were higher in AC cases compared to levels noted in the NMLTs (P<0.0001). Additionally, correlations between the RQ values of SOX18 in NMLT and AC cases (r=0.8195, P=0.0001), and between miR-7a and miR24-3p in AC cases (r=0.4344, P=0.0016), were noted. In conclusion, we confirmed that miR-7a and miR-24-3p are more highly expressed in NMLTs than in the AC samples, and that they modulate the SOX18 transcript in NSCLC cells.

A small molecule called Sm4 can disrupt interactions involving a transcription factor called Sox18, while having little impact on other members of the SoxF family.

Sex determining region Y (SRY)-box 18 (SOX18) gene encodes transcription factors that have been recently confirmed to be overexpressed in various human types of cancer and maintain the malignant behavior of cancer cells. However, the role and its potential function in prostate cancer (PCa) has not been demonstrated and the mechanisms of SOX18 involved in tumor progression remain largely unclear. In the present study, the expression of SOX18 was analyzed in 98 PCa and 81 adjacent non-tumor tissues using immunohistochemistry. The data showed that SOX18 was overexpressed in 72 of 98 (73.5%) PCa tissues compared with that in 28 of 81 (34.6%) non-tumor tissues. In addition, the expression of SOX18 was related with the clinical features of patients with PCa. To explore the potential role of SOX18 in PCa cells, Cell Counting Kit-8 (CCK-8), migration, invasion and xenograft assays were performed. Our data showed that knockdown of SOX18 decreased the proliferation, migration and invasion of PCa cells in vitro, in addition to the tumor growth in vivo. Markedly, SOX18 knockdown caused the decreased expression of TCF1, c-Myc, cyclin D1 and MMP-7. In conclusion, SOX18 was overexpressed in PCa and may regulate the malignant capacity of cells via the upregulation of TCF1, c-Myc, cyclin D1 and MMP-7.

Recent statistics show that lung cancer is the second most common malignant tumor in the world (14% of all cancers in the USA), both in terms of morbidity and mortality. The mortality of this type of tumor shows an increasing trend (28% for men and 26% for women). Lung squamous cell carcinoma (LSCC) is the second‑largest histological subtype of non‑small cell lung cancers (NSCLCs) after adenocarcinoma. SRY‑related HMG‑box 18 (SOX18) protein is an important transcription factor involved in the development of the cardiovascular system and the lymphatic ducts. In addition, it was observed that SOX18 functions in wound healing processes and the development of atherosclerosis. Likewise, an increased level of this protein was found in melanomas and malignant pancreatic, stomach and breast tumors. Furthermore, high expression of SOX18 in gastric cancer stromal cells was found to be associated with a poor patient prognosis. In the present study, we analyzed the expression of the SOX18 protein and the mRNA level in postoperative samples of LSCC and non‑malignant lung tissues (NMLTs), and a disparity in both levels was observed. Because of the fact that microRNAs (miRNAs) play important roles in the initiation and progression of lung cancer, the main aim of this study was to identify the miRNAs that interact with the SOX18 transcript in NSCLC cases. SOX18 mRNA expression level was significantly lower in the LSCC tissues than that noted in the NMLTs (p<0.01). However, protein levels were higher in the LSCC cases compared to these levels in the NMLTs (p<0.0001). We showed that miR‑7a and miR‑24‑3p were expressed more highly in the NMLTs than levels in the LSCC samples, and that they could be switched off in lung cancer tissue. Additionally, correlations between RQ‑values of SOX18 in NMLTs and LSCC samples (r=0.43, p=0.019), and between miR‑7a and miR24‑3p in NMLT cases (r=0.4, p=0.057) as well as in the LSCC samples (r=0.51, p=0.012) were noted. In conclusion, miRNAs interact with the mRNA of the SOX18 gene, but the mechanism by which they could be inhibited in cancer cells requires further examination.

Transcription factor SOX18 has been proved to play a significant role in carcinogenesis. However, no investigation was performed about the expression of SOX18 in pancreatic ductal adenocarcinoma (PDAC). In our work, we found that the PDAC tissues had higher level of SOX18 mRNA and protein expression than matched non-tumor pancreatic tissues and high level of SOX18 protein indicated poor prognosis for PDAC patients. After knockdown of SOX18 gene in PANC-1 and SW1990 cell lines, which showed higher expression level of SOX18 among five PDAC cell lines, the abilities of proliferation, migration and invasion were inhibited and the tumor growth was suppressed in vivo. In addition, the flow cytometry results indicated that down-regulation of SOX18 induced G1/S phase arrest. Furthermore, we found that the expression of cyclin D1, c-myc and MMP-7, three tumorigenesis promoters, was inhabited with downregulation of SOX18. In conclusion, our study reveals that SOX18 plays a significant role in promoting the growth of PDAC, and might serve as a promising target for PDAC therapy.

SOX7 as a tumor suppressor belongs to the SOX F gene subfamily and is associated with a variety of human cancers, including breast cancer, but the mechanisms involved are largely unclear. In the current study, we investigated the interactions between SOX7 and AXIN2 in their co-regulation on the Wnt/β-catenin signal pathway, using clinical specimens and microarray gene expression data from the GEO database, for their roles in breast cancer. We compared the expression levels of SOX7 and other co-expressed genes in the Wnt/β-catenin pathway and found that the expression of SOX7, SOX17 and SOX18 was all reduced significantly in the breast cancer tissues compared to normal controls. AXIN2 had the highest co-relativity with SOX7 in the Wnt/β-catenin signaling pathway. Clinicopathological analysis demonstrated that the down-regulated SOX7 was significantly correlated with advanced stages and poorly differentiated breast cancers. Consistent with bioinformatics predictions, SOX7 was correlated positively with AXIN2 and negatively with β-catenin, suggesting that SOX7 and AXIN2 might play important roles as co-regulators through the Wnt-β-catenin pathway in the breast tissue to affect the carcinogenesis process. Our results also showed Smad7 as the target of SOX7 and AXIN2 in controlling breast cancer progression through the Wnt/β-catenin signaling pathway.

Breast cancer is the most common malignancy in women around the world, and its incidence and mortality rates are still rising. An increasing number of studies have reported that SOX18 plays an important role in various cancers. However, the role of SOX18 in breast cancer remains poorly understood. In this study, we aimed to investigate the biological role and potential molecular mechanism of SOX18 in breast cancer. We found that the mRNA and protein expression levels of SOX18 were prevalently and significantly overexpressed in human breast cancer cell lines. Next, we performed loss-of-function experiments by transfection of two breast cancer cell lines, BT-474 and MCF-7, with SOX18 small interfering RNAs (siRNA). Results showed that SOX18 siRNA transfection significantly suppressed mRNA and protein expression of SOX18 in breast cancer cells. Furthermore, knockdown of SOX18 significantly inhibited cell proliferation and invasion, but promoted apoptosis in breast cancer cells. Importantly, several oncogenic proteins, including the Ras homolog gene family member A (RhoA), platelet-derived growth factor B (PDGFB), Insulin-like growth factor 1 receptor (IGF-1R), and matrix metalloproteinase-7 (MMP-7), were markedly decreased by SOX18 siRNA. Taken together, the results of our study suggest that knockdown of SOX18 inhibits breast cancer cell growth and invasion, possibly by downregulating downstream oncogenic proteins, providing novel insights into the development of breast cancer therapy through targeting of SOX18.

Sex determining region Y‑box 18 (SOX18) has been found to be overexpressed in several types of tumor. However, the molecular mechanism underlying the biological function of SOX18 in osteosarcoma remains to be elucidated. The present study aimed to elucidate the roles of SOX18 in regulating the biological behavior of osteosarcoma cells. First, SOX18 mRNA expression was analyzed in osteosarcoma tissues using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). The results demonstrated that the expression of SOX18 was elevated in osteosarcoma tissue, compared with normal bone tissue. In addition, the knockdown of SOX18 in U2OS or MG63 osteosarcoma cells inhibited cell proliferation and significantly increased the population of cells in the S‑phase of the cell cycle, as measured by the CCK‑8 assay and flow cytometric analysis, respectively. Additionally, suppression of the expression of SOX18 in the osteosarcoma cells significantly induced cell apoptosis as evaluated by annexin V/propidium iodide staining and flow cytometric analysis. The downregulation of SOX18 was found to significantly inhibit cell adhesion and invasion. The mRNA and protein expression levels of transforming growth factor‑β, platelet‑derived growth factor (PDGF)‑A, PDGF‑B and RhoA were also reduced by SOX18 silencing, as assessed by RT‑qPCR and western blot analysis, respectively. These results indicated that SOX18 may function as an oncogene, and may provide a novel and promising therapeutic strategy for osteosarcoma.

The c-Myc gene codes for a basic-helix-loop-helix-leucine zipper transcription factor protein and is reported to be frequently over-expressed in human cancers. Given that c-Myc plays an essential role in neoplastic transformation we wished to define its activity in lung cancer and therefore studied its targeted expression to respiratory epithelium in a transgenic mouse disease model. Using histological well-defined tumors, transcriptome analysis identified novel c-Myc responsive cell cycle and apoptosis genes that were validated as direct c-Myc targets using EMSA, Western blotting, gene reporter and ChIP assays.Through computational analyses c-Myc cooperating transcription factors emerged for repressed and up-regulated genes in cancer samples, namely Klf7, Gata3, Sox18, p53 and Elf5 and Cebpα, respectively. Conversely, at promoters of genes regulated in transgenic but non-carcinomatous lung tissue enriched binding sites for c-Myc, Hbp1, Hif1 were observed. Bioinformatic analysis of tumor transcriptomic data revealed regulatory gene networks and highlighted mortalin and moesin as master regulators while gene reporter and ChIP assays in the H1299 lung cancer cell line as well as cross-examination of published ChIP-sequence data of 7 human and 2 mouse cell lines provided strong evidence for the identified genes to be c-Myc targets. The clinical significance of findings was established by evaluating expression of orthologous proteins in human lung cancer. Taken collectively, a molecular circuit for c-Myc-dependent cellular transformation was identified and the network analysis broadened the perspective for molecularly targeted therapies.

Naked cuticle homolog2 (NKD2) is located in chromosome 5p15.3, which is frequently loss of heterozygosity in human colorectal and gastric cancers. In order to understand the mechanism of NKD2 in gastric cancer development, 6 gastric cancer cell lines and 196 cases of human primary gastric cancer samples were involved. Methylation specific PCR (MSP), gene expression array, flow cytometry, transwell assay and xenograft mice model were employed in this study. The expression of NKD1 and NKD2 was silenced by promoter region hypermethylation. NKD1 and NKD2 were methylated in 11.7% (23/196) and 53.1% (104/196) in human primary gastric cancer samples. NKD2 methylation is associated with cell differentiation, TNM stage and distant metastasis significantly (all P < 0.05), and the overall survival time is longer in NKD2 unmethylated group compared to NKD2 methylated group (P < 0.05). Restoration of NKD2 expression suppressed cell proliferation, colony formation, cell invasion and migration, induced G2/M phase arrest, and sensitized cancer cells to docetaxel. NKD2 inhibits SOX18 and MMP-2,7,9 expression and suppresses BGC823 cell xenograft growth. In conclusion, NKD2 methylation may serve as a poor prognostic and chemo-sensitive marker in human gastric cancer. NKD2 impedes gastric cancer metastasis by inhibiting SOX18.

Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world. Recent studies have demonstrated that SOX18 is highly expressed in various types of cancer. In the present study, we found that SOX18 mRNA was overexpressed in HCC compared with non-tumorous tissues. We aimed to explore the effects of SOX18 siRNA on the proliferation, invasion and migration of two HCC cell lines, MHCC97H and HepG2, which overexpress SOX18. We found that SOX18 siRNA significantly inhibited the proliferation and induced cell cycle arrest at the G0/G1 phase. Results of the Transwell assay showed that the migration and invasion of the HCC cells were markedly impaired in the SOX18-knockdown cells. Gene set enrichment analysis (GSEA) showed that KEGG focal adhesion and chemokine signaling pathways were correlated with SOX18 expression. Furthermore, the mRNA and protein levels of RhoA, PDGFB, IGF1R, CCL2, CCL3 and CCL5 were decreased in the SOX18-knockdown cells. Importantly, we demonstrated that upregulation of SOX18 was associated with a poor outcome in HCC patients. These results indicate that SOX18 may serve as a prognostic factor and a promising therapeutic strategy for HCC.

Recent studies have demonstrated the involvement of SOX18 transcription factor in blood and lymphatic vessel development, as well as in wound healing processes. SOX18 expression has been noted in cancer cells of various tumours, including lung cancer. However, the exact role of SOX18 expression in non-small cell lung cancer (NSCLC) remains to be determined. The present study, therefore, assessed its expression in 198 cases of NSCLC, consisting of 94 adenocarcinomas (AC), 89 squamous cell carcinomas (SQC) and 15 large cell carcinomas (LCC). The analysis utilized immunohistochemistry (IHC) and, in 42 cases, molecular methods. SOX18 expression was also determined in NSCLC cell lines (NCI-H1703, NCI-H522 and A549) and in normal lung fibroblasts (IMR-90). SOX18 was found to be expressed in nuclei, as well as in the cytoplasm of cancer cells, in the majority of studied cases. SOX18 mRNA expression was significantly lower in NSCLC than in non-malignant lung tissue (p<0.0001). However, SOX18 protein expression levels were higher in NSCLC tissues (p<0.005) and in the examined lung cancer cell lines. No SOX18 expression was noted in the IMR-90 cell line. In paraffin sections, a positive correlation between the Ki-67 antigen and nuclear SOX18 expression (r=0.17, p<0.05) was noted. In univariate survival analysis, cytoplasmic SOX18 expression correlated with poor patient outcome in the whole study and in AC cohorts (both p<0.05). Based on these results, SOX18 may be involved in the progression of NSCLC.

PURPOSE: SOX18 is a transcription factor known to be involved in hair follicle, blood and lymphatic vessel development, as well as wound healing processes (together with SOX7 and SOX17). In addition, it has been reported that SOX18 may affect the growth of cancer cells in vitro. Until now, the exact role of SOX18 expression in invasive ductal breast carcinoma (IDC) has remained unknown.
METHODS: In this study, we have investigated SOX18 expression in cancer cells and endothelial cells in 122 IDC samples using immunohistochemistry (IHC). SOX18 expression was also determined using real-time PCR and Western blotting in a series of breast cancer-derived cell lines (i.e., MCF-7, BT-474, SK-BR-3, MDA-MB-231, BO2).
RESULTS: Using IHC, we observed SOX18 nuclear expression in cancer cells, as well as in blood and lymphatic vessels of the IDC samples tested. SOX18 expression in the IDC samples correlated with a higher malignancy grade (Grade 2 and Grade 3 versus Grade 1; p = 0.02 and p = 0.009, respectively) and VEGF-D expression (r = 0.27, p = 0.007). SOX18 expression was also associated with HER2 positivity (p = 0.02). A significantly higher SOX18 expression was found in the HER2-positive cell line BT-474, and a significantly lower expression in the triple negative cell lines MDA-MB-231 and BO2. Laser capture microdissection of IDC samples revealed significantly higher mRNA SOX7, SOX17 and SOX18 expression levels in the vessels as compared to the cancer cells (p = 0.02 and p = 0.0002, p < 0.0001, respectively). SOX18 positive intratumoral and peritumoral microvessel counts (MVC) were associated with higher malignancy grades (p = 0.04 and p = 0.02, respectively). Moreover, peritumoral SOX18 positive MVC were found to act as an independent marker for a poor prognosis (p = 0.04).
CONCLUSION: SOX18 expression may serve as a marker for a poor prognosis in IDC.

Our goal of this study was to reconstruct a "genome-scale co-expression network" and find important modules in lung adenocarcinoma so that we could identify the genes involved in lung adenocarcinoma. We integrated gene mutation, GWAS, CGH, array-CGH and SNP array data in order to identify important genes and loci in genome-scale. Afterwards, on the basis of the identified genes a co-expression network was reconstructed from the co-expression data. The reconstructed network was named "genome-scale co-expression network". As the next step, 23 key modules were disclosed through clustering. In this study a number of genes have been identified for the first time to be implicated in lung adenocarcinoma by analyzing the modules. The genes EGFR, PIK3CA, TAF15, XIAP, VAPB, Appl1, Rab5a, ARF4, CLPTM1L, SP4, ZNF124, LPP, FOXP1, SOX18, MSX2, NFE2L2, SMARCC1, TRA2B, CBX3, PRPF6, ATP6V1C1, MYBBP1A, MACF1, GRM2, TBXA2R, PRKAR2A, PTK2, PGF and MYO10 are among the genes that belong to modules 1 and 22. All these genes, being implicated in at least one of the phenomena, namely cell survival, proliferation and metastasis, have an over-expression pattern similar to that of EGFR. In few modules, the genes such as CCNA2 (Cyclin A2), CCNB2 (Cyclin B2), CDK1, CDK5, CDC27, CDCA5, CDCA8, ASPM, BUB1, KIF15, KIF2C, NEK2, NUSAP1, PRC1, SMC4, SYCE2, TFDP1, CDC42 and ARHGEF9 are present that play a crucial role in cell cycle progression. In addition to the mentioned genes, there are some other genes (i.e. DLGAP5, BIRC5, PSMD2, Src, TTK, SENP2, PSMD2, DOK2, FUS and etc.) in the modules.

OBJECTIVE: The aim of this study was to identify novel genes following genomic DNA copy number changes using a genome-wide array-based comparative genomic hybridization (array-CGH) analysis in uterine leiomyosarcoma (ULMS).
METHODS: Genomic DNA copy number changes were analyzed in 15 cases of ULMS from St Mary's Hospital of the Catholic University of Korea. The paraffin-fixed tissue samples were micro-dissected under microscope, and DNA was extracted. Array-based CGH and genomic polymerase chain reaction were carried out with statistical analyses such as hierarchical clustering and Gene Ontology.
RESULTS: All of 15 cases of ULMS showed specific gains and losses. The percentage of average gains and losses were 8.4 and 16.6 %, respectively. The analysis limit of average gains and losses was 40 %. The regions of high level of gain were 1q23.3, 7p14.2, 7q34, 7q35, 7q36.3, 13q34, and 16p13.3. And the regions of homozygous loss were 2q21.1, 2q22.1, 2p23.2, 12q23.3, 4q21.22, 4q34.3, 11q24.2, 12q23.3, 13q13.1, 13q21.33, and 14q24.3. In ULMS samples, recurrent regions of gain were 1p36.33, 1p36.32, 5q35.3, 7q36.3, and 8q24.3 and recurrent regions of loss were 1p31.1-p31.3, 1p32.1-p32.3, 2p12, 2p13.3, 2p14, 2p16.2-p16.3, 2q12.1-q12.3, 2q21.1-q21.2, 2q22.2-q22.3, 2q34, 2q36.1-q36.3, 5q21.3, 5q23.3, 5q31.1, 6p11.2, 6p12.1, 10q11.23, 10q21.2-q21.3, 10q23.2, 10q23.31, 10q25.1-q25.2, 10q25.3, 10q26.13, 10q26.2-q26.3, 11p11.2, 11p11.12, 11p12, 11p13, 11p15.4, 11q23.1-q23.2, 11q23.3, 13q14.12, 13q14.13-13q14.2, 13q14.2, 13q14.2, 13q14.3, 13q21.33, 13q22.1-q22.3, 14q24.2, 14q24.3, 14q31.1, 14q32.33, 15q11.2-q13, 15q14, 16q22.3, 16q23.1, 16q23.2, 16q24.1, 20p12.1, and 21q22.3. Representative frequently gained BAC clones encoded genes were HDAC9, CRR9, SOX18, PTPRN2, SKI, SOLH, and KIAA1199. The genes encoded by frequently lost BAC clones were LOC150516 and AMY2A. A subset of cellular processes from each gene were clustered by Gene Ontology database.
CONCLUSIONS: The present study using array-CGH analyses sought a deeper elucidation of the specific genomic alterations related to ULMS. The high resolution of array-CGH combined with human genome database would give a chance at identifying relevant target genes.

BACKGROUND: Known risk factors for secondary lymphedema only partially explain who develops lymphedema following cancer, suggesting that inherited genetic susceptibility may influence risk. Moreover, identification of molecular signatures could facilitate lymphedema risk prediction prior to surgery or lead to effective drug therapies for prevention or treatment. Recent advances in the molecular biology underlying development of the lymphatic system and related congenital disorders implicate a number of potential candidate genes to explore in relation to secondary lymphedema.
METHODS AND RESULTS: We undertook a nested case-control study, with participants who had developed lymphedema after surgical intervention within the first 18 months of their breast cancer diagnosis serving as cases (n=22) and those without lymphedema serving as controls (n=98), identified from a prospective, population-based, cohort study in Queensland, Australia. TagSNPs that covered all known genetic variation in the genes SOX18, VEGFC, VEGFD, VEGFR2, VEGFR3, RORC, FOXC2, LYVE1, ADM, and PROX1 were selected for genotyping. Multiple SNPs within three receptor genes, VEGFR2, VEGFR3, and RORC, were associated with lymphedema defined by statistical significance (p<0.05) or extreme risk estimates (OR <0.5 or >2.0).
CONCLUSIONS: These provocative, albeit preliminary, findings regarding possible genetic predisposition to secondary lymphedema following breast cancer treatment warrant further attention for potential replication using larger datasets.

We used methylation-sensitive high resolution melting analysis to assess methylation of CpG islands within the promoters of the TIMP4, GATA4, SOX18, and EGFL7 genes in samples of non-small cell lung cancer and surrounding apparently normal tissue and noncancerous lung tissues. We found that the promoter methylation was heterogeneous in both tumor and surrounding normal tissue. This is in contrast to healthy lung tissue, where the promoters were normally either non- or hypomethylated, and the heterogeneity of methylation was low. An increased heterogeneity of methylation in the normal tissues surrounding the tumor may suggest an early start of epigenetic processes preceding genetic and morphologic changes and can be used as a biomarker of early cancerization events. This analysis is an easy and sensitive tool for studying epigenetic heterogeneity and could be used in clinical practice.

BACKGROUND: SOX2 is a key gene implicated in maintaining the stemness of embryonic and adult stem cells. SOX2 appears to re-activate in several human cancers including glioblastoma multiforme (GBM), however, the detailed response program of SOX2 in GBM has not yet been defined.
RESULTS: We show that knockdown of the SOX2 gene in LN229 GBM cells reduces cell proliferation and colony formation. We then comprehensively characterize the SOX2 response program by an integrated analysis using several advanced genomic technologies including ChIP-seq, microarray profiling, and microRNA sequencing. Using ChIP-seq technology, we identified 4883 SOX2 binding regions in the GBM cancer genome. SOX2 binding regions contain the consensus sequence wwTGnwTw that occurred 3931 instances in 2312 SOX2 binding regions. Microarray analysis identified 489 genes whose expression altered in response to SOX2 knockdown. Interesting findings include that SOX2 regulates the expression of SOX family proteins SOX1 and SOX18, and that SOX2 down regulates BEX1 (brain expressed X-linked 1) and BEX2 (brain expressed X-linked 2), two genes with tumor suppressor activity in GBM. Using next generation sequencing, we identified 105 precursor microRNAs (corresponding to 95 mature miRNAs) regulated by SOX2, including down regulation of miR-143, -145, -253-5p and miR-452. We also show that miR-145 and SOX2 form a double negative feedback loop in GBM cells, potentially creating a bistable system in GBM cells.
CONCLUSIONS: We present an integrated dataset of ChIP-seq, expression microarrays and microRNA sequencing representing the SOX2 response program in LN229 GBM cells. The insights gained from our integrated analysis further our understanding of the potential actions of SOX2 in carcinogenesis and serves as a useful resource for the research community.

BACKGROUND: Loss of CD9 expression has been correlated with a higher motility and metastatic potential of tumour cells originating from different organs. However, the mechanism underlying this loss is not yet understood.
METHODS: We produced a truncated form of partner 1 of CD9 (CD9P-1), GS-168AT2, and developed a new monoclonal antibody directed towards the latter. We measured the expression of CD9 and CD9P-1 in human lung tumours (hLTs), and monitored the level of CD9 in NCI-H460, in vitro and in vivo, in the presence and absence of GS-168AT2.
RESULTS: Loss of CD9 is inversely related to the expression of CD9P-1, which correlates with the metastatic status of hLT (n=55). In vitro, GS-168AT2 is rapidly internalised and degraded at both the membrane and cytoplasm of NCI-H460, and this correlates with the association of GS-168AT2 with both CD9 and CD81. Intraperitoneal injections of GS-168AT2 in NCI-H460-xenografted Nude mice led to drastic inhibition of tumour growth, as well as to the downregulation of CD9, but not of CD81, in the tumour core.
CONCLUSION: These findings show for the first time that CD9P-1 expression positively correlates with the metastatic status of hLT, and that the upregulation of CD9P-1 expression could be one of the mechanisms underlying the loss of CD9 in solid tumours. Our study also reveals that, under certain conditions, loss of CD9 could be a tumour growth-limiting phenomenon rather than a tumour growth-promoting one.

Over 10 years have passed since the first Sox gene was implicated in melanocyte development. Since then, we have discovered that SOX5, SOX9, SOX10 and SOX18 all participate as transcription factors that affect key melanocytic genes in both regulatory and modulatory fashions. Both SOX9 and SOX10 play major roles in the establishment and normal function of the melanocyte; SOX10 has been shown to heavily influence melanocyte development and SOX9 has been implicated in melanogenesis in the adult. Despite these advances, the precise cellular and molecular details of how these SOX proteins are regulated and interact during all stages of the melanocyte life cycle remain unknown. Improper regulation of SOX9 or SOX10 is also associated with cancerous transformation, and thus understanding the normal function of SOX proteins in the melanocyte will be key to revealing how these proteins contribute to melanoma.

BACKGROUND: The growth of solid tumors depends on establishing blood supply; thus, inhibiting tumor angiogenesis has been a long-term goal in cancer therapy. The SOX18 transcription factor is a key regulator of murine and human blood vessel formation.
METHODS: We established allograft melanoma tumors in wild-type mice, Sox18-null mice, and mice expressing a dominant-negative form of Sox18 (Sox18RaOp) (n = 4 per group) and measured tumor growth and microvessel density by immunohistochemical analysis with antibodies to the endothelial marker CD31 and the pericyte marker NG2. We also assessed the affects of disrupted SOX18 function on MCF-7 human breast cancer and human umbilical vein endothelial cell (HUVEC) proliferation by measuring BrdU incorporation and by MTS assay, cell migration using Boyden chamber assay, and capillary tube formation in vitro. All statistical tests were two-sided.
RESULTS: Allograft tumors in Sox18-null and Sox18RaOp mice grew more slowly than those in wild-type mice (tumor volume at day 14, Sox18 null, mean = 486 mm3, 95% confidence interval [CI] = 345 mm3 to 627 mm3, P = .004; Sox18RaOp, mean = 233 mm3, 95% CI = 73 mm3 to 119 mm3, P<.001; versus wild-type, mean = 817 mm3, 95% CI = 643 mm3 to 1001 mm3) and had fewer CD31- and NG2-expressing vessels. Expression of dominant-negative Sox18 reduced the proliferation of MCF-7 cells (BrdU incorporation: MCF-7(Ra) = 20%, 95% CI = 15% to 25% versus MCF-7 = 41%, 95% CI = 35% to 45%; P = .013) and HUVECs (optical density at 490 nm, empty vector, mean = 0.46 versus SOX18 mean = 0.29; difference = 0.17, 95% CI = 0.14 to 0.19; P = .001) compared with control subjects. Overexpression of wild-type SOX18 promoted capillary tube formation of HUVECs in vitro, whereas expression of dominant-negative SOX18 impaired tube formation of HUVECs and the migration of MCF-7 cells via the disruption of the actin cytoskeleton.
CONCLUSIONS: SOX18 is a potential target for antiangiogenic therapy of human cancers.

Genetic factors play a critical role in the pathogenesis of vascular anomalies. Significant advances have been made in recent years in identifying the genetic and molecular determinants of a variety of vascular anomalies using a molecular genetic approach. Several genes for vascular anomalies have been identified. These genes include AGGF1 for Klippel-Trenaunay syndrome, RASA1 for capillary malformations, KRIT1, MGC4607, PDCD10 for cerebral cavernous malformations, glomulin for glomuvenous malformations, TIE2 for multiple cutaneous and mucosal venous malformations, VEGFR-3, FOXC2, NEMO, SOX18 for lymphedema or related syndromes, ENG, ACVRLK1, MADH4 for HHT or related syndromes, NDP for Coats' disease, Notch3 for CADASIL, and PTEN for Proteus Syndrome. These findings have made genetic testing possible in some clinical cases, and may lead to the development of therapeutic strategies for vascular anomalies. Furthermore, these studies have identified critical genes involved in vascular morphogenesis, and provided fundamental understanding of the molecular mechanisms underlying vasculogenesis and angiogenesis.

PURPOSE: Using a genome-wide array-based comparative genomic hybridization (array-CGH), DNA copy number changes in uterine leiomyosarcoma were analyzed.
MATERIALS AND METHODS: We analyzed 4 cases of uterine leiomyoma and 7 cases of uterine leiomyosarcoma. The paraffin-fixed tissue samples were microdissected under microscope and DNA was extracted. Array-based CGH and fluorescence in situ hybridization (FISH) were carried out with Genome database (Gene Ontology).
RESULTS: Uterine leiomyoma showed no genetic alterations, while all of 7 cases of uterine leiomyosarcoma showed specific gains and losses. The percentage of average gains and losses were 4.86% and 15.1%, respectively. The regions of high level of gain were 7q36.3, 7q33-q35, 12q13-12q15, and 12q23.3. And the regions of homozygous loss were 1p21.1, 2p22.2, 6p11.2, 9p21.1, 9p21.3, 9p22.1, 14q32.33, and 14q32.33 qter. There were no recurrent regions of gain, but recurrent regions of loss were 1p21.1-p21.2, 1p22.3-p31.1, 9p21.2-p22.2, 10q25-q25.2, 11q24.2-q25, 13q12-q12.13, 14q31.1-q31.3, 14q32.32-q32.33, 15q11-q12, 15q13-q14, 18q12.1-q12.2, 18q22.1-q22.3, 20p12.1, and 21q22.12-q22.13. In the high level of gain regions, BAC clones encoded HMGIC, SAS, MDM2, TIM1 genes. Frequently gained BAC clone-encoded genes were TIM1, PDGFR-beta, REC Q4, VAV2, FGF4, KLK2, PNUTL1, GDNF, FLG, EXT1, WISP1, HER-2, and SOX18. The genes encoded by frequently lost BAC clones were LEU1, ERCC5, THBS1, DCC, MBD2, SCCA1, FVT1, CYB5, and ETS2/E2. A subset of cellular processes from each gene was clustered by Gene Ontology database.
CONCLUSION: Using array-CGH, chromosomal aberrations related to uterine leiomyosarcoma were identified. The high resolution of array-CGH combined with human genome database would give a chance to find out possible target genes present in the gained or lost clones.

In this study, microarray analysis was used to identify tumour-related genes that were down regulated in lung carcinoma. The promoter sequences of the identified genes were analysed for methylation patterns. In lung cancer cell lines, CpG island methylation was frequently detected for TIMP4 (64%), SOX18 (73%), EGF-like domain 7 (56%), CD105 (71%), SEMA2 (55%), RASSF1A (71%), p16 (56%) SLIT2 (100%) and TIMP3 (29%). Methylation was however rarely observed in cell lines for SLIT3 (18%) and DLC1 (18%). In primary lung tumours, methylation of TIMP4 (94%), SOX18 (100%), EGF-like domain 7 (100%), CD105 (69%), SEMA2 (93%), DLC1 (61%), RASSF1A (44%), p16 (47%), SLIT2 (100%) and TIMP3 (13%) was also detected. Methylation of several CpG islands was frequently found in normal lung tissue of cancer patients and this may have been attributed to epigenetic field defect and/or infiltrating tumour cells. Interestingly, inactivation of RASSF1A and p16 correlated well with an extended smoking habit (P=0.02), and exposure to asbestos (P=0.017) or squamous cell carcinoma (P=0.011), respectively. These results have identified genes whose aberrant promoter methylation could play a crucial role in the malignancy of lung carcinoma.

SOX proteins are a family of transcription factors with high-mobility-group DNA-binding domain (HMG box) homologous to SRY, which play key roles in embryogenesis. Xenopus Sox17alpha, Sox17beta, Sox3 and mouse Sox7 are reported to be negative regulators of the WNT-beta-catenin-TCF signaling pathway. SOX7, SOX17, and SOX18 constitute a subfamily among the SOX gene family. Here, expression of SOX18 mRNA was investigated using Northern blot analysis, RNA dot blot analysis, and cDNA-PCR. SOX18 mRNA was significantly highly expressed in ventricles and inter-ventricular septum of adult heart among various normal human tissues. SOX18 mRNA was relatively highly expressed in stomach and jejunum in the gastrointestinal tract. SOX18 mRNA was relatively highly expressed in TMK1 and MKN45 among 7 gastric cancer cell lines. SOX18 mRNA was expressed in all out of 7 pancreatic cancer cell lines, and was relatively highly expressed in PANC-1, Hs700T, Hs766T and MIA PaCa-2. Expression level of SOX18 mRNA in MCF-7 cells (breast cancer) was not affected by beta-estradiol. SOX18 mRNA was expressed in all out of 5 embryonal tumor cell lines, and was relatively highly expressed in NT2 with the potential to differentiate into neuronal cells. Expression level of SOX18 mRNA in NT2 cells was down-regulated by all-trans retinoic acid. This is the first report on comprehensive expression analyses of SOX18 mRNA in normal human tissues and tumors.

SOX transcription factors with high-mobility-group DNA-binding domain (HMG box) play key roles in embryogenesis. Some members of the SOX family are negative regulators of the WNT-beta-catenin-TCF signaling pathway. We have previously cloned and characterized human SOX17, constituting a subfamily with SOX7 and SOX18. Another group mapped SOX7 gene to human chromosome 8p22, and reported almost ubiquitous expression of 5.0-kb SOX7 mRNA in human normal tissues. Here, expression of SOX7 mRNA was investigated by using SOX7 specific probe, which hybridized to 3.8-kb human SOX7 mRNA, but not to 5.0-kb mRNA. SOX7 mRNA was relatively highly expressed in adult lung, trachea, lymph node, placenta, fetal lung, and heart. In adult heart, SOX7 mRNA was more highly expressed in ventricules, inter-ventricular septum and apex than in atriums. SOX7 mRNA was significantly up-regulated in pancreatic cancer cell lines BxPC-3, PSN-1, Hs766T, and in 4 cases out of 8 cases of primary gastric cancer. SOX7 mRNA was relatively highly expressed in a gastric cancer cell line MKN45, esophageal cancer cell lines TE2, TE3, TE4, TE5, TE7, TE8, TE11, TE12, and TE13. On the other hand, SOX7 mRNA was significantly down-regulated in 7 out of 18 cases of primary colorectal tumors, in 4 out of 9 cases of primary breast cancer, in 4 out of 14 cases of primary kidney tumors, and also in some cases of primary lung and prostate cancer. SOX7 gene might be one of cancer-associated genes on human chromosome 8p22.