6934

TCF7L2

transcription factor 7-like 2 (T-cell specific, HMG-box);TCF7L2;transcription factor 7-like 2 (T-cell specific, HMG-box)

HMG box transcription factor 4|T-cell factor 4|T-cell factor-4 variant A|T-cell factor-4 variant B|T-cell factor-4 variant C|T-cell factor-4 variant D|T-cell factor-4 variant E|T-cell factor-4 variant F|T-cell factor-4 variant G|T-cell factor-4 variant H|

10q25.3

protein-coding

The goal of this study was to identify genes related to the metastasis of clear cell renal cell carcinoma (CRCC). We analyzed copy number alterations in renal tissue specimens of patients with CRCC patients with or without metastasis by using high-resolution single-nucleotide polymorphism (SNP) arrays and then integrated these data with gene expression profiling data obtained using oligonucleotide microarrays. The expression levels of target genes were determined by quantitative real-time RT-PCR (qRT-PCR) with an independent tumor set. An analysis of specimens from 23 CRCC cases with SNP arrays revealed that hemizygous deletions at 10q and 13q were found only in cases of metastatic disease. We found the homozygous deletion of TCF7L2 at 10q25.2 in an aggressive case that had hemizygous deletions at 10q. In addition, a qRT-PCR analysis of TCF7L2 mRNA levels in tumor samples revealed significantly lower levels in patients with metastasis when compared with those without metastasis. FOXO1 was identified as a down-regulated gene in the minimal overlapping region of the 13q hemizygous deletion in CRCC. Decreased FOXO1 expression was significantly correlated with metastasis and poor survival outcome. Knockdown of FOXO1 inhibited apoptosis after doxorubicin treatment in CRCC cells and reduced the expression of downstream genes involved in cell proliferation (CDKN1B) and survival (BCL2L11). Lower levels of FOXO1 expression were associated with decreased expression of CDKN1B and BCL2L11 in CRCC specimens. We conclude that FOXO1 and TCF7L2 are involved in metastasis and that molecules in these signaling pathways may be targets for diagnostic procedures and therapies for CRCC.

AIM: Hepatocellular carcinoma(HCC) is a significant health problem in China. But the molecular mechanisms of HCC remains unclear. APC/beta-Catenin/Tcf signaling pathway, also known as Wnt pathway, plays a critical role in the development and oncogenesis. As little is known about the alteration of human T-cell transcription factor-4 (hTcf-4) gene in HCC, it is of interest to study the expression and mutation of hTcf-4 gene in HCC and the relationship between hTcf-4 gene and progression of HCC. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) method was used to detect the expression of hTcf-4 mRNA in 32 HCC and para-cancerous tissues and 5 normal liver tissues. PCR-single strand conformation polymorphism (PCR-SSCP) method was used to detect the mutation of hTcf-4 exons 1, 4, 9 and 15 in HCC. The correlation of expression and mutation of the hTcf-4 gene with clinicopathological characteristics of HCC was also analyzed. RESULTS: RT-PCR showed that the expression rate of hTcf-4 mRNA in HCC, para-cancerous tissues and normal liver tissues was 90.6 %, 71.9 % and 80 %, respectively. The gene expression level in tumor was 0.71+/-0.13, much higher than that in para-cancerous liver 0.29+/-0.05 and normal liver 0.26+/-0.05 (P<0.001), although there was no significant difference in gene expression level between para-cancerous tissues and normal liver (P>0.05). Furthermore, hTcf-4 gene expression was closely associated with tumor capsule status and intrahepatic metastasis of HCC. On SSCP, 2 of 32 cases of HCC (6.25 %) displayed characteristic mutational mobility shifts in exon 15 of the hTcf-4 gene. No abnormal shifting bands were observed in para-cancerous tissues. CONCLUSION: The high expression level of hTcf-4 in HCC, especially in tumors with metastasis, suggests that the over-expression of hTcf-4 gene may be closely associated with development and progression of HCC, but the mutation of this gene seemed to play less important role in this respect.

An essential function of the transcription factors LEF1/TCF4 in cerebral metastases of lung adenocarcinomas has been described in mouse models, suggesting a WNT/beta-catenin effect as potential mechanism. Their role in humans is still unclear, thus we analyzed LEF1, TCF4, beta-catenin, and early stage prognostic markers in 25 adenocarcinoma brain metastases using immunohistochemistry (IHC). IHC revealed nuclear TCF4 in all adenocarcinoma samples, whereas only 36 % depicted nuclear LEF1 and nuclear beta-catenin signals. Samples with nuclear LEF1 as well as high TCF4 (++++) expression were associated with a shorter survival (p = 0.01, HR = 6.68), while nuclear beta-catenin had no significant impact on prognosis and did not significantly correlate with nuclear LEF1. High proliferation index Ki67 was associated with shorter survival in late-stage disease (p = 0.03, HR 3.27). Additionally, we generated a LEF1/TCF4 as well as an AXIN2 signature, the latter as representative of WNT/beta-catenin activity, following a bioinformatics approach with a gene expression dataset of cerebral metastases in lung adenocarcinoma. To analyze the prognostic relevance in primary lung adenocarcinomas, we applied both signatures to a microarray dataset of 58 primary lung adenocarcinomas. Only the LEF1/TCF4 signature was able to separate clusters with impact on survival (p = 0.01, HR = 0.32). These clusters displayed diverging enrichment patterns of the cell cycle pathway. In conclusion, our data show that LEF1/TCF4, but not beta-catenin, have prognostic relevance in primary and cerebrally metastasized human lung adenocarcinomas. In contrast to the previous in vivo findings, these results indicate that LEF1/TCF4 act independently of beta-catenin in this setting.