117581

TWIST2

twist family bHLH transcription factor 2;TWIST2;twist family bHLH transcription factor 2

class A basic helix-loop-helix protein 39|dermis-expressed protein 1|twist basic helix-loop-helix transcription factor 2|twist homolog 2|twist-related bHLH protein Dermo1|twist-related protein 2

2q37.3

protein-coding

BACKGROUND: Adenoid cystic carcinoma (ACC) of salivary gland is characterized by advanced local invasion and distant metastasis. Intratumoral hypoxia was reported to be associated with epithelial-mesenchymal transition (EMT) regulators. The purpose of this study was to evaluate the relationship between hypoxia-inducible factor (HIF)-2alpha, TWIST2, and SIP1 expression and the invasion and metastasis in ACC of salivary gland. METHOD: In vitro we first detected the expression of HIF-2alpha, TWIST2, and SIP1 in two ACC cell lines by Western blot and real-time RT-PCR. Then, in vivo, a retrospective investigation of 121 patients with ACC from Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology, Sichuan University between 1996 and 2005 was carried out using immunohistochemistry to analyze the association between the expression of these three factors and clinical-pathological factors of patients. RESULTS: The protein and mRNA levels of HIF-2alpha, TWIST2, and SIP1 in the high-metastasis cell line (ACC-M) were much higher than those of the low-metastasis cell line (ACC-2). The positive expression of HIF-2alpha, TWIST2, and SIP1 (71.07%, 42.98%, and 38.02%, respectively) was associated with the perineural invasion, the local recurrence, and distant metastasis of patients with ACC (P < 0.05). The patients with the positive coexpression of the three factors had a lower survival rate than those with the negative expression (P < 0.05). CONCLUSION: It is proposed that the elevated expression of HIF-2alpha, TWIST2, and SIP1 can contribute to invasion and metastasis of ACC, and there might be some correlation between the hypoxia microenvironment and EMT in ACC.

OBJECTIVE: Globally, cervical cancer is the second most common cancer among women, and determining potential targets involved in tumor progression is necessary. This study investigated the clinic-pathological significance of twist homolog 2 (TWIST2), a basic helix-loop-helix transcription factor, and correlated TWIST2 and E-cadherin expression in cervical cancer. METHODS: A series of 142 samples, including 14 cases of normal cervical tissues, 58 cases of cervical intraepithelial neoplasia (CIN) and 70 cases of squamous cell carcinoma (SCC), were examined TWIST2 and E-cadherin immunohistochemical staining and statistical analysis. RESULTS: Increased cytoplasmic and nuclear expression levels of TWIST2 were associated with the malignant transformation of cervical epithelium and the histological progression of cervical cancer. A logistic test showed that TWIST2 was a relatively independent predictor of lymph node metastasis of SCC. Further, increased levels of TWIST2 were also associated with aberrant expression of E-cadherin, an important EMT indicator. CONCLUSIONS: The present data suggest that TWIST2 overexpression was significantly linked to cervical cancer progression, which makes it a promising marker for determining the metastatic potential of cervical cancer, and up-regulation of TWIST2, in combination with aberrant E-cadherin expression in primary cervical cancer tissues, may predict the malignant transformation and distal metastasis of carcinomas.

BACKGROUND: Colorectal cancer (CRC) is the most common digestive system malignancy. The molecular events involved in the development and progression of CRC remain unclear. Recently, more and more evidences have showed that deregulated miRNAs participate in colorectal carcinogenesis. METHODS: The expression levels of miR-138 were first examined in CRC cell lines and tumor tissues by real-time PCR. The in vitro and in vivo functional effects of miR-138 were examined further. Luciferase reporter assays were conducted to confirm the targeting associations. Kaplan-Meier analysis and log-rank tests were performed to estimate the overall survival and disease free survival rate. RESULTS: miR-138 was found to be down-regulated in human colorectal cancer tissues and cell lines. Ectopic expression of miR-138 resulted in a dramatic inhibition of CRC migration and invasion in vitro and in vivo. Twist basic helix-loop-helix transcription factor 2 gene (TWIST2) was identified as one of the functional target. Restoration of miR-138 resulted in a dramatic reduction of the expression of TWIST2 at both mRNA and protein levels by directly targeting its 3-untranslated region (3UTR). Up-regulation of TWIST2 was detected in CRC tumors compared with adjacent normal tissues (P < 0.001) and is inversely correlated with miR-138 expression. We also identified that down-regulation of miR-138 was associated with lymph node metastasis, distant metastasis, and always predicted poor prognosis. CONCLUSION: These data highlight a pivotal role for miR-138 in the regulation of CRC metastasis by targeting TWIST2, and suggest a potential application of miR-138 in prognosis prediction and CRC treatment.

Twist1 and Twist2 are major regulators of embryogenesis. Twist1 has been shown to favor the metastatic dissemination of cancer cells through its ability to induce an epithelial-mesenchymal transition (EMT). Here, we show that a large fraction of human cancers overexpress Twist1 and/or Twist2. Both proteins override oncogene-induced premature senescence by abrogating key regulators of the p53- and Rb-dependent pathways. Twist1 and Twist2 cooperate with Ras to transform mouse embryonic fibroblasts. Interestingly, in epithelial cells, the oncogenic cooperation between Twist proteins and activated mitogenic oncoproteins, such as Ras or ErbB2, leads to complete EMT. These findings suggest an unanticipated direct link between early escape from failsafe programs and the acquisition of invasive features by cancer cells.

BACKGROUND: Twist2 has been shown to promote human tumor invasion as in breast cancer and cervical cancer. However, whether Twist2 promotes human ovarian cancer progression remains to be elucidated. Here, we investigate the role of Twist2 in ovarian cancer invasion and metastasis as well as the underlying molecular mechanisms. METHODS: Twist2 expression was detected by Immunohistochemistry (IHC) on tissue microarray of human ovarian cancers with scoring procedure according to the staining intensity and pattern. Twist2 gene was stably introduced into SKOV-3 ovarian cancer cells to examine the changes of cellular morphology, motility, invasiveness, and EMT molecular markers. RESULTS: Twist2 expression is significantly increased in ovarian cancers along with the FIGO disease stage, indicating that Twist2 may be associated with ovarian cancer metastasis. Overexpression of Twist2 induced the EMT phenotype including downregulation of E-cadherin, and upregulation of N-cadherin and beta-catenin in human ovarian cancer cells, suggesting that Twist2 might promote beta-catenin release from the E-cadherin/beta-catenin complex through inhibition of E-cadherin. Thus, beta-catenin degradation was inhibited due to inhibition of APC, and the Wnt/beta-catenin pathway was then activated by nuclear beta-catenin accumulation, which may activate transcription of downstream target genes to promote tumor invasion and metastasis. Collectively, these data indicated that beta-catenin is involved in Twist2-induced EMT in ovarian cancer. CONCLUSION: Our data indicates that upregulation of Twist2 is correlated with the FIGO stage in human ovarian cancers. In this report, we demonstrated that nuclear beta-catenin is accumulated in Twist2-induced EMT cells to facilitates ovarian cancer invasion and metastasis.