Dataset Information

Grhl3 induces human epithelial tumor cell migration and invasion via downregulation of E-cadherin.

ABSTRACT: Grainyhead genes are involved in wound healing and developmental neural tube closure. Metastasis is a multistep process during which cancer cells disseminate from the site of primary tumors and establish secondary tumors in distant organs. The adhesion protein E-cadherin plays an essential role in metastasis. In light of the high degree of similarity between the epithelial-mesenchymal transition (EMT) occurring in wound-healing processes and the EMT occurring during the acquisition of invasiveness in skin or breast cancer, we investigated the role of the Grainyhead genes in cancer invasion. Here, we show that there is an inverse relationship between Grainyhead-like 3 (Grhl3) and E-cadherin expression in some epithelial tumor cell lines. Overexpression of Grhl3 in the E-cadherin-positive epithelial tumor cell line, characterized by less invasiveness, generated a transcriptional blockage of the E-cadherin gene and promoted cell migration and cell invasion. Conversely, Grhl3 depletion inhibited cell migration and cell invasion and was associated with a gain of E-cadherin expression. To further explore the mechanism by which Grhl3 regulated E-cadherin expression, an E-cadherin promoter report analysis was performed and results showed that Grhl3 repressed E-cadherin gene expression by directly or indirectly binding to the E-boxes present in the proximal E-cadherin promoter. Taken together, our findings define a major role for Grhl3 in the induction of migration and invasion by the downregulation of E-cadherin in cancer cells.

SUBMITTER: Zhao P

PROVIDER: S-EPMC4885135 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Ovarian cancer (OC) is the second leading cause of gynecological cancer death worldwide. Although the list of biomarkers is still growing, molecular mechanisms involved in OC development and progression remain elusive. We recently demonstrated that lower expression of the molecular chaperone TRAP1 in OC patients correlates with higher tumor grade and stage, and platinum resistance. Herein we show that TRAP1 is often deleted in high-grade serous OC patients (N=579), and that TRAP1 expression is correlated with the copy number, suggesting this could be one of the driving mechanisms for the loss of TRAP1 expression in OC. At molecular level, downregulation of TRAP1 associates with higher expression of p70S6K, a kinase frequently active in OC with emerging roles in cell migration and tumor metastasis. Indeed, TRAP1 silencing in different OC cells induces upregulation of p70S6K expression and activity, enhancement of cell motility and epithelial-mesenchymal transition (EMT). Consistently, in a large cohort of OC patients, TRAP1 expression is reduced in tumor metastases and directly correlates with the epithelial marker E-Cadherin, whereas it inversely correlates with the transcription factor Slug and the matrix metallopeptidases 2 and 9. Strikingly, pharmacological inhibition of p70S6K reverts the high motility phenotype of TRAP1 knock-down cells. However, although p70S6K inhibition or silencing reduces the expression of the transcription factors Snail and Slug, thus inducing upregulation of E-Cadherin expression, it is unable to revert EMT induced by TRAP1 silencing; furthermore, p70S6K did not show any significant correlation with EMT genes in patients, nor with overall survival or tumor stage, suggesting an independent and predominant role for TRAP1 in OC progression. Altogether, these results may provide novel approaches in OC with reduced TRAP1 expression, which could be resistant to therapeutic strategies based on the inhibition of the p70S6K pathway, with potential future intervention in OC invasion and metastasis.

Project description:α-Hispanolol (α-H) is a labdane diterpenoid that has been shown to induce apoptosis in several human cancer cells. However, the effect of α-H in human glioblastoma cells has not been described. In the present work, we have investigated the effects of α-H on apoptosis, migration, and invasion of human glioblastoma cells with the aim of identifying the molecular targets underlying its mechanism of action. The results revealed that α-H showed significant cytotoxicity against human glioma cancer cell lines U87 and U373 in a concentration- and time-dependent manner. This effect was higher in U87 cells and linked to apoptosis, as revealed the increased percentage of sub-G1 population by cell cycle analysis and acquisition of typical features of apoptotic cell morphology. Apoptosis was also confirmed by significant presence of annexin V-positive cells and caspase activation. Pretreatment with caspase inhibitors diminishes the activities of caspase 8, 9, and 3 and maintains the percentage of viable glioblastoma cells, indicating that α-H induced cell apoptosis through both the extrinsic and the intrinsic pathways. Moreover, we also found that α-H downregulated the anti-apoptotic Bcl-2 and Bcl-xL proteins and activated the pro-apoptotic Bid and Bax proteins. On the other hand, α-H exhibited inhibitory effects on the migration and invasion of U87 cells in a concentration-dependent manner. Furthermore, additional experiments showed that α-H treatment reduced the enzymatic activities and protein levels of matrix metalloproteinase MMP-2 and MMP-9 and increased the expression of TIMP-1 inhibitor, probably via p38MAPK regulation. Finally, xenograft assays confirmed the anti-glioma efficacy of α-H. Taken together, these findings suggest that α-H may exert anti-tumoral effects in vitro and in vivo through the inhibition of cell proliferation and invasion as well as by the induction of apoptosis in human glioblastoma cells. This research describes α-H as a new drug that may improve the therapeutic efficacy against glioblastoma tumors.

Dataset Information

Grhl3 induces human epithelial tumor cell migration and invasion via downregulation of E-cadherin.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets