• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.16
• /
• pp.7255-7260
• /
• 2015

Background: Recent reports have shown that DLC-1 is widely expressed in normal tissues and is down-regulated in a wide range of human tumors, suggesting it may act as a tumor suppressor gene. We conducted a meta-analysis to determine the correlation between DLC-1 expression and clinicopathological characteristics in cancers. Materials and Methods: A detailed literature search was made for relevant publications from PubMed, EMBASE, Cochrane library databases, Web of Science, CNKI. The methodological quality of the studies was also evaluated. Analyses of pooled data were performed and odds ratios (ORs) were calculated and summarized. Results: Final analysis was performed of 1,815 cancer patients from 19 eligible studies. We observed that DLC- 1 expression was significantly lower in cancers than in normal tissues. DLC-1 expression was not found to be associated with tumor differentiation status. However, DLC-1 expression was obviously lower in advance stage than in early-stage cancers and was more down-regulated in metastatic than non-metastatic cancers. Conclusions: The results of our meta-analysis suggested that DLC-1 expression is significantly lower in cancers than in normal tissues. Aberrant DLC-1 expression may play an important role in cancer genesis and metastasis.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.4
• /
• pp.1231-1233
• /
• 2012

Objective: The aim of this study was to explore the expression of DLC-l in breast carcinoma and any association with tumor metastasis. Methods: 51 surgical specimens of human breast carcinoma, divided into high invasive and low invasive groups according to their clinicopathological features, 30 cases of adjacent normal tissue and 28 benign breast lesions were examined by qRT-PCR for expression of DLC-1. Results: Expression level of DLC-1 in adjacent normal tissue and benign breast lesion specimens was higher than that in breast carcinoma (P<0.0001); the values in the high invasive group with synchronous metastases were also lower than in the low invasive group (P=0.0275). The correlation between DLC-1 expression level and tumor progression and metastasis of breast cancer was negative. Conclusion: As an anti-oncogene, DLC-1 could play an important part in breast carcinoma occurrence, progression, invasiveness and metastasis. Detecting the changes of the expression of DLC-1 in the breast carcinoma may contribute to earlier auxiliary diagnosis of invasiveness, metastasis and recrudescence.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.4
• /
• pp.1637-1642
• /
• 2015

Background: RhoGTPase-activating proteins (RhoGAPs) regulate RhoGTPases in cells, but whether individual reactive oxygen species (ROS) regulate RhoGAPs is unknown. Our previous published papers have shown that deleted in liver cancer 1 (DLC1) inhibits cancer cell migration by its RhoGAP activity. The present study was designed to explore the role of $H_2O_2$ in regulation of DLC1. Materials and Methods: We treated cells with $H_2O_2$ for 24h and phenotypic changes were analyzed by MTT, RT-PCR, Western blotting, immunofluorescence staining and wound healing assays. Results: $H_2O_2$ downregulated cyclin D1 and cyclin E to inhibit proliferation, and upregulated BAX to induce apoptosis in MCF-7 cells. Compared with non-tumorigenic cells, $H_2O_2$ increased expression of DLC1 and reduced activity of RhoA in cancer cells. Stress fiber production and migration were also suppressed by $H_2O_2$ in MDA-MB-231 cells. Conclusions: Our study suggests that $H_2O_2$ inhibits proliferation through modulation of cell cycle and apoptosis-related genes, and inhibits migration by decreasing stress fibers via DLC1/RhoA signaling.