RG108 induces the apoptosis of endometrial cancer Ishikawa cell lines by inhibiting the expression of DNMT3B and demethylation of HMLH1.

OBJECTIVE: The effects of DNA methyltransferase (DNMT) inhibitor RG108 on the proliferation and apoptosis of endometrial cancer was investigated, and whether its mechanism was related to the inhibition of DNMT3B, thereby affecting the human mutL homolog 1 (hMLH1) methylation status and its expression, was further studied. MATERIALS AND METHODS: Culture of human endometrial cancer Ishikawa cell lines: cells grew adhering to the wall in Roswell Park Memorial Institute-1640 (RPMI-1640) medium (supplemented with 10% fetal bovine serum (FBS) and 2 mM L-glutamic acid). After the cells were treated with RG108, the changes in cell viability were detected via methyl thiazolyl tetrazolium (MTT) assay. The effect of RG108 on cell cycle was detected via flow cytometry, and its effect on cell apoptosis was detected via flow cytometry and TUNEL. Moreover, the methylation status of hMLH1gene in endometrial cancer cells was detected via methylation specific-PCR (MSP), and the changes in DNMT3Band hMLH1 expressions were detected via RT-PCR and Western blotting, respectively. RESULTS: MTT results showed that RG108 inhibited the cell viability in a dose-dependent and time-dependent manner. Flow cytometry revealed that RG108 blocked the cell cycle in G2/M phase and promoted the apoptosis, and TUNEL assay further proved that RG108 promoted the apoptosis. It was found in the detection via MSP that the methylated hMLH1 gene was significantly reduced after 72 h of treatment with RG108. Besides, RT-PCR and Western blotting showed that RG108 inhibited the DNMT3B expression and activated the hMLH1 expression. CONCLUSIONS: The demethylation drug RG108 can significantly inhibit the proliferation of endometrial cancer cells, block the cell cycle in the G2/M phase and induce the cell apoptosis, which is a new candidate drug in the treatment of endometrial cancer. RG108 realizes the hMLH1 demethylation and increases the hMLH1 expression through inhibiting the expression of DNMT3B.

MiR-133b regulates the expression of CTGF in epithelial-mesenchymal transition of ovarian cancer.

OBJECTIVE: To explore the role of miR-133b in ovarian cancer and to preliminarily elucidate the mechanism of miR-133b in epithelial-mesenchymal transition (EMT) of ovarian cancer. PATIENTS AND METHODS: MiR-133b was detected in ovarian cancer specimens, and the relationship of miR-133b with each pathological index and clinical index of ovarian cancer was analyzed. The action targets of miR-133b in ovarian cancer were analyzed systematically and studied deeply via the target validation and cell function validation. Finally, the possible reasons of ovarian cancer metastasis were analyzed through the molecular regulation mechanism in EMT of ovarian cancer. RESULTS: The miR-133b level in ovarian cancer was significantly lower than in normal ovarian tissues and benign ovarian tumors (p<0.05). The level of miR-133b in ovarian cancer was related to differentiated degree and lymphatic metastasis. Dual-luciferase assay indicated that connective tissue growth factor (CTGF) was the target gene regulated by miR-133b. Reverse transcriptase-polymerase chain reaction (RT-PCR) as well as Western blot results proved that the expression level of E-cadherin representing the epithelial cell phenotype was increased, while the expression level of vimentin representing the mesenchymal cell phenotype was decreased. Transwell assay confirmed that the migration and invasion abilities of ovarian cancer cells declined after transfection with miR-133b plasmid. After co-transfection with miR-133b and CTGF overexpression plasmids, RT-PCR and Western blotting proved that the expression level of E-cadherin representing the epithelial cell phenotype was decreased, while the expression level of vimentin representing the mesenchymal cell phenotype was increased; transwell assay confirmed that the cell migration and invasion abilities were increased after co-transfection. CONCLUSIONS: The results of this study showed that miR-133b may serve as a new molecular marker of EMT of ovarian cancer, and act as a molecular marker of differentiated degree and lymphatic metastasis of ovarian cancer.

[Application of new chest holder in the median sternotomy for open heart surgery in adults].

Objective: To explore the application of new chest holder in the median sternotomy for open heart surgery in adults. Methods: Two hundred adult patients in Henan Provincial People's Hospital from May 2013 to May 2015 were enrolled in the study and randomly divided into two groups. Experimental group included 100 cases who accepted the new type of chest holder in the open heart surgery. Control group were also composed of 100 cases whose sternums were fixed with the pure steel wire cerclage. Sternal closure time was recorded since the sternum closing. All subjects were followed up to obtain the chest incision healing, the incidence of sternal dehiscence, infection and secondary thoracotomy, and thus to estimated the effect of new chest holder. Results: All patients in the experimental group reached the effect of firm closed chest surgery. Sternal closure time of experimental group was much shorter than that of control group[(10±2) vs (21±4) min, P<0.001]. No sternal instability, dehiscence, infection and secondary thoracotomy were found during the follow-up. However, in the control group, 3 secondary thoracotomy cases, 6 sternal dehiscence cases and 2 sternal infection cases were detected. Conclusions: New type of chest holder in the median sternotomy for open heart surgery is more convenient with small surgical trauma. It can also effectively reduce the incidence of sternal instability, dehiscence, infection and secondary thoracotomy.