Knockdown of GRHL3 Inhibits Activities and Induces Cell Cycle Arrest and Apoptosis of Human Colorectal Cancer Cells

The Grainyhead-like 3（GRHL3） is involved in epidermal barrier formation, neural tube closure and wound repair. Previous studies have suggested that GRHL3 has been linked to many different types of cancers. However, to date, its effects on human colorectal cancer（CRC） has not been clarified yet. Our microarray analysis has indicated predominant GRHL3 expression in CRC. The purpose of this study was to investigate the expression and significance of GRHL3 in CRC tumorigenesis using CRC tissues and paired paracancerous tissues, as well as using distinct CRC cell lines（HT29 and DLD1）. We observed increased GRHL3 expression at both m RNA and protein levels in CRC tissues and CRC cell lines using quantitative real-time polymerase chain reaction（q RT-PCR） and Western blotting. Moreover, silencing GRHL3 with si RNA could suppress CRC cell proliferation, viability and migration in vitro. We also found that knockdown of GRHL3 could promote cell cycle arrest at G0/G1 phase in HT29 cells and DLD1 cells, and induce cell apoptosis in HT29 cells. Together, our study revealed the down-regulation of GRHL3 in vitro could inhibit CRC cell activity and trigger cell cycle arrest at G0/G1 phase and apoptosis.

High mobility group-box 3 overexpression is associated with poor prognosis of resected gastric adenocarcinoma

AIM:To elucidate high mobility group-box 3(HMGB3) protein expression in gastric adenocarcinoma,its potential prognostic relevance,and possible mechanism of action.METHODS:Ninety-two patients with gastric adenocarcinomas surgically removed entered the study.HMGB3 expression was determined by immunohistochemistry through a tissue microarray procedure.The clinicopathologic characteristics of all patients were recorded,and regular follow-up was made for all patients.The inter-relationship of HMGB3 expression with histological and clinical factors was analyzed using nonparametric tests.Survival analysis was carried out by Kaplan-Meier(log-rank) and multivariate Cox(Forward LR) analyses between the group with overexpression of HMGB3 and the group with low or no HMGB3 ex-pression to determine the prognosis value of HMGB3 expression on overall survival.Further,HMGB3 expression was knocked down by small hairpin RNAs(shRNAs) in the human gastric cancer cell line BGC823 to observe its influence on cell biological characteristics.The MTT method was utilized to detect gastric cancer cell proliferation changes,and cell cycle distribution was analyzed by flow cytometry.RESULTS:Among 92 patients with gastric adenocarcinomas surgically removed in this study,high HMGB3 protein expression was detected in the gastric adenocarcinoma tissues vs peritumoral tissues(P < 0.001).Further correlation analysis with patients' clinical and histology variables revealed that HMGB3 overexpression was obviously associated with extensive wall penetration(P = 0.005),a positive nodal status(P = 0.004),and advanced tumor-node-metastasis(TNM) stage(P = 0.001).But there was no correlation between HMGB3 overexpression and the age and gender of the patient,tumor localization or histologic grade.Statistical Kaplan-Meier survival analysis disclosed significant differences in overall survival between the HMGB3 overexpression group and the HMGB3 no or low expression group(P = 0.006).The expected overall survival time was 31.00 ± 3.773 mo(95%CI = 23.605-38.395) for patients with HMGB3 overexpression and 49.074 ± 3.648 mo(95%CI = 41.925-57.311) for patients with HMGB3 no and low-level expression.Additionally,older age(P = 0.040),extensive wall penetration(P = 0.008),positive lymph node metastasis(P = 0.005),and advanced TNM tumor stage(P = 0.007) showed negative correlation with overall survival.Multivariate Cox regression analysis indicated that HMGB3 overexpression was an independent variable with respect to age,gender,histologic grade,extent of wall penetration,lymph nodal metastasis,and TNM stage for patients with resectable gastric adenocarcinomas with poor prognosis(hazard ratio = 2.791,95%CI = 1.233-6.319,P = 0.019).In the gene function study,after HMGB3 was knocked down in the gastric cell line BGC823 by shRNA,the cell proliferation rate was reduced at 24 h,48 h and 72 h.Compared to BGC823 shRNA-negative control(NC) cells,the cell proliferation rate in cells that had HMGB3 shRNA transfected was significantly decreased(P < 0.01).Finally,cell cycle analysis by FACS showed that BGC823 cells that had HMGB3 knocked down were blocked in G1/G0 phase.The percentage of cells in G1/G0 phase in BGC823 cells with shRNA-NC and with shRNA-HMGB3 was 46.84% ± 1.7%,and 73.03% ± 3.51% respectively(P = 0.001),whereas G2/M cells percentage decreased from 26.51% ± 0.83% to 17.8% ± 2.26%.CONCLUSION:HMGB3 is likely to be a useful prognostic marker involved in gastric cancer disease onset and progression by regulating the cell cycle.

Cellular metabolic energy modulation by tangeretin in 7,12-dimethylbenz(a) anthracene-induced breast cancer

Breast cancer is the leading cause of death among women worldwide.Chemoprevention and chemotherapy play beneficial roles in reducing the incidence and mortality of cancer.Epidemiological and experimental studies showed that naturally-occurring antioxidants present in the diet may act as anticancer agents.Identifying the abnormalities of cellular energy metabolism facilitates early detection and management of breast cancer.The present study evaluated the effect of tangeretin on cellular metabolic energy fluxes in 7,12-dimethylbenz（a）anthracene（DMBA）-induced proliferative breast cancer.The results showed that the activities of glycolytic enzymes significantly increased in mammary tissues of DMBA-induced breast cancer bearing rats.The gluconeogenic tricarboxylic acid（TCA） cycle and respiratory chain enzyme activities significantly decreased in breast cancer-bearing rats.In addition,proliferating cell nuclear antigen（PCNA） was highly expressed in breast cancer tissues.However,the activities of glycolytic enzymes were significantly normalized in the tangeretin pre- and post-treated rats and the TCA cycle and respiratory chain enzyme activities were significantly increased in tangeretin treated rats.Furthermore,tangeretin down-regulated PCNA expression on breast cancerbearing rats.Our study demonstrates that tangeretin specifically regulates cellular metabolic energy fluxes in DMBA-induced breast cancer-bearing rats.

Flow Cytometry Analysis of Cellular DNA Content of the Parotid Pleomorphic Adenoma

The nuclear DNA content in 42 cases of primary parotid pleomorphic adenoma (PPA) and 15 cases of recurrent PPA were analysed with flowcytometer (FCM) to study the correlation of the DNA index (DI), S% and cellular proliferous index (PI) with the biologic behaivor of the tumor. The results indicated that in a portion of pleomorphic adenoma, the nuclear DNA content had altered and possessed malignant potential before any evidence of malignancy could be found under lightmicroscope. The increase of S% and PI, which followed the course of tumor development, has a close relation with the capsular invasion and the recurrence. There was a significant difference on the DI, S%, PI as well as the incidence of heteroploid between the recurrent and the incipient tumor. A great portion of recurrent tumors, which still diagnosed as benign pathologically, was acually heteroploid.

Effects of insulin-like growth factor binding protein 7 on cell cycle and proliferation of gastric cancer in vitro and in vivo

Objective To investigate the effects of insulin-like growth factor binding protein 7(IGFBP7)on the proliferation,cell cycle of gastric cancer cell and the expression of cynlin D1,cyclin-dependent kinase(CDK)4,and to observe the effects of IGFBP7 on the growth of gastric tumor xenografts in nude mice.Methods The MKN-28cell line was interfered by small interfere ribonucleic acid(siRNA)(interfered group),and blank control group,