Association of ERBB4 genetic polymorphism with the risk and prognosis of non-small cell lung cancer in Chinese Han population: A population-based case-control study.

ABSTRACT: The aim of this study was to explore the association of rs1836724 single-nucleotide polymorphism (SNP) of ERBB4 with risk and prognosis of non-small cell lung cancer (NSCLC) in the Chinese Han population.The genotype of rs1836724 SNP of ERBB4 from 258 patients with NSCLC and 200 noncancer controls were detected the TaqMan-MGB probes real-time fluorescence polymerase chain reaction. The distribution of genotype and alleles between the 2 groups was compared, and the association between clinicopathological characteristic and rs1836724 SNP was analyzed. Prognosis and influencing factors were analyzed by Kaplan-Meier and Cox regression analysis.There were significant differences in the genotype and allele distribution of ERBB4 rs1836724 between the NSCLC group and control group (P < .05). And CC genotype of rs1836724 was associated with increased risk of NSCLC in the Chinese Han population. Rs1836724 SNP was associated with TNM stage and lymph nodal metastasis (P = .001, P = .007). The median follow-up was 29 months, and the progression-free survival and overall survival of 258 NSCLC patients were 27.91% and 31.39%, respectively. Patients with GG genotype of rs1836724 had poor progression-free survival and overall survival. Rs1836724 SNP was an independent prognostic marker of NSCLC patients, CC genotype had a high risk of poor prognosis (odds ratio = 1.587, 95% confidence interval: 1.079-2.335, P = .019).In Chinese Han populations, rs1836724 SNP of ERBB4 may contribute toward the increased risk and poor prognosis of NSCLC.

Overexpression of polo-like kinase 1 and its clinical significance in human non-small cell lung cancer.

Polo-like kinase 1 is a serine/threonine kinase which plays an essential role in mitosis and malignant transformation. The aim of this study was to investigate the prognostic significance of polo-like kinase 1 expression and determine its possibility as a therapeutic target in non-small cell lung cancer. Semi-quantitative RT-PCR assay was performed to detect polo-like kinase 1 mRNA expression in non-small cell lung cancer cells or tissues. Immunohistochemistry was performed to detect polo-like kinase 1 protein expression in 100 non-small cell lung cancer tissue samples, and the associations of polo-like kinase 1 expression with clinicopathological factors or prognosis of non-small cell lung cancer patients were evaluated. RNA interference was employed to inhibit endogenous polo-like kinase 1 expression and analyzed the effects of polo-like kinase 1 inhibition on the malignant phenotypes of non-small cell lung cancer cells including growth, apoptosis, radio- or chemoresistance. Also, the possible molecular mechanisms were also investigated. The levels of polo-like kinase 1 mRNA expression in non-small cell lung cancer cell lines or tissues were significantly higher than those in normal human bronchial epithelial cell line or corresponding non-tumor tissues. High polo-like kinase 1 expression was significantly correlated with advanced clinical stage, higher tumor classification and lymph node metastasis of non-small cell lung cancer patients (P=0.001, 0.004 and 0.001, respectively). Meanwhile, high polo-like kinase 1 protein expression was also an independent prognostic molecular marker for non-small cell lung cancer patients (hazard ratio: 2.113; 95% confidence interval: 1.326-3.557; P=0.017). Polo-like kinase 1 inhibition could significantly inhibit in vitro and in vivo proliferation, induce cell arrest of G(2)/M phase and apoptosis enhancement in non-small cell lung cancer cells, which might be activation of the p53 pathway and the Cdc25C/cdc2/cyclin B1 feedback loop. Further, inhibition of polo-like kinase 1 could enhance the sensitivity of non-small cell lung cancer cells to taxanes or irradiation. Thus, polo-like kinase 1 might be a prognostic marker and a chemo- or radiotherapeutic target for non-small cell lung cancer.

Prognostic significance of serum miRNA-21 expression in human non-small cell lung cancer.

BACKGROUND: Deregulation of microRNAs (miRNAs) plays important roles in tumor progression. The aim of this study was to investigate miR-21 expression in serum of non-small cell lung cancer (NSCLC) and its correlation with prognosis of NSCLC patients. METHODS: Dysregulated miRNAs in NSCLC serum were identified by microarray. MiR-21 expression in NSCLC and control serum was detected by TaqMan RT-PCR assay. The correlation of serum miR-21 with clinicopathological factors of NSCLC patients was analyzed. Furthermore, the prognostic significance of serum miR-21 was analyzed by using Kaplan-Meier curves with log-rank tests and a Cox proportional hazard model. RESULTS: The level of miR-21 expression was higher in NSCLC serum samples than in control serum samples (P < 0.01). High serum miR-21 was significantly correlated with tumor-node metastases stage and lymph node metastasis of NSCLC patients (P = 0.016 and 0.026, respectively). The 3-year actuarial overall survival rates in NSCLC patients with high serum miR-21 expression (39.8%) was significantly shorter than those with low serum miR-21 expression (58.2%; P < 0.001). Furthermore, univariate and multivariate analyses for overall survival showed that serum miR-21 expression was an independent prognostic factor for NSCLC patients (P = 0.015, RR = 2.01, 95% CI: 1.78-3.26). CONCLUSION: Serum miR-21 expression might be useful as a prognostic marker for NSCLC patients.

Upregulation of microRNA-451 increases cisplatin sensitivity of non-small cell lung cancer cell line (A549).

BACKGROUND: Recently, miR-451 as a tumor suppressor has been reported in other studies. However, whether miR-451 can affect the sensitivity of non-small cell lung cancer (NSCLC) cells to cisplatin (DDP) remains unclear. The aim of this study is to evaluate the roles of miR-451 in the sensitivity of NSCLC cells to DDP. METHODS: Quantitative RT-PCR assay was performed to detect the expression of miR-451 in 10 pairs of NSCLC and noncancerous tissue samples. pcDNA-GW/EmGFP-miR-451 was stably transfected into NSCLC cell line (A549). Then, the effects of miR-451 upregulation on growth, colony formation and apoptosis of A549 cells were investigated. Finally, the effects of miR-451 upregulation on in vitro and in vivo sensitivity of A549 cells of DDP were also determined. RESULTS: The level of miR-451 expression in NSCLC tissues was significantly higher than that in corresponding noncancerous tissues. Ectopic overexpression of miR-451 could significantly inhibit growth and induce apoptosis of A549 cells. Moreover, ectopic overexpression of miR-451 could sensitize A549 cells to DDP possibly by increasing DDP-induced apoptosis which might be associated with the inactivation of Akt signaling pathway. CONCLUSIONS: This study demonstrated for the first time that combination of DDP application with miR-451 upregulation might be a potential strategy for the treatment of human NSCLC.

Adenovirus-mediated suicide gene therapy under the control of Cox-2 promoter for colorectal cancer.

Colorectal cancer is a most frequent type of gastrointestinal tract cancers. The prognosis of patients with colorectal cancer remains poor despite intensive interventions. Tumor specific promoter-directed gene therapy and adenoviral technology can be promising strategies for such advanced disease. This study was conducted to explore the possible therapeutic approach of Cox-2 promoter-directed suicide gene therapy with herpes simplex virus thymidine kinase (HSV-tk) in combination with adenoviral technology for advanced colorectal cancer. Firstly, the activity of Cox-2 promoter was assessed by dual luciferase and enhanced green fluorescent protein reporter gene assays in colorectal cancer cell lines and normal human intestinal epithelial cell line. Then, the expression of coxsackievirus and adenovirus receptor (CAR) was detected in colorectal cancer cell lines. The Cox-2 promoter-directed HSV-tk/ganciclovir (GCV) system mediated by adenovirus (Ad-Cp-TK) was developed (Ad-CMVp-TK, Ad-null and no Ad as controls). In vitro cytoxicity, colony formation and apoptosis assays were performed using Ad-Cp-TK. An animal study was carried out in which BALB/C nude mice bearing tumors were treated with Ad-Cp-TK and GCV treatments. Results showed that Cox-2 promoter possessed high transcriptional activity in a tumor-specific manner. All colorectal cancer cells were detected CAR-positive. In vitro cytotoxic and colony formation assays showed that colorectal cancer cells infected with Ad-Cp-TK became more sensitive to GCV but the sensitivity of normal cells infected with Ad-Cp-TK to GCV were not altered. Moreover, the Ad-Cp-TK system combined with GCV treatment could significantly induce apoptosis of colorectal cancer cells but not normal intestinal epithelial cells. Furthermore, this system also significantly inhibited the growth of subcutaneous tumors and prolonged survival of mice. Thus, adenovirus primary receptor was positive in colorectal cancer cells and adenovirus-mediated suicide gene therapy under the control of Cox-2 promoter could provide a promising treatment modality for advanced colorectal cancer with tumor specificity.