ABSTRACT
BACKGROUND: Colorectal cancer (CRC) is one of the most common gastrointestinal malignancies. LncRNA CASC15 has also been found to play a vital role in malignant tumors. OBJECTIVE: Our objective is to explore the role of CASC15 in colorectal cancer and its regulation of EMT and to clarify the reasons for its up-regulated expression in CRC. METHODS: Quantitative real-time PCR was performed to evaluate the expression of CASC15 in CRC. The biology function of CASC15 on CRC was assessed by in vitro experiments, including CCK8, colony formation, transwell assays and flow cytometry. Luciferase reporter assays were used to confirm the regulation between TCF12 and CASC15. Quantitative real-time PCR and western blot analysis were used to evaluate the biomarkers associated with epithelial-mesenchymal transition (EMT). RESULTS: We found that CASC15 was remarkably upregulated in CRC and positively correlated with poorer relapse-free survival. CASC15 knockdown significantly suppressed the proliferation and migration of CRC. Furthermore, CASC15 downregulation mediated apoptosis of CRC. Mechanistically, TCF12 activates CASC15 transcription to mediate its up-regulation, which activates EMT and promotes CRC progression. CONCLUSION: Our study identified TCF12/CASC15/EMT as a new regulatory signal axis of CRC. CASC15 may be a new molecular marker and target for CRC.
ABSTRACT
Association between the epithelial growth factor receptor (EGFR) mutation and the expression of breast cancer 1 (BRCA1) and receptor-associated protein 80 (RAP80) in non-small cell lung cancer (NSCLC) was studied. From September 2014 to September 2016, 51 patients with NSCLC who were hospitalized in Department of Thoracic Surgery in The Affiliated Jiangyin Hospital of Southeast University Medical College and underwent biopsy or operation were selected. The pathological changes of lung tissue were detected by hematoxylin and eosin histopathological staining. The fluorescent expression of BRCA1 and RAP80 protein in the two groups was determined by immunofluorescence staining. Reverse transcriptase polymerase chain reaction method and western blot analysis were used to detect BRCA1 and RAP80 mRNA and protein expression. Then the EGFR gene mutation was detected and analyzed. The results show that non-small cell lung cancer has an association with smoking. Compared with the control, the lung tissue structure of the NSCLC group was damaged. The protein fluorescence expression of BRCA1 and RAP80 in non-small cell lung cancer group was significantly increased. The expression of BRCA1 and RAP80 mRNA and protein in NSCLC group was significantly increased. The difference in expression of BRCA1 and RAP80 in the control and the non-small cell lung cancer group was statistically significant (P<0.05). EGFR gene mutations detected 14 of the 51 patients with genetic mutations. Non-small cell lung cancer and smoking have certain relevance, and BRCA1 and RAP80 expression in the development and progression of NSCLC has a close relationship. EGFR mutation in non-small cell lung cancer significantly related to the mutation of EGFR and BRCA1 and RAP80 gene expression plays an important role in the diagnosis and treatment of NSCLC.
ABSTRACT
The abnormal expression of Tau protein in breast cancer tissue affects paclitaxel sensitivity. The abnormal expression also exists in gastric carcinoma. Therefore, we speculate that the expression levels of Tau protein is closely related to paclitaxel sensitivity in gastric cancer, thus affecting the efficacy of paclitaxel. In this study, we used immunohistochemical methods to detect Tau protein expression levels in 47 cases of gastric cancer specimens. We also used Western blot to detect the level of Tau protein expression in gastric cancer cell lines and to check the efficacy of paclitaxel in vitro application. Findings indicate that Tau protein expression rate can reach as high as (+ +-+ + +) 63.83 % in gastric cancer. Paclitaxel induces inhibition and apoptosis with low expression of Tau protein in gastric cancer cell lines (P < 0.05). The level of Tau protein expression is significantly correlated with paclitaxel efficacy. If confirmed by further studies, the Tau protein can be another useful marker of gastric cancer, thereby leading to the application of paclitaxel in cancer treatment.