Gastric cancer is the fourth most common malignancy and the third leading cause of cancer-related deaths worldwide. Advanced gastric cancer patients can notably benefit from chemotherapy including adriamycin, platinum drugs, 5-fluorouracil, vincristine, and paclitaxel as well as targeted therapy drugs. Nevertheless, primary drug resistance or acquisition drug resistance eventually lead to treatment failure and poor outcomes of the gastric cancer patients. The detailed mechanisms involved in gastric cancer drug resistance have been revealed. Interestingly, different noncoding RNAs (ncRNAs), such as microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), are critically involved in gastric cancer development. Multiple lines of evidences demonstrated that ncRNAs play a vital role in gastric cancer resistance to chemotherapy reagents and targeted therapy drugs. In this review, we systematically summarized the emerging role and detailed molecular mechanisms of ncRNAs impact drug resistance of gastric cancer. Additionally, we propose the potential clinical implications of ncRNAs as novel therapeutic targets and prognostic biomarkers for gastric cancer.

To investigate the role of PTEN and matrix metalloproteinase-7 (MMP-7) expression in tumorigenesis and progression of gastric carcinoma, their expression in 113 gastric carcinomas was studied by immunohistochemistry. Microvessel density (MVD) was counted using the anti-CD34 antibody. The expressions of PTEN and MMP-7, and MVD were compared with the clinicopathological parameters of tumors, and the relationship between PTEN and MMP-7 expression and MVD was analyzed. It was found that PTEN was expressed less frequently in primary gastric carcinoma cells than in adjacent epithelial cells (P < 0.05), whereas this was reversed for MMP-7 (P < 0.05). PTEN expression was negatively correlated with invasion, metastasis, growth pattern, Lauren's classification and histological classification (P < 0.05). Matrix metalloproteinase-7 expression was positively associated with tumor size, Borrmann's classification, invasive depth, metastasis and TNM staging (P < 0.05), but negative with PTEN expression (P < 0.05). A positive correlation of MVD with tumor size, invasive depth, metastasis and TNM staging was found (P < 0.05). Microvessel density depended on decreased PTEN expression and increased MMP-7 expression (P < 0.05). The results of the present study suggested that down-regulated PTEN expression and up-regulated MMP-7 expression were greatly implicated in tumorigenesis and progression of gastric carcinoma. Close correlation between PTEN on MMP-7 expression provided a novel insight into the regulatory effects of PTEN on MMP-7 expression in gastric carcinoma.

To estimate the distribution of lymphoid neoplasms in China, we conducted a comprehensive analysis, based on subtype, age, sex, and lesion, of primary and resected biopsy specimens of 4,638 lymphoid neoplasms diagnosed from 2004 to 2008 at 5 large hospitals. Of the 4,638 patients, mature B-cell neoplasms accounted for 64.3% of all lymphoid neoplasms, mature T/NK-cell neoplasms for 23.3%, and Hodgkin lymphoma for 8.6%. The most common subtype was diffuse large B-cell lymphoma (36.2%), followed by extranodal NK/T-cell lymphoma, nasal type (11.0%), classic Hodgkin lymphoma (8.4%), extranodal marginal zone B-cell lymphoma (7.7%), plasmacytic neoplasm (5.0%), and peripheral T-cell lymphoma, not otherwise specified (3.9%). For most lymphoid neoplasm subtypes, male subjects showed higher rates than female subjects. In summary, our study showed that the epidemiologic features of lymphoid neoplasms in China are distinct from those in Western countries and similar in many ways to those in other countries of the Far East.