Elevated miR-21 is associated with poor prognosis in non-small cell lung cancer: a systematic review and meta-analysis.

OBJECTIVE: Increasing studies have investigated the prognostic value of high miR-21 expression in non-small cell lung cancer (NSCLC) with inconsistent results. We conducted this meta-analysis to explore whether the expression of miR-21 was associated with prognosis in NSCLC patients. MATERIALS AND METHODS: We systematically searched Medline, EMBASE, Web of Science and Cochrane Library for relevant studies. Studies exploring the relationship between miR-21 expression and NSCLC prognosis and clinical pathology, and reporting enough data to get the hazard ratio (HR) and 95% confidence intervals (CIs), were included. Random- or fixed-effect models were employed to calculated pooled hazard ratios (HRs) or risk ratio and 95% confidence intervals (95% CIs). RESULTS: A total of 28 eligible studies, including 24 for prognosis, 16 for clinicopathological features were identified. Our results revealed that elevated miR-21 was related to unfavorable overall survival (OS) in NSCLC (HR = 1.960, 95% CI = 1.510-2.554, p = 0.000). Similar results were found in disease-free survival, relapse-free survival, and cancer-special death. In a meta-analysis of clinical pathology, overexpressed miR-21 was significantly related to lung adenocarcinoma, larger tumor size, and advanced clinical stage. CONCLUSIONS: Our meta-analysis suggested that miR-21 may function as an unfavorable biomarker of prognosis in NSCLC patients.

[Preliminary study for the roles and mechanisms of 20(R)-ginsenoside Rg3 and PEG-PLGA-Rg3 nanoparticles in the Lewis lung cancer mice].

OBJECTIVE: To comparatively observe the effects of 20(R)-ginsenoside Rg3 and PEG-PLGA-Rg3 nanoparticles on the Lewis lung cancer mice and to explore the mechanisms of Rg3 and PEG-PLGA-Rg3 nanoparticle anti-cancer in vivo. METHODS: Lewis lung cancer mouse model was established and 60 mice were randomly divided into 5 groups with twelve in each group: PEG-PLGA-Rg3 nanoparticles group(Rg3-N), PEG-PLGA group (PEG), Rg3 group (Rg3), normal control group(C), saline control group(NS), and received intragastric administration for 14 days. The weights of the mice were measured every 2 days and the weight curves were obtained. At the same time, the color pattern, activity and mental status were observed. The mice were sacrificed when the administration was over, and the effects of 20(R)-ginsenoside Rg3 and PEG-PLGA-Rg3 nanoparticles on tumor weight, and the tumor:weight ratios were analysed. In addition, the tumor microvessel density (MVD) was measured by immunohistochemical staining with anti-CD31 antibody to compare the effects of Rg3 and PEG-PLGA-Rg3 nanoparticles on the tumor angiogenesis in vivo. Furthermore, the levels of such angiogenesis and proliferation factors as MMP-9, HIF-1α, VEGF, Ki-67 were examined by RT-PCR, Western blot and immunohistochemistry to explore the internal molecular mechanisms of anti-tumor effects in vivo. RESULTS: The trends of variation of the mice weights in NS group and PEG group were rising early but declining later. In contrast, the trends of the other three groups were rising early and became stable later. In comparison with NS group, the mice of Rg3 group and Rg3-N group had better general status: brighter color, more active and better spirit. Compared with NS group,the tumor weight in PEG group, Rg3 group and Rg3-N group showed no significant difference but the tumor:weight ratio and MVD in Rg3 group and Rg3-N group declined significantly (P<0.01). Besides, there was no significant difference between Rg3 group and Rg3-N group. At the same time, the level of VEGF mRNA, the protein expression of MMP-9, HIF-1α, VEGF in Rg3 group and Rg3-N group decreased compared with NS group. Furthermore, the level of each index above-mentioned in Rg3-N group was lower than that in Rg3 group. The expression of Ki-67 in PEG group, Rg3 group and Rg3-N group showed no significant difference compared with NS group. CONCLUSION: Rg3 and PEG-PLGA-Rg3 nanoparticle may suppress the expression of VEGF, MMP-9 and HIF-1α in Lewis lung cancer mice, thereby indirectly contributing to their antitumor effects and alleviating the mice's general status. In addition, PEG-PLGA nanoparticles embedding can promote Rg3 antitumor effect in vivo.