Prognostic value of ribonucleotide reductase subunit M1 (RRM1) in non-small cell lung cancer: A meta-analysis.

BACKGROUND: Ribonucleotide reductase subunit 1 (RRM1) is a potential prognostic factor for non-small cell lung cancer (NSCLC). This study evaluates prognostic value of RRM1 in NSCLC patients by meta-analyzing outcomes reported in literature. METHOD: Data were acquired from research articles retrieved after literature search in online databases. Random effects meta-analyses were conducted by pooling hazard ratios (HR). Meta-analyses of standardized mean differences (SMD) were used to evaluate overall survival (OS) and progression-free survival (PFS) between low and high RRM1 expression groups. Metaregression analyses were conducted to evaluate the factors that could affect prognostic relationship of RRM1 with treatment and survival outcomes. RESULTS: 23 studies (3148 patients) were included. RRM1 expression was not meaningfully associated with prognosis of NSCLC even when the reference (HR = 1) was either low RRM1 expression (0.918 [95% CI 0.833, 1.003]) or high RRM1 expression (0.834 [0.625, 1.043]). OS was significantly longer in low RRM1 expression group compared to high RRM1 expression group (SMD 0.73 [0.36, 1.09]; P < 0.0001). PFS was not significantly different between low and high RRM1 expression groups (SMD 0.08 [-0.29, 0.45]; p = 0.68). Age was inversely associated with HR (p = 0.001) even when reference was low RRMI (p = 0.027) or high RRM1 (p = 0.006). Age was positively associated with OS in both low and high RRM1 groups. CONCLUSION: In meta-analysis of studies which used gemcitabine-based therapies, higher RRM1 expression is found to associated with shorter OS but not PFS. HR depicting relationship between RRM1 expression and OS/PFS/treatment response could not demonstrate a prognostic role of RRM1 in NSCLC patients.

[Effect of actovegin on intestinal mucosa and expression of bcl-2/bax genes in rats with acute radiation enteritis].

OBJECTIVE: To evaluate the effect of actovegin (Nycomed, deproteinized hemoderivative of calf blood injection) on intestinal mucosa in rats with acute radiation enteritis, and observe the changes of expression of apoptosis-related bcl-2/bax genes. METHODS: An abdominal irradiation in a dose of 9.0 Gy X-ray of linear accelerator was performed once on a group of Wistar rats to establish a model of acute intestinal radiation enteritis. The experimental rats were randomly divided into five groups. Group 1 was normal control group; group 2 was model control group; groups 3, 4 and 5 were treated with low, middle and high dose of actovegin, respectively. After the model was established, actovegin injection was given intraperitoneally for successive 4 days. Corresponding intestinal tissues were taken for morphological examination with an image analysis system. The expression of apoptosis related bax and bcl-2 protein in the intestinal mucosal epithelial cells was determined by immunohistochemistry. RESULTS: The groups 4 and 5 had significantly higher height of intestinal villi, the depth of crypt, the thickness of the mucosa and entire wall (254.66/261.71 microm, 166.47/165.41 microm, 510.44/511.71 microm, 610.38/608.98 microm), compared with those of the model control group (239.12 microm, 151.45 microm, 420.27 microm and 579.32 microm), respectively (P < 0.05). Treatment with middle and high doses of actovegin also significantly down-regulated the expression of activating apoptosis protein bax (24.54/23.24) compared with that of model control group (59.32) (P < 0.05) and up-regulated the expression of inhibiting apoptosis protein bcl-2 (55.54/52.21) compared with that of model control group (20.32) (P < 0.05). The ratio of bcl-2/bax was significantly higher in the groups 4 and 5 (2.2632, 2.1275) compared with that in the model control group (0.3425) (P < 0.01). CONCLUSION: Actovegin accelerates the recovery of the acute radiation-injured intestinal mucosal epithelium by decreasing apoptosis via down-regulation of the expression of activating apoptosis protein bax and up-regulation of inhibiting apoptosis protein bcl-2.