Clinicopathologic Significance and Prognostic Value of Programmed Cell Death Ligand 1 (PD-L1) in Patients With Hepatocellular Carcinoma: A Meta-Analysis.

Background: There is still a dispute over an issue of the clinical pathology and prognostic of programmed cell death ligand 1 (PD-L1) in hepatocellular carcinoma (HCC) patients. Here, we undertook this meta-analysis to survey the conceivable role of PD-L1 in HCC. Method: We searched databases like MEDLINE, EMBASE, and Google Scholar for relevant studies published in English up to February 13, 2018. We implemented the appraisal of the eligible studies according to the choice criterion. We used Hazard ratio (HR) and its 95% confidence interval (95% CI) to evaluate the prognostic role of PD-L1 for overall survival (OS), disease-free survival (DFS), and recurrence-free survival (RFS). Odds ratio (OR) and the corresponding 95% CI were calculated to evaluate the connection between PD-L1 and clinicopathological features. Publication bias was tested. Results: 13 studies, which published range from 2009 to 2017 were contained in this meta-analysis, involving 1,843 patients with HCC. The results indicated that high PD-L1 could predict shorter OS (HR = 1.57, 95% CI: 1.09-2.27, P < 0.00001) as well as poorer DFS (HR = 2.07, 95% CI: 1.20-3.58, P = 0.009). Additionally, high PD-L1 expression was correlated to liver cirrhosis (OR = 1.66, 95% CI: 1.10-2.50, P = 0.02), poorer tumor Barcelona Clinical Liver Cancer (BCLC) stage (OR = 0.30, 95% CI: 0.10-0.88, P = 0.03) and portal vein invasion (OR = 1.96, 95% CI: 1.04-3.68, P = 0.04), but had no correlation with age, gender, tumor size, number of tumors, AFP, vascular invasion, HBVs-Ag, Anti-HCV, differentiation or TNM stage. Besides, no significant publication bias was found among these identified studies. Conclusion: The meta-analysis suggested that PD-L1 overexpression could foresee worse OS and DFS in HCC. Moreover, the PD-L1 expression has to bear on liver cirrhosis, portal vein invasion, and BCLC stage.

Reduced expression of Slit2 in renal cell carcinoma.

Slit2, initially identified as an important axon guidance molecule in the nervous system, was suggested to be involved in multiple cellular processes. Recently, Slit2 was reported to function as a potential tumor suppressor in diverse tumors. In this study, we systematically analyzed the expression level of Slit2 in renal cell carcinoma. Compared to paired adjacent non-malignant tissues, both Slit2 mRNA and protein expression were significantly down-regulated in renal cell carcinoma (RCC). Methylation-specific PCR showed that Slit2 promoter was methylated in two renal carcinoma cell lines. Pharmacologic demethylation dramatically induced Slit2 expression in cancer cell lines with weak expression of Slit2. Besides, bisulfite genomic sequencing confirmed that dense methylation existed in Slit2 promoter. Furthermore, in paired RCC samples, Slit2 methylation was observed in 8 out of 38 patients (21.1 %), which was well correlated with the down-regulation of Slit2 in RCC. Therefore, Slit2 may also be a potential tumor suppressor in RCC, which is down-regulated in RCC partially due to promoter methylation.

Proteomic profiles of soluble proteins from the esophageal gland in female Meloidogyne incognita.

Meloidogyne incognita can infect multiple plant species. Proteins synthesized in the esophageal glands and secreted through the stylet of plant parasitic nematodes play critical roles in the plant-nematode interactions. Female M. incognita live for approximately 15days, embedded in a host plant, but their esophageal gland proteins have not yet been comprehensively analyzed. In this study, a new bacterium-contamination-resistant method for collecting soluble proteins from esophageal gland cells (SPEGC) of female M. incognita was established. Approximately 5µg of freeze-dried proteins could be extracted from 150 female M. incognita. Bands of a one-dimensional SDS-polyacrylamide gel were excised after electrophoresis of 20µg of protein and were analyzed. Two hundred and forty-six proteins from SPEGC of female M. incognita were identified by LC-MS/MS. Gene Ontology analysis suggests that many of the secreted proteins are involved in protein or carbohydrate metabolism and proteolysis. Some of the SPEGC (46.3%) were predicted to be secreted through classical or non-classical secretory pathways. The described method presents a new approach for the identification of proteins stored in SPEGC of an important plant parasitic nematode. This global proteomic profile of SPEGC provides a basis for future studies to elucidate the functions of proteins secreted from female M. incognita on plant responses.