Background: Rab27A and Rab27B are the major components of vesicle fusion and trafficking in exosome secretion and play important roles in tumor progression and metastasis. In addition, Rab27A and Rab27B are associated with tumor prognosis. This study investigated the prognostic roles of Rab27A and Rab27B expression in patients with non‐small cell lung cancer (NSCLC).Methods: Rab27A and Rab27B expression was assessed in 133 cases of NSCLC by immunohistochemistry. We evaluated the correlations between Rab27A and Rab27B expression and clinicopathological data and determined their prognostic role in NSCLC.Results: Rab27A and Rab27B expression were significantly related to patient gender (P = 0.007 and 0.002, respectively) and histologic type (P = 0.009 and < 0.001, respectively), but not to patient age, smoking history, surgical method, or tumor node metastasis stage. The multivariate Cox proportional hazards regression model verified that high Rab27B expression is a prognostic factor for unfavorable disease‐specific survival (hazard ratio 2.680, 95% confidence interval 1.116–6.437; P = 0.027) in squamous cell carcinoma (SQCC). Kaplan–Meier analysis revealed significantly poorer prognosis in SQCC patients with high Rab27B expression compared to patients with low Rab27B expression (P = 0.030).Conclusion: High Rab27B expression could be an unfavorable prognostic factor in patients with SQCC of the lung.

The immunotherapeutic role of programmed death-ligand 1 (PD-L1) in life expectancy in many cancers has been highlighted. However, data regarding PD-L1 expression in papillary thyroid carcinoma (PTC) are limited. In this study, we describe the PD-L1 and programmed cell death protein 1 (PD-1) expressions in PTC and analyze their correlation with lymph node (LN) metastasis. Clinicopathological data were obtained from 116 patients with PTC who were treated in Gyeongsang National University Hospital, Jinju, Korea in 2009. Tissue microarray blocks were made using representative paraffin blocks of classical PTCs excluding follicular variants. Two pathologists graded the proportion and intensity of PD-L1 and PD-1 expression in both tumor and inflammatory cells. According to their proportions, positive PTC cells were scored as negative (0%), grade 1 (1%-50%), and grade 2 (51%-100%). Similarly, positive inflammatory cells were graded as negative (0%), grade 1 (1%-10%), and grade 2 (11%-20%). The intensity of each protein expression was simplified as positive or negative. A statistically significant correlation exists between the proportions of PD-1 and PD-L1 expression both in papillary carcinoma (p=.001) and peritumoral lymphoid cells in the thyroid (p<.001). In addition, the proportion of PD-L1 expression in PTC cells was closely related to metastatic LNs (p=.036). PD-L1 is a valuable predictive marker for LN metastasis in PTC. Immunomodulating therapies that inhibit PD-L1 might be an option for patients with LN metastasis.

S100A8 and S100A9 have been gaining recognition for modulating tumor growthand metastasis. This study aimed at evaluating the clinical significance of S100A8 and S100A9 innon-small cell lung cancer (NSCLC). We analyzed the relationship between S100A8and S100A9 expressions, clinicopathological characteristics, and prognostic significance in tumorcells and peritumoral inflammatory cells. The positive staining of S100A8 in tumorcells was significantly increased in male (p < .001), smoker (p = .034), surgical method other thanlobectomy (p = .024), squamous cell carcinoma (SQCC) (p < .001) and higher TNM stage (p = .022)compared with female, non-smoker, lobectomy, adenocarcinoma (ADC), and lower stage. Theproportion of tumor cells stained for S100A8 was related to histologic type (p < .001) and patientsex (p = .027). The proportion of inflammatory cells stained for S100A8 was correlated with patientage (p = .022), whereas the proportion of inflammatory cells stained for S100A9 was correlatedwith patient sex (p < .001) and smoking history (p = .031). Moreover, positive staining in tumorcells, more than 50% of the tumor cells stained and less than 30% of the inflammatory cellsstained for S100A8 and S100A9 suggested a tendency towards increased survivability in SQCCbut towards decreased survivability in ADC. S100A8 and S100A9 expressions might be potential prognostic markers in patients with NSCLC.

Background/Aim: RAB27A and RAB27B are involved in exosome secretion. To date, there have been many attempts to elucidate the roles of RAB27A and RAB27B in the prognosis of various cancer types. The association of RAB27A and RAB27B expression with the clinical and pathological features was evaluated in patients with stomach cancer. Materials and Methods: A total of 360 patients who had undergone surgery for stomach cancer between January 1999 and December 2007 at Gyeongsang National University were enrolled in the study. Disease-free survival (DFS) and disease-specific survival (DSS) were compared according to immunohistochemistry of tumor samples. RAB27A and RAB27B mRNA and protein were also extracted from four stomach cancer cell lines using quantitative polymerase chain reaction and western blotting. Results: Strong nuclear RAB27A expression in tumor samples was statistically significantly correlated with lymph node metastasis. Cytoplasmic RAB27B expression was related to poor disease-free survival and its combined cytoplasmic and membranous expression was related to disease-specific survival of patients with different histopathological types of stomach cancer. High RAB27A expression and high RAB27B expression was found in four stomach cancer cell blocks. Among the four cell lines, NCI-N87 exhibited the lowest relative mRNA density and HS746T exhibited the highest relative protein density for both RAB27A and RAB27B. Conclusion: RAB27A and RAB27B expression may help predict lymph node metastasis and survival of patients with gastric cancer.