Pathological significance of abnormal recepteur d'origine nantais and programmed death ligand 1 expression in colorectal cancer

BACKGROUND Programmed death ligand 1(PD-L1) immunotherapy remains poorly efficacious in colorectal cancer(CRC). The recepteur d'origine nantais(RON) receptor tyrosine kinase plays an important role in regulating tumor immunity.AIM To identify the patterns of RON and PD-L1 expression and explore their clinical significance in CRC.METHODS Gene expression data from the Gene Expression Omnibus database(GEO;n = 290) and patients at the First Affiliated Hospital, Zhejiang University School of Medicine(FAHZUSM;n = 381) were analyzed to determine the prognostic value of RON and PD-L1 expression within the tumor microenvironment of CRC. HT29 cell line was treated with BMS-777607 to explore the relationship between RON activity and PD-L1 expression. Signaling pathways and protein expression perturbed by RON inhibition were evaluated by cellular immunofluorescence and Western blot.RESULTS In the GEO patient cohort, cut-off values for RON and PD-L1 expression were determined to be 7.70 and 4.3, respectively. Stratification of patients based on these cutoffs demonstrated that high expression of RON and PD-L1 was associated with a poor prognosis. In the FAHZUSM cohort, rates of high expression of RON in tumor cells, high PD-L1 expression in tumor cells and tumor infiltrating monocytes, and both high RON and high PD-L1 expression in the tumor microenvironment were 121(32%), 43(11%), 91(24%), and 51(13.4%), respectively. High expression of RON was significantly correlated with high expression of PD-L1 in the tumor cell compartment(P < 0.001). High expression of RON and that of PD-L1 were independent prognostic factors for poorer overall survival. Concurrent high expression of both RON and PD-L1 in the tumor microenvironment was significantly associated with a poor prognosis. In vitro, BMS-777607 inhibited the phosphorylation of RON, inhibited PD-L1 expression, and attenuated activation of the ERK1/2 and AKT signaling pathways in CRC cells.CONCLUSION RON, PD-L1, and their crosstalk are significant in predicting the prognostic value of CRC. Moreover, phosphorylation of RON upregulates PD-L1 expression, which provides a novel approach to immunotherapy in CRC.

Strive for the Modern Town with the Specialized Production of Boxes and Bags——Sidelights on Nantai Town Economy

Nantai town is located at the south of Liaoning Province, North is Anshan, Haichengis on the south, Shenda expressway, Hada highway and railway crisscross the town fromnorth to south. Nantai town covers an areas of 95 square Kgs with 23 administrativevillages, 4 sub-district offices, 1 economic development zone and there are 15 thousandfamilies and 54 thousand populations. Nantai town is a trial place for overall structuralreform in Liaoning Province and a center on larger-scale production, processing anddistributing of boxes and bags nationwide.