The lysosome-associated SLAMF7 inhibits the development of ovarian cancer by promoting lysosomal damage

Abstract

Ovarian cancer (OC) is one of the most severe cancers worldwide. Recent research suggests that the lysosomal pathway could be applied for early disease screening, prognosis evaluation, and adjuvant therapy. However, whether lysosome-related genes were applied for immune and prognosis prediction in OC remains unclear. RNA sequencing datasets, including clinical information of OC patients, were collected from TCGA and GEO databases. Lysosome-related prognostic genes and functional pathways in OC were identified using the lysosome dataset. The prognostic value of the most significant lysosome-related gene, SLAMF7, was estimated using Kaplan-Meier survival analysis. Differences in genomic mutations, tumor microenvironment immune infiltration, and drug resistance were evaluated in the high/low SLAMF7 of OC patients. The effect of SLAMF7 overexpression on the malignant characteristics of OC was assessed using OC cell lines (HEY A8 and OVCAR3 cells) and a xenograft mouse model. Based on the functional prediction of lysosome-related genes, T cell activation, immune receptor activity, and lysosomal pathways were significantly enriched in OC. Dimensionality reduction analysis using the random survival forest method confirmed that SLAMF7 was the most significantly different lysosome-related prognostic gene in OC. SLAMF7 was downregulated in OC cells and was associated with poor prognosis in OC patients. Low SLAMF7 expression was positively associated with chemotherapy sensitivity, immune infiltration, and function in OC patients. Overexpression of SLAMF7 promoted the pro-CTSB and LAMP1 expression, and inhibited CTSD expression in HEY A8 and OVCAR3 cells. Overexpression of SLAMF7 inhibited proliferation and formation of subcutaneous tumors in nude mice. The lysosome-related gene SLAMF7 is downregulated in OC and could serve as a prognostic biomarker. Overexpression of SLAMF7 inhibited the malignant of OC cells and tumor formation.