Semaphorin 5A suppresses the proliferation and migration of lung adenocarcinoma cells

Abstract

Semaphorin 5A (SEMA5A), a member of the semaphorin family, plays an important role in axonal guidance. Previously, the authors identified another possible role of SEMA5A as a prognostic biomarker for non-smoking women with lung adenocarcinoma in Taiwan, and this phenomenon has been validated in other ethnic groups. However, the functional significance of SEMA5A in lung adenocarcinoma remains unclear. Therefore, we assessed the function of SEMA5A in three lung adenocarcinoma cell lines in this study. Kaplan-Meier Plotter for lung cancer was conducted for survival analyses. Reverse transcription-quantitative PCR (RT-qPCR) and western blot analysis were performed to investigate the expression and post-translational regulation of SEMA5A in lung adenocar-cinoma cell lines. A pre-designed PyroMark CpG assay and 5-aza-2′-deoxycytidine treatment were used to measure the methylation levels of SEMA5A. The biological functions of lung adenocarcinoma cells overexpressing SEMA5A were investigated by microarrays, and validated both in vitro (proliferation, colony formation and migration assays) and in vivo (tumor xenografts) experiments. The results revealed that the hypermethylation of SEMA5A and the cleavage of the extracellular domain of SEMA5A were responsible for the downregulation of the SEMA5A levels in lung adenocarcinoma cells (A549 and H1299) as compared to the normal controls. Functional analysis of SEMA5A-regulated genes revealed that they were involved in cellular growth and proliferation. The overexpression of SEMA5A in A549 and H1299 cells significantly decreased the proliferation (P<0.01), colony formation (P<0.001) and migratory ability (P<0.01) of the cells. The suppressive effects of SEMA5A on the proliferative and migratory ability of the cells were also observed in both in vitro and in vivo experiments using brain metastatic Bm7 lung adenocarcinoma cells. On the whole, the findings of this study suggest a suppressive role for SEMA5A in lung adenocarcinoma involving the inhibition of the proliferation and migration of lung transformed cells.

A single N6-methyladenosine site in lncRNA HOTAIR regulates its function in breast cancer cells

“…This included genes such as PTK7 involved in the Wnt signaling pathway (fold change relative to control in WT HOTAIR=2.6, p=0.008; in A783U HOTAIR=-1.4, p=0.002); CDH11, a mesenchymal cadherin that is upregulated in invasive breast cancer cell lines (Pishvaian et al, 1999) (fold change in WT HOTAIR=2.0, p=0.01; in A783U HOTAIR=-1.6, p=0.02); and GRIN2A, an oncogenic glutamate receptor (fold change in WT HOTAIR=2.5, p=0.006; in A783U HOTAIR=-3.7, p=9.3E-05). Similarly, genes downregulated with WT HOTAIR were significantly increased with A783U HOTAIR, compared to the parental MDA-MB-231 control, including SEMA5A, a guidance cue protein that suppresses the proliferation and migration of lung adenocarcinoma cells (Ko et al, 2020) (fold change relative to control in WT HOTAIR=-3.5, p=0.0002; in A783U HOTAIR=2.8, p=0.01); SIRPA, a cell surface receptor that can act as a negative regulator of the phosphatidylinositol 3-kinase signaling and mitogenactivated protein kinase pathways (Takahashi, 2018) (fold change in WT HOTAIR=-1.6, p=0.03; in A783U HOTAIR=3.1, p=0.009); and TP53I11, a p53-interacting protein that suppresses migration and metastasis in MDA-MB-231 cells (Xiao et al, 2019) (fold change in WT HOTAIR=-1.7, p=0.03; in A783U HOTAIR=4.0, p=0.008) (Figure 2C). To further analyze differences in cells expressing A783U mutant HOTAIR, we performed a pairwise comparison with control MDA-MB-231 cells and identified 758 differentially expressed genes (Figure 2D).…”

Semaphorins as emerging clinical biomarkers and therapeutic targets in cancer

“…In vitro and in vivo experiments with NSCLC cellular models indicated a clear tumor suppressor activity of Sema5A. These findings suggested a suppressor role for Sema5A in lung adenocarcinomas and a potential relevance as prognostic biomarker 84 .…”

“…Sema5A downregulation in lung adenocarcinoma tissues was associated with poor overall survival. Furthermore, since transmembrane Sema5A can be cleaved by ADAM17 metalloproteases, this mechanism contributes to the downregulation of surface‑exposed Sema5A in lung adenocarcinoma cells 84 . In vitro and in vivo experiments with NSCLC cellular models indicated a clear tumor suppressor activity of Sema5A.…”

Semaphorin 6C Suppresses Proliferation of Pancreatic Cancer Cells via Inhibition of the AKT/GSK3/β-Catenin/Cyclin D1 Pathway

“…However, the secreted form of SEMA5A suppressed the proliferation of pancreatic cancer cells [ 28 ] while also displaying tumor-promoting activities in gastric cancer [ 29 ]. Conversely, this SEMA was suggested to act as a tumor suppressor in lung cancer [ 30 ]. Among the members of the SEMA6 family, SEMA6B and SEMA6D have been implicated in cancer formation.…”