Effects of SASH1 on lung cancer cell proliferation, apoptosis, and invasion in vitro

Abstract

The purposes of this study were to investigate the effects of the SASH1 gene on the growth, proliferation, apoptosis, invasiveness, and metastatic potential of lung cancer cells and explore the potential use of SASH1 for the treatment of human lung cancer. The SASH1 gene was cloned into the pcDNA3.1 eukaryotic expression vector, and SASH1 shRNA were designed and constructed. The resulting constructs were transfected into A549 human lung cancer cells, and the changes in the relevant biological characteristics of the cells overexpressing SASH1 and cells with downregulated expression of SASH1 were analyzed using the MTT assay, transwell invasion assay, and flow cytometry. The effects of the SASH1 gene on the expression of cyclin D1, Bcl-2, and MMP-2/9 were also concurrently examined. In the A549 cells from the pcDNA3.1-SASH1 transfected group, cell viability, proliferation, and migration were significantly reduced compared to the control cells (p = 0.039, p = 0.013), and a cell cycle arrest in G1 was observed. The A549 cells transfected with the SASH1 shRNA demonstrated significantly higher cell viabilities, proliferation, and migration compared to the control cells (p = 0.012, p = 0.045). Additionally, the percentage of A549 cells undergoing apoptosis was significantly higher in the pcDNA3.1-SASH1 transfected cells and significantly lower in the SASH1 shRNA transfected cells compared to the control cells (p = 0.010, p = 0.000). The cyclin D1, Bcl-2, and MMP-9/2 protein expression levels were significantly lower in the pcDNA3.1-SASH1-transfected cells and were significantly higher in the SASH1 shRNA-transfected cells than that in the control cells. The SASH1 gene may inhibit A549 cell growth and proliferation as well as promote cellular apoptosis. The overexpression of the SASH1 gene may also be related to the decreased migration of A549 human lung cancer cells.

Effects of SASH1 on melanoma cell proliferation and apoptosis in vitro

“…Moreover, the SASH1 mRNA expression level is also significantly reduced in primary lung cancer and thyroid cancer, while the size of the decrease correlates with the prognosis and tumor size (13). Chen et al proved that SASH1 inhibits cell proliferation and enhances cell apoptosis in the A549 lung cancer cell line (11). All these data suggest that SASH1 plays a crucial role in tumorigenesis, growth and evolution.…”

“…Additionally, Martini et al demonstrated that SASH1 plays a crucial role in tumor formation by regulating the adhesiveness and migratory behavior of cancer cells (10). Furthermore, Chen et al indicated that in the A549 lung cancer cells of the pcDNA3.1-SASH1 transfected group, cell viability, proliferation and migration were significantly reduced compared to the control cells, while a cell cycle arrest was observed in G1 (11). However, the specific mechanism by which SASH1 influences these biological behaviors is yet to be determined.…”

Autosomal-recessive SASH1 variants associated with a new genodermatosis with pigmentation defects, palmoplantar keratoderma and skin carcinoma

“…6,7 Consistent with the onset of carcinoma in the affected individuals in this study, SASH1 was recently reported to be involved in the tumorigenesis of several cancers. [15][16][17][18][19][20] Cellular experiments showed that SASH1 localizes to the nucleus and cytoplasm of epithelial cells and might regulate cellular migration and adhesion, through its role in protruding membrane structures. 21 Through its central SH3 domain, SASH1 interacts with the actin cytoskeleton and especially cortactin, a major regulator of actin filament dynamics.…”

“…SASH1 encodes a candidate tumor suppressor from the SLY family of signal proteins. [15][16][17][18][19][20] This variant was absent from Exome Variant Server, dbSNP and local exomes, predicted as deleterious by Condel and possibly damaging by Polyphen2, and comes from a well-conserved sequence (GERP conservation score: 5090) (see Web Resources). Cosegregation analysis in all available relatives confirmed its presence in a homozygous state in both affected patients (III.6 and III.3), in a heterozygous state in both parents and an unaffected brother (III7) and absent in the unaffected sister (III4).…”

SASH1, a new potential link between smoking and atherosclerosis

“…Recent studies from 2012 focusing on SASH1 function in cancer, 107,108,109,110 showed that SASH1 over-expression in different cancer cell lines lead to accumulation of cells in G0/G1 phase, indicating an inhibitory effect of SASH1 on cell proliferation. Accordingly, cyclin D1 levels were found lowered in all but one cell line and cell invasiveness in vitro assays showed that SASH1 overexpression lead to decreased invasiveness of the cancerous cells.…”