Conditioned media derived from mesenchymal stem cells induces apoptosis and decreases cell viability and proliferation in squamous carcinoma cell lines.

Squamous cell carcinoma (SCC) is a relatively common cancer with a low survival rate, poor prognosis and no effective treatment strategy. The use of cell-free conditioned media derived from mesenchymal stem cells (CM-MSCs) has shown promising results in treating various diseases. This study aimed to evaluate the effects of CM-MSCs on proliferation and apoptosis of CAL-27 and FaDu SCC cell lines. CM derived from human bone marrow and human amniotic membrane MSCs (BM-MSCs and AM-MSCs) was used in this investigation. MTT assay demonstrated that CM-BMMSC decreased the viability of CAL-27 and FaDu cell lines, 24, 48, and 72 h after treatment. Quantitative real-time PCR indicated that mRNA expression of PCNA as a proliferative marker, and BCL-2 as an anti-apoptotic protein, decreased in both cell lines treated with CM-BMMSC. Based on the flow cytometry results, the number of positive proliferative Ki67 cells and apoptotic Annexin-V cells decreased and increased in both cell lines treated with CM-BMMSC, respectively. However, CM-AMMSC treatment had both pro-and anti-neoplastic effects in our samples and showed considerable differences between the two cell lines. Taken together, our findings demonstrated that CM-BMMSC and, to a lesser degree, CM-AMMSC decrease cell viability and proliferation and increase cell apoptosis in SCC cell lines in a time-dependent manner. However, further studies are needed, especially to evaluate the anti-tumor potential of CM-BMMSC in vivo.