Selective Inhibition of Esophageal Cancer Stem like Cells with Salinomycin.

BACKGROUND: Targeting Cancer stem like cells (CSLCs) can provide promising new therapeutic strategies to inhibit both cancer progression, metastasis and recurrence. Salinomycin (Sal), an antibacterial ionophore, has been shown to specifically inhibit CSCs. Recently it has been reported that Sal can destabilize TAZ, the hypo pathway transducer in CSLCs. OBJECTIVE: Here in the current study, we aimed to assess the differential toxicity of Sal in esophageal CSLCs and its relation to TAZ gene expression. METHOD: The esophageal cancer cell line, KYSE-30 was used for enrichment of CSLCs. The expression of TAZ was knocked down using specific siRNA transfection and then the cytotoxicity of Sal was measured using XTT assay. The qRT-PCR method was used for gene expression assessment and the sphere formation ability was monitored using light microscopy. RESULT: Our findings showed esophageal CSLCs over-express stemness-associated genes including SOX2, OCT4 as well as TAZ (~ 14 fold, p value=0.02) transcription coactivator. We found Sal can selectively inhibit KYSE-30 CSLCs viability and sphere formation ability; however, TAZ knockdown does not change its differential toxicity. ConclusionIn: overall, our results indicate Sal can selectively decrease viability of esophageal CSLCs in a TAZ-independent manner.