Anti-CSC effects in human esophageal squamous cell carcinomas and Eca109/9706 cells induced by nanoliposomal quercetin alone or combined with CD 133 antiserum.

CD133 was recently reported to be a cancer stem cell and prognostic marker. Quercetin is considered as a potential chemopreventive agent due to its involvement in suppression of oxidative stress, proliferation and metastasis. In this study, the expression of CD133/CD44 in esophageal carcinomas and Eca109/9706 cells was explored. In immunoflurorescence the locations of CD133+ and multidrug resistance 1 (MDR 1)+ in the same E-cancer cells were coincident, mainly in cytomembranes. In esophageal squamous cell carcinomas detected by double/single immunocytochemistry, small CD133+ cells were located in the basal layer of stratified squamous epithelium, determined as CSLC (cancer stem like cells); CD44+ surrounding the cells appeared in diffuse pattern, and the larger CD44+ (hi) cells were mainly located in the prickle cell layer of the epithelium, as progenitor cells. In E-cancer cells exposed to nanoliposomal quercetin (nLQ with cytomembrane permeability), down-regulation of NF-κBp65, histone deacetylase 1 (HDAC1) and cyclin D1 and up-regulation of caspase-3 were shown by immunoblotting, and attenuated HDAC1 with nuclear translocation and promoted E-cadherin expression were demonstrated by immunocytochemistry. In particular, enhanced E-cadherin expression reflected the reversed epithelial mesenchymal transition (EMT) capacity of nLQ, acting as cancer attenuator/preventive agent. nLQ acting as an HDAC inhibitor induced apoptotic cells detected by TUNEL assay mediated via HDAC-NF-κB signaling. Apoptotic effects of liposomal quercetin (LQ, with cytomembrane-philia) combined with CD133 antiserum were also detected by CD133 immunocytochemistry combined with TUNEL assay. The combination could induce greater apoptotic effects than nLQ induced alone, suggesting a novel anti-CSC treatment strategy.