Biomedicines
miR-221/222 Profiles in Small Extracellular Vesicles Derived from Gemcitabine-Sensitive and -Resistant A549 Cancer Stem-like Cell Spheroids: An In Vitro Study
By Ghorbani A, Uysal O and Karacaoğlu D.
Abstract
Background
Gemcitabine is used in the treatment of human non-small cell lung cancer (hNSCLC), yet acquired resistance can limit therapeutic responses. Small extracellular vesicles (sEVs) and microRNAs (miRNAs) have been implicated in chemoresistance-associated intercellular signaling. We profiled the miR-221/222 cluster and resistance-associated genes in cancer stem-like cells (CSLCs) and CSLC-derived sEV preparations from gemcitabine-sensitive and -resistant A549 models.
Methods
Gemcitabine-resistant A549 cells and matched cancer stem-like cell (CSLC) and gemcitabine-resistant cancer stem-like cell (Gr-CSLC) populations were generated and characterized by flow cytometry, qRT-PCR, and immunofluorescence. sEV preparations derived from CSLC and Gr-CSLC spheroids were characterized for total protein content, EV-associated tetraspanins, and vesicular morphology. PKH26-associated fluorescence following exposure of A549 cells to labeled sEV preparations was also evaluated. The relative levels of sEV-associated miR-221/222 family members and the resistance-associated genes MDR1, ABCG2, and BCL2 were assessed by qRT-PCR.