Fig. 1
Characterization of palbociclib-resistant cells with high PEG10 expression and EMT process activation. A Venn diagram representing the number of upregulated genes in MCF7-PR and T47D-PR cells. A gene showing fold change ≥ 2 compared with that in parental cells (MCF7 and T47D) is considered an upregulated gene. B Heat map showing the list of commonly upregulated genes in MCF7-PR and T47D-PR cells. C mRNA expression of PEG10 in the palbociclib-resistant (MCF7-PR and T47D-PR) compared with their corresponding parental (MCF7 and T47D) cells by qRT-PCR. Three independently repeated experiments were performed with similar results. Independent sample t-test: *p < 0.05, **p < 0.01. D Immunoblots showing PEG10 (RF1) and PEG10 (FR2) protein expression in the palbociclib-resistant (MCF7-PR and T47D-PR) and parental (MCF7 and T47D) cells. E Association of PEG10 expression and palbociclib sensitivity using GDSC database. Palbociclib sensitivity was defined as IC50 ≤ 3.5 µM. P-value was calculated by independent sample t-test. F A panel of genes associated with EMT process from microarray data analysis in palbociclib-resistant (MCF7-PR and T47D-PR) versus parental (MCF7 and T47D) cells. G mRNA expression of EMT markers in the palbociclib-resistant (MCF7-PR and T47D-PR) cells compared with their corresponding parental (MCF7 and T47D) cells by qRT-PCR. Three independently repeated experiments were performed with similar results. Independent sample t-test: *p < 0.05, **p < 0.01, ***p < 0.001, Abbreviation: ns, not significant. H Immunoblots showing protein expression of mesenchymal markers (ZEB1 & LAMC2), and epithelial marker (E-cadherin) in MCF7-PR and T47D-PR cells compared with MCF7 and T47D cells, respectively. I Association of ZEB1 expression and palbociclib sensitivity in 11 HR+ breast cancer cell lines from GDSC database. Palbociclib sensitivity was defined as IC50 ≤ 3.5 µM. P-value was calculated by independent sample t-test