Journal: Journal of Experimental & Clinical Cancer Research : CR
Article Title: The G Protein Estrogen Receptor (GPER) is involved in the resistance to the CDK4/6 inhibitor palbociclib in breast cancer
doi: 10.1186/s13046-024-03096-7
Figure Lengend Snippet: EGFR or GPER silencing restore palbociclib sensitivity in MCF7/PalbR cells. A Representative pictures of spheroids (a single spheroid/well) from MCF7/PalbR/shRNA and MCF7/PalbR/shEGFR spheroid cultures grown for 6 days on agar-coated plates. B Quantification of spheroid growth; values of MCF7/PalbR/shRNA cells were set as 100% upon which the number of MCF7/PalbR/shEGFR cells was determined. C Efficacy of EGFR silencing in MCF7/PalbR/shEGFR cells. D Representative pictures of spheroids (a single spheroid/well) from the MCF7/PalbR/shRNA and MCF7/PalbR/shGPER spheroid cultures grown for 6 days on agar-coated plates. Scale bar 500 μm. E Quantification of spheroid growth; values of MCF7/PalbR/shRNA cells were set as 100% upon which the number of MCF7/PalbR/shGPER cells was determined. F Efficacy of GPER silencing in MCF7/PalbR/shGPER cells. G Colony formation assay in in MCF7/PalbR/shRNA and MCF7/PalbR/shGPER cells. Plates were stained with Crystal Violet and colonies were counted following 10 days of incubation. ( H ). I Protein levels of cyclin D1, cyclin E1 and GPER in MCF7/PalbR/shRNA and MCF7/PalbR/shGPER cells. Side panels show densitometric analyses of the blots normalized to β-actin, which served as loading control. Values represent the mean ± SD of three independent experiments performed in triplicate. (*) indicates p < 0.05. Kaplan-Meier survival curves representing the overall survival ( J ) and relapse-free survival ( K ) in ER-positive BC patients of the METABRIC database, based on low vs high EGFR and GPER mRNA levels (median values were used as threshold)
Article Snippet: Equal amounts of whole-protein extract were resolved on an 8% or 10% SDS-polyacrylamide gel and transferred to nitrocellulose membranes (Merck, Milan, Italy), which were probed with primary antibodies against ERα (F-10), EGFR (A-10), c-Fos (E-8), EGR1 (S-25), Cyr61 (A-10), p21 (H164), phosphorylated ERK1/2 (E-4), ERK2 (C-14), and β-actin (AC-15) (Santa Cruz Biotechnology, DBA, Milan, Italy), GPER (AB137479; Abcam, DBA, Milan, Italy), pAKT (4060) and AKT (9272) (Cell Signaling, Euroclone, Milan, Italy), cyclin D1 (TA801655) and cyclin E1 (AP06082PU-N) (purchased from OriGene Technologies, DBA, Milan, Italy) , and then revealed using the chemiluminescent substrate for western blotting Clarity™ Western ECL Substrate (Bio-Rad, Milan, Italy).
Techniques: shRNA, Colony Assay, Staining, Incubation, Control
