10.6084/m9.figshare.1568816.v2 Gloria Yang-Kolodji Gloria Yang-Kolodji Shannon M. Mumenthaler Shannon M. Mumenthaler Arjun Mehta Arjun Mehta Lingyun Ji Lingyun Ji Debu Tripathy Debu Tripathy Phosphorylated ribosomal S6 (p-rpS6) as a post-treatment indicator of HER2 signalling targeted drug resistance Taylor & Francis Group 2015 trastuzumab indicator protein S 6 SKBR 3R Student cell models BT 474R mtt drug resistance Objective HER 2 pathway phosphorylated FACS HER 2 2015-10-08 12:01:38 Dataset https://tandf.figshare.com/articles/dataset/Phosphorylated_ribosomal_S6_p_rpS6_as_a_post_treatment_indicator_of_HER2_signalling_targeted_drug_resistance/1568816 <div><p></p><p><i>Objective</i>: To identify clinically relevant predictive biomarkers of trastuzumab resistance.</p><p><i>Material and methods</i>: MTT, FACS assays, immunoblotting and immunocytochemistry were used to phenotypically characterize drug responses of two cell models BT474R and SKBR3R. Student's <i>t</i>-test and Spearman's correlation were applied for statistic analysis.</p><p><i>Results</i>: The activity of a downstream effector of the HER2 pathway phosphorylated ribosomal protein S6 (p-rpS6), was suppressed by trastuzumab in the parental cell lines yet remained unchanged in the resistant cells following treatment. The level of p-rpS6 was inversely correlated to the drug induced growth inhibition of trastuzumab-resistant cells when they are treated with selected HER2 targeting drugs.</p><p><i>Conclusion</i>: p-rpS6 is a robust post-treatment indicator of HER2 pathway-targeted therapy resistance.</p></div>