Phosphorylated ribosomal S6 (p-rpS6) as a post-treatment indicator of HER2 signalling targeted drug resistance. (July 2015)

• Record Type: Journal Article
• Authors: Yang-Kolodji, Gloria; Mumenthaler, Shannon M.; Mehta, Arjun; Ji, Lingyun; Tripathy, Debu
• Is Part Of: Biomarkers. Volume 20:Number 5(2015)
• Page Start: 313
• Page End: 322
• Publication Date: 2015-07
• Subjects: Biochemical markers -- Periodicals; 610.28
• Languages: English
• ISSNs: 1354-750X

Abstract

<abstract> <title>Abstract</title> <p> <italic>Objective</italic>: To identify clinically relevant predictive biomarkers of trastuzumab resistance.</p> <p> <italic>Material and methods</italic>: MTT, FACS assays, immunoblotting and immunocytochemistry were used to phenotypically characterize drug responses of two cell models BT474R and SKBR3R. Student's <italic>t</italic>-test and Spearman's correlation were applied for statistic analysis.</p> <p> <italic>Results</italic>: 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> <italic>Conclusion</italic>: p-rpS6 is a robust post-treatment indicator of HER2 pathway-targeted therapy resistance.</p> </abstract>