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

ABSTRACT: OBJECTIVE:To identify clinically relevant predictive biomarkers of trastuzumab resistance. MATERIAL AND METHODS:MTT, FACS assays, immunoblotting and immunocytochemistry were used to phenotypically characterize drug responses of two cell models BT474R and SKBR3R. Student's t-test and Spearman's correlation were applied for statistic analysis. RESULTS: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. CONCLUSION:p-rpS6 is a robust post-treatment indicator of HER2 pathway-targeted therapy resistance.

SUBMITTER: Yang-Kolodji G

PROVIDER: S-EPMC7447531 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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

Yang-Kolodji Gloria G Mumenthaler Shannon M SM Mehta Arjun A Ji Lingyun L Tripathy Debu D

Biomarkers : biochemical indicators of exposure, response, and susceptibility to chemicals 20150101 5

<h4>Objective</h4>To identify clinically relevant predictive biomarkers of trastuzumab resistance.<h4>Material and methods</h4>MTT, FACS assays, immunoblotting and immunocytochemistry were used to phenotypically characterize drug responses of two cell models BT474R and SKBR3R. Student's t-test and Spearman's correlation were applied for statistic analysis.<h4>Results</h4>The activity of a downstream effector of the HER2 pathway phosphorylated ribosomal protein S6 (p-rpS6), was suppressed by tras ...[more]

PMID: 26329528

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