PKC-mediated phosphorylation and activation of the MEK/ERK pathway as a mechanism of acquired trastuzumab resistance in HER2-positive breast cancer
Protein expression, activation and stability are regulated through inter-connected signal transduction pathways resulting in specific cellular states. This study sought to differentiate between the complex mechanisms of intrinsic and acquired trastuzumab resistance, by quantifying changes in express...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2022-10-01
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| Series: | Frontiers in Endocrinology |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fendo.2022.1010092/full |
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| author | Jeanesse Scerri Christian Scerri Felix Schäfer-Ruoff Simon Fink Markus Templin Godfrey Grech |
| author_facet | Jeanesse Scerri Christian Scerri Felix Schäfer-Ruoff Simon Fink Markus Templin Godfrey Grech |
| author_sort | Jeanesse Scerri |
| collection | DOAJ |
| description | Protein expression, activation and stability are regulated through inter-connected signal transduction pathways resulting in specific cellular states. This study sought to differentiate between the complex mechanisms of intrinsic and acquired trastuzumab resistance, by quantifying changes in expression and activity of proteins (phospho-protein profile) in key signal transduction pathways, in breast cancer cellular models of trastuzumab resistance. To this effect, we utilized a multiplex, bead-based protein assay, DigiWest®, to measure around 100 proteins and protein modifications using specific antibodies. The main advantage of this methodology is the quantification of multiple analytes in one sample, utilising input volumes of a normal western blot. The intrinsically trastuzumab-resistant cell line JIMT-1 showed the largest number of concurrent resistance mechanisms, including PI3K/Akt and RAS/RAF/MEK/ERK activation, β catenin stabilization by inhibitory phosphorylation of GSK3β, cell cycle progression by Rb suppression, and CREB-mediated cell survival. MAPK (ERK) pathway activation was common to both intrinsic and acquired resistance cellular models. The overexpression of upstream RAS/RAF, however, was confined to JIMT 1; meanwhile, in a cellular model of acquired trastuzumab resistance generated in this study (T15), entry into the ERK pathway seemed to be mostly mediated by PKCα activation. This is a novel observation and merits further investigation that can lead to new therapeutic combinations in HER2-positive breast cancer with acquired therapeutic resistance. |
| first_indexed | 2024-04-12T12:29:53Z |
| format | Article |
| id | doaj.art-88bc182dd81e471287768db22eecb0fc |
| institution | Directory Open Access Journal |
| issn | 1664-2392 |
| language | English |
| last_indexed | 2024-04-12T12:29:53Z |
| publishDate | 2022-10-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Endocrinology |
| spelling | doaj.art-88bc182dd81e471287768db22eecb0fc2022-12-22T03:33:03ZengFrontiers Media S.A.Frontiers in Endocrinology1664-23922022-10-011310.3389/fendo.2022.10100921010092PKC-mediated phosphorylation and activation of the MEK/ERK pathway as a mechanism of acquired trastuzumab resistance in HER2-positive breast cancerJeanesse Scerri0Christian Scerri1Felix Schäfer-Ruoff2Simon Fink3Markus Templin4Godfrey Grech5Department of Physiology & Biochemistry, University of Malta, Msida, MaltaDepartment of Physiology & Biochemistry, University of Malta, Msida, MaltaNMI Natural and Medical Sciences Institute, University of Tübingen, Reutlingen, GermanyNMI Natural and Medical Sciences Institute, University of Tübingen, Reutlingen, GermanyNMI Natural and Medical Sciences Institute, University of Tübingen, Reutlingen, GermanyDepartment of Pathology, University of Malta, Msida, MaltaProtein expression, activation and stability are regulated through inter-connected signal transduction pathways resulting in specific cellular states. This study sought to differentiate between the complex mechanisms of intrinsic and acquired trastuzumab resistance, by quantifying changes in expression and activity of proteins (phospho-protein profile) in key signal transduction pathways, in breast cancer cellular models of trastuzumab resistance. To this effect, we utilized a multiplex, bead-based protein assay, DigiWest®, to measure around 100 proteins and protein modifications using specific antibodies. The main advantage of this methodology is the quantification of multiple analytes in one sample, utilising input volumes of a normal western blot. The intrinsically trastuzumab-resistant cell line JIMT-1 showed the largest number of concurrent resistance mechanisms, including PI3K/Akt and RAS/RAF/MEK/ERK activation, β catenin stabilization by inhibitory phosphorylation of GSK3β, cell cycle progression by Rb suppression, and CREB-mediated cell survival. MAPK (ERK) pathway activation was common to both intrinsic and acquired resistance cellular models. The overexpression of upstream RAS/RAF, however, was confined to JIMT 1; meanwhile, in a cellular model of acquired trastuzumab resistance generated in this study (T15), entry into the ERK pathway seemed to be mostly mediated by PKCα activation. This is a novel observation and merits further investigation that can lead to new therapeutic combinations in HER2-positive breast cancer with acquired therapeutic resistance.https://www.frontiersin.org/articles/10.3389/fendo.2022.1010092/fullacquired resistancebreast cancerphospho-profilePKC/MEK/ERKsignalosomeHER2 positive |
| spellingShingle | Jeanesse Scerri Christian Scerri Felix Schäfer-Ruoff Simon Fink Markus Templin Godfrey Grech PKC-mediated phosphorylation and activation of the MEK/ERK pathway as a mechanism of acquired trastuzumab resistance in HER2-positive breast cancer Frontiers in Endocrinology acquired resistance breast cancer phospho-profile PKC/MEK/ERK signalosome HER2 positive |
| title | PKC-mediated phosphorylation and activation of the MEK/ERK pathway as a mechanism of acquired trastuzumab resistance in HER2-positive breast cancer |
| title_full | PKC-mediated phosphorylation and activation of the MEK/ERK pathway as a mechanism of acquired trastuzumab resistance in HER2-positive breast cancer |
| title_fullStr | PKC-mediated phosphorylation and activation of the MEK/ERK pathway as a mechanism of acquired trastuzumab resistance in HER2-positive breast cancer |
| title_full_unstemmed | PKC-mediated phosphorylation and activation of the MEK/ERK pathway as a mechanism of acquired trastuzumab resistance in HER2-positive breast cancer |
| title_short | PKC-mediated phosphorylation and activation of the MEK/ERK pathway as a mechanism of acquired trastuzumab resistance in HER2-positive breast cancer |
| title_sort | pkc mediated phosphorylation and activation of the mek erk pathway as a mechanism of acquired trastuzumab resistance in her2 positive breast cancer |
| topic | acquired resistance breast cancer phospho-profile PKC/MEK/ERK signalosome HER2 positive |
| url | https://www.frontiersin.org/articles/10.3389/fendo.2022.1010092/full |
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