Browse
Submit Data
Databases
API
Help

Dataset Information

37 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Feedback upregulation of HER3 (ErbB3) expression and activity attenuates antitumor effect of PI3K inhibitors.

ABSTRACT: We examined the effects of an inhibitor of PI3K, XL147, against human breast cancer cell lines with constitutive PI3K activation. Treatment with XL147 resulted in dose-dependent inhibition of cell growth and levels of pAKT and pS6, signal transducers in the PI3K/AKT/TOR pathway. In HER2-overexpressing cells, inhibition of PI3K was followed by up-regulation of expression and phosphorylation of multiple receptor tyrosine kinases, including HER3. Knockdown of FoxO1 and FoxO3a transcription factors suppressed the induction of HER3, InsR, IGF1R, and FGFR2 mRNAs upon inhibition of PI3K. In HER2(+) cells, knockdown of HER3 with siRNA or cotreatment with the HER2 inhibitors trastuzumab or lapatinib enhanced XL147-induced cell death and inhibition of pAKT and pS6. Trastuzumab and lapatinib each synergized with XL147 for inhibition of pAKT and growth of established BT474 xenografts. These data suggest that PI3K antagonists will inhibit AKT and relieve suppression of receptor tyrosine kinase expression and their activity. Relief of this feedback limits the sustained inhibition of the PI3K/AKT pathway and attenuates the response to these agents. As a result, PI3K pathway inhibitors may have limited clinical activity overall if used as single agents. In patients with HER2-overexpressing breast cancer, PI3K inhibitors should be used in combination with HER2/HER3 antagonists.

SUBMITTER: Chakrabarty A

PROVIDER: S-EPMC3286932 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Relief of feedback inhibition of HER3 transcription by RAF and MEK inhibitors attenuates their antitumor effects in BRAF mutant thyroid carcinomas.

Project description:Analysis of transcriptome kinetics of SW1736 thyroid cancer cell line vs SK-MEL-28 melanoma cell line at various times after addition of 2 µM vemurafenib. The hypothesis tested was that SW1736 cells (vemurafenib-refractory) differentially express genes compared to SK-MEL-28 cells (vemurafenib sensitive) that confer resistance to the RAF inhibitor. Total RNA was obtained from lysates of SW1726 and SK-MEL-28 cells treated with 2 µM vemurafenib for 0, 1, 6 and 48 h. Experiment was made by triplicate.

2013-02-01 | E-GEOD-37441 | biostudies-arrayexpress

Relief of feedback inhibition of HER3 transcription by RAF and MEK inhibitors attenuates their antitumor effects in BRAF-mutant thyroid carcinomas.

Project description:The RAF inhibitor vemurafenib (PLX4032) increases survival in patients with BRAF-mutant metastatic melanoma, but has limited efficacy in patients with colorectal cancers. Thyroid cancer cells are also comparatively refractory to RAF inhibitors. In contrast to melanomas, inhibition of mitogen-activated protein kinase (MAPK) signaling by PLX4032 is transient in thyroid and colorectal cancer cells. The rebound in extracellular signal-regulated kinase (ERK) in thyroid cells is accompanied by increased HER3 signaling caused by induction of ERBB3 (HER3) transcription through decreased promoter occupancy by the transcriptional repressors C-terminal binding protein 1 and 2 and by autocrine secretion of neuregulin-1 (NRG1). The HER kinase inhibitor lapatinib prevents MAPK rebound and sensitizes BRAF-mutant thyroid cancer cells to RAF or MAP-ERK kinase inhibitors. This provides a rationale for combining ERK pathway antagonists with inhibitors of feedback-reactivated HER signaling in this disease. The determinants of primary resistance to MAPK inhibitors vary between cancer types, due to preferential upregulation of specific receptor tyrosine kinases, and the abundance of their respective ligands.

| S-EPMC3651738 | biostudies-literature

Relief of feedback inhibition of HER3 transcription by RAF and MEK inhibitors attenuates their antitumor effects in BRAF mutant thyroid carcinomas

| S-ECPF-GEOD-37441 | biostudies-other

Feedback activation of HER3 attenuates response to EGFR inhibitors in colon cancer cells.

Project description:The EGFR inhibitor cetuximab is approved for the treatment of colorectal cancer. However, both innate and acquired resistance mechanisms, including compensatory feedback loops, limit its efficacy. Nevertheless, the emergence of these feedback loops has remained largely unexplored to date. Here, we showed feedback upregulation of HER3 and induction of HER3 phosphorylation after cetuximab treatment in colon cancer cells. We also showed that this upregulation occurs, at least partly, through AKT inhibition. Together with this, we observed increased HER2:HER3 dimerization upon cetuximab treatment. Interestingly, lapatinib, a dual EGFR and HER2 tyrosine kinase inhibitor, blocked the increase of cetuximab-induced HER3 phosphorylation. Additionally, we showed that upon HER3 knockdown, cetuximab combined with lapatinib was able to decrease cell viability compared to HER3 expressing cells. These results suggest the existence of a cetuximab-induced feedback HER3 activation that could potentially result in reduced cetuximab efficacy in colorectal cancer patients. Taken together, we provide evidence of the limited effectiveness of cetuximab monotherapy compared to rational combinations.

| S-EPMC5354831 | biostudies-literature

Relief of feedback inhibition of HER3 transcription by RAF and MEK inhibitors attenuates their antitumor effects in BRAF mutant thyroid carcinomas.

2013-02-01 | GSE37441 | GEO

Regulation of ERBB3/HER3 signaling in cancer.

Project description:ERBB3/HER3 is emerging as a molecular target for various cancers. HER3 is overexpressed and activated in a number of cancer types under the conditions of acquired resistance to other HER family therapeutic interventions such as tyrosine kinase inhibitors and antibody therapies. Regulation of the HER3 expression and signaling involves numerous HER3 interacting proteins. These proteins include PI3K, Shc, and E3 ubiquitin ligases NEDD4 and Nrdp1. Furthermore, recent identification of a number of HER3 oncogenic mutations in colon and gastric cancers elucidate the role of HER3 in cancer development. Despite the strong evidence regarding the role of HER3 in cancer, the current understanding of the regulation of HER3 expression and activation requires additional research. Moreover, the lack of biomarkers for HER3-driven cancer poses a big challenge for the clinical development of HER3 targeting antibodies. Therefore, a better understanding of HER3 regulation should improve the strategies to therapeutically target HER3 for cancer therapy.

| S-EPMC4279368 | biostudies-literature

Highly Selective and Potent Thiophenes as PI3K Inhibitors with Oral Antitumor Activity.

Project description:Highly selective PI3K inhibitors with subnanomolar PI3K? potency and greater than 7000-fold selectivity against mTOR kinase were discovered through structure-based drug design (SBDD). These tetra-substituted thiophenes were also demonstrated to have good in vitro cellular potency and good in vivo oral antitumor activity in a mouse PI3K driven NCI-H1975 xenograft tumor model. Compounds with the desired human PK predictions and good in vitro ADMET properties were also identified. In this communication, we describe the rationale behind the installation of a critical triazole moiety to maintain the intricate H-bonding network within the PI3K receptor leading to both better potency and selectivity. Furthermore, optimization of the C-4 phenyl group was exploited to maximize the compounds mTOR selectivity.

| S-EPMC4018126 | biostudies-literature

Melanoma adapts to RAF/MEK inhibitors through FOXD3-mediated upregulation of ERBB3.

Project description:The mechanisms underlying adaptive resistance of melanoma to targeted therapies remain unclear. By combining ChIP sequencing with microarray-based gene profiling, we determined that ERBB3 is upregulated by FOXD3, a transcription factor that promotes resistance to RAF inhibitors in melanoma. Enhanced ERBB3 signaling promoted resistance to RAF pathway inhibitors in cultured melanoma cell lines and in mouse xenograft models. ERBB3 signaling was dependent on ERBB2; targeting ERBB2 with lapatinib in combination with the RAF inhibitor PLX4720 reduced tumor burden and extended latency of tumor regrowth in vivo versus PLX4720 alone. These results suggest that enhanced ERBB3 signaling may serve as a mechanism of adaptive resistance to RAF and MEK inhibitors in melanoma and that cotargeting this pathway may enhance the clinical efficacy and extend the therapeutic duration of RAF inhibitors.

| S-EPMC3635724 | biostudies-literature

Upregulation of ERBB3 by FOXD3, an adaptive response to RAF and MEK inhibitors

Project description:To understand the transcriptional impact of FOXD3 in melanoma cells, we utilized a microarray approach. We collected RNA from three unrelated mutant B-RAF melanoma cell lines (WM115, WM793, and A375) that were engineered to inducibly express FOXD3 or the control gene, β-galactosidase (LacZ), after 5 days of transgene induction. This time point was chosen based on maximal phenotypic changes previously observed. Comparison of gene signatures between the 3 cell lines produced approximately 2,600 common genes differentially regulated by FOXD3-expressing cells compared to the LacZ controls. Three unrelated mutant B-RAF melanoma cell lines (WM115, WM793, and A375) were induced to express FOXD3 and compared against the same cell lines expressing the control gene, β-galactosidase (LacZ).

| S-ECPF-GEOD-43962 | biostudies-other

Upregulation of ERBB3 by FOXD3, an adaptive response to RAF and MEK inhibitors

Project description:To understand the transcriptional impact of FOXD3 in melanoma cells, we utilized a microarray approach. We collected RNA from three unrelated mutant B-RAF melanoma cell lines (WM115, WM793, and A375) that were engineered to inducibly express FOXD3 or the control gene, ?-galactosidase (LacZ), after 5 days of transgene induction. This time point was chosen based on maximal phenotypic changes previously observed. Comparison of gene signatures between the 3 cell lines produced approximately 2,600 common genes differentially regulated by FOXD3-expressing cells compared to the LacZ controls. Three unrelated mutant B-RAF melanoma cell lines (WM115, WM793, and A375) were induced to express FOXD3 and compared against the same cell lines expressing the control gene, ?-galactosidase (LacZ).

2013-03-31 | E-GEOD-43962 | biostudies-arrayexpress

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data