bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2022.12.27.522019

ONC201/TIC10 enhances durability of mTOR inhibitor everolimus in metastatic ER+ breast cancer

Farmaki, E.·Nath, A.·Emond, R.·Karimi, K. L.·Grolmusz, V. K.·Cosgrove, P. A.·Bild, A. H.
View original source ↗Export metadata ↓

Abstract

The mTOR inhibitor, everolimus, is an important clinical management component of metastatic ER+ breast cancer. However, most patients develop resistance and progress on therapy, highlighting the need to discover strategies that increase mTOR inhibitor effectiveness. We developed ER+ breast cancer cell lines, sensitive or resistant to everolimus, and discovered that combination treatment of ONC201/TIC10 with everolimus inhibited cell growth in 2D/3D in vitro studies. We confirmed increased therapeutic response in primary patient cells progressing on everolimus, supporting clinical relevance. We show ONC201/TIC10, in metastatic ER+ breast cancer cells, mechanistically involves oxidative phosphorylation inhibition and stress response activation. Transcriptomic analysis in everolimus resistant breast patient tumors and mitochondrial functional assays in resistant cell lines demonstrated increased mitochondrial respiration dependency, contributing to ONC201/TIC10 sensitivity. We propose that ONC201/TIC10 and modulation of mitochondrial function may provide an effective add-on therapy strategy for patients with metastatic ER+ breast cancers resistant to mTOR inhibitors.

Source connections

Explore related subjects

cancer biologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Farmaki, E., Nath, A., Emond, R., Karimi, K. L., Grolmusz, V. K., Cosgrove, P. A., Bild, A. H.. 2022-12-27. ONC201/TIC10 enhances durability of mTOR inhibitor everolimus in metastatic ER+ breast cancer. https://doi.org/10.1101/2022.12.27.522019

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Epigenetic progression of pancreatic cancer to aggressive subtypes involves alternate routes of lineage reprogramming in subtype-intermediate progenitor cells

Pancreatic ductal adenocarcinoma (PDAC) progression involves malignant cell state plasticity. Epigenetic changes underlie this plasticity, yet the PDAC cis-regulatory landscape remains understudied. To address this, we profiled 33 primary tumors and 7 metastases from 39 patients with single-cell ATAC-seq, paired with 10 single-cell RNA-seq profiles. We found that epigenetic GATA6+/KRT17+ co-accessibility identifies a classical-basal subtype-intermediate progenitor state (SIP) associated with better clinical outcomes. SIP cells display limited epigenetic reprogramming from premalignant epithelium and retain gastric-intestinal differentiation reminiscent of neoplastic precursors. Lineages without GATA6+/KRT17+ co-accessibility exhibit greater lineage and epithelial-mesenchymal plasticity. Classical PDACs that repress basal gene accessibility activate neural-like progenitor (NRP) and tuft lineage enhancers, whereas basal committed tumors display esophageal transdifferentiation. Compared to SIP, classical-NRP and basal committed tumors have poorer outcomes, and show distinct PD-1/PD-L1 immune proteomic phenotypes and prognostic myofibroblast epigenetic states, respectively. Our work reveals links between lineage reprogramming, EMT, and epigenetic progression in human PDAC.

cancer biology↗
bioRxiv2026

Tissue resident CD4+ memory T-cells mark response to immune checkpoint inhibition in high-grade glioma

Background: Immune checkpoint inhibitors (ICI) are efficacious in many solid tumors, but response in glioma is restricted to a small subgroup. The determinants of response and resistance to ICI remain poorly understood. Methods: Here we exploit a syngeneic hypermutated high-grade glioma model with dichotomous response to combined PD-1 and CTLA-4 inhibition to unravel determinants of tumor-infiltrating T-cells driving response. Tumor-infiltrating T-cells from ICI-responsive and non-responsive tumors were analyzed by single-cell RNA and T-cell receptor sequencing and tumor-reactive T-cell receptor clonotypes were functionally validated to characterize their transcriptional phenotypes. We verify our findings in IDH1 wildtype glioblastoma patients treated with neoadjuvant pembrolizumab. Results: ICI response was associated with intratumoral clonal expansion of tumor-reactive cytotoxic T-cells and increased infiltration of CXCR6+ CD4+ tissue resident memory T-cells (Trm). CD4 stem-like memory T-cells in responding tumors demonstrated elevated interferon responses, following trajectories toward clonally expanded Trm, versus trajectories toward exhaustion in non-responsive tumors. In responsive tumors, CD4+ Trm interacted with infiltrating CXCR3+ tumor-reactive and clonally expanded, yet transcriptionally versatile cytotoxic T-cells. Probing the post neoadjuvant ICI high-grade glioma patient tissue dataset, we confirmed increased CXCR6 expression in CD4+ T cells and the association of CD4+ Trm with prolonged overall survival. Conclusion: These findings identify CD4 tissue-resident memory T-cells as determinants of ICI response in IDH1 wildtype high-grade glioma and warrant their further investigation to improve immunotherapy outcomes.

cancer biology↗
bioRxiv2026

Low-dose doxorubicin drives caveolin-1 depended re-epithelialization of breast cancer cells as a mechanism of cancer plasticity

Breast cancer progression is driven by dynamic changes in epithelial plasticity, membrane organization, and intracellular signaling, yet the effects of sustained low-dose chemotherapy on these processes remain poorly understood. Here, we investigated the impact of prolonged low-dose doxorubicin on membrane remodeling, epithelial phenotype, membrane-associated Ras lipid-anchor localization, and autophagy in mesenchymal-like MDA-MB-231 breast cancer cells. Low-dose doxorubicin significantly increased Caveolin-1 expression and enhanced E-cadherin protein levels, accompanied by a transition toward a more compact epithelial-like morphology with increased cell-cell contacts. Live-cell imaging demonstrated a significant reduction in the membrane-to-cytoplasm fluorescence ratio of the lipid-anchored GFP-tH probe, indicating redistribution from the plasma membrane to the cytoplasm following treatment. Analysis of autophagy-related proteins revealed decreased LC3-I together with increased LC3-II, ATG5, and p62 expression, consistent with autophagosome accumulation and impaired autophagic flux. Collectively, our findings demonstrate that low-dose doxorubicin promotes extensive remodeling of plasma membrane organization, epithelial plasticity, membrane-associated lipid-anchor localization, and autophagy. This integrated response reveals previously unrecognized links between membrane architecture, Ras membrane association, and autophagy during phenotypic reprogramming of breast cancer cells, providing mechanistic insight into cellular adaptations elicited by sub-cytotoxic doxorubicin exposure.

cancer biology↗