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Cortes Gomez, E.

Publications and source records attributed to Cortes Gomez, E..

4 recordsLinked to original sources

A targetable opioid/cancer associated fibroblast axis drives extracellular matrix remodeling and tumor aggressiveness in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is an intractable disease with few effective treatment options. PDAC is characterized by a dense, fibro-inflammatory tumor microenvironment (TME) consisting mainly of cancer-associated fibroblasts (CAFs) and a CAF-generated collagen-rich extracellular matrix (ECM). As the ECM has profound impacts on tumor progression and therapy response, it is critical that we understand the mechanisms underlying ECM deposition and remodeling. In addition to a highly fibrotic and reactive TME, a hallmark of PDAC is pain. 93% of PDAC patients experience pain, and [~]70% are prescribed opioids for pain management during the course of their cancer treatment. Despite epidemiological evidence linking opioid use with diminished patient survival, how opioids impact tumor biology remains largely unknown. We now provide evidence that both endogenous and exogenous opioids drive ECM remodeling in the PDAC TME. We find that the commonly prescribed opioid morphine promotes the development of poorly differentiated tumors and increases collagen bundling and maturation in a mouse model of PDAC. Accordingly, RNA sequencing reveals that morphine induces significant upregulation of ECM genes and collagen modifying enzymes. We developed a morphine-induced gene signature which correlates significantly with the basal/mesenchymal subtypes of human PDAC and predicts worse overall survival in PDAC and other tumor types. Mechanistically, pharmacological inhibition and genetic knockdown of the mu opioid receptor (OPRM1) in CAFs attenuates expression of type 1a and type 3a collagens, and the myofibroblastic CAF marker alpha-SMA, demonstrating that opioid signaling is a direct regulator of CAF biology. Additionally, we provide the first evidence that CAFs produce endogenous opioids capable of activating OPRM1 and driving collagen expression. Finally, treatment with the FDA-approved peripherally restricted OPRM1 antagonist methylnaltrexone (MNTX) reduces desmoplasia, tumor weight, and ascites burden in a mouse model of PDAC. Therefore, we have identified a novel opioid-mediated signaling axis driving PDAC desmoplasia and reveal MNTX as a potential therapeutic to inhibit both exogenous and endogenous opioid-induced ECM remodeling and tumor aggressiveness.

cancer biology↗

Binary partitioning of human brain organization due to divergent human cytoskeletal evolution

CHRFAM7A is a biallelic uniquely human fusion gene present in 99.3% of humans. The direct and inverted alleles likely emerged independently in Africa and East Asia. We uncovered that the inverted allele regulates ULK4 expression through genetic epistasis. The increase in long to short ULK4 isoform ratio enhances -tubulin acetylation leading to microtubule (MT) cytoskeleton phenotypes (cell body: microtubule rich projections; neurite: de-bundling; growth cone: fanning with MT invasion). The MT cytoskeleton gain of function enhances neuronal arborization and functional connectivity in the human brain. Considering that the previously reported direct allele leads to actin cytoskeleton gain of function, we propose that CHRFAM7A alleles represent binary human genetic background through divergent evolution of the cytoskeleton. In the human brain the two alleles represent distinct brain organization: the direct allele enhances microstructure as measured by diffusion tensor imaging while the inverted allele increases functional connectivity with increased small world propensity. The two types of brain organization likely represent different susceptibility to neuropsychiatric disease and may underlie the allelic disease associations. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=195 HEIGHT=200 SRC="FIGDIR/small/725959v1_ufig1.gif" ALT="Figure 1"> View larger version (53K): org.highwire.dtl.DTLVardef@a84e75org.highwire.dtl.DTLVardef@1b712d9org.highwire.dtl.DTLVardef@367c01org.highwire.dtl.DTLVardef@1074dc4_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Reversible therapeutic resistance in EGFR mutant lung cancer caused by RB1 loss induced lineage plasticity

Treatment with EGFR tyrosine kinase inhibitors (EGFR TKI) is standard of care for patients with lung cancer initiated by activating mutations in the EGFR gene. While EGFR TKI treatment is effective, virtually all patients progress on therapy. Loss of function mutations in the RB1 tumor suppressor gene are associated with poor EGFR TKI outcomes, but underlying mechanisms remain unclear. Analysis of genetically engineered experimental models and human clinical specimens described here demonstrates RB1 loss has minimal impact on initial cell cycle responses to EGFR TKI but markedly accelerates acquired resistance over time. RB1 loss promotes transcriptional plasticity that enables rare cells to spontaneously assume reversible, resistance-conferring lineage states. These findings highlight the importance of non-genetic adaptations in driving acquired EGFR TKI resistance, advance our understanding of how RB1 impacts cancer, and identify opportunities to improve EGFR TKI treatment outcomes by targeting reversible epigenetic resistance mechanisms.

cancer biology↗

CPSF3 inhibition blocks pancreatic cancer cell proliferation through disruption of core histone processing

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with limited effective treatment options. This potentiates the importance of uncovering novel drug targets. We have discovered global dysregulation of the gene regulatory process alternative polyadenylation (APA) in PDAC. APA is a pre-mRNA processing mechanism that generates mRNAs with distinct 3 ends, impacting gene expression and protein function. We revealed that APA dysregulation in PDAC drives oncogenic signatures and predicts poor patient outcome. As APA directs widespread gene expression dysregulation across the PDAC patient population, we hypothesized that inhibition of APA has therapeutic potential. APA is controlled by a complex of proteins, including cleavage and polyadenylation specificity factor 3 (CPSF3). CPSF3 is the endonuclease catalyzing mRNA cleavage, and a potentially druggable target. We now find that CPSF3 is highly expressed and associated with poor prognosis in PDAC patients. CPSF3 knockdown decreases PDAC proliferation and clonogenicity in vitro and tumor growth in vivo. We demonstrate that CPSF3 knockdown induces widespread APA alterations of oncogenes and tumor suppressors, and determine the contribution of one of these events to CPSF3-induced cell proliferation phenotype. Furthermore, we find that PDAC, but not non-transformed pancreatic cells, are sensitive to the CPSF3 small molecule inhibitor JTE-607. Mechanistically, JTE-607 impairs replication-dependent histone processing, disrupting nucleosome assembly and destabilizing chromatin structure. Finally, we determine that JTE-607 attenuates cell proliferation by arresting cells in early S-phase of the cell cycle. Altogether, we identify CPSF3 as a druggable target in PDAC and reveal novel mechanisms by which CPSF3 controls cancer cell growth. SignificanceThis work identifies CPSF3 as a potential drug target in pancreatic ductal adenocarcinoma and reveals new mechanisms by which CPSF3 inhibition attenuates PDAC cell proliferation through modulating alternative polyadenylation and histone processing.

cancer biology↗