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Carmona, E.

Publications and source records attributed to Carmona, E..

4 recordsLinked to original sources

Identification of a new inhibitor of Ran GTPase with therapeutic value in epithelial ovarian cancer

Compiled research studies suggest that the small GTPase Ran is critical in cancer initiation and progression. Compounds that block Ran activity would be valuable for cancer treatment. Yet, to date, there is no inhibitor proven to be efficient and specific to Ran. Here, by learning lessons from the discovery of KRAS G12C inhibitors, we generated a structural model of the switch II pocket of GDP-bound Ran to identify potential inhibitors of Ran by virtual screening. After in vitro verification, compound M26 was detected. Subsequent hit optimization lead us to identify compound M36 as an inhibitor of Ran with a promising therapeutic value. Binding of M36 to Ran was confirmed by cellular thermal shift assay. The specificity of M36 towards Ran was demonstrated by the evaluation of the active GTP-bound forms of a range of GTPases including Ran, RhoA, Cdc42 and Rac1; and by the expression of a dominant active mutant of Ran. Remarkably, similar to depletion of Ran by siRNA, M36 exhibits a specific toxicity in aneuploid ovarian cancer cells and represses DNA repair systems. In accordance with this, we demonstrated a synergistic relationship between M36 and the FDA approved PARP inhibitor Olaparib. In vivo, M36 presents acceptable pharmacokinetic properties and, more importantly, inhibits the tumor growth of an aggressive epithelial ovarian cancer xenograft model. Clinically relevant, M36 was able to induce cell death in ex vivo EOC patient derived micro-dissected tumor. Overall, our study is the first to provide a small-molecule compound inhibitor of Ran with a promising therapeutic potential.

cancer biology↗

Dataset of emerging contaminants in surface water, bottom water, porewater, and sediment: Urban and aquaculture impacts in the central and southern coast of Chile

Synthetic organic chemicals, including pesticides, pharmaceuticals, and industrial compounds, pose a growing threat to marine ecosystems as they enter through a variety of pathways, including direct discharges of wastewater (untreated or treated) from industrial, agricultural, and urban sources. Additionally, runoff from residential and agricultural land, as well as inland waterways, transport these chemicals to coastal zones. Despite their potential impact, data on the co-occurrence of these contaminants in the marine environment remains limited. Such information is critical for assessing coastal chemical status, establishing environmental quality benchmarks, and conducting comprehensive environmental risk assessments. In this study, we describe a multifaceted monitoring campaign targeting pesticides, pharmaceuticals, and industrial chemicals along the central-south coast and in northern Patagonia, Chile. Surface water, bottom water, porewater, and adjacent sediment samples were collected for analysis. Our results show the detection of up to 83 chemicals in surface water, 71 in bottom water, 101 in porewater, and 244 in sediments. To enhance data utility, we provide valuable information on the mode of action and molecular targets of the identified chemicals. This comprehensive dataset contributes to defining pollution fingerprints in coastal areas of the Global South, including remote regions in Patagonia. It serves as a critical resource for future research, policymaking, and the advancement of environmental protection in these regions.

pharmacology and toxicology↗

A senescence-like state is beneficial for ovarian cancer treatment

High-grade serous ovarian carcinoma (HGSOC) commonly responds to initial therapy, but this response is rarely durable. Understanding cell fate decisions taken by HGSOC cells in response to treatment could guide new therapeutic opportunities. Here we find that tissue-derived primary HGSOC epithelial cultures reflecting the original disease primarily undergo therapy-induced senescence in response to DNA damage and first-line carboplatin/paclitaxel chemotherapy. Unlike previous observations using cell lines, primary HGSOC cell TIS displays a stable senescence proliferation arrest and p16INK4A expression, and is accompanied by persistent DNA damage, an inflammatory secretome, and senolytic sensitivity, suggesting new avenues for selective pharmacological manipulation of these cells. Whether cell senescence induced by cancer therapy is beneficial or detrimental to clinical outcomes remains unknown. Single cell comparison of pre- and post-chemotherapy patient HGSOC tissue samples revealed changes in physio-pathological senescence biomarkers supporting a post-treatment senescence-like state. Importantly, patients with stronger senescence signatures post-chemotherapy displayed better 5-year survival suggesting that senescence accounts, at least in part, for beneficial cellular responses to treatment. Given that ovarian cancer epithelial cells almost universally retain the capacity to undergo senescence and that senescence appears beneficial in this context, HGSOC senescence-centric therapeutic avenues should be further explored. Author SummaryWhether cancer therapy-induced cell fate decisions like senescence are good or bad for patient treatment outcome is unknown. We find that ovarian cancer cells almost universally retain senescence competence and that senescence in treated cancer tissues correlate with good clinical outcomes. This reveals that senescence is a relevant drug target in ovarian cancer.

cancer biology↗

Cellular senescence is a central response to cytotoxic chemotherapy in high-grade serous ovarian cancer

High-grade serous ovarian cancer (HGSOC) commonly responds to initial therapy, but this response is rarely durable. Understanding cell fate decisions taken by HGSOC cells in response to treatment could guide new therapeutic opportunities. Here we find that primary HGSOC cultures undergo therapy-induced senescence (TIS) in response to DNA damage induced by chemotherapy. HGSOC-TIS displays most senescence hallmarks including persistent DNA damage, senescence-associated inflammatory secretome, and selective sensitivity to senolytic Bcl-2 family inhibitors, suggesting avenues for preferential synergistic clearance of these cells. Comparison of pre- and post-chemotherapy HGSOC patient tissue samples revealed changes in senescence biomarkers suggestive of post-treatment \"in patient\" TIS, and a stronger TIS response in post-chemotherapy tissues correlated with better 5-year survival rates for patients. Together, these data suggest that the induction of cellular senescence in HGSOC cells accounts at least in part for beneficial cellular responses to treatment in patients providing a new therapeutic target.\n\nOne Sentence SummaryCellular senescence is a central beneficial response to chemotherapy in high-grade serous ovarian cancer both in vitro and in patient.

cancer biology↗