RESUMO
Aim: To evaluate real-world data on treatment patterns in Argentina and Brazil in patients with ovarian cancer. Methods: This study evaluated de-identified antineoplastic exposure data from a private healthcare provider in Argentina and health claims database (Orizon) in Brazil from 2010 to 2019 and 2015 to 2020, respectively. Results: Platinum-based chemotherapy was the most common first-line therapy (Argentina: n =311 [87.6%]; Brazil: n = 1142 [79.3%]). The proportion of patients receiving platinum-based chemotherapy declined across both populations from first- to second-line, while use of non-platinum-based, targeted, and hormone therapies increased. Duration of platinum-based treatment and time to next treatment decreased from first- to fourth-line. Conclusion: There is an unmet need for effective therapies that can prolong time to next treatment in ovarian cancer in Argentina and Brazil.
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RESUMO
BRCA2 is a well-established cancer driver in several human malignancies. While the remarkable success of PARP inhibitors proved the clinical potential of targeting BRCA deficiencies, the emergence of resistance mechanisms underscores the importance of seeking novel Synthetic Lethal (SL) targets for future drug development efforts. In this work, we performed a BRCA2-centric SL screen with a collection of plant-derived compounds from South America. We identified the steroidal alkaloid Solanocapsine as a selective SL inducer, and we were able to substantially increase its potency by deriving multiple analogs. The use of two complementary chemoproteomic approaches led to the identification of the nucleotide salvage pathway enzyme deoxycytidine kinase (dCK) as Solanocapsine's target responsible for its BRCA2-linked SL induction. Additional confirmatory evidence was obtained by using the highly specific dCK inhibitor (DI-87), which induces SL in multiple BRCA2-deficient and KO contexts. Interestingly, dCK-induced SL is mechanistically different from the one induced by PARP inhibitors. dCK inhibition generates substantially lower levels of DNA damage, and cytotoxic phenotypes are associated exclusively with mitosis, thus suggesting that the fine-tuning of nucleotide supply in mitosis is critical for the survival of BRCA2-deficient cells. Moreover, by using a xenograft model of contralateral tumors, we show that dCK impairment suffices to trigger SL in-vivo. Taken together, our findings unveil dCK as a promising new target for BRCA2-deficient cancers, thus setting the ground for future therapeutic alternatives to PARP inhibitors.
