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Kurppa, K. J.

Publications and source records attributed to Kurppa, K. J..

5 recordsLinked to original sources

Paired activity learning supports systematic identification of mutant-selective EGFR inhibitors

Acquired resistance to epidermal growth factor receptor (EGFR) inhibitors remains a major clinical challenge in non-small cell lung cancer (NSCLC), where successive rounds of therapy with first- and third-generation EGFR inhibitors often lead to increasingly resistant EGFR variants. In particular, EGFR L858R/T790M/C797S triple mutation renders tumors resistant to earlier-generation inhibitors, while disrupting the covalent engagement required by third-generation inhibitors such as osimertinib. Here, we developed an integrated computational-experimental framework for identifying compounds with differential activity between the triple-mutant EGFR and wild-type EGFR. Matched bioactivity measurements were leveraged to train a mutant-aware paired-activity regression framework, and the predicted candidates meeting stringent potency and mutant-preference criteria were subsequently evaluated using a support vector machine classifier for triple-mutant activity. Application of this sequential screening approach to 12 million molecules identified 16 consensus hits, including several previously reported inhibitors of drug-resistant EGFR variants. Based on their predicted differential activity and degree of prior characterization, five hit compounds were prioritized for initial biochemical evaluation, and two were selected for further biochemical, cellular and structural characterization. Mutant EGFR crystal structures in complex with the best-performing compounds revealed two distinct noncovalent binding modes within the ATP-binding cleft, demonstrating the ability of the framework to identify potent inhibitors with diverse binding modes. Together, this work illustrates how incorporating mutant-selectivity into a predictive framework as paired activities support the identification of mutant EGFR inhibitors and provide insights into their potency and selectivity. The discovered complementary structures provide experimentally defined templates for optimizing potency, mutant preference and drug-like properties of these and future compounds combating drug resistant NSCLC.

bioinformatics↗

YAP/TEAD drives treatment-induced adaptive immunosuppression in EGFR-mutant lung cancer

Residual disease remains a major obstacle for achieving durable responses in patients treated with oncogene-targeted therapy. Drug-tolerant persister (DTP) cells emerging under treatment and persisting in residual tumors are considered to be the root of acquired resistance, yet their contribution to immune evasion in on-treatment tumors is poorly defined. Here, we show in the context of EGFR-mutant lung cancer that DTP cells actively contribute to the formation of an immunosuppressive tumor microenvironment during EGFR tyrosine kinase inhibitor (TKI) therapy. In syngeneic mouse models and in patients, EGFR TKI therapy leads to an accumulation of immunosuppressive macrophages, which is strictly treatment-dependent and fully reversible upon treatment cessation or progressive disease, respectively. Quiescent DTP cells directly drive the recruitment and immunosuppressive reprogramming of monocytes and macrophages through a YAP-driven secretome, and the DTP-reprogrammed monocytes suppress T cell proliferation and effector functions in vitro. Co-targeting YAP with a TEAD inhibitor ORM-47286 rewires the DTP secretome and inhibits macrophage reprogramming in vitro, and prevents immunosuppressive macrophage accumulation and improves the efficacy of EGFR TKI therapy in immunocompetent mouse models. Our findings highlight the previously unappreciated role of DTP cells in modulating the tumor microenvironment in on-treatment tumors, and position the treatment-induced YAP/TEAD activity in DTP cells as an important driver of adaptive immunosuppression during EGFR-targeted therapy.

cancer biology↗

Pharmacokinetics and efficacy of tank-water administered BRAF-inhibitor dabrafenib in a zebrafish model of BRAF-mutant melanoma

Zebrafish models are widely used to study the biology of BRAF-mutant melanoma. However, long-term treatment of adult fish with small molecule BRAF inhibitors is challenging, limiting the usefulness of this model to study treatment-induced effects in melanoma biology. In addition, pharmacokinetic studies on small molecule inhibitors in zebrafish that could inform rational dosing strategies, are largely lacking. Here, we have assessed the pharmacokinetics, metabolism and efficacy of continuous tank water -administered BRAF-inhibitor dabrafenib in adult zebrafish. Our results demonstrate that dabrafenib is quickly absorbed from the tank water, reaching efficacious plasma levels within one hour following treatment, but also shows fast elimination kinetics with a half-life of 1.6 hours. We could detect most of the human metabolites of dabrafenib in zebrafish, suggesting that dabrafenib metabolism in zebrafish follows a similar process as in humans. Continuous tank water -administered dabrafenib led to therapeutically relevant steady-state plasma levels that inhibited the BRAF-driven signaling and growth in zebrafish melanoma cells in vitro, and resulted in robust in vivo efficacy in a genetic zebrafish model of BRAF-mutant melanoma, with no apparent toxicity. Together, our results demonstrate that continuous tank water -administered dabrafenib provides a feasible, efficient, and well-tolerated dosing strategy to study treatment-related effects in zebrafish models of BRAF-mutant melanoma. We expect that tank water-administration may also facilitate the dosing of other small molecule inhibitors, especially those with short in vivo half-life in zebrafish. HighlightsO_LIPharmacokinetic analysis demonstrates fast absorption kinetics and short plasma half-life for tank water -administered dabrafenib in zebrafish C_LIO_LIDabrafenib is metabolized in zebrafish following a similar metabolic process as in humans C_LIO_LITank water -administered dabrafenib provides a feasible, efficient, and well-tolerated dosing strategy to study treatment-related effects in zebrafish models of BRAF-mutant melanoma C_LIO_LITank water-administration may facilitate dosing of small molecule inhibitors with short in vivo half-life in zebrafish C_LI

cancer biology↗

Recurrent cancer-associated ERBB4 mutations are transforming and confer resistance to targeted therapies

Receptor tyrosine kinase ERBB4 (HER4) is frequently mutated in human cancer, and ERBB4 mutations have been identified in patients relapsing on targeted therapy. Here, we addressed the functional consequences of recurrent cancer-associated ERBB4 mutations that are located at regions important for dimer interactions and/or are paralogous to known oncogenic hotspot mutations in other ERBB genes. Eleven out of 18 analyzed mutations were transforming in cell models, thus suggesting oncogenic potential for more than half of the recurrent ERBB4 mutations. More detailed analyses of the most potent mutations, S303F, E452K and L798R, showed that they are activating, can co-operate with other ERBB receptors and are targetable with clinically available second-generation pan-ERBB inhibitors neratinib, afatinib and dacomitinib. Furthermore, the S303F mutation, together with a previously identified activating ERBB4 mutation, E715K, promoted resistance to third-generation EGFR inhibitor osimertinib in EGFR-mutant lung cancer model in vitro and in vivo. Together, these results are expected to facilitate clinical interpretation of the most recurrent cancer-associated ERBB4 mutations. The findings provide rationale for testing the efficacy of clinically used pan-ERBB inhibitors in patients harboring driver ERBB4 mutations both in the treatment-naive setting, and upon development of resistance to targeted agents.

cancer biology↗

Database of recurrent mutations (DORM), a web tool to browse recurrent mutations in cancers

Advances in sequencing technologies have facilitated the genetic characterization of large numbers of clinical cancer samples, leading to accumulation of extensive amounts of data. While potentially very useful for directing research and for clinical decision making, the increasing quantity of data generates challenges in its optimal management, and translation to informing clinical and research questions. Here, we present Database Of Recurrent Mutations (DORM), a database listing recurrent mutations (tissue-agnostic population frequency > 1) identified from cancer samples analyzed with whole genome or whole exome sequencing. The DORM database is a fast and feature-rich database supporting searching for several proteins, amino acid substitutions as well as queries using regular expressions.

bioinformatics↗