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Bjorge, L.

Publications and source records attributed to Bjorge, L..

3 recordsLinked to original sources

Single-Cell Transcriptomic Signatures Enable Stratified Combination Therapy for Platinum-Resistant Ovarian Cancer

In high-grade serous carcinoma (HGSC), extensive intra-tumoral heterogeneity hinders complete eradication and remains a major obstacle to developing combination therapies capable of eliminating subpopulations resistant to standard-of-care treatment. Using single-cell RNA sequencing of 72 samples from 54 HGSC patients spanning treatment-naive, post-neoadjuvant chemotherapy and relapse stages, we established a carboplatin-anchored framework that identifies transcriptional signatures of intrinsic (pre-existing) and adaptive (therapy-induced) resistance in individual tumors and prioritizes mechanistically matched drugs to potentiate carboplatin efficacy. Candidate compounds were ranked by integrating orthogonal resources--viability (GDSC, PRISM) and perturbational transcriptomics (L1000, Perturb-seq)--to reduce context bias. Among 64 candidates, three carboplatin adjuvants enhanced long-term efficacy in patient-derived organoids (PDOs), and pevonedistat further significantly reduced tumor burden in orthotopic xenografts. This tiered validation pipeline--from short-term and long-term PDOs and in vivo orthoptic xenografts--establishes a translational framework linking single cell resistance programs to actionable, tumor-specific, carboplatin-anchored combinations for HGSC.

cancer biology↗

Establishment of a humanized patient-derived xenograft mouse model of high-grade serous ovarian cancer for preclinical evaluation of combination immunotherapy

The limited efficacy of immunotherapy in clinical trials in high-grade serous ovarian cancer (HGSOC) may improve by implementing models more reflective of human biology into preclinical studies. To address this, we developed and validated a humanized patient-derived xenograft mouse model of HGSOC. Human hematopoietic stem cells and patient-derived HGSOC were engrafted into immunodeficient mice. The mice were administered durvalumab and/or oleclumab intraperitoneally semi-weekly for five weeks. The immunotherapy was well-tolerated, though no responses occurred. Leukocytes in primary tumors were analyzed immunohistochemically, and circulating T cells were characterized using spectral flow cytometry. All tumors exhibited an immune-excluded immunophenotype. No significant inter-group differences in disease burden, intratumoral leukocyte density, or circulating T-cells were observed. In the durvalumab-only group, tumor burden significantly positively correlated with intratumoral cytotoxic and regulatory T-cell densities. This model reflects human disease biology and clinical findings, providing a robust platform for studying tumor-immune interactions and immunosuppressive mechanisms in HGSOC.

cancer biology↗

Combining genome-wide studies of breast, prostate, ovarian and endometrial cancers maps cross-cancer susceptibility loci and identifies new genetic associations

We report a meta-analysis of breast, prostate, ovarian, and endometrial cancer genome-wide association data (effective sample size: 237,483 cases/317,006 controls). This identified 465 independent lead variants (P<5x10-8) across 192 genomic regions. Four lead variants were >1Mb from previously identified risk loci for the four cancers and an additional 23 lead variant-cancer associations were novel for one of the cancers. Bayesian models supported pleiotropic effects involving at least two cancers at 222/465 lead variants in 118/192 regions. Gene-level association analysis identified 13 shared susceptibility genes (P<2.6x10-6) in 13 regions not previously implicated in any of the four cancers and not uncovered by our variant-level meta-analysis. Several lead variants had opposite effects across cancers, including a cluster of such variants in the TP53 pathway. Fifty-four lead variants were associated with blood cell traits and suggested genetic overlaps with clonal hematopoiesis. Our study highlights the remarkable pervasiveness of pleiotropy across hormone-related cancers, further illuminating their shared genetic and mechanistic origins at variant- and gene-level resolution.

genetics↗