Ebrar Tutar-Torun

Glioblastoma multiforme (GBM) is an astrocytoma classified among the most aggressive brain tumors. Currently considered incurable, patients have a median survival of 15 months after diagnosis. Treatment typically involves tumor resection followed by radiotherapy and chemotherapy. Temozolomide is the most commonly used chemotherapeutic agent for GBM. Given the short median survival and the development of drug resistance to temozolomide, enhancing the efficacy of current treatments is of paramount importance. In this context, insulin is suggested as a supportive therapy to chemotherapy. It is hypothesized that insulin enhances the effectiveness of antimetabolite chemotherapies by prolonging the S phase. While insulin has been observed to extend the S phase in various cancers in the literature, its direct effect on the cell cycle in GBM has not been explored despite studies examining the impact of insulin on GBM by inhibiting insulin and IGF receptor gene function.In the MTT assay, cell survival decreased in groups treated with temozolomide (p

Treatment-refractory rectal cancer liver metastasis represents a major therapeutic challenge, particularly in the absence of actionable genomic biomarkers. Functional precision oncology approaches integrating genomic profiling with patient-derived organoid (PDO) drug testing may provide biologically informed therapeutic prioritization. A 50-year-old female patient with KRAS/TP53-mutant, microsatellite-stable (MSS) rectal adenocarcinoma refractory to FOLFIRINOX was enrolled. A liver metastasis from a treatment-refractory rectal cancer patient was processed to establish three-dimensional patient-derived organoids. Histopathological concordance was assessed using H&E and p53 immunohistochemistry. Comprehensive genomic profiling was performed using a 637-gene targeted next-generation sequencing panel, enabling detection of single-nucleotide variants, indels, copy number variations, microsatellite instability, and tumor mutational burden. Functional drug sensitivity profiling was conducted in parallel 2D and 3D platforms using a customized 17-agent panel, followed by exploratory combinatorial validation. The organoids demonstrated high phenotypic and genomic concordance with the parental tumor, preserving key driver alterations (KRAS^A146T, TP53^R175H, APC frameshifts, CCNE1 amplification), microsatellite stability, and low tumor mutational burden (TMB: 6.37 mut/Mb). Functional screening identified selective sensitivity to bevacizumab (IC₅₀: 0.130 μM), doxorubicin (IC₅₀: 0.570 μM), carboplatin (IC₅₀: 0.950 μM), and topotecan (IC₅₀: 1.600 μM) in the 3D organoid model, with consistent cross-platform validation. An exploratory combination assay further supported enhanced viability suppression under bevacizumab-based regimens. Critically, at the time of manuscript preparation, the patient demonstrated radiological disease stabilization under bevacizumab plus trastuzumab deruxtecan, consistent with the organoid-derived response profile. These findings highlight the capacity of integrated genomic and organoid-based profiling to uncover therapeutic vulnerabilities beyond standard biomarker assessment. This proof-of-concept case report study demonstrates the feasibility and translational relevance of an established organoid-based functional precision oncology platform for therapeutic prioritization in metastatic rectal cancer.