Okan Gultekin

Adaptive NK Cells Exhibit Tumor-Specific Immune Memory and Cytotoxicity in Ovarian Cancer

Abstract Adaptive NK (aNK) cells have emerged as a subset of NK cells with memory-like properties and specific cytotoxicity, offering promising therapeutic potential in cancer immunotherapy. In this study, we explored the role of aNK cells in high-grade serous ovarian cancer, focusing on their ability to establish tumor-specific immune memory and effectively target autologous tumors. Through a combination of in silico, in vitro, and ex vivo approaches, we demonstrated that aNK cells, in contrast to conventional NK cells, exhibit recall responses, specific cytotoxicity, and preferential infiltration into the tumor microenvironment. Our data revealed that aNK cells interact with dendritic cells within the tumor microenvironment via the HLA-E/NKG2C axis and CXCR2 signaling, contributing to their memory formation and tumor-targeting capabilities. These findings suggest that aNK cells could serve as potent agents in NK cell–based immunotherapies, particularly in solid tumors such as high-grade serous ovarian cancer, in which they resist immunosuppressive signals and maintain robust antitumor activity. This study provides new insights into the adaptive-like properties of aNK cells, underscoring their potential for advancing cancer immunotherapy strategies.

Mesothelin-Specific CAR T Cells Target Ovarian Cancer

Abstract New therapeutic options for patients with ovarian cancer are urgently needed. Therefore, we evaluated the efficacy of two second-generation mesothelin (MSLN)-directed CAR T cells in orthotopic mouse models of ovarian cancer. Treatment with CAR T cells expressing an MSLN CAR construct including the CD28 domain (M28z) significantly prolonged survival, but no persistent tumor control was observed. Despite lower response rates, MSLN-4–1BB (MBBz) CAR T cells induced long-term remission in some SKOV3–bearing mice. Tumor-infiltrating M28z and MBBz CAR T cells upregulated PD-1 and LAG3 in an antigen-dependent manner while MSLN+ tumor cells expressed the corresponding ligands (PD-L1 and HLA-DR), demonstrating that coinhibitory pathways impede CAR T-cell persistence in the ovarian tumor microenvironment. Furthermore, profiling plasma soluble factors identified a cluster of M28z- and MBBz-treated mice characterized by elevated T-cell secreted factors that had increased survival, higher CD8+ T-cell tumor infiltration, less exhausted CAR T-cell phenotypes, and increased HLA-DR expression by tumor cells. Altogether, our study demonstrates the therapeutic potential of MSLN-CAR T cells to treat ovarian cancer. Significance: These findings demonstrate that MSLN-directed CAR T cells can provide antitumor immunity against ovarian cancer.

Biomimetic organo-hydrogels reveal the adipose tissue local mechanical anisotropy regulates ovarian cancer invasion

Abstract High-grade serous ovarian cancer, the most common and aggressive ovarian cancer subtype, frequently metastasises to visceral adipose tissues. In these tissues, the extracellular matrix through which ovarian cancer cells migrate is constrained by the presence and preponderance of adipocytes. How cells migrate in this unique environment is not known, yet critical to understanding metastatic progression. To study these processes, we developed biomimetic organo-hydrogels that recreate structural, mechanical, and biochemical properties of human adipose tissues. We show that ovarian cancer cells present invasive tropism towards organo-hydrogels, replicating the behaviour observed in native adipose tissues. This migration is facilitated by the mechanical anisotropy and microstructure of organo-hydrogels and adipose tissues, allowing the formation of migratory tracks. These results highlight the contribution of adipocytes to tissue biophysical features as a key regulatory factor of ovarian cancer cell migration and demonstrate that organo-hydrogels are particularly relevant tools to develop in vitro models of complex tissue architectures with high cellularity.