Abstract 3165: Targeting angiogenesis for improved survival in mantle cell lymphoma

Abstract Mantle cell lymphoma (MCL) is a subtype comprising 6% of all NHL cases and is characterized by overexpression of cyclin D1 due to chromosomal translocation t (11;14) in the nodal MCL subtype. One of the best discriminatory genes between these conventional and indolent MCL tumors is SOX11; in addition, SOX11 has been shown to promote angiogenesis in MCL. Further SOX11 protein expression in MCL patients correlated with increased microvascular density and poor outcomes. Bulk transcriptomics analysis was performed on MCL patients (n=24) and CD19-purified B cells from healthy donors (HD, n=3). To understand the role of the angiogenic process in MCL, we queried 141 genes related to angiogenesis (GO: 0001525). Our analysis showed that many genes involved in angiogenesis were predominantly overexpressed in MCL compared to HD, including FLT1 and KDR (p-value;0. 05; FC2). SOX11 has been shown to regulate PDGFA in MCL cell lines. Consistent with this observation, we also see upregulated PDGFA levels in MCL patients. However, PDGFA upregulation was not statistically significant in our analysis. Further expression of VEGFR2 is overexpressed in MCL Patients (n=122) compared to naïve or activated-B cells from HD. We validated that VEGFR2 protein levels were higher in MCL primary patients than in healthy donor PBMC. Further, in two independent cohorts, high VEGFR2 expression shows significant adverse effects on 5-year overall survival (OS). To explore the potential of targeting VEGFR, we utilized lucitanib, which potently and selectively inhibits VEGFRs. Treatment with lucitanib resulted in a dose-dependent decrease in cell viability and cellular death as determined by Annexin PI staining; further, MCL cells treated with lucitanib showed inhibition of autophosphorylation of VEGFR2 and demonstrated PARP cleavage associated with cytotoxicity in-vitro. To assess the role of VEGFR2 inhibitor lucitanib as a single agent in MCL growth in-vivo, we utilized two different murine models of MCLs. First, we used cell-line-derived xenograft (CDX) models of MCL where Jeko-1 and HS5 cells were injected together, followed by treatment (lucitanib;15mg/kg QOD; IP) and measured tumor volume until the ERC of any experimental mice was reached. Kaplan-Meier survival graphs were plotted, demonstrating that lucitanib treatment prolongs survival in-vivo. Further, to confirm if the lucitanib can provide an overall survival benefit in the systemic PDX MCL model, we injected the PDX cells via the tail vein in NSG mice and followed human-B2M levels for disease progression, and overall survival was the endpoint. Lucitanib treatment significantly prolonged median overall survival significantly in the systemic MCL model. Our data demonstrates that targeting angiogenesis in MCL can provide therapeutic benefits, as demonstrated in preclinical MCL models. Citation Format: Satishkumar Singh, Anuvrat sircar, Audrey Odier, Narendranath Epperla, Natarajan Muthusamy, Samir Parekh, Lalit Sehgal. Targeting angiogenesis for improved survival in mantle cell lymphoma abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 3165.