Biology subjects

McKenna, D.

Publications and source records attributed to McKenna, D..

2 recordsLinked to original sources

bioRxiv2021

CaV1.3 enhanced store operated calcium promotes resistance to androgen deprivation in prostate cancer

Androgen deprivation therapy (ADT) is the main treatment for advanced prostate cancer (PCa) but resistance results in progression to terminal castrate resistant PCa (CRPC), where there is an unmet therapeutic need. Aberrant intracellular calcium (Cai2+) is known to promote neoplastic transformation and treatment resistance. There is growing evidence that expression of voltage gated calcium channels (VGCC) is increased in cancer, particularly the CACNA1D/CaV1.3 in CRPC. The aim of this study was to investigate if increased CaV1.3 drives resistance to ADT and determine its associated impact on Cai2+ and cancer biology. Bioinformatic analysis revealed that CACNA1D gene expression is increased in ADT treated PCa patients regardless of TMPRSS2:ERG status. Corroborated in both in vivo LNCaP xenograft mouse and in vitro PCa cell line models which demonstrated a significant increase in CaV1.3 protein expression following ADT with bicalutamide. The expression was found to be a shortened 170kDA CaV1.3 isoform associated which failed to mediate calcium influx following membrane depolarisation. Instead, under ADT CaV1.3 mediated a rise in basal cytosolic calcium and an increase in store operated calcium entry (SOCE). This in turn drove both proliferation and survival of long-term ADT CRPC cells. Overall, this study demonstrates for the first time in PCa that increased SOCE through a novel CaV1.3 mechanism which represents a novel oncogenic switch that contributes to ADT resistance and promotes CRPC biology. Highlighting aberrant intracellular calcium in CRPC as a potential area for therapeutic development to improve patient outcomes.

cancer biology↗

bioRxiv2021

Hitting more birds with one stone: CD70 as an actionable immunotherapeutic target in recurrent glioblastoma

PurposeGlioblastoma (GBM) patients suffer from a dismal prognosis, with standard of care therapy inevitably leading to therapy-resistant recurrent tumors. The presence of brain tumor initiating cells (BTICs) drives the extensive heterogeneity seen in GBM, prompting the need for novel therapies specifically targeting this subset of tumor-driving cells. Here we identify CD70 as a potential therapeutic target for recurrent GBM BTICs. Experimental DesignIn the current study, we identified the relevance and functional influence of CD70 on primary and recurrent GBM cells, and further define its function using established stem cell assays. We utilize CD70 knockdown studies, subsequent RNAseq pathway analysis, and in vivo xenotransplantation to validate CD70s role in GBM. Next, we developed and tested an anti-CD70 CAR-T therapy, which we validated in vitro and in vivo using our established preclinical model of human GBM. Lastly, we explored the importance of CD70 in the tumor immune microenvironment (TIME) by assessing the presence of its receptor, CD27, in immune infiltrates derived from freshly resected GBM tumor samples. ResultsCD70 expression is elevated in recurrent GBM and CD70 knockdown reduces tumorigenicity in vitro and in vivo. CD70 CAR-T therapy significantly improves prognosis in vivo. We also found CD27 to be present on the cell surface of multiple relevant GBM TIME cell populations. ConclusionCD70 plays a key role in recurrent GBM cell aggressiveness and maintenance. Immunotherapeutic targeting of CD70 significantly improves survival in animal models and the CD70/CD27 axis may be a viable poly-therapeutic avenue to co-target both GBM and its TIME.

cancer biology↗