Evolutionary exploitation of PD-L1 expression in hormone receptor positive breast cancer

West, J.; Park, D.; Harmon, C.; Williamson, D.; Ashcroft, P.; Maestrini, D.; Ardaseva, A.; Bravo, R.; Sahoo, P.; Khong, H.; Luddy, K.; Robertson-Tessi, M.

doi:10.1101/454447

bioRxiv · 10.1101/454447

Evolutionary exploitation of PD-L1 expression in hormone receptor positive breast cancer

West, J.·Park, D.·Harmon, C.·Williamson, D.·Ashcroft, P.·Maestrini, D.·Ardaseva, A.·Bravo, R.·Sahoo, P.·Khong, H.·Luddy, K.·Robertson-Tessi, M.

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Abstract

Based on clinical data from hormone positive breast cancer patients, we determined that there is a potential tradeoff between reducing tumor burden and altering metastatic potential when administering combination therapy of aromatase inhibitors and immune checkpoint inhibitors. While hormone-deprivation therapies serve to reduce tumor size in the neoadjuvant setting pre-surgery, they may induce tumors to change expression patterns towards a metastatic phenotype. We used mathematical modeling to explore how the timing of the therapies affects tumor burden and metastatic potential with an eye toward developing a dynamic prognostic score and reducing both tumor size and risk of metastasis.

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West, J., Park, D., Harmon, C., Williamson, D., Ashcroft, P., Maestrini, D., Ardaseva, A., Bravo, R., Sahoo, P., Khong, H., Luddy, K., Robertson-Tessi, M.. 2018-10-26. Evolutionary exploitation of PD-L1 expression in hormone receptor positive breast cancer. https://doi.org/10.1101/454447

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