Abstract B09: Aspirin inhibits cyclooxygenase 2-mediated prostaglandin production and tumorigenesisin a preclinical model of tuberous sclerosis complex

Lymphangioleiomyomatosis (LAM) is a female predominant progressive and neoplastic disorder that leads to lung destruction and respiratory failure primarily in women. LAM is typically due to TSC2 mutations resulting in mTORC1 activation in proliferative smooth muscle-like cells in the lung. The female predominance of LAM suggests that estradiol contributes to disease development. Metabolomic profiling identified estradiol-enhanced prostaglandin biosynthesis signature in Tsc2-deficient cells, both in vitro and in vivo. Estradiol increased the expression of cyclooxygenase-2 (COX-2), a rate-limiting enzyme in prostaglandin biosynthesis, which was increased at baseline in TSC2-deficient cells, and was not affected by rapamycin treatment, but decreased by Torin 1 treatment and Rictor knockdown, associated with reduction of levels phospho-Akt (S473). Prostaglandin production was also increased in TSC2-deficient cells. In preclinical models, Celecoxib or aspirin treatment suppressed tumor progression. LAM patients had significantly higher serum prostaglandin levels than healthy women. 15-epi-lipoxin-A4 was identified in exhaled breath condensate from LAM subjects and was increased by aspirin treatment, indicative of functional COX-2 expression in the LAM airway. Targeting COX-2 and prostaglandin pathways may have therapeutic value in LAM and TSC-related diseases, and possibly in other conditions associated with mTOR-hyperactivation. Citation Format: Chenggang Li, Po-Shun Lee, Yang Sun, Xiaoxiao Gu, Erik Zhang, Chin-Lee Wu, Andrey Parkhitko, Neil Aurrichio, Tasha Morrison, John Blenis, Kai-Feng Xu, Elizabeth Petri Henske, Bruce Levy, David Kwiatkowski, Jane Yu. Aspirin inhibits cyclooxygenase 2-mediated prostaglandin production and tumorigenesisin a preclinical model of tuberous sclerosis complex. [abstract]. In: Proceedings of the AACR Special Conference: The Translational Impact of Model Organisms in Cancer; Nov 5-8, 2013; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2014;12(11 Suppl):Abstract nr B09.