Abstract 3824: Remodeling of anaplastic thyroid cancer cell signaling and immune landscape by natural alkaloid berberine

Abstract

Anaplastic thyroid cancer (ATC) is universally diagnosed as Stage IV with a five-year-survival of 4%, illuminating its dreadful prognosis. ATC is undifferentiated, has an inflammatory tumor microenvironment (TME), and metabolic dysregulation. As it is refractory to all established therapies, we propose a novel therapeutic - Berberine (BBR), a natural plant alkaloid, with numerous cellular targets that can potentially reprogram ATC’s aggressive phenotype. This research comprehensively examines the multitarget efficacy of BBR. Following initial dose response studies, all assays used 100µM concentration of BBR or DMSO vehicle control for 24-hour exposure. To model the ATC tumor microenvironment, monocyte cell line U937 cells were activated and polarized into a proinflammatory macrophage phenotype. In the presence of berberine at the activation and polarization stages, 33 soluble inflammatory mediators were downregulated in the conditioned media compared to controls. Targeting the aggressiveness of anaplastic disease, berberine slowed proliferation by 50% selectively in ATC cells from 48 to 72 hours, while sparing the immortalized normal thyroid cells. BBR also delayed wound healing by 30% in ATC cells after 24, 48, and 72 hours. These observations were substantiated by Western blot analysis of ATC and immortalized normal cells where BBR decreased phosphorylation of MEK, ERK, and ribosomal protein S6, crucial downstream regulators of the pro-proliferative and pro-survival pathways and increased phosphorylation of AMPKα, activating its anti-tumor and regulatory effects. Validation of in vitro findings via RNA-Seq was conducted by Genewiz from Azenta Life Sciences and Qiagen’s Ingenuity Pathway Analysis was used for in silico modeling. Greater than 400 significantly differentially expressed genes were identified suggesting that BBR regulates mitochondrial metabolism, cholesterol biosynthesis, glycometabolism, apoptosis, inflammation, and proliferation. BBR’s ability to alleviate inflammatory mediators in the TME, depress overactive cell signaling, and regulate metabolism to make it a more targetable cancer reveals it as an interesting candidate to prime ATC for combination therapy. Citation Format: Tara Jarboe, Kaci Kopec, Nicole R. DeSouza, Jan Geliebter, Raj K. Tiwari, Xiu-Min Li. Remodeling of anaplastic thyroid cancer cell signaling and immune landscape by natural alkaloid berberine. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3824.