Abstract 3935: Involvement of nanoscale physical communication in obesity-associated breast cancer severity
Authors: Saha Tanmoy , Srinivasan Balaaji Baanupriya , Sengupta Shiladitya 
Published: March 2024

Obesity is a risk factor for several cancers, including breast cancer, and contributes up to 20% of cancer-related deaths. Growing evidence from both clinical and preclinical studies indicates that increased obesity is associated with increases in cancer incidence, progression, metastasis, and therapeutic resistance. According to the Centers for Disease Control and Prevention (CDC), more than 70% and 40% of American adults can be classified as overweight and obese, respectively. However, treatment strategies for dealing with cancer in obese patients have not advanced apart from lifestyle interventions. However, several signaling mechanisms have been proposed related to the inflammatory and metabolic impact of obese adipocytes in promoting cancer progression. However, a lack of mechanistic understanding led to no specific treatment strategies have been proposed which can specifically downregulate the key regulator by which obese adipocytes promote cancer progression. Thus, translational research initiatives are immediately needed to provide mechanistic justifications for these striking statistics in order to better serve this growing segment of the population.

Here, we have shown the role of nanoscale physical communication between breast cancer cells and adipose tissue in promoting cancer progression. Using high-resolution optical and electron microscopy, we have found that breast cancer cells form nanoscale tubular communications with obese adipocytes. Moreover, the cancer cells hijack mitochondria from obese adipocytes. However, coculturing cancer cells and obese adipocytes in the Boyden chamber, allowing exosomal and paracrine communication but blocking direct physical communication, revealed negligible mitochondria transfer. This observation indicates an active transfer of mitochondria via nanotube. A significantly higher rate of mitochondria transfer from obese adipocytes to cancer cells has been observed than non-differentiated pre-adipocytes. The transfer of mitochondria results in an increase in the metabolism of the cancer cells. The mechanistic investigation of the nanotube formation revealed actin's presence as the major component in the nanotube. The exocyst-GTPase protein complex has a prime contribution in actin remodeling and nanotube formation. Inhibition of exocyst-GTPase using a pharmacological inhibitor results in a significant reduction in nanotube-mediated mitochondria transfer.

Conclusion: Our goal is to (i) investigate the direct physical connection between adipocytes and cancer cells and the effect on cancer progression and (ii) eliminate mortality related to obesity-associated breast cancer severity by introducing a new therapeutic strategy. Here, we have shown how cancer cells communicate with obese adipocytes and receive additional metabolic power for proliferation. The in vivo investigation of the same is under progress.

Citation Format: Tanmoy Saha, Balaaji Baanupriya Srinivasan, Shiladitya Sengupta. Involvement of nanoscale physical communication in obesity-associated breast cancer severity [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(6_Suppl):Abstract nr 3935.