Posted: Wednesday, April 26, 2023
Given that some breast cancer tumors are treated with heat to sensitize them to radiotherapy, investigators delved into possible cellular mechanisms that underlie this radiosensitivity. “Our data suggest that [this heat], hyperthermia, may exert its effects through arresting cells in the G2 phase, a particularly radiosensitive section of the cell cycle,” noted Hem D. Shukla, PhD, of the University of Maryland School of Medicine, Baltimore, and colleagues. They presented their findings at the American Association for Cancer Research (AACR) Annual Meeting 2023 (Abstract 1104/17) and called for further investigation.
The team also identified PTEN, a tumor suppressor overexpressed by up to 3.2-fold in vitro following hyperthermia, as a key gene that may regulate hyperthermia-induced radiosensitivity. “Understanding the genes and pathways responsible for the heat-induced sensitization of breast cancer will allow us to exploit genetic alterations in tumors and develop noninvasive thermoradiotherapy regimens that more specifically target the tumor,” continued Dr. Shukla and co-investigators. Thermoradiotherapy, they explained, significantly increases complete response rate and may provide a treatment modality for more aggressive types of breast cancer.
Overall, their work revealed distinct patterns of gene expression between breast cancer cells that were and were not treated with hyperthermia. They analyzed microarray data from four cell lines following treatment at 45° C for 30 minutes; three represented breast cancer and one represented nonmalignant mammary epithelial tissue.
Disclosure: The study authors reported no conflicts of interest.