Intratumoral TYME 18 Administration Suppresses Tumor Cell Proliferation in Mice: An In Vivo Study

Tyme-18 is a formulation that combines a steroid acid, TUDCA, with surfactants such as N-methyl pyrrolidone, polidocanol, and linoleic acid. It is administered directly into tumors with the aim of causing tumor regression without harming the surrounding healthy tissue. The study conducted on Balb/C mice involved the inoculation of CT-26 cancer cells, followed by tumor establishment to a size of about 100 mm^3. The initial assessment was semi-quantitative and involved 10 animals, with a subsequent larger experiment that tested the individual components of Tyme-18.

In the study, mice received intra-tumoral injections of Tyme-18 with surfactants, surfactants alone without TUDCA, or a control solution, with measurements taken three times per week. The injections were given six times at intervals of three days, spanning a total of four weeks. The animals were sacrificed either when the tumor size reached 2000 mm^3 or at the end of the 16-week study period.

The results showed a significant difference in tumor regression between the Tyme-18 treated group and the untreated control group. A slight reduction in tumor mass was noted with the surfactant alone, but the most pronounced response was observed in the group treated with Tyme-18, which included both surfactants and TUDCA.

The discussion highlights that the local administration of the steroid acid in conjunction with surfactants hindered tumor growth. There was a synergistic effect observed between the surfactants and the steroid acid in reducing tumor size. Tyme-18 is being explored as a non-toxic treatment option for tumors where systemic therapy is not suitable.

The study also notes that ambiphilic steroid acids, aside from their physical and chemical effects, are recognized for their regulatory role in energy metabolism. They are known to influence receptors such as FXR, LXR, PPAR-α, and PPAR-γ, which are involved in regulating insulin utilization, insulin receptor sensitivity, and the transcription of genes related to glucose and lipid metabolism, as well as various immune responses. These effects could be beneficial in cancer treatment.