The study included 36 people with advanced pancreatic cancer, some of whom had received standard chemotherapy, while others had received chemotherapy along with Paricalcitol, a synthetic compound that is considered an analog of vitamin D.
The results showed that combining chemotherapy with Paricalcitol is safe and helps to weaken the protective environment surrounding the tumor, which is a dense fibrous tissue that surrounds the tumor and prevents drugs and immune cells from penetrating it. The researchers found that Paricalcitol inhibits the activity of these fibroblasts, while simultaneously increasing the ability of immune T cells to penetrate the tumor, making it more susceptible to treatment.
Although the study included a small number of patients, its results were encouraging, as a partial response to treatment was observed in 42% of patients who received Paricalcitol with chemotherapy, compared to only 9% of those who received chemotherapy alone. The progression of the disease was also halted for a full year in some patients.
The researchers emphasize that it is too early to talk about a new treatment standard, but this study shows that vitamin D analogs are able to "reprogram" the tumor microenvironment and make it less resistant to treatment.
