A recent study by cancer researcher Chawnshang Chang, Ph.D., provides additional proof of a concept he’s been investigating for years: that the environment surrounding a prostate tumor plays a major role in metastasis, and new treatments should be designed to target that environment as well as the tumor itself.
Published by the International Journal of Oncology, Chang’s laboratory found that bone marrow derived stem cells, which are recruited to the site of a growing tumor, are able to convert nearby normal fibroblast cells into cancer cells, resulting in tumor metastasis. The conversion process sets up dangerous new ways for the cancer to spread.
“Investigators are starting to realize that tumor proliferation and tumor migration are two different things and should be treated as such,” said Chang, the George Hoyt Whipple Distinguished Professor of Pathology, Urology, and Radiation Oncology at the University of Rochester and Wilmot Cancer Institute.
Prostate cancer is the most common cancer among men in the United States. It has several subtypes, and one type called castrate-resistant prostate cancer (CRPC) eludes the most aggressive treatments including androgen deprivation therapy. Chang’s lab focuses on trying to understand why CRPC tumors always return, even after a period of remission.
He has already made several landmark discoveries while focusing on the androgen receptor (AR), the molecule responsible for fueling prostate cancer.
The latest paper suggests the microenvironment—the neighborhood of cells surrounding the tumor—is where stem cells can be recruited through altered cytokine-AR signals to boost prostate cancer metastasis. Interestingly, Chang said, his laboratory also discovered that although androgen deprivation therapy shrinks tumors, it also might inadvertently promote cell metastasis due to altered cell signaling in the region of the tumor.
Chang data’s suggests several targeted treatment possibilities, by either interrupting the conversion process, or preventing the recruitment of stem cells from taking place.