Tumor Microenvironments May Encourage Treatment Resistance

A new study published in Nature Medicine is sending minor shock waves through the cancer community because it demonstrates that the method of thinking regarding chemotherapy treatments might not only be wrong, but actually making things worse.

A research team made up largely of researchers from the Division of Human Biology at the Fred Hutchinson Cancer Research Center in Seattle, Washington had their paper published on August 5 entitled "Treatment-induced damage to the tumor microenvironment promotes prostate cancer therapy resistance through WNT16B."

They identified "a spectrum of secreted proteins derived from the tumor microenvironment" that includes the expression of one such protein known as WNT16B. The expression of this protein appears to occur in the wake of DNA damage done to a cell, and its expression within the tissues surrounding a tumor, the so-called tumor microenvironment, had the effect of weakening cytotoxic chemotherapy, thereby "promoting tumor cell survival and disease progression."

They concluded that there is a cellular mechanism that goes into effect when chemotherapy treatments are given in a cyclical manner that "can enhance subsequent treatment resistance," that is derived from the tumor microenvironment.

In other words, it's not the cancer cells that are surviving the chemotherapy perse, but rather the healthy tissue surrounding the tumor that, when damaged by chemotherapy, appears to kick in a mechanism that helps the remaining cancer cells survive and allows the disease to progress.

This is contrary to expectations, in that resistance to chemotherapy was believed to be on account of adaptation of the tumor cells themselves, not on account of the tissues that make up the tumor microenvironment.

This research adds to the growing knowledge and understanding of the tumor microenvironment, which only recently became an area of anti-cancer research but has been steadily gaining steam ever since.

Source: Nature Medicine