In a nutshell
The authors aimed to determine whether the detection of certain immune response cells in our body had any prognostic (outlook) significance.
Some background
T cells are an important part of our immune system. These cells are important for regulating the immune response to invading cells. The gene FOXP3 is necessary for the production of these cells. Some breast cancers overexpress (overproduce) FOXP3. This may cause immunotherapies (treatments that stimulate the immune system to attack cancer cells the same way it would attack a virus or bacteria) to be less effective.
Tumor-infiltrating lymphocytes (TILs) are immune cells found in tumors. TILs are involved in killing cancer cells, and higher levels of TILs have been associated with increased survival in breast cancer. Some TILs, however, also express FOXP3. It is not clear what effect these cells have on breast cancer prognosis.
Methods & findings
The aim of this study was to evaluate the significance of FOXP3, either within a tumor or in its environment. This study also aimed to determine whether these cells could predict the chances of survival in a breast cancer patient.
The results of 17 studies, including 8,277 patients with breast cancer, were evaluated.
Overall, patients with high levels of FOXP3 were 3.7 times more likely to have stage 3 breast cancer (spread to the lymph nodes) than stage 1, and 2.3 times more likely to be stage 3 than stage 2. Patients with high FOXP3 were 57% less likely to have hormone receptor positive (tumors dependent on the hormones estrogen or progesterone for growth) breast cancer. Tumors with high FOXP3 levels were 90% more likely to be dependent on the human epidermal growth factor receptor 2 (HER2) for growth. Patients with high FOXP3 levels were 2.5 times more likely to have triple negative (not dependent on hormones or HER2 for growth) than were patients with low FOXP3 levels.
Higher levels of FOXP3 were associated with the risk of recurrent cancer (cancer returning) in most subtypes. However, patients with triple negative breast cancer and high levels of FOXP3 were 50% more likely to have longer relapse-free survival.
The bottom line
The authors confirmed that high levels of FOXP3 could be associated with poor survival factors, such as a higher cancer stage, HR negative and HER2 positive tumors.
The fine print
This study is based on statistical data and not individual cases.
Published By :
BMC cancer
Date :
Oct 19, 2015
