Dynamic and significant changes of T-cell subgroups in breast cancer patients during surgery and chemotherapy

Breast cancer and its surgical treatment and chemotherapy have great impact on the immune system. This study aimed to monitor the various T cells in breast cancer patients and evaluate the immune functions.

Blood samples were collected from 249 breast cancer patients at the following time points: 1-3 days preoperative, postoperative (before the chemotherapy), after 3 chemotherapy cycles, and after 6 chemotherapy cycles. The percentages of the CD3⁺, CD4⁺, CD8⁺, CD45RA⁺, and CD45RO⁺ T cells were measured using flow cytometry. Another 200 healthy women were used as control.

Patients with stage II/III breast cancer had significantly lower percentages of CD3⁺, CD4⁺, CD8⁺, CD45RA⁺, and CD28⁺ T cells in comparison with normal control and those with stage I breast cancer (P < 0.05). The percentages of CD45RO⁺ T cells and CD4⁺CD25⁺ (Treg) cells were significantly higher in stage II/III malignancies versus stage I, and was significantly higher in stage I malignancies versus the normal control (P < 0.05). Breast cancer patients had significantly lower percentages of CD3⁺ and CD4⁺ T cells in comparison with the normal control (P < 0.05). The preoperative percentages of CD3⁺ and CD4⁺ T cells were significantly reduced after 3 cycles and after 6 cycles of chemotherapy (P < 0.05). In patients with stage II/III malignancies, there was a higher percentage of CD45RO⁺ T cells than CD45RA⁺ T cells, which was reversed after surgery. After 6 chemotherapy cycles, the percentage of Treg cells was significantly reduced in comparison with that before the chemotherapy in the patients with stage II/III malignancies.

Patients with breast cancer had significantly suppressed immune functions. Surgical removal of the tumor may improve the immune functions. Chemotherapy significantly reduced the percentages of CD3⁺ and CD4⁺ T cells.