Glucans are glucose polymers that constitute a structural part of fungal cell wall. They can stimulate the innate immunity by activation of monocytes/macrophages. In human studies it has been shown that beta glucan has an immunomodulatory effect and can increase the efficacy of the biological therapies in cancer patients. In this prospective clinical trial we assessed in vivo effects of short term oral beta glucan administration on peripheral blood monocytes and their expression of activation markers in patients with advanced breast cancer.

23 female patients with advanced breast cancer were included in the study. Median age of the patients was 52 years. Sixteen healthy females with a median age of 48 years served as the control group for comparing the initial blood samples. Peripheral blood samples were drawn on day zero and patients started receiving oral 1–3, 1–6, D-beta glucan daily. Blood samples were recollected on the 15th day. In the initial samples mean lymphocyte count was significantly lower in the patients with breast cancer (1281±306/mm³ versus 1930±573/mm³, p=0.04). In the patients with breast cancer, mean monocyte count which was 326+124/mm³ at the beginning, was increased to 496+194/mm³ at the 15th day (p=0.015). Expression of CD95 (Apo1/Fas) on CD14 positive monocytes was 48.17% at the beginning, which was increased to 69.23 % at the 15th day (p=0.002). Expression of CD45RA on CD14 positive monocytes was 49.9% at the beginning; it was increased significantly to 61.52% on day 15 (p=0.001).

Oral beta glucan administration seems to stimulate proliferation and activation of peripheral blood monocytes in vivo in patients with advanced breast cancer.