Immunotherapy for gastric cancer: dilemmas and prospect.

Gastric cancer remains the second most common cause of cancer-related death worldwide. Because of the poor prognosis of late-stage gastric cancer patients, it is imperative to develop new strategies to improve the survival rate of this disease. Currently, immunotherapy is considered as an innovative approach for cancers such as lung cancer, gastric cancer and breast cancer. In fact, previous works have revealed promising results in this field. With further understanding of immunogenomics of gastric cancer, new immune checkpoint regulators could become more important. In addition, whole-genome sequencing and genome editing provide us with more information on the heterogeneity of gastric cancer, showing helpful tools to identify new predictive biomarkers and to achieve personalized treatment. Further research and better understanding of the functions of immune system will enhance immunotherapy treatment in the future.

Upregulation of human leukocyte antigen-G expression and its clinical significance in ductal breast cancer.

Human leukocyte antigen(HLA)-G could inhibit functions of immune cells and induce regulatory T cells (Treg) and could be involved in antitumor immune responses. In the current study, HLA-G expression in 58 primary breast cancer lesions was analyzed with immunohistochemistry. Plasma soluble HLA-G was detected with enzyme-linked immunosorbent assay in 92 breast cancer patients and in 70 normal healthy donors. The proportion of CD4(+)CD25(+)FoxP3(+) Treg was analyzed with flow cytometry in 64 breast cancer patients and 23 normal controls. HLA-G expression was observed in 70.7% (41/58) of breast cancer lesions. Lesion HLA-G expression was more frequently observed in advanced disease stage (I/II vs III/IV, p = 0.044) and tumor grade (I/II vs III/IV, p = 0.021). sHLA-G was dramatically increased in patients when compared with normal controls (median 82.19 vs 9.65 U/ml, p < 0.001); The area under the receiver operating characteristic (ROC) curve for sHLA-G was 0.953 (95% confidence interval [CI] = 0.926-0.981, p < 0.001). However, sHLA-G was irrelevant to the disease stage and tumor grade. Moreover, CD4(+)CD25(+)FoxP3(+) Treg are markedly increased in the breast cancer patients compared with normal controls (4.46+/-1.36% vs 2.67+/-1.45%, p < 0.001), and the increased frequency of Treg was strongly correlated to sHLA-G levels (R = 0.582, p = 0.001). Our findings indicated that HLA-G could play critical roles in the progression of breast cancer, and plasma sHLA-G levels might be a useful preoperative biomarker for diagnosis.