Immunotherapy and immunoprevention of cancer: where do we stand?

Dendritic cell-based cancer immunotherapy for colorectal cancer

Colorectal cancer (CRC) is one of the most common cancers and a leading cause of cancer-related mortality worldwide. Although systemic therapy is the standard care for patients with recurrent or metastatic CRC, the prognosis is extremely poor. The optimal sequence of therapy remains unknown. Therefore, alternative strategies, such as immunotherapy, are needed for patients with advanced CRC. This review summarizes evidence from dendritic cell-based cancer immunotherapy strategies that are currently in clinical trials. In addition, we discuss the possibility of antitumor immune responses through immunoinhibitory PD-1/PD-L1 pathway blockade in CRC patients.

CCR3, CCR4, CCR5, and CXCR3 expression in peripheral blood CD4+ lymphocytes in gastric cancer patients

Background:

CD4+(TH1, and TH2) cell groups in the point of view of chemokine receptor expression were considered in blood of stomach cancer patients.

Materials and Methods:

The percentage of blood CD4+ T cells expressing chemokine receptors (before and after gastrectomy) was determined by flow cytometry (Becton Dickinson, USA) using the following chemokine receptor antibodies: anti-CCR5, anti-CXCR3, anti-CCR3 and anti-CCR4.

Results:

The means of CD4⁺ CCR5⁺ expressing cells was 1.23% ± 0.90, 0.83% ± 0.34 and 1.34% ± 0.74 in control, pre- and post-operation groups, respectively. CD4⁺ CXCR3⁺ expressing cells were 19.09% ± 8.4, 16.95% ± 5.71 and 25.08% ± 9.31, respectively. Similar pattern was seen for CD4⁺ CCR3⁺ and CD4⁺ CCR4⁺ expressing cells. Pearson correlation analysis shows no relationship between CCR3 and CCR4 expressions on TCD4 cells (r = 0.211, P = 0.126). The complex expression TH1 (CD4⁺ CXCR3⁺ CCR5⁺) receptors determined 1.14% ± 0.54 for control group, 0.86% ± 0.49 for pre-T and 1.57% ± 0.67 for post-T group. Moreover, the TH2 (CD4⁺ CCR3⁺ CCR4⁺) expression was 1.60% ± 1.05 for control group, 1.57% ± 0.83 for pre-T and 1.27% ± 0.66 for post-treatment group. Pearson correlation analysis shows that only the CCR3 and CCR5 expression was statistically correlated (r = 0.321, P = 0.018).

Conclusion:

Due to low expression of CCR5 in TH1 and CCR3 in TH2 cells, it seems that utility of these is extremely limited for clinical evaluation, but not scientific purpose. Moreover, considering the CXCR3 for TH1 cells and CCR4 expression for TH2 cells, due to considerable expression, may be practical.

ErbB2 transgenic mice: a tool for investigation of the immune prevention and treatment of mammary carcinomas

The epidermal growth factor receptor belongs to a superfamily of receptor tyrosine kinases (RTK) that includes ErbB2. ErbB2 is involved in normal physiological processes, such as embryogenesis, cell proliferation, differentiation, adhesion motility, and apoptosis, while its malfunction or overexpression is responsible for development defects, diabetes, and cancer. The human ortholog of ErbB2 is referred as Her-2 (human ErbB2) while the rat ortholog is referred as neu (rat ErbB2). As ErbB2 is directly involved in carcinogenesis, mice transgenic for the rat neu oncogene allow straightforward assessment of the ability of drugs and vaccines to inhibit the progression of neu-driven cancer. Information from this model may provide indications on the efficacy of similar treatments in patients. This commentary provides key information regarding the use of these transgenic mouse models for evaluation of the efficacy of anti-tumor strategies.

Vaccines for tumour prevention

Despite tremendous progress in basic and epidemiological research, effective prevention of most types of cancer is still lacking. Vaccine use in cancer therapy remains a promising but difficult prospect. However, new mouse models that recapitulate significant features of human cancer progression show that vaccines can keep precancerous lesions under control and might eventually be the spearhead of effective and reliable ways to prevent cancer.