Thematic Issue: Immuno-Oncology and Immunotherapy

Molecular Mechanisms and Function of the p53 Protein Family Member - p73

Over 20 years after identification of p53 and its crucial function in cancer progression, two members of the same protein family were identified, namely p63 and p73. Since then, a body of information has been accumulated on each of these genes and their interrelations. Biological role of p73 has been elucidated thanks to four distinct knockout mice models: (i) with deletion of the entire TP73 gene, (ii) with deletion of exons encoding the full length TAp73 isoforms, (iii) with deletions of exons encoding the shorter DNp73 isoform, and (iv) with deletion of exons encoding C-terminal of the alpha isoform. This work, as well as expression studies in cancer and overwhelming body of molecular studies, allowed establishing major role of TP73 both in cancer and in neuro-development, as well as ciliogenesis, and metabolism. Here, we recapitulate the major milestones of this endeavor.

Gehua Jiecheng Decoction Inhibits Diethylnitrosamine-Induced Hepatocellular Carcinoma in Mice by Improving Tumor Immunosuppression Microenvironment

Gehua Jiecheng Decoction (GHJCD), a famous traditional Chinese medicine, has been used in the prevention and treatment of precancerous lesion of liver cancer, but its active mechanism has not been reported. This study aimed to evaluate the therapeutic effect of GHJCD on diethylnitrosamine (DEN)-induced hepatocellular carcinoma (HCC) in mice and the mechanism of this effect. We found that GHJCD effectively inhibited the occurrence of liver cancer and reduced the tumor area. The ratio of regulatory cells (Tregs), tumor-associated macrophages (TAMs), and myeloid-derived suppressor cells (MDSCs) in HCC microenvironment was down-regulated, whereas that of CD8 T and effective CD8 T cells was up-regulated. In addition, the expression levels of inflammatory factors IL-6, IL-10, TNF-α, and CCL-2 in the liver were inhibited, whereas those of the angiogenesis related molecules CD31 and VEGF were decreased. Moreover, WNT1, β-catenin, NF-kB, p-MAPK, p-AKT, and p-SRC content in the liver decreased, whereas APC content increased. These results suggested that GHJCD exerted a good inhibitory effect on liver cancer induced by DEN and thus may have a multi-target effect; GHJCD not only antagonized the immunosuppressive effect of the microenvironment of liver cancer but also exerted strong anti-inflammatory and antiangiogenesis effects.