Rôle de la protéine de stress p8 dans la progression tumorale et le développement des métastases

HSPB8 facilitates prostate cancer progression via activating the JAK/STAT3 signaling pathway

Prostate cancer (PC) is a clinically and biologically heterogeneous disease that lacks effective treatment. Heat shock protein B8 (HSPB8) is an important factor in the progression of various types of cancer. However, the clinical significance and biological role of HSPB8 in PC are still unclear. In this study, we determined HSPB8 expression in PC tissues by immunohistochemical staining and explored the in vitro functions of HSPB8 using HSPB8 knockdown DU145 and LNcap PC cell lines. The in vivo effect of HSPB8 was explored by a subcutaneous xenograft mice model. The human phospho-kinase array and signal transducer and activator of transcription (STAT) 3 activator were utilized to explore the potential mechanism of HSPB8-induced PC progression. As a result, we found that HSPB8 was abundantly expressed in PC tissues and cell lines. HSPB8 knockdown inhibited cell proliferation and migration, promoted apoptosis and cycle repression, as well as weakened tumorigenesis ability. Mechanistically, we demonstrated that HSPB8 facilitates the malignant phenotypes of PC by activating the Janus kinase/STAT3 signaling pathway. These results proposed that HSPB8 seems to be an attractive therapeutic target for PC patients.

p8 Deficiency causes siderosis in spleens and lymphocyte apoptosis in acute pancreatitis

OBJECTIVES

The gene p8 was initially described in pancreatic tissue during acute experimental pancreatitis, a disease that is characterized by a systemic immune response. Although early reports suggested that p8 affects leukocyte migration during acute pancreatitis (AP), no studies revealing its immune-modulatory effects have been performed.

METHODS

We investigated the composition of the cellular immune system in naive p8 knockout (p8(−/−)) mice and compared with matched wild-type mice during pancreatitis.

RESULTS

In young mice, there were no relevant differences in the composition of peripheral and splenic CD3(+), CD3(+)CD4(+), CD3(+)CD8(+), CD11b(+)Gr-1(-), and Gr-1 cells. In mature p8(−/−) mice, increased splenic CD4CD25FoxP3 cells, spleen siderosis, and increased marginal zones in the splenic white pulp were found. During AP, peripheral and splenic CD3(+) and CD3CD4 declined stronger in the p8(−/−) mice. The spleen of the p8(−/−) mice showed severe hypoplasia of the white pulp and mild hyperplasia of the red pulp. This was associated with a significantly increased rate of apoptosis.

CONCLUSIONS

We conclude that p8 has no impact on the cellular composition of the adaptive and innate immune systems in noninflammatory conditions. However, it may limit apoptosis and maintain homeostasis of the immune reaction during AP.