IL-6 mediated JAK/STAT3 signaling pathway in cancer patients with cachexia.

OBJECTIVES: We investigated the changes in the IL-6 and STAT3 expression levels in cachectic and non-cachectic patients with gastric, lung and breast cancer and evaluated the association between IL-6 and STAT3 levels and cancer types in terms of cachexia condition. BACKGROUND: Cancer-associated cachexia, observed in nearly 50‒80 % of cancer patients, has drawn attention in advanced patients. IL-6/JAK/STAT pathway plays an essential role in the progression of cancer cachexia through the regulation of the inflammatory response. METHODS: This study consisted of 48 gastric, breast and lung cancer patients (18 cachectic and 30 non-cachectic) and healthy individuals. Total RNA isolation and cDNA synthesis was performed after the collection of blood samples. IL-6 and STAT3 expression levels were analyzed by RT- PCR analysis. RESULTS: Our findings demonstrated that IL-6 mRNA levels considerably increased 19.89±8.25, 5.18±2.81 and 15.33±9.54-fold in gastric, lung and breast cancer patients with cachexia, respectively. Additionally, a 16.67±7.13, 14.21±11.72 and 8.85±3.89-fold increase in the STAT3 expression level was detected in cachectic gastric, lung and breast cancer patients, respectively (p<0.01). CONCLUSION: STAT3 may be considered as a therapeutic target for cachectic patients with gastric, lung and breast cancer. Furthermore, IL-6 mediates STAT3 activation in cachectic gastric and breast cancer patients (Tab. 5, Fig. 2, Ref. 62).

The role of usnic acid-induced apoptosis and autophagy in hepatocellular carcinoma.

Usnic acid (UA) is a multifunctional bioactive lichen secondary metabolite with potential anti-cancer properties. Although the promising therapeutic effects of UA have been investigated in different cancer cell lines, the mechanism driving UA-induced cell death has yet to be elucidated. As the type of cell death (apoptosis or autophagy) induced by UA may vary depending on the cancer cell type, we first studied the cytotoxic effects of UA in HEPG2 (HBV(-)) and SNU-449(HBV(+)) hepatocellular carcinoma (HCC) cell lines. HCC cell viability was considerably reduced in a dose-dependent manner at 12, 24, and 48 h after treatment with UA ( p < 0.05). However, SNU-449 cells were more sensitive to UA than HEPG2 cells. UA also induced apoptotic cell death in HCC cells with cell cycle arrest at G0/G1 and G2/M phase depending on the genetic profile of each cell type. On the other hand, we observed acidic vesicular organelles in HCC cells after 36 h of UA treatment. Taken together, these findings suggest that UA stimulates apoptosis and autophagy in HEPG2 and SNU-449 cells without damaging normal control cells. Thus, UA might be a potential therapeutic compound for HCC treatment. However, there is a need for further studies investigating the death-promoting or preventing roles for autophagy and the molecular signaling mechanisms induced by UA treatment.