Effect and mechanism of Stellettin B induced human glioblastoma SF295 cells autophagy / 国际生物医学工程杂志

Objective To study the autophagy of human glioblastoma SF295 cells induced by sponge-derived triterpenoid Stellittin B (Stel B) and to discuss the related mechanism. Methods The proliferation inhibitory activity of Stel B on SF295 cells was studied by WST-8 assay. The autophagy effect induced by Stel B on SF295 cells was evaluated bya variety of experimental techniques, including MDC staining, Western Blot assay, and mRFP-GFP-LC3 plasmid transfection method.The activity of Stel B on the representative signal proteins in PI3K/Akt/mTOR pathway in SF295 cells was examined by Western Blot. The anti-tumor activity of Stel B was detected by WST-8 assay after blocking autophagy by autophagy inhibitor chloroquine. Results Stel B could significantly inhibit the proliferation of SF295 cells with IC50 value as 0.026 μmol/L. Plenty of autophagosome was found in Stel B treated A549 cells by MDC staining. The expression of autophagy marker proteins including LC3B-II increased. The confocal microscopy results showed that Stel B promoted autophagosome forming and inhibitedthe fusion of autophagosome with lysosome. The Western Blot results showed that Stel B inhibited the expression of PI3K-p110 protein in SF295 cells and decreased the phosphorylation level of Akt and mTOR.The inhibitory effects of Stel B with different concentrations on SF295 cells were all enhanced by the inhibition of autophagy with chloroquine, and the differences were statistically significant (all P<0.05). Conclusion Stel B can induce SF295 cells autophagy via blocking PI3K/Akt/mTOR pathway. This autophagy effect is beneficial to the survival of SF295 cells. The antitumor activity of Stel B can be enhanced by a combination of autophagy inhibitors.

Class I phosphatidylinositol 3-kinase inhibitors for cancer therapy

The phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in human cancers. Class I PI3Ks are lipid kinases that phosphorylate phosphatidylinositol 4,5-bisphosphate (PIP2) at the 3-OH of the inositol ring to generate phosphatidylinositol 3,4,5-trisphosphate (PIP3), which in turn activates Akt and the downstream effectors like mammalian target of rapamycin (mTOR) to play key roles in carcinogenesis. Therefore, PI3K has become an important anticancer drug target, and currently there is very high interest in the pharmaceutical development of PI3K inhibitors. Idelalisib has been approved in USA and Europe as the first-in-class PI3K inhibitor for cancer therapy. Dozens of other PI3K inhibitors including BKM120 and ZSTK474 are being evaluated in clinical trials. Multifaceted studies on these PI3K inhibitors are being performed, such as single and combinational efficacy, resistance, biomarkers, etc. This review provides an introduction to PI3K and summarizes key advances in the development of PI3K inhibitors.

The practice of multidisciplinary team model in cancer diagnosis and treatment in the primary hospitals / 中华普通外科杂志

Objective To introduce and analyze the status of tumor multidisciplinary team (MDT) model application in primary hospitals.Methods MDT discussion decision-making and implementation of Nanpi People's Hospital from June 2013 to July 2015 were retrospectively analyzed.Results A total of 251 cases were recruited into the MDT discussion.Among them,233 primarily diagnosed cases reached MDT decision-making and 159 cases took the decision,118 cases achieved the purpose (74.2％),41 cases failed (25.8％).Yet in 74 cases not following the decision,11 cases achieved the desired purpose (14.9％),while 63 cases didn't meet the desired purpose (85.1％),the difference was statistically significant (x2 =71.97,P ＜ 0.01).Ultrasound interventional biopsy,enhanced CT scan,CT guided puncture,intraoperative frozen section examination in malignant tumor patients had significantly increased after MDT applied,the difference was statistically significant (all P ＜ 0.05).The annual new rural cooperative medical system referral rate in malignant tumor patients dropped sharply (x2 =19.86,P ＜ 0.01) Conclusions Doctors and cancer patients can benefit from MDT diagnosis and treatment model,which is worth generalization.

Research progress in erythropoietin mimetic peptides / 天津医药

Erythropoietin (EPO) is an active glycoprotein synthesized by kidney. The physiological function of regulat?ing the synthesis of erythrocytes by EPO makes it as a clinical drug for treatment of anemia resulted from chronic kidney fail?ure. However, its short biological half-life makes frequent administration, which limits its wide clinical utility since the tough burden and pain on patients. Therefore, the development of EPO derivatives with good efficacy, less adverse reaction and long duration has been a hot spot in the field during several decades. There are currently many different variants of EPO derivatives including erythropoiesis stimulating agents (ESAs) on the market. This article aims to summarize the recent re?search progress in the development of erythropoietin derivatives, specially focusing on EPO mimetic peptides (EMP).