A codelivery system loaded with PDL1-siRNA and sorafenib enhances the therapeutic effect of sorafenib on hepatocellular carcinoma via TAT-poly-SS-lysine modified chitosan.

Sorafenib (SF) is a first-line drug for the treatment of hepatocellular carcinoma (HCC) in clinical practice. However, acquired drug resistance tremendously limits the clinical efficacy of sorafenib in treating HCC, which has attracted great attention. PDL1 plays a crucial role in the drug resistance of HCC. Here, a codelivery system based on poly-SS-lysine modified chitosan (TAT-C-SS-P) was established and was applied to deliver sorafenib and PDL1-siRNA for synergetic HCC therapy. The successful synthesis of TAT-C-SS-P was confirmed by 1H NMR. Additionally, sorafenib and PDL1-siRNA were successfully transported into the cells as the decreased expression of VEGF and PD-L1 by administrated with TAT-C-SS-P@SF@ PDL1-siRNA. Simultaneously, the expression of pro-apoptosis proteins cyt-c and Bax was prominently augmented, whereas the expression of anti-apoptosis protein Bcl-2 was decreased. The reduced expression of PDL1 resulted in the downregulation of P-GP and MRP1, which contributed to more sorafenib aggregation in tumor cells. Moreover, TAT-C-SS-P@PDL1-siRNA@SF efficiently promotes apoptosis of HepG2-SI cells, as the apoptosis rate rised to 73 %. A sorafenib-insensitive model was established to evaluate in vivo antitumor effect of TAT-C-SS-P@PDL1-siRNA@SF. TAT-C-SS-P@PDL1-siRNA@SF showed a tumor inhibition rate of 90.2 ± 3.5 % and no significant decrease in body weight. Taken together, our study provided compelling evidence that TAT-C-SS-P@PDL1-siRNA@SF has great potential application in the treatment of HCC clinically.

Catalpol induces apoptosis in breast cancer in vitro and in vivo: Involvement of mitochondria apoptosis pathway and post-translational modifications.

Breast cancer is a fatal cancer with the highest mortality in female. New strategies for anti-breast cancer are still urgently needed. Catalpol, an iridoid glycoside extracted from the traditional Chinese medicinal plant Rehmannia glutinosa, has shown anticancer efficacy in various cancer cells. However, its effect on breast cancer remains unclear. In this study, we aim to investigate the anti-breast cancer activity of catalpol and elucidate its underlying mechanism. Cell counting kit-8 (CCK-8) and morphology change showed that catalpol could inhibit the proliferation and viability of MCF-7 cells. Catalpol administration reduced the tumor volume in xenograft model. Catalpol induced apoptosis in MCF-7 cells confirmed by Hoechst 33342 staining and Annexin V-FITC/PI double staining. In vivo, catalpol also induced apoptosis as seen from the increased level of terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) in tumor. According to JC-1 and Dichlorodi-hydrofluorescein Diacetate (DCFH-DA) staining, loss of mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) generation was found in MCF-7 cells treated with catalpol. Furthermore, catalpol also increased the level of cytoplasmic cytochrome c and activity of caspase-3 in MCF-7 cells. Likewise, histopathological and immunohistochemical (IHC) assay also found that catalpol enhanced the levels of cytochrome c and caspase-3 in breast cancer tissues. Ultimately, acetylation, 2-hydroxyisobutyrylation and lactylation were dramatically increased, whereas succinylation, malonylation and phosphorylation were markedly decreased in the breast cancer tumor treated with catalpol. Taken together, catalpol inhibited breast cancer in vitro and in vivo through induction of apoptosis via mitochondria apoptosis pathway and regulation of protein post-translational modifications (PTMs). Thus, it can be considered as an excellent candidate compound for treatment of breast cancer.