Cadmium-induced stress: a close look at the relationship between autophagy and apoptosis.

Stress is acknowledged as one of the major factors responsible for autophagy induction, a tightly regulated process that acts as a pro-death or pro-survival mechanism within cells. Cadmium (Cd), a toxic heavy metal, induces apoptosis and autophagy in cells after exposure to low concentrations. This is due to Cd's ability to induce oxidative stress in cells and tissues by overproducing reactive oxygen species. Several proteins have been found to mediate the process of autophagy but aspects of their specific roles and targets remain undefined. Though LC3-II and p62 have traditionally been used as biomarkers that define autophagy, recent findings have revealed some limitations to LC3-II because it can be accumulated in cells in an autophagy-independent manner, whereas p62 remains a good determinant of the process. In addition to LC3-II and p62, recent studies have suggested that a new member of the autophagy protein family, the vacuole membrane protein 1 (VMP1), is essential in driving autophagy and could be an important biomarker for detecting the initiation and progression of autophagy. This review therefore focuses on current trends in autophagy biomarkers, the effect of Cd on the expression of LC3-II, p62, VMP1, and Beclin-1 and their relation and inter-regulatory roles in autophagy and apoptosis, pharmacological importance, and the mechanisms involved.

Multifunctional elastin-like polypeptide renders ß-glucosidase enzyme phase transition and high stability.

BACKGROUND: In the enzymatic conversion of biomass, it becomes an important issue to efficiently and cost-effectively degrade cellulose into fermentable glucose. ß-Glucosidase (Bgluc), an essential member of cellulases, plays a critical role in cellulosic biomass degradation. The difficulty in improving the stability of Bgluc has been a bottleneck in the enzyme-dependent cellulose degradation. The traditional method of protein purification, however, leads to higher production cost and a decrease in activity. To simplify and efficiently purify Bgluc with modified special properties, Bgluc-tagged ELP and His with defined phase transitions was designed to facilitate the process. RESULTS: Here, a novel binary ELP and His tag was fused with Bgluc from termite Coptotermes formosanus to construct a Bgluc-linker-ELP-His recombinant fusion protein (BglucLEH). The recombinant plasmid Bgluc expressing a His tag (BglucH) was also constructed. The BglucLEH and BglucH were expressed in E. coli BL21 and purified using inverse transition cycling (ITC) or Ni-NTA resin. The optimum salt concentration for the ITC purification of BglucLEH was 0.5 M (NH4)2SO4 and the specific activity of BglucLEH purified by ITC was 75.5 U/mg for substrate p-NPG, which was slightly higher than that of BglucLEH purified by Ni-NTA (68.2 U/mg). The recovery rate and purification fold of BglucLEH purified by ITC and Ni-NTA were 77.8%, 79.1% and 12.60, 11.60, respectively. The results indicated that purification with ITC was superior to the traditional Ni-NTA. The K m of BglucLEH and BglucH for p-NPG was 5.27 and 5.73 mM, respectively. The K ca t/K m (14.79 S-1 mM-1) of BglucLEH was higher than that of BglucH (12.10 S-1 mM-1). The effects of ELP tag on the enzyme activity, secondary structure and protein stability were also studied. The results showed that ELP tag did not affect the secondary structure or enzyme activity of Bgluc. More importantly, ELP improved the protein stability in harsh conditions such as heating and exposure to denaturant. CONCLUSION: The Bgluc-linker-ELP-His system shows wide application prospect in maintaining the activity, efficient purification and improving the stability of Bgluc. These properties of BglucLEH make it an interesting tool to reduce cost, to improve the efficiency of biocatalyst and potentially to enhance the degradation of lignocellulosic biomass.

The application of prostate specific membrane antigen in CART­cell therapy for treatment of prostate carcinoma (Review).

Adoptive cell transfer (ACT) is an emerging immunotherapy technique that restricts tumor growth and invasion in cancer patients. Among the different types of ACT, chimeric antigen receptor (CAR)T­cell therapy is considered to be the most advanced and a potentially powerful technique for the treatment of cancer in clinical trials. The primary aim of CART­cell therapy is to destroy cancer cells and therefore, it serves an important role in tumor immunotherapy. CART­cell therapy has been demonstrated to mainly treat blood cancer by targeting cluster of differentiation (CD)­19, CD20, CD22, CD33 and CD123. However, the use of CART­cell therapy for treating solid tumors is currently under extensive investigation. With respect to prostate cancer, prostatic acid phosphatase, prostate­specific antigen, prostate­specific membrane antigen (PSMA), prostate stem cell antigen, T­cell receptor Î³ alternate reading frame protein, transient receptor potential­p8 and six­transmembrane epithelial antigen of the prostate 1 are among the identified target antigens for prostate tumors. However, mesothelin, fibroblast activation protein, epidermal growth factor receptor, carcinoembryonic antigen, disialoganglioside­2 and human epidermal growth factor 2 are among the main targets of CART­cell therapy in the case of other types of solid tumors. The main challenges in CART­cell therapy are the selection of the target antigens and the modulation of the ideal tumor microenvironment for T­cells to fight against the cancer. The present review focuses on the 1st, 2nd, 3rd and 4th generations of anti­PSMA CARs and their application for combating prostate carcinoma.