Autophagy protein p62/SQSTM1 is involved in HAMLET-induced cell death by modulating apotosis in U87MG cells.

HAMLET is a complex of oleic acids and decalcified α-lactalbumin that was discovered to selectively kill tumor cells both in vitro and in vivo. Autophagy is an important cellular process involved in drug-induced cell death of glioma cells. We treated U87MG human glioma cells with HAMLET and found that the cell viability was significantly decreased and accompanied with the activation of autophagy. Interestingly, we observed an increase in p62/SQSTM1, an important substrate of autophagosome enzymes, at the protein level upon HAMLET treatment for short periods. To better understand the functionality of autophagy and p62/SQSTM1 in HAMLET-induced cell death, we modulated the level of autophagy or p62/SQSTM1 with biochemical or genetic methods. The results showed that inhibition of autophagy aggravated HAMLET-induced cell death, whereas activation of authophagy attenuated this process. Meanwhile, we found that overexpression of wild-type p62/SQSTM1 was able to activate caspase-8, and then promote HAMLET-induced apoptosis, whereas knockdown of p62/SQSTM1 manifested the opposite effect. We further demonstrated that the function of p62/SQSTM1 following HAMLET treatment required its C-terminus UBA domain. Our results indicated that in addition to being a marker of autophagy activation in HAMLET-treated glioma cells, p62/SQSTM1 could also function as an important mediator for the activation of caspase-8-dependent cell death.

Celastrol enhances AAV1-mediated gene expression in mice adipose tissues.

The transduction of adeno-associated virus (AAV) in adipose tissues was not well characterized and appeared to be insufficient as compared with other targeted tissues in gene therapy. We have found that celastrol, a chemical from a traditional Chinese herb known to inhibit the proteasome activity, was able to enhance the transgene expression mediated by AAV1 in 3T3-L1 preadipocytes both before and after induced differentiation. A synergism of celastrol and nonionic surfactant pluronic F68 cotreatment on AAV1 transduction was observed in the experiments with rat primary preadipocyte cultures and in adipose tissues in vivo. By fluorescent microscopy using Alexa Fluor 647-labeled AAV and quantitative PCR assays, we found that celastrol treatments increased the nuclear distribution of AAV genomic DNAs, but not the total amount of viral cellular uptake in preadipocytes, which was different from the effect of pluronic F68 treatment to significantly promote the AAV internalization. Our data suggested that bioactive monomeric compounds extracted from herbal medicines might be used to facilitate AAV-mediated gene transfer applications.

Enhanced efficacy in anti-tumour activity by combined therapy of recombinant FGFR-1 related angiogenesis and low-dose cytotoxic agent.

Fibroblast growth factor receptor-1 (FGFR-1) has been used as a target for anti-angiogeneic therapy of cancer. The strategies of combining anti-angiogenic biotherapy with chemotherapeutic drugs show potential and promise for cancer therapy. In this study, we evaluated the anti-tumour efficacy of chicken FGFR-1 (cFR-1) vaccine combined with low-dose gemcitabine in two mice tumour models. We found that both the cFR-1 vaccine and low-dose gemcitabine can suppress tumour growth to some extent. Remarkably, the combination strategy produces an apparent decrease in tumour volume, microvessel density and tumour cell proliferation, and an increase of apoptosis without obvious side-effects compared with either therapy alone. Moreover, the combination strategy also demonstrated synergistic indices against tumour growth and angiogenesis. Furthermore, auto-antibodies against mouse FGFR-1 were identified. These findings support the idea that the combination strategy synergistically strengthens anti-tumour activity via suppression of tumour angiogenesis without overt toxicity in tumour-bearing mice.

An economic analysis of biomass gasification and power generation in China.

With vast territory and abundant biomass resources China appears to have suitable conditions to develop biomass utilization technologies. As an important decentralized power technology, biomass gasification and power generation (BGPG) has a potential market in making use of biomass wastes. In spite of the relatively high cost for controlling secondary pollution by wastewater, BGPG is economically feasible and can give a financial return owing to the low price of biomass wastes and insufficient power supply at present in some regions of China. In this work, experimental data from 1 MW-scale circulating fluidized bed (CFB) BGPG plants constructed recently in China were analyzed; and it was found that the unit capital cost of BGPG is only 60-70% of coal power station and its operation cost is much lower than that of conventional power plants. However, due to the relatively low efficiency of small-scale plant, the current BGPG technology will lose its economic attraction when its capacity is smaller than 160 kW or the price of biomass is higher than 200 Yuan RMB/ton. The development of medium-scale BGPG plants, with capacity ranging from 1000 to 5000 kW, is recommended; as is the demonstration of BGPG technology in suitable enterprises (e.g. rice mill and timber mill) in developing countries where large amounts of biomass wastes are available so that biomass collection and transportation can be avoided and the operation cost can be lowered.

[Research on the selecting suspension cell line of higher productivity of flavonol glycoside by hypoxia stress as well as the stability in subcultures].

Investigate the influence of culture media to growth and flavonol glycoside synthesis of calli introduced from seedling of Ginkgo biloba. 6 cell lines were selected from calli by hypoxia stress. Among these cell lines the best one TZ-1 which growth index was 4.12 and the flavonol glycoside content was 1.25% in dried cell which was enhanced 257.1% compared with callus. The stability in subcultures was investigated: The average content of flavonol glycoside was 1.25% in dried cells and the growth index was 3.99 during 6 subcultures. Which variation coefficient was separately 0.065 and 0.048. The results show that hypoxia stress is a efficient method to select suspension cell line of higher productivity of flavonol glycoside.

Four geographically distinct genotypes of JC virus are prevalent in China and Mongolia: implications for the racial composition of modern China.

JC polyomavirus (JCV) is ubiquitous in humans, persisting in renal tissue and excreting progeny in urine. It has been shown that the genotyping of urinary JCV offers a novel means of tracing human migrations. This approach was used to elucidate the racial composition of modern China. JCV isolates in the Old World were previously classified into nine distinct genotypes. One of them (B1) has a wide domain, encompassing part of Europe and the entirety of Asia. By constructing a neighbour-joining phylogenetic tree, all B1 isolates detected so far were classified into four distinct groups (B1-a to -d), each occupying unique domains in the world. According to this revised classification system of JCV DNAs, four genotypes (CY, SC, B1-a and -b) were found to be prevalent in China and Mongolia (Mongolia was studied instead of Inner Mongolia, which is part of China). There was a remarkable variation in the incidence of genotypes among the sites of sample collection. CY was more frequently detected in Northern China, SC was predominant in Southern China and B1-b was detected only in Mongolia. B1-a was spread throughout China. These data were statistically analysed and the observed regional differences in the incidence of genotypes were found to be significant. It is likely that these differences in JCV distribution in China reflect the intermingling of different population groups that constitute modern China.