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Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Angiogenesis is reported to play a pivotal role in the occurrence, development and metastasis of HCC. The renin-angiotensin system (RAS) is involved in the regulation of angiogenesis. Here, based on the analysis of HCC datasets from Gene Expression Omnibus (GEO) database and The Cancer Genome Atlas (TCGA), we found that there was a negative correlation between the mRNA levels of angiotensin converting enzyme 2 (ACE2) and CD34. To explore the association of RAS with the progression from fibrosis to cirrhosis to HCC, liver specimens and serum samples were collected from patients with hepatic fibrosis, cirrhosis and HCC. Relative hepatic mRNA levels of CD34 and ACE2 were determined by real-time PCR, and the serum concentrations of Angiotensin II (Ang II), Ang (1-7) and vascular endothelial growth factor (VEGF) were detected by ELISA. We found that ACE2 mRNA was gradually decreased, while CD34 mRNA was progressively increased with the increasing grade of disease severity. Concentrations of Ang II, Ang (1-7) and VEGF were higher in the sera of patients than in that of healthy volunteers. These proteins' concentrations were also progressively increased with the increasing grade of disease severity. Moreover, a positive correlation was found between VEGF and Ang II or Ang (1-7), while negative correlation was observed between mRNA levels of CD34 and ACE2. More importantly, patients with higher level of ACE2 expression had longer survival time than those with lower level of ACE2 expression. Taken together, our data suggests that the low expression of ACE2 may be a useful indicator of poor prognosis in HCC. The RAS may have a role in the progression of HCC., (Copyright © 2015 Elsevier Inc. All rights reserved.)

An accurate and validated liquid chromatography method and a triple quadrupole mass spectrometry method were developed and validated to simultaneously evaluate the cytochrome P450 (CYP) enzymes in vivo using the co-administration of these probes. Phenacetin, losartan, metoprolol and midazolam were used as the probe substrates for rat CYP1A2, CYP2C11, CYP2D4 and CYP3A1 enzymes, respectively. The purpose of the study was to investigate the effect of apatinib on these cytochrome P450 enzymes in vivo with co-administration of these probes. Plasma samples were prepared by precipitating protein with acetonitrile. The analytes were separated using a reversed-phase BEH C18 column (2.1mm×100mm, 1.7μm, Waters, USA) maintained at 40°C. The mobile phase consisted of acetonitrile and water (containing 0.1% formic acid) with a gradient elution pumped at a flow rate of 0.4mL/min. The analytes were detected with positive electrospray ionization in multiple reaction monitoring (MRM) mode for target fragment ions m/z 180.05→109.94 for phenacetin, m/z 423.1→207.2 for losartan, m/z 268.12→115.8 for metoprolol, m/z 326.02→290.99 for midazolam and m/z 285.1→193.1 for diazepam (IS). Good linearity was achieved to quantify the concentration ranges of 10-2000ng/mL for phenacetin, 10-1000ng/mL for losartan, 10-1000ng/mL for metoprolol and 1-100ng/mL for midazolam in rat plasma. The mean recoveries of phenacetin, losartan, midazolam and metoprolol from the plasma exceeded 77.07%. The intra-run and inter-run assay precisions were both less than 8.9%. This method was successfully applied to evaluate the effects of apatinib on the cytochrome P450 enzymes in rats., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Using a proteomic approach, we have previously shown that exposure to different concentrations of cisplatin during a 12-h period can lead to changes in nuclear protein expression and alternative splicing in HeLa cells. To further shed light on the DNA damage response (DDR) induced by cisplatin, we examined the nuclear proteome profiles of HeLa cells treated with 5μM cisplatin for different times (2, 12, and 24h). Two-dimensional electrophoresis (2-DE) identified 98 differentially expressed proteins in cisplatin-treated cells as compared to control cells. Among them, 54 spots (55%) were down-regulated and 44 spots (45%) were up-regulated. 51 spots were subjected to Matrix-assisted-laser-desorption-ionization Time-of-flight/time-of-flight Mass spectrometry (MALDI-TOF/TOF MS) identification, and 40 spots were identified. Among these, 22 proteins were located in nucleus. These proteins were involved in stress response, cell cycle and division, apoptosis, mRNA processing, transport, splicing and microRNA (miRNA) maturation. The changed expression of Annexin A1 and Lamin B1 were confirmed by Western blot. The role of Annexin A1 in the response to cisplatin-induced DNA damage was further analyzed, and it was shown that after Annexin A1 knockdown, cisplatin-induced DNA damage was significantly increased. In addition, the changed expression of several miRNAs was also observed by quantitative real-time PCR (qRT-PCR). Taken together, these data indicate that cisplatin-induced DDR is a complex process, and that those proteins identified by proteomics can lead to new directions for a better understanding of this process., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Cisplatin has been widely accepted as one of the most efficient anticancer drugs for decades. However, the mechanisms for the cytotoxic effects of cisplatin are still not fully understood. Cisplatin primarily targets DNA, resulting in the formation of DNA double strand breaks and eventually causing cell death. In this study, we applied two-dimensional electrophoresis coupled with LC-MS/MS to analyze the nuclear proteome of HeLa cells treated with cisplatin, in an effort to uncover new mechanistic clues regarding the cellular response to cisplatin. A total of 19 proteins were successfully identified, and these proteins are involved in a variety of basal metabolic and biological processes in cells, including biosynthesis, cell cycle, glycolysis and apoptosis. Six were related to the regulation of mRNA splicing, and we therefore asked whether the Fas gene might undergo alternative splicing following cisplatin treatment. This proved to be the case, as the splicing forms of Fas were modified in cisplatin-treated HeLa cells. This work provides novel information, from the perspective of the nuclear response, for understanding the cytotoxicity caused by cisplatin-induced DNA damage., (Copyright © 2010 Elsevier B.V. All rights reserved.)