High resolution melting analysis for detecting of JAK2V617F mutation in patients with myeloproliferative neoplasms / 中国实验血液学杂志

This study was purposed to investigate the feasibility of high resolution melting (HRM) in the detection of JAK2V617F mutation in patients with myeloproliferative neoplasm (MPN). The 29 marrow samples randomly selected from patients with clinically diagnosed MPN from January 2008 to January 2011 were detected by HRM method. The results of HRM analysis were compared with that detected by allele specific polymerase chain reaction (AS-PCR) and DNA direct sequencing. The results showed that the JAK2V617F mutations were detected in 11 (37.9%, 11/29) cases by HRM, and its comparability with the direct sequencing result was 100%. While the consistency of AS-PCR with the direct sequencing was moderate (Kappa = 0.179, P = 0.316). It is concluded that the HRM analysis may be an optimal method for clinical screening of JAK2V617F mutation due to its simplicity and promptness with a high specificity.

Molecular mechanism of indirubin-3'-monoxime and Matrine in the reversal of paclitaxel resistance in NCI-H520/TAX25 cell line / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Multidrug resistance (MDR) is a main reason for paclitaxel (TAX) treatment failure. Indirubin-3'-monoxime (IRO) and Matrine are traditional Chinese medicines, which may reverse the resistance of tumor cells to some chemotherapy drugs, but the relationship between paclitaxel resistance and Matrine is still unclear. The aim of this study was to explore the potential molecular mechanism of IRO and Matrine in reversal of TAX resistance.</p><p><b>METHODS</b>In this study, MTT assay was used to measure the non-cytotoxic dosage of IRO and Matrine on NCI-H520/TAX25 cells and determine the reversal extent of TAX resistance under non-toxic doses. In addition, RT-PCR and Western blotting were used to evaluate the mRNA expression and the protein level of survivin, Oct-4, and Sox-2 in NCI-H520/TAX25 cells using semi-quantitative methods.</p><p><b>RESULTS</b>There was no obvious inhibition on sensitive cell strains and drug-resistant strains, when the final concentration was at lest 4 µmol/L for IRO and 100 µmol/L for Matrine. So 4 µmol/L of IRO and 100 µmol/L of Matrine were considered as the reversal dosage. When 4 µmol/L of IRO or 100 µmol/L of Matrine were used together with TAX, the sensitivity to TAX increased evidently in NCI-H520/TAX2 cells; the reversal rate of IRO and Matrine was about 1.92 (43.56/22.6 nmol/L) and 1.74 (43.56/25.0 nmol/L), respectively. The mRNA expression and the protein level of survivin, Oct-4, and Sox-2 in NCI-H520/TAX25 decreased significantly (P < 0.05) after addition of IRO or Matrine in TAX treatment, compared to that of TAX treatment alone.</p><p><b>CONCLUSION</b>The decrease in both mRNA expression and protein level of survivin, Oct-4, and Sox-2 might be the molecular mechanism, by which IRO and Matrine mediate the reversal of TAX resistance.</p>

Effects of 5-Aza-dC on 5-Fu chemosensitivity by modulating TIP30 gene expression in human colorectal cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the effect of 5-Aza-2'-deoxycytidine (5-Aza-dC) on TIP30 gene expression and the relationship between TIP30 expression and the sensitivity to 5-fluouracil (5-Fu) in colorectal cancer cells.</p><p><b>METHODS</b>The methylation profile of TIP30 gene in HCT116 colorectal cancer cells was determined by methylation-specific PCR. The levels of TIP30 mRNA and protein were determined by RT-PCR and Western blot after the 5-Aza-dC treatment. MTT assay was used to detect the chemosensitivity of HCT116 cells to 5-Fu.</p><p><b>RESULTS</b>TIP30 gene displayed complete DNA methylation in the HCT116 cells without 5-Aza-dC pretreatment. After the 5-Aza-dC treatment for 3 days, only demethylating PCR amplification product was detected and TIP30 gene showed DNA demethylation. With the prolongation of the time of removal of 5-Aza-dC treatment, methylated and demethylated PCR amplification products were observed and TIP30 gene displayed both DNA methylation and DNA demethylation in the colorectal cancer cells. At the day 10 after removal of 5-Aza-dC, methylating PCR amplification product appeared and TIP30 gene showed DNA methylation. No expressions of TIP30 mRNA and protein were detected in the HCT116 cells untreated with 5-Aza-dC. After the treatment of 5-Aza-dC for 3 d and then removed the 5-Aza-dC, the expressions of TIP30 mRNA and protein were increased obviously. With the prolonged time after 5-Aza-dC removal, the expressions of TIP30 mRNA and protein decreased and reached the lowest level on day 10. The IC50 values of 5-Fu were 41.62, 33.17 and 4.96 µg/ml in the HCT116 cells pretreated with 5-Aza-dC, d0 and d10 with the drug removal after drug treatment for 3 d, respectively.</p><p><b>CONCLUSIONS</b>The results of this study show that the expression of TIP30 gene may be associated with its DNA methylation status and may affect the sensitivity of colorectal cancer cells to 5-Fu.</p>

NNIspm, a polyamine derivative, induces cellular senescence of human hepatoma HepG2 cells and its molecular mechanism / 药学学报

This study is to examine the effects of NNIspm-mediated cellular senescence of HepG2 cells and elucidate its potential molecular mechanism. Cellular senescence was detected with senescence-associated beta-galactosidase staining. Cell cycle distribution, intracellular fluorescence intensity and accumulation of intracellular reactive oxygen species (ROS) were detected by high content screening (HCS). Protein expression was detected by Western blotting. Polyamines content was analyzed by high performance liquid chromatography (HPLC). The results demonstrated that NNIspm significantly induced HepG2 cells senescence. This effect was due to the decrease of intracellular polyamines, the arrest at G0/G1 phase and an increase of ROS level. The molecular senescence marker p21 increased significantly after NNIspm treatment. In contrast, the protein expressions of Cyclin E and CDK2 were obvious down-regulation. The results indicated that cellular senescence induced by NNIspm was one of its antitumor mechanisms.

Role of the cut-off value of serum neuron-specific enolase in differentiating small cell lung cancer from non-small cell lung cancer / 南方医科大学学报

<p><b>OBJECTIVE</b>To determine the cut-off value of serum neuron-specific enolase (NSE) level for distinguishing small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>Serum NSE levels were measured by enzyme-linked immunosorbent assay in 137 patients with NSCLC or SCLC, and the best cut-off value was analyzed using ROC curve.</p><p><b>RESULTS</b>The positivity rate of serum NSE was significantly higher in patients with SCLC than in those with NSCLC (P<0.01). The best cut-off value was 15.45 microg/L using ROC curve, which gave a sensitivity of 66.7% and specificity of 65.7%.</p><p><b>CONCLUSION</b>Serum NSE level may allow simple and cost-effective differentiation of SCLC and NSCLC.</p>