The utility of the Ion Torrent PGM next generation sequencing for analysis of the most commonly mutated genes among patients with colorectal cancer in India

Background: The requirement for the mutation analysis for Kirsten rat sarcoma viral oncogene (KRAS) in colorectal cancer (CRC) is rapidly increasing as it is a predictive biomarker and also, its absence signifies response to anti?epidermal growth factor receptor (anti?EGFR) antibody treatment. The aim of our study was to investigate the pathological diagnosis and distribution of KRAS mutations in colorectal cancer with the use of next generation sequencing platform (Ion Torrent). Methods: A total of 56 CRC samples were tested to identify the genetic mutations, especially KRAS using the primers which included ~2800 COSMIC mutations of 50 oncogenes. Ion Torrent personal genome machine (semiconductor?based sequencing) was used for the sequencing and analysis. Along with KRAS, other 49 genes were also studied for COSMIC mutations. Results: KRAS mutation 25 (44.6%) had the highest frequency, followed by TP53 10 (17.9%) and PIK3CA mutation 4 (7.1%). Of all the KRAS mutations identified, mutations in codon 12 were most frequent followed by mutations in codon 13 and 61. The most frequent substitution was glycine to aspartate mutation in codon 12 (p.Gly12Asp) followed by glycine to valine (p.Gly12Val). Combinations of mutations were also studied. Our study revealed that seven cases (12.5%) had both KRAS and TP53 mutations (highest of all the combinations). Conclusion: The analysis of KRAS mutation frequency and its mutational subtype analysis in human CRCs by using semiconductor?based platform in routine clinical practices have been performed in Indian population. The findings were similar to earlier published reports from the Western literature.

Research progress of famesyltransferase and its inhibitors in cancer therapy / 中国药理学通报

Famesyltransferase, a membrane-associated protein, catalyzes the addition of the 15-carbon fragment of famesyl diphosphate to the cysteine SH group of the CAAX motif containing protein substrates to regulate the function of target proteins through famesylation. As one of the most important target proteins of FTase, oncogenic forms of Ras mutants have been reportedly involved in more than 30% human cancers, and are known to play critical roles in cancer development and progression. Despite decades of research, Ras inhibitors are so elusive that no therapeutic agents directly targeting Ras mutants have been clinically approved, the primary reason for which is the lack of druggable pockets on the surface of Ras. Therefore, FTase, the main regulator of Ras protein, has gradually become a research hotspot, and many FTase inhibitors have been developed, synthesized and used for the treatment of malignant tumors. In the present review, we briefly describe the regulation of Ras functions by FTase and the role of FTase in cancers, and mainly explore the research progress of FTase inhibitors as a promising strategy for cancer therapy.

Effects of Zishen Yutai Pills on the expressions of regulatory factors in recurrent spontaneous abortion mice / 中成药

AIM To observe the effect of Zishen Yutai Pills (Cuscutae Semen,Ginseng Radix et Rhizoma,Dipsaci Radix,etc.) on RAS,VEGF,VEGFR-2,sVEGFR-1 and MAPK in recurrent miscarriage mice,and to explore its mechanism.METHODS CBA/J female mice + DBA/2 male mice,and CBA/J female mice + BALB/c male mice were mated by 2 females and 1 male in cage to establish the RSA model and the normal pregnancy CBA × BALB/c mouse model respectively.Since the zeroth day of pregnancy,a total of 24 CBA/J × DBA/2 mice were randomly divided into model control group,Zishen Yutai Pills group and progesterone capsule group,and 10 CBA × BALB/c mice were used as normal pregnancy control group.Mice of all groups after the respective 15-day intervention had their rate of uterine embryo loss measured and calculated.Their pathological changes of decidual tissue were determined by HE staining,their RAS,VEGF,VEGFR-2,sVEGFR-1,MAPK protein and mRNA expressions were detected by immunohistochemistry and real-time PCR.RESULTS Zishen Yutai Pills significantly reduced the rate of embryo loss and improved pathological changes of decidual tissue in RSA mice through regulating mouse decidual tissue angiogenesis and recasting,as revealed by the lowered levels of RAS,VEGF,VEGFR-2 and MAPK,and increased expression of sVEGFR-1.CONCLUSION Zishen Yutai Pills can lower the rate of embryo loss and improve decidual angiogenesis in RSA mice through altering the expression of RAS,VEGF,VEG-FR-2,sVEGFR-1 and MAPK.

Expression of P21ras and PIK3CA in human tissues of hepatocellular carcinoma and hepatic cirrhosis / 国际外科学杂志

Objective To investigate the expression of P21ras and PIK3CA proteins in hepatitis B virus-related hepatocellular carcinoma(HBV-HCC), post-hepatitis B hepatic cirrhosis (HBV-hepatic cirrhosis)and normal hepatic tissues specimen, and their correlation between HBV-HCC and HBV-hepatic cirrhosis tissues.Methods Using immunohistochemistry, the expression of P21ras and PIK3CA proteins in 34 cases of HBV-HCC, 37 cases of HBV-hepatic cirrhosis and 30 cases of normal liver tissues specimen were detected and compared. Results The mean gray scales of P21ras protein in HBV-HCC, HBV-hepatic cirrhosis and normal hepatic tissue specimen were 138.86 ± 2.9, 145. 34 ± 2.06 and 152.07 ± 1.17 (P ＜ 0. 0l), respectively, and were related to the progression of hepatopathy (P ＜0.01). The mean gray scales of PIK3CA protein in HBV-HCC, HBV-hepatic cirrhosis and normal hepatic tissue specimen were 138.20 ± 3. 14, 149.49 ±0. 78 and 154.71 ± 1.29 (P ＜ 0.01), respectively, and were related to the progression of hepatopathy (P ＜ 0. 01).There were apparent correlation between P21ras and PIK3CA in HBV-HCC and HBV-hepatic cirrhosis respectively (r =0. 64, P ＜0. 05; r =0. 42, P ＜0. 05). Conclusion The overexpression of P21ras and PIK3CA in HCC and hepatic cirrhosis tissue suggests that they participate in the tumorigenesis and development of hepatocellular carcinoma and hepatic cirrhosis, and there may be a signal transduction pathway of P21ras-PI3K in HBV-HCC and HBV-hepatic cirrhosis.

Loss of RASAL1:a new mechanism of ras activation in cancers / 国际肿瘤学杂志

Ras is a kind of protein closely related to neoplasms,the persistent activation of which would induce tumorigenesis and progression.RASAL1 is a Ca~(2+) regulated ras GTPase-activating-like protein, the loss or decreased expression of RASAL1 induces ras activation, then results in tumongenesis and progression.In this review we sum up the mechanism of ras activation, the relationship between neoplasms and RASAL1 and the mechanism of RASAL1 expression decreasing.

Expressions and Significance of p21 Protein and K-ras Protein in Congenital Biliary Dilatation / 实用儿科临床杂志

Objective To investigate the expressions and significance of p21 protein and K-ras protein in congenital biliary dilatation(CBD),and their relationship.Methods Surgical specimens of CBD were obtained during operation on 36 children from Jan.2000 to Sep.2007.Nine normal bile ducts specimens from miscarried fetus and children's corpse.The specimens were fixed in 40 g?L-1 formalin and embeded by paraffin,slice-fixed.SP immunohistochemical method was used to detect the expressions of p21 protein and K-ras protein.Results The positive rate of K-ras protein was 13.8% in CBD,which was significantly higher than that in normal bile duct tissues.The positive rate of p21 protein was 55.6% in CBD,and 100% in normal bile duct tissues.p21 protein positive expression rate in CBD was significantly lower than that in normal bile duct tissues(P