Effect of SNX-2112 on proliferation of esophageal cancer cells via regulation of excision repair cross-complementing 1, epidermal growth factor receptor, and p53 expression.

SNX-2112 is a potential molecular targeted therapeutic drug against esophageal cancer (EC). However, its exact mechanism of action remains to be explained. The aim of this study was to investigate the effect of SNX-2112 on excision repair cross- complementing 1 (ERCC1), epidermal growth factor receptor (EGFR), and p53, to elucidate the mechanism of action of SNX-2112 on EC. Fresh tumor sections were surgically obtained from 65 patients with EC, and the expression of ERCC1, EGFR, and p53 was determined by immunohistochemical staining. Furthermore, the effect of SNX-2112 (0.2 µM) on the proliferation of EC-9706 cells and the expression of ERCC1, EGFR, and p53 in these cells were analyzed by a cell proliferation assay and western blot, respectively. We observed a significant decrease and increase in ERCC1 (P = 0.001) and p53 (P = 0.043) expression, respectively, and no significant difference in EGFR (P = 0.59) expression, with the TNM stage of EC, which suggested that ERCC1 and p53 could be potential markers for the TNM stage of EC. We also observed a significant increase in ERCC1 expression, and decrease in p53 and EGFR expression, in EC-9706 cells treated with SNX-2112 (P < 0.05), indicating the regulation of EC by SNX-2112. Furthermore, SNX-2112 treatment induced a significant decrease in the proliferation of EC-9706, which confirmed the function of SNX- 2112. In summary, SNX-2112 inhibits the proliferation of EC cells by regulating the expression of ERCC1, EGFR, and p53.

Study of PIK3CA, BRAF, and KRAS mutations in breast carcinomas among Chinese women in Qinghai.

Phosphatidylinositol-3-OH kinase and RAS-activated signaling pathways play an important role in tumor formation. Abnormalities in relevant genes play essential roles in the occurrence and development of many human cancers. Studies of breast cancer have mainly focused on the women in western countries, but few studies have examined the frequency of mutations in PIK3CA, BRAF, and KRAS in Chinese breast cancer patients. In this study, we conducted sequence analysis of PIK3CA, BRAF, and KRAS and determined relationships with the occurrence of breast cancer in women from Qinghai. DNA was extracted from 25 cases of human breast cancer tissue samples. PIK3CA, BRAF, and KRAS mutation analysis was performed by polymerase chain reaction and DNA sequencing. No mutations were found in PIK3CA, BRAF, and KRAS of adjacent tissues. However, PIK3CA mutations were observed in 32% (8) of the 25 breast cancer tissues examined, in which exon 9 accounted for 4% (1), exon 20 accounted for 28% (7), and no mutations were found in exon 1 of PIK3CA. Sequencing of exon 2 of KRAS suggested that 20% (5) of the 25 samples harbored a mutation and 16% (4) of BRAF harbored a mutation. Any mutation in these 3 oncogenes may induce the occurrence and development of breast cancer.

Significance of sarcomere gene mutation in patients with dilated cardiomyopathy.

Dilated cardiomyopathy (DCM) is a myocardial disease with a high mortality rate. Approximately 40 genes have been found to be associated with DCM to date. Non-familial DCM can also be caused by gene mutations, suggesting that genetic factors were involved in the pathogenesis of DCM; therefore genetic testing is beneficial for the early diagnosis of DCM, which can facilitate the implementation of preventive measures by and within patient's families. Here, we investigated the underlying genetic mutations involved in the cause of patients with DCM. This prospective study included 240 patients with idiopathic DCM and 240 healthy volunteers. Subject clinical data were collected and polymerase chain reaction amplification was carried out on subject DNA for three candidate genes tropomyosin (TPM1), cardiac troponin T type-2 (TNNT2), and nuclear lamina protein A/C. Single nucleotide polymorphism (SNP) loci were detected in the TPM1 (rs1071646) and TNNT2 (rs3729547) genes, respectively. The genotype distributions and allele frequencies were found to satisfy Hardy-Weinberg equilibrium, which indicated that the group was representative. Statistically significant differences were found between the variant frequencies in the two SNP loci between the Kazakh patients with idiopathic DCM (IDCM) and healthy volunteers. A significant difference in the genotype distributions (P = 0.000) and allele frequencies (P = 0.000) of SNP rs1071646, and another significant difference in the genotype distributions (P = 0.000) and allele frequencies (P = 0.039) of SNP rs3729547 between Kazakhs with IDCM and Kazakh controls. These results suggest that the TPM1 (rs1071646) and TNNT2 (rs3729547) gene variants might represent risk factors for patients with DCM in the Kazakh population.

Mechanisms of cytotoxicity induced by the anesthetic isoflurane: the role of inositol 1,4,5-trisphosphate receptors.

Isoflurane can induce widespread cytotoxicity. We hypothesized that isoflurane induces apoptosis partly by causing excessive calcium release from the endoplasmic reticulum (ER) via direct activation of inositol 1,4,5-trisphosphate receptors (IP3R). Rat pheochromocytoma cells cultured for seven days with nerve growth factor were divided into four groups: control group (C), IP3R antagonist group (X), isoflurane group (I) and isoflurane + IP3R antagonist group (I+X). Groups I and I+X were treated with 1 MAC isoflurane for 12 h. Groups X and I+X were pretreated with IP3R antagonist. Annexin V/PI apoptosis and TUNEL assays were performed to evaluate cell apoptosis. TEM was used to observe changes in cell ultrastructure. Changes in calcium concentration ([Ca(2+)]i) in the cytoplasm were measured by flow cytometry. RT-PCR was performed to evaluate IP3R mRNA expression. TEM showed that isoflurane treatment altered cell ultrastructure. Compared to group C, cell apoptosis rate and [Ca(2+)]i increased in groups I and I+X (P < 0.05). Compared to group C, IP3R mRNA expression was lower in group X and higher in group I (P < 0.05). Compared to group X, cell apoptosis rate, [Ca(2+)]i and IP3R mRNA expression increased in groups I and I+X (P < 0.05). Compared to group I, cell apoptosis rate, [Ca(2+)]i and IP3R mRNA expression decreased in group I+X (P < 0.05). These results suggest that exposure to 1 MAC isoflurane for 12 h causes excessive calcium release partly by direct activation of IP3R on the ER membrane and triggers cell apoptosis.

Complete mitochondrial genome sequence of Marmota himalayana (Rodentia: Sciuridae) and phylogenetic analysis within Rodentia.

This is the first report of a complete mitochondrial genome sequence from Himalayan marmot (Marmota himalayana, class Marmota). We determined the M. himalayana mitochondrial (mt) genome sequence by using long-PCR methods and a primer-walking sequencing strategy with genus-specific primers. The complete mt genome of M. himalayana was 16,443 bp in length and comprised 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and a typical control region (CR). Gene order and orientation were identical to those in mt genomes of most vertebrates. The heavy strand showed an overall A+T content of 63.49%. AT and GC skews for the mt genome of the M. himalayana were 0.012 and -0.300, respectively, indicating a nucleotide bias against T and G. The control region was 997 bp in size and displayed some unusual features, including absence of repeated motifs and two conserved sequence blocks (CSB2 and CSB3), which is consistent with observations from two other rodent species, Sciurus vulgaris and Myoxus glis. Phylogenetic analysis of complete mt DNA sequences without the control region including 30 taxa of Rodentia was performed with Maximum-Likelihood (ML) and Bayesian Inference (BI) methods and provided strong support for Sciurognathi polyphyly and Hystricognathi monophyly. This analysis also provided evidence that M. himalayana mt DNA was closely related to that from Sciurus vulgaris (Sciuridae) and was similar to mt DNA from Myoxus glis.

Expression of tyrosine hydroxylase and growth-associated protein 43 in aging atrial fibrillation patients of Xinjiang Uygur and Han nationality.

The aim of this study was to explore the changes in gene and protein expressions of tyrosine hydroxylase (TH) and growth-associated protein 43 (GAP43) in aging atrial fibrillation patients of Xinjiang Uygur and Han nationality, and the significance of the changes. Real-time polymerase chain reaction and Western blot analysis were used to detect gene and protein expressions of TH and GAP43 in atrial tissues of 54 patients with valvular heart disease. mRNA and protein expressions of GAP43 and TH were significantly different between the sinus rhythm and atrial fibrillation groups (P < 0.05). Protein expressions of GAP43 and TH of both nationalities differed significantly between the sinus rhythm group and the atrial fibrillation group (P < 0.05), whereas there was no statistical difference between the two nationalities within each group (P > 0.05). Protein expressions of GAP43 and TH differed significantly among different age groups of different nationalities in the sinus rhythm and atrial fibrillation groups (P < 0.05); only protein expression of GAP43 differed significantly in different age groups in the atrial fibrillation group (P < 0.05). The changes of mRNA and protein expressions of TH and GAP43 played a vital role in the process of maintaining the atrial fibrillation. Therefore, increased expression of TH and GAP43 might be a molecular mechanism for left atrial myoelectricity remodeling of aging atrial fibrillation patients, which might be potential therapeutic targets of atrial fibrillation.

Relationship between serum neopterin levels and coronary heart disease.

The relationship between serum neopterin levels and coronary heart disease (CHD) was investigated. Eighty-six CHD patients were divided into an acute myocardial infarction (AMI) group (N = 21), an unstable angina pectoris (UAP) group (N = 35), and a stable angina pectoris (SAP) group (N = 30), based on coronary angiography (CAG), 30 subjects without CHD served as the control group. Serum neopterin levels were determined by enzyme linked immunosorbent assay (ELISA), and relationships between neopterin and the severity of stenosis, stenosis number, and the stability of coronary artery were analyzed. Serum neopterin levels were higher in the AMI and UAP groups than in the SAP and control groups (P < 0.01), but no significant differences were observed between the AMI and UAP groups or between the SAP and control groups (P > 0.05). Mean serum neopterin levels were higher in the single, double, and three vessel lesion groups than in the control group (P < 0.05), whereas there were no significant differences among the lesion groups (P > 0.05). Serum levels of neopterin were significantly higher in the type II than in the type I or type III, plaque groups (P < 0.01), the incidence of type II plaque was significantly higher in the AMI and UAP groups compared to the SAP group (P < 0.01). Neopterin likely plays a role in the occurrence and development of athermanous plaque and can serve as a useful biomarker of vulnerable plaques. Immunoreaction may be involved in the pathophysiological process of CHD.

Effect of atorvastatin on left atrial function of patients with paroxysmal atrial fibrillation.

The aim of this study was to evaluate the effects of atorvastatin on left atrial (LA) function in paroxysmal atrial fibrillation patients. Fifty-eight paroxysmal atrial fibrillation patients were divided into two groups (treatment and control groups). The echocardiography parameters, including LA active emptying volume (LAAEV), LA active emptying fraction, LA maximum volume, LA total emptying volume, LA total emptying fraction, and LA ejection force (LAEF), were measured before treatment, and then 12 and 18 months after treatment. Compared to pre-treatment levels, the parameters reflecting LA pump function, such as LAAEV and LAEF, decreased significantly in treatment groups 12 months after treatment (P < 0.05). LAAEV and LAEF significantly increased 18 months after treatment (P < 0.05), and the indicators reflecting LA reservoir function, such as maximum volume, total emptying volume, and total emptying fraction increased significantly 18 months after treatment (P < 0.05). Compared with pre-treatment levels, LAAEV and LAEF decreased significantly 18 months after treatment in the control group (P < 0.05). These results demonstrated that long-term atorvastatin treatment could ameliorate the function of the atrium sinistrum.

Comparative analyses of genetic/epigenetic diversities and structures in a wild barley species (Hordeum brevisubulatum) using MSAP, SSAP and AFLP.

We analyzed genetic diversity and population genetic structure of four artificial populations of wild barley (Hordeum brevisubulatum); 96 plants collected from the Songnen Prairie in northeastern China were analyzed using amplified fragment length polymorphism (AFLP), specific-sequence amplified polymorphism (SSAP) and methylation-sensitive amplified polymorphism (MSAP) markers. Indices of (epi-)genetic diversity, (epi-)genetic distance, gene flow, genotype frequency, cluster analysis, PCA analysis and AMOVA analysis generated from MSAP, AFLP and SSAP markers had the same trend. We found a high level of correlation in the artificial populations between MSAP, SSAP and AFLP markers by the Mantel test (r > 0.8). This is incongruent with previous findings showing that there is virtually no correlation between DNA methylation polymorphism and classical genetic variation; the high level of genetic polymorphism could be a result of epigenetic regulation. We compared our results with data from natural populations. The population diversity of the artificial populations was lower. However, different from what was found using AFLP and SSAP, based on MSAP results the methylation polymorphism of the artificial populations was not significantly reduced. This leads us to suggest that the DNA methylation pattern change in H. brevisubulatum populations is not only related to DNA sequence variation, but is also regulated by other controlling systems.