Lysine demethylase KDM3A regulates breast cancer cell invasion and apoptosis by targeting histone and the non-histone protein p53

Invasive growth and apoptosis resistance of breast cancer cells are associated with metastasis and disease relapse. Here we identified that the lysine-specific demethylase KDM3A played a dual role in breast cancer cell invasion and apoptosis by demethylating histone and the non-histone protein p53, respectively. While inducing pro-invasive genes by erasing repressive histone H3 lysine 9 methylation, KDM3A promotes chemoresistance by demethylating p53. KDM3A suppressed pro-apoptotic functions of p53 by erasing p53-K372me1 as this methylation site is crucial for the stability of chromatin-bound p53. Unexpectedly, depletion of KDM3A was capable of reactivating mutated p53 to induce the expression of pro-apoptotic genes in breast cancer with mutant p53. Moreover, KDM3A knockdown also potently inhibited tumorigenic potentials of breast cancer stem-like cells and rendered them sensitive to apoptosis induced by chemotherapeutic drugs. Taken together, our results suggest that KDM3A might be a potential therapeutic target for human breast cancer treatment and prevention.

The effect of levodopa benserazide hydrochloride on homocysteinemia levels in patients with Parkinson's disease and treatment of hyperhomocysteinemia

OBJECTIVE

This study aims to investigate hyperhomocysteinemia (HHcy) resulted from treatment in patients with Parkinson's disease (PD) and to evaluate the therapeutic outcome of HHcy.

PATIENTS AND METHODS

Ninety-three newly diagnosed PD patients were divided into Madopar group (treated with Madopar) and non-Madopar group (not treated with Madopar). Plasma Hcy levels were measured. Five months later, 67 patients presenting with HHcy were randomly divided into treatment group (n = 34) (receiving methylcobalamin 500 µg, tid, and folic acid 50 mg, tid, orally) and control group (n = 33).  Madopar dosage was maintained in both groups. MRI examination was performed to detect cerebral ischemia and patients were evaluated by Webster's rating scale. Plasma Hcy levels were measured at 3-month follow-up. Webster's scores and MRI were performed at 6-month follow-up.

RESULTS

At the initial visit, Hcy levels of patients of Madopar group were significantly higher than those of non-Madopar group  (18.52 ± 6.48 µmol/L) vs. (15.78 ± 3.42), p < 0.05]. At 5-month follow-up, patients of the non-Madopar group presented significantly increased Hcy levels (18.97 ± 7.42 µmol/L) compare with pre-treatment Hcy levels (p < 0.05), whereas Hcy levels were slightly increased in patients of Madopar group (20.61 ± 7.87 µmol/L, p > 0.05). In the treatment group, serum Hcy levels were significantly decreased after 3-month treatment with methylcobalamin and folic acid (p < 0.01). However, serum Hcy levels were not significantly changed in patients of the control group. In addition, in the treatment group, no patient presented ischemic stroke with clinical symptoms and four patients were confirmed with new cerebral ischemic and lacunar lesions by MRI examination. However, in the control group, two ischemic strokes with clinical symptoms and 11 new cerebral ischemic and lacunar lesions were detected. Significant differences were observed between two groups (p < 0.05). Furthermore, post-treatment modified Webster scores were significantly decreased than pre-treatment scores for both groups. However, no significant differences were found between groups (p > 0.05).

CONCLUSIONS

Oral administration of Levodopa in the treatment of PD can cause HHcy, which can result in increased occurrence of ischemic stroke. Supplementation of methylcobalamin and folic acid can effectively reduce Hcy level and thereby prevent the occurrence of ischemic stroke.

THE EFFECTS OF A SIMPLE METHOD FOR CRYOPRESERVATION AND THAWING PROCEDURES ON CORD BLOOD DERIVED DC-BASED ESOPHAGEAL CARCINOMA VACCINE

BACKGROUND

Producing sufficient numbers of DCs at one time point and subsequently cryopreserving the generated DCs in ready-for-use aliquots for clinical application is useful in cancer treatment.

OBJECTIVE

To study the effects of a simplified cryopreservation method and thawing procedures acting on the biological characteristics and specific cytotoxic activity of cord blood derived DC-based esophageal carcinoma vaccine.

MATERIALS AND METHODS

CD34+ hematopoietic stem cells were isolated from cord blood using CD34+ Progenitor Cell Isolation Kit by magnetic cell sorting system (MACS). The CD34+ cells were expanded with cytokines as DCs, and fused with EC109 cells by PEG-3600. The fused cells were transferred to a freezing tube without rate-controlled freezing and stored at -80 degree C for three weeks. During cryopreservation, 2.5% DMSO, 2.5% glucose and 10% FCS at final concentration was used as stock solution. After thawing, cells were assayed for Typan blue viability, morphology, immunophenotypes and T-cell stimulatory capacity, and specific CTL activity.

RESULTS

Cryopreservation does not cause significant changes in the phenotypes expression or morphology of the fused cells, and the viability were well preserved (Typan blue viability was 77.2±1.8%). After being stimulated by DC-based esophageal carcinoma vaccine either before or after cryopreservation, the numbers of CD3+T/CD4+T and CD3+T/CD8+T lymphocytes increased obviously, especially for CD3+T/CD4+T, and the ratio of CD4/CD8 changed from 0.85 to 1.29 and 1.25 respectively. Specific CTL activity were well preserved (compare to the fresh fused vaccine, P>0.05).

CONCLUSION

A simple -80 degree C freezing and storage method is practical for cord blood derived DC-based esophageal carcinoma vaccine. It will greatly facilitate the clinical use of DC-based vaccine for immunotherapy.

Metabolic targeting of oncogene MYC by selective activation of the proton-coupled monocarboxylate family of transporters

Deregulation of the MYC oncogene produces Myc protein that regulates multiple aspects of cancer cell metabolism, contributing to the acquisition of building blocks essential for cancer cell growth and proliferation. Therefore, disabling Myc function represents an attractive therapeutic option for cancer treatment. However, pharmacological strategies capable of directly targeting Myc remain elusive. Here, we identified that 3-bromopyruvate (3-BrPA), a drug candidate that primarily inhibits glycolysis, preferentially induced massive cell death in human cancer cells overexpressing the MYC oncogene, in vitro and in vivo, without appreciable effects on those exhibiting low MYC levels. Importantly, pharmacological inhibition of glutamine metabolism synergistically potentiated the synthetic lethal targeting of MYC by 3-BrPA due in part to the metabolic disturbance caused by this combination. Mechanistically, we identified that the proton-coupled monocarboxylate transporter 1 (MCT1) and MCT2, which enable efficient 3-BrPA uptake by cancer cells, were selectively activated by Myc. Two regulatory mechanisms were involved: first, Myc directly activated MCT1 and MCT2 transcription by binding to specific recognition sites of both genes; second, Myc transcriptionally repressed miR29a and miR29c, resulting in enhanced expression of their target protein MCT1. Of note, expressions of MCT1 and MCT2 were each significantly elevated in MYCN-amplified neuroblastomas and C-MYC-overexpressing lymphomas than in tumors without MYC overexpression, correlating with poor prognosis and unfavorable patient survival. These results identify a novel mechanism by which Myc sensitizes cells to metabolic inhibitors and validate 3-BrPA as potential Myc-selective cancer therapeutics.

Aberrant IDH3α expression promotes malignant tumor growth by inducing HIF-1-mediated metabolic reprogramming and angiogenesis

Cancer cells gain a growth advantage through the so-called Warburg effect by shifting glucose metabolism from oxidative phosphorylation to aerobic glycolysis. Hypoxia-inducible factor 1 (HIF-1) has been suggested to function in metabolic reprogramming; however, the underlying mechanism has not been fully elucidated. We found that the aberrant expression of wild-type isocitrate dehydrogenase 3α (IDH3α), a subunit of the IDH3 heterotetramer, decreased α-ketoglutarate levels and increased the stability and transactivation activity of HIF-1α in cancer cells. The silencing of IDH3α significantly delayed tumor growth by suppressing the HIF-1-mediated Warburg effect and angiogenesis. IDH3α expression was associated with the poor postoperative overall survival of lung and breast cancer patients. These results justify the exploitation of IDH3 as a novel target for the diagnosis and treatment of cancers.

Association of the IRF5 SNP rs2004640 with systemic sclerosis in Han Chinese

Systemic sclerosis (SSc) is a complex disease involving multiple genetic factors. An association of the IRF5 polymorphism with SSc was reported in Caucasian populations of Europe and North America, as well as in Japanese populations. The present study aimed to examine whether the SSc-associated SNP rs2004640 of IRF5 gene confer susceptibility to SSc and clinical features of SSc in a Han Chinese population. A Han Chinese cohort consisting of 424 SSc patients and 502 healthy controls were examined in the study. TaqMan assays were carried out to examine the SNP. Exact p-values were obtained (Fisher’s test) from 2x2 tables of allele counts and disease status. SSc patients of Han Chinese showed increased homozygous TT genotype of the rs2004640 (p = 0.027, odds ratio (OR) = 1.4, CI =1.03-1.93), which was significantly associated with pulmonary fibrosis of SSc and ATA-positive SSc of Han Chinese. The lcSSc and ACA-positive SSc of Han Chinese appeared also in association with the increased T allele frequency. However, the Chinese dcSSc did not show any association with the rs2004640. The results were consistent with previous reports in other ethnic populations in supporting the notion that polymorphisms of IRF5 may play an important role in susceptibility to SSc.

MicroRNA-25 promotes gastric cancer migration, invasion and proliferation by directly targeting transducer of ERBB2, 1 and correlates with poor survival

Gastric cancer (GC) is one of the most common tumors and the molecular mechanism underlying its metastasis is still largely unclear. Here, we show that miR-25 was overexpressed in plasma and primary tumor tissues of GC patients with tumor node metastasis stage (III or IV) or lymph node metastasis. MiR-25 inhibition significantly decreased the metastasis, invasion and proliferation of GC cells in vitro, and reduced their capacity to develop distal pulmonary metastases and peritoneal dissemination in vivo. Furthermore, miR-25 repressed transducer of ERBB2, 1 (TOB1) expression by directly binding to TOB1-3'-UTR, and the inverse correlation was observed between the expressions of miR-25 and TOB1 mRNA in primary GC tissues. Moreover, the loss of TOB1 increased the metastasis, invasion and proliferation of GC cells, and the restoration of TOB1 led to suppressed metastasis, invasion and proliferation. The receiver operating characteristics analysis yielded an area under the curve value of 0.7325 in distinguishing the GC patients with death from those with survival. The analysis of optimal cutoff value revealed poor survival in GC patients with high plasma concentrations of miR-25 (>0.2333 amol/μl). Taken together, miR-25 promotes GC progression by directly downregulating TOB1 expression, and may be a noninvasive biomarker for the prognosis of GC patients.

Meta-analysis of the association of dermatomyositis and polymyositis with cancer

BACKGROUND

Although some features of dermatomyositis (DM) and polymyositis (PM) have been reported as possible prognostic indicators for cancer development, previous studies were small in size and were unable to establish a definitive relationship between neoplasms and DM and PM.

OBJECTIVES

To evaluate risk factors for developing malignancies in patients with DM and PM.

METHODS

Meta-analysis of the studies reported in the literature was performed to unveil risk factors for developing cancer among patients with DM and PM. The included studies were either cohort or retrospective case-control studies with information on cancer status. Risk for malignancy was determined as the odds ratio (OR) or weighted mean difference (WMD) with a 95% confidence interval (CI), determined by fixed and random effects models. Stata 10.0 software was used to identify possible publication bias.

RESULTS

Twenty studies with 380 patients and 1575 controls were included in the analysis. The factors that may increase the risk of cancer in patients with DM and PM were older age (WMD 11·41, 95% CI 9·84-12·98), male sex (OR 1·92, 95% CI 1·49-2·48), cutaneous necrosis (OR 5·52, 95% CI 3·49-8·74) and dysphagia (OR 2·41, 95% CI 1·50-3·86), whereas those that may provide protection against cancer included arthritis (OR 0·38, 95% CI 0·24-0·61) and interstitial lung disease (OR 0·32, 95% CI 0·20-0·51).

CONCLUSIONS

Our data suggest that age, sex, cutaneous necrosis, dysphagia, arthritis and lung complications may influence susceptibility to cancer in patients with DM and PM.

Antimicrobial resistance and toxin gene profiles of Staphylococcus aureus strains from Holstein milk

Isolation of Staphylococcus aureus (Staph. aureus) from Holstein milk samples with mastitis and nonmastitis was conducted to estimate its prevalence, antimicrobial resistance and toxin genes. A total of 353 milk samples were collected from three Chinese Holstein herds. Fifty-three Staph. aureus isolates collected from 29 Staph. aureus-positive samples were characterized via antimicrobial susceptibility, toxin genes and Pulsed-field Gel Electrophoresis (PFGE) profiles. The prevalence of Staph. aureus was 4·0-9·5% in mastitic and 7·3-11·5% in nonmastitic samples in the analysed herds. Approximately 61·0% of Staph. aureus strains isolated from mastitis cows were resistant to ≥10 antimicrobials compared with 0% of isolates with nonmastitis. The most frequently observed super antigenic toxin gene was pvl (41·5%) followed by seh + pvl (13·2%). We did not find mecA-positive methicillin-resistant Staph. aureus (MRSA) strains, while mecA-negative MRSA strains were identified in the three herds. PFGE results suggested potential transmission of Staph. aureus strains in different farms. These results open new insights into Staph. aureus transmission and antimicrobial resistance of Holstein dairy cows and into developing strategies for udder health improvement of dairy cattle.

SIGNIFICANCE AND IMPACT OF THE STUDY

Significantly higher levels of antibiotic resistance of Staphylococcus aureus strains were detected in the lactating Holstein milk with clinical mastitis compared with that without clinical mastitis. PFGE results suggest potential transmission of Staph. aureus strains in different dairy farms. The results imply that the dairy farms need to select effective antibiotics in the treatment of Staph. aureus-infected cows and prevent the transmission of Staph. aureus strains from one herd to another.

STAT4 is a genetic risk factor for systemic sclerosis in a Chinese population

Systemic sclerosis (SSc) is an immune-mediated and complex genetic disease. An association of single-nucleotide polymorphisms (SNPs) in the STAT4 gene with SSc has been reported in European Caucasians, North Americans and Japanese. We undertook the current study to examine whether the STAT4 SNPs are also associated with susceptibility to SSc and SSc subsets in a Han Chinese population. A total of 453 Han Chinese patients with SSc and 534 healthy controls were examined in the study. The SNPs rs7574865, rs10168266 and rs3821236 of the STAT4 gene were examined with SNP TaqMan assays. The T-allele carriers of rs7574865 and rs10168266 were strongly associated with the presence of anti-topoisomerase I (ATA) and pulmonary fibrosis in SSc patients, as well as with diffuse cutaneous SSc (dcSSc). The presence of anti-centromere (ACA) and limited cutaneous SSc (lcSSc) did not show significant association with any of the examined SNPs. The results were consistent with previous reports in other ethnic populations in supporting the notion that polymorphisms of STAT4 may play an important role in susceptibility to SSc. It also revealed different genetic aspects of SSc subsets in a Han Chinese population.

Effect of methylprednisolone and edaravone administration on spinal cord injury

BACKGROUND

Spinal cord injury (SCI) is one of the most devastating traumatic conditions that primarily affects young males with an annual incidence of 15-40 cases per million.

AIM

To explore the superior neuroprotective effect of edaravone (ED) on spinal cord injury during maintenance therapy compared with methylprednisolone (MP).

MATERIALS AND METHODS

Sprague-Dawley rat model of spinal cord injury was established by modified Allen's method. Total 114 rats were divided into two groups and then six subgroups individually: A1 (control group, normal saline injection within 8 h), B1 (MP group, MP injection within 8 h), C1(ED group, ED injection within 8 h), A2 (control group, normal saline injection after 8 h), B1 (MP group, MP injection after 8 h), C1 (ED group, ED injection after 8 h). Further, we investigated the changes of histopathology, caspase-3 and Bcl-xL positive cell.

RESULTS

Haemorrhage, swelling, hyperaemia, gliocytes hyperplasia, inflammatory cells infiltration, vacuolar denaturation, and nucleus concentration could be observed, especially in control group. Caspase-3 positive cell was significantly decreased in MP and ED group within 8 h administration, but caspase-3 positive cell was only significantly decreased in ED group after 8 h administration. And B-cell lymphoma extra large (Bcl-xL) was significantly increased in ED group than MP group no matter within 8 h or after 8 h administration.

CONCLUSIONS

More attention should be paid on the time point of MP administration, and ED administration seem to be more effective for maintenance therapy.

Antibiotic resistance of lactic acid bacteria isolated from Chinese yogurts

The aim of this study was to evaluate the susceptibility of 43 strains of lactic acid bacteria, isolated from Chinese yogurts made in different geographical areas, to 11 antibiotics (ampicillin, penicillin G, roxithromycin, chloramphenicol, tetracycline, chlortetracycline, lincomycin, kanamycin, streptomycin, neomycin, and gentamycin). The 43 isolates (18 Lactobacillus bulgaricus and 25 Streptococcus thermophilus) were identified at species level and were typed by random amplified polymorphic DNA analysis. Thirty-five genotypically different strains were detected and their antimicrobial resistance to 11 antibiotics was determined using the agar dilution method. Widespread resistance to ampicillin, chloramphenicol, chlortetracycline, tetracyclines, lincomycin, streptomycin, neomycin, and gentamycin was found among the 35 strains tested. All of the Strep. thermophilus strains tested were susceptible to penicillin G and roxithromycin, whereas 23.5 and 64.7% of Lb. bulgaricus strains, respectively, were resistant. All of the Strep. thermophilus and Lb. bulgaricus strains were found to be resistant to kanamycin. The presence of the corresponding resistance genes in the resistant isolates was investigated through PCR, with the following genes detected: tet(M) in 1 Lb. bulgaricus and 2 Strep. thermophilus isolates, ant(6) in 2 Lb. bulgaricus and 2 Strep. thermophilus isolates, and aph(3')-IIIa in 5 Lb. bulgaricus and 2 Strep. thermophilus isolates. The main threat associated with these bacteria is that they may transfer resistance genes to pathogenic bacteria, which has been a major cause of concern to human and animal health. To our knowledge, the aph(3')-IIIa and ant(6) genes were found in Lb. bulgaricus and Strep. thermophilus for the first time. Further investigations are required to analyze whether the genes identified in Lb. bulgaricus and Strep. thermophilus isolates might be horizontally transferred to other species.

BOLDMirror: a global mirror system of DNA barcode data

DNA barcoding is a novel concept for taxonomic identification using short, specific genetic markers and has been applied to study a large number of eukaryotes. The huge amount of data output generated by DNA barcoding requires well-organized information systems. Besides the Barcode of Life Data system (BOLD) established in Canada, the mirror system is also important for the international barcode of life project (iBOL). For this purpose, we developed the BOLDMirror, a global mirror system of DNA barcode data. It is open-sourced and can run on the LAMP (Linux + Apache + MySQL + PHP) environment. BOLDMirror has data synchronization, data representation and statistics modules, and also provides spaces to store user operation history. BOLDMirror can be accessed at http://www.boldmirror.net and several countries have used it to setup their site of DNA barcoding.

Accuracy of noninvasive quantification of brain NAA concentrations using PRESS sequence: verification in a swine model with external standard

The metabolite ratios had been employed in the field of MR spectroscopy (MRS) for a long period. The main drawback of metabolite ratio is that ratio results are not comparable with absolute metabolite concentration in vivo. The purpose of this study was to examine the accuracy of noninvasive quantification of brain N-acetylaspartate (NAA) concentrations using previously reported MR external standard method. Eight swine were scanned on a GE 1.5 T scanner with a standard head coil. The external standard method was utilized with a sphere filled with NAA, GABA, glutamine, glutamate, creatine, choline chloride, and myo-inositol. The position resolved spectroscopy (PRESS) sequence was used with TE=135 msec, TR=1500 msec, and 128 scan averages. The analysis of MRS was done with SAGE/IDL program. In vivo NAA concentration was obtained using the equation S=N * e(-TE/T₂) * [1-e(-TR/T₁). In vitro NAA concentration was measured by high performance liquid chromatography (HPLC). In the MRS group, the mean concentration of NAA was 10.03 plusmn 0.74 mmol/kg. In the HPLC group, the mean concentration of NAA was 9.22 plusmn 0.55 mmol/kg. There was no significant difference between the two groups (p = 0.46). However, slightly higher value was observed in the MRS group (7/8 swine), compared with HPLC group. The range of differences was between 0.02~2.05 mmol/kg. MRS external reference method could be more accurate than internal reference method. ¹H MRS does not distinguish between N-acetyl resonance frequencies and other N-acetylated amino acids.

Genetic effects of stearoyl-coenzyme A desaturase (SCD) polymorphism on milk production traits in the Chinese dairy population

Stearoyl-CoA desaturase (SCD) is a multifunctional complex enzyme important in the cellular biosynthesis of fatty acids. The present study was to investigate the association of the SCD gene with milk production traits in dairy cattle. Two single nucleotide polymorphisms (SNPs) (g.6926A>G and g.8646A>G) in introns 3 and 4, and three SNPs (g.10153A>G, g.10213T>C and g.10329C>T) in exon 5 were identified with pooled DNA sequencing and genotyped using matrix-assisted laser desorption/ionization time of flight mass spectrometry assay in 752 Chinese Holstein cows. Polymorphism g.10329C>T was predicted to result in an amino acid replacement from alanine to valine in the SCD protein. With a mixed animal model, the significant associations of the five SNPs with 305-day milk, fat and protein yields and protein percentage were determined. We further demonstrated cows with heterozygous genotypes (A/G or C/T) had highest 305 day milk yield, fat yield, protein yield and lowest protein percentage. Heterozygous cows with genotype AG at the g.6926A>G locus showed the greatest milk yield (P < 0.0001), fat yield (P < 0.0001) and protein yield (P < 0.0001) among other heterozygous genotypes at any of the loci. Dominance effects of all identified SNPs on milk, fat and protein yields and protein percentage were significant. Moreover, significant allele substitution effects at g.6926A>G locus on milk yield and at g.10213T>C on protein yield were observed. Five-locus haplotypes and strong linkage disequilibrium (D' > 0.9) between the five SNPs were also observed. The results suggest that identified polymorphisms could be potential genetic markers to improve the production performance of Chinese Holstein.