Methylation Status of SP1 Sites within miR-23a-27a-24-2 Promoter Region Influences Laryngeal Cancer Cell Proliferation and Apoptosis.

DNA methylation plays critical roles in regulation of microRNA expression and function. miR-23a-27a-24-2 cluster has various functions and aberrant expression of the cluster is a common event in many cancers. However, whether DNA methylation influences the cluster expression and function is not reported.

High microRNA-23a expression in laryngeal squamous cell carcinoma is associated with poor patient prognosis.

Background: MicroRNA-23a (miR-23a) has been demonstrated to play an important role in the development of several types of cancer, but its role in tumorigenesis of laryngeal carcinoma is still unclear. The aim of this study was to investigate the expression patterns and clinical implications of miR-23a in laryngeal cancer.

Methods: Quantitative RT-PCR was performed to evaluate the expression level of miR-23a in 52 pairs of laryngeal cancer.

A very rare case of trisomy 4q32.3-4q35.2 and trisomy 21q11.2-21q22.11 in a patient with recombinant chromosomes 4 and 21.

We report the case of a patient with a clinical phenotype consistent with Down Syndrome (DS) who has a novel karyotypic abnormality. Karyotypic analyses were performed to investigate the cause of two spontaneous abortions. A balanced translocation between chromosomes 4 and 21 was identified, along with an additional abnormal chromosome 21.

Oncogenic miR-23a in Pancreatic Ductal Adenocarcinogenesis Via Inhibiting APAF1.

Background: miR-23a, which participates in invasion of pancreatic ductal adenocarcinoma cells into the mesothelial barrier, is a critical regulator in many cancers. It, however, is still unknown whether miR-23a regulates pancreatic cell proliferation and apoptosis or not.

Aims: We sought to investigate the role of miR-23a in regulation of pancreatic cell proliferation and apoptosis.

MicroRNA-27a promotes proliferation and suppresses apoptosis by targeting PLK2 in laryngeal carcinoma.

Background: miRNA-27a has been confirmed as an important regulator in carcinogenesis and other pathological processes. Whether and how it plays a role in the laryngeal carcinoma is unknown.

Methods: Mature miRNA-27a expression in laryngeal cancer was detected by qRT-PCR.

S100A4 is upregulated via the binding of c-Myb in methylation-free laryngeal cancer cells.

DNA hypomethylation is correlated with the overexpression of the S100A4 gene in several types of cancers including laryngeal cancer, but the molecular mechanism is unknown. We speculated that the methylation status of the promoter affects its binding to the corresponding transcription factors. In the present study, luciferase reporter assay results indicated that the sequences -485 - +73 and -486 - -530 of the S100A4 promoter may harbor the positive and negative cis-acting elements, respectively; and moreover, the luciferase activity promoted by the sequence -485 - +73 increased and the S100A4 gene was significantly upregulated in 5-Aza-induced HEp2 cells.

Promoter hypermethylation-induced transcriptional down-regulation of the gene MYCT1 in laryngeal squamous cell carcinoma.

Background: MYCT1, previously named MTLC, is a novel candidate tumor suppressor gene. MYCT1 was cloned from laryngeal squamous cell cancer (LSCC) and has been found to be down-regulated in LSCC; however, the regulatory details have not been fully elucidated.

Methods: Here, we sought to investigate the methylation status of the CpG islands of MYCT1 and mRNA levels by bisulfite-specific PCR (BSP) based on sequencing restriction enzyme digestion, reverse transcription and real-time quantitative polymerase chain reaction (RQ-PCR).

MYCT1-TV, a novel MYCT1 transcript, is regulated by c-Myc and may participate in laryngeal carcinogenesis.

Background: MYCT1, a putative target of c-Myc, is a novel candidate tumor suppressor gene cloned from laryngeal squamous cell carcinoma (LSCC). Its transcriptional regulation and biological effects on LSCC have not been clarified.

Methodology/principal Findings: Using RACE assay, we cloned a 1106 bp transcript named Myc target 1 transcript variant 1 (MYCT1-TV) and confirmed its transcriptional start site was located at 140 bp upstream of the ATG start codon of MYCT1-TV.

[Molecular and prenatal diagnosis of a pedigree with spinocerebellar ataxia].

Objective: To identify the type of a pedigree with spinocerebellar ataxia, and carry out asymptomatic carrier detection and prenatal diagnosis.

Methods: The blood samples of two patients in the spinocerebellar ataxia pedigree were collected. Based on the clinical characteristics of the pedigree and the disease incidence in China, the regions containing the CAG repeat of the SCA1, SCA2 and SCA3/MJD genes were amplified by polymerase chain reaction (PCR).

[Studies on the mutation and expression of TBX5 gene in human simple congenital heart disease].

This work is to investigate the mutation and expression of TBX5 gene in human simple congenital heart disease. The mutations of eight exons of TBX5 gene in 61 CHD family members (a total of 216 individuals including 65 patients and 151 normal relatives) were examined by PCR-DGGE. Using beta-actin as internal control, the differential expression between 34 myocardium samples from simple congenital heart disease patients and three normal controls was conducted by RT-PCR.

Expression of MTLC gene in gastric carcinoma.

Aim: To investigate the expression of c-myc target from laryngeal cancer cells (MTLC) gene in gastric carcinoma (GC) tissues and the effect of MTLC over-expression on gastric carcinoma cell line BGC823.

Methods: RT-PCR was performed to determine the expression of MTLC mRNA in GC and matched control tissues. BGC823 cells were transfected with an expression vector pcDNA3.

[Analysis on genetic polymorphism of 14 short tandem repeat loci on chromosome 7p14-15 and 12q13 in Chinese north Hans].

Objective: To analyze the genetic polymorphism of 6 short tandem repeat (STR) loci on chromosome 7p14-15 and 8 STR loci on chromosome 12q13 in Chinese north Hans.

Methods: Fluorescence-labeling polymerase chain reaction and capillary electrophoresis were used to analyze the genetic polymorphism of 100 randomly selected individuals from Chinese north Han nationality at 6 STR loci (D7S1808, D7S2250, D7S2251, D7S683, D7S656 and D7S528) on chromosome 7p14-15 and 8 STR loci(D12S1056, D12S1293, D12S83, D12S1655, D12S1662, D12S334, D12S137 and D12S102) on chromosome 12q13.

Results: In the Chinese north Han population, 7 alleles and 24 genotypes, 8 alleles and 27 genotypes, 7 alleles and 22 genotypes, 4 alleles and 10 genotypes, 6 alleles and 17 genotypes, 5 alleles and 13 genotypes were observed at D7S1808, D7S2250, D7S2251, D7S683, D7S656 and D7S528.

Cloning of hTERT cDNA fragment and application of anti-hTERT monoclonal antibody in mechanism of laryngeal carcinogenesis.

The mechanism of telomerase activation is still not clear till now. In order to understand the expressional mode of telomerase and the mechanism of telomerase activation in laryngeal carcinogenesis, we cloned a fragment of hTERT cDNA and prepared a monoclonal antibody against hTERT. We performed immuno-histochemical staining in laryngeal cancer tissues using this antibody.

[Studies of the deletion and expression of cytokeratin 13 gene in laryngeal squamous cell carcinoma].

In order to investigate the role of Cytokeratin 13(CK13) gene in laryngeal carcinogenesis, we detected the deletion of CK13 gene through LOH analysis indirectly at DNA level using 5 STR primers within and near CK13 gene in 72 cases of laryngeal squamous cell carcinoma, then detected the differential expression between 16 cases of paired normal and cancerous tissue by Northern blot, and performed immunohistochemistry using well characterized monoclonal antibody against CK13 in squamous cell carcinoma of different stages. We found that all of the microsatellite loci exist LOH, and the LOH frequencies were 18.03%, 28.