20 research outputs found
Deletions of Chromosome 1p and 15q are Associated with Aggressiveness of Gastrointestinal Stromal Tumors
Background/PurposeSite-dependent profiles of chromosome imbalances (CIs) have been reported in gastrointestinal stromal tumors (GISTs). However, the role of specific CIs in association with metastasis is not clear.MethodsThirteen resected liver metastatic GISTs, including seven from the stomach and six from the small intestine, were analyzed using comparative genomic hybridization (CGH). The CIs associated with metastatic risk were assessed by comparing them with those identified in our previous study of 25 primary GISTs, including 14 from the stomach and 11 from the small intestine.ResultsSynchronous detection of liver metastasis was found more often in patients with intestinal than gastric GIST (5/6 vs. 2/7, p = 0.048). When compared with the primary tumors, the CI profile of liver metastases was similar in the intestinal group, but became more complex in the gastric group. Deletions of chromosomes 1p and 15q were very common (> 80%) in primary and metastatic tumors of the intestinal group, and exhibited a trend towards increase in the metastatic tumors of the gastric group. Both groups had a doubling in the frequency of 22q deletion in the liver metastases, which was not significantly different. Other CIs, including 9p deletion, increased significantly in the liver metastases of the gastric group, but not in the intestinal group.ConclusionOur results, together with clinical findings, indicated a CGH profile associated with the intrinsic aggressiveness of the GISTs. Deletion of 1p and 15q play a critical role in the acquisition of aggressiveness during early GIST development
Detection of EBV Infection and Gene Expression in Oral Cancer from Patients in Taiwan by Microarray Analysis
Epstein-Barr virus is known to cause nasopharyngeal carcinoma. Although oral cavity is located close to the nasal pharynx, the pathogenetic role of Epstein-Barr virus (EBV) in oral cancers is unclear. This molecular epidemiology study uses EBV genomic microarray (EBV-chip) to simultaneously detect the prevalent rate and viral gene expression patterns in 57 oral squamous cell carcinoma biopsies (OSCC) collected from patients in Taiwan. The majority of the specimens (82.5%) were EBV-positive that probably expressed coincidently the genes for EBNAs, LMP2A and 2B, and certain structural proteins. Importantly, the genes fabricated at the spots 61 (BBRF1, BBRF2, and BBRF3) and 68 (BDLF4 and BDRF1) on EBV-chip were actively expressed in a significantly greater number of OSCC exhibiting exophytic morphology or ulceration than those tissues with deep invasive lesions (P = .0265 and .0141, resp.). The results may thus provide the lead information for understanding the role of EBV in oral cancer pathogenesis
Methyl-CpG-Binding PCR of Bloodspots for Confirmation of Fragile X Syndrome in Males
This study demonstrates that methyl-CpG-binding PCR (MB-PCR) is a rapid and
simple method for detecting fragile X syndrome (FXS) in males, which is
performed by verifying the methylation status of the FMR1 promoter in
bloodspots. Proteins containing methyl-CpG-binding (MB) domains can be
freeze-stored and used as stocks, and the entire test requires only a few hours.
The minimum amount of DNA required for the test is 0.5 ng. At this amount,
detection sensitivity is not hampered, even mixing with excess unmethylated
alleles up to 320 folds. We examined bloodspots from 100 males, including 24
with FXS, in a blinded manner. The results revealed that the ability of MB-PCR to
detect FMR1 promoter methylation was the same as that of Southern blot
hybridization. Since individuals with 2 or more X chromosomes generally have
methylated FMR1 alleles, MB-PCR cannot be used to detect FXS in females
Prevalence of the Fmr1 Mutation in Taiwan Assessed by Large-Scale Screening of Newborn Boys and Analysis of Dxs548-Fraxac1 Haplotype
If carrier women could be identified in time and take appropriate measures, fragile X syndrome (FXS) can be prevented. Wide screening of women to be or in their early pregnancy was considered a good approach to identify carriers without misdetection. Nevertheless, we argued against the cost-effectiveness of implementing such a screening program in Taiwan, due to the lower carrier rate found in our pilot study. To reliably estimate the prevalence of mutant FMR1 gene in Taiwan, we anonymously screened 10,046 newborn boys using bloodspot polymerase chain reaction ( PCR). Among them, the sample from one boy, who was most likely had FXS, failed repeatedly in PCR amplification. The estimated prevalence of premutation (55- 200 CGG repeats) and intermediate alleles (45-54 CGG repeats ) was 1:1,674 (n = 6) and 1:143 (n = 70), respectively. All these estimates were constantly lower than that reported in Caucasian populations, with variable statistic significance. Furthermore, when comparing analyses of the distribution of alleles at the two most often investigated microsatellite loci, DXS548 and FRAXAC1, between 100 control and 28 unrelated fragile X chromosomes, we found no apparent founder haplotype prevalent among the fragile X patients. Because a few founder haplotypes were reportedly prevalent in two thirds of fragile X alleles in Caucasians and in Chinese from Central China, we thus suggested that lack of founder fragile X chromosomes might result in a relatively low prevalence of mutant FMR1 gene in a population, as observed in Taiwan
Discovery of 3-Amino-2-Hydroxypropoxyisoflavone Derivatives as Potential Anti-HCV Agents
Synthesis and anti-hepatitis C virus (anti-HCV) effects of certain 3-amino-2-hydroxy-propoxy isoflavone derivatives, 6a⁻i, were described. The known 3-(3,4-dimethoxyphenyl)-7-(oxiran-2-ylmethoxy)-4H-chromen-4-one (5) was reacted with substituted amines to give the desired isoflavone derivatives, 6a⁻i. Among them, 7-{3-[(3,4-dimethoxy-phenethyl)amino]-2-hydroxypropoxy}-3-(3,4-dimethoxyphenyl)-4H-chromen-4-one (6b) was the most active, exhibiting approximately 2-fold higher anti-HCV effects than standard antiviral drug ribavirin (EC50 of 6.53 vs. 13.16 μM). In addition, compound 6b was less cytotoxic than ribavirin. The selectivity index (SI) of 6b is approximately 2.6-fold higher than ribavirin. The compounds 6e, 6h, and 6i were also found to possess higher anti-HCV effects than ribavirin. Compound 6b was found to inhibit the HCV RNA expression in Ava5 cells in a dose-dependent manner; furthermore, we found that the antiviral mechanism of compounds 6b, 6e, 6h, and 6i gave rise to induction of HO-1 expression. With the HO-1 promoter-based analysis, we found compounds 6b, 6e, 6h, and 6i induced HO-1 expression through increasing Nrf-2 binding activity. Taken together, compound 6b may serve as a potential lead compound for developing novel anti-HCV agents
Chromosomal Gain of 3q and Loss of 11q Often Associated with Nodal Metastasis in Early Stage Cervical Squamous Cell Carcinoma
Cervical cancer remains a health problem among women worldwide. Delineation of genetic changes is critical to understanding the molecular basis of tumor progression, as well as for identifying genetic markers for early identification of patients at high risk for a poor outcome.
Methods: To provide comparative genomic hybridization data for cervical squamous cell carcinoma in Taiwan, and to gain further insight into genetic markers associated with lymph node metastasis of this disease, we performed comparative genomic hybridization analysis of 30 consecutive cases of cervical squamous cell carcinoma (24 stage IB and 6 stage IIB).
Results: The results disclosed that higher staged tumors or those with lymph node metastasis had more chromosomal imbalances. The commonly recurrent chromosomal imbalances were gains of 3q (46.7%), 1q (36.7%) and 8q (20.0%) and losses of 11q (36.7%), 3p (33.3%), 6q (23.3%), and 2q (20.0%). The frequencies of these chromosomal imbalances in stage IB and IIB tumors did not differ significantly. However, when compared with tumors without lymph node metastasis, the loss of 11q14-q22 (5/9 vs. 3/21, p = 0.019) and gains of 3q11-q22 and 3q26-qter (6/9 vs. 5/21, p = 0.026) were significantly more prevalent in tumors with lymph node metastasis.
Conclusion: The results suggest that certain tumor-associated genes residing on 3q and 11q warrant further investigation to elucidate their role in the progression of this disease