Incidence and risk factors for ocular GVHD after allogeneic hematopoietic stem cell transplantation.

We analyzed the incidence and risk factors for ocular GVHD in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) in Korea. In this retrospective, noncomparative, observational study, 635 subjects were included who had at least 2 years of follow-up ophthalmological examinations after allo-HSCT from 2009 to 2012 at Seoul St Mary's Hospital, Seoul, Korea. The mean duration between allo-HSCT and onset of ocular GVHD was 225.5±194.3 days. The adjusted incidence for acute ocular GVHD was 1.33% and that for chronic GVHD was 33.33%. In the multivariate analysis, preexisting diabetes mellitus (odds ratio (OR): 4.22, 95% confidence interval (CI): 1.66-10.72), repeated allo-HSCT (OR: 29.10, 95% CI: 1.02-8.28) and the number of organs that chronically developed GVHD by stage I (OR: 14.63, 95% CI: 9.81-21.84) increased risk of ocular GVHD. Careful monitoring of ocular GVHD is needed in patients with chronic GVHD in multiple organs and preexisting diabetes.

Q455V mutation in COL8A2 is associated with Fuchs' corneal dystrophy in Korean patients.

PURPOSE: To investigate the possibility of collagen type VIII alpha2 (COL8A2) as a potential susceptibility gene for Korean patients with Fuchs' corneal dystrophy (FECD), we performed mutation screening of the COL8A2 gene. METHODS: A total of 25 FECD patients were screened, including 15 patients from six pedigrees with early onset FECD and an additional 10 unrelated patients, all of Korean ancestry. Seventy-three control individuals without corneal disease were selected from the general population. PCR-SSCP and direct sequencing were used to screen genetic variations in COL8A2. The pathogenic impact of these sequence variants was evaluated through the SIFT and PolyPhen algorithms. RESULTS: We have identified a novel heterozygous mutation, Q455V, in exon 2 of COL8A2. All patients of Korean pedigrees with FECD had the Q455V mutation, and two out of nine unrelated cases also had this mutation. But it was not present in unaffected individuals from these pedigrees or from control groups. Two heterozygous missense mutations, R155Q and T502M, were also observed, but, they showed no significant difference between FECD patients and controls. The allele frequencies of A35A and G495G, which were synonymous substitutions, were significantly associated with FECD. Both Q455V and T502M were predicted as deleterious mutations by computational methods using PolyPhen and SIFT. CONCLUSIONS: Our data constitute the first report of a heterozygous Q455V mutation of the COL8A2 gene in Korean patients with FECD. Q455V may be the causative defect in the development and progression of Korean FECD patients.

Polymorphisms of tumour necrosis factors A and B in breast cancer.

We assayed for germline single nucleotide polymorphisms (SNPs) in the TNFB and TNFA genes in patients with breast cancer. SNPs were observed in the first intron of TNFB (G/A) and at -1031 (T/C), -863 (C/A), -857 (C/T) and -308 (G/A) in the promoter region of TNFA from peripheral leucocytes in 95 breast cancer patients and 190 healthy subjects as controls. The TNFB*G/TNFB*G homozygote (23.2% vs. 5.8%, P= 0.001) was predominant in patients, while the TNFB*A/TNFB*A homozygote was less frequent in patients (34.7% vs. 46.3%, P = 0.041) than in the control subjects. Breast cancer was not associated with SNPs in the TNFA promoters. Although the TNFB SNP failed to associate with any clinicopathological parameter of breast cancer, a substantial difference in pathology among tumour stages for the -857 SNP in TNFA was detected. These results indicate that TNFB has both tumorigenic and antitumorigenic capabilities depending on the genotype: the TNFB SNP TNFB*G/TNFB*G genotype gave an increased risk for breast cancer and that of TNFB*A/TNFB*A gave resistance to breast cancer (OR = 5.3395%; CI: 2.33-12.19). The results suggest that the TNFB*G allele plays some role in the tumorigenesis or activation of dormant tumour cells, but the TNFB*A allele induces some function(s) leading to the inhibition of tumorigenesis.

The 677C > T mutation in 5,10-methylenetetrahydrofolate reductase and colorectal cancer risk.

This paper examines whether there is a relationship between a common mutation in the methylenetetrahydrofolate reductase gene, MTHFR*val, and the risk of colorectal cancer, with or without lymph node metastases. MTHFR genotypes were ascertained from peripheral leukocyte samples obtained from 200 colorectal patients, including TMN stages I-VI, and from 460 healthy, unrelated adults without colorectal cancer, who served as controls. The frequency of homozygosity for the MTHFR*val/*val genotype among the colorectal cancer patients was lower (14.0%) than among controls (16.1%). The latter finding results in an estimated MTHFR*val allele frequency of 0.41. The MTHFR*val allele (677C > T) reduces colorectal risk slightly [odds ratio (OR), 0.87]. However, there was a significantly higher incidence of metastatic lymph nodes per case in MTHFR*val/*val patients, when compared with MTHFR*ala/*ala controls (6.9 +/- 1.55 vs. 3.7 +/- 0.57, p = 0.003). These results suggest that the MTHFR genotype might be of prognostic significance in colorectal carcinoma.

Analysis of TNFB and TNFA NcoI RFLP in colorectal cancer.

We examined the relationship between the NcoI RFLP of tumor necrosis factor beta (TNFB) and alpha (TNFA) genes and the risk of colorectal cancer. The first intron of TNFB and the -308 promoter region of TNFA NcoI RFLP were ascertained from peripheral leucocytes of 136 colorectal cancer patients and 325 healthy controls. The TNFB*1/TNFB*1 homozygote was significantly predominant in patients with colorectal cancer (18.4%) compared to control subjects (9.8%) (p < 0.01), whereas there was inverse association in TNFB*2/TNFB*2. However, the association between colorectal cancer and TNFA genotypes was not found which indicates that these alleles did not appear to be a susceptibility factor for colorectal cancer. TNFB polymorphism was not associated with a clinicopathological parameter of colorectal cancer. However, in regard to the degree of recurrence during the postoperative survival period, TNFB*1/TNFB*1 (12.5%) and TNFB*1/TNFB*2 (24%) were higher than TNFB*2/TNFB*2 (8.3%). Based on these results, it indicates that TNFB*1/TNFB*1 genotypes show an increased risk for colorectal cancer, and that the TNFB*1 allele (R.R. = 1.41) mediates some role in the initial step of tumorigenesis or activation of dormant tumor cells, whereas TNFB*2 allele mediates some functions associated with cytotoxicity of tumor cells.

Analysis of the first intron of TNFB gene by NcoI RFLP in Koreans.

The tumor necrosis factor B (TNFB) gene is closely liked with tumor necrosis factor A (TNFA) gene between the HLA-B and C2 genes on chromosome 6p21.3. Several genetic variabilities at the human TNFB loci have been identified, which are the NcoI restriction fragment length polymorphism (RFLP) in the first intron, amino acid substitution at codon 26 of exon 3 and EcoRI RFLP in untranslated exon 4. The NcoI RFLP of TNFB gene gives two allelic fragments of 238/259 bp and 497 bp, corresponding to TNFB*1 and TNFB*2 alleles, respectively. To investigate the frequency of NcoI RFLP in the first intron of TNFB in Koreans and to compare to that of other ethnic population, genomic DNAs were extracted from leukocytes of 305 unrelated healthy Koreans and amplified the first intron of TNFB gene by PCR. The phenotype frequencies of NcoI RFLP such as TNFB* 1/TNFB*1, TNFB*1/TNFB*2 and TNFB*2/TNFB*2 were 8.6% (n = 26), 45.2% (n = 138) and 46.2% (n = 141), respectively. The estimated allele frequencies for TNFB*1 and TNFB*2 were 0.3115 and 0.6885, respectively. The observed and expected frequencies were in good agreement with the Hardy-Weinberg's equilibrium. The heterozygosity revealed 45.2% and the allele frequencies of NcoI RFLP of TNFB in Koreans were observed comparatively similar to those of other ethnic groups.

NcoI restriction fragment length polymorphism at -308 of the tumor necrosis factor alpha (TNFA) promoter region in Korean.

Tumor necrosis factor alpha (TNFA) is a cytokine, which is secreted from activated macrophage, with a broad range of biological activities. The gene encoding TNFA is located in tandem with the TNFB gene within the HLA complex on chromosome 6p21.3. We detected a single base polymorphism in the human TNFA gene promoter region in 300 unrelated Korean individuals. The TNFA promoter region which showed a G to A transition at position of -308 was investigated by NcoI restriction fragment length polymorphism analysis. A biallelic polymorphism of TNFA gene showed fragments of 87/20 bp and 107 bp acting as TNFA*1 allele and TNFA*2 allele, respectively. The allele frequencies of TNFA*1 and TNFA*2 were 0.8783 and 0.1217, respectively. The 21.7% of heterozygosity was observed. No association between promoter region phenotypes of TNFA and the first intron phenotypes of TNFB was observed in Korean. Allele frequencies of Koreans were compared with that of Europeans.