Differential expression of human homeodomain TGIFLX in brain tumor cell lines

Glioblastoma is the most common and the most lethal primary brain cancer. This malignancy is highly locally invasive, rarely metastatic and resistant to current therapies. Little is known about the distinct molecular biology of glioblastoma multiforme [GBM] in terms of initiation and progression. So far, several molecular mechanisms have been suggested to implicate in GBM development. Homeodomain [HD] transcription factors play central roles in the expression of genomic information in all known eukaryotes. The TGIFX homeobox gene was originally discovered in human adult testes. Our previous study showed implications of TGIFLX in prostate cancer and azoospermia, although the molecular mechanism by which TGIFLX acts is unknown. Moreover, studies reported that HD proteins are involved in normal and abnormal brain developments. We examined the expression pattern of TGIFLX in different human brain tumor cell lines including U87MG, A172, Daoy and 1321N1. Interestingly, real time RT-PCR and western blot analysis revealed a high level of TGIFLX expression in A172 cells but not in the other cell lines. We subsequently cloned the entire coding sequence of TGIFLX gene into the pEGFP-N1 vector, eukaryotic expressionvector encoding eGFP, and transfected into the U-87 MG cell line. The TGIFLX-GFP expression was confirmed by real time RT-PCR and UV-microscopic analysis. Upon transfection into U87 cells, fusion protein TGIFLX-GFP was found to locate mainly in the nucleus. This is the first report to determine the nuclear localization of TGIFLX and evaluation of its expression level between different brain tumor cell lines. Our data also suggest that TGIFLX gene dysregulation could be involved in the pathogenesis of some human brain tumors

Mutation screening in the mitochondrial d-loop region of tumoral and non-tumoral breast cancer in Iranian patients

The mitochondrial DNA [mtDNA] mutations in mitochondrial coding and non coding regions seem to be important in carcinogenesis. The aim of this investigation was to evaluate coding region [mttRNA[Phe] and tRNA[Pro]] and non-coding sequence, mitochondrial displacement loop [mtDNA D-loop], in the cancerous and non-cancerous lesions of Iranian patients with breast cancer [BC]. Genomic DNA was extracted from 50 breast tumors and surrounding normal tissue pairs as well as from 50 unrelated normal breast tissues from Iranian Kurdish population. Subsequently, PCR amplification was performed using specific primers, and then PCR products were subjected to direct sequencing. 41 genetic variants were identified in mtDNA D-loop among tumoral and non-tumoral tissues but not in tRNA[Phe] and tRNA[Pro] sequences. Our findings indicated that C182T, 194insT, 285insA and 16342delT were just found in BC tumors whereas 302insC, C309T and C16069T found in both tumors and surrounding normal tissues. Although our findings showed that the observed genetic variations were not restricted to breast cancer tissues, some genetic changes were found only in BC tumors. Our results, in agreement with the evidence from earlier studies, confirm that the mtDNA genetic alterations might be implicated in tumor initiation, progression and development.

Lack of association between the C677T single nucleotide polymorphism of the MTHFR gene and glaucoma in Iranian patients

Glaucoma is a major cause of blindness worldwide. A single nucleotide polymorphism of the MTHFR gene [C677T] has been associated with susceptibility to this disease, although this is controversial in the last decade. In this study, the possible association between the MTHFR C677T polymorphism and the risk of developing primary open angle [POAG] and pseudoexfoliation glaucoma [PEXG] was investigated. For this, a prospective study consisting of 73 POAG, 85 PEXG and 90 matched controls was undertaken in an Iranian population. Genomic DNA was extracted from whole blood. Genotyping of all individuals for the MTHFR C677T polymorphism was conducted using the PCR-RFLP technique. Our findings revealed no significant association between the MTHFR C677T polymorphism in POAG and PEXG compared with controls. Consistent with several other studies, our analysis suggests that the MTHFR C677T polymorphism is unlikely to be a factor contributing to the risk of developing specific forms of glaucoma