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Allopurinol is now the first-line treatment for managing gout and its increasing usage has brought more gout patients at risk of developing allopurinol-induced hypersensitive reactions. Up to now, our attempts to identify the biomarkers for hypersensitivity to allopurinol are still finite. Besides, the association between drug-induced hypersensitive reactions and some mitochondrial DNA (mtDNA) alterations has been proved but remains unclear in gout patients. In this study, 41 blood samples of gout patients prescribed with allopurinol including 22 hypersensitive and 29 tolerant ones were used to analyze their mtDNA large-scale deletions through PCR and determine the mtDNA deletion level and the copy number by quantitative PCR. The results indicated that the mtDNA large-scale deletions and mtDNA copy number of the hypersensitive group were lower than that of the tolerant one (p < 0.05). However, no association was found between the mtDNA deletion level and the appearance of hypersensitive reactions in gout patients. In addition, the study showed that the mtDNA deletion level and copy number were negatively correlated with the copy numbers of mitochondrial DNA in gout patients (R = -0.3495; p = 0.0119) and allopurinol hypersensitive group (R = -0.6744; p = 0.0005). Thus, a decrease in mtDNA copy number might serve as a potential biomarker for further investigation to assess the risk of hypersensitive reactions to allopurinol in gout patients.

For the prevalence of lung cancer and its poor diagnosis, the seeking of the efficient biomarkers for this disease is an urgent requirement, especially from non-invasive samples such as plasma. The mitochondria DNA (mtDNA) copy number change has been evaluated as a potential indicator of cancer risk, however, there have been few studies regarding mtDNA in plasma derived exosomes. In this study, the mtDNA copy number was measured on 29 plasma exosome samples of patients with non-small cell lung cancer (NSCLC) and 29 plasma exosome samples of cancer-free controls by real-time PCR assay, then being statistically analyzed to evaluate the relationship between these figures and several pathological features of NSCLC patients. As the results, the existence of mtDNA in exosomes isolated from plasma was detected through PCR assay using primers covering most of the mtDNA length. The relative mtDNA copy numbers determined in the exosomes of the disease and control groups were 1619.1 ± 2589.0 and 1207.0 ± 1550.0, respectively, whereas these values in two disease stages were 783.6 ± 759.3 (stage I-II) and 2647.0 ± 3584.0 (stage III-IV). Comparing among these groups, the difference was only statistically significant between the disease groups of stage I-II and stage III-IV (p

The MT-ATP8 gene encodes for A6L protein subunit belonging to the proton channel of the ATP synthase. MT-ATP8 gene’s mutations can affect the structure and function of the ATP synthase, which may cause diseases. In this study, alterations of MT-ATP8 gene were investigated in tumor tissues of patients with breast cancer and control blood samples using PCR combined with direct sequencing and PCR-RFLP methods, data were analyzed using bioinformatics tools and statistical methods. Sequencing results revealed 5 variants of MT-ATP8 gene on 35 breast tumor tissues and 26 blood samples of controls, of which two mutations C8414T and C8417T altered the amino acid sequence of the resulting protein. The C8417T was further screened by PCR-RFLP and was found in 0,98% (1/102) of breast tumor samples. This change lead to substitution of lecine to phenylalanine (L18F) in a highly conserved position of A6L and was predicted as probably damaging to the structure and function of the protein. Additionally, a 9 bp deletion was also observed in a non-coding region of mtDNA in 26,5% (27/102) of breast cancer patients and 27% (7/26) of controls. Thus, these results showed that C8417T variant in the conserved position of MT-ATP8 gene was rare and first identified in a group of breast cancer patients in Vietnam. 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The MT-ATP6 gene encodes for a protein subunit which is central to the proton channel of the ATP synthase. Mutations of MT-ATP6 gene can affect the ATP synthesis and may play an important role in the process of tumorigenesis. The purpose of this study was to identify potential changes of MT-ATP6 gene in pair of tumor and adjacent tissues of 102 patients with breast cancer and in blood samples of 65 controls by using direct DNA sequencing and PCR-RFLP method. Then, statistical analysis was used to analyze the association between some typical changes and pathological features of breast cancer. As a result, 20 changes in the MT-ATP6 gene in 35 examined breast cancer tissues and 13 changes in 26 blood control samples were reported, of which 12 alterations altered the amino acid and a variant, 9183insC, had not been described in the literature so far. Most of the variants had low frequencies from 2.86% to 5.71%. Two variants, G9053A and G8584A, which changed the amino acid sequence and had high frequency, were screened in all samples. Our results indicated that the frequencies of G9053A and G8584A were 21,6% (22/102 cases) and 24,5% (25/102 cases) respectively in tissues of breast cancer patients and 18,5% (12/65 cases) in normal blood controls. However, there was no statistically significant difference in G9053A and G8485A rates between breast cancer patients and controls as well as between mtDNA alterations and the pathological features of breast cancer such as age, size of tumors, number of lymph nodes, size of lymph nodes, T stage, N stage, tumor differentiation and stages of disease. This study showed that the variations of MT-ATP6 gene differed from patient groups. In Vietnamese patients with breast cancer, the rates of G9053A and G8485A were relatively high but these changes were not statistically related to breast cancer.