Evaluation of Radiation Sensitivity in Patients with Hyper IgM Syndrome.

BACKGROUND: HIGM syndrome is a rare form of primary immunodeficiencies characterized by normal/increased amounts of serum IgM and decreased serum levels of other switched immunoglobulin classes. Since the affected patients are continuously infected with various types of pathogens and are susceptible for cancers, diagnostic and therapeutic tests including imaging techniques are recommended for the diagnosis and treatment of these patients, which predispose them to higher accumulated doses of radiation. Given the evidence of class switching recombination machinery defect and its association with an increased rate of DNA repair, we aimed to evaluate radiation sensitivity among a group of patients diagnosed with HIGM syndrome. METHODS: 19 HIGM patients (14 CD40 L and 3 AID deficiencies and 2 unsolved cases without known genetic defects) and 17 control subjects (10 healthy subjects as negative control group, 7 ataxia-telangiectasia patients as positive control group) were enrolled. G2 assay was carried out for the determination of radiosensitivity. RESULTS: Based on radiation-induced chromosomal changes among the studied HIGM patients and their comparison with the controls, almost all (95%) the patients had degrees of radiosensitivity: 6 patients with low to moderate, 1 patient with moderate, 11 patients with severe and 1 patient without radiation sensitivity. CONCLUSION: Today, X-ray radiation plays a very important role in diagnostic and therapeutic procedures; while increased exposure has devastating effects especially in radiosensitive patients. Considering higher sensitivity in HIGM patients, utilizing radiation-free techniques could partly avoid unnecessary and high-level exposure to radiation, thus preventing or reducing its harmful effects on the affected patients.

Relationship Study of The Verified H uman Epidermal Growth Factor Receptor 2 Amplification with Other Tumor Markers and Clinicohistopathological Characteristics in Patients with Invasive Breast Cancer, Using Chromogenic In Situ Hybridization.

OBJECTIVE: Human epidermal growth factor receptor 2 (HER-2), as a crucial factor involved in about 20% of breast cancer cases, is one of the most reliable tumor markers to determine prognosis and therapeutic trend of this disease. This marker is generally assessed by immunohistochemistry (IHC) technique. In the cases that result of IHC test cast doubt (+2), the test should be repeated or validated by applying in situ hybridization techniques, like chromogenic in situ hybridization (CISH). In this regard, the goal of current study was to figure out the link between different clinicopathological characteristics of patients suffering from invasive breast cancer, using tumor markers, hormone receptor (HR) and HER-2. Comparing IHC and CISH techniques for evaluating diagnostic value and usefulness of HER-2 were also the other objective of this study. MATERIALS AND METHODS: Based on this retrospective study, histological markers of 113 individuals suffering from invasive breast cancer -such as estrogen receptor (ER), progesterone receptor, HER-2 receptor, E-cadherin, CK5/6, vimentin and Ki67 were examined by IHC technique. HER-2 amplification of all patients was also evaluated by CISH. Clinicopathological information of the patients was also extracted from medical documents and their associations with tumor markers were statistically evaluated. RESULTS: There is a significant relationship between tumor size, CK5/6 and tumor grade with HR status. Similar relationship was observed between HER-2 status and HR status, as well as vascular invasion (P<0.05). The comparison of HER-2 amplification showed no complete concordance of the result obtained from these two techniques, with score +3. CONCLUSION: Since the status of HER-2 is very important in decision making of the treatment process, CISH technique is recommended in the malignant conditions as the primary test, instead of IHC. In this study, we also determined that HER-2 expression is greatly correlated with ER- and PR- status. This might propose a better prognosis for HER-2+ patients.

G2-lymphocyte chromosomal radiosensitivity in patients with LPS responsive beige-like anchor protein (LRBA) deficiency.

Lipopolysaccharide-responsive, beige-like anchor protein (LRBA) deficiency is an autosomal recessive primary immunodeficiency disease characterized by a CVID-like phenotype, particularly severe autoimmunity and inflammatory bowel disease. This study was undertaken to evaluate radiation sensitivity in 11 LRBA-deficient patients. Therefore, stimulated lymphocytes of the studied subjects were exposed to a low dose γ-radiation (100 cGy) in the G2 phase of the cell cycle and chromosomal aberrations were scored. Lymphocytes of age-sex matched healthy individuals used in the same way as controls. Based on the G2-assay, six (54.5%) of the patients had higher radiosensitivity score comparing to the healthy control group, forming the radiosensitive LRBA-deficient patients. This chromosomal radiosensitivity showed that these patients are predisposed to autoimmunity and/or malignancy, and should be protected from unnecessary diagnostic and therapeutic procedures using ionizing radiation and exposure to other DNA damaging agents.

High frequency of de novo DAZ microdeletion in sperm nuclei of subfertile men: possible involvement of genome instability in idiopathic male infertility.

The occurrence and diagnosis of Y-chromosome microdeletions, specifically deletions of the DAZ (Deleted in Azoospermia) genes are an important issue in male infertility. Screening Y chromosome microdeletion is mainly done using polymerase chain reaction (PCR) on blood leukocytes. However, there is some evidence indicating that presence of DAZ in somatic cells might not be indicative of its presence in the germ cell lineage. Therefore, a total of 130 men with poor semen quality were examined for presence of DAZ microdeletion in their leukocytes. From these, sperm from 40 randomly selected men with no DAZ microdeletions in their leukocytes (n = 10 oligozoospermia; n = 10 asthenozoospermia; n = 10 oligoasthenozoospermia; and n = 10 near-azoospermia) were were compared to sperm from men of normal semen quality (n = 10) using combined primed in situ labelling and fluorescent in situ hybridization (PRINS-FISH) technique as well as screening for sex chromosome aneuploidy. There was an increased frequency of DAZ microdeletion in blood samples from oligozoospermic (5%) (p < 0.05) and near azoospermic patients (14%) (p < 0.01). A high frequency of DAZ microdeletion was observed in the sperm of patients with no DAZ microdeletion in their leukocytes compared to control (p < 0.01). The frequency of sex chromosome aneuploidy also increased, correlating with the severity of infertility in the studied groups. A similar result was observed for sex chromosome aneuploidy. The results might be indicative of DAZ microdeletion induction during spermatogenesis.

High frequency of microdeletion in TTY2 gene family in peripheral blood leukocytes of non-obstructive azoospermia patients.

About 10-15% of non-obstructive azoospermia (NOA) patients show AZFc microdeletion in their blood leukocytes. However, if AZF genes were involved in impaired spermatogenesis, a higher frequency of chromosomal microdeletions was expected. In this study the frequency of AZFc microdeletion was compared with TTY2 gene family, i.e., TTY2A2A and TTY2A12A in blood leukocytes of NOA patients and normal fertile control. In the present study 30 normal fertile individuals with mean age of 35.0 ± 6.0 and 30 NOA patients with mean age of 34.0 ± 7.0 were screened for microdeletion of TTY2L2A and TTY2L12A at Yq11 and Yp11 respectively and sequence-tagged site (STS) markers for AZFc gene using multiplex PCR technique. At the first step karyotyping was done for all subjects using standard G-banding technique to identify patients with normal karyotype as well as non-affected normal controls for molecular analysis. Results showed no AZFc microdeletion in normal and NAO patients whereas one TTY2L2A microdeletion in normal control (3.3%) and 4 in NOA (13.3%) was observed (p < 0.05). However our data indicated that 6 of 30 NOA patients (20%) showed TTY2L12A microdeletion whereas there was no observed microdeletion in normal control (p < 0.01). Results indicate that the studied genes might be involved in impaired spermatogenesis more effective than the routinely screened AZF genes in infertile men. Therefore, screening these genes along with AZF genes might be valuable for infertile patients. The reason why these genes are deleted from Y chromosome is not known but might be associated with genomic instability induced by environmental physico-chemical genotoxic agents.

DNA damage and repair of leukocytes from Fanconi anaemia patients, carriers and healthy individuals as measured by the alkaline comet assay.

Fanconi anaemia (FA) patients show cellular sensitivity to a variety of clastogens and prominently to cross-linking agents. Although there is a long-standing clinical impression of radiosensitivity, in vitro studies have yielded conflicting results. In this study, initial radiation-induced DNA damage and kinetics of DNA repair in (60)Co gamma-irradiated leukocytes from healthy volunteers, FA patients and heterozygotes were assessed using alkaline comet assay. Results showed higher levels of baseline DNA damage in leukocytes of patients and heterozygotes than in controls. Gamma-ray-induced initial DNA damage in leukocytes of FA cases was not significantly different from that of healthy donors and heterozygotes. However, after a repair time of 4 h, following irradiation, samples from the healthy individuals and carriers showed less residual DNA damage in their leukocytes, whereas FA patients revealed more DNA damages than their baseline. Although similar initial induced DNA damage was observed for all groups, the repair kinetics of radiation-induced DNA damage of leukocytes from FA patients was statistically different from healthy and carrier subjects. These findings may suggest that hypersensitivity of FA cells to cross-linking and clastogenic agents might be due to inefficient and delayed repair machinery of these cells. Also, the amount of residual DNA damage after irradiation could be used as a putative predictor of FA screening and cellular radiosensitivity.