Nagwa H. A. Hassan

Studies on the genotoxic effect of beryllium chloride and the possible protective role of selenium/vitamins A, C and E

The genotoxic potential of beryllium chloride (BeCl2) was evaluated in vivo in mice using different endpoints. Chromosomal aberrations in bone marrow cells and in spermatocytes as well as sperm abnormalities were determined in the tested mice. The protective role of an orally administered drug consisting of selenium and vitamins A, C and E (selenium-ACE) was also studied. For analysis of chromosomal aberrations, both single and repeated oral treatments for a period of 3 weeks were performed. The doses used were 93.75, 187.50, 375, and 750 mg BeCl2/kg bw, which corresponds to 1/16, 1/8, 1/4, and 1/2 of the experimental LD50. BeCl2 induced a statistically significant increase in the percentage of chromosomal aberrations in both somatic and germ cells, with a dose- and time-response. The percentage of induced chromosomal aberrations was significantly reduced in all BeCl2-treated groups after oral administration of selenium-ACE. Beryllium chloride also induced a significant increase in the percentage of abnormal sperm. This percentage reached values of 9.62 +/- 0.32 and 5.56 +/- 0.31 in mice treated with the highest test dose of BeCl2 and with BeCl2+selenium-ACE, respectively, compared with 1.96 +/- 0.14 for the control. In conclusion, the results demonstrate the genotoxic effect of beryllium chloride and confirm the protective role of selenium-ACE against the genotoxicity of beryllium chloride.

The modifying effect of selenium and vitamins A, C, and E on the genotoxicity induced by sunset yellow in male mice.

The use of food additives in various products is growing up. It has attracted the attention towards the possible correlation between the mutagenic potential of food additives and various human diseases. This work evaluated the protective role of selenium and vitamins A, C and E (selenium ACE)(1) against the genotoxic effects induced by a synthetic food additive, sunset yellow, in mice. Six groups were studied including two control groups (negative and positive control), two groups are given single dose of sunset yellow (either 0.325, 0.65 or 1.3mg/kg body weight(2) alone or with selenium ACE) and two groups are given sunset yellow daily for 1, 2 or 3 weeks (0.325mg/kg b.wt./day alone or with selenium ACE), respectively. The study examined the induction of sister chromatid exchanges (SCEs)(3) in bone-marrow cells, chromosomal aberration in somatic (bone-marrow) and germ cells (spermatocytes) after single and repeated oral treatment, and the induction of morphological sperm abnormalities. The results showed that sunset yellow had genotoxic effects as indicated by increased frequency of SCEs, by chromosomal aberrations in both somatic and germ cells, and by increased morphological sperm abnormalities and DNA fragmentation. The results also indicated that the oral administration of selenium ACE significantly reduced the genotoxic effects of sunset yellow, a result that may support the use of antioxidants as chemopreventive agents in many applications.

Miconazole genotoxicity in mice

The genotoxic effects of miconazole (MC) were studied in mouse bone‐marrow cells and primary spermatocytes at diakinesis metaphase I of meiosis. The ability of miconazole to induce chromosomal aberrations was investigated. Both acute and subacute treatments were tested. Doses were 0.1, 0.5 and 1 mg per animal. Both acute and subacute treatments induced statistically significant dose‐dependent chromosomal aberrations. The effect of miconazole on sperm head morphology was also studied in animals treated for five successive days with the three doses. Morphological sperm head abnormalities increased significantly after treatment with miconazole. The increase was dose‐dependent. These results suggests that miconazole has a genotoxic effect on mice somatic and germ cells.

Expression profiling of cancer-related galectins in acute myeloid leukemia.

Acute myeloid leukemia (AML) is the most common type of leukemia in adults with the lowest survival rate of all the leukemias. It is a heterogeneous disease in which a variety of cytogenetic and molecular alterations have been identified. Some galectins were previously reported to have important roles in cancer-like neoplastic transformation, tumor cell survival, angiogenesis, and tumor metastasis. Previous studies have showed that some galectin family members play a role in various types of leukemia. The present study aims at evaluating and clarifying the diagnostic and prognostic value of the expression of cancer-related galectins in relation to the clinicopathological characters of AML patients. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect expression profile of eight galectin family members (galectin-1, -2, -3, -4, -8, -9, -12, and -13) in 53 newly diagnosed de novo AML patients. The samples were collected from the inpatient clinic at National Cancer Institute (NCI), Cairo University (CU), diagnosed between July 2012 and May 2013. Our results show that patients with lower LGALS12 gene expression have a lower overall survival than those with higher expression (P value <0.026). Moreover, a statistically significant association between the LGALS4 gene expression and patient age is found. Hence, the higher expression of LGALS4 gene is associated with younger age (adjusted P value <0.001). In conclusion, galectin-12 may be a potential prognostic marker for AML.

Cytogenetic effect of griseofulvin in mouse spermatocytes

The genotoxic effects of griseofulvin (GF) in mouse primary spermatocytes at diakinesis metaphase I of meiosis were investigated. Griseofulvin was administered orally as a single dose of 500, 1000, 1500 and 2000 mg kg−1 body wt. and a multiple treatment with a daily dose of 1000 mg kg−1 body wt. for three and five successive doses. Both single and multiple treatment induced a statistically significant increase in the percentage of chromosomal aberrations which have a dose and time‐dependent relationship. The frequency of chromosomal aberrations peaked 6 and 12 h post treatment; with the highest dose of the drug it reached 27.8% ± 0.87 and 27.66% ± 0.48 6 and 12 h respectively, compared with 5.6% ± 0.39 and 5.2% ± 0.48 for the control.

PIK3CA mutations in HER2-positive Breast Cancer Patients; Frequency and Clinicopathological Perspective in Egyptian Patients

Missense mutations in PIK3CA are common in breast cancers. They mostly involve exons 9 and 20 which encode kinase and helical domains of the protein and may result in its activation. PIK3CA activating mutations were previously shown to predict lower pathologic complete response (pCR) in HER2-positive breast cancer cases undergoing neoadjuvant human epidermal growth factor receptor 2-targeting therapy. Hence, the present work was conducted to estimate the mutation frequency in PIK3CA in 51 HER2-positive patients by direct sequencing. Our results showed 8 out of 51 (15.7%) to harbor PIK3CA mutations in either exon 9 or 20, or both. Three patients had mutations in both exons 9 and 20. Seven (13.7%) possess missense mutations in exon 20 which changed the amino acid sequence of the protein (H1047R, M1040I, and G1049G). Only four cases harbored mutations in exon 9, changing the codon sequences (E545K E545A, and R524K). Taking the clinicopathological data to account, the mutation frequency was greater in ductal than lobular carcinomas, in grade II rather than III and in lymph node positive lesions, with a higher HER2 score and which are ER/PR negative. However, none of the correlations proved statistically significant. In conclusion, to the best of our knowledge, the PIK3CA mutation frequency in this study is the first report regarding HER2-positive breast cancer patients in Egypt. Hereby, we highlight a moderate frequency which could be useful in the future as a predictive marker for anti-HER2 therapy.

Molecular and cytogenetic evaluation for potential genotoxicity of hydrocortisone

Abstract Objective To assess the risk of hydrocortisone sodium succinate through different end points of genotoxicity. Methods The study examined the induction of chromosomal aberrations in bone marrow cells, morphological sperm abnormalities, the effect on dominant lethal gene and protein synthesis. Hydrocortisone was given intraperitoneally at three dose levels 26, 39 and 52 mg/kg body weight which was equivalent to the therapeutic doses in man. Results The results showed that single dose treatment with different doses had no effect on chromosomal aberrations. The dose of 52 mg/kg body weight induced significant percentage of chromosomal aberrations in bone marrow cells after repeated treatment for 7 and 14 days. Significant effect of morphological sperm abnormalities was demonstrated only after treatment with the dose of 52 mg/kg body weight. For examining the dominant lethal mutation, male mice were injected with dose of 39 mg/kg body weight for 5 consecutive days. Mating between treated males and virgin untreated females were performed at different time intervals. The results showed that the percentage of fertile mating at 1–7 and 8–14 days reduced to 50% and 60% respectively compared with control group while no effect was recorded at 15–21 days. The percentage of dominant lethal mutation reached 0.32%, 4.4% and 0% in mating intervals respectively indicating pronounced effect of hydrocortisone at the interval 8–14 days which represented by the late spermatids. The results also showed that the repeated treatment with the dose of 52 mg/kg body weight inhibited protein synthesis which contributed to the cytotoxic effect of the drug. Conclusions It is concluded that long term treatment with large doses of hydrocortisone may have genotoxic effect.

Genetic Variation at 15 Autosomal STR Loci Among Seven Egyptian Populations

Egypt is a transcontinental country containing substantial ethnic, cultural, and linguistic diversity among its people. This study was conducted to investigate the genetic variation at 15 AmpFlSTR Identifiler short tandem repeat (STR) loci, D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA, within and between seven Egyptian populations. Samples of 814 unrelated individuals from Northern Coast, Delta, Greater Cairo, Canal governorates, Northern Upper Egypt, Southern Upper Egypt, and Sinai were investigated. All loci were highly polymorphic in all sample populations. The data were analyzed to give information on allele frequencies and other population statistical parameters. After applying Bonferroni correction, the agreement with Hardy–Weinberg equilibrium (HWE) was confirmed for all loci (exact test), and for all loci with the exception of D3S1358, D19S433, and D18S51 (X2 test). The levels of genetic differentiation and the genetic relationships among populations were evaluated by coefficient of genetic differentiation (FST), AMOVA, and genetic distance of Nei. The most differentiated populations were found between Sinai and Southern Upper Egypt. These two populations showed the lowest within-population variation, whereas the population of Greater Cairo showed the highest within-population variation as indicated by the fixation index FIS. The varying levels of genetic relatedness among the populations in relation to their geographical distribution were analyzed using Mantel test. The results demonstrated that the effectiveness of STR markers enhances their value for identifying the genetic variation within and between Egyptian populations.

Abstract A32: The role of microRNA in the regulation of DUSP16 gene and JNK family in hepatocellular carcinoma patients

Introduction: Human hepatocellular carcinoma (HCC) is consider one of the most common and lethal tumors worldwide, HCC is currently the fifth most common solid tumor worldwide and the fourth important cause of cancer-related death. Eighty percent of new cases found in developing countries as Egypt, but the incidence is increasing in economically developed regions, including Japan, Western Europe, and the United States. It has shown that expression level of different miRNAs was correlated with cellular liver processes such as inflammation, hepatocyte regeneration and apoptosis which indicate their important role in many liver diseases including hepatocellular carcinoma. The main objective of the present study is to correlate between the expression levels of liver specific miRNAs with different mitogen activated protein kinase (MAPK) pathway in primary HCC patients. Patients and Methods: The expression level of miRNA targeting MAPK pathway, Dual-Specificity Phosphatase 16 (DUSP16), c-Jun N-terminal kinases (JNK) family (JNK1, JNK2 and JNK3) were detected in tissue biopsy of 38 primary HCC patients as well as 6 healthy controls using qRT-PCR technique. Detection of the protein levels for DUSP16, JNK1 and JNK2 was done using immunohistochemistry (IHC) assay. Results: The correlation between different expressions was done using (statistical method). Significant correlation was observed between 10 miRNAs with mRNA for DUSP16, JNK1, JNK2 and JNK3 (miR-18b; miR-30c; miR-30e; miR-99a; miR-126; miR-194; miR-198; miR-215; miR-455 and miR-455-3p). Highly significant down regulation was detected in JNK2 and JNK3 gene expression in HCC patients as compared to controls with (P value = 0.016, 0.000) respectively. Using IHC assay, 34% (13 out 38) showed DUSP16 (P value Conclusion: Understanding the role of miRNA in MAPK pathway may open new avenue for development novel treatment strategy in primary hepatocellular carcinoma. Citation Format: Marwa Tantawy, Nagwa Hassan, Mohamed Kobaisi, Abdel Hady Abdel Wahab. The role of microRNA in the regulation of DUSP16 gene and JNK family in hepatocellular carcinoma patients. [abstract]. In: Proceedings of the AACR Special Conference on Chromatin and Epigenetics in Cancer; Sep 24-27, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2016;76(2 Suppl):Abstract nr A32.