A study is presented on the in vivo effect of elevated cAMP levels induced by cholera toxin on the phosphorylation of subunits of the mitochondrial respiratory complexes and their activities in Balb/c 3T3 mouse fibroblast cultures. Treatment of serum-starved fibroblasts with cholera toxin promoted serine phosphorylation in the 18-kDa subunit of complex I. Phosphorylation of the 18-kDa subunit, in response to cholera toxin treatment of fibroblasts, was accompanied by a 2-3-fold enhancement of the rotenone-sensitive endogenous respiration of fibroblasts, of the rotenone-sensitive NADH oxidase, and of the NADH:ubiquinone oxidoreductase activity of complex I. Direct exposure of fibroblasts to dibutyryl cAMP resulted in an equally potent stimulation of the NADH:ubiquinone oxidoreductase activity. Stimulation of complex I activity and respiration with NAD-linked substrates were also observed upon short incubation of isolated fibroblast mitoplasts with dibutyryl cAMP and ATP, which also promoted phosphorylation of the 18-kDa subunit. These observations document an extension of cAMP-mediated intracellular signal transduction to the regulation of cellular respiration.

Epigenetic regulation, has been very scarcely explored in familial breast cancer (BC). In the present study RASSF1A and RAR beta promoter methylation and miR17, miR21, miR 124, and let-7a expression were investigated to highlight possible differences of epigenetic regulation between male and female familial BC, also in comparison with sporadic BC. These epigenetic alterations were studied in 56 familial BC patients (27 males and 29 females) and in 16 female sporadic cases. RASSF1A resulted more frequently methylated in men than women (76% vs. 28%, respectively, P = 0.0001), while miR17 and let-7a expression frequency was higher in women than in men (miR17: 66% in women vs. 41% in men, P < 0.05; let-7a: 45% in women vs. 15% in men, P = 0.015). RASSF1A methylation affected 27.6% of familial BC while 83% of familial cases showed high expression of the gene (P = 0.025); on the contrary, only 17% of familial BC presented RAR beta methylation and 55% of familial cases overexpressed this gene (P = 0.005). Moreover, miR17, miR21, and let-7a resulted significantly overexpressed in familial compared to sporadic BC. RASSF1A overexpression (86% vs. 65%, P = 0.13) and RAR beta overexpression (57% vs. 32%, P = 0.11) were higher in BRCA1/2 carriers even if not statistical significance was reached. BRCA mutation carriers also demonstrated significant overexpression of: miR17 (93% vs. 35%, P = 0.0001), let-7a (64% vs. 16%, P = 0.002), and of miR21 (100% vs. 65%, P = 0.008). In conclusion, the present data suggest the involvement of RASSF1A in familial male BC, while miR17 and let-7a seem to be implied in familial female BC.

Cancer development is related not only to genetic alterations but also to aberrant epigenetic changes that could lead to heritable gene patterns critical for neoplastic initiation and progression. Knowledge of epigenetic regulation in cancer cells is useful for both the understanding of carcinogenesis and for the possibility of using epigenetic drugs. HOX genes deregulation have a crucial role in oncogenesis process and tumor suppression. In this report, the methylation of HOXA1, HOXA9, HOXA10, HOXB13, HNF1B, OTX1, TLX1 genes have been analyzed in patients with hereditary breast cancer. This is the first study analyzing BRCA mutational status of patients with respect to methylation of HOX genes. HOXA10 has been found to be methylated in all patients analyzed but never in healthy subjects. With respect to clinical pathological information, hypermethylation of all studied genes, with the exception of OTX1, was significantly associated with absence of HER2 neu expression (Po0.05). Moreover, hypermethylation of HOXB13, HOXA10 and HOXA1 was associated with a high proliferation index (Mib1X10%, Po0.05) and hypermethylation of HOXB13 and HOXA10 also with high expression of estrogen and progesterone receptors. These preliminary data suggest a possible involvement of HOX genes in familial breast cancer as marker helpful to identify high-risk patients.HOX genes have a crucial role not only in development, receptor signaling, differentiation, motility and angiogenesis, but also in apoptosis; thus, alterations in their expression could have a role in both oncogenesis and tumor suppression and, consequently, in diagnosis and therapy. In particular, HOX gene methylation is atypical in breast cancer tissue compared with normal epithelia 1 and is linked to malignant transformation and tumor aggressiveness. 2 The aim of this study was to analyze the methylation status of a group of HOX genes in familial breast cancer to understand a possible role of their epigenetic regulation with respect to BRCA1-2 mutational status. In fact, it is already known that HOXA9 overexpression slows breast cancer progression, binding the 5 0 promoter region of BRCA1 then modulating its expression. 2 For this reason, methylation of the regulatory genes HOXA1, HOXA9, HOXA10, HOXB13, HNF1B, OTX1, TLX1 has been investigated in high-risk subjects with a familial history of hereditary breast and/or ovarian cancer, with these genes resulting highly involved in breast cancer. 3,4 This is the first study analyzing BRCA mutational status with respect to methylation of HOX genes in hereditary breast cancer subjects.A total of 24 subjects (19 breast cancer affected and 5 healthy relatives from high-risk familial breast cancer) coming from the genetic counseling program of the National Cancer Research Centre of Bari, and a pool of 9 healthy unrelated controls without breast cancer were enrolled. Among the group of 24, subjects #10, #11, #12, #13 and #20 were healthy, BRCA mutated and with a strong history of breast cancer, whereas patients #3, #8 and #23 also had...

Purpose : We previously showed that about 80% of breast cancer patients at high risk to carry mutation in BRCA genes presented at least one polymorphism in these genes which resulted potentially harmful by in silico analysis. In the present paper the genealogic transmission of those polymorphic coding and non coding variants of BRCA genes in family's members has been investigated.Methods: 30 families, enrolled within the Genetic Counselling Program of our Institute, with probands and at least one first degree relative (n=67 family members) available, have been studied for both BRCA1 and BRCA2 pathological mutation and polymorphic variants' transmission.Results: 10 and 6 probands carried mendelian transmitted mutations in BRCA1 and BRCA2, respectively. Polymorphic coding and non coding variants were transmitted in each family's relatives with a frequency ranging from 42% to100% , with similar rate for each SNP in mutated and non mutated families with the only exception of BRCA1 K1183R significantly more frequent in mutated families (p=0.004); conversely, this SNP and BRCA2 N372H, were more frequently present in breast cancer relatives belonging to families in which pathological BRCA mutations were not present. Furthermore, specific haplotypes were transmitted in all relatives as BRCA1 871Leu-1038Gly, present in both BRCA mutated and non mutated families, while BRCA2 289His-991Asp-IVS14+53 C>T present only in BRCAX families suggesting the harmful role of these SNPs. Conclusions:Analysis of SNPs maps and modality of their transmission could identify further susceptibility markers and provide a basis for a better DNA-based cancer classification.

Hereditary breast cancer syndrome was firstly associated with BRCA1 and BRCA2 genes whose mutations confer high risk to develop breast and/or ovarian cancer. Double heterozygosity is a rare condition in which both BRCA1 and BRCA2 mutations are present in a family at the same time.In the current study, a family with double heterozygosity has been reported. Furthermore, for the first time a molecular analysis in both proband lineages, maternal and paternal, has been reported to understand the provenience of both germinal mutations.The case regards a woman that developed breast and ovarian cancer with liver metastasis which presented two mutations, each in the two genes, transmitted from her mother and her father respectively. In this family all available members have been investigated. The concomitantly presence of these peculiar mutations was never reported before suggesting a link with Caucasian population from Southern Italy.