Citations

Abstract Inherited BRCA1/2 mutations confer elevated ovarian cancer risk. Knowledge of factors that can improve ovarian cancer risk assessment in BRCA1/2 mutation carriers is important because no effective early detection for ovarian cancers exists. A cohort of 1,575 BRCA1 and 856 BRCA2 mutation carriers was used to evaluate haplotypes at ATM, BARD1, BRIP1, CTIP, MRE11, NBS1, RAD50, RAD51, and TOPBP1 in ovarian cancer risk. In BRCA1 carriers, no associations were observed with ATM, BARD1, CTIP, RAD50, RAD51, or TOPBP1. At BRIP1, an association was observed for one haplotype with a multiple testing corrected P (Pcorr) = 0.012, although no individual haplotype was significant. At MRE11, statistically significant associations were observed for one haplotype (Pcorr = 0.007). At NBS1, we observed a Pcorr = 0.024 for haplotypes. In BRCA2 carriers, no associations were observed with CTIP, NBS1, RAD50, or TOPBP1. Rare haplotypes at ATM (Pcorr = 0.044) and BARD1 (Pcorr = 0.012) were associated with ovarian cancer risk. At BRIP1, two common haplotypes were significantly associated with ovarian cancer risk (Pcorr = 0.011). At MRE11, we observed a significant haplotype association (Pcorr = 0.012), and at RAD51, one common haplotype was significantly associated with ovarian cancer risk (Pcorr = 0.026). Variants in genes that interact biologically withBRCA1 and/or BRCA2 may be associated with modified ovarian cancer risk in women who carry BRCA1/2 mutations. [Cancer Res 2009;69(14):5801–10]

SUMMARYMurine experimental autoimmune thyroiditis (EAT), characterized by thyroid destruction after immunization with thyroglobulin (Tg), has long been a useful model of organ-specific autoimmune disease. More recently, porcine thyroid peroxidase (pTPO) has also been shown to induce thyroiditis, but these results have not been confirmed. When (C57BL/6 × CBA)F1 mice, recently shown to be susceptible to mouse TPO-induced EAT, were immunized with plasmid DNA to human TPO (hTPO) and cytokines IL-12 or GM-CSF, significant antibody (Ab) titres were generated, but minimal thyroiditis was detected in one mouse only from the TPO + GM-CSF immunized group. However, after TPO DNA immunization of HLA-DR3 transgenic class II-deficient NOD mice, thyroiditis was present in 23% of mice injected with TPO + IL-12 or GM-CSF. We also used another marker for assessing the closeness of the model to human thyroid autoimmunity by examining the epitope profile of the anti-TPO Abs to immunodominant determinants on TPO. Remarkably, the majority of the anti-TPO Abs was directed to immunodominant regions A and B, demonstrating the close replication of the model to human autoimmunity. TPO protein immunizations of HLA-DR3 transgenic mice with recombinant hTPO did not result in thyroiditis, nor did immunization of other mice expressing HLA class II transgenes HLA-DR4 or HLA-DQ8, with differential susceptibility to Tg-induced EAT. Moreover, our efforts to duplicate exactly the experimental procedures used with pTPO also failed to induce thyroiditis. The success of hTPO plasmid DNA immunization of DR3+ mice, similar to our reports on Tg-induced thyroiditis and thyrotropin receptor DNA-induced Graves’ hyperthyroidism, underscores the importance of DR3 genes for all three major thyroid antigens, and provides another humanized model to study autoimmune thyroid disease.

p53 acts as a tumor suppressor by inducing both growth arrest and apoptosis. p53-induced apoptosis can occur without new RNA synthesis through an unknown mechanism. In human vascular smooth muscle cells, p53 activation transiently increased surface Fas (CD95) expression by transport from the Golgi complex. Golgi disruption blocked both p53-induced surface Fas expression and apoptosis. p53 also induced Fas-FADD binding and transiently sensitized cells to Fas-induced apoptosis. In contrast, lpr and gld fibroblasts were resistant to p53-induced apoptosis. Thus, p53 can mediate apoptosis through Fas transport from cytoplasmic stores.