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A subset of autoantibodies produced by patients with systemic lupus erythematosus (SLE) penetrates into cell nuclei and binds DNA, and we believe that such antibodies may have applications in cancer therapy. We have discovered that the cell-penetrating, nuclear-localizing anti-DNA lupus antibody 3E10 inhibits key steps in DNA single- and double-strand break repair and has potential for development as a targeted therapy for tumors harboring deficiencies in DNA repair. 3E10 preferentially binds DNA substrates with free single-strand tails and interferes with both base excision repair and homology-directed repair (HDR) in vitro, and HDR efficiency is reduced in cells treated with 3E10 as measured in the chromosome-based DR-GFP fluorescent reporter assay. The binding of 3E10 to DNA can be directly visualized under electron microscopy (EM), and EM studies confirmed that 3E10 interferes with RAD51 filament formation, which is a critical step in HDR. The 3E10 single chain variable fragment penetrates into human tumor xenografts in nude mice, and 3E10 sensitizes cancer cells and tumors to DNA-damaging therapy. In addition, 3E10, by itself, is toxic to BRCA2-deficient cancer cells but not to repair-proficient cells, and when combined with a DNA-damaging agent, 3E10 has a very large cytotoxic effect on BRCA2-deficient cancer cells. The synthetically lethal effect of 3E10 on BRCA2-deficient cancer cells is consistent with our finding that 3E10 inhibits DNA repair, and it suggests that 3E10 has potential as a targeted therapy for tumors harboring deficiencies in DNA repair, such as certain breast, ovarian, and prostate cancers. Of note, patients with SLE have lower than expected incidence rates of breast, ovarian, and prostate cancers, and it is tempting to speculate that the circulating cell-penetrating anti-DNA autoantibodies provide patients with SLE some protection against the development of DNA repair-deficient tumors. In summary, our work with the 3E10 antibody has provided proof of principle for the development of a lupus antibody as a cancer therapy and opened up new avenues for exploration into the biology of lupus antibodies. Citation Format: James E. Hansen, Grace Chan, Yanfeng Liu, Denise C. Hegan, Shibani Dalal, Eloise Dray, Youngho Kwon, Yuanyuan Xu, Xiaohua Xu, Elizabeth Peterson-Roth, Erik Geiger, Yilun Liu, Joseph Gera, Joann B. Sweasy, Patrick Sung, Sara Rockwell, Robert N. Nishimura, Richard H. Weisbart, Peter M. Glazer. Lupus antibody-based cancer therapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4319. doi:10.1158/1538-7445.AM2013-4319

Background Intermittent preventive treatment in infants (IPTi) with sulphadoxine-pyrimethamine (SP) for the prevention of malaria has shown promising results in six trials. However, resistance to SP is rising and alternative drug combinations need to be evaluated to better understand the role of treatment versus prophylactic effects. Methods Between March 2004 and March 2008, in an area of western Kenya with year round malaria transmission with high seasonal intensity and high usage of insecticide-treated nets, we conducted a randomized, double-blind placebo-controlled trial with SP plus 3 days of artesunate (SP-AS3), 3 days of amodiaquine-artesunate (AQ3-AS3), or 3 days of short-acting chlorproguanil-dapsone (CD3) administered at routine expanded programme of immunization visits (10 weeks, 14 weeks and 9 months). Principal Findings 1,365 subjects were included in the analysis. The incidence of first or only episode of clinical malaria during the first year of life (primary endpoint) was 0.98 episodes/person-year in the placebo group, 0.74 in the SP-AS3 group, 0.76 in the AQ3-AS3 group, and 0.82 in the CD3 group. The protective efficacy (PE) and 95% confidence intervals against the primary endpoint were: 25.7% (6.3, 41.1); 25.9% (6.8, 41.0); and 16.3% (−5.2, 33.5) in the SP-AS3, AQ3-AS3, and CD3 groups, respectively. The PEs for moderate-to-severe anaemia were: 27.5% (−6.9, 50.8); 23.1% (−11.9, 47.2); and 11.4% (−28.6, 39.0). The duration of the protective effect remained significant for up to 5 to 8 weeks for SP-AS3 and AQ3-AS3. There was no evidence for a sustained beneficial or rebound effect in the second year of life. All regimens were well tolerated. Conclusions These results support the view that IPTi with long-acting regimens provide protection against clinical malaria for up to 8 weeks even in the presence of high ITN coverage, and that the prophylactic rather than the treatment effect of IPTi appears central to its protective efficacy. Trial Registration ClinicalTrials.gov NCT00111163

Loss of functional DNA repair pathways is a common occurrence in cancer cells and discovery of novel drugs that selectively kill repair deficient tumors cells could identify new cancer therapies. In this work we describe the use of high-throughput screening to determine chemicals that sensitize cells deficient in the fanconi anemia protein, FANCD2. Cell growth of human fibroblasts proficient (PD20+D2) and deficient (PD20) for FANCD2 were screened using two libraries containing over 1000 bioactive compounds and kinase inhibitors. The cells were treated with compounds continuously for 3 days and cell growth was assessed using a luciferase-based assay measuring ATP levels. The initial screen identified numerous compounds inducing differential survival in cells with and without FANCD2 and follow-up testing will be required to confirm these potential hits. However, it is promising that, in addition to novel compounds, several crosslinking agents, including mitomycinC, which are known to sensitize fanconi anemia cells to cell death are among the positive hits. Our results validate chemical screening as a tool to discover potential new cancer therapies targeting repair deficient cells lines. In addition, other than their role in crosslink repair, there is still not much known about the fanconi anemia protein family and the discovery of novel compounds involved in FANCD2 dependent cell survival could lead to the discovery of new functions of this protein family. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2185.

The endoskeletal structure of tumor cells with a characteristic cytoplasmic abnormality initiated in rat liver by the in vivo adminisration of the carcinogen diethylnitrosamine was studied in clonal cell lines established and propagated in vitro. The bulk of the cytoplasmic and plasma membrane protein was removed by extraction with Triton X-100, and subsequently the juxtanuclear detergent-insoluble fraction containing filaments of 100-150 A was released into citrate buffer at pH 2.8. Analysis of this fraction by sodium dodecyl sulfate acrylamide gel electrophoresis revealed the pressence of five major proteins that banded with apparent molecular weights of about 66, 57, 52, 48 , and 43 x 10(3), the last of which comigrated with actin. The proteins thus resembled those from intermediate-sized filaments of both the vimentin (57 x 10(3)) and the prekeratin types obtained from various vertebrate cells. They also appeared to be related to the polypeptides of intermediate-sized filaments from Mallory bodies induced by griseofulvin in the livers of mice and to some of the polypeptides seen in isolates of Mallory bodies from human alcoholics. These results indicated that a major component of the carcinogen-induced lesion consisted of intermediate-sized filaments. The possible significance in cell transformation of this stably maintained aggregate of filaments that binds concanavalin A and displaces the nucleus is discussed. The close resemblance of this lesion to that seen in the cells of cirrhotic livers of alcoholics (Mallory's alcoholic hyalin) raises a question regarding the possible oncogenic status of such cells in humans.

The gating behavior of human connexin 37 (hCx37) is unaffected by the nature of the bathing monovalent (for Na, K, Rb). It is modified by [Mg] in the millimolar range. For fitting the kinetics, we propose a simple extension to three states of the canonical 2-state model of the hemichannel. The extra closed state allows for some immobilization of a hemichannel at high transjunctional voltages. The model is reasonably efficient at fitting data at various voltage protocols. Interpreting the fits of the data at different [Mg] is consistent with a binding site for Mg.

This study makes use of elicited request speech act data in Finnish to view variability of personal perspective and T/V forms across a variety of situations. The speakers exhibited a great deal of congruency when they were scripted as addressing someone familiar, being in a position of equal or higher status than the interlocutor, and when the request was considered a low imposition. In such situations, speakers tended to use a second person perspective, with informal T/V forms. The Finnish T-forms were found to be the default form, showing up in half of the request utterances. The Finnish V-forms showed up in only 10 percent of the requests. A variationist analysis using Varbrul complemented the main findings, but was found to not be a reliable tool for elicited pragmatic data, using sociopragmatic factors as independent variables.

Background We describe reproductive health issues among pregnant women in a rural area of Kenya with a high coverage of insecticide treated nets (ITNs) and high prevalence of HIV (15%). Methods We conducted a community-based cross-sectional survey among rural pregnant women in western Kenya. A medical, obstetric and reproductive history was obtained. Blood was obtained for a malaria smear and haemoglobin level, and stool was examined for geohelminths. Height and weight were measured. Results Of 673 participants, 87% were multigravidae and 50% were in their third trimester; 41% had started antenatal clinic visits at the time of interview and 69% reported ITN-use. Malaria parasitemia and anaemia (haemoglobin < 11 g/dl) were detected among 36% and 53% of the women, respectively. Geohelminth infections were detected among 76% of the 390 women who gave a stool sample. Twenty percent of women were underweight, and sixteen percent reported symptoms of herpes zoster or oral thrush in the last two months. Nineteen percent of all women reported using a contraceptive method to delay or prevent pregnancy before the current pregnancy (injection 10%, pill 8%, condom 0.4%). Twenty-three percent of multigravidae conceived their current pregnancy within a year of the previous pregnancy. More than half of the multigravidae (55%) had ever lost a live born child and 21% had lost their last singleton live born child at the time of interview. Conclusion In this rural area with a high HIV prevalence, the reported use of condoms before pregnancy was extremely low. Pregnancy health was not optimal with a high prevalence of malaria, geohelminth infections, anaemia and underweight. Chances of losing a child after birth were high. Multiple interventions are needed to improve reproductive health in this area.

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Homomeric gap junction channels are composed solely of one connexin type, whereas heterotypic forms contain two homomeric hemichannels but the six identical connexins of each are different from each other. A heteromeric gap junction channel is one that contains different connexins within either or both hemichannels. The existence of heteromeric forms has been suggested, and many cell types are known to coexpress connexins. To determine if coexpressed connexins would form heteromers, we cotransfected rat connexin43 (rCx43) and human connexin37 (hCx37) into a cell line normally devoid of any connexin expression and used dual whole cell patch clamp to compare the observed gap junction channel activity with that seen in cells transfected only with rCx43 or hCx37. We also cocultured cells transfected with hCx37 or rCx43, in which one population was tagged with a fluorescent marker to monitor heterotypic channel activity. The cotransfected cells possessed channel types unlike the homotypic forms of rCx43 or hCx37 or the heterotypic forms. In addition, the noninstantaneous transjunctional conductance-transjunctional voltage ( G j/ V j) relationship for cotransfected cell pairs showed a large range of variability that was unlike that of the homotypic or heterotypic form. The heterotypic cell pairs displayed asymmetric voltage dependence. The results from the heteromeric cell pairs are inconsistent with summed behavior of two independent homotypic populations or mixed populations of homotypic and heterotypic channels types. The G j/ V jdata imply that the connexin-to-connexin interactions are significantly altered in cotransfected cell pairs relative to the homotypic and heterotypic forms. Heteromeric channels are a population of channels whose characteristics could well impact differently from their homotypic counterparts with regard to multicellular coordinated responses.