ABCC8 R1420H Loss-of-Function Variant in a Southwest American Indian Community: Association With Increased Birth Weight and Doubled Risk of Type 2 Diabetes

Missense variants in KCNJ11 and ABCC8, which encode the KIR6.2 and SUR1 subunits of the β-cell KATP channel, have previously been implicated in type 2 diabetes, neonatal diabetes, and hyperinsulinemic hypoglycemia of infancy (HHI). To determine whether variation in these genes affects risk for type 2 diabetes or increased birth weight as a consequence of fetal hyperinsulinemia in Pima Indians, missense and common noncoding variants were analyzed in individuals living in the Gila River Indian Community. A R1420H variant in SUR1 (ABCC8) was identified in 3.3% of the population (N = 7,710). R1420H carriers had higher mean birth weights and a twofold increased risk for type 2 diabetes with a 7-year earlier onset age despite being leaner than noncarriers. One individual homozygous for R1420H was identified; retrospective review of his medical records was consistent with HHI and a diagnosis of diabetes at age 3.5 years. In vitro studies showed that the R1420H substitution decreases KATP channel activity. Identification of this loss-of-function variant in ABCC8 with a carrier frequency of 3.3% affects clinical care as homozygous inheritance and potential HHI will occur in 1/3,600 births in this American Indian population.

Abstract A249: Navitoclax and veliparib yield cytotoxicity with lower doses than used for single agents in women's cancers

Background: The apoptosis inhibitor Bcl-XL is upregulated in recurrent ovarian (Ov) and breast (Br) cancer(Ca)s. Modest clinical activity with navitoclax, Bcl-2, Bcl-XL inhibitor, was observed in hematologic malignancies, although a significant grade 3/4 thrombocytopenia has been a challenge for the further development of navitoclax. Our phase I/Ib study of olaparib (PARP inhibitor) and carboplatin (NCT00647062) in Ov and BrCa patients with BRCA1/2 mutation showed a change in Bim and Bcl-2 tissue protein quantities measured before and after 1 cycle correlated with the duration of response (r2=-0.86, p=0.007). We hypothesized combination of PARP inhibitor, veliparib, with navitoclax will yield clinical synergy at doses lower than used for single agents in women's cancers, thus with the potential to minimize the thrombocytopenia.

Materials and Method: We have examined cell injury in Ov (SKOV3, OVCAR8) and triple negative breast cancer (MDA-MB231) cell lines. Cell injury was measured with XTT assays. The clinically attainable dosage of navitoclax and veliparib were compared to the IC50 and a physiologically attainable dose was obtained. Protein expression of Bcl-2, Bcl-XL, Mcl-1, an anti-apoptotic protein of the Bcl-2 family, BAG3, a chaperone protein stabilizing and preventing degradation of Mcl-1 were examined using immunoblot to identify potential biomarkers.

Results: Veliparib (up to 50uM) had little single agent activity, up to 11% inhibition of control growth in all cell lines; navitoclax also had limited single agent activity in doses attainable clinically, up to 31% inhibition of control growth at 5uM. Concurrent administration of the two agents yielded a dose dependent increase in cell injury in all cell lines (up to 49% inhibition; p<0.05). Protein expression of Bcl-2 and Bcl-XL was reduced by navitoclax and combination of navitoclax and veliparib showed further reduction in all cell lines. Mcl-1 protein expression was reduced by the combination in all cell lines, although BAG3 was reduced by the combination, only in SKOV3. Further analysis of protein expression, drug effects in soft agar density-independent cultures, and survival assays are in progress in other Br and OvCa cell lines.

Conclusions: These preliminary results suggest that the combination of PARP inhibition and Bcl2/Bcl-XL neutralization may be cooperative in yielding better results than either agent alone. Further studies are ongoing to complete credentialing this novel drug combination.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A249.

Citation Format: Jung-Min Lee, Alyssa Stacy, Minshu Yu, Elise C. Kohn. Navitoclax and veliparib yield cytotoxicity with lower doses than used for single agents in women's cancers. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A249.

Outcome of a tobacco use cessation randomized trial with high-school students

This study analyzed quantitative data on tobacco use and dependency for 3,589 high-school students, qualitative data for 448 students, and outcome data for a randomized trial comparing the efficacy of two cessation interventions and a control condition for 337 students. Data were collected from 1988 through 1992 in California and Illinois as part of a larger longitudinal study. Smokeless tobacco users, but not smokers, were more likely than controls to maintain cessation for 4 months: biochemically validated cessation at 4 months was 6.5% versus 3.2% for smokers and 14.3% versus 0.0% for smokeless tobacco users. Implications and limitations are discussed.

The distribution of advanced practice nurses in Arkansas: gaps in the care of rural underserved populations

PURPOSE

To examine the relationships between advanced practice nurses' (APN) practice sites and economic factors, racial and ethnic characteristics of the populations they serve, and the likelihood of APNs practicing in underserved areas.

DATA SOURCES

Retrospective analysis of U.S. census data and records supplied by the Arkansas State Board of Nursing.

CONCLUSIONS

Nurse practitioners (NPs) were the only APN group with equal distribution in rural or urban areas. Overall, APNs and NPs were more likely to practice in counties with higher rates of poverty and lower education levels.

IMPLICATIONS FOR PRACTICE

More effort needs to be made in recruiting and retaining APNs in rural and underserved areas.

Demographic, psychosocial and behavioral differences in samples of actively and passively consented adolescents

Requiring active consent from parents leads to different self-reports by adolescents than when it is not required. The present study compares self-reported demographic, psychosocial, and behavior variables between those students from whom active consent was and was not obtained. As found in previous studies, fewer minorities, fewer persons who were dissatisfied with school, fewer persons whose parents were of lower educational levels, and fewer cigarette smokers were represented in the sample recruited by active parental consent. Extending on previous work, we found those students whose parents failed to respond to the consent procedure were less likely to live with both parents, were more likely to be latch-key children, placed a lower priority on health, and were higher in risk-taking, lower in self-esteem, and lower in assertiveness than those whose parents had responded. These data further support the suggestion that those children who are omitted from a research study because of lack of action on the part of the parent are at higher risk for a number of health and social problems. These children need to be included in evaluation samples in order to accurately assess the effectiveness of prevention programming. Future studies should employ a passive consent procedure as a means of recruiting a representative subject pool in school-based prevention research.

Biases in the perception of drinking norms among college students

Individual drinking patterns and the perceived typical drinking patterns of close friends and reference groups were assessed in two different studies with college students. In both studies virtually all students reported that their friends drank more than they did. These effects were found across different levels of individual drinking, within different types of samples, across gender of subjects and with different types of questionnaire assessment. In addition, students' estimates of typical or average drinking within their own social living groups were significantly higher than average drinking within the group estimated from self-reports. Because of the consistent, asymmetrical pattern of reports of self and other drinking, it was interpreted that reports of others' drinking were exaggerated. These biases were particularly evident within organized social groups (i.e., fraternities and sororities) but were minimal in reference to "students in general" or "people in general." Results are discussed in terms of cognitive and motivational factors that potentially could promote or excuse excessive drinking practices among college students.

Hospitalization of HIV-seropositive newborns with AIDS-related disease within the first year of life

The purpose of this study was to estimate the proportion of HIV-seropositive newborns hospitalized for an AIDS-related diagnosis within 12 months of birth and to characterize these hospitalizations. The number of HIV-seropositive infants born December 1987 through June 1988 was derived from the blinded New York State Newborn HIV Seroprevalence Study. The number of infants who were born in these same months and hospitalized with an ARD within 12 months of birth was obtained from a data base containing information on all hospital discharges in New York State. Comparisons were made on the basis of month of birth. Of infants born during the study period, 995 tested positive for HIV antibody, and 151 infants (15 percent) were hospitalized with an ARD within 12 months of birth. The 151 ARD cases had a total of 240 hospitalizations, accounting for 5,772 patient days. Fifty-six percent of the ARD cases were diagnosed within six months of birth.

A state population-based statutory reporting of dementias

Dementia registries have been legislated or are under discussion in at least seven states (California, Florida, Maryland, Michigan, South Carolina, Illinois, and Virginia). Future reporting requirements and recommendations for state mandated reporting systems were discussed in February 1988 at the first Alzheimer's Disease Registry Workgroup Meeting, sponsored by the University of South Carolina; Centers for Disease Control; and Alzheimer's Disease and Related Disorders Association (ADRDA). The discussion clearly demonstrated the involvement of medical record professionals in influencing future reporting decisions. As the first state population-based statutory dementia registry, the New York State Alzheimer's Disease and Other Dementias Registry has faced unique problems and developed unique solutions. Both the problems and solutions have been defined with the help of medical record professionals from a variety of reporting institutions. This input occurred through phone calls, correspondence, participation in field trials and through professional organizations. Medical record personnel will continue to play a vital role in both supplying data to the New York State registry and in conceptualizing the needs of future registries in other states.

A study of the reliability and validity of the Holmes alcoholism scale

The Holmes Am Scale was found to have low internal consistency reliability when a Likert-type response format was employed in both a college and in an alcoholic sample (N = 116). Comparison of AM scores between the alcoholic and college groups revealed a significant point-biserial correlation between Am scores and group; alcoholics had the higher mean score. Discriminant analysis resulted in 76.3% correct classification of respondents into their respective group (alcoholic vs. college) on the basis of Am scores. In addition, Am scores were found to be related modestly to self-reports of quantity and frequency of alcohol use in the college sample. Although these results provide support for the validity of the Am scale, its reliability is yet to be established.