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185 Background: Breast cancer rates by the NCI show the lowest incidence for young women under 30, Native American/Alaskan Native women and males overall. Using the National Health Interview Survey we set out to investigate what these three very heterogeneous appearing groups seem to have in common in order to possibly detect preventive factors for breast cancer. Methods: The NHIS is a continuous national survey of the US civilian population. The data are collected yearly through in-person computer assisted household interviews. All members of the household 17 years of age and over who are at home at the time of the interview were invited to participate and respond for themselves. Using the data from this survey provided by the Office of Analysis and Epidemiology, National Center for Health Statistics, Centers for Disease Control and Prevention, we controlled for gender, race/ethnicity, poverty level and age. Results: Over 29.5% of all questioned Native American/Alaskan Native women responded to be in good health while only 17.8% of all white women responded the same. The difference in reported health status between white women and white men was not statistically different. For the health status of women in different age groups we found a picture that is reverse to the incidence trend of breast cancer. The older the women, the more likely they were to respond that they were in good health. Conclusions: As can be expected from such heterogeneous groups they did not have one variable in common that might have a preventive effect on breast cancer. The higher estimate of positively reported health status in association with the low incidence of breast cancer of Native American/Alaskan Native women certainly makes it worth investigating the positive attributes associated with this group’s health behavior. Another more unsettling interpretation of the low incidence rate in this population may be attributed to health insurance coverage, 32.5%—more than double the rate of the population of Caucasian females—do not have health insurance coverage which might lead to a lower rate of reported cancer cases.

176 Background: Breast cancer research has identified certain risk factors over the years, which influence a woman's chance of getting the disease. While factors such as personal history of breast abnormalities, age and the occurrence of breast cancer among first-degree relatives have been identified as estimation factors for breast cancer risk, other factors are less conclusive. Increasingly, obesity is being analyzed as a significant risk factor for many cancers and, after tobacco use, may be one of the most modifiable behavioral cancer risk factors. Interestingly when comparing the incidence rate of breast cancer to the obesity rate nationwide many states show a disparity in the two. It may be that other behavioral risk factors are of greater importance. Methods: The US States Mississippi and West Virginia display the highest rates of obesity (over 29.4% of their population display a BMI over 30.0) and the lowest rates in breast cancer incidence nationwide (under 113.9 and 113.5 people per 100.00. residents are diagnosed with cancer each year respectively). We set out to look at various behavioral risk factors to possibly detect an underlying pattern for breast cancer. Using selected metropolitan/micropolitan area risk trend data from the Behavioral Risk Factor Surveillance System from the CDC, we compared median percentages of the following risk factors: health status, exercise, diabetes, flu vaccination, current smoking, binge drinking and obesity. Results: Both states displayed higher percentages in all risk factors compared to the national average except for one in which they were below the national average: binge drinking. Rhode Island and Connecticut, the two states with the highest incidence rates in breast cancer, in turn displayed slightly higher rates of binge drinking compared to the national average. Conclusions: It appears that binge drinking might weigh more than other behavioral factors in terms of risk associated to breast cancer. Future research will need to analyze the interplay and patterns of the various risk factors as well as evaluate the association of mammographic density and alcohol drinking to further investigate the role of alcohol and binge drinking in the development of breast cancer.

The purpose of this study was to analyze effects and interactions of quality of life and cancer in a diverse population. In the last two decades rates of cancer decreased in the general population, yet significant disparities to racial minorities continue to exist, including preventive actions, choice of cancer treatment and quality of life. Since studies have shown that quality of life data can be a significant independent predictor of survival duration for cancer patients, it is highly relevant to analyze racial disparities in regard to this matter. To extract factors that are potentially predictive of or associated with quality of life we analyzed a diverse population of non-cancer individuals as well as individuals who had been diagnosed with one or more forms of cancer (lung, prostate, colon, breast or a combination) using the Cohort V 2002 baseline dataset from the SEER Medicare Health Outcomes Survey linked database. The SF-36® instrument that was used for this resource is a short-form health survey with 36 questions which yields physical and mental health summary measures, allowing us to analyze underlining causes for racial disparities in cancer incidence and treatment, quality of life and several other covariates. Multivariate linear regression models were used for the entire patient sample to estimate the difference among races (White/ Black or African American/ Other) in terms of the standardized mental health score. The covariates we were able to include next to race and mental health in the model were: cancer diagnosis, current treatment, gender, marital status and level of education. With a total of 108,210 patients with valid form, 86.2% were White, 8.4% Black and 5.4% of other race. The cancer rates were 17.8%, 13.0%, and 12.7% respectively and were significantly different among races. Significant mental health score differences exist among races in the non-cancer as well as the cancer population and were found to be significantly lower for the latter. But these differences in the mental score were not statistically significant among different races after adjusting for the covariates. Most importantly significant differences were observed in the mental health scores depending on the type of cancer a patient was treated for. The results that were found in this study indicate a positive relationship between quality of life for cancer patients and the type of cancer they were treated for rather than their race. Racial disparities may thus at least partially be explained by the form of cancer and/or treatment different groups of cancer patients are receiving. Factors that may further influence the mental health status of cancer patients positively include being married, being female and having an education higher than a high school diploma. Future studies will need to analyze further covariates as well as the various specific molecular factors of specific cancer types and/or treatment modalities as underlying causes for racial disparities in cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5019. doi:10.1158/1538-7445.AM2011-5019

Glioblastoma, grade IV malignant glioma based on the WHO classification, is one of the most common brain tumors found in adults and has an average survival time of twelve to sixteen months. The dismal prognosis associated with these tumors is largely due to their ability to grow and proliferate despite radiotherapy, which along with resection and Temozolomide is the current standard of care. A better understanding of the molecular mechanisms that define this malignant phenotype may result in new therapeutic targets and lead to improvements in how patients are treated. Galectin 1(GAL1), a beta-galactosidase binding protein, is strongly expressed in a variety of human cancers and has been shown to be upregulated by irradiation. In this study, we investigated the role of GAL1 upregulation following irradiation in a variety of patient-generated primary cell lines and its role in cell survival. Patient-generated primary cell lines were characterized using a variety of assays such as MTS, Annexin V, and cell viability. Western Blot analysis was performed probing for a variety of proteins implicated in proliferation, motility, and apoptosis. Radiation sensitivities were established by performing Clonogenic Survival Assays comparing the surviving fraction of patient-derived cell lines with established stable cell lines. 6 Gy irradiation upregulated Galectin 1 protein levels in the majority of primary cells used in our study. Furthermore, cell lines which Gal1was upregulated also displayed induction of Phospho-AKT and were significantly less sensitive to irradiation. The combination of GAL1 upregulation and Phosho-AKT induction following irradiation was associated with a significant decrease in the radiosensitization of the patient-derived primary cell lines used in our study. Interestingly, the patient-derived cell lines which showed no upregulation of GAL1 or Phospho-AKT induction displayed markedly increased sensitivity to radiation elucidating an interesting association between GAL1, Phospho-AKT, and radiation-sensitivity. The underlying mechanism by which GAL1 may medicate radioresistence seems to be through AKT activation, a well-documented protein involved in cell survival. Additional studies are ongoing to validate Galectin 1 as a target for radiation sensitization. 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 357.

Purpose: The purpose of the conducted study was to examine a possible therapeutic relevance of Galectin 1 (Gal-1), a beta-galactoside binding protein. Gal-1 is overexpressed in high grade gliomas and leads to increased radioresistance in glioma cell culture models. Inhibition of Gal-1 increases radiosensitivity and thus is a potential therapeutic target for radiation sensitization. P53 has been shown to negatively regulate Gal-1, hence radiosensitivity could possibly be cell cycle mediated. Experimental Design: We used flow cytometry based cell cycle analysis to investigate cell cycle distribution of LN 229 glioma cells following irradiation. LN229 control cell lines and shRNA mediated Gal-1 knockdown LN 229 cell line were exposed to 6 Gy of irradiation and cell cycle analysis was performed. Furthermore Western blot analysis was carried out, probing for multiple proteins implicated in cell proliferation. The phosphorylation status of a variety of phosphorylation sites of p53, Chk1/2 and AKT were examined. Additionally p53-Gal-1 double-knockdown cell lines were created and clonogenic survival assays as well as AnnexinV apoptosis assays were conducted to analyze the influence on radiation sensitivity. Results: The results of the flow cytometry based cell cycle analysis show significant differences between the LN 229 control cell line and the Gal-1 knockdown cell line after irradiation. 24 h after irradiation 77 % of the control line cells are in G1 whereas only 60 % of the Gal-1 knockdown cells are in G1. Previous data has identified differences in the phosphorylation status of Akt in control vs. Gal-1 knockdown glioma cell lines. Phosphorylation of Akt is induced after irradiation. Western blot analysis indicates a reduction of phosphorylated Chk1/2 in Gal1 knockdown cell lines after irradiation. The phosphorylation state of the p53 phosphorylation site, correlating with Chk1/2 activity, exhibit anticipated results. P53-Gal-1 double-knockdown cell lines demonstrate significantly reduced clonogenic survival compared to control cell lines. Conclusions: The finding that less Gal-1 knockdown cells are in G1 phase after irradiation and that there is a reduction in phosphorylated Chk1/2 leads to the conclusion that Gal-1 knockdown abrogates G1 arrest through a Chk1/2 mediated pathway. That means in reverse that Gal-1 can mediate cell cycle arrest, thus potentially can explain Gal-1 mediated radioresistance. Further analysis of Chk1/2 independent phosphorylation sites of p53 is going to be conducted. 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 1077.

The purpose of these experiments was to study the role that Galectin-1 (GAL1) has in Phosphoinositide 3-kinase (PI3K) signaling. GAL1 protein levels have been identified to be significantly upregulated in gliomas. GAL1 levels have also been closely associated with patient survival. The PI3K enzyme converts phosphatidylinositol 4,5-bisphosphate (PIP2) to phosphatidylinositol (3,4,5)-trisphosphate (PIP3). PIP3 serves as a membrane anchor leading to the activation of AKT. PI3K/AKT signaling is important in cancer cell biology because induction of this pathway is associated with increased cell survival, cell cycle progression, and growth. A PIP3 Mass ELISA was performed on cell lysates isolated from wild type (WT) and GAL1 knockdown cells with and without Inslulin-like growth factor 1 (IGF1) stimulation. Briefly, cells were stimulated with 5mM IGF1 followed by cell lysis. Lysates were compared by ELISA for PIP3 levels. Following this an in vitro PI3K assay was done. This assay is designed to measure the activity of a purified PI3K enzyme by detecting PIP2 to PIP3 conversion. Enzyme was incubated with Gal1 alone, LY294002 PI3K inhibitor, or with both Gal1 and the inhibitor. Controls included enzyme only, enzyme with inhibitor, no enzyme, and no substrate. In order to investigate whether a physical interaction was occurring between Gal1 and PI3K, Co-IP experiments were performed. These experiments involved isolation of cell lysates from WT LN229 cells and GAL1 knockdown LN229 cells. Following pulldown, Co-IP's were run on an SDS-PAGE gel, transferred to blots, and probed for GAL1 and p85 α or β. Previous experiments demonstrated a possible role for GAL1 in PI3K signaling and AKT activation. In the PIP3 mass ELISA experiment, WT cells demonstrated elevated cellular PIP3 levels in response to IGF1 stimulation, as expected. GAL1 knockdown cells did not show any increase in PIP3 levels in response to stimulation. We next examined if GAL1 was having a direct effect on PI3K activity. In vitro PI3K reactions showed a specific upregulation of PI3K activity in response to addition of GAL1. In response to 1000-fold changes in GAL1 concentration there was an approximate 2-fold increase in PI3K (p85α/p110α) activity. GAL1 also demonstrated an ability to overcome LY294002 inhibition of the enzyme. Enzyme incubated with both inhibitor and 5uM GAL1 showed 4 times the conversion as compared to enzyme with inhibitor alone. Interaction studies indicate that there is not a physical interaction between GAL1 and either p85 α or β. Future studies characterizing the role of GAL1 in PI3K signaling include repeating the PI3K assay with other PI3K class I isoforms to examine differences. Fluorescence Resonance Energy Transfer (FRET) experiments will also be performed to further test for a physical interaction between PI3K and GAL1. In conclusion GAL1 has demonstrated an ability to effect PI3K activity, and thereby PI3K signaling. However, a physical interaction between GAL1 and PI3K was not observed. 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 301.

11073 Background: There has been a growing interest in investigating the molecular mechanisms leading to treatment resistance in glioblastoma (GBM). The MAPK pathway has been shown to be involved in mediating treatment resistance. Galectin-3 (Gal3) is commonly overexpressed in astrocytic tumors of the brain and has been associated with adverse clinical outcomes. We investigated the role and mechanisms of Gal3 in mediating treatment resistance in GBM through modulating the MAPK pathway. Methods: We investigated Gal3 expression in GBM cell lines (U87, LN18, LN229). We created stable Gal3 knockdown cell lines (Gal3KD), ERK-knockdown (lentiviral shRNA) and constitutively active MEK(MEK2DD plasmid obtained from Dr. Brugge) cell lines. We then evaluated the radiosensitivity, apoptosis, and cell viability of control cell lines treated by non-targeting (NT) vectors as compared to Gal3KD, ERKKD and MEK2DD using clonogenic survival, Annexin V/PI apoptosis, COMET, and cell cycle assays. Signaling cascades were evaluated using Western blot and a GTP-ras pull down assay. Gal3 was also transiently knocked down in MEK2DD and NT cell lines and signaling cascades were analyzed using western blotting. Gal3 binding interactions were identified using co-immunoprecipitation. Results: Gal3 expression was induced in all GBM cell lines following irradiation. Gal3KD showed increased radiosensitivity similar to ERKKD as compared to controls with decreased clonogenic survival, increased DNA damage, increased apoptosis, and increased cell cycle arrest in G1 and G2, while MEK2DD showed enhanced radioresistance. Gal3KD showed reduced p-ERK at baseline followed by a minimal induction of p-ERK with irradiation as compared to controls which have a high level of p-ERK. Overall p-Akt, ERK and Ras-GTP levels were equivalent in Gal3KD and controls. When Gal3 was transiently knocked down in MEK2DD cell line, p-ERK was drastically reduced similar to controls. Gal3 co-immunoprecipitated with ERK. Conclusions: Our results suggest a possible direct novel interaction between Gal3 and ERK in GBMs that is essential for the expression of p-ERK and mediating treatment resistance in GBMs. No significant financial relationships to disclose.