Citations

AbstractThe American Cancer Society estimates that 73 510 new cases of bladder cancer will be diagnosed and 15 000 deaths will result this year. The paper summarizes the clinical evidence for the use of platinum‐based, non‐platinum‐based and new targeted biological agents, while reporting the future directions in the treatment of metastatic bladder cancer. For cisplatin‐base regimens, the combination of methotrexate, vinblastine, doxorubicin and cisplatin (M‐VAC) has been the mainstream treatment for both advanced and metastatic bladder cancers. It showed significant improvement in the complete response rate and overall survival time in comparison with single‐agent cisplatin. For cisplatin‐ineligible patients, namely patients with renal impairment, symptomatic cardiac disease and poor performance status, alternative therapies consisting of paclitaxel, gemcitabine and carboplatin were shown to be of benefit. Pemetrexed and vinflunine have also shown effectiveness, with small but demonstrable overall survival benefits. Gemcitabine‐based doublet therapies (combined with paclitaxel, docetaxel, irinotecan, oxaliplatin or epirubicin) have all been shown to be effective and well‐tolerated. Several new targeted therapies, such as gefetinib, sorafenib and lapatinib, have received attention in recent years; however, their effectiveness as single agents in a relapse setting have not been optimal and more studies are warranted.

Abstract Transient neonatal zinc deficiency ( TNZD ) has a clinical presentation similar to that of acrodermatitis enteropathica but is caused by a low zinc concentration in maternal breast milk. TNZD becomes clinically evident during breastfeeding and is resolved by weaning and the introduction of complementary nutrition. We present a 4‐month‐old girl with TNZD due to a new autosomal dominant mutation (663delC) in the maternal SLC 30A2 gene not previously described in the literature.

Aneurysmal bone cysts (ABC) are rare, benign, expansile lesions of bone often found in the metaphyses of long bones in pediatric and young adult population. Multiple fluid levels are typically seen on imaging with magnetic resonance imaging (MRI) or computed tomography (CT). We describe a case of a primary ABC in the fibula of a 34-year-old man diagnosed on ultrasound with a mobile fluid level demonstrated sonographically.

Abstract Background: In patients with Barrett's esophagus, chronic reflux injury and inflammation are associated with esophageal adenocarcinoma, one of the most rapidly increasing lethal cancers. Epidemiological and preclinical studies support decreased risk of esophageal adenocarcinoma with NSAID use. Gastroesophageal refluxate contents can promote carcinogenesis in Barrett's metaplasia by activating AKT, which up regulates COX-2 expression and prostaglandin biosynthesis. We recently noted that neoplastic transformation in Barrett's esophagus is associated with increased AKT expression, particularly isoform AKT1. The AIM of this study is to investigate the effect of NSAID (Aspirin) use in patients with Barrett's esophagus on AKT1 expression using frozen tissue from the randomized, phase II trial of aspirin and esomeprazole for esophageal cancer chemoprevention in Barrett's esophagus patients and to assess the functional consequences of AKT1 expression in-vitro. Methods and Results: In a subset of patients (12 of 120 patients) with Barrett's esophagus who were randomized to placebo, lower dose (81 mg) or higher dose (325 mg) Aspirin for 4 weeks, both PCR and Western blot revealed marked reduction in AKT1 expression in patients who received 325 mg of Aspirin daily compared to patients who received placebo. Our in-vitro experiments support that AKT1 expression is functionally relevant to the process of carcinogenesis in Barrett's epithelial cells. Using adenovirus to induce AKT1 expression, we show that increased AKT1 expression increases Barrett's epithelial cell growth, facilitates RAS-mediated transformation of pre-neoplastic epithelial cells and promotes colony formation. Since AKT1 is known as Warburg kinase and regulates cellular glucose uptake to support aerobic glycolysis during growth de-regulation and neoplasia, we examined the uptake of fluorescent deoxyglucose analog (2-NBDG) in Barrett's epithelial cells transduced with AKT1 adenovirus. At 48 hrs, compared to control, AKT1 overexpression resulted in increased glucose uptake both by metaplastic and neoplastic Barrett's epithelial cells. Transcriptional repression of AKT1 abrogated the 2-NBDG uptake by these cells. Finally, we did pathway specific qPCRs and noted that use of Aspirin is associated with altered expression of chromatin remodelers that could down-regulate AKT1 expression. Conclusion: Collectively, our results demonstrate that Aspirin mediated down-regulation of Warburg kinase AKT1 in patients with Barrett?s esophagus is a novel mechanism for the regulation of Barrett?s epithelial cell growth. The in-depth characterization of molecular mechanisms is currently underway. This abstract is also presented as Poster A82. Citation Format: Navtej S. Buttar, Gary W. Falk, Cathrine J. DeMars, Sonia Chowdhury, Ahmed Elebiary, Anamay Sharma, Sidhartha Chaudhry, Nathan R. Foster, Katie L. Allen Ziegler, Yvonne Romero, Norman E. Marcon, Thomas Schnell, Douglas A. Corley, Prateek Sharma, Marcia R. Cruz-Correa, Chin Hur, David E. Fleischer, Amitabh Chak, Kenneth R. DeVault, David S. Weinberg, Gary Della’Zanna, Ellen Richmond, Thomas C. Smyrk, Sumithra Mandrekar, Paul J. Limburg. Aspirin mediated downregulation of Warburg kinase AKT1 in patients with Barrett's esophagus: Implications in neoplastic transformation. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr PR-03.

Abstract Selective Estrogen Receptor Modulators (SERMs) such as tamoxifen and raloxifene can reduce the occurrence of breast cancer in high risk women by approximately 50%. This presentation will describe the use of a genome-wide association study (GWAS) to identify novel genes associated with breast cancer risk during SERM prevention therapy. Those results were pursued by functional genomic experiments that defined mechanisms responsible for the associations observed during the GWAS. These observations not only moved “beyond biomarkers” to function and underlying mechanism, but they also provided novel insight into mechanisms responsible for individual variation in SERM response phenotypes. Citation Format: Richard Weinshilboum. SERM breast cancer pharmaco-genomics: Beyond biomarkers. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr PL04-03.

Abstract Background: Terminal ductal lobular units (TDLUs), the functional units of the breast for lactation, are the structures from which most breast cancers arise. TDLU involution, reflecting atrophy and loss of TDLUs, has been related to lower subsequent breast cancer risk. The predictors of such breast tissue aging, however, are not well defined. Given that estrogens and other hormones play a central role in the etiology of postmenopausal breast cancers, we conducted a study to assess the relationship between four hormones and sex hormone-binding globulin (SHBG) with markers of TDLU involution. Methods: Subjects included healthy women who volunteered between 2009 and 2011 to participate in the Komen Tissue Bank Study. Participants completed a risk factor questionnaire, provided a blood sample, and donated breast tissue for research. Our analysis was restricted to postmenopausal women who were not currently taking menopausal hormones (n=153). A pathologist, masked to patient data, assessed tissue sections for the presence of TDLUs and, among sections containing TDLUs (n=88), measured TDLU diameters for up to ten TDLUs per section. Both presence of TDLUs and TDLU diameter are inversely related to involution. Chemiluminescent immunometric assays were used to measure serum levels of estradiol (E2), SHBG, follicle-stimulating hormone (FSH), and prolactin. Percent free E2 was calculated from measured E2 and SHBG levels. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the presence of TDLUs (none or any) associated with tertiles of serum hormone and SHBG levels. Multivariable ordinal logistic regression was used to calculate ORs, 95% CIs, and p-trend for TDLU diameter categorized as tertiles (≥218.4, 218.4-281, and ≥281 microns) with serum hormone and SHBG levels. All models were adjusted for potential confounding factors. Results: The study population was 87.6% Caucasian with a mean age of 59.5 years, and >2/3 of the women were overweight or obese. Increasing percent free E2 was significantly associated with larger TDLU diameter (OR>2.53 vs. ≥1.99: 5.58, 95% CI: 1.48-21.07; p-trend=0.01), whereas increasing SHBG was associated with smaller TDLU diameter (OR>73nmol/L vs. ≥38 nmol/L: 0.19, 95% CI: 0.05-0.74; p-trend=0.02). Total E2 (p-trend=0.49), FSH (p-trend=0.85), and prolactin (p-trend=0.58) were not associated with TDLU diameter. We did not find significant relationships between the presence of TDLUs and any of the serum levels. Our observed relationships were not modified by age or other breast cancer risk factors, including BMI, years since menopause, and history of bilateral oophorectomy. Conclusion: Based on limited data, these findings suggest that sex hormones may play a role in TDLU involution. Thus, TDLU involution may represent one mechanism by which hormone levels influence breast cancer risk. TDLU measurements may therefore be helpful in assessing breast cancer risk as a marker of breast tissue aging. Analysis of the relationships between hormones and TDLU involution among premenopausal women may provide additional insights into early events in breast carcinogenesis. Citation Format: Zeina G. Khodr, Mark E. Sherman, Ruth M. Pfeiffer, Gretchen L. Gierach, Louise A. Brinton, Roni T. Falk, Deesha Patel, Laura Linville, Susan E. Clare, Daniel Visscher, Carolyn Mies, Stephen Hewitt, Anna Maria Storniolo, Jonine D. Figueroa. Endogenous hormone levels and lobular involution of the breast among healthy, postmenopausal women in the Komen Tissue Bank Study. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr B89.

Abstract We have demonstrated that colorectal cancer (CRC) and advanced pre-cancers can be detected non-invasively by a manual multi-target stool DNA-based test (sDNA-MT) comprising exfoliated DNA markers (methylated BMP3 and NDRG4, mutant KRAS (7 mutations, codons 12, 13), plus β-actin) and fecal hemoglobin (Hb) (Lidgard, Gastroenterology 2012;142(5);S-770). We now report the clinical performance of this sDNA-MT test using an optimized automated analytic platform and logistic algorithm. This platform could facilitate the routine performance of sDNA-MT for CRC screening by molecular diagnostics capable clinical laboratories. Method: Stool samples were collected from 1003 subjects at 36 study sites after informed consent and prior to colonoscopy bowel preparation from those presenting for average risk CRC screening (283) or surveillance (176) at 2 sites. From referred subjects with CRC, Advanced Adenoma (AA) or Sessile Serrate Adenoma ≥ 1 cm, (SSA) stool was collected at least 7 days post-colonoscopy and prior to surgery or chemo-radiation (135; 21 sites) and similarly for subjects with no neoplastic findings on colonoscopy (Neg) (409; 13 sites). The study population included: cases (207), 58% male, median age 65 yrs. (38-87), CRC (93), AA (84), SSA ≥ 1 cm (30) and controls (796), 42% male, median age 65 yrs. (50-84), Neg (641) and non-advanced adenomas (NA) (155). Stool sample collection and DNA isolation were previously described. Automated methylation, mutation and actin assays were performed with a Hamilton STARlet fluid handler (Hamilton Robotics, Reno NV), and QuARTS (Quantitative Allele-specific Real-time Target and Signal amplification) run on an ABI 7500 FastDx real time thermal cycler (Applied Biosystems, Foster City, CA). Fecal Hb (ng/ml buffer) analysis was performed by automated sandwich ELISA. A “Positive” or “Negative” result was determined with an algorithm that included the methylation and mutation results and a logistic regression score, which combines DNA marker results with Hb and actin results. Algorithm results exceeding a threshold were called “Positive”. The algorithm provided good discriminative ability, stability, sensitivity and specificity. Robustness was tested with computer simulations and statistical techniques (leave-one-out and 10-fold cross validation). Results: At a 90% nominal specificity, sDNA-MT sensitivity was 98% for CRC (91/93) [Stage: I, 95% (20/21), II, 100% (23/23), III 96% (26/27), IV 100% (7/7) and I-III combined 97% (69/71)], 57% (65/114) for precursors ≥1 cm (AA, SSA), and 86% (12/14) for precursors with high grade dysplasia. CRC patients were typically referred to colonoscopy for symptoms and test sensitivity may be elevated relative to that seen with screening. Conclusion: With this study using a novel automated sDNA-MT analytic platform with logistic algorithm, we corroborate our earlier findings using a manual process and demonstrate a platform that allows testing to be performed routinely by molecular diagnostic capable laboratories. The high sensitivity of sDNA-MT for CRC across all stages and for advanced precursors with high-grade dysplasia could lead to improved non-invasive CRC screening performance with wide accessibility to patients. A large multi-site pivotal CRC screening study (DeeP-C study clinicaltrials.gov, NCT01397747) to support such use is underway. Citation Format: Graham P. Lidgard, Michael J. Domanico, Janelle J. Bruinsma, James Light, Zubin D. Gagrat, Rebecca L. Oldham-Haltom, Keith D. Fourrier, Hatim Allawi, Tracy C. Yab, Julie A. Simonson, Mary Devens, Russell I. Heigh, David A. Ahlquist, Barry M. Berger. An optimized molecular stool test for colorectal cancer screening: Evaluation of an automated analytic platform and logistic algorithm. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr B12.

Abstract Background: Obesity is postulated to be a major risk factor for pancreatic ductal carcinoma (PDAC), which is the fourth deadliest cancer in the US. Although the association between obesity and pancreatic cancer has been reported, the molecular mechanisms are not yet known. Since K-Ras mutations are almost universal in PDAC, and we have recently shown that endogenous levels of oncogenic K-Ras make cells susceptible to otherwise benign levels of inflammation, we hypothesize that high fat intake can act as a persistent low level inflammatory mechanism capable of inducing PDAC in cells expressing a single copy of oncogenic K-Ras. In the current study, we examined the effects of high dietary fat on the development of precancerous lesions and fibrosis, as well as the activation of K-Ras signaling pathways in mice expressing mutant K-Ras in pancreatic acinar cells. Methods: Transgenic mice LSL-K-Ras were cross with Ela-CreER (Pancreatic-Ras) and treated with tamoxifen to “knock-in” oncogenic K-Ras in adult pancreatic acinar cells. Pancreatic-Ras and littermate control mice were administered a low fat diet with 10.2% kcal fat or a high fat diet with 61.6% kcal fat for 30 days starting at 50 days of age. Mice were then sacrificed and analyzed histologically for fibrosis development, presence of precancerous lesions, and activation of K-Ras signaling pathways. Results: Mice expressing endogenous levels of oncogenic K-Ras and fed a high fat diet developed abundant fibrosis, low grade precancerous lesions throughout the pancreas and had higher levels of phospho-ERK when compared to littermate controls and mice fed a low fat diet. Conclusions: These findings suggest that consumption of high dietary fat acts as an inflammatory stimulus that enhances the activation of oncogenic K-Ras downstream signaling pathways, leading to the early development of precancerous lesions and fibrosis in the pancreas. Therefore, efforts aimed at inhibiting inflammation and K-Ras activation would be expected to prevent cancer development. Citation Format: Zobeida Cruz-Monserrate, Bincy Philips, Baoan Ji, Jaroslaw Daniluk, Craig D. Logsdon. High-fat diet accelerates development of precancerous lesions and fibrosis in mice expressing mutant K-Ras in pancreatic acinar cells. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr B113.

Abstract Increased Ras activity levels due to active mutations of Ras are critical for tumorigenesis. These oncogenic Ras mutations are considered to be locked in a permanent “On” state and “constitutively active”. Yet, surprisingly, expression of oncogenic Ras at physiologically levels in genetically engineered mice with “knock-in” mutant Ras has little effect on most cells. Here, we demonstrated that oncogenic K-Ras is not at all constitutively active. Rather, oncogenic K-Ras can be readily activated by upstream stimulants such as diet-induced hormones (eg. Cholecystokinin) and inflammatory stimuli (eg. PGE2 or LPS). However, unlike wild-type Ras, oncogenic K-Ras is very slow to inactivate. This effect on oncogenic K-Ras signaling kinetics leads to dramatically amplified levels of Ras activity initiated by physiologic stimuli. Sustained increase of Ras activity involves a feed-forward loop in which increased Ras activity generates more inflammatory mediators which act as Ras stimulants. High Ras activity led to acinar cell senescence and generated inflammation and fibrosis resembling the histological features of chronic inflammation with abundant precancerous lesions that spontaneously progressed to cancer only in animals expressing physiologic levels of oncogenic Ras. In summary, oncogenic Ras is not constitutively active but predisposes cells to pathological alterations dependent upon Ras activity levels. Since a large population of normal healthy humans harbors Ras mutations, in addition to targeting Ras downstream signaling pathways a reduction of factors that can activate Ras signaling may provide an important alternative cancer preventive value. These data also provide a mechanistic explanation for the link between inflammation, Ras and cancer and provide insights for cancer prevention. Citation Format: Ji Baoan, Huang Haojie, Liu Yan, Daniluk Jaroslaw, Logsdon Craig. Targeting oncogenic Ras activation for cancer prevention. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr A31.