Citations

Abstract BACKGROUND: Biobanks collect and store biological samples and data from participants for use in research by multiple investigators. The Mayo Clinic Biobank was established by the Mayo Clinic Center for Individualized Medicine with a goal to support a wide array of health-related research studies at Mayo Clinic, including cancer studies. The Biobank is not focused on any particular disease, however, through annotation by questionnaires, the Mayo electronic medical record (EMR), and the Mayo Cancer Registry, it is a useful clinical research resource for cancer related studies. METHODS: Recruitment started in April 2009. Our goal is 50,000 enrollees. Eligible subjects are adult Mayo Clinic patients, U.S residents, and able to consent. Mailed invitations were sent to patients with appointments in certain Mayo Clinic departments. Each participant completed a health history questionnaire including a wide variety of health information as well as whether they or their 1st-degree relatives had ever been diagnosed with specific cancers. For self-reported cancers, subjects were asked to provide the age they were first diagnosed. Subjects also provided a blood sample and granted research access to clinically collected specimens and data from their Mayo Clinic record, at enrollment and into the future. All research projects utilizing samples from this resource are required to return to the Biobank the data generated from their projects. RESULTS: In the first three years, 21736 subjects consented to participate (30% response rate). Participants are 58% female, 95% White, and range in age from 18 to 97 with a median age of 62. At enrollment, 74% were residents in Minnesota, 6% in Iowa, 4% in Wisconsin, and 15% in the other states. Twelve percent reported being a current smoker, while 59% were never smokers. The most common self-reported cancers at baseline were non-melanoma skin cancer (n=2950), prostate cancer (n=1107), breast cancer (n=941), melanoma (n=692), colorectal cancer (n=296), cervical cancer (n=240), sarcoma (n=233), urinary/bladder (n=211), lymphoma (n=187), thyroid cancer (n=186), endometrial cancer (n=170), kidney cancer (n=163), lung cancer (n=145). Excluding non-melanoma skin cancer, 16188 (74%) (6516 male, 9672 female) self-reported being cancer free at baseline. Data will be presented on the frequency of incident cancers diagnosed since enrollment in the Biobank. To date, the Biobank has served as a source of controls for 17 cancer related studies on genetic susceptibility, including studies of the breast, colon, myeloma, brain, lung, pancreas, endometrium, and kidneys. CONCLUSIONS: The Mayo Clinic Biobank has quickly been established as a valuable resource for cancer researchers at Mayo Clinic - primarily as a source of controls for genetic studies. As the Biobank continues to grow in sample size and length of follow-up, it will also serve as a cohort study of cancer incidence embedded within an EMR of a large health organization. Citation Format: Janet E. Olson, Euijung Ryu, Kiley J. Johnson, Karen Maschke, Jody A. Morrisette, Mark Liebow, Paul Y. Takahashi, Ruchi G. Sharma, Kari S. Anderson, Matthew A. Hathcock, Jyotishman Pathak, Noralane M. Lindor, Timothy J. Beebe, Stephen N. Thibodeau, James R. Cerhan. The Mayo Clinic Biobank - A growing resource for cancer related studies. [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 2515. doi:10.1158/1538-7445.AM2013-2515

Abstract Hyperactive ERBB/K-RAS signaling is a major menace that drives aggressive tumor growth and metastasis in human cancer. Currently, there are no effective ways to treat late-stage and relapsed human cancers that have oncogenic ERBB/K-RAS mutations that often confer drug resistance, aggressive tumor growth, systemic metastasis, and poor clinical outcome. Therefore, finding novel approaches and new drug targets to inhibit oncogenic ERBB/K-RAS activation is an urgent goal and the major challenge in cancer therapy and treatment. Instead of targeting an upstream signaling module such as EGFR/HER2/KRAS/B-RAF, we targeted the most downstream signaling module in the EGFR/HER2/K-RAS pathway called the SIAH-dependent proteolytic machinery. SIAHs are the human homologs of Seven-In-Absentia (SINA), an evolutionarily conserved RING E3 ligase, an essential downstream signaling module and a critical “gatekeeper” required for proper EGFR/HER2/K-RAS/B-RAF signal transduction. Guided by the insights and fundamental principles learned from the Drosophila RAS signaling pathway, we conducted preclinical studies to dissect SIAH function in the context of ERBB/K-RAS-mediated tumorigenesis and metastasis in human cancer cells and human cancer biospecimens. We found that (1) SIAH is a great prognostic and predictive biomarker for human cancer, and (2) inhibiting SIAH function is highly effective to block tumorigenesis and metastasis against the well-established, late-stage and metastatic pancreatic cancer and triple negative breast cancer (TNBC). These findings demonstrate that SIAH is an attractive and logical new therapeutic target for novel anti-ERBB/oncogenic K-RAS and anticancer therapy in human cancer. Through our work, SIAH has emerged as a new and effective drug target against oncogenic ERBB/K-RAS activation in human cancer cells. Using anti-SIAH molecules to block K-RAS signaling in human cancer is an excellent example of science going “from the bench (basic research in fruit flies) to the bedside (preclinical studies and ultimately clinical trials)”. As a highly evolutionarily conserved E3 ligase and the most downstream “gatekeeper” of EGFR/HER2/K-RAS/B-RAF signaling pathway, SIAH is uniquely and logically positioned to become a next-generation anti-ERBB/anti-K-RAS drug target. Our preclinical studies have demonstrated that “SIAH-dependent proteolysis” is indeed an Achilles' heel in human cancer. Knowledge gained from our study has great promise and immediate translational values. Anti-SIAH-based small molecule inhibitors may aid in expanding our arsenal of novel anticancer therapies. By attacking the oncogenic ERBB/K-RAS/B-RAF pathway using multi-pronged synergistic inhibitions at upstream (EGFR/HER2 membrane receptors), midstream (K-RAS/B-RAF/MEK/mTOR) and downstream (SIAH E3 ligase) signaling modules in parallel, we will be in a position to control the late-stage, relapsed and metastatic human cancers. If successful, we hope to develop anti-SIAH-based therapy and translate our findings to the cancer clinics to treat cancer patients with metastatic diseases in the near future. Citation Format: Minglei Bian, Yang Liao, Vasilena Zheleva, Xiaofei Gao, Zena M. Urban, Monicah M. Njogu, Justin J. Odanga, Andrew J. Isbell, Rebecca L. Schmidt, Rie Takahashi, Roger R. Perry, Richard A. Hoefer, Thomas C. Smyrk, Gloria M. Petersen, Amy H. Tang. Attacking the most downstream “gatekeeper” signaling module in the oncogenic ERBB/K-RAS signaling pathway to block tumorigenesis and metastasis in human cancer. [abstract]. In: Proceedings of the Third AACR International Conference on Frontiers in Basic Cancer Research; Sep 18-22, 2013; National Harbor, MD. Philadelphia (PA): AACR; Cancer Res 2013;73(19 Suppl):Abstract nr C62.

Abstract Hepatocellular cancer (HCC) is a highly treatment-refractory cancer and is also highly resistant to adverse cellular stress. Although cell behavior can be modulated by noncoding RNAs (ncRNA) within extracellular vesicles (EV), the contributions of long noncoding RNAs (lncRNAs) are largely unknown. To this end, the involvement and functional roles of lncRNAs contained within EVs during chemotherapeutic stress in human HCC were determined. Expression profiling identified a subset of lncRNAs that were enriched in tumor cell–derived vesicles released from two different cell lines. Of these, lincRNA-VLDLR (linc-VLDLR) was significantly upregulated in malignant hepatocytes. Exposure of HCC cells to diverse anticancer agents such as sorafenib, camptothecin, and doxorubicin increased linc-VLDLR expression in cells as well as within EVs released from these cells. Incubation with EVs reduced chemotherapy-induced cell death and also increased linc-VLDLR expression in recipient cells. RNAi-mediated knockdown of linc-VLDLR decreased cell viability and abrogated cell-cycle progression. Moreover, knockdown of VLDLR reduced expression of ABCG2 (ATP-binding cassette, subfamily G member 2), whereas overexpression of this protein reduced the effects of VLDLR knockdown on sorafenib-induced cell death. Here, linc-VLDLR is identified as an EV-enriched lncRNA that contributes to cellular stress responses. Implications: These findings provide new insight into the role of EVs and demonstrate the capacity of lncRNAs to mediate chemotherapeutic stress response in HCC. Mol Cancer Res; 12(10); 1377–87. ©2014 AACR.

SummaryTestosterone (T) impacts luteinizing hormone (LH) secretion through negative feedback via the androgen receptor (AR) in the hypothalamo‐pituitary system. An untested postulate is that increasing body mass index (BMI), abdominal visceral fat (AVF) or total abdominal fat (TAF) with ageing decreases LH secretion by heightening T negative feedback via AR. This hypothesis was tested in a prospective, randomized double‐blind cross‐over study of 19 healthy men comparing the effects of flutamide, a selective non‐steroidal AR antagonist and placebo administration on basal and pulsatile LH secretion as a function of age and obesity measures. To this end, serum levels of 2‐hydroxyflutamide (2‐OHF), a major active flutamide metabolite, were measured by mass spectrometry, and AVF/TAF quantified by abdominal computerized tomography. Statistical analysis showed that antiandrogen administration elevated 6‐h mean LH concentrations to 5.4 ± 1.3 IU/L compared with 3.3 ± 1.2 IU/L for placebo (p < 10−3), and total T by 35% (p < 10−4). The LH‐T concentration product doubled (p < 10−8). According to deconvolution analysis, flutamide exposure increased total LH secretion (p < 10−3) and pulsatile LH secretion (p = 0.0077), along with LH pulse frequency (p = 0.019). Despite feedback inhibition, the LH‐T product declined as a linear function of AVF (p = 0.021) and TAF (p = 0.017). This was explained by the fact that higher BMI was associated with lower 2‐OHF concentrations (R = −0.562, p = 0.012). In contrast, age was associated with less pulsatile LH secretion (R = −0.567, p = 0.011) even when LH responses were normalized to antiantrogen levels. In conclusion, increased AVF, TAF and BMI predict decreased LH and flutamide blood levels, whereas older age is marked by impaired stimulation of pulsatile LH secretion even when normalized for antiandrogen levels, suggesting different mechanisms of regulation by adiposity and age.

The microRNAs (miRNAs) are small noncoding RNAs that are potent regulators of gene expression and can regulate several diverse biological functions. This minireview provides an overview of recent studies that have examined the role and involvement of miRNAs in cholangiocarcinomas. These studies provide evidence for deregulated expression of miRNA and are providing new insights into the potential contribution of these in the pathogenesis of cholangiocarcinoma.