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Background: The scarcity of tissues from racial and ethnic minorities at biobanks poses a scientific constraint to research addressing health disparities in minority populations., Methods: To address this gap, the Minority Biospecimen/Biobanking Geographic Management Program for region 3 (BMaP-3) established a working infrastructure for a "biobanking" hub in the southeastern United States and Puerto Rico. Herein we describe the steps taken to build this infrastructure, evaluate the feasibility of collecting formalin-fixed, paraffin-embedded tissue blocks and associated data from a single cancer type (breast), and create a web-based database and tissue microarrays (TMAs)., Results: Cancer registry data from 6 partner institutions were collected, representing 12,408 entries from 8,279 unique patients with breast cancer (years 2001-2011). Data were harmonized and merged, and deidentified information was made available online. A TMA was constructed from formalin-fixed, paraffin-embedded samples of invasive ductal carcinoma (IDC) representing 427 patients with breast cancer (147 African Americans, 168 Hispanics, and 112 non-Hispanic whites) and was annotated according to biomarker status and race/ethnicity. Biomarker analysis of the TMA was consistent with the literature., Conclusions: Contributions from participating institutions have facilitated a robust research tool. TMAs of IDC have now been released for 5 projects at 5 different institutions.

Background: Lung cancer is the most common cancer in the world. In addition to the geographical and sex-specific differences in the incidence, mortality, and survival rates of lung cancer, growing evidence suggests that racial and ethnic differences exist., Methods: We reviewed published data related to racial and ethnic differences in lung cancer., Results: Current knowledge and substantive findings related to racial and ethnic differences in lung cancer were summarized, focusing on incidence, mortality, survival, cigarette smoking, prevention and early detection, and genomics. Systems-level and health care professional-related issues likely to contribute to specific racial and ethnic health disparities were also reviewed to provide possible suggestions for future strategies to reduce the disproportionate burden of lung cancer., Conclusions: Although lung carcinogenesis is a multifactorial process driven by exogenous exposures, genetic variations, and an accumulation of somatic genetic events, it appears to have racial and ethnic differences that in turn impact the observed epidemiological differences in rates of incidence, mortality, and survival.

In preparation for the development of a rapid tissue donation (RTD) programme, we surveyed healthcare providers (HCPs) in our institution about knowledge and attitudes related to RTD with lung cancer patients. A 31-item web based survey was developed collecting data on demographics, knowledge and attitudes about RTD. The survey contained three items measuring participants' knowledge about RTD, five items assessing attitudes towards RTD recruitment and six items assessing HCPs' level of agreement with factors influencing decisions to discuss RTD. Response options were presented on a 5-point Likert scale. Ninety-one HCPs participated in the study. 66% indicated they had never heard of RTD prior to the survey, 78% rated knowledge of RTD as none or limited and 95.6% reported not having ethical or religious concerns about discussing RTD with patients. The majority were either not comfortable (17.8%) or not sure if they felt comfortable discussing RTD with cancer patients (42.2%). 56.1% indicated their knowledge of RTD would play an integral role in their decision to discuss RTD with patients. 71.4% reported concerns with RTD discussion and the emotional state of the patient. Physicians and nurses play an important role in initiating conversations about recruitment and donation to research that can ultimately influence uptake. Increasing HCP knowledge about RTD is a necessary step towards building an RTD programme. Our study provides important information about characteristics associated with low levels of knowledge and practice related to RTD where additional education and training may be warranted.

The disproportionate burden of cancer among U.S. Hispanics is well documented. Historically, epidemiologic data on U.S. Hispanics and cancer have aggregated all Hispanics as one homogeneous group without appreciating the diversity of this population with regard to nativity (nationality/geographic origin). The authors report on the initial efforts of a collaborative academic institutional partnership between a minority-serving institution and a National Cancer Institute-designated cancer center to address cancer health disparities in two Hispanic communities in Puerto Rico and Florida. This article outlines the joint Outreach Program's initial collaborative strategies and activities in community outreach, cancer education, and research that mutually benefit both the Ponce (Puerto Rico) and Tampa (Florida) Hispanic communities. This partnership program used innovative multipronged community-engagement strategies in the two communities to reduce cancer health disparities. Specific projects and lessons learned from three outreach/cancer education projects and two pilot research projects are discussed. The challenges of balancing service and research agendas in communities with disparate levels of resources and infrastructure are summarized to inform future initiatives in this partnership, as well as serve as an example for similar minority-serving institution/cancer center partnerships to reduce cancer health disparities.

Three members of Gab family docking proteins, Gab1, Gab2 and Gab3, have been identified in humans. Previous studies have found that the hepatocyte growth factor preferentially utilizes Gab1 for signalling, whereas Bcr-Abl selectively signals through Gab2. Gab1-SHP2 interaction has been shown to mediate ERK (extracellular-signal-regulated kinase) activation by EGF (epidermal growth factor). However, it was unclear whether EGF selectively utilizes Gab1 for signalling to ERK and whether Gab2 is dispensable in cells where Gab1 and Gab2 are co-expressed. Using T47D and MCF-7 human breast carcinoma cells that express endogenous Gab1 and Gab2, we examined the role of these docking proteins in EGF-induced ERK activation. It was found that EGF induced a similar amount of SHP2-Gab1 and SHP2-Gab2 complexes. Expression of either SHP2-binding defective Gab1 or Gab2 mutant blocked EGF-induced ERK activation. Down-regulation of either Gab1 or Gab2 by siRNAs (small interfering RNAs) effectively inhibited the EGF-stimulated ERK activation pathway and cell migration. Interestingly, the inhibitory effect of Gab1 siRNA could be rescued not only by expression of an exogenous mouse Gab1 but also by an exogenous human Gab2 and vice versa, but not by IRS1 (insulin receptor substrate 1). These results reveal that Gab2 plays a pivotal role in the EGF-induced ERK activation pathway and that it can complement the function of Gab1 in the EGF signalling pathway. Furthermore, Gab1 and Gab2 are critical signalling threshold proteins for ERK activation by EGF.

Several small GTPases of the Ras superfamily have been shown to antagonize TGFbeta signaling in human tumor cell lines. Some of these GTPases are post-translationally modified by farnesylation, a lipid modification catalyzed by farnesyltransferase and required for the proteins to attach to membranes and to function. In this study, we investigated the effect of the farnesyltransferase inhibitor FTI-277 on TGFbeta-regulated cell growth and transcription. Treatment of the human pancreatic tumor cell line, Panc-1, with FTI-277 enhanced the ability of TGFbeta to inhibit both anchorage-dependent and -independent tumor cell growth. FTI-277 also enhanced the ability of TGFbeta to induce transcription, as measured by p3TP-lux reporter activity and collagen synthesis. The enhancement of TGFbeta responses by FTI-277 correlated with the stimulation of transcription and protein expression of type II TGFbeta receptor (TbetaRII). Consequently, FTI-277-treated cells exhibited a higher level of TGFbeta binding to its receptor. Thus, inhibition of protein farnesylation stimulates TbetaRII expression, which leads to increased TGFbeta receptor binding and signaling as well as inhibition of tumor cell growth and transformation.

Objective: To evaluate the factors involved in bone remodeling and wound healing that may be altered by radiation therapy., Design: A prospective, controlled study of biochemical activity in vitro., Subjects: MC3T3-E1 mouse osteoblasts., Interventions: Cells were irradiated at 0, 2, 4, or 6 Gy. Specimens were harvested at 1, 7, 14, 28, and 42 days following irradiation for immunohistochemical analysis of transforming growth factor beta(1) expression and transforming growth factor beta(1) type I and II receptor expression. Collagen production was measured at 1, 7, 28, 35, and 49 days after irradiation. The effects of dexamethasone on collagen production and cell proliferation were also examined., Results: Irradiated cells demonstrated decreased cell proliferation and a dose-dependent, sustained reduction in collagen production when compared with control cells. An increase in transforming growth factor beta(1) type I and II receptor expression was noted in irradiated cells when compared with controls., Conclusion: Radiation-induced alterations of factors related to bone remodeling and wound healing have a potential role in the pathogenesis of osteoradionecrosis.

Objective: Resistance to transforming growth factor (TGF)-beta-mediated cell growth inhibition is a well-known pathogenic mechanism in epithelial neoplasia. TGF-beta signaling requires normal function of downstream mediators such as TGF-beta receptors (TbetaRs) and Smad proteins. The goal of this study is to investigate the expression of components of the TGF-beta signaling pathway in follicular tumors of the thyroid., Study Design: Twenty follicular thyroid neoplasms were classified as adenomas (11) or minimally invasive follicular carcinomas (9) according to current pathological criteria. Protein expression was evaluated to identify differences between benign and malignant tumors that could be used as an adjunct to histopathological analysis., Methods: Paraffin-embedded tissue sections containing tumor and adjacent nonneoplastic parenchyma were analyzed by immunohistochemistry for the expression of TbetaR type II (TbetaR-II) and Smad2, Smad4, Smad6, and Smad7. Expression of each protein in the tumor was compared with that of the corresponding adjacent nonneoplastic thyroid parenchyma., Results: TbetaR-II expression was lost in 78% of the carcinomas. In the remaining 22%, TbetaR-II was preserved but Smad2 expression was lost. In all conventional adenomas, however, TbetaR-II expression was maintained. Furthermore, all tumors with normal expression of all proteins were adenomas., Conclusions: Downregulation of TbetaR-II is a consistent abnormality in follicular carcinomas and can be used to differentiate minimally invasive carcinomas from adenomas. Also, downregulation of Smad proteins is another mechanism by which carcinomas can become independent from TGF-beta-mediated growth inhibition.

In African trypanosomes the requirements for glucose and its metabolism vary in different stages of the life cycle. Here we present evidence that cultured procyclic trypanosomes of Trypanosoma brucei rhodesiense uptake glucose against a concentration gradient in a time and dose-dependent manner. Moreover, glucose transport is completely inhibited by the sulphydryl inhibitor N-ethylmaleimide, suggesting the presence of a protein moiety as the carrier molecule. Comparison of glucose uptake in bloodstream and procyclic trypanosomes point to the possibility that different transporters may function in the 2 developmental stages. Glucose uptake by bloodstream trypanosomes requires Na+ ions and is inhibited by phlorizin, an inhibitor of Na(+)-dependent glucose transporters in mammalian cells. Conversely, procyclic trypanosomes transport glucose in a Na(+)-dependent manner, and transport is not affected by phlorizin. Finally, the putative procyclic glucose transporter has a higher affinity for glucose (apparent Km 23 microM) than the bloodstream carrier (apparent Km 237 microM).