The NCI Center to Reduce Cancer Health Disparities: Moving Forward to Eliminate Cancer Health Disparities and Diversify the Cancer Biomedical Workforce.

The National Cancer Institute's (NCI) Center to Reduce Cancer Health Disparities (CRCHD) was established in 2001 with the purpose of confronting and eliminating cancer health disparities, while increasing workforce diversity in cancer research. Over the last two decades, CRCHD has generated a broad range of research, training, and community outreach activities to address these overarching goals through a variety of programs including the Continuing Umbrella of Research Experiences (CURE), Partnerships to Advance Cancer Health Equity (PACHE), Special Populations Networks (SPN), Community Networks Program (CNP), CNP Centers (CNPC), and Patient Navigation Research Program (PNRP). CRCHD, through its CURE and now its Intramural CURE (iCURE) programs, has been fully dedicated to training the next generation of competitive researchers from backgrounds typically underrepresented in the cancer and cancer health disparities research fields. Today, CRCHD leads NCI's efforts in supporting research training and career development experiences beginning as early as middle school and continuing through to tenured track appointments. CRCHD has also developed a robust basic research focus in cancer disparities, which has recently expanded into translational disparities research and the generation of novel, authenticated animal models appropriate for advancing disparities research investigations. Additionally, CRCHD has fostered an integrated networks infrastructure to complement and support its disparities research and diversity training efforts, as well as provide cancer education and outreach among racially and ethnically diverse and medically underserved communities. Moving forward, the CRCHD will continue its steadfast efforts to move us closer to the day when diversity is a given and disparities no longer exist.

Screen to Save: Results from NCI's Colorectal Cancer Outreach and Screening Initiative to Promote Awareness and Knowledge of Colorectal Cancer in Racial/Ethnic and Rural Populations.

BACKGROUND: The Center to Reduce Cancer Health Disparities (CRCHD), NCI, implemented Screen to Save, NCI's Colorectal Cancer Outreach and Screening Initiative to promote awareness and knowledge of colorectal cancer in racial/ethnic and rural populations. METHODS: The initiative was implemented through CRCHD's National Outreach Network (NON). NON is a national network of Community Health Educators (CHE), aligned with NCI-designated Cancer Centers across the nation. In phases I and II, the CHEs focused on the dissemination of cancer-related information and implementation of evidence-based educational outreach. RESULTS: In total, 3,183 pre/post surveys were obtained from male and female participants, ages 50 to 74 years, during the 347 educational events held in phase I. Results demonstrated all racial/ethnic groups had an increase in colorectal cancer-related knowledge, and each group strongly agreed that the educational event increased the likelihood that they would engage in colorectal cancer-related healthful behaviors (e.g., obtain colorectal cancer screening and increase physical activity). For phase II, Connections to Care, event participants were linked to screening. Eighty-two percent of the participants who obtained colorectal cancer screening during the 3-month follow-up period obtained their screening results. CONCLUSIONS: These results suggest that culturally tailored, standardized educational messaging and data collection tools are key change agents that can serve to inform the effectiveness of educational outreach to advance awareness and knowledge of colorectal cancer. IMPACT: Future initiatives should focus on large-scale national efforts to elucidate effective models of connections to care, related to colorectal cancer screening, follow-up, and treatments that are modifiable to meet community needs.

Education on cancer risk assessment and genetic counseling to address cancer health disparities among racial/ethnic groups and rural populations: Implementing culturally tailored outreach through community health educators.

While significant progress is being made in cancer prevention and treatment, opportunity exists to make a difference for populations bearing an uneven burden of the disease. Research indicates that increased inherited risk and more-aggressive forms of cancer among underserved racial/ethnic (R/E) groups (e.g., African American/Black, American Indian/Alaska Native, Asian, Hispanic/Latino, and Native Hawaiian/Other Pacific Islander) and rural populations may explain the cancer incidence and mortality disparities these populations experience. These racial and ethnic (R/E) categories reflect the standard naming convention for the classification of federal data on race and ethnicity. One method by which progress can be made for these underserved populations is to expand knowledge of, access to, and uptake of two existing and impactful preventive oncology tools-cancer screening and genetic counseling and risk assessment (GCRA). Individuals from these populations who have cancer may benefit by learning about treatment options, risk projections for secondary cancers, and clinical trial participation. Effecting change in community beliefs and behaviors regarding these preventive tools and yielding the aforementioned benefits will see greater success if shepherded by individuals accepted and trusted in the respective communities. This was the charge taken on and embraced by Community Health Educators in the National Cancer Institute (NCI) Center to Reduce Cancer Health Disparities' (CRCHD) National Outreach Network (NON) and U54 Comprehensive Partnerships to Advance Cancer Health Equity (CPACHE) programs. The NCI CRCHD integrated into the work of these CHEs an emphasis on cancer genetic education. As part of their undertaking, NON and CPACHE CHEs detail education and outreach strategies that may be helpful to increase GCRA awareness and uptake in R/E groups and rural populations and, in turn, bring positive change for those with or at risk for heritable cancers.

The Continuing Umbrella of Research Experiences (CURE): a model for training underserved scientists in cancer research.

Mentoring is a critical aspect of research and training; and the adoption of a successful mentoring model for guiding researchers through the educational pipeline is lacking. The Continuing Umbrella of Research Experiences (CURE) program was established in the Comprehensive Minority Biomedical Branch; which is part of the National Cancer Institute. This program offers unique training and career development opportunities to enhance diversity in cancer research. The CURE initiative focuses on broadening the cadre of underserved investigators engaging in cancer research. CURE begins with high school students and fosters scientific, academic and research excellence throughout the trainee's educational progression. The program supports students throughout the entirety of their training career. During this period, the trainee matures into a competitive early stage investigator; capable of securing advanced research project funding in academic and industry workforces. Thus, the CURE program provides a comprehensive vehicle for training and reinforces the critical mass of underserved investigators conducting cancer research.

Macrophage response to methacrylate conversion using a gradient approach.

Incomplete conversion, an ongoing challenge facing photopolymerized methacrylate-based polymers, affects leachables as well as the resulting polymer network. As novel polymers and composites are developed, methods to efficiently screen cell response to these materials and their properties, including conversion, are needed. In this study, an in vitro screening methodology was developed to assess cells cultured directly on cross-linked polymer networks. A gradient in methacrylate double bond conversion was used to increase the experimental throughput. A substrate of 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy)phenyl] propane (BisGMA) and triethylene glycol dimethacrylate (TEGDMA) was prepared with a conversion ranging from 43.0% to 61.2%. Substrates aged for 7 days had no significant differences in surface roughness or hydrophilicity as a function of conversion. Leachables were detectable for at least 7 days using UV absorption, but their global cytotoxicity was insignificant after 5 days of aging. Thus, RAW 264.7 macrophage-like cells were cultured on aged substrates to evaluate the cell response to conversion, with possible contributions from the polymer network and local leachables. Conversions of 45% and 50% decreased viability (via calcein/ethidium staining) and increased apoptosis (via annexin-V staining). No significant changes (p>0.05) in tumor necrosis factor-alpha and interleukin-1beta gene expression, as measured by quantitative, real-time reverse transcription-polymerase chain reaction, were seen as conversion increased. Thus, conversions greater than 50% are recommended for equimolar BisGMA/TEGDMA. The ability to distinguish cell response as a function of conversion is useful as an initial biological screening platform to optimize dental polymers.

Encapsulated chondrocyte response in a pulsatile flow bioreactor.

We have developed a bioreactor-based millifluidic technique that allows for dynamic culture conditions and measurement of the fluid flow impinging upon a three-dimensional tissue engineering scaffold. Chondrocytes in scaffolds have been shown to require mechanical stimulation to produce an extracellular matrix that resembles native cartilage. This study investigates the effect of pulsatile flow on chondrocyte response in a model poly(ethylene glycol) dimethacrylate hydrogel. Bovine chondrocytes were encapsulated in the hydrogel and cultured for 7, 14 and 21 days at pulsatile flow frequencies of 0.5 Hz (15ml/min) and 1.5Hz (17ml/min). The scaffolds cultured under dynamic conditions were compared to those cultured under static (non-flow) conditions. Quantitative real-time reverse transcription polymerase chain reaction was used to quantify collagen type I, collagen type II and aggrecan gene copy numbers as markers for chondrocyte phenotypic expression. Histological sections stained with hematoxylin & eosin, and Alcian blue confirmed chondrocyte morphology and matrix formation. Interestingly, regulation of the collagen type II gene was particularly sensitive to the flow conditions. The understanding of the cell response to encapsulation and flow could be used to identify the appropriate culture conditions necessary to design and develop hydrogel carriers to promote the formation of extracellular matrix as well as to further our knowledge of chondrocyte mechanobiology.

Evaluation of the anterior cruciate ligament, medial collateral ligament, achilles tendon and patellar tendon as cell sources for tissue-engineered ligament.

This study investigated four different connective tissue cell types to determine which cell type should be the source for seeding a tissue-engineered anterior cruciate ligament (ACL) replacement. Cells derived from the ACL, medial collateral ligament (MCL), achilles tendon (AT), and patellar tendon (PT) of New Zealand White rabbits were isolated and cultured. Each cell type was cultured in vitro after seeding on three-dimensional (3-D) braided polymer scaffolds and on tissue culture polystyrene that served as a control. Samples were evaluated and compared for their morphology, proliferation, and gene expression of fibronectin, type I and type III collagen. Scanning electron microscopy (SEM) photomicrographs verified cell attachment of all four types of connective tissue fibroblasts to the scaffolds. Preliminary results comparing proliferation indicate that cells obtained from the PT and AT have the fastest proliferation. Whereas gene expression of the phenotypic markers measured using real-time reverse transcription polymerase chain reaction (RT-PCR) indicates ACL cells have the highest gene expression for the matrix markers. This leads to the question of which cell type should be the cell source for tissue-engineering of ligament, the highly proliferating cells or the differentiated matrix producing cells. This study would suggest that ACL differentiated matrix producing cells are the most suitable cells for further study and development of a tissue-engineered ligament.

Cellular response to phase-separated blends of tyrosine-derived polycarbonates.

Two-dimensional thin films consisting of homopolymer and discrete compositional blends of tyrosine-derived polycarbonates were prepared and characterized in an effort to elucidate the nature of different cell responses that were measured in vitro. The structurally similar blends were found to phase separate after annealing with domain sizes dependent on the overall composition. The thin polymer films were characterized with the use of atomic force microscopy (AFM), water contact angles, and time-of-flight secondary ion mass spectrometry (TOF-SIMS) and significant changes in roughness were measured following the annealing process. Genetic expression profiles of interleukin-1beta and fibronectin in MC3T3-E1 osteoblasts and RAW 264.7 murine macrophages were measured at several time points, demonstrating the time and composition-dependent nature of the cell responses. Real-time reverse transcriptase polymerase chain reaction (RT-PCR) depicted upregulation of the fibronectin gene copy numbers in each of the blends relative to the homopolymers. Moreover, the interleukin-1beta expression profile was found to be compositionally dependent. The data suggest strongly that optimal composition and processing conditions can significantly affect the acute inflammatory and extracellular matrix production responses.

Development of a model for the representation of nanotechnology-specific terminology.

Nanotechnology is an important, rapidly-evolving, multidisciplinary field. The tremendous growth in this area necessitates the establishment of a common, open-source terminology to support the diverse biomedical applications of nanotechnology. Currently, the consensus process to define and categorize conceptual entities pertaining to nanotechnology is in a rudimentary stage. We have constructed a nanotechnology-specific conceptual hierarchy that can be utilized by end users to retrieve accurate, controlled terminology regarding emerging nanotechnology and corresponding clinical applications.

The quantification of cellular viability and inflammatory response to stainless steel alloys.

The biocompatibility of metallic alloys is critical to the success of many orthopedic therapies. Corrosion resistance and the immune response of the body to wear debris products ultimately determine the performance of these devices. The establishment of quantitative tests of biocompatibility is an important issue for biomaterials development. We have developed an in vitro model to measure the pro-inflammatory cytokine production and in this study investigated the cellular responses induced by nitrogenated and 316L stainless steel alloys in both particulate and solid form. We utilized a murine macrophage cell line, RAW 264.7, to characterize and compare the mRNA profiles of TNF-alpha and IL-1beta in these cells using real time-polymerase chain reaction (RT-PCR). Fluorescence microscopy and flow cytometry were used to probe the viability of the population and to examine the apoptotic pathway. The goals of this work were to develop improved measurement methods for the quantification of cellular inflammatory responses to biomaterials and to obtain data that leads to an enhanced understanding of the ways in which the body responds to biomaterials. Using these techniques, we observed evidence for an association between the upregulation of IL-1beta and reversible apoptosis, and the upregulation of TNF-alpha and irreversible apoptosis.

Peptide-derivatized shell-cross-linked nanoparticles. 2. Biocompatibility evaluation.

The conjugation of the protein transduction domain (PTD) from the HIV-1 Tat protein to shell cross-linked (SCK) nanoparticles is a method to facilitate cell surface binding and transduction. In the previous report, the preparation, derivatization, and characterization of peptide-functionalized SCK nanoparticles were reported in detail. Following assembly, the constructs were evaluated in vitro and in vivo to obtain a preliminary biocompatibility assessment. The effects of SCK exposure on cell viability were evaluated using a metabolic 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) and a fluorescent apoptosis assay. Furthermore, stages of apoptosis were quantified by flow cytometry. Although higher levels of peptide functionalization resulted in decreased metabolic function as measured by MTT assay, significant apoptosis was not observed below 500 mg/L for all the samples. To evaluate the potential immunogenic response of the peptide-derivatized constructs, a real-time polymerase chain reaction (RT-PCR) system that allows for the in vitro analysis and quantification of the cellular inflammatory responses tumor necrosis factor alpha (TNF-alpha) and interleukin-1 beta (IL1-beta) was utilized. The inflammatory response to the peptide-functionalized SCK nanoparticles as measured by RT-PCR show statistically significant increases in the levels of both TNF-alpha and IL1-beta relative to tissue culture polystyrene (TCPS). However, the measured cytokine levels did not preclude the further testing of SCKs in an in vivo mouse immunization protocol. In this limited assay, measured increases in immunoglobulin G (IgG) concentration in the sera were minimal with no specific interactions being isolated, and more importantly, none of the mice (>50) subjected to the three 100 microg immunization protocol have died. Additionally, no gross morphological changes were observed in postmortem organ histology examinations.

Quantification of inflammatory cellular responses using real-time polymerase chain reaction.

The introduction of tissue engineering strategies for the repair and replacement of human body components extends the application and importance of biomaterials. Implanted biomaterials frequently evoke inflammatory responses that are complex and not well understood at present. The goals of this work were to develop improved measurement methods for the quantification of cellular inflammatory responses to biomaterials and obtain data that lead to an enhanced understanding of the ways in which the body responds to the introduction of biomaterials. To evaluate the biocompatibility of materials, we established a system that allows for the analysis and quantitation of cellular inflammatory responses in vitro. In this study, the inflammatory responses of murine macrophages (RAW 264.7) were analyzed. The cells were incubated with polymethylmethacrylate (PMMA) microspheres in the presence and absence of lipopolysaccharide (LPS) at 8 and 18 h. The analysis of the genetic material obtained from the cells was quantitated using real-time reverse transcription polymerase chain reaction (RT-PCR). The cell populations treated with LPS or PMMA microspheres singly resulted in an elevation of cytokine levels compared to the untreated control. LPS resulted in a 258-fold increase, while PMMA resulted in an 87.9-fold increase at 8 h. RAW 264.7 cells incubated with LPS and PMMA particles demonstrated a synergistic effect by producing a marked increase in the level of cytokine expression, 336-fold greater than that of the untreated control at 8 h. Fluorescence microscopy studies that assessed cellular viability were also performed and are consistent with the RT-PCR results.