Mack T. Ruffin

Dose escalation of a curcuminoid formulation

BackgroundCurcumin is the major yellow pigment extracted from turmeric, a commonly-used spice in India and Southeast Asia that has broad anticarcinogenic and cancer chemopreventive potential. However, few systematic studies of curcumins pharmacology and toxicology in humans have been performed.MethodsA dose escalation study was conducted to determine the maximum tolerated dose and safety of a single dose of standardized powder extract, uniformly milled curcumin (C3Complex™, Sabinsa Corporation). Healthy volunteers were administered escalating doses from 500 to 12,000 mg.ResultsSeven of twenty-four subjects (30%) experienced only minimal toxicity that did not appear to be dose-related. No curcumin was detected in the serum of subjects administered 500, 1,000, 2,000, 4,000, 6,000 or 8,000 mg. Low levels of curcumin were detected in two subjects administered 10,000 or 12,000 mg.ConclusionThe tolerance of curcumin in high single oral doses appears to be excellent. Given that achieving systemic bioavailability of curcumin or its metabolites may not be essential for colorectal cancer chemoprevention, these findings warrant further investigation for its utility as a long-term chemopreventive agent.

Pharmacokinetics of Curcumin Conjugate Metabolites in Healthy Human Subjects

Background: Curcumin is a polyphenol, found in the spice turmeric, that has promising anticancer properties, but previous studies suggest that absorption of curcumin may be limited. Methods: This study examined the pharmacokinetics of a curcumin preparation in healthy human volunteers 0.25 to 72 h after a single oral dose. Curcumin was administered at doses of 10 g (n = 6) and 12 g (n = 6). Subjects were randomly allocated to dose level for a total of six subjects at each dose level. Serum samples were assayed for free curcumin, for its glucuronide, and for its sulfate conjugate. The data were fit to a one-compartment absorption and elimination model. Results: Using a high-performance liquid chromatography assay with a limit of detection of 50 ng/mL, only one subject had detectable free curcumin at any of the 14 time points assayed, but curcumin glucuronides and sulfates were detected in all subjects. Based on the pharmacokinetic model, the area under the curve for the 10 and 12 g doses was estimated (mean ± SE) to be 35.33 ± 3.78 and 26.57 ± 2.97 μg/mL × h, respectively, whereas Cmax was 2.30 ± 0.26 and 1.73 ± 0.19 μg/mL. The Tmax and t1/2 were estimated to be 3.29 ± 0.43 and 6.77 ± 0.83 h. The ratio of glucuronide to sulfate was 1.92:1. The curcumin conjugates were present as either glucuronide or sulfate, not mixed conjugates. Conclusion: Curcumin is absorbed after oral dosing in humans and can be detected as glucuronide and sulfate conjugates in plasma. (Cancer Epidemiol Biomarkers Prev 2008;17(6):1411–7)

Characteristics of a productive research environment: literature review

What environmental factors stimulate and maintain research productivity? To answer this question, the authors conducted an extensive review of articles and books on research productivity published from the mid-1960s through 1990. This review revealed that a consistent set of 12 characteristics was found in research-conducive environments: (1) clear goals that serve a coordinating function, (2) research emphasis, (3) distinctive culture, (4) positive group climate, (5) assertive participative governance, (6) decentralized organization, (7) frequent communication, (8) accessible resources, particularly human, (9) sufficient size, age, and diversity of the research group, (10) appropriate rewards, (11) concentration on recruitment and selection, and (12) leadership with research expertise and skill in both initiating appropriate organizational structure and using participatory management practices. Some of these characteristics are not surprising, although some findings were unexpected, such as that participative governance correlated consistently with research productivity. The differential impact of each of these 12 characteristics is unclear. It is clear, however, that the leader has a disproportionate impact through his or her influence on all of the other characteristics. Yet, an overarching feature of these characteristics is their interdependency. These factors do not operate in research groups as isolated characteristics. Rather, they are like fine threads of a whole fabric: individual, yet when interwoven, providing a strong, supportive, and stimulating backdrop for the researcher. The authors conclude that while at a distance the productive research enterprise looks like a highly robust entity, upon closer inspection it is revealed to be a delicate structure highly dependent on the existence and effective working of numerous individual, organizational, and leadership characteristics.

Understanding the Reasons Why Mothers Do or Do Not Have Their Adolescent Daughters Vaccinated Against Human Papillomavirus

PURPOSE The objective of this study was to compare the reasons why mothers do or do not have their adolescent daughters vaccinated against HPV. METHODS Mothers of vaccinated and unvaccinated 11- to 17-year-old girls seen during preventive care visits in outpatient family medicine or pediatric clinics underwent an audiotaped structured telephone interview that used open-ended questions to assess the reasons underlying maternal decisions about HPV vaccination. Qualitative methods categorized maternal responses into themes. RESULTS Interviews of 52 mothers (19 declining vaccination, 33 accepting) identified several distinct factors underlying their decisions about HPV vaccination. Lack of knowledge about HPV, age-related concerns, and low perceived risk of infection were commonly cited reasons for declining vaccination. Desire to prevent illness, physician recommendation, and a high perceived risk of infection were commonly identified motivating factors. Both groups of mothers had significant concerns about vaccine safety. Locus of control (e.g., mother or daughter) of health-related decisions arose as a novel factor influencing this decision that had not been previously described in the context of HPV vaccination. CONCLUSIONS Addressing safety concerns, educating parents about the age-specific risk of HPV infection, and promoting strong physician recommendation for vaccination may be the most useful targets for future interventions to increase HPV vaccine utilization.

The Human Gut Microbiome as a Screening Tool for Colorectal Cancer

Recent studies have suggested that the gut microbiome may be an important factor in the development of colorectal cancer. Abnormalities in the gut microbiome have been reported in patients with colorectal cancer; however, this microbial community has not been explored as a potential screen for early-stage disease. We characterized the gut microbiome in patients from three clinical groups representing the stages of colorectal cancer development: healthy, adenoma, and carcinoma. Analysis of the gut microbiome from stool samples revealed both an enrichment and depletion of several bacterial populations associated with adenomas and carcinomas. Combined with known clinical risk factors of colorectal cancer (e.g., BMI, age, race), data from the gut microbiome significantly improved the ability to differentiate between healthy, adenoma, and carcinoma clinical groups relative to risk factors alone. Using Bayesian methods, we determined that using gut microbiome data as a screening tool improved the pretest to posttest probability of adenoma more than 50-fold. For example, the pretest probability in a 65-year-old was 0.17% and, after using the microbiome data, this increased to 10.67% (1 in 9 chance of having an adenoma). Taken together, the results of our study demonstrate the feasibility of using the composition of the gut microbiome to detect the presence of precancerous and cancerous lesions. Furthermore, these results support the need for more cross-sectional studies with diverse populations and linkage to other stool markers, dietary data, and personal health information. Cancer Prev Res; 7(11); 1112–21. ©2014 AACR.

Plasma glycoprotein profiling for colorectal cancer biomarker identification by lectin glycoarray and lectin blot

Colorectal cancer (CRC) remains a major worldwide cause of cancer-related morbidity and mortality largely due to the insidious onset of the disease. The current clinical procedures utilized for disease diagnosis are invasive, unpleasant, and inconvenient; hence, the need for simple blood tests that could be used for the early detection of CRC. In this work, we have developed methods for glycoproteomics analysis to identify plasma markers with utility to assist in the detection of colorectal cancer (CRC). Following immunodepletion of the most abundant plasma proteins, the plasma N -linked glycoproteins were enriched using lectin affinity chromatography and subsequently further separated by nonporous silica reversed-phase (NPS-RP)-HPLC. Individual RP-HPLC fractions were printed on nitrocellulose coated slides which were then probed with lectins to determine glycan patterns in plasma samples from 9 normal, 5 adenoma, and 6 colorectal cancer patients. Statistical tools, including principal component analysis, hierarchical clustering, and Z-statistics analysis, were employed to identify distinctive glycosylation patterns. Patients diagnosed with colorectal cancer or adenomas were shown to have dramatically higher levels of sialylation and fucosylation as compared to normal controls. Plasma glycoproteins with aberrant glycosylation were identified by nano-LC-MS/MS, while a lectin blotting methodology was used to validate proteins with significantly altered glycosylation as a function of cancer progression. The potential markers identified in this study for diagnosis to distinguish colorectal cancer from adenoma and normal include elevated sialylation and fucosylation in complement C3, histidine-rich glycoprotein, and kininogen-1. These potential markers of colorectal cancer were subsequently validated by lectin blotting in an independent set of plasma samples obtained from 10 CRC patients, 10 patients with adenomas, and 10 normal subjects. These results demonstrate the utility of this strategy for the identification of N -linked glycan patterns as potential markers of CRC in human plasma, and may have the utility to distinguish different disease states.

Flaxseed Supplementation (Not Dietary Fat Restriction) Reduces Prostate Cancer Proliferation Rates in Men Presurgery

Background: Prostate cancer affects one of six men during their lifetime. Dietary factors are postulated to influence the development and progression of prostate cancer. Low-fat diets and flaxseed supplementation may offer potentially protective strategies. Methods: We undertook a multisite, randomized controlled trial to test the effects of low-fat and/or flaxseed-supplemented diets on the biology of the prostate and other biomarkers. Prostate cancer patients (n = 161) scheduled at least 21 days before prostatectomy were randomly assigned to one of the following arms: (a) control (usual diet), (b) flaxseed-supplemented diet (30 g/d), (c) low-fat diet (<20% total energy), or (d) flaxseed-supplemented, low-fat diet. Blood was drawn at baseline and before surgery and analyzed for prostate-specific antigen, sex hormone-binding globulin, testosterone, insulin-like growth factor-I and binding protein-3, C-reactive protein, and total and low-density lipoprotein cholesterol. Tumors were assessed for proliferation (Ki-67, the primary endpoint) and apoptosis. Results: Men were on protocol an average of 30 days. Proliferation rates were significantly lower (P < 0.002) among men assigned to the flaxseed arms. Median Ki-67-positive cells/total nuclei ratios (×100) were 1.66 (flaxseed-supplemented diet) and 1.50 (flaxseed-supplemented, low-fat diet) versus 3.23 (control) and 2.56 (low-fat diet). No differences were observed between arms with regard to side effects, apoptosis, and most serologic endpoints; however, men on low-fat diets experienced significant decreases in serum cholesterol (P = 0.048). Conclusions: Findings suggest that flaxseed is safe and associated with biological alterations that may be protective for prostate cancer. Data also further support low-fat diets to manage serum cholesterol. (Cancer Epidemiol Biomarkers Prev 2008;17(12):3577–87)

Pharmacokinetics of 6-Gingerol, 8-Gingerol, 10-Gingerol, and 6-Shogaol and Conjugate Metabolites in Healthy Human Subjects

Background: Ginger shows promising anticancer properties. No research has examined the pharmacokinetics of the ginger constituents 6-gingerol, 8-gingerol, 10-gingerol, and 6-shogaol in humans. We conducted a clinical trial with 6-gingerol, 8-gingerol, 10-gingerol, and 6-shogaol, examining the pharmacokinetics and tolerability of these analytes and their conjugate metabolites. Methods: Human volunteers were given ginger at doses from 100 mg to 2.0 g (N = 27), and blood samples were obtained at 15 minutes to 72 hours after a single p.o. dose. The participants were allocated in a dose-escalation manner starting with 100 mg. There was a total of three participants at each dose except for 1.0 g (N = 6) and 2.0 g (N = 9). Results: No participant had detectable free 6-gingerol, 8-gingerol, 10-gingerol, or 6-shogaol, but 6-gingerol, 8-gingerol, 10-gingerol, and 6-shogaol glucuronides were detected. The 6-gingerol sulfate conjugate was detected above the 1.0-g dose, but there were no detectable 10-gingerol or 6-shogaol sulfates except for one participant with detectable 8-gingerol sulfate. The Cmax and area under the curve values (mean ± SE) estimated for the 2.0-g dose are 0.85 ± 0.43, 0.23 ± 0.16, 0.53 ± 0.40, and 0.15 ± 0.12 μg/mL; and 65.6.33 ± 44.4, 18.1 ± 20.3, 50.1 ± 49.3, and 10.9 ± 13.0 μg·hr/mL for 6-gingerol, 8-gingerol, 10-gingerol, and 6-shogaol. The corresponding tmax values are 65.6 ± 44.4, 73.1 ± 29.4, 75.0 ± 27.8, and 65.6 ± 22.6 minutes, and the analytes had elimination half-lives <2 hours. The 8-gingerol, 10-gingerol, and 6-shogaol conjugates were present as either glucuronide or sulfate conjugates, not as mixed conjugates, although 6-gingerol and 10-gingerol were an exception. Conclusion: Six-gingerol, 8-gingerol, 10-gingerol, and 6-shogaol are absorbed after p.o. dosing and can be detected as glucuronide and sulfate conjugates. (Cancer Epidemiol Biomarkers Prev 2008;17(8):1930–6)

Predictors of Screening for Breast, Cervical, Colorectal, and Prostatic Cancer Among Community-Based Primary Care Practices

Background: As we enter the year 2000, it is worth looking at whether primary care practices are reaching the goals established in Healthy People 2000 for breast, cervical, colorectal, and prostatic cancer screening. The objectives of this study were (1) to determine the current rates of cancer screening; and (2) to determine which factors predict completion of a single screening test, of all tests for each cancer, and of all procedures for age and sex. Methods: Medical records of 200 eligible patients (100 men and 100 women) from each of 24 community-based primary care practices were abstracted for cancer-screening events. Results: We audited 5125 charts. A Papanicolaou smear was documented for 63.8% of women with an intact cervix within 3 years of the audit .. We found that 46.8% of women had documentation of ever having a discussion of breast self-examination. For breast cancer screening, 41.8% of the women had a clinical breast examination within 1 year, 48.2% aged 40 to 49 years had a mammogram within 2 years, and 38.5% aged 50 years and older had a mammogram within 1 year. Only 29% of women aged 40 to 49 years and 17% of women 50 years and older were current for all breast cancer-screening tests. Among patients 50 years and older, 33% of men and 38% of women had a digital rectal examination within 1 year, 26% of men and 28% of women had a fecal occult blood test within 1 year, and 22% of men and 16.8% of women had a Oexible sigmoidoscopy within 5 years. Of all men 28.7% had a prostate-specific antigen test within 1 year. Completion of all tests relevant for age and sex were documented for 8.6% of women aged 40 to 49 years, 3% of women 50 years and older, and 5% of men 50 years and older. The single most Significant predictor of documented cancer screening was a health maintenance visit. Conclusions: This sample of primary care clinicians has not reached the goals set in Healthy People 2000 for cancer screening. Interventions aimed at increasing the percentage of patients who schedule a health maintenance visit could serve to increase cancer screening and help us reach goals set for the year 2010.

Recruitment of minority and underserved populations in the United States: The centers for population health and health disparities experience

OBJECTIVE The recruitment of minority and underserved individuals to research studies is often problematic. The purpose of this study was to describe the recruitment experiences of projects that actively recruited minority and underserved populations as part of The Centers for Population Health and Health Disparities (CPHHD) initiative. METHODS Principal investigators and research staff from 17 research projects at eight institutions across the United States were surveyed about their recruitment experiences. Investigators reported the study purpose and design, recruitment methods employed, recruitment progress, problems or challenges to recruitment, strategies used to address these problems, and difficulties resulting from Institutional Review Board (IRB) or Health Insurance Portability and Accountability Act of 1996 (HIPAA) requirements. Additionally, information was collected about participant burden and compensation. Burden was classified on a three-level scale. Recruitment results were reported as of March 31, 2007. RESULTS Recruitment attainment ranged from 52% to 184% of the participant recruitment goals. Commonly reported recruitment problems included administrative issues, and difficulties with establishing community partnerships and contacting potential participants. Long study questionnaires, extended follow-up, and narrow eligibility criteria were also problematic. The majority of projects reported difficulties with IRB approvals, though few reported issues related to HIPAA requirements. Attempted solutions to recruitment problems varied across Centers and included using multiple recruitment sites and sources and culturally appropriate invitations to participate. Participant burden and compensation varied widely across the projects, however, accrual appeared to be inversely associated with the amount of participant burden for each project. CONCLUSION Recruitment of minority and underserved populations to clinical trials is necessary to increase study generalizbility and reduce health disparities. Our results demonstrate the importance of flexible study designs which allow adaptation to recruitment challenges. These experiences also highlight the importance of involving community members and reducing participant burden to achieve success in recruiting individuals from minority and underserved populations.