MedicalResearch.com Interview with:
Keiran Smalley, PhD.
Scientific Director, The Comprehensive Melanoma Research Center
Associate Professor The Moffitt Cancer Center & Research Institute, Tampa, FL
Medical Research: What is the background for this study? What are the main findings?
Dr. Smalley: Although many patients with BRAF mutant melanoma respond very well to BRAF inhibitors and the BRAF/MEK inhibitor combination, resistance is commonplace and the majority of those treated ultimately fail therapy. Most studies to date have focused upon the genetic changes that are associated with acquired BRAF and BRAF/MEK inhibitor resistance. We decided to take a different approach and to use proteomics to comprehensively map all of the signaling changes associated with resistance. Our study showed that melanoma cells with resistance to BRAF and BRAF/MEK inhibition were highly invasive and aggressive. This aggressive phenotype was driven through a cell surface receptor called EphA2, and this became upregulated in both melanoma cell cultures and in patient tumors following BRAF inhibitor treatment. As this suggested that the resistant cells would be more metastatic, we then performed animal experiments and analyzed tumors from melanoma patients receiving BRAF inhibitor. These studies showed an increase in EphA2 expression in the metastatic tumors that was lacking in the primary tumors. When we looked at cohorts of melanoma patients who received either a BRAF inhibitor or an older chemotherapy drug, we found that more of the BRAF inhibitor treated patients seemed to develop disease at new sites. Together this suggested that BRAF inhibition may switch the cancer cells to being more metastatic.
MedicalResearch.com Interview with:
Nenad Bursac PhD
Rooney Family Associate Professor of Biomedical Engineering
Associate Professor of Medicine Duke University
Medical Research: What is the background for this study? What are the main findings?
Dr. Bursac: Researchers have tried for a long time to coax human muscle cells (obtained from needle biopsies) into contracting muscle fibers in a dish in order to be able to study human muscle physiology ex vivo. We are the first group that succeeded by carefully optimizing culture conditions including methods to expand and then culture cells in three-dimensional hydrogel matrices under passive tension. By doing so, we made first human muscle model that in response to electrical stimulation generates classical muscle contractile responses (twitch and tetanus). We have also shown that these engineered muscles (that we call "myobundles") contract in response to acetylcholine as it naturally happens when neurons in our body activate muscle. We demonstrated reproducibility and robustness of the approach by generating functional myobundles with similar properties from 10 independent donor muscle samples. We further went to show that myobundles have intact signaling characteristic of native muscle and respond to diverse set of drugs as human muscles do in clinics.
MedicalResearch.com Interview with:
Dr Christos Pliatsikas PhD
Lecturer in Cognitive Psychology School of Psychology
University of Kent Canterbury Kent
Medical Research: What is the background for this study? What are the main findings?
Response: It has been proposed that lifelong bilingualism preserves the white matter structure of older bilinguals because of the increased cognitive demands that come with handling two languages for their entire life. We wanted to extend this by investigating whether active (or "immersive") bilingualism in younger late bilinguals would give similar results.
We showed increased white matter integrity (or myelination) in several white matter tracts that have also been shown to be better preserved in older lifelong bilinguals, compared to monolinguals. Based on our findings, we propose that any benefit of bilingualism to the brain structure is simply an effect of actively handling two languages without presupposing lifelong usage- our participants were only about 30 years old and had been active bilinguals for only about 7-8 years. In other words, immersive bilingualism, even in late bilinguals, leads to structural changes that can bring about benefits in older age, by assisting in the preservation of the white matter structure in the brain.
MedicalResearch.com Interview with:
Professor Marianna Virtanen PhD
Unit of Expertise for Work and Organizations
Finnish Institute of Occupational Health
Helsinki, Finland.
Medical Research: What is the background for this study? What are the main findings?
Professor Virtanen: Risky alcohol use is common among working populations but the contribution of work-related factors such as long working hours has rarely been studied. In the present study we performed the first systematic analysis on published studies regarding long working hours and risky alcohol use and added unpublished individual participant data to the analyses. Altogether 61 studies were included in the cross sectional analysis and 20 studies in the prospective analysis. The pooled cross sectional analysis showed 11% higher alcohol use associated with long working hours. In the prospective analysis we found that working 49-54 hours a week was associated with a 13% increase in the probability of new-onset risky alcohol use and working 55 hours or more with a 12% increased risk.
MedicalResearch.com Interview with:
Javaid Iqbal, MD, MSC (Candidate)
Institute of Medical Sciences, and
Women’s College Research Institute/Women’s College Hospital
University of Toronto, Toronto Canada
What is the background for this study? What are the main findings?
Dr. Iqbal: A woman’s racial/ethnic background predicts her participation in breast cancer control program (i.e., awareness and screening). The ultimate objective of breast cancer control program is to detect cancer at an optimal stage, which is stage I, because women with stage I breast cancer survive longer. Given the racial/ethnic diversity of North America, this poses questions such as “what predicts stage I breast cancer in the multiethnic North American population?”, “what predicts its survival?”, and “does a woman’s ethnic background plays a role in predicting an early stage, and survival?”
We studied 373,563 women diagnosed with invasive breast cancer in the United States between 2004 and 2011. We followed these women for 7 years and recorded whether or not they died of breast cancer, or whether they are still alive. We then divided all women into different ethnic groups, in particular white, black, Chinese, Japanese, and Indian/Pakistani (South Asian). For each racial/ethnic group, we estimated proportions of women who were diagnosed with stage I breast cancer, and risk of death at 7 years. Our aim was to determine if the racial/ethnic differences in early stage breast cancer, and its survival were better explained by intrinsic biological differences in tumor characteristics, or by differences in early-detection of breast cancer.
We found that a woman’s racial/ethnic background predicted the diagnosis of stage I breast cancer, as well as her risk of dying at 7 years after breast cancer. A black woman was less likely than a white woman to be diagnosed with stage I breast cancer. A black woman was also more likely than a white woman to die of stage I breast cancer 7 years after her diagnosis. The Japanese and Chinese women were more likely than white women to be diagnosed with stage I breast cancer. The risk of death at 7 years was lowest for Indian or Pakistani (South Asian) women. Furthermore, even for small sized (2.0) breast cancers the risk of death at 7 years was higher for black women (9%), compared to white women (5%). Compared to white women, small sized breast cancers in black women were more aggressive at diagnosis, and had spread to lymph nodes and other organs.
MedicalResearch.com Interview with:
Terisa P. Gabrielsen, PhD, NCSP
Assistant Professor, School Psychology
Dept. of Counseling Psychology and Special Education
Brigham Young University, Provo, UT 84602
Medical Research: What is the background for this study? What are the main findings?
Dr. Gabrielsen: One of the keys to improving outcomes for individuals with outcomes is to begin intervention as early as possible, which means we need to identify autism symptoms as early as possible, preferably during the early toddler years. The current study grew out of a screening feasibility study to see what would happen if pediatricians followed the AAP guidelines for screening every child for autism at ages 18 and 24 months as part of their regular pediatric care appointments. That study was conducted in a large, independent community pediatrics practice. We found that universal screening of 796 patients helped to identify 10 toddlers with autism who had not previously been referred for evaluations. Physicians had previously identified 3 others with autism in the group, and toddlers with other delays, such as language delays, were also identified through the screening process. We wondered what some possible causes were for the low rate of autism referrals and designed the current study to look for what information was available to a pediatrician during the timespan of a typical pediatric exam. We found that even in toddlers with autism, a brief (10-minute) sample contains an overwhelming ratio of typical behaviors (averaging 89%) compared to infrequent atypical behaviors (11%) that would indicate the presence of autism. We had autism experts identifying the behaviors from videos of the evaluations of children in the previous study, so they had many luxuries that a clinician doesn't have during an exam (i.e., ability to focus on one aspect of development, ability to rewind and re-view behaviors). After watching the 10-minute video observations, we asked our experts, "Would you refer this child for an autism evaluation?" We found that even the experts missed referring a child for an autism evaluation 39% of the time when the only data available were the brief observations.
MedicalResearch.com Interview with:
Gustavo Dayan, MD
Director, Clinical Development
Sanofi Pasteur Discovery Drive
Swiftwater, PA 18370
Medical Research: What is the background for this study? What are the main findings?
Dr. Dayan: This is the first dengue vaccine efficacy trial conducted in Latin America. The trial met its primary objective showing an efficacy of 60.8% against symptomatic VCD (virologically confirmed dengue) after a 3-dose vaccination schedule. Serotype-specific efficacy was also demonstrated against all four serotypes. Furthermore, the dengue vaccine candidate effectively reduced hospitalization due to dengue by 80.3% and severe dengue disease by 95.5% over the 25-month study period.
MedicalResearch.com Interview with:
Teresa Waters PhD
Professor and Chair, Preventive Medicine
University of Tennessee Health Science Center
Memphis TN
Medical Research: What is the background for this study? What are the main findings?
Dr. Waters: On October 1, 2008, Medicare implemented the Hospital-Acquired Conditions (HACs) Initiative, a policy penalizing hospitals for eight complications of hospital care, also known as never events. Under the HACs Initiative, hospitals could no longer justify a higher level Medicare MS-DRG when caring for a patient who developed 1 of the 8 never events. This Initiative was one in a series of CMS payment reforms intended to increase emphasis on value-based purchasing.
We found that Medicare's nonpayment policy was associated with significant improvements in the time trends for central line associated blood stream infections (CLABSIs) and catheter associated urinary tract infections(CAUTIs). For these outcomes, our data from the National Database of Nursing Quality Indicators showed that introduction of the Medicare policy was associated with an 11% reduction in the rate of change in central line associated blood stream infections and a 10% reduction in the rate of change in CAUTIs. We did not find any relationship between introduction of the policy and significant changes in injurious falls or hospital acquired pressure ulcers (two other important never events covered by the policy). We hypothesized that the Hospital-Acquired Conditions Initiative may have a great effect for conditions where there is strong evidence that better hospital processes yield better outcomes or where processes are more conducive to standardization.
MedicalResearch.com Interview with: James Louis Januzzi, Jr, MD, FACC, FESC Director, Cardiac Intensive Care Unit Director, Dennis and Marilyn Barry Fellowship in Cardiology Research Massachusetts General Hospital Boston, MA, 02114. Medical Research: What is the background for this study? What are the main findings? Dr. Januzzi: Evaluation for suspected or proven acute coronary syndrome is...
MedicalResearch.com Interview with:
Oleh Taratula, Ph. D.
Assistant Professor of Pharmaceutics
Department of Pharmaceutical Sciences
College of Pharmacy Oregon State University
Corvallis, OR 97331-3507
Medical Research: What is the background for this study? What are the main findings?
Dr. Taratula: Our research group is focused on the development of novel nanotechnology-based approaches to treat different cancers, including ovarian cancer. For many cancers, surgery is a first choice of treatment. For example, only optimal surgical resection of most abdominal metastases can significantly reduce ovarian cancer recurrence and, therefore, improve patient survival. However, it is challenging to remove most of the cancer tumors and residual cancer cells eventually may lead to cancer relapse. Therefore, our aim is to develop a nanomedicine platform, which could help surgeons achieve maximal tumor resection, using the intraoperative guidance with real-time near infrared (NIR) fluorescence signal. Moreover, we expect that the same nanoplatform could further enhance surgical outcomes by combinatorial phototherapy to be performed intraoperatively after tumor resection to eradicate unresected cancer cells.
Our data published in Nanoscale is the first step towards our main goal. At this point, by utilizing naphthalocyanine, we have developed a single-agent-based nanomedicine platform capable of both NIR fluorescence imaging and combinatorial phototherapy. Naphthalocyanine is a commercially available compound, but its potential clinical application is limited by low water solubility and aggregation. Especially, aggregation diminishes the imaging ability and phototherapeutic efficacy of this compound. To address these shortcomings, we discovered that the loading of naphthalocyanine into the dendrimers significantly enhances water solubility, prevents aggregation and preserves imaging and therapeutic abilities. Our data demonstrated that naphthalocyanine-based nanoplatform can generate a NIR fluorescence signal in the cancer tumors, required for elimination of autofluorescence from healthy tissue and body fluids. Furthermore, our results also indicated that the developed nanoplatform is an efficient therapeutic agent which, upon exposure to NIR light, destroys chemotherapy-resistant ovarian cancer tumors by producing both heat and toxic reactive oxygen species.
Finally, many organic fluorophores, including naphthalocyanine, can undergo photobleaching under exposure to light, which could be misinterpreted as a lack of fluorescence signal during the surgery. We demonstrated that the dendrimer encapsulated naphthalocyanine exhibits extremely high photostability and could overcome the above mentioned issue.
MedicalResearch.com Interview with:
Kasia Joanna Lipska MD, MHS
Assistant Professor of Medicine (Endocrinology)
Yale School of Medicine
New Haven, CT 06520-8020
Medical Research: What is the background for this study? What are the main findings?
Dr. Lipska: Diabetes is common and affects about 1 in 4 older adults (65 years or more). For younger adults with diabetes, most guidelines suggest lowering blood sugar levels to a hemoglobin A1c below 7%. However, in older patients, especially those with complex medical problems, the benefits of this strategy are unclear. What’s more, this strategy can cause harm. Aiming for a hemoglobin A1c below seven increases the risk for hypoglycemia. And older adults are especially susceptible to this risk. As a result, many guidelines suggest that treatment should be more cautious for these vulnerable elders and that aiming for “tight” blood sugar control may not be worth the risk.
Medical Research: What are the main findings?
Dr. Lipska: We looked at diabetes treatment of older adults using nationally representative data from 2001 to 2010. We found that 62% of older adults with diabetes had a hemoglobin A1c below 7%. But what’s really striking is that this proportion was similar for patients who were relatively healthy, for those with intermediate health, and for those with poor health. What’s more, the use of insulin or sulfonylureas (drugs that increase the risk for hypoglycemia) was common and similar across these groups.
MedicalResearch.com Interview with:
Caroline Attardo Genco, PhD
Professor Department of Medicine, Section of Infectious Diseases Department of Microbiology
Boston University School of Medicine
Boston MA
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Genco: Atherosclerosis is a common cardiovascular disease associated with heart attack and stroke. Although it has been shown that a diet high in fat as well as exposure to certain bacteria can cause atherosclerosis (the buildup of fats, cholesterol, and other substances on artery walls which can restrict blood flow), we have for the first time identified distinct gene pathways that are altered by these different stimuli. One of these bacteria, Porphyromonas gingivalis, is found in the mouth of humans with periodontal disease. Another is the bacteria Chlamydia pneumoniae, which causes pneumonia. We found that even though these three different stimuli all cause atherosclerosis, the gene pathways are distinct depending upon stimulus. This is the first study that has performed side-by-side comparison of genome-wide gene expression changes to address this issue.
In this study, we used four experimental groups to compare genome-wide expression changes in vascular tissue. The first group was subjected to Porphyromonas gingivalis, while the second group received Chlamydia pneumoniae. The third group was placed on a high-fat Western style diet, while the fourth group was the control group. In collaboration with the Clinical and Translational Science Institute (CTSI) at Boston University, we performed genome-wide microarray profiling and analysis of vascular tissue from all groups to reveal gene pathways altered in vascular tissue by each treatment group.
These findings may explain how specific infections or high-fat diet may cause atherosclerotic plaques to undergo changes that affect their size and stability and may ultimately lead to a heart attack.
MedicalResearch.com Interview with:
Professor Eleni Petridou
Preventive Medicine & Epidemiology, Department of Hygiene
Epidemiology and Medical Statistics,
Athens University Medical School Athens Greece
Medical Research: What is the background for this study? What are the main findings?
Prof. Petridou: Impressive gains in survival from childhood leukemia have been achieved during the last decades mainly on account of advancements in treatment of the disease. Yet, these big improvements do not seem to be equally shared by all sick children. Disparities in the survival of children suffering leukemia who live in high versus low-income countries, as well as among different racial groups pointed to socio-economic status (SES) of the family as a factor that might adversely affect the outcome. SES, however, is a multifaceted variable comprising economic, social and professional components, which cannot be easily assessed. Therefore, an array of area of residence- and individual family- based proxy indices have been used in order to investigate the association between SES and overall or event-free survival from childhood leukemia. We have intensively searched for published articles around the globe and also analyzed primary data kindly provided by the US National Cancer Institute Surveillance, Epidemiology and End Results Program (SEER) for the period 1973-2010 as well as the Nationwide Registry for Childhood Hematological Malignancies (NARECHEM) in Greece for the period 1996-2011. This study is the first meta-analysis summing up the findings of 29 individual studies and quantifying the adverse effect in the survival due to SES differentials among 60 000 afflicted children. According to the findings, lower socio-economic status children suffering, at least, the more common Acute Lymphoblastic Leukemia (ALL) type have nearly two fold higher death rates compared to those of high socio-economic status. Of note, the SEER data show that the survival gap was wider in the USA with increased risk of death from ALL in the lower SES children (by 20-82%) and widening during the last 40 years time period.
MedicalResearch.com Interview with:
Dr Geeske Peeters
Postdoctoral Research Fellow
School of Public Health
The University of Queensland Australia
Medical Research: What is the background for this study? What are the main findings?
Dr. Peeters:
The hypothesis we set out to investigate was that statin use is associated with reduced joint pain/stiffness and consequently improved physical functioning and quality of life. This hypothesis was based on findings from previous studies suggesting that statin use may prevent the development of radiographic osteoarthritis. However, in contrast with this hypothesis, results from this large study did not demonstrate an association between statin use and reduced onset of joint pain or stiffness. Moreover, statin use did seem to be associated with an increased risk of functional limitations and poorer self-reported health, especially in the middle-aged women.
MedicalResearch.com Interview with:
Hazel B. Nichols, PhD
Assistant Professor, Department of Epidemiology
University of North Carolina
Gillings School of Global Public Health
MedicalResearch:What is the background for this study?
Dr. Nichols: Tamoxifen, a drug that is often used to treat breast cancer, has also been approved to prevent breast cancer in women who may be at high risk for developing the disease. Taking tamoxifen for 5 years can lower breast cancer risk by up to 48%. The United States Federal Drug Administration (FDA) approved tamoxifen for breast cancer prevention more than 15 years ago (in 1998) for women ages 35 and older who are at high risk of breast cancer and who are at low risk for serious side effects.
National estimates show that <1% of women who are eligible to use tamoxifen actually use it for breast cancer prevention. While tamoxifen lowers breast cancer risk it does cause hot flashes and may lead to serious side effects such as cataract, stroke, and uterine cancer. Women who start taking may also stop taking it before the recommended 5-years due to side effects.
We used a tool developed by scientists at the National Cancer Institute (NCI) to calculate whether the benefits of tamoxifen outweighed the risks for women in the Sister Study, a study of more than 50,000 U.S. and Puerto Rican women with a family history of breast cancer. The tool uses information on a woman’s age, race, breast cancer risk, menopausal status, and whether she had a hysterectomy (surgical removal of the uterus) to estimate whether there is no, moderate or strong evidence that the benefits of tamoxifen will outweigh the risks.
MedicalResearch.com Interview with:
John N. Mafi, M.D.
Fellow, Harvard Combined Program in General Medicine
Beth Israel Deaconess Medical Center
Brookline, MA 02446
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Mafi: Headache costs our healthcare system over 30 billion dollars annually. Clinical guidelines recommend conservative treatments for uncomplicated headache, such as counseling on dietary trigger avoidance. The Choosing Wisely Campaign of the American Board of Internal Medicine has in turn identified advanced imaging (e.g. CT or MRI) and opioid or barbiturate medications as low value treatments in the management of headache. In this context we used a nationally representative database to evaluate trends in physician practice patterns on headache management. We found a doubling in use of advanced imaging, referrals to other physicians and no change in opioid/barbiturate medications, although these continued to be used at high rates (18%). We also found a decline in life-style modification counseling, meant to prevent headaches from starting.
MedicalResearch.com Interview with:
Dr. Chao Cheng PhD
Department of Genetics
Geisel School of Medicine at Dartmouth
Hanover 03755, NH
MedicalResearch: What is the background for this study? What are the main findings?
Dr. Chao Cheng: Cancer survival prognosis—“How long do I have, Dr.?” is a topic of great importance to cancer patients and their families. While clinical and pathological variables, such as cancer type, stage, grade, and patient demographics, have long been used to predict survival outcomes, only recently have molecular signatures become incorporated into survival prediction. A molecular approach holds great promise for improving prediction accuracy and additionally elucidating mechanisms of disease, however it is fraught with difficulty due to assay “noise” and “big data” statistical issues, such as the multiple comparisons problem
In this study, we began by analyzing transcription factor binding profiles across available cell lines. By restricting our analysis to transcription factors, DNA expression regulators known to be involved in tumor genesis, we reasoned that we could avoid many of the “big data” issues and achieve results that would make mechanistic and biological sense. We first employed a statistical method we described previously to calculate which genes were the major downstream targets of our transcription factors. With these targets identified, we then analyzed gene expression data using a bioinformatics method to infer the relative activity of each transcription factor based upon the overall expression levels of their gene targets. From here, we incorporated cancer survival data and examined how each transcription factor’s regulatory activity did, or did not, correlate with survival.
The most prognostic transcription factor was E2F4, a member of the E2F family and a known regulator of the cell cycle. We therefore restricted our analysis to E2F4 and examined how its activity level impacted survival in breast cancer patients.
We found that tumors with high E2F4 regulatory activity as compared to low E2F4 regulatory activity had much worse survival outcomes. These results were stable even after controlling for tumor stage, grade, patient age, and treatment, and were based on data from over 1900 patients across eight independent datasets. These results demonstrate that E2F4 is an independent and enhancing predictor of survival above the currently examined variables.
MedicalResearch.com Interview with:
Dr. Robert S. DiPaola
Director, Rutgers Cancer Institute of New Jersey
New Brunswick, NJ 08901
Medical Research: What is the background for this study? What are the main findings?
Dr. DiPaola: Despite significant recent improvements in the treatment of advanced castration-resistant prostate cancer, there remains a need for a standard therapy for those patients who have an early relapse with PSA progression after local therapy. Immune therapy with poxvirus vaccines are optimal, because they can induce potent immune responses by mimicking natural infection, have great flexibility regarding antigen composition and are easily administered.
ECOG-ACRIN Cancer Research Group investigators conducted a Phase II clinical trial examining adult patients from member institutions with advanced prostate cancer (as evidenced by two rising prostate-specific antigen or PSA values and no visible metastasis) who had prior surgery or radiation. We explored two different experimental treatment options.
In step one, patients were treated with PROSTVAC-V/TRICOM and PROSTVAC-F/TRICOM. PROSTVAC-V is derived from a vaccinia virus that was used for many years to vaccinate against smallpox. This virus is modified to produce a PSA protein that helps focus the body’s immune response to the PSA in the prostate tumor. In addition, it is modified to produce three other proteins that help increase an immune cell’s ability to destroy its target (TRICOM). PROSTVAC-F is made from the fowlpox virus, which is found in birds and not known to cause any human disease. It contains the same genetic material as PROSTAC-V, but is given multiple times to further boost the body’s immune system.
Patients in the study were given one cycle of PROSTVAC-V/TRICOM followed by PROSTVAC-F/TRICOM for subsequent cycles in combination with a drug known as GM-CSF. GM-CSF is a protein normally made by the body to increase the amount of certain white blood cells and make them more active. When in drug form, it is used to boost the body’s immune system to fight off disease. After six months from first treatment, 25 of 40 eligible patients (63 percent) were found to have no disease progression and experienced minimal toxicity. The rate of rise of PSA also decreased. The second part of the study included the addition of hormone therapy (androgen ablation) to the PROSTVAC-VF/TRICOM combination. In the 27 patients eligible for this step, 20 patients (74 percent) experienced a significant response at seven months.