Newswise — In a sample study, researchers at Johns Hopkins say they have found an association between the makeup of an individual’s microbiome and head and neck cancer, a finding that potentially advances the quest for faster and more accurate cancer diagnosis and therapy.
In a report on the research published on May 30 in Oncotarget, the scientists say that populations of the human microbiome—the collection of normal bacteria inhabiting peoples’ bodies — can help discriminate between patients with head and neck cancer and healthy individuals.
“One of the goals of our research is to better understand how the microbiome may influence the immune response to cancer and how the immune response affects the microbiome in turn,” says Rafael Guerrero-Preston, Dr PH, MPH, assistant professor of otolaryngology–head and neck surgery at the Johns Hopkins University School of Medicine and a member of its Kimmel Cancer Center. “Our findings suggest that we may one day use the composition of the microbiome to test for disease.”
Trillions of microbes colonize the adult body. Changes in this community have already been tied to the risk and presence of arthritis, multiple sclerosis, irritable bowel syndrome and cancer. With more information on how these microbes are connected with cancer and cancer risk factors, such as genetic predispositions, smoking and other environmental factors, researchers hope to create individualized screening and treatment plans for cancer patients and for those at an increased cancer risk.
For this study, Guerrero-Preston and his colleagues extracted bacterial DNA from the saliva of 42 patients. Seventeen samples were drawn from people with head and neck squamous cell carcinoma, seven of which were positive for HPV and 10 of which were HPV-negative. Twenty-five noncancerous samples were used as a control.
The bacterial DNA found in the saliva was sequenced and sorted into groups of highly related populations. Through further DNA analysis, researchers were then able to determine the category, or genus, of bacteria to which each group belonged.
The researchers found differences in the bacterial populations present in cancerous versus noncancerous samples. Samples from patients with tumors, for example, showed increased populations of Streptococcus, Dialister and Veillonella genera, as well as decreased populations of Neisseria, Aggregatibacter, Haemophilus and Leptotrichia genera with respect to controls. Tumor samples also showed an increased prevalence of the Lactobacillus genus, which was present in 9.1% of tumor samples and in only 0.1% of the healthy controls. In addition, the researchers found correlations between the types of bacteria present and the patients’ HPV statuses. HPV-positive samples had increased abundances of Gemellaceae, Leuconostoc and Veillonella genera when compared to HPV-negative samples. Veillonella, for example, was present in 15% of HPV-positive tumor samples but was only present in 9.4% of HPV-negative tumor samples.
“We see some specific bacterial populations that are increased or lost in the presence of cancer when compared to healthy controls,” says Guerrero-Preston. This may mean that either the tumor is affecting the environment in the mouth by killing bacteria that would fight cancer or that the patients may be predisposed to cancer because they originally lacked bacteria that prevent tumor development.
Guerrero-Preston cautions that these findings do not establish a direct cause-and-effect link between any of the bacteria and head and neck cancer, stressing the preliminary nature of these assays. In particular, he says that future research needs to distinguish between the detection of bacterial DNA and the effects of the bacteria themselves. In order to determine how bacteria affect the oral environment, Guerrero-Preston’s team intends to look at which genes bacteria have turned on in saliva samples.
If the differences in the microbiome between cancerous and noncancerous/HPV-positive and HPV-negative tumors are confirmed in further studies with more patients, doctors may be able to use the same sequencing tools as Guerrero-Preston to quickly and accurately screen and diagnose patients based on the bacteria present in their mouths.
Guerrero-Preston says other research on the human microbiome has found that bacteria only present in the gut influence immunotherapies that utilize the body’s immune system to combat cancer in other tissues. With a greater understanding of how bacteria interact with a patient’s immune system, doctors may be better able to determine if immunotherapy will be effective and what side effects the patient may experience as a result of the treatment.
Other scientists who contributed to the study include Jessica Bondy, Fahcina Lawson, Oluwasina Folawiyo, Christina Michailidi, Tal Hadar, Maartje G. Noordhuis, Wayne Koch and David Sidransky of the Johns Hopkins University School of Medicine; Filipa Godoy-Vitorino, Arnold Rodriguez and Herminio Gonzalez of the Inter American University of Puerto Rico; Anne Jedlicka and Amanda Dziedzic of the Johns Hopkins Bloomberg School of Public Health; and Rajagowthamee Thangavel of the Icahn School of Medicine at Mount Sinai.
Funding for the study was provided by National Cancer Institute grants (U01CA84986, K01CA164092, CA121113), National Institute of Dental and Craniofacial Research grants (P50DE019032, RC2DE20957).
Saeshin Precision Company of Korea, one of the leading manufacturers of Implant, Endo and lab motors is opening an office in Irvine, CA as of July 5, 2016. This office will serve as the North American headquarters and will provide support to the dealer network, dentists and laboratories. Saeshin’s Surgical/Piezo Implant motor is one of only a few combination units on the market. Over the past ten years, Saeshin has been supplying products through the dealer network to the USA by shipping from Korea. Now, with the new location, the company expects to supply product more quickly and service customers in a more efficient manner.
For more information about Saeshin Precision products log on to: Saeshin.com or call (949) 825-6925
Source: Saeshin Precision
Highlights from all four days of the 2016 Nobel Biocare Global Symposium in New York City.
Jensen Dental and Peter Pizzi, CDT, MDT have teamed up to offer several hands on courses and Virtual Study Clubs in Q3 and Q4 2016. “The hands-on courses and virtual study clubs being offered provide a unique opportunity for dental technicians to expand their knowledge, sharpen their skills, and get some great tips and tricks that will help them grow their business from one of the best dental technicians in the country”, said Kevin Mahan, VP Sales and Marketing at Jensen Dental.
Attendees of the hands on courses (TX, MN, NY) and virtual study clubs (online) will learn how incorporating communication, material options and selection, photography as an aid in ceramic builds, and color communication into their daily regiment will enable them (and their dentists) to achieve the highest level of predictability and satisfaction.
“Digital and material advancements continue to change the artistic process, and our world of work is changing! Creativity. Productivity. Technology -- these are the building blocks of every successful dental laboratory. During my courses and online clubs, using Jensen’s InSync Ceramic as my canvas, I will show attendees how easily all can be incorporated into their business so they can stay current, relevant and profitable for years to come”, said Peter Pizzi, CDT, MDT.
Visit Jensen Dental online at jensendental.com for detailed hands-on course and virtual study club information.
New guidance on pediatric sedation recommends more advanced skills on the part of practitioners, unifies guidelines for medicine and dentistry, and offers clarifications on monitoring modalities and other methods to improve safety and outcomes.
Knight Dental Group, Inc. announced the completion of a 100 percent equity investment in Thompson Suburban Dental Laboratories, Inc. This transaction was completed on June 1, 2016.
The recent acquisition will strengthen Knight’s presence in the North Eastern US which began with the acquisitions of Astor Dental Studio, Lema Dental Laboratory and Regal Technologies in the New York area.
“With the completion of the Thompson Suburban acquisition, we have established a stronger presence in a major dental market in the US eastern corridor. We are pleased to welcome our new Thompson Suburban team and grateful to have the leadership of William (Bill) Grill, CDT in our Senior Management Team” said Warren Rogers, CEO of Knight Dental Group.
“We are excited about our future with the Knight Dental Group and look forward to our partnership and moving forward. We share a common goal of delivering high quality dental device solutions and services to the dental community in North America. The partnership will give Thompson Suburban an opportunity to grow our brand in all regions of the country” said William (Bill) Grill, President of Thompson Suburban.
“This strategic investment of Thompson Suburban in a key region of the United States and Knight’s recent acquisitions of Barron’s and Bavo Dental Laboratories will position us as a leading and growing Dental Laboratory group. We will continue our plans to be a market leader in the North American sector and investing in strategically placed high quality dental laboratories” said Harmeet Bindra, Leixir Private Holdings CEO.
Thompson Suburban will serve as the Implant Center of Excellence as well as a Mid-Atlantic Regional Hub for the Group.
The National Institute of Dental and Craniofacial Research (NIDCR), part of the National Institutes of Health (NIH), has awarded Drs. Brian Schmidt and Seiichi Yamano a $1.2 M (3-year) grant to test whether their nonviral gene delivery method can effectively and safely treat oral cancer pain.
Quality of life for oral cancer patients can be dismal.
“Most of my oral cancer patients have severe pain,” says Brian L. Schmidt, DDS, MD, PhD, professor in the Department of Oral and Maxillofacial Surgery at New York University College of Dentistry (NYU Dentistry) and director of NYU’s Bluestone Center for Clinical Research and of the NYU Oral Cancer Center. “A recent study revealed that oral cancer pain is often more severe than pain from any other type of cancer.”
Due to their severe pain, oral cancer patients have difficulty eating, drinking, or talking, leaving doctors with little or no choice other than to prescribe high doses of opioid medications.
“The clinical challenge of treating oral cancer pain is then compounded by the off-target effects produced by pharmacological agents which lack anatomical specificity,” notes Schmidt, “since high opioid doses generate unwanted side effects that create additional unintended suffering for the patient.”
“Gene therapy is emerging as an exciting alternative to opioids for the treatment of cancer pain,” says Seiichi Yamano, DDS, PhD, DMD, MMSc, associate professor in the Department of Prosthodontics at NYU Dentistry. “We seek to alleviate oral cancer pain by reversing epigenetic changes. Our gene therapy method will set the stage for a new class of medicines that selectively disrupt nociceptive signaling with fewer off-target effects. Our long-term goal is to develop an effective and safe treatment for oral cancer pain.”
Schmidt’s research team demonstrated that OPRM1 (the gene for the µ-opioid receptor) is methylated and down regulated in oral cancer tumors. They also demonstrated that OPRM1 re-expression following viral gene transduction significantly reduced cancer pain in a preclinical model. Expression of the µ-opioid receptor on the cancer led to the secretion of opioids into the cancer microenvironment.
Because of safety concerns and viral transduction inefficiency, Yamano created two novel nonviral hybrid vectors: a cell-permeable peptide (CPP) combined with either a cationic lipid (CPP/lipid) or a cationic polymer (CPP/polymer). These nonviral vectors have excellent transfection efficiency with little cytotoxicity across a range of cell lines including different types of cancer cells.
“In addition to their transfection efficiency, my non-viral vectors preferentially transfect oral cancer cells compared to normal cells,” says Yamano. “Transfection efficiency using the nonviral vector in oral cancer cells showed eight-fold more gene transfer than normal cells and higher expression than that for an adenoviral vector.
In preliminary work funded by a High Priority, Short-Term Project Award (R56DE025393) from the NIDCR, Schmidt and Yamano demonstrated that the nonviral vectors could be used to deliver OPRM1 to oral cancers and reverse cancer pain in the preclinical model.
“Dr. Yamano and I collaborated over the last five years in preparation for the work described in this current grant,” notes Schmidt. “I found that delivery of the OPRM1 gene into the cancer reversed cancer pain. I just needed a safe method to deliver the gene. Yamano’s nonviral method is ideal. Our previously awarded bridge funding allowed us to develop preliminary data for the application. Our long-term goal is to develop an effective and safe treatment for oral cancer pain. These studies are a significant step toward that goal. We foresee clinicians directly inoculating our nonviral vector into oral cancers.”
A high proportion of 12 to 14 year olds are regularly consuming sports drinks socially, increasing their risk of obesity and tooth erosion, concludes a Cardiff University School of Dentistry survey.
Published today in the British Dental Journal, the survey looked at 160 children in four schools across South Wales and concluded that children are attracted to sports drinks because of their sweet taste, low price, and availability, with most parents and children not aware that sports drinks are not intended for consumption by children.
Half of the children surveyed claimed to drink sports drinks socially and most (80%) purchased them in local shops. The majority (90%) also claimed that taste was a factor and only 18% claimed to drink them because of the perceived performance enhancing effect. Price was one of the top three recorded reasons for purchase and, of particular concern, 26% of children also cited leisure centres as purchase sources.
Maria Morgan, senior lecturer in dental public health at Cardiff University, said: "The purpose of sports drinks are being misunderstood and this study clearly shows evidence of high school age children being attracted to these high sugar and low pH level drinks, leading to an increased risk of dental cavities, enamel erosion and obesity.
"Dental health professionals should be aware of the popularity of sports drinks with children when giving health education or advice or designing health promotion initiatives."
The Faculty of Sport and Exercise Medicine (FSEM) is calling for tighter regulation around the price, availability and marketing of sports drinks to children, especially surrounding the school area, to safeguard general and dental health.
Dr Paul D Jackson, President of the FSEM UK, said: "The proportion of children in this study who consume high carbohydrate drinks, which are designed for sport, in a recreational non-sporting context is of concern.
"Sports drinks are intended for athletes taking part in endurance and intense sporting events, they are also connected with tooth decay in athletesi and should be used following the advice of dental and healthcare teams dedicated to looking after athletes. Water or milk is sufficient enough to hydrate active children, high sugar sports drinks are unnecessary for children and most adults."
Russ Ladwa, chair of the British Dental Association's Health and Science Committee, added: "The rise of sports drinks as just another soft drink option among children is a real cause for concern, and both parents and government must take note. They are laden with acids and sugars, and could be behind the decay problems we're now seeing among top footballersii.
"Sports drinks are rarely a healthy choice, and marketing them to the general population, and young people in particular, is grossly irresponsible. Elite athletes might have reason to use them, but for almost everyone else they represent a real risk to both their oral and their general health."
The survey also concluded that there is particular confusion over the definition of a sports versus an energy drink. However, from a dental and wider health perspective, these two drinks have similar detrimental effects due to their high sugar content and low pH.
In supermarkets and shops, sports drinks are often sold alongside other sugar sweetened beverages. This is misleading children and parents by indicating that they are meant for use by everyone.
The study - A survey of sports drinks consumption amongst adolescents - is published in the British Dental Journal.
i Faculty of Sport and Exercise Medicine UK, Position Statement, Oral Health in Sport, October 2014, Professor Ian Needleman
ii UCL Eastman Centre for Oral Health and Performance Better Oral Health for Footballers Needed, statement published 3 November 2015. Poor oral health including active caries in 187 UK professional male football players: clinical dental examination performed by dentists, Br J Sports Med 2016;50:41-44 doi:10.1136/bjsports-2015-094953, Professor Ian Needleman et al.
Seoul, Republic of Korea – At the 94th General Session & Exhibition of the International Association for Dental Research, researcher W. Peter Holbrook, University of Iceland, presented a study titled “Development of Drugs for Local Treatment of Oral Conditions.” The IADR General Session was held in conjunction with the 3rd Meeting of the IADR Asia Pacific Region and the 35th Annual Meeting of the IADR Korean Division.
Several medications commonly prescribed for oral mucosal administration are actually intended for transdermal application. Many conditions affecting the oral mucosa require frequent or long-term treatments and some treatments are systemically applied. Clinical resistance and patient intolerance of such treatments may develop. There is thus a constant need to address these problems through the development of less side-effect prone drugs.
Researchers at the University of Iceland have developed several new formulations for topical treatments of oral mucosal conditions and carried out appropriate clinical trials. The main area of this research has been the inhibition of matrix metallo-proteinase activity using topical doxycycline, initially in order to treat aphthous ulceration. The antimicrobial compound monocaprin was also tested for activity against herpes virus and, in combination with doxycycline, was developed in an active formulation for treating cold sores (canker sores). Monocaprin also has anticandidal activity that has been evaluated among geriatric patients with denture stomatitis.
Topical application of doxycycline was very effective in promoting healing of mucosal lesions. Monocaprin reduced counts of Candida rapidly and significantly. The results of these clinical studies have been very promising when compared to the conventional treatments available in Iceland and abroad. Stability of the active components has recently been effectively addressed and current research is aimed at different types of drug delivery systems in order to optimize drug delivery to the local mucosal site. This includes drug release time and mucoadhesive capacity of the formulation, thereby attempting to develop more disease-specific drug delivery systems.
This research was funded by grants from the Icelandic Research Council (Rannis) and the University of Iceland.
Seoul, Republic of Korea – At the 94th General Session & Exhibition of the International Association for Dental Research, researcher Jonas Sundberg, University of Gothenburg, Sweden, presented a study titled “Increased Expression of p16 in Oral Leukoplakia the Last Decade.”
During the last two decades an increase in incidence of oropharyngeal carcinomas related to human papilloma virus (HPV) infection has been reported. Although a casual association between lekoplakia, oral cancer, and HPV has been suggested in several reports, no conclusive evidence has been presented. To assess the presence of HPV, the tumor suppressing protein p16 is commonly used as a surrogate marker for HPV infection. The aim of the present study is to investigate whether p16 expression in tissue specimens from lekoplakia has increased during the last decade, which may indicate an increase in incidence of oral HPV infection.
A patient cohort with tissue specimens obtained between 1992 and 2001 and a cohort where specimens were obtained between 2011 and 2015 and with histopathological diagnoses of benign hyperkeratosis or hyperkeratosis with dysplasia were examined. Immunohistochemistry was performed using a monoclonal antibody (clone E6H4; Roche Ltd) visualizing p16. Digitalized images of sections were obtained and a semiquantitative scale (0-5) was used to enumarate p16 expression in oral epithelium.
In the 2011-2015 cohort lekoplakia epithelium showed a significant increase (P = .02) in grade 4 and 5 p16 expression in comparison with lekoplakia epithelium in the 1992-2001 cohort. In lekoplakia presenting with dysplasia, grade 4 and 5 p16 expression also increased significantly (P = .0001) over time when comparing the cohorts. The results indicate an increase in HPV infection in lekoplakia during the last decade. Researchers are further investigating the presence of HPV DNA utilizing polymerase chain reaction is presently undertaken.
This research was funded by the Regional Research Council, Region Västra Götaland, Assar Gabrielsson Foundation and the Swedish Dental Society.