Folate intake and the risk of oral cavity and pharyngeal cancer: a pooled analysis within the International Head and Neck Cancer Epidemiology Consortium

Urine and serum metabolomic analysis of endometrial cancer diagnosis and classification based on ultra-performance liquid chromatography mass spectrometry

OBJECTIVE

This study aimed to reveal the urinary and serum metabolic pattern of endometrial cancer (EC) and establish diagnostic models to identify EC from controls, high-risk from low-risk EC, and type II from type I EC.

METHOD

This study included 146 EC patients (comprising 79 low-risk and 67 high-risk patients, including 124 type I and 22 type II) and 59 controls. The serum and urine samples were analyzed using ultraperformance liquid chromatography mass spectrometry. Analysis was used to elucidate the distinct metabolites and altered metabolic pathways. Receiver operating characteristic (ROC) analyses were employed to discover and validate the potential biomarker models.

RESULTS

Serum and urine metabolomes displayed significant differences between EC and controls, with metabolites related to amino acid and nicotinamide metabolisms. The serum and urine panels distinguished these two groups with Area Under the Curve (AUC) of 0.821 and 0.902, respectively. The panel consisting of serum and urine metabolites demonstrated the best predictive ability (AUC = 0.953 and 0.976 in discovering and validation group). In comparing high-risk and low risk EC, differential metabolites were enriched in purine and glutamine metabolism. The AUC values for serum and urine panels were 0.818, and 0.843, respectively. The combined panel exhibited better predictive accuracy (0.881 in discovering group and 0.936 in external validation). In the comparison between type I and type II group, altered folic acid metabolism was identified. The serum, urine and combined panels discriminated these two groups with the AUC of 0.829, 0.913 and 0.922, respectively.

CONCLUSION

The combined urine and serum metabolome effectively revealed the metabolic patterns in EC patients, offering valuable diagnostic models for EC diagnosis and classification.

Folic acid: friend or foe in cancer therapy

Folic acid plays a crucial role in diverse biological processes, notably cell maturation and proliferation. Here, we performed a literature review using articles listed in electronic databases, such as PubMed, Scopus, MEDLINE, and Google Scholar. In this review article, we describe contradictory data regarding the role of folic acid in cancer development and progression. While some studies have confirmed its beneficial effects in diminishing the risk of various cancers, others have reported a potential carcinogenic effect. The current narrative review elucidates these conflicting data by highlighting the possible molecular mechanisms explaining each point of view. Further multicenter molecular and genetic studies, in addition to human randomized clinical trials, are necessary to provide a more comprehensive understanding of the relationship between folic acid and cancer.

Urine metabolomics for assessing fertility-sparing treatment efficacy in endometrial cancer: a non-invasive approach using ultra-performance liquid chromatography mass spectrometry

OBJECTIVE

This study aimed to reveal the urine metabolic change of endometrial cancer (EC) patients during fertility-sparing treatment and establish non-invasive predictive models to identify patients with complete remission (CR).

METHOD

This study enrolled 20 EC patients prior to treatment (PT) and 22 patients with CR, aged 25-40 years. Eligibility criteria consisted of stage IA high-grade EC, lesions confined to endometrium, normal hepatic and renal function, normal urine test, no contraindication for fertility-sparing treatment and no prior therapy. Urine samples were analyzed using ultraperformance liquid chromatography mass spectrometry (UPLC-MS), a technique chosen for its high sensitivity and resolution, allows for rapid, accurate identification and quantification of metabolites, providing a comprehensive metabolic profile and facilitating the discovery of potential biomarkers. Analytical techniques were employed to determine distinct metabolites and altered metabolic pathways. The statistical analyses were performed using univariate and multivariate analyses, logistic regression and receiver operating characteristic (ROC) curves to discover and validate the potential biomarker models.

RESULTS

A total of 108 different urine metabolomes were identified between CR and PT groups. These metabolites were enriched in ascorbate and aldarate metabolism, one carbon pool by folate, and some amino acid metabolisms pathways. A panel consisting of Baicalin, 5beta-1,3,7 (11)-Eudesmatrien-8-one, Indolylacryloylglycine, Edulitine, and Physapubenolide were selected as biomarkers, which demonstrated the best predictive ability with the AUC values of 0.982/0.851 in training/10-fold-cross-validation group, achieving a sensitivity of 0.975 and specificity of 0.967, respectively.

CONCLUSION

The urine metabolic analysis revealed the metabolic changes in EC patients during the fertility-sparing treatment. The predictive biomarkers present great potential diagnostic value in fertility-sparing treatments for EC patients, offering a less invasive means of monitoring treatment efficacy. Further research should explore the mechanistic underpinnings of these metabolic changes and validate the biomarker panel in larger, diverse populations due to the small sample size and single-institution nature of our study.

Uncovering the Hidden Dangers and Molecular Mechanisms of Excess Folate: A Narrative Review

This review delves into the intricate relationship between excess folate (vitamin B9) intake, especially its synthetic form, namely, folic acid, and its implications on health and disease. While folate plays a pivotal role in the one-carbon cycle, which is essential for DNA synthesis, repair, and methylation, concerns arise about its excessive intake. The literature underscores potential deleterious effects, such as an increased risk of carcinogenesis; disruption in DNA methylation; and impacts on embryogenesis, pregnancy outcomes, neurodevelopment, and disease risk. Notably, these consequences stretch beyond the immediate effects, potentially influencing future generations through epigenetic reprogramming. The molecular mechanisms underlying these effects were examined, including altered one-carbon metabolism, the accumulation of unmetabolized folic acid, vitamin-B12-dependent mechanisms, altered methylation patterns, and interactions with critical receptors and signaling pathways. Furthermore, differences in the effects and mechanisms mediated by folic acid compared with natural folate are highlighted. Given the widespread folic acid supplementation, it is imperative to further research its optimal intake levels and the molecular pathways impacted by its excessive intake, ensuring the health and well-being of the global population.

Decreased expression of hsa_circ_0112879 in oral squamous cell carcinoma and its clinicopathological implications

Background

To identify differently expressed circular RNA (circRNA) in oral squamous cell carcinoma (OSCC) and adjacent normal tissue, construct a hsa_circ_0112879-related microRNAs (miRNAs) prognostic model, and discuss the circRNA as a biomarker for early diagnosis of OSCC.

Methods

The expression of hsa_circ_0112879 in OSCC cell lines and tissues was detected by quantitative real-time polymerase chain reaction (qRT-PCR). A receiver operating characteristic (ROC) curve was plotted to estimate its clinical significance. The potential miRNA and messenger RNA (mRNA) binding to hsa_circ_009755 were predicted by R software edgeR package. Based on the median value of the risk score in the all-sample cohort, all the included patients with OSCC were divided into either high- or low-risk groups, and Kaplan-Meier analysis was performed. The ROC curve was used to verify the accuracy of the risk signature in predicting the prognosis of OSCC. By univariable Cox, least absolute shrinkage and selection operator (LASSO), and multivariable Cox analyses, we constructed a hsa_circ_0112879-related miRNAs risk model to forecast the prognosis of OSCC.

Results

The expression of hsa_circ_0112879 was significantly downregulated in the OSCC tissues and cell lines. The expression level was statistically correlated with the pathological differentiation of OSCC tumors (P=0.0285). Furthermore, 141 differentially expressed hsa_circ_0112879-related miRNAs were obtained [|log2FC| >1, false discovery rate (FDR) <0.05], of which 70 miRNAs were up-regulated in OSCC tissues, whereas 71 miRNAs were down-regulated in OSCC tissues. The area under the ROC curve (AUC) at 1-, 3-, and 5-year in the all-sample cohort was 0.591, 0.689, and 0.618, respectively. The toll-like receptor signaling pathway, Janus tyrosine kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway, nucleotide-binding and oligomerization domain (NOD)-like receptor signaling pathway, and T-cell receptor (TCR) signaling pathway were mainly enriched in the high-risk group.

Conclusions

The model and nomogram constructed herein has the ability to discriminate the prognosis of OSCC patients. Hsa_circ_0112879 may serve as a novel biomarker in the diagnosis and prognosis of OSCC.

The Way to Malignant Transformation: Can Epigenetic Alterations Be Used to Diagnose Early-Stage Head and Neck Cancer?

Identifying and treating tumors early is the key to secondary prevention in cancer control. At present, prevention of oral cancer is still challenging because the molecular drivers responsible for malignant transformation of the 11 clinically defined oral potentially malignant disorders are still unknown. In this review, we focused on studies that elucidate the epigenetic alterations demarcating malignant and nonmalignant epigenomes and prioritized findings from clinical samples. Head and neck included, the genomes of many cancer types are largely hypomethylated and accompanied by focal hypermethylation on certain specific regions. We revisited prior studies that demonstrated that sufficient uptake of folate, the primary dietary methyl donor, is associated with oral cancer reduction. As epigenetically driven phenotypic plasticity, a newly recognized hallmark of cancer, has been linked to tumor initiation, cell fate determination, and drug resistance, we discussed prior findings that might be associated with this hallmark, including gene clusters (11q13.3, 19q13.43, 20q11.2, 22q11-13) with great potential for oral cancer biomarkers, and successful examples in screening early-stage nasopharyngeal carcinoma. Although one-size-fits-all approaches have been shown to be ineffective in most cancer therapies, the rapid development of epigenome sequencing methods raises the possibility that this nonmutagenic approach may be an exception. Only time will tell.

Oral Cavity Squamous Cell Carcinoma Risk Factors: State of the Art

Head and neck (HN) squamous cell carcinomas (SCCs) originate from the epithelial cells of the mucosal linings of the upper aerodigestive tract, which includes the oral cavity, the pharynx, the larynx, and the sinonasal cavities. There are many associated risk factors, including alcohol drinking coupled with tobacco use, which accounts for 70% to 80% of HNSCCs. Human papilloma virus (HPV) is another independent risk factor for oropharyngeal SCC, but it is only a minor contributor to oral cavity SCC (OSCC). Betel quid chewing is also an established risk factor in southeast Asian countries. However, OSCC, and especially oral tongue cancer, incidence has been reported to be increasing in several countries, suggesting risk factors that have not been identified yet. This review summarizes the established risk factors for oral cavity squamous cell carcinomas and examines other undemonstrated risk factors for HNSCC.

Evolution of the Incidence of Oral Cavity Cancers in the Elderly from 1990 to 2018

OBJECTIVES

To describe the evolution of the incidence of oral cavity cancers (OCC) among elderly patients in France between 1990 and 2018 and to compare it to the incidence of other cancers sharing the same main risk factors.

MATERIAL AND METHODS

The incidence of cancers in mainland France from 1990 to 2018 was estimated from incidence data observed in every cancer registry of the Francim network. Incidence was modeled by a 2-dimensional penalized spline of age and year of diagnosis, associated with a random effect corresponding to the registry. The elderly population was divided into two groups: 70-79 years old and ≥80 years old.

RESULTS

There was a 72% increase in the number of OCC cases in women over 70 years of age between the periods 1990-1999 and 2010-2018. As for men, there was a stabilization in the number of cases (+2%). Over the same period, for laryngeal and hypopharyngeal cancers, there was a decrease in incidence in elderly men and an increase in elderly women, although less marked than for OCC.

CONCLUSIONS

Since the 1990s, the incidence of OCC has been increasing in elderly subjects in France, particularly in women. Population aging and growth or alcohol and tobacco consumption alone do not seem to explain this increase, which is not observed in the same proportions for other upper aerodigestive tract cancer subsites sharing the same main risk factors.

Associations of Body Mass Index and Waist Circumference with the Risk of Head and Neck Cancer: A National Population-Based Study

Background: We investigated the association between BMI and HNC subtype incidence in a cohort study of ten million people, adjusting for the effect of smoking and drinking. We also investigated the relationship between waist circumference (WC) and HNC subtype. Methods: All data used in this study originated from the Korean National Health Insurance Service database. We analysed subjects who had undergone health check-ups in 2009 and monitored subjects until 2018 (n = 10,585,852). Finally, 9,598,085 subjects were included after exclusions. We collected variables that could affect the risk of HNC. Cox proportional hazards regression analysis was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results: The overall incidence of HNC was higher in the low BMI category (BMI < 18.5 according to WHO recommendations for Asian people) (HR: 1.322; 95% CI: 1.195−1.464) compared with the normal BMI category. Among the HNC cases, the incidence rates of laryngeal (HR: 1.3; 95% CI: 1.085−1.558), oral cavity (HR: 1.277; 95% CI: 1.011−1.611), and oropharyngeal (HR: 1.584; 95% CI: 1.25−2.008) cancers were higher in the low BMI category compared with the normal BMI category. No significant association was detected between low BMI and sinus cancer, salivary gland cancer, or nasopharyngeal cancer. The low WC category (<80 cm in men and <75 cm in women) was related to a risk of hypopharyngeal (HR: 1.268; 95% CI: 1.061−1.514) and laryngeal (HR: 1.118; 95% CI: 1.007−1.241) cancers. The HR for occurrence of HNC was high in underweight participants according to smoking status (1.219 for never smoker vs. 1.448 for ever smoker, p for interaction = 0.0015) and drinking status (1.193 for never drinker vs. 1.448 for ever drinker, p for interaction = 0.0044). Conclusions: Low BMI was associated with the risk of some types of HNC. The results of this study could assist etiological investigations and prevention strategies.

Developing a Stacked Ensemble-Based Classification Scheme to Predict Second Primary Cancers in Head and Neck Cancer Survivors

Despite a considerable expansion in the present therapeutic repertoire for other malignancy managements, mortality from head and neck cancer (HNC) has not significantly improved in recent decades. Moreover, the second primary cancer (SPC) diagnoses increased in patients with HNC, but studies providing evidence to support SPCs prediction in HNC are lacking. Several base classifiers are integrated forming an ensemble meta-classifier using a stacked ensemble method to predict SPCs and find out relevant risk features in patients with HNC. The balanced accuracy and area under the curve (AUC) are over 0.761 and 0.847, with an approximately 2% and 3% increase, respectively, compared to the best individual base classifier. Our study found the top six ensemble risk features, such as body mass index, primary site of HNC, clinical nodal (N) status, primary site surgical margins, sex, and pathologic nodal (N) status. This will help clinicians screen HNC survivors before SPCs occur.

Association between Oral Cancer and Diet: An Update

Oral cancer, included within head and neck cancer, is the sixth most common malignant neoplasm in the world. The main etiological factors are tobacco and alcohol, although currently, diet is considered an important determinant for its development. Several dietary nutrients have specific mechanisms of action, contributing to both protection against cancer and increasing the risk for development, growth, and spread. Foods such as fruits, vegetables, curcumin, and green tea can reduce the risk of oral cancer, while the so-called pro-inflammatory diet, rich in red meat and fried foods, can enhance the risk of occurrence. Dietary factors with a protective effect show different mechanisms that complement and overlap with antioxidant, anti-inflammatory, anti-angiogenic, and anti-proliferative effects. The main limitation of in vivo studies is the complexity of isolating the effects related to each one of the nutrients and the relationship with other possible etiological mechanisms. On the contrary, in vitro studies allow determining the specific mechanisms of action of some of the dietary compounds. In conclusion, and despite research limitations, the beneficial effects of a diet rich in vegetables and fruits are attributed to different micronutrients that are also found in fish and animal products. These compounds show antioxidant, anti-inflammatory, anti-angiogenic, and anti-proliferative properties that have a preventive role in the development of oral and other types of cancer.

Gene Polymorphisms Involved in Folate Metabolism and DNA Methylation with the Risk of Head and Neck Cancer

BACKGROUND

Folate is essential for DNA synthesis, repair, and methylation. Polymorphisms in genes associated with folate metabolism may alter these processes and, consequently, modulate cancer development.

AIM

We aimed to assess DNMT3B -149C/T (rs2424913), DNMT3B -283T/C (rs6087990), DNMT3B -579G/T (rs2424909), DHFR 19-pb ins/del (rs70991108), SHMT1 1420C/T (rs1979277), and TYMS 28-bp tandem repeat (rs34743033) polymorphisms with risk of head and neck cancer.

METHODS

A case-control study was conducted in 1,086 Brazilian individuals. Real-time and conventional polymerase chain reactions-PCR were performed for genotyping the polymorphisms.

RESULTS

The single nucleotide polymorphism (SNP), DNMT3B -283T/C, revealed a higher risk of head and neck squamous cell carcinoma (HNSCC) when compared with the C group in the codominant (p < 0.001), dominant (p <0.001), and overdominant (p= 0.001) models for T/C and C/C genotypes. DNMT3B -149C/T and DNMT3B -579G/T revealed no association between groups in any model. The DHFR 19-pb ins/del polymorphism protected against HNSCC development compared to the C group by the codominant (p < 0.001), dominant (p < 0.001), and overdominant (p < 0.001) models. In the TYMS, the 3R/3R genotype had a protective effect against HNSCC development compared with the C group by the recessive models (p= 0.009). In contrast, SHMT1 1420 C/T presented no association between the HNSCC and C groups. DHFR 19-pb ins/del polymorphisms protected against oral cavity cancer (p= 0.003), and only TYMS-28 3R/3R decreased the risk of tumor progression (p= 0.023). In the Kaplan-Meier curve, an association was found between DHFR ins/ins and TYMS -28 3R carriers with respect to relapse-free time; further, DNMT3B -579 T and TYMS-28 2R/2R carriers had longer survival times.

CONCLUSION

DNMT3B -283T/C is associated with higher risk, whereas DHFR 19-pb ins/del and TYMS 28 3R/3R protect against head and neck cancer. We also highlighted the association of TYMS 3R/3R genotype carriers with relapse-free cancer protection and survival time.

Metformin inhibits epithelial-mesenchymal transition of oral squamous cell carcinoma via the mTOR/HIF-1α/PKM2/STAT3 pathway

Epithelial-mesenchymal transition (EMT) serves an important role in the formation and development of various types of cancer, including oral squamous cell carcinoma (OSCC). Metformin, used for treating type 2 diabetes, has been revealed to exert an anticancer effect in various types of cancer, including liver, breast and colorectal cancer. However, its role in the EMT of OSCC has been rarely reported. Therefore, the present study aimed to investigate the effects of metformin on EMT and to identify its underlying mechanism in OSCC. Firstly, EMT was induced in CAL-27 cells using CoCl₂. Subsequently, the effects of metformin on cell viability, migration and xenograft growth were evaluated in vitro and in vivo. Reverse transcription-quantitative PCR was performed to detect the expression levels of E-cadherin, vimentin, snail family transcriptional repressor 1, mTOR, hypoxia inducible factor 1α, pyruvate kinase M2 and STAT3. The results demonstrated that metformin abolished CoCl₂-induced cell proliferation, migration, invasion and EMT. Moreover, metformin reversed EMT in OSCC by inhibiting the mTOR-associated HIF-1α/PKM2/STAT3 signaling pathway. Overall, the present findings characterized a novel mechanism via which metformin modulated EMT in OSCC.

Epidemiology of head and neck cancers: an update

PURPOSE OF REVIEW

This review attempts to give an update of epidemiological knowledge on head and neck cancers (HNC).

RECENT FINDINGS

Worldwide, from 1990 to 2017, incidence rates for larynx and nasopharyngeal cancers decreased, whereas they increased for oro/hypopharyngeal cancers and lip/oral cavity cancers. They are still markedly higher among men than women. South Asia has the highest HNC incidence rate, followed by Europe, North America, and Australasia.Tobacco and alcohol remain the major risk factors. Rate of cancers attributable to human papillomavirus (HPV) among HNCs is highly depending on world region and tobacco use prevalence. It increases in high-income countries. In the US population, the number of HPV-attributable oropharyngeal cancers now exceeds the number of cervix cancers. HPV vaccination for boys is recommended in an increasing number of countries. Many occupations are associated with an increased HNC risk. Fruits and vegetables intake have a protective effect against HNC.

SUMMARY

To decrease HNC incidence, measures to reduce tobacco use and alcohol consumption remain essential. Improvement of HPV vaccination coverage is also a major objective. Reduction of carcinogens at occupation, protection of workers from carcinogen exposures, education for better diet, and easy and affordable access to fruits and vegetables can contribute to incidence decrease.

Folate pathways mediating the effects of ethanol in tumorigenesis

Folate and alcohol are dietary factors affecting the risk of cancer development in humans. The interaction between folate status and alcohol consumption in carcinogenesis involves multiple mechanisms. Alcoholism is typically associated with folate deficiency due to reduced dietary folate intake. Heavy alcohol consumption also decreases folate absorption, enhances urinary folate excretion and inhibits enzymes pivotal for one-carbon metabolism. While folate metabolism is involved in several key biochemical pathways, aberrant DNA methylation, due to the deficiency of methyl donors, is considered as a common downstream target of the folate-mediated effects of ethanol. The negative effects of low intakes of nutrients that provide dietary methyl groups, with high intakes of alcohol are additive in general. For example, low methionine, low-folate diets coupled with alcohol consumption could increase the risk for colorectal cancer in men. To counteract the negative effects of alcohol consumption, increased intake of nutrients, such as folate, providing dietary methyl groups is generally recommended. Here mechanisms involving dietary folate and folate metabolism in cancer disease, as well as links between these mechanisms and alcohol effects, are discussed. These mechanisms include direct effects on folate pathways and indirect mediation by oxidative stress, hypoxia, and microRNAs.

Association between dietary inflammatory index and upper aerodigestive tract cancer risk: A systematic review and dose-response meta-analysis

OBJECTIVES

The relationship between dietary inflammatory index (DII) and upper aerodigestive tract (UADT) cancer risk have been investigated in a growing number of epidemiological studies. However, their findings were inconsistent, and no systematic review or meta-analysis has been conducted up to now. This meta-analysis was carried out to examine potential dose-response relationship between DII score and UADT cancer risk.

MATERIAL AND METHODS

A systematic search was conducted for relevant studies in PubMed and Web of Science up to March 28, 2019. Categorical meta-analysis as well as linear and non-linear dose-response meta-analysis were performed to evaluate association between DII and UADT cancer risk.

RESULTS

Nine case-control studies with a total of 4138 cases and 15,326 healthy controls were eligible in the present meta-analysis. The pooled odds ratios (ORs) of UADT cancer risk were 2.07 [95% confidence interval (CI): 1.82, 2.35] for the highest DII score compared with the lowest and 1.53 (95% CI: 1.39, 1.69) for higher DII score compared with lower score, respectively. Furthermore, a one-unit increment in DII score was associated with an increased risk of 18% for UADT cancers (OR: 1.18; 95% CI: 1.15, 1.21). An upward trend towards a positive association between elevated DII score and UADT cancer risk was also observed in non-linear dose-response meta-analysis.

CONCLUSIONS

The present meta-analysis provides evidence of highly pro-inflammatory diets that might increase risk of UADT cancers. Therefore, reducing pro-inflammatory components in diets should be considered to prevent and control UADT cancers.

Folate and Its Impact on Cancer Risk

PURPOSE OF REVIEW

Research has evaluated the potential impact of folate on cancer risk with conflicting findings. Studies have demonstrated increased risk, no effect, and decreased risk. This review summarizes findings of mixed results between folate intake, serum levels, gene polymorphisms, and cancer risk based on meta-analyses from the past five years.

RECENT FINDING

Low or deficient folate status is associated with increased risk of many cancers. Folic acid supplementation and higher serum levels are associated with increased risk of prostate cancer. Gene polymorphisms may impact risk in certain ethnic groups. Folate has been studied extensively due to its role in methylation and nucleotide synthesis. Further prospective studies are needed to clarify optimal levels for nutrient remediation and risk reduction in those at risk, as well as elucidate the association between high intake, high serum levels, and prostate cancer risk. Future considerations for cancer risk may include gene interactions with nutrients and environmental factors.

Role of Key Micronutrients from Nutrigenetic and Nutrigenomic Perspectives in Cancer Prevention

Regarding cancer as a genetic multi-factorial disease, a number of aspects need to be investigated and analyzed in terms of cancer's predisposition, development and prognosis. One of these multi-dimensional factors, which has gained increased attention in the oncological field due to its unelucidated role in risk assessment for cancer, is diet. Moreover, as studies advance, a clearer connection between diet and the molecular alteration of patients is becoming identifiable and quantifiable, thereby replacing the old general view associating specific phenotypical changes with the differential intake of nutrients. Respectively, there are two major fields concentrated on the interrelation between genome and diet: nutrigenetics and nutrigenomics. Nutrigenetics studies the effects of nutrition at the gene level, whereas nutrigenomics studies the effect of nutrients on genome and transcriptome patterns. By precisely evaluating the interaction between the genomic profile of patients and their nutrient intake, it is possible to envision a concept of personalized medicine encompassing nutrition and health care. The list of nutrients that could have an inhibitory effect on cancer development is quite extensive, with evidence in the scientific literature. The administration of these nutrients showed significant results in vitro and in vivo regarding cancer inhibition, although more studies regarding administration in effective doses in actual patients need to be done.

Fish/shellfish intake and the risk of head and neck cancer

Fish intake and other dietary sources of omega-3 fatty acids have been shown to be associated with a reduced risk for some cancers. Although previous studies of head and neck cancer have reported associations with different dietary factors, including reduced risks for fruits and vegetables and putatively healthy dietary patterns, associations specific to fish intake are unclear. This study investigated the association between fish/shellfish intake and risk of squamous cell carcinoma of the head and neck (SCCHN) using data from the Carolina Head and Neck Cancer Epidemiology Study, a population-based case-control study conducted in 46 North Carolina counties with cases recruited from 2002 through 2006. Controls were frequency matched to the cases on age, sex, and race; the final sample size was 1039 cases and 1375 controls. Demographic, lifestyle, and dietary information were collected using an in-person interviewer-administered structured questionnaire. Multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated with unconditional logistic regression. Patients whose fish/shellfish intake was among the highest tertile had a 20% lower odds of SCCHN compared with those in the lowest tertile (OR: 0.80; 95% CI: 0.60-1.07) after adjustment for the matching and other factors (income, energy intake, fruit intake, cigarette smoking, and alcohol intake). The inverse association was more pronounced for oral cavity and oropharyngeal tumors, for African Americans, and for females, but CIs were wide. To further investigate this potential risk reduction strategy for SCCHN, future studies should consider examining specific fish/shellfish, cooking practices, and other omega-3 fatty acid sources.

Maternal folic acid depletion during early pregnancy increases sensitivity to squamous tumor formation in the offspring in mice

Gestational nutrition is widely recognized to affect an offspring's future risk of lifestyle-related diseases, suggesting the involvement of epigenetic mechanisms. As folic acid (FA) is a nutrient essential for modulating DNA methylation, we sought to determine how maternal FA intake during early pregnancy might influence tumor sensitivity in an offspring. Dams were maintained on a FA-depleted (FA(-)) or normal (2 mg FA/kg; FA(+)) diet from 2 to 3 days before mating to 7 days post-conception, and their offspring were challenged with chemical tumorigenesis using 7,12-dimethylbenz[a)anthracene and phorbol 12-myristate 13-acetate for skin and 4-nitroquinoline N-oxide for tongue. In both squamous tissues, tumorigenesis was more progressive in the offspring from FA(-) than FA(+) dams. Notably, in the skin of FA(-) offspring, the expression and activity of cylindromatosis (Cyld) were decreased due to the altered DNA methylation status in its promoter region, which contributed to increased tumorigenesis coupled with inflammation in the FA(-) offspring. Thus, we conclude that maternal FA insufficiency during early pregnancy is able to promote neoplasm progression in the offspring through modulating DNA methylation, such as Cyld. Moreover, we propose, for the first time, "innate" utero nutrition as the third cause of tumorigenesis besides the known causes-hereditary predisposition and acquired environmental factors.

Association between coffee intake and the risk of oral cavity cancer: a meta-analysis of observational studies

The association between coffee intake and the risk of oral cavity cancer has been inconsistent in previous studies. Therefore, we conducted a meta-analysis to summarize the evidence regarding the strength of association between coffee intake and oral cavity cancer. PubMed, Embase, and Cochrane Library were searched to select studies on the relationship between coffee intake and oral cavity cancer conducted up to September 2018. Case-control or cohort studies and those that have reported about the effect estimates with 95% confidence intervals (CIs) of oral cavity cancer according to the different categories of coffee intake were included. The odds ratio (OR) and its corresponding 95% CI were calculated using the random-effects model. Fourteen case-control and five cohort studies that recruited 6456 patients with oral cavity cancer were included in the final quantitative meta-analysis. High versus low coffee intake was associated with a reduced risk of oral cavity cancer (OR: 0.68; 95% CI: 0.56-0.82; P < 0.001) in case-control studies (OR: 0.70; 95% CI: 0.55-0.90; P = 0.006) and cohort studies (OR: 0.65; 95% CI: 0.48-0.87; P = 0.004). Moreover, intermediate coffee intake was significantly associated with a reduced risk of oral cavity cancer (OR: 0.85; 95% CI: 0.77-0.94; P = 0.002), and such associations were mainly observed in case-control studies (OR: 0.86; 95% CI: 0.76-0.98; P = 0.021) but not in cohort studies (OR: 0.83; 95% CI: 0.67-1.02; P = 0.071). High or intermediate coffee intake might have protective effects against oral cavity cancer. However, the underlying mechanisms must be further evaluated in large-scale prospective cohort studies.

Decreased expression of folate transport proteins in oral cancer

OBJECTIVES

The purpose of this study was to assess the expression of the 3 major folate transporters-folate receptors (FRs), reduced folate carrier (RFC), and proton-coupled folate transporter (PCFT)-in oral squamous cell carcinoma (OSCC). We hypothesized that patterns of expression of folate transporters would be different in OSCC compared with normal oral epithelium.

STUDY DESIGN

We used immunohistochemistry to examine the expression of FR, RFC, and PCFT in 15 primary specimens collected from patients with OSCC, 2 human cadaveric samples of OSCC, and 12 normal human cadaveric oral tissues from a medical gross anatomy laboratory. Possible correlations between the expression of each folate transporter and patients' clinical data were determined.

RESULTS

All 3 folate transporters were highly expressed in normal oral epithelium. In contrast, OSCC samples generally demonstrated low expression of FR, RFC, and PCFT, with wide distribution in the invading cancer cells. There were no differences in folate transporter expression between OSCC samples collected from patients and from human cadavers. The lowest expression of FR and PCFT characterized less-differentiated tumors, and the lowest expression of RFC correlated with higher lymph node involvement.

CONCLUSIONS

Human oral cancer samples expressed decreased amounts of all 3 major folate transport proteins compared with controls from normal cadaveric oral tissues.

Dietary Fatty Acids and Other Nutrients in Relation to Inflammation and Particularly to Oral Mucosa Inflammation. A Literature Review

Oral mucosa is site of inflammatory process development. When they are chronic, they provide a microenvironment based on cytokines and inflammatory mediators that contribute to cancer initiation, progression, invasion, and metastasis. Certain dietary fatty acids (FAs) have immunomodulatory, inflammatory, and antiinflammatory effects. This review examined the literature on inflammation, mainly referred to the oral mucosa, and its association with dietary FAs and other nutrients. A Pubmed search of studies published in English until June 2018 was carried out. N-3 FAs have shown immunomodulatory and antiinflammatory activity in certain human diseases. These FAs and their mediators may inhibit inflammation, angiogenesis, and cancer via multiple mechanisms. Studies on cellular models of murine and human intestinal mucosa indicate association between dietary n-3 FA intake and the inflammatory state of mucosa membranes. Nevertheless scarce information on the association between dietary FAs and oral inflammation could be found. Based on the evidence, we hypothesize that n-3 FAs reduce the oral mucosa inflammation thus decreasing the risk of developing precancerous lesions and cancer. Molecular and clinical studies referred to this topic should be carried out as a contribution to the oral cancer prevention.

Micronutrient Intake and Risk of Hematological Malignancies in Adults: A Systematic Review and Meta-analysis of Cohort Studies

There has been accumulating evidence that several micronutrients may play a protective role in the risk of solid cancers. However, their role in hematological malignancies remains to be elucidated; this meta-analysis aims to evaluate the associations between micronutrient intake as well as supplementation and risk of hematological cancer in adults. Eligible cohort studies (examining intake of vitamin A, vitamin C, vitamin D, vitamin E, lycopene, folate, iron, carotenoids, beta-carotene, selenium, pyridoxine) were sought in PubMed up to July 31, 2016. Random-effects models were used for the calculation of pooled relative risks (RR) with their 95% confidence intervals (CI). Twelve cohort studies were deemed eligible. Null associations were noted regarding supplemented vitamin A (pooled relative risk [RR] = 0.92, 95% confidence interval [CI]: 0.80-1.07), supplemented vitamin C (pooled RR = 1.00, 95%CI: 0.90-1.12), total vitamin D (pooled RR = 1.05, 95%CI: 0.91-1.20), supplemented vitamin E (pooled RR = 0.98, 95%CI: 0.88-1.10), and dietary lycopene intake (pooled RR = 1.00, 95%CI: 0.86-1.16) and the risk of non-Hodgkin lymphoma. No summary estimates are provided for other hematological malignancies due to the limited number of studies. Future prospective trials should be conducted for a better understanding of this field; especially regarding Hodgkin lymphoma, leukemia and plasma cell neoplasms, on which data are scarce.

Identifying Risk Factors for Morbidity and Mortality in Patients with Primary Head and Neck Cancers in a Nigerian Population

Background

The risk factors for head and neck cancers (HNC) vary in different parts of the world.

Objectives

To identify the risk factors for HNC and the correlation between these factors and the involved anatomical sites.

Methods

We retrieved and analyzed health records of patients that met the inclusion criteria for HNC managed at our facility in a 10-year period using the International Classification of Diseases (ICD) version 10.

Results

We studied 122 patients with a male to female ratio of 2.1:1 aged 13 years to 85 years (mean = 51 years). Alcohol (P = .02), cigarette smoking (P = .01), and cooking wood smoke (P = .01) were associated with advanced tumor stage.

Conclusions

The strongest risk factors for HNC are alcohol, tobacco, HIV, agricultural chemicals, and cooking wood fumes in both sexes in their sixth and seventh decades.

Proinflammatory diet is associated with increased risk of squamous cell head and neck cancer

Diets high in fruits and vegetables and low in red meat intake have been associated with decreased risk of head and neck cancer. Additionally, chronic inflammation pathways and their association with cancer have been widely described. We hypothesized a proinflammatory diet, as measured by the dietary inflammatory index (DII^® ), is associated with increased risk of head and neck cancer. We used the Carolina Head and Neck Cancer (CHANCE) study, a population-based case-control study of head and neck squamous cell carcinoma. Cases were recruited from a 46-county region in central North Carolina. Controls, frequency-matched on age, race, and sex were identified through the North Carolina Department of Motor Vehicle records. The DII score, adjusted for energy using the density approach (E-DII), was calculated from a food frequency questionnaire and split into four quartiles based on the distribution among controls. Adjusted odds ratios (ORs) were estimated with unconditional logistic regression. Cases had higher E-DII scores (i.e., a more proinflammatory diet) compared with controls (mean: -0.14 vs. -1.50; p value < 0.001). When compared with the lowest quartile, the OR for the highest quartile was 2.91 (95% confidence interval (CI): 2.16-3.95), followed by 1.93 (95% CI: 1.43-2.62) for the third quartile, and 1.37 (95% CI: 1.00-1.89) for the second quartile. Both alcohol and smoking had a significant additive interaction with E-DII (smoking relative excess risk due to interaction (RERI): 2.83; 95% CI: 1.36-4.30 and alcohol RERI: 1.75; 95% CI: 0.77-2.75). These results provide additional evidence for the association between proinflammatory diet and head and neck cancer.

Association between Mediterranean diet and head and neck cancer: results of a large case-control study in Italy

The Mediterranean diet (MD) is a known protective factor for head and neck cancer (HNC); however, there is still a lack of studies investigating this association by HNC subsite. The aim of the present study was therefore to evaluate the association between adherence to MD and HNC overall and by cancer subsite, as well as the effect of the individual food components on HNC risk. A case-control study was carried out at the Gemelli Hospital of Rome (Italy). A total of 500 HNC cases and 433 controls were interviewed. Dietary intake was assessed through a validated food frequency questionnaire that collected information on over 25 food items. Odds ratios (ORs) and 95% confidence intervals (CI) of HNC were calculated using a multiple logistic regression model. We found a reduced risk of both oral cavity and pharynx cancer (OR=0.61; CI: 0.54-0.70) and larynx cancer (OR=0.64; CI: 0.56-0.73) with increasing adherence to MD. We also found a high consumption of fruit, vegetables, and legumes to be significantly associated with a lower risk of larynx as well as oral cavity and pharynx cancers. Our study showed that adherence to MD acts protectively against HNC overall and by cancer subsite.

The Health System and Policy Implications of Changing Epidemiology for Oral Cavity and Oropharyngeal Cancers in the United States From 1995 to 2016

Oral cavity and oropharyngeal cancers are typically grouped under the general term, "oral cancer." Yet, the incidence of oropharyngeal cancers is increasing in the United States, while the incidence of oral cavity cancers has declined. These 2 distinct but conflated groups of oral cancers are attributed to different risk factors. Incidence and survival trends were examined across US population groups and by anatomical subsite. Disparities in incidence and survival by sex, race/ethnicity, and subsite were identified. Risk factors are complex, interactive, and not fully identified. Cancer control research illustrates health disparities in access to care and patient outcomes. Database and supplemental searches yielded 433 articles published between 1995 and 2016 characterizing aspects of oral cancer epidemiology relating to incidence, survival, risk, disparities, and cancer control. Oral cavity cancer survival in black men remains the most intractable burden. Although understanding of oral cancer etiology is improving, application to policy is limited. Cancer control efforts are diverse, sporadic, limited in scope, and generally lacking in success, and they need stratification by oral cavity cancers/oropharyngeal cancers. Further intervention and epidemiologic research, improved workforce capacity, and integrated care delivery are identified as important directions for public health policy. Sustained, multilevel campaigns modeled on tobacco control success are suggested.

Prognostic factors in head and neck cancer: a 10-year retrospective analysis in a single-institution in Italy

This study was undertaken to evaluate the association between demographics, lifestyle habits, and clinical data and overall survival (OS), recurrence and second primary cancer (SPC) in patients with first primary head and neck cancer (HNC). We retrospectively reviewed data from 482 patients treated at the "Agostino Gemelli" Teaching Hospital, Rome, between 2002-2012 for primary HNC. Individual parameters were evaluated for association with specific outcomes such as OS, cancer recurrence and second primary cancer (SPC) appearance using hazard ratios (HR) and 95% confidence intervals (CIs). Five-year OS was 60.6% for all HNC cases, 49.0% for oral cavity, 54.8% for oropharynx, 50.0% for hypopharynx and 63.4% for larynx. Predictors of OS were older age (HR = 1.04; 95% CI: 1.02-1.05) and advanced tumour stage (HR = 2.00; 95% CI: 1.41-2.84). The risk of recurrence was associated with drinking 8-14 drinks per week (HR = 1.73; 95% CI: 1.00-2.97). The risk of developing SPC increased with advanced tumour stage (HR = 2.75; 95% CI: 1.39-5.44) and with smoking for more than 40 years (HR = 3.68; 95% CI: 1.10-12.30). OS differed among HNC sites. Increasing age was an unfavourable predictor of HNC OS. Tumour stage was a prognostic factor both for OS and for risk of developing SPC. Alcohol and tobacco consumption were prognostic factors for recurrence and SPC, respectively.

Associations between oral hygiene habits, diet, tobacco and alcohol and risk of oral cancer: A case-control study from India

OBJECTIVE

This study examines the association between the incidence of oral cancer in India and oral hygiene habits, diet, chewing and smoking tobacco, and drinking alcohol. We also assessed the effects of oral hygiene habits with oral cancer risk among chewers versus never chewers.

METHODS

A hospital-based case-control study was conducted in Pune, India, based on face-to-face interviews, anthropometry, and intra-oral examinations conducted for 187 oral cancer cases and 240 controls.

RESULTS

Poor oral hygiene score was associated with a significant risk of oral cancer (adjusted OR=6.98; 95%CI 3.72-13.05). When stratified by tobacco-chewing habit, the poor oral hygiene score was a significant risk factor only among ever tobacco chewers (adjusted OR=14.74; 95%CI 6.49-33.46) compared with never chewers (adjusted OR=0.71; 95%CI 0.14-3.63). Dental check-ups only at the time of pain by ever-chewers with poor oral hygiene was associated with an elevated risk (adjusted OR=4.22; 95%CI 2.44-7.29), while consumption of green, yellow, and cruciferous vegetables and citrus fruits was protective. A linear dose-response association was observed between oral cancer and chewing tobacco in terms of age at initiation, duration, and frequency of chewing per day (P<0.001). Smoking more than 10 bidis/cigarettes per day (adjusted OR=2.74; 95%CI 1.28-5.89) and for a duration >25 years (adjusted OR=2.31; 95%CI 1.14-4.71) elevated the risk of oral cancer.

CONCLUSION

Good oral hygiene habits - as characterized by healthy gums, brushing more than once daily, use of toothpaste, annual dental check-ups, and a minimal number of missing teeth - can reduce the risk of oral cancer significantly. In addition to refraining from chewing/smoking tobacco, a diet adequate in fruits and vegetables may protect against the disease.

The impact of folate intake on the risk of head and neck cancer in the prostate, lung, colorectal, and ovarian cancer screening trial (PLCO) cohort

BACKGROUND

Although low levels of folate leads to disturbances in DNA replication, DNA methylation and DNA repair, the association between dietary folate intake and head and neck cancer (HNC) risk remains unclear.

METHODS

We evaluated the association between folate intake and HNC risk using prospective cohort data from the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial. This study included 101 700 participants and 186 cases with confirmed incident HNC. The median follow-up was 12.5 years. We estimated hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) using Cox proportional hazard model including age, sex, body mass index, education, race, tobacco smoking, alcohol drinking and total fruit and vegetable intake.

RESULTS

Higher intake of food folate and fortified folic acid in foods was associated with a decreasing HNC risk in a dose-response manner. The HRs of highest vs the lowest quartile of intake were 0.35 (95%CI: 0.18-0.67) for food folate, and 0.49 (95%CI: 0.30-0.82) for fortified folic acid. Intakes of total folate, natural folate and supplemental folic acid were not associated with the risk of HNC and its subsites. We did not detect any interaction between smoking, drinking and food folate intake on HNC risk.

CONCLUSIONS

These findings provide evidence of the protective role of dietary folate intake on HNC risk.

Dietary fiber intake and head and neck cancer risk: A pooled analysis in the International Head and Neck Cancer Epidemiology consortium

The possible role of dietary fiber in the etiology of head neck cancers (HNCs) is unclear. We used individual-level pooled data from ten case-control studies (5959 cases and 12,248 controls) participating in the International Head and Neck Cancer Epidemiology (INHANCE) consortium, to examine the association between fiber intake and cancer of the oral cavity/pharynx and larynx. Odds Ratios (ORs) and their 95% Confidence Intervals (CIs) were estimated using unconditional multiple logistic regression applied to quintile categories of non-alcohol energy-adjusted fiber intake and adjusted for tobacco and alcohol use and other known or putative confounders. Fiber intake was inversely associated with oral and pharyngeal cancer combined (OR for 5th vs. 1st quintile category = 0.49, 95% CI: 0.40-0.59; p for trend <0.001) and with laryngeal cancer (OR = 0.66, 95% CI: 0.54-0.82, p for trend <0.001). There was, however, appreciable heterogeneity of the estimated effect across studies for oral and pharyngeal cancer combined. Nonetheless, inverse associations were consistently observed for the subsites of oral and pharyngeal cancers and within most strata of the considered covariates, for both cancer sites. Our findings from a multicenter large-scale pooled analysis suggest that, although in the presence of between-study heterogeneity, a greater intake of fiber may lower HNC risk.

miR-222 knockdown suppresses epithelial-to-mesenchymal transitionin human oral squamous cell carcinoma

Tumor metastasis is the main cause of death in patients with oral squamous cell carcinoma (OSCC). Epithelial-to-mesenchymal transition (EMT) is potentially associated with metastasis and histological grading in OSCC. Therefore, the discovery of new strategies to inhibit EMT is potentially valuable for the development of therapies for OSCC. In our previous study, we found that miR-222, which is up-regulated in OSCC, regulates the biological behavior of OSCC cells by targeting the p53-upregulated modulator of apoptosis (PUMA); however, the effect of miR-222 on TGF-β1-induced EMT in OSCC cells is unclear. In this study, OSCC cell lines CAL-27 and Tca-8113 were incubated with 5 ng/ml of TGF-β1 to inhibit the expression of E-cadherin, promote the expression of N-cadherin, vimentin, and α-SMA and stimulate achange in cell shape convert from a "cuboidal" epithelial structure into an elongated mesenchymal shape. We found that the expression of miR-222 was up-regulated during TGF-β1-induced EMT in OSCC cells. In addition, miR-222 knockdown reversed TGF-β1-induced EMT by targeting PUMA. Our findings indicate that miR-222 plays an important role in OSCC, potentially serving as a novel therapeutic target for the treatment of OSCC.

Association between folate intake and risk of head and neck squamous cell carcinoma: An overall and dose-response PRISMA meta-analysis

The results of published studies about the relationships between folate intake and risk of head and neck squamous cell carcinoma (HNSCC) remained inconsistent. Hence, a comprehensive and dose-response meta-analysis was performed to clarify the association between folate intake and HNSCC risk.The electric searches of Pubmed, Medline, and EMBASE databases were performed to identify the studies examining the relationship between folate intake and HNSCC risk on April 5, 2017. According to the inclusion criteria, finally 9 studies were included in this meta-analysis. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the strength of associations. Dose-response analysis was conducted to quantitate the relationship between dietary folate intake and HNSCC risk.The pooled OR for assessing the risk of HNSCC and folate intake in the highest level versus lowest level was 0.505 (95% CI 0.387-0.623). The linearity model of dose-response analysis indicated that with increased 100 μg/d folate intake, the risk of HNSCC decreased 4.3% degree (OR 0.957, 95% CI 0.935-0.980).These results indicate that folate is a protective nutrient against HNSCC carcinogenesis.

Inflammatory potential of diet and risk of oral and pharyngeal cancer in a large case-control study from Italy

Diet and inflammation have been suggested to be important risk factors for oral and pharyngeal cancer. We examined the association between dietary inflammatory index (DII™) and oral and pharyngeal cancer in a large case-control study conducted between 1992 and 2009 in Italy. This study included 946 cases with incident, histologically confirmed oral and pharyngeal cancer, and 2,492 controls hospitalized for acute non-neoplastic diseases. The DII was computed based on dietary intake assessed by a valid 78-item food frequency questionnaire and was adjusted for nonalcohol energy intake using the residual approach (E-DII™). Logistic regression models were used to estimate odds ratios (ORs), and 95% confidence intervals (CIs), adjusted for age, sex, non-alcohol energy intake, study center, year of interview, education, body mass index, tobacco smoking, and alcohol drinking. Subjects with higher DII scores (i.e., with a more pro-inflammatory diet) had a higher risk of oral and pharyngeal cancer, the OR being 1.80 (95% CI 1.36-2.38) for the highest versus the lowest DII quartile and 1.17 (95% CI 1.10-1.25) for a one-unit increase (8% of the DII range). When stratified by selected covariates, a stronger association was observed among women (OR_{quartile4 v.1} 3.30, 95% CI 1.95-5.57). We also observed a stronger association for oral cancers and a strong combined effect of higher DII score and tobacco smoking or alcohol consumption on oral and pharyngeal cancer. These results indicate that the pro-inflammatory potential of the diet, as shown by higher DII scores, is associated with higher odds of oral and pharyngeal cancer.

Head and Neck Cancers in North-East Iran: A 25 year Survey

INTRODUCTION

Cancers are among the worst noncommunicable diseases around the world. Head and neck cancers are ranked as the fifth most common cancers worldwide. As there are different distributions of risk factors around the world, the incidence of these cancers varies from one place to another.

MATERIALS AND METHODS

We conducted a descriptive analytic cross-sectional study, based on census-based records from the private oncology clinic in Mashhad, Iran. Data from 1,075 patients with head and neck cancers were analyzed from 1986 to 2010. We categorized the duration of study into five periods: 1986-1990, 1991-1995, 1996-2000, 2001-2005, and 2006-2010. Head and neck cancers refers to cancers originating from seven sites in the head and neck including the nasal cavity, oral cavity, pharynx, larynx, salivary glands, paranasal sinuses, and thyroid.

RESULTS

Data of 1,075 patients were analyzed. 66.2% were male. Mean ± standard deviation (SD) age at the time of diagnosis was 55.37±15.55 years. The most frequent type of head and neck cancer was larynx cancer (36%), followed by pharynx (28.5%), oral (17.5%), thyroid (6.8%), sinus (6.4%), salivary gland (4.10%), and nasal cancer (0.70%). although larynx cancer was the most frequent cancer over the whole study duration, there was a significant (P=0.04) difference in the relative frequency of these cancers across the five time periods. There was a significant difference in mean age between cancer categories (P<0.001). The only cancer with a different mean age at different time periods was pharynx cancer (P=0.02). There was a significant difference between sex and cancer categories (P<0.001).

CONCLUSION

Laryngeal cancer was the most common head and neck cancer over the whole duration of this study. The differences in the patterns of other head and neck cancers could be due to geographical differences and also different risk factors and lifestyles all over the world. Further investigations in these fields are suggested in future studies.

Effect of vitamin B supplementation on cancer incidence, death due to cancer, and total mortality: A PRISMA-compliant cumulative meta-analysis of randomized controlled trials

BACKGROUND

Observational studies have suggested that vitamin B supplementation is associated with cancer risk, but this association remains controversial. A pooled data-based meta-analysis was conducted to summarize the evidence from randomized controlled trials (RCTs) investigating the effects of vitamin B supplementation on cancer incidence, death due to cancer, and total mortality.

METHODS

PubMed, EmBase, and the Cochrane Library databases were searched to identify trials to fit our analysis through August 2015. Relative risk (RR) was used to measure the effect of vitamin B supplementation on the risk of cancer incidence, death due to cancer, and total mortality using a random-effect model. Cumulative meta-analysis, sensitivity analysis, subgroup analysis, heterogeneity tests, and tests for publication bias were also conducted.

RESULTS

Eighteen RCTs reporting the data on 74,498 individuals were included in the meta-analysis. Sixteen of these trials included 4103 cases of cancer; in 6 trials, 731 cancer-related deaths occurred; and in 15 trials, 7046 deaths occurred. Vitamin B supplementation had little or no effect on the incidence of cancer (RR: 1.04; 95% confidence interval [CI]: 0.98-1.10; P = 0.216), death due to cancer (RR, 1.05; 95% CI: 0.90-1.22; P = 0.521), and total mortality (RR, 1.00; 95% CI: 0.94-1.06; P = 0.952). Upon performing a cumulative meta-analysis for cancer incidence, death due to cancer, and total mortality, the nonsignificance of the effect of vitamin B persisted. With respect to specific types of cancer, vitamin B supplementation significantly reduced the risk of skin melanoma (RR, 0.47; 95% CI: 0.23-0.94; P = 0.032).

CONCLUSION

Vitamin B supplementation does not have an effect on cancer incidence, death due to cancer, or total mortality. It is associated with a lower risk of skin melanoma, but has no effect on other cancers.

Proapoptotic Activity of Propolis and Their Components on Human Tongue Squamous Cell Carcinoma Cell Line (CAL-27)

Propolis has been used since ancient times in folk medicine. It is a popular medicine possessing a broad spectrum of biological activities. This material is one of the richest sources of polyphenolic compounds such as flavonoids and phenolic acids. The ethanolic extract of propolis (EEP) evokes antibacterial, antiviral, antifungal and anticancer properties. Due to pharmacological properties it is used in the commercial production of nutritional supplements. In this study, gas chromatography coupled with mass spectrometry (GC-MS) was used to quantify main polyphenols in EEPs. The effect of EEPs, individual EEPs components (chrysin, galangin, pinocembrin, caffeic acid, p-coumaric acid, ferulic acid) and their mixture on viability of human tongue squamous cell carcinoma cell line (CAL-27) as well as the molecular mechanisms of the process were examined. The results of MTTs assay demonstrated that EEP, polyphenols and mixture of polyphenolic compounds were cytotoxic for CAL-27 cells in a dose dependent manner. The mechanism of cytotoxicity induced by these components undergoes through apoptosis as detected by flow cytometry. The ethanolic extracts of propolis activated caspases -3, -8, -9. Mixture of polyphenols was found as the most potent inducer of apoptosis thorough both intrinsic and extrinsic pathway. Therefore, we suggest that anticancer properties of propolis is related to synergistic activity of its main components.

Folate, vitamin B6, vitamin B12 and methionine intakes and risk for nasopharyngeal carcinoma in Chinese adults: a matched case-control study

Many studies have suggested that folate-related one-carbon metabolism-related nutrients may play a role in certain cancer risks, but few studies have assessed their associations with the risk for nasopharyngeal carcinoma (NPC). In this study, we investigated the association between four folate-related one-carbon metabolism-related nutrients (folate, vitamin B6, vitamin B12 and methionine) and NPC risk in Chinese adults. A total of 600 patients newly diagnosed (within 3 months) with NPC were individually matched with 600 hospital-based controls by age, sex and household type (urban v. rural). Folate, vitamin B6, vitamin B12 and methionine intakes were measured using a validated seventy-eight-item FFQ. A higher dietary folate or vitamin B6 intake was associated with a lower NPC risk after adjusting for potential confounders. The adjusted OR of NPC for quartiles 2-4 (v. 1) were 0·66 (95% CI 0·48, 0·91), 0·52 (95% CI 0·37, 0·74) and 0·34 (95% CI 0·23, 0·50) (P(trend)<0·001) for folate and 0·72 (95% CI 0·52, 1·00), 0·55 (95% CI 0·39, 0·78) and 0·44 (95% CI 0·30, 0·63) (P(trend)<0·001) for vitamin B6. No significant association with NPC risk was observed for dietary vitamin B12 or methionine intake. The risk for NPC with dietary folate intake was more evident in the participants who were not exposed to toxic substances than in those who were exposed (P(interaction)=0·014). This study suggests that dietary folate and vitamin B6 may be protective for NPC in a high-risk population.

One-Carbon Metabolic Factors and Risk of Renal Cell Cancer: A Meta-Analysis

BACKGROUND

Nutrients related to one-carbon metabolism were previously shown to be significantly associated with the risk of cancer. The aim of this meta-analysis was to evaluate potential relationships between one-carbon metabolic factors and renal cell cancer (RCC) risk.

METHODS

PubMed, EMBASE, and Cochrane Library databases were searched through March 2015 for observational studies of quantitative RCC risk estimates in relation to one-carbon metabolic factors. The relative risks (RRs) with 95% confidence intervals (CIs) measured the relationship between one-carbon metabolic factors and RCC risk using a random-effects model.

RESULTS

Of the 463 citations and abstracts identified by database search, seven cohorts from five observational studies reported data on 133,995 individuals, and included 2,441 RCC cases. Comparing the highest with the lowest category, the pooled RRs of RCC were 0.72 (95%CI: 0.52-1.00; P = 0.048) for vitamin B12. In addition, an increase in folic acid supplementation of 100 μg/day was associated with a 3% lower risk of RCC (RR, 0.97; 95%CI: 0.93-1.00; P = 0.048). Similarly, an increase of 5 nmol/L of vitamin B2 was associated with a reduced risk of RCC 0.94 (95%CI: 0.89-1.00; P = 0.045). Sensitivity analyses suggested that a higher serum vitamin B6 might contribute to a reduced risk of RCC (RR, 0.83; 95%CI: 0.77-0.89; P < 0.001).

CONCLUSIONS

Higher levels of serum vitamin B2, B6, B12, and folic acid supplementation lowered the risk of RCC among the study participants.

Vitamin E intake from natural sources and head and neck cancer risk: a pooled analysis in the International Head and Neck Cancer Epidemiology consortium

BACKGROUND

Evidence for the possible effect of vitamin E on head and neck cancers (HNCs) is limited.

METHODS

We used individual-level pooled data from 10 case-control studies (5959 cases and 12 248 controls) participating in the International Head and Neck Cancer Epidemiology (INHANCE) consortium to assess the association between vitamin E intake from natural sources and cancer of the oral cavity/pharynx and larynx. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression models applied to quintile categories of non-alcohol energy-adjusted vitamin E intake.

RESULTS

Intake of vitamin E was inversely related to oral/pharyngeal cancer (OR for the fifth vs the first quintile category=0.59, 95% CI: 0.49-0.71; P for trend <0.001) and to laryngeal cancer (OR=0.67, 95% CI: 0.54-0.83, P for trend <0.001). There was, however, appreciable heterogeneity of the estimated effect across studies for oral/pharyngeal cancer. Inverse associations were generally observed for the anatomical subsites of oral and pharyngeal cancer and within covariate strata for both sites.

CONCLUSION

Our findings suggest that greater vitamin E intake from foods may lower HNC risk, although we were not able to explain the heterogeneity observed across studies or rule out certain sources of bias.

Carotenoid intake and head and neck cancer: a pooled analysis in the International Head and Neck Cancer Epidemiology Consortium

Food and nutrition play an important role in head and neck cancer (HNC) etiology; however, the role of carotenoids remains largely undefined. We explored the relation of HNC risk with the intake of carotenoids within the International Head and Neck Cancer Epidemiology Consortium. We pooled individual-level data from 10 case-control studies conducted in Europe, North America, and Japan. The analysis included 18,207 subjects (4414 with oral and pharyngeal cancer, 1545 with laryngeal cancer, and 12,248 controls), categorized by quintiles of carotenoid intake from natural sources. Comparing the highest with the lowest quintile, the risk reduction associated with total carotenoid intake was 39 % (95 % CI 29-47 %) for oral/pharyngeal cancer and 39 % (95 % CI 24-50 %) for laryngeal cancer. Intakes of β-carotene equivalents, β-cryptoxanthin, lycopene, and lutein plus zeaxanthin were associated with at least 18 % reduction in the rate of oral and pharyngeal cancer (95 % CI 6-29 %) and 17 % reduction in the rate of laryngeal cancer (95 % CI 0-32 %). The overall protective effect of carotenoids on HNC was stronger for subjects reporting greater alcohol consumption (p < 0.05). The odds ratio for the combined effect of low carotenoid intake and high alcohol or tobacco consumption versus high carotenoid intake and low alcohol or tobacco consumption ranged from 7 (95 % CI 5-9) to 33 (95 % CI 23-49). A diet rich in carotenoids may protect against HNC. Persons with both low carotenoid intake and high tobacco or alcohol are at substantially higher risk of HNC.