Barriers to early diagnosis and management of oral cancer in Latin America and the Caribbean.

OBJECTIVE: This study aimed to explore perceived barriers to early diagnosis and management of oral cancer, as well as potential pathways for improvement in Latin America and the Caribbean (LAC). METHODS: This cross-sectional study used a self-administered online questionnaire created via the Research Electronic Data Capture platform. The survey was distributed to health professionals trained in Oral Medicine, Oral Pathology, Oral and Maxillofacial Surgery, and Dentists with clinical and academic expertise in oral potentially malignant disorder (OPMD) and oral cancer. Data obtained were systematically organized and analyzed descriptively using Microsoft Excel. RESULTS: Twenty-three professionals from 21 LAC countries participated. Major barriers included the limited implementation of OPMD and oral cancer control plans (17.4%), low compulsory reporting for OPMD (8.7%) and oral cancer (34.8%), unclear referral pathways for OPMD (34.8%) and oral cancer (43.5%), and a shortage of trained professionals (8.7%). Participants endorsed the utility of online education (100%) and telemedicine (91.3%). CONCLUSION: The survey highlights major perceived barriers to early diagnosis and management of OPMD and oral cancer in LAC, as well as potential avenues for improvement.

Unveiling the role of MGMT and DAPK hypermethylation in response to anti-EGFR agents: Molecular insights for advancing HNSCC treatment.

BACKGROUND: Epidermal growth factor receptor (EGFR) is frequently activated in head and neck squamous cell carcinoma (HNSCC) and serves as a valuable target for therapy. Despite the availability of the EGFR inhibitors Cetuximab, Afatinib, and Allitinib, there are limited predictive markers for their response. Understanding molecular aberrations in HNSCC could facilitate the identification of new strategies for patient clinical and biological classification, offering novel therapeutic avenues. METHODS: We assessed CCNA1, DCC, MGMT, CDKN2A/p16, and DAPK methylation status in HNSCC cell lines and their association with anti-EGFR treatment response. RESULTS: MGMT methylation status displayed high sensitivity and specificity in distinguishing sensitive and resistant HNSCC cell lines to Afatinib (AUC = 0.955) and Allitinib (AUC = 0.935). Moreover, DAPK methylation status predicted response to Allitinib with high accuracy (AUC = 0.852), indicating their putative predictive biomarker roles. CONCLUSION: These findings hold promise for the development of more personalized and effective treatment approaches for HNSCC patients.

miR-99a-5p as a biomarker for lymph node metastasis prediction in oral squamous cell carcinoma patients.

BACKGROUND: Metastatic lymph node involvement influences therapy decisions and serves as a prognostic indicator in oral squamous cell carcinoma (OSCC). However, many early-stage patients with clinically negative lymph nodes exhibit no metastasis upon surgical staging. This study aimed to identify differentially expressed miRNAs capable of distinguishing pathologically positive (pN+) from negative (pN0) nodes in OSCC patients without clinical evidence of lymph node metastases (cN0). METHODS: Expression levels of 798 miRNAs were assessed in tumor samples from 10 pN+ and 10 pN0 patients using the Nanostring nCounter platform. Validation was performed in an independent cohort of 15 pN+ and 24 pN0 patients through RT-qPCR. RESULTS: Eight miRNAs exhibited differential expression between pN0 and pN+ patients. Notably, hsa-miR-99a-5p demonstrated high sensitivity and specificity in predicting patients at higher risk of positive lymph nodes. CONCLUSIONS: These findings highlight hsa-miR-99a-5p as a potential biomarker for detecting lymph node metastasis in primary OSCC tumors.

XPERT® breast cancer STRAT4 as an alternative method of identifying breast cancer phenotype in Cape Verde (preliminary results).

Introduction: Breast cancer (BC) is a public health problem in developing countries, including Cape Verde. Immunohistochemistry (IHC) is the gold standard technique used for BC phenotypic characterisation to support efficient therapeutic decisions. However, IHC is a demanding technique that requires knowledge, trained technicians, expensive antibodies and reagents, controls, and results validation. The low number of cases in Cape Verde increases the risk of expiring the validity of the antibodies, and manual procedures often jeopardise the quality of the results. Thus, IHC is limited in Cape Verde, and an alternative technically easy solution is needed. A point-of-care messenger RNA (mRNA) STRAT4 BC assay to assess estrogen (ER), progesterone (PR), hormone growth factor 2 receptor (HER2), and Ki67, using the GeneXpert platform, has been recently validated on tissues from internationally accredited laboratories, showing excellent concordance with IHC results.To assess whether this technology can be implemented in Cape Verde to guide BC treatment we decided to study the level of agreement between the findings yielded by BC STRAT4 and the results are the same cases obtained by IHC. Methods: Formalin-fixed and paraffin-embedded (FFPE) tissue samples from 29 Cabo Verdean BC patients diagnosed in Agostinho Neto University Hospital were analysed by applying IHC and BC STRAT4 assay. The time between sample collection and pre-analytic procedures is unknown. All the samples were pre-processed in Cabo Verde (fixed in formalin and embedded in paraffin). IHC studies were performed in referenced laboratories in Portugal. STRAT4 and IHC result concordance was assessed by calculating the percentage of results agreement and Cohen's Kappa (K) statistics. Results: STRAT4 assay failed in 2 out of the 29 analysed samples. Of the 27 successfully analysed samples, STRAT4/IHC results for ER, PR, HER2, and Ki67 were concordant in 25, 24, 25, and 18 cases, respectively. Ki67 was indeterminate in three cases, and PR was indeterminate once.The percentage of agreement between STRAT4 and IHC results for ER, PR, HER2, and Ki67 was 92.59%, 92.31%, 92.59% and 81.82%, respectively. The Cohen's K statistic coefficients for each biomarker were 0.809, 0.845, 0.757 and 0.506, respectively. Conclusions: According to our preliminary results, a point-of-care mRNA STRAT4 BC assay may be an alternative in laboratories unable to provide quality and/or cost-efficient IHC services. However, more data and improvement on sample pre-analytic processes are required to implement this BC STRAT4 Assay in Cape Verde.

Plasma metabolomics of oral squamous cell carcinomas based on NMR and MS approaches provides biomarker identification and survival prediction.

Metabolomics has proven to be an important omics approach to understand the molecular pathways underlying the tumour phenotype and to identify new clinically useful markers. The literature on cancer has illustrated the potential of this approach as a diagnostic and prognostic tool. The present study aimed to analyse the plasma metabolic profile of patients with oral squamous cell carcinoma (OSCC) and controls and to compare patients with metastatic and primary tumours at different stages and subsites using nuclear magnetic resonance and mass spectrometry. To our knowledge, this is the only report that compared patients at different stages and subsites and replicates collected in diverse institutions at different times using these methodologies. Our results showed a plasma metabolic OSCC profile suggestive of abnormal ketogenesis, lipogenesis and energy metabolism, which is already present in early phases but is more evident in advanced stages of the disease. Reduced levels of several metabolites were also associated with an unfavorable prognosis. The observed metabolomic alterations may contribute to inflammation, immune response inhibition and tumour growth, and may be explained by four nonexclusive views-differential synthesis, uptake, release, and degradation of metabolites. The interpretation that assimilates these views is the cross talk between neoplastic and normal cells in the tumour microenvironment or in more distant anatomical sites, connected by biofluids, signalling molecules and vesicles. Additional population samples to evaluate the details of these molecular processes may lead to the discovery of new biomarkers and novel strategies for OSCC prevention and treatment.

Cumulative Coffee Consumption as a Protective Factor for Head and Neck Cancer in Brazil.

There is still no consensus in the literature regarding the role of coffee in head and neck cancer. Thus, we sought to analyze the cumulative consumption of coffee as a protective factor in the genesis of head and neck cancer in Brazil, one of the main coffee producing countries, from January 2011 to February 2017. We carried out a case-control study in 5 referral centers for head and neck cancer with 839 cases and 842 non-cancer hospital controls matched by sex, data collection center and age group. The results of logistic regression analysis showed that the cumulative consumption of >2 cups of coffee per day is an important protective factor (OR: 0.73, 95% CI: 0.5-0.9) against head and neck cancer. Smoking increased the risk by 22 times (OR: 22.19; 95% CI: 13.7-35.8) in individuals who smoke more than 50 packs per year, and the habit of ingesting more than 155 ml of alcohol per day represented approximately twice as high risk (OR: 2.20; 95% CI: 1.4-3.4). In summary, this study suggests that coffee consumption is associated with a lower chance of head and neck cancer.

Clinical predictors of malignant transformation and recurrence in oral potentially malignant disorders: A systematic review and meta-analysis.

OBJECTIVE: We performed a systematic review dedicated to pooling evidence for the associations of clinical features with malignant transformation (MT) and recurrence of 3 oral potentially malignant disorders (OPMDs) (actinic cheilitis [AC], oral leukoplakia [OL], and proliferative verrucous leukoplakia [PVL]). STUDY DESIGN: We selected studies that included clinical features and risk factors (age, sex, site, size, appearance, alcohol intake, tobacco use, and sun exposure) of OL, PVL, and AC associated with recurrence and/or MT. RESULTS: Based on the meta-analysis results, non-homogeneous OL appears to have a 4.53 times higher chance of recurrence after treatment. We also found 6.52 higher chances of MT of non-homogeneous OL. Another clinical feature related to higher MT chances is the location (floor of the mouth and tongue has 4.48 higher chances) and the size (OL with >200 mm2 in size has 4.10 higher chances of MT). Regarding habits, nonsmoking patients with OL have a 3.20 higher chance of MT. The only clinical feature related to higher chances of MT in patients with PVL was sex (females have a 2.50 higher chance of MT). CONCLUSIONS: Our study showed that some clinical features may indicate greater chances of recurrence after treatment and MT of OPMD.

Adherence to a shoulder dysfunction physical therapy protocol after neck dissection with accessory nerve preservation in head-and-neck cancer patients: An uncontrolled clinical trial.

Objective: Accessory nerve (AN) manipulation or resection during neck dissection (ND) generates accessory nerve shoulder dysfunction (ANSD). The aim of the present study was to assess adherence to a supervised physiotherapy protocol and subsequent changes in the functionality scores of patients with ASND with accessory nerve (AN) preservation. Methods: This study consisted of an uncontrolled clinical trial was carried out at the Department of Head and Neck Surgery and Otorhinolaryngology at the A.C. Camargo Cancer Center, comprising progressive isotonic and isometric strengthening of scapular stabilizer muscles. In patients with head-and-neck cancer underwent ND with AN preservation and patients with ANSD. Shoulder range of motion (ROM), middle trapezius, lower trapezius, rhomboid and anterior serratus muscle strength, pain, and quality of life (QoL) were measured in the pre-operative and 1st and 3rd post-operative months. There were included patients over 18 years old, with head-and-neck cancer who underwent ND with AN preservation and patients with ANSD. Results: A total of 55 patients were evaluated, with a mean age of 53 (±13.23). Significant improvement in the functionality scores of almost all variables between pre- and post- physiotherapy was observed. Most patients (70.9%) adhered and completed the protocol, obtaining significantly greater ROM abduction (P = 0.009) and lower trapezius strength (P = 0.011) than partially performing patients. Conclusion: When performed completely, the proposed physiotherapy protocol can minimize loss in muscle movements and strength, especially limited after ND. The results indicate that the proposed protocol is safe and has the potential to reduce ANSD.

Cutaneous and acral melanoma cross-OMICs reveals prognostic cancer drivers associated with pathobiology and ultraviolet exposure.

Ultraviolet radiation (UV) is causally linked to cutaneous melanoma, yet the underlying epigenetic mechanisms, known as molecular sensors of exposure, have not been characterized in clinical biospecimens. Here, we integrate clinical, epigenome (DNA methylome), genome and transcriptome profiling of 112 cutaneous melanoma from two multi-ethnic cohorts. We identify UV-related alterations in regulatory regions and immunological pathways, with multi-OMICs cancer driver potential affecting patient survival. TAPBP, the top gene, is critically involved in immune function and encompasses several UV-altered methylation sites that were validated by targeted sequencing, providing cost-effective opportunities for clinical application. The DNA methylome also reveals non UV-related aberrations underlying pathological differences between the cutaneous and 17 acral melanomas. Unsupervised epigenomic mapping demonstrated that non UV-mutant cutaneous melanoma more closely resembles acral rather than UV-exposed cutaneous melanoma, with the latter showing better patient prognosis than the other two forms. These gene-environment interactions reveal translationally impactful mechanisms in melanomagenesis.

Cost-Effectiveness of BRCA 1/2 Genetic Test and Preventive Strategies: Using Real-World Data From an Upper-Middle Income Country.

Although BRCA1/2 genetic testing in developed countries is part of the reality for high-risk patients for hereditary breast and ovarian cancer (HBOC), the same is not true for upper-middle-income countries. For that reason, this study aimed to evaluate whether the BRCA1/2 genetic test and preventive strategies for women at high risk for HBOC are cost-effective compared to not performing these strategies in an upper-middle-income country. Adopting a payer perspective, a Markov model with a time horizon of 70 years was built to delineate the health states for a cohort of healthy women aged 30 years that fulfilled the BRCA1/2 testing criteria according to the guidelines. Transition probabilities were calculated based on real-world data of women tested for BRCA1/2 germline mutations in a cancer reference hospital from 2011 to 2020. We analyzed 275 BRCA mutated index cases and 356 BRCA mutation carriers that were first- or second-degree relatives of the patients. Costs were based on the Brazilian public health system reimbursement values. Health state utilities were retrieved from literature. The BRCA1/2 genetic test and preventive strategies result in more quality-adjusted life years (QALYs) and costs with an incremental cost-effectiveness ratio of R$ 11,900.31 (U$ 5,504.31)/QALY. This result can represent a strong argument in favor of implementing genetic testing strategies for high-risk women even in countries with upper-middle income, considering not only the cancer prevention possibilities associated with the genetic testing but also its cost-effectiveness to the health system. These strategies are cost-effective, considering a willingness-to-pay threshold of R$ 25,000 (U$ 11,563.37)/QALY, indicating that the government should consider offering them for women at high risk for HBOC. The results were robust in deterministic and probabilistic sensitivity analyses.

Sentinel lymph node biopsy for early squamous cell carcinoma of the lip and oral cavity: Real-world experience in Brazil.

BACKGROUND: This study aimed to evaluate the accuracy and oncological results of sentinel lymph node biopsy in patients with early lip and oral cavity squamous cell carcinoma (SCC) in a real-world scenario. METHODS: Retrospective study including seven Brazilian centers. RESULTS: Four-hundred and seven cN0 patients were accrued for 20 years. The rate of occult metastasis was 23.1% and 22 patients (5.4%) had regional failure. We found, for 5 years of follow-up, 85.3% of regional recurrence-free survival; 77.1% of disease-free survival; 73.7% of overall survival; and 86.7% of disease-specific survival. The rate of false-negative cases was 5.4%. CONCLUSION: In a real-world scenario, sentinel lymph node biopsy for patients with SCC of the lip and oral cavity proved feasible in different settings and to be oncologically safe, with similar rates of occult lymph node metastasis and false-negative cases, when compared to elective neck dissection, and with similar long-term survival to that reported historically.

Progressive Increase Trend in HPV-Related Oropharyngeal Squamous Cell Carcinoma in Brazil

Abstract Introduction The prevalence of oropharyngeal squamous cell carcinoma (OSCC) related to Human Papillomavirus (HPV) is rising in the whole world. Objective To access the prevalence and temporal trend of HPV infection in oropharyngeal cancer by analyzing the expression of the p16 protein. Methods We conducted a transversal study in a Brazilian reference oncology center. The sample consisted of 254 patients with OSCC. The analyzed period was from 2013 to 2017. All patients underwent p16 immunohistochemistry analysis. Results The overall prevalence of HPV-related OSCC was of 31.9%. During the analyzed period, we observed a trend of increasing rates of OSCC that marked positive for p16 immunohistochemistry. The annual prevalence of p16-positive cases was of 20.6% in 2013, 23.9% in 2014, 33.3% in 2015, 38.3% in 2016, and 34.2% in 2017. Most of the patients were stage III and IV (84%). Female patients (odds ratio [OR] = 2.43; 95% confidence interval [CI]: 1.003-5.888; p = 0.049) and younger patients (OR = 2.919; 95%CI: 1.682-5.067; p < 0.005) were associated with a higher risk of HPV-related OSCC. Tobacco consumption had a proportional lower risk of HPV-related OSCC (OR = 0.152; 95%CI: 0063-0.366; p < 0.005). Conclusion We observed an increasing prevalence of HPV-related OSCC in a specialized cancer hospital in Brazil.

Progressive Increase Trend in HPV-Related Oropharyngeal Squamous Cell Carcinoma in Brazil.

Introduction The prevalence of oropharyngeal squamous cell carcinoma (OSCC) related to Human Papillomavirus (HPV) is rising in the whole world. Objective To access the prevalence and temporal trend of HPV infection in oropharyngeal cancer by analyzing the expression of the p16 protein. Methods We conducted a transversal study in a Brazilian reference oncology center. The sample consisted of 254 patients with OSCC. The analyzed period was from 2013 to 2017. All patients underwent p16 immunohistochemistry analysis. Results The overall prevalence of HPV-related OSCC was of 31.9%. During the analyzed period, we observed a trend of increasing rates of OSCC that marked positive for p16 immunohistochemistry. The annual prevalence of p16-positive cases was of 20.6% in 2013, 23.9% in 2014, 33.3% in 2015, 38.3% in 2016, and 34.2% in 2017. Most of the patients were stage III and IV (84%). Female patients (odds ratio [OR] = 2.43; 95% confidence interval [CI]: 1.003-5.888; p = 0.049) and younger patients (OR = 2.919; 95%CI: 1.682-5.067; p < 0.005) were associated with a higher risk of HPV-related OSCC. Tobacco consumption had a proportional lower risk of HPV-related OSCC (OR = 0.152; 95%CI: 0063-0.366; p < 0.005). Conclusion We observed an increasing prevalence of HPV-related OSCC in a specialized cancer hospital in Brazil.

One-carbon metabolism and global DNA methylation in mothers of individuals with Down syndrome.

Down syndrome (DS) is the most common chromosomal disorder, resulting from the failure of normal chromosome 21 segregation. Studies have suggested that impairments within the one-carbon metabolic pathway can be of relevance for the global genome instability observed in mothers of individuals with DS. Based on the association between global DNA hypomethylation, genome instability, and impairments within the one-carbon metabolic pathway, the present study aimed to identify possible predictors, within the one-carbon metabolism, of global DNA methylation, measured by methylation patterns of LINE-1 and Alu repetitive sequences, in mothers of individuals with DS and mothers of individuals without the syndrome. In addition, we investigated one-carbon genetic polymorphisms and metabolites as maternal predisposing factors for the occurrence of trisomy 21 in children. Eighty-three samples of mothers of children with DS with karyotypically confirmed free trisomy 21 (case group) and 84 of mothers who had at least one child without DS or any other aneuploidy were included in the study. Pyrosequencing assays were performed to access global methylation. The results showed that group affiliation (case or control), betaine-homocysteine methyltransferase (BHMT) G742A and transcobalamin 2 (TCN2) C776G polymorphisms, and folate concentration were identified as predictors of global Alu DNA methylation values. In addition, thymidylate synthase (TYMS) 28-bp repeats 2R/3R or 3R/3R genotypes are independent maternal predisposing factors for having a child with DS. This study adds evidence that supports the association of impairments in the one-carbon metabolism, global DNA methylation, and the possibility of having a child with DS.

Evaluation of acetylation and methylation in oral rinse of patients with head and neck cancer history exposed to valproic acid.

Evaluate the biological action of valproic acid in the acetylation of histones and in the methylation of tumor suppressor genes via oral rinse in patients with a previous history of head and neck squamous cell carcinoma (HNSCC). Forty-two active or former smokers were included in this randomized, double-blind, placebo-controlled trial. Oral rinse samples were collected prior to treatment with valproic acid or placebo and after 90 days of treatment. The methylation status of five tumor suppressor genes and histone acetylation were evaluated by pyrosequencing and ELISA techniques, respectively. Differences between the 90-day and baseline oral rinse acetylation and methylation results were analyzed by comparing groups. Thirty-four patients were considered for analysis. The mean percentage adherence in the valproic and placebo groups was 93.4 and 93.0, respectively (p = 0.718). There was no statistically significant difference between groups when comparing the medians of the histone acetylation ratio and the methylation ratio for most of the studied genes. A significant reduction in the DCC methylation pattern was observed in the valproic group (p = 0.023). The use of valproic acid was safe and accompanied by good therapeutic adherence. DCC methylation was lower in the valproic acid group than in the placebo group.

DNA Methylation Markers from Negative Surgical Margins Can Predict Recurrence of Oral Squamous Cell Carcinoma.

The identification of molecular markers in negative surgical margins of oral squamous cell carcinoma (OSCC) might help in identifying residual molecular aberrations, and potentially improve the prediction of prognosis. We performed an Infinium MethylationEPIC BeadChip array on 32 negative surgical margins stratified based on the status of tumor recurrence in order to identify recurrence-specific aberrant DNA methylation (DNAme) markers. We identified 2512 recurrence-associated Differentially Methylated Positions (DMPs) and 392 Differentially Methylated Regions (DMRs) which were enriched in cell signaling and cancer-related pathways. A set of 14-CpG markers was able to discriminate recurrent and non-recurrent cases with high specificity and sensitivity rates (AUC 0.98, p = 3 × 10-6; CI: 0.95-1). A risk score based on the 14-CpG marker panel was applied, with cases classified within higher risk scores exhibiting poorer survival. The results were replicated using tumor-adjacent normal HNSCC samples from The Cancer Genome Atlas (TCGA). We identified residual DNAme aberrations in the negative surgical margins of OSCC patients, which could be informative for patient management by improving therapeutic intervention. This study proposes a novel DNAme-based 14-CpG marker panel as a promising predictor for tumor recurrence, which might contribute to improved decision-making for the personalized treatment of OSCC cases.

The hidden curve behind COVID-19 outbreak: the impact of delay in treatment initiation in cancer patients and how to mitigate the additional risk of dying-the head and neck cancer model.

PURPOSE: The rapid spread of the SARS-CoV-2 pandemic around the world caused most healthcare services to turn substantial attention to treatment of these patients and also to alter the structure of healthcare systems to address an infectious disease. As a result, many cancer patients had their treatment deferred during the pandemic, increasing the time-to-treatment initiation, the number of untreated patients (which will alter the dynamics of healthcare delivery in the post-pandemic era) and increasing their risk of death. Hence, we analyzed the impact on global cancer mortality considering the decline in oncology care during the COVID-19 outbreak using head and neck cancer, a known time-dependent disease, as a model. METHODS: An online practical tool capable of predicting the risk of cancer patients dying due to the COVID-19 outbreak and also useful for mitigation strategies after the peak of the pandemic has been developed, based on a mathematical model. The scenarios were estimated by information of 15 oncological services worldwide, given a perspective from the five continents and also some simulations were conducted at world demographic data. RESULTS: The model demonstrates that the more that cancer care was maintained during the outbreak and also the more it is increased during the mitigation period, the shorter will be the recovery, lessening the additional risk of dying due to time-to-treatment initiation. CONCLUSIONS: This impact of COVID-19 pandemic on cancer patients is inevitable, but it is possible to minimize it with an effort measured by the proposed model.

The effect of bone marrow-derived stem cells associated with platelet-rich plasma on the osseointegration of immediately placed implants.

BACKGROUND: Stem cells associated with growth factors have been shown to improve bone healing and the osseointegration of dental implants. A Brazilian miniature pig model was used to evaluate the effect of autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) associated with platelet-rich plasma (PRP) on the osseointegration of immediately placed dental implants. MATERIAL AND METHODS: A total of four male adult miniature pigs were used in this study. BM-MSCs from each pig were isolated from the iliac crest and expanded in vitro. The undifferentiated BM-MSCs were mixed with autologous PRP and implanted in the post-extraction sockets at the experimental sites before implant placement (10 x 106 cells/ socket). The control sites did not receive either BM-MSC or PRP. Each animal received four implants in the control side and 04 on the experimental side, totalizing 32 implants. The specimens were analyzed radiographically and histomorphometrically to determine the implant loss rate (ILR), the bone-implant contact (BIC), and bone density within the threads (BDWT). RESULTS: The ILR, the BIC, and the BDWT for the control and experimental sites were respectively 25.0% and 18.7% (p=0.686); 39.0% and 27.7% (p=0.110); 46.8% and 36.5% (p=0.247). CONCLUSIONS: The use of BM-MSCs + PRP in conjunction with immediately placed implants showed a lower ILR but there was no significant effect on the osseointegration of the dental implants. More preclinical studies, in large animal models, are needed to establish whether BM-MSCs associated with PRP could be used for the enhancement of the osseointegration of dental implants. Key words:Osseointegration, bone marrow-derived mesenchymal stem cells, platelet-rich plasma, dental implants, minipigs.

Human Papillomavirus DNA Detection by Droplet Digital PCR in Formalin-Fixed Paraffin-Embedded Tumor Tissue from Oropharyngeal Squamous Cell Carcinoma Patients.

INTRODUCTION: High-risk human papillomavirus infection impacts staging and prognosis of oropharyngeal squamous cell carcinomas (OPSCCs). Determination of HPV status in tumor tissue by p16-immunohistochemistry (p16-IHC) can be challenging; therefore, complementary methodologies could be useful in a clinical setting. OBJECTIVE: To test for accuracy and clinical relevance of HPV-DNA detection in formalin-fixed and paraffin-embedded (FFPE) tumor samples by droplet digital PCR (ddPCR). MATERIALS AND METHODS: Fifty OPSCCs were tested for p16-IHC status followed by HPV-16/18 DNA detection/quantification in FFPE-recovered DNA using ddPCR. Accuracy for HPV status determination and association with patient information were also evaluated. RESULTS: 32.0% (16/50) of the cases were p16-IHC positive (p16 +), 42.0% (21/50) had detectable levels of HPV-16 DNA, and none were positive for HPV-18 DNA. A higher median viral load of HPV-16 DNA was observed in p16 + cases (p < 0.0001). Concordance between p16-IHC and HPV-16 DNA ranged from 78.0 to 86.0% and accuracy rates were between 78.0 and 86.0%. P16-IHC and HPV-16 DNA detection was associated with gender, smoking status, and tumor subsite, while only HPV-16 DNA was associated with cT stage. The combination of HPV positivity by p16-IHC and ddPCR showed higher overall survival rates in comparison with p16 + /HPV-DNA- and p16 - /HPV-DNA- results. CONCLUSIONS: Type-specific HPV-DNA detection by ddPCR is highly specific but moderately sensitive for the determination of HPV status and showed clinical relevance, mainly when associated with p16-IHC status. Results highlight the importance of performing HPV-DNA testing in combination with p16-IHC for proper identification of HPV-associated OPSCC and to improve clinical management of OPSCC patients.

Electrochemical and optical detection and machine learning applied to images of genosensors for diagnosis of prostate cancer with the biomarker PCA3.

The development of simple detection methods aimed at widespread screening and testing is crucial for many infections and diseases, including prostate cancer where early diagnosis increases the chances of cure considerably. In this paper, we report on genosensors with different detection principles for a prostate cancer specific DNA sequence (PCA3). The genosensors were made with carbon printed electrodes or quartz coated with layer-by-layer (LbL) films containing gold nanoparticles and chondroitin sulfate and a layer of a complementary DNA sequence (PCA3 probe). The highest sensitivity was reached with electrochemical impedance spectroscopy with the detection limit of 83 pM in solutions of PCA3, while the limits of detection were 2000 pM and 900 pM for cyclic voltammetry and UV-vis spectroscopy, respectively. That detection could be performed with an optical method is encouraging, as one may envisage extending it to colorimetric tests. Since the morphology of sensing units is known to be affected in detection experiments, we applied machine learning algorithms to classify scanning electron microscopy images of the genosensors and managed to distinguish those exposed to PCA3-containing solutions from control measurements with an accuracy of 99.9%. The performance in distinguishing each individual PCA3 concentration in a multiclass task was lower, with an accuracy of 88.3%, which means that further developments in image analysis are required for this innovative approach.