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Oral cancer (OC) is the most common form of head and neck cancer. Despite the high incidence and unfavourable patient outcomes, currently, there are no biomarkers for the early detection of OC. This study aims to discover, develop, and validate a novel saliva-based microRNA signature for early diagnosis and prediction of OC risk in oral potentially malignant disorders (OPMD). The Cancer Genome Atlas (TCGA) miRNA sequencing data and small RNA sequencing data of saliva samples were used to discover differentially expressed miRNAs. Identified miRNAs were validated in saliva samples of OC (n = 50), OPMD (n = 52), and controls (n = 60) using quantitative real-time PCR. Eight differentially expressed miRNAs (miR-7-5p, miR-10b-5p, miR-182-5p, miR-215-5p, miR-431-5p, miR-486-3p, miR-3614-5p, and miR-4707-3p) were identified in the discovery phase and were validated. The efficiency of our eight-miRNA signature to discriminate OC and controls was: area under curve (AUC): 0.954, sensitivity: 86%, specificity: 90%, positive predictive value (PPV): 87.8% and negative predictive value (NPV): 88.5% whereas between OC and OPMD was: AUC: 0.911, sensitivity: 90%, specificity: 82.7%, PPV: 74.2% and NPV: 89.6%. We have developed a risk probability score to predict the presence or risk of OC in OPMD patients. We established a salivary miRNA signature that can aid in diagnosing and predicting OC, revolutionising the management of patients with OPMD. Together, our results shed new light on the management of OC by salivary miRNAs to the clinical utility of using miRNAs derived from saliva samples., (© 2024. The Author(s).)

Circulating tumor cells (CTCs) carry a wealth of information on primary and metastatic tumors critical for precise cancer detection, monitoring, and treatment. Numerous microfluidic platforms have been developed in the past few years to capture these rare cells in patient bloodstream for deciphering the critical information needed. However, the practical need for a high-quality method of CTC isolation remains to be met. Herein, we demonstrate a novel multi-flow microfluidic device that is able to sensitively provide high purity (>87%) of separation outcome without labeling. Our device is constructed and configured based on the phenomenal effect of size-dependent inertial migration. The recovery rate of >93% has been achieved using spiked cancer cells at clinically relevant concentrations (10 cells per 5 mL and above). We have also successfully detected CTCs from 6 out of 8 non-small-cell-lung-cancer (NSCLC) patients, while none for 5 healthy control subjects. With these results, we envision our approach is a promising alternative for reliable CTC capture, and thus for facilitating the progress of extracting information from CTCs to personalize treatment strategies for solid tumor patients., Competing Interests: The authors declare that they have no conflict of interest.

Distant metastasis (DM) from head and neck cancers (HNC) portends a poor patient prognosis. Despite its important biological role, little is known about the cells which seed these DM. Circulating tumour cells (CTCs) represent a transient cancer cell population, which circulate in HNC patients' peripheral blood and seed at distant sites. Capture and analysis of CTCs offers insights into tumour metastasis and can facilitate treatment strategies. Whilst the data on singular CTCs have shown clinical significance, the role of CTC clusters in metastasis remains limited. In this pilot study, we assessed 60 treatment naïve HNC patients for CTCs with disease ranging from early to advanced stages, for CTC clusters utilizing spiral CTC enrichment technology. Single CTCs were isolated in 18/60-30% (Ranging from Stage I-IV), CTC clusters in 15/60-25% (exclusively Stage IV) with 3/15-20% of CTC clusters also containing leukocytes. The presence of CTC clusters associated with the development of distant metastatic disease(P = 0.0313). This study demonstrates that CTC clusters are found in locally advanced patients, and this may be an important prognostic marker. In vivo and in vitro studies are warranted to determine the role of these CTC clusters, in particular, whether leukocyte involvement in CTC clusters has clinical relevance.

Saliva has attracted attention as a diagnostic fluid due to the association of oral microbiota with systemic diseases. However, the lack of standardised methods for saliva collection has led to the slow uptake of saliva in microbiome research. The aim of this study was to systematically evaluate the potential effects on salivary microbiome profiles using different methods of saliva collection, storage and gDNA extraction. Three types of saliva fractions were collected from healthy individuals with or without the gDNA stabilising buffer. Subsequently, three types of gDNA extraction methods were evaluated to determine the gDNA extraction efficiencies from saliva samples. The purity of total bacterial gDNA was evaluated using the ratio of human β-globin to bacterial 16S rRNA PCR while 16S rRNA gene amplicon sequencing was carried out to identify the bacterial profiles present in these samples. The quantity and quality of extracted gDNA were similar among all three gDNA extraction methods and there were no statistically significant differences in the bacterial profiles among different saliva fractions at the genus-level of taxonomic classification. In conclusion, saliva sampling, processing and gDNA preparation do not have major influence on microbiome profiles.

Whilst locoregional control of head and neck cancers (HNCs) has improved over the last four decades, long-term survival has remained largely unchanged. A possible reason for this is that the rate of distant metastasis has not changed. Such disseminated disease is reflected in measurable levels of cancer cells in the blood of HNC patients, referred to as circulating tumour cells (CTCs). Numerous marker-independent techniques have been developed for CTC isolation and detection. Recently, microfluidics-based platforms have come to the fore to avoid molecular bias. In this pilot, proof of concept study, we evaluated the use of the spiral microfluidic chip for CTC enrichment and subsequent detection in HNC patients. CTCs were detected in 13/24 (54%) HNC patients, representing both early to late stages of disease. Importantly, in 7/13 CTC-positive patients, CTC clusters were observed. This is the first study to use spiral microfluidics technology for CTC enrichment in HNC.

Objective: The effects of free fatty acids (FFA), leptin, tumour necrosis factor (TNF) alpha and body fat distribution on in vivo oxidation of a glucose load were studied in two South African ethnic groups., Design and Measurements: Anthropometric and various metabolic indices were measured at fasting and during a 7 h oral glucose tolerance test (OGTT). Body composition was measured using bioelectrical impedance analysis and subcutaneous and visceral fat mass was assessed using a five- and two-level CT-scan respectively. Glucose oxidation was evaluated by measuring the ratio of (13)CO(2) to (12)CO(2) in breath following ingestion of 1-(13)C-labelled glucose., Subjects: Ten lean black women (LBW), ten obese black women (OBW), nine lean white women (LWW) and nine obese white women (OWW) were investigated after an overnight fast., Results: Visceral fat levels were significantly higher (P<0.01) in obese white than black women, despite similar body mass indexes (BMIs). There were no ethnic differences in glucose oxidation however; in the lean subjects of both ethnic groups the area under the curve (AUC) was higher than in obese subjects (P<0.05 for both) and was found to correlate negatively with weight (r=-0.69, P<0.01) after correcting for age. Basal TNF alpha concentrations were similar in all groups. Percentage suppression of FFAs at 30 min of the OGTT was 24+/-12% in OWW and -38+/-23% (P<0.05) in OBW, ie the 30 min FFA level was higher than the fasting level in the latter group. AUC for FFAs during the late postprandial period (120--420 min) was significantly higher in OWW than OBW (P<0.01) and LWW (P<0.01) and correlated positively with visceral fat mass independent of age (r=0.78, P<0.05) in the OWW only. Leptin levels were higher (P<0.01) both at fasting and during the course of the OGTT in obese women from both ethnic groups compared to the lean women., Conclusions: Glucose oxidation is reduced in obese subjects of both ethnic groups; inter- and intra-ethnic differences were observed in visceral fat mass and FFA production and it is possible that such differences may play a role in the differing prevalences of obesity-related disorders that have been reported in these two populations.