Reliable biomarkers for oral cancer remain scarce and routine tests for the detection of pre-cancerous lesions are not routine in the clinical setting. This study addresses a current unmet need for more sensitive and quantitative tools for the management of oral cancer. Whole saliva was used to identify and characterise the nature of glycans present in saliva and determine their potential as oral cancer biomarkers. Proteins obtained from whole saliva were subjected to PNGase F enzymatic digestion. The resulting N-glycans were analysed with weak anion exchange chromatography, exoglycosidase digestions coupled to ultra-high performance liquid chromatography (UHPLC) and/or mass spectrometry (MS). To determine N-glycan changes, 23 individuals with or without cancerous oral lesions were analysed using HILIC-UPLC and peak based area relative quantitation was performed. An abundant and complex salivary N-glycomic profile was identified. The main structures present in saliva were neutral oligosaccharides consisting of high mannose, hybrid and complex structures, followed by smaller fractions of mono and di-sialylated structures. To determine if differential N-glycosylation patterns distinguish between oral cancer and control groups, Mann-Whitney testing and Principle Component Analysis (PCA) were used. 11 peaks were shown to be statistically significant (p ≤ 0.05) while PCA analysis showed segregation of the two groups based on their glycan profile. N-glycosylation changes are active in the oral carcinogenic process, and may serve as biomarkers for early detection to reduce morbidity and mortality. Identifying which N-glycans contribute most in the carcinogenic process, may lead to their use in the detection, prognosis and treatment of OC.

Although immune checkpoint inhibitors (ICI) have revolutionized cancer management, patient response can be heterogeneous, and the development of ICI resistance is increasingly reported. Novel treatment strategies are necessary not only to expand the use of ICI to previously unresponsive tumor types but also to overcome resistance. Targeted radionuclide therapy may synergize well with ICIs since it can promote a pro-inflammatory tumor microenvironment. We investigated the use of a granzyme B targeted peptide (GZP) as a cancer theranostic agent, radiolabeled with ⁶⁸Ga (⁶⁸Ga-GZP) as a PET imaging agent and radiolabeled with ⁹⁰Y (⁹⁰Y-GZP) as a targeted radionuclide therapy agent for combinational therapy with ICI in murine models of colon cancer. Our results demonstrate that GZP increasingly accumulates in tumor tissue after ICI and that the combination of ICI with ⁹⁰Y-GZP promotes a dose-dependent response, achieving curative response in some settings and increased overall survival.

Background: Since the serendipitous discovery of bovine α-lactalbumin made lethal to tumour cells (BAMLET)/human α-lactalbumin made lethal to tumour cells there has been an increased interest in the ability of the two components, oleic acid and α-lactalbumin, to form anti-cancer complexes. Here we have investigated the in-vitro efficacy of the BAMLET complex in killing oral cancer (OC) cells, determined the active component of the complex and investigated possible biological mechanisms. Materials and methods: Two OC cell lines (±p53 mutation) and one dysplastic cell line were used as a model of progressive oral carcinogenesis. We performed cell viability assays with increasing BAMLET concentrations to determine the cytotoxic potential of the complex. We further analysed the individual components to determine their respective cytotoxicities. siRNA knockdown of p53 was used to determine its functional role in mediating sensitivity to BAMLET. Cell death mechanisms were investigated by flow cytometry, confocal microscopy and the lactate dehydrogenase assay. Results: Our results show that BAMLET is cytotoxic to the OC and dysplastic cell lines in a time and dose-dependent manner. The cytotoxic component was found to be oleic acid, which, can induce cytotoxicity even when not in complex. Our results indicate that the mechanism of cytotoxicity occurs through multiple simultaneous events including cell cycle arrest, autophagy like processes with a minor involvement of necrosis. Conclusion: Deciphering the mechanism of cytotoxicity will aid treatment modalities for OC. This study highlights the potential of BAMLET as a novel therapeutic strategy in oral dysplastic and cancerous cells.