Drug repurposing is an unconventional drug discovery approach to explore new therapeutic benefits of existing, shelved and the drugs in clinical trials. This approach is currently emerging to overcome the bottleneck constraints faced during traditional drug discovery in grounds of financial support, timeline and resources. In this direction, several efforts were made for the construction of stratagems based on bioinformatics and computational tools to intensify the repurposing process off-late. Further, advanced research has succeeded in widening its boundaries in identification of gene targets and subsequent molecular interactions of the drugs depending on available omics data. Currently, the advent of data repositories like Connectivity Map (CMap), Library Integrated Network based Cellular Signatures (LINCS), Genome Wide Association Studies (GWAS), Side Effect Resource (SIDER), and Directionality Map (DMAP) has bestowed great oppurtunity to the researchers in improving their drug repurposing research exponentially. On the otherhand, in silico approaches like pharmacophore modelling and docking techniques circumvent the routine tedious in vitro and in vivo techniques involved in former screening phases of the drugs and disease specific targets. This review elaborates on currently designed contemporary tools, databases and strategies with relevant case studies.

Oral cancer is one of the 19most rapidly progressing cancers associated with significant mortality, owing to its extreme degree of invasiveness and aggressive inclination. The early occurrences of this cancer can be clinically deceiving leading to a poor overall survival rate. The primary concerns from a clinical perspective include delayed diagnosis, rapid disease progression, resistance to various chemotherapeutic regimens, and aggressive metastasis, which collectively pose a substantial threat to prognosis. Conventional clinical practices observed since antiquity no longer offer the best possible options to circumvent these roadblocks. The world of current cancer research has been revolutionized with the advent of state-of-the-art technology-driven strategies that offer a ray of hope in confronting said challenges by highlighting the crucial underlying molecular mechanisms and drivers. In recent years, bioinformatics and Machine Learning (ML) techniques have enhanced the possibility of early detection, evaluation of prognosis, and individualization of therapy. This review elaborates on the application of the aforesaid techniques in unraveling potential hints from omics big data to address the complexities existing in various clinical facets of oral cancer. The first section demonstrates the utilization of omics data and ML to disentangle the impediments related to diagnosis. This includes the application of technology-based strategies to optimize early detection, classification, and staging via uncovering biomarkers and molecular signatures. Furthermore, breakthrough concepts such as salivaomics-driven non-invasive biomarker discovery and omics-complemented surgical interventions are articulated in detail. In the following part, the identification of novel disease-specific targets alongside potential therapeutic agents to confront oral cancer via omics-based methodologies is presented. Additionally, a special emphasis is placed on drug resistance, precision medicine, and drug repurposing. In the final section, we discuss the research approaches oriented toward unveiling the prognostic biomarkers and constructing prediction models to capture the metastatic potential of the tumors. Overall, we intend to provide a bird’s eye view of the various omics, bioinformatics, and ML approaches currently being used in oral cancer research through relevant case studies.