Several genes and pathways associated with oral squamous cell carcinoma (OSCC) are significant in terms of early detection and prognosis. The objective of this literature review is to evaluate the current research on molecular pathways and genes involved in oral cancer. Articles on the genes involved in oral cancer pathways were evaluated to identify potential biomarkers that can predict survival. In total, 36 articles were retrieved from internet databases, including EBSCO Host, Google Scholar, PubMed, and Science Direct, using the keywords "biomarker of oral cancer," "pathways of oral cancer," "genes involved in oral cancer," and "oral cancer pathways." A total of 36 studies related to OSCC were chosen. Most of the studies used cell lines, while others used archival tissues, few studies followed up the cases. Three major interlinked pathways found were the nuclear factor kappa B (NF-kB), PI3K-AKT, and Wnt pathways. The commonly mutated genes were cyclin D1 (CCND1), Rb, p53, FLJ10540, and TC21. The NF-kB, PI3K-AKT, and Wnt pathways are most frequently involved in the molecular pathogenesis of oral cancer. However, the CCND1, Rb, p53, FLJ10540, and TC21 genes were found to be more accurate in determining patients' overall survival. Polymerase chain reaction, immunohistochemistry, and immunoblotting were the commonly used detection methods.

Targeting cancer stem cell (CSC) subpopulation within the tumor remains an obstacle for specific therapy in head-and-neck squamous cell carcinoma (HNSCC). Few studies in the literature describe a panel of stem cell makers, however a distinct panel has not been put forth. This systematic review aims to enhance the knowledge of additional markers to accurately relate their expression to tumorigenesis, metastasis, and therapy resistance. Databases, including PubMed, Google Scholar, Ebsco, and Science Direct, were searched from 2010 to 2017 using various combinations of the following keywords: "Stem cell markers in HNSCC" and "chemoresistance and radioresistence in HNSCC." Original experimental studies (both in vitro and in vivo) published in English considering stem cell markers in HNSCC, were considered and included. We excluded articles on tumors other than HNSCC, reviews, editorial letters, book chapters, opinions, and abstracts from the analyses. Forty-two articles were included, in which 13 types of stem cell markers were identified. The most commonly expressed CSC markers were CD44, aldehyde dehydrogenase, and CD133, which were responsible for tumorigenesis, self-renewal, and therapy resistance, whereas NANOG, SOX-2, and OCT-4 were involved in metastasis and invasion. Identification of an accurate panel of CSC markers is the need of the hour as nonspecificity of the current markers poses a problem. Further studies with a large sample size would help validate the role of these CSC markers in HNSCC. These CSC proteins can be developed as therapeutic targets for HNSCC therapy, making future treatment modality more specific and effective.

Preclinical studies and clinical trials have emphasized the decisive role of lipid metabolism in tumor proliferation and metastasis. This systematic review aimed to explore the existing literature to evaluate the role and significance of the genes and pathways most commonly involved in the regulation of lipid metabolism in cancer. The literature search was performed as per Preferred Reporting Items for Systematic Reviews and Meta-analyses. Approximately 2396 research articles were initially selected, of which 215 were identified as potentially relevant for abstract review. Upon further scrutiny, 62 of the 215 studies were reviews, seminars, or presentations, and 44 were original study articles and were thus included in the systematic review. The predominant gene involved in lipid metabolism in cancer was stearoyl-coenzyme A desaturase 1 (SCD1), followed by fatty acid synthase (FASN). The pathway most commonly involved in lipid metabolism in cancer was the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signaling pathway, followed by the mitogen activated protein kinase (MAPK) pathway. SCD1 and FASN play significant roles in the initiation and progression of cancer and represent attractive targets for potentially effective anti-cancer treatment strategies. The regulation of cancer metabolism by the Akt kinases will be an interesting topic of future study.