Identification of key miRNAs and targeted genes involved in the progression of oral squamous cell carcinoma

MicroRNA-34a-3p and its target tumor necrosis factor-α in the regulation of South Indian oral squamous cell carcinoma population

BACKGROUND

The most frequent head and neck cancer is oral squamous cell carcinoma (OSCC), the common histological cancer of the oral cavity and is one of the most prevalent forms of cancer globally. It has been known that there are several biomarkers and therapeutic targets that have been discovered for OSCC, but none of them were effective against the progression of OSCC. Interestingly, small non-coding RNAs termed microRNAs (miRNAs) regulate cellular activity by targeting numerous signaling pathways or genes that either promote or repress the progression of diseases. Surprisingly, among the differentially expressed miRNAs, miR-34a was identified to be highly sensitive and specific to OSCC and widely studied for its role in various cancers, including OSCC.

METHODS

The secondary structure of miR-34a-3p was analyzed using bioinformatic analysis and its targets were screened using the TargetScan database. Specimens of 25 OSCC cancer tissues and adjacent normal tissues were collected from the Department of Oral and Maxillofacial Surgery, Saveetha Dental College and Hospitals. The tissues were processed for H&E staining and gene expression analysis of miR-34a-3p and tumor necrosis factor alpha (TNF-α).

RESULTS

The minimum free energy for miR-34a-3p was found to be -47.20 kCal which proved the stability of the miRNA. The histopathological examination confirmed the OSCC cases and the gene expression analysis revealed that miR-34a-3p was significantly downregulated in OSCC tissues, whereas TNF-α showed vice versa expression.

CONCLUSIONS

miR-34a-3p could be postulated as a potential therapeutic target for OSCC.

Identification of candidate target genes of oral squamous cell carcinoma using high-throughput RNA-Seq data and in silico studies of their interaction with naturally occurring bioactive compounds

Oral Squamous Cell Carcinoma (OSCC) accounts for more than 90% of all kinds of oral neoplasms that develop in the oral cavity. It is a type of malignancy that shows high morbidity and recurrence rate, but data on the disease's target genes and biomarkers is still insufficient. In this study, in silico studies have been performed to find out the novel target genes and their potential therapeutic inhibitors for the effective and efficient treatment of OSCC. The DESeq2 package of RStudio was used in the current investigation to screen and identify differentially expressed genes for OSCC. As a result of gene expression analysis, the top 10 novel genes were identified using the Cytohubba plugin of Cytoscape, and among them, the ubiquitin-conjugating enzyme (UBE2D1) was found to be upregulated and playing a significant role in the progression of human oral cancers. Following this, naturally occurring compounds were virtually evaluated and simulated against the discovered novel target as prospective drugs utilizing the Maestro, Schrodinger, and Gromacs software. In a simulated screening of naturally occurring potential inhibitors against the novel target UBE2D1, Epigallocatechin 3-gallate, Quercetin, Luteoline, Curcumin, and Baicalein were identified as potent inhibitors. Novel identified gene UBE2D1 has a significant role in the proliferation of human cancers through suppression of 'guardian of genome' p53 via ubiquitination dependent pathway. Therefore, the treatment of OSCC may benefit significantly from targeting this gene and its discovered naturally occurring inhibitors.Communicated by Ramaswamy H. Sarma.

Identification of RAS-like oncoprotein B (RALB) as a potential prognostic and therapeutic target in head and neck squamous cell carcinoma

BACKGROUND/PURPOSE

The RAS superfamily oncogenes play significant roles in various types of malignant tumors. However, little is known about the role of RAS-like oncoprotein B (RALB) in head and neck squamous cell carcinoma (HNSCC). This study evaluated whether RALB can be a prognostic and therapeutic target for HNSCC.

MATERIALS AND METHODS

A total of 504 HNSCC samples from The Cancer Genome Atlas database were segregated into two groups: RALB-high and RALB-low. The clinical significance of RALB expression in HNSCC patients was investigated. Cell proliferation, migration, and invasion assays were performed in HN-1 and HN-5 cells by silencing RALB using siRNA. Gene enrichment and immune infiltration analyses were also performed.

RESULTS

RALB expression was elevated in HNSCC tissues compared with normal tissues and was an independent risk factor associated with poor prognosis. A nomogram including the RALB expression level was established to predict the prognosis of HNSCC patients and showed highest sensitivity and benefit in predicting the three-year survival. The inhibition of RALB expression effectively impeded the proliferation, invasion, and migration of HNSCC cells. Importantly, RALB levels were significantly correlated with T cell-mediated immune responses, especially in human papillomavirus-positive HNSCC samples.

CONCLUSION

This study identified RALB as a potential prognostic and therapeutic target for HNSCC, and provided insight into the relationship between RALB and revealed an innovative strategy for HNSCC immunotherapy.

[Advances in salivary exosomal miRNAs in head and neck squamous carcinoma]

Salivary exosomes are extracellular vesicles of 30-150 nm in diameter that exist in saliva and play an important role in substance exchange and signal transduction between cells, delivering the lipids, proteins and nucleic acids they carry to the recipient cells and regulating the physiological and pathological processes of the recipient cells. miRNA, as an important "cargo" in exosomes, is transported to the recipient cells and regulates the signaling pathways of the recipient cells, thus playing a regulatory role in disease progression. The miRNAs are transported to the recipient cells and regulate the signaling pathways of the recipient cells, thus playing a regulatory role in the progression of diseases. With the development of technological tools this year, numerous studies have revealed the important role of salivary exosomal miRNAs in the development of head and neck squamous carcinoma and the role of salivary exosomal miRNAs in the diagnosis and treatment of head and neck squamous carcinoma. This paper reviews the occurrence, treatment and prognosis of salivary exosomal miRNA in head and neck squamous carcinoma, and discusses the potential prospects and importance of salivary exosomal miRNA as a biomarker in the diagnosis of head and neck squamous carcinoma.

Association of salivary miRNAs with onset and progression of oral potentially malignant disorders: Searching for noninvasive biomarkers

Background/purpose

There is an urgent need for noninvasive biomarkers to diagnose oral potentially malignant disorders (OPMD). A wide range of over 20 miRNAs in saliva of OPMD patients have been investigated in different studies. Yet, which of the ones provide a better power of discrimination for the diagnosis of OPMD onset and progression are uncertain.

Materials and methods

A total of 17 eligible studies including 426 cases of OPMD and 486 control subjects (352 normal mucosa and 134 oral squamous cell carcinoma) were summarized.

Results

The bubble chart analysis showed that the most power salivary miRNA associated with OPMD onset was miR-21, followed by miR-31 and miR-142; the better power miRNAs associated with recurrence and malignant progression of OPMD were miR-31, miR-21, and miR-184.

Conclusion

Salivary miRNAs, especially miR-21 and miR-31, were associated with onset and progression of OPMD, and could then serve as noninvasive biomarkers for screening OPMD and detecting malignant changes.