Identification of Potential Biomarker for Head and Neck Squamous Cell Carcinoma
Posted: Monday, October 21, 2019
The long noncoding RNA (lncRNA) CASC9 appears to be a potential biomarker for head and neck squamous cell carcinoma detection. CASC9 is regularly overexpressed in head and neck cancers, although it does not act as a driver of tumor progression. Dr. Michèle J. Hoffman, of Heinrich Heine University Dusseldorf, Germany, along with colleagues, published the study identifying this biomarker in BMC Cancer.
To identify CASC9, researchers mined public data sets such as The Cancer Genome Atlas for lncRNA candidates. Then, two different head and neck squamous cell carcinoma tissue sets and one bladder cancer tissue set were analyzed using quantitative reverse transcription polymerase chain reaction (RT-qPCR). The effects of lncRNA overexpression or downregulation on cell proliferation, clonogenicity, migration, and chemosensitivity were studied as well.
CASC9 was found to be significantly overexpressed in head and neck tumors, based on The Cancer Genome Atlas RNA-sequencing data. This overexpression was confirmed using RT-qPCR in the two head and neck tumor cohorts. It may be possible to use CASC9 expression to discriminate tumor tissue from normal tissue with higher specificity than HOTAIR, a previously hypothesized head and neck tumor biomarker. Combining HOTAIR and CASC9 increased the specificity of head and neck squamous cell carcinoma detection.
The Cancer Genome Atlas pan-cancer data showed increased expression of CASC9 in tumors originating from different sites such as the bladder, liver, lungs, and stomach. Using RT-qPCR again, researchers determined that CASC9 was more strongly overexpressed in pure squamous cell carcinoma of the bladder and mixed urothelial carcinoma with squamous differentiation compared with urothelial carcinoma. Therefore, CASC9 may serve as a general diagnostic biomarker for squamous cell carcinomas.
Of note, upregulation or downregulation of CASC9 in head and neck squamous cell carcinomas did not result in any significant change in cell viability, clonogenicity, migration, or chemosensitivity.
Disclosure: The study authors reported no conflicts of interest.