Squamous cell carcinoma of the head and neck (HNSCC) represents 90% of all head and neck cancers (1). HNSCC is the 9th-most common cancer worldwide and is characterized by a high rate of recurrence after therapy, with a median 5-year survival range of 40-50% (1). Radiation resistance can arise when cells undergo sublethal damage during x-ray treatment, giving rise refractory post-treatment tumors with poor prognosis (2). Cellular models of HNSCC that demonstrate radiation-resistance are critical for elucidating factor associated with radio-resistance and advancing effective therapies.The SQ-20B human laryngeal squamous cell carcinoma cell line is a widely used model for radiation-resistant HNSCC. SQ-20B cells were derived from a laryngeal tumor (tumor stage 2 node stage 0) that presented following primary radiation therapy (2). The SQ-20B cell line harbors the c-raf proto-oncogene (3) associated with tumorigenicity and radio-resistance (4). SQ-20B cells have been characterized by expression of the SCC marker p63 (p40) (5). The characteristics of the SQ-20B cell line demonstrate its utility as a model for cellular mechanisms that give rise to radiation resistance.Source:The SQ-20B cell line was derived from a tumor on the larynx of a patient undergoing radiation therapy2 and harbors a male karyotype (3).Research Category:Cancer