[Expression of voltage-gated potassium channel Kv3.4 in oral squamous cell carcinoma]

To evaluate the expression of voltage-gated potassium channel Kv3.4 and to determine its significance in oral squamous cell carcinoma (OSCC) and precancerous lesions.

Immunohistochemical SP methods were performed to detect the expression of Kv3.4 at tissue level on 57 paraffin-embedded samples collected from Pathology Department of Anhui Province Stomatological Hospital during January 2013 to June 2014. The relationships between the expression of Kv3.4 and precancerous lesion and clinical pathologic factors of oral squamous cell carcinoma, such as pathologic classification, clinical stage and lymph node metastasis, were also analyzed. Totally 6 samples of normal oral mucosa tissue, 23 samples of OSCC and 13 samples of precancerous lesions were collected from the Department of Oral and Maxillofacial Surgery of The First Affiliated Hospital of Anhui Medical University during May 2014 to March 2015. Real-time quantitative PCR and Western blotting were used to detect the expression of Kv3.4 in these 42 samples at molecular and protein levels.

Real-time quantitative PCR showed the relative expression quantity of Kv3.4 in normal oral mucosa, precancerous lesions, and OSCC tissues were 0.85±0.48, 3.50±2.51 and 18.48±7.70, respectively. The relative expression quantity of Kv3.4 in OSCC and precancerous lesions were higher than that in normal group, the differences were both statistically significant (P=0.002, P=0.029). The relative expression quantities of Kv3.4 protein in precancerous and OSCC tissues were 0.87±0.14 and 0.35±0.03 respectively by Western blotting, and both were higher than that in normal tissues (0.18±0.10). The differences were statistically significant (P=0.002). In 57 paraffin-embedded samples, the positive expression rates of Kv3.4 in normal, precancerous and OSCC tissues were 2/6, 13/18 and 95% (37/39), respectively. The differences were statistically significant(P<0.05). However, the expression of Kv3.4 did not show obvious correlation with patients' genders, presence of lymph node metastasis and clinical stages (P>0.05).

The expression of Kv3.4 is positively correlated to OSCC's occurrence and development. Detection of the expression of Kv3.4 may be used for early diagnosis and prognostic judgment of oral squamous cell carcinoma and precancerous lesions.