Role of apoptosis proteins survivin, BAX and BCL-XL in laryngeal squamous cell carcinoma progression

ABSTRACT

We used immunohistochemistry to investigate a potential role of SVV as an early predictor of malignant transformation in precancerous and cancerous lesions of the larynx, we also sought to examine the expression of Bcl-X[L] and Bax in laryngeal SCC analyze the relationships between their expression and prognostic factors including site, histological grade, clinical staging and lymph node metastasis. This study included 6 normal laryngeal mucosae, 7 dysplastic laryngeal epithelia, 5 in situ laryngeal carcinomas, and 32 hiopsied laryngeal SCC. Clinical evaluation was done. Specimens were forma I in-fixed, paraffin-embedded, stained with H and E, classified and graded according to WHO classification, [2005] and immunostained to detect Survivin and Bcl-X[L]. and Bax proteins using the avidinbiotin peroxidase method. Survivin expression gradually increased significantly 'with advance of laryngeal carcinoma through the sequence of dysplasia, in situ carcinoma and infiltrating carcinoma [P < 0.04]. There is a statistically significant increase in Survivin expression with increasing tumor grade [P < 0.03] and with advance in clinical staging [P < 0.01]. Regarding lymph node metastasis SVV was more expressed in laryngeal SCC exhibiting lymph node metastasis [P < 0.02]. Bax expression was decreased significantly in infiltrating laryngeal carcinoma [P < 0.04] compared with premalignant lesions of the larynx. In contrast, Bcl-X[L] was increased significantly with the advance of laryngeal. carcinoma through dysplasia, carcinoma sequence [P < 0.02]. There was no statistically significant difference in either Bax or Bcl-X[L] expression considering tumor differentiation, advanced clinical staging or lymph node metastasis. Survivin plays cm important role in the initiation of laryngeal cancer and its progression towards higher grades, invasion and metastasis. Bax and Bcl-X[L] play their role early in cancer initiation but have nothing to do as the tumor progresses to higher grades, infiltrates deeply, or giving lymph node metastasis