Possible implication of Mdm2 as a prognostic marker in invasive laryngeal carcinoma

Abstract

Laryngeal squamous cell carcinoma is one of the most common malignant neoplasms of the head and neck. In Brazil, laryngeal tumors represent 2% of all cancers and are associated with approximately 3,000 deaths annually. Human papillomavirus (HPV) has been reported to play an important role in the etiology of laryngeal cancer. The aim of the present study was to evaluate the expression of p53, p27, and Mdm2 in laryngeal carcinomas. Sixty-three larynx biopsies were selected for the study, including 9 in situ laryngeal carcinomas, 27 laryngeal carcinomas without metastasis and 27 laryngeal carcinomas with metastasis. Twenty-seven cervical lymph nodes from patients with metastatic lesions were also evaluated. The expression levels of p53, p27, and Mdm2 were assessed by immunohistochemistry using a computer-assisted system. HPV detection and typing were performed using PCR, and the HPV types that were evaluated included HPV 6, 11, 16, 18, 31 and 33. Out of 63 patients, 53 (84.1%) were positive for β-globin (internal control), and 10 (15.9%) were β-globin negative and therefore excluded from the evaluation. Thus, 7 (13.2%) out of 53 patients were HPV positive, and 46 (86.8%) out of 53 patients were HPV negative. Statistically significant differences (p < 0.05) in Mdm2 expression levels were observed in the in situ laryngeal carcinoma samples compared with the laryngeal carcinoma samples with metastasis. No statistically significant differences (p > 0.05) in either p53 or p27 expression levels were detected. These findings suggest that Mdm2 may be associated with the invasiveness and aggressiveness of laryngeal carcinomas.

Combined Effect of HPV and Several Gene SNPs in Laryngeal Cancer

“…A common malignancy found in the head and neck tumor is laryngeal squamous cell carcinoma (LSCC) [1,2], with 151,000 new cases diagnosed worldwide [3] each year and 90,000 associated deaths [4,5]. LSCC usually affects men over 50-60 years of age [6] and is strongly related with tobacco smoking and alcohol use [7]. Meanwhile, some infectious pathogens such as HPV may act as associated carcinogenic factors [8].…”

Benzo[a]pyrene induced p53-mediated cell cycle arrest, DNA repair, and apoptosis pathways in Chinese rare minnow (Gobiocypris rarus)

“…In this study, a significant increase in mdm2 gene transcription in the males and females was observed. Similarly, statistically significant differences in mdm2 expression levels were observed in laryngeal carcinoma samples (Hassumi‐Fukasawa et al, ). Our finding that p53 and mdm2 increased upon BaP exposure could be due to the auto‐regulatory feedback loop described in mammals for this complex of proteins (Soares et al, ).…”

Protein marker profiling in different T classification in laryngeal squamous cell carcinoma

“…The dysregulation of some of these proteins reported in head and neck cancer in previous studies was consistent with our findings. For example, PCNA, CDK2, and p27 were upregulated in laryngeal carcinoma, [7][8][9] and Bcl-xL, MMP9, HMG-1, and p38 were upregulated in head and neck cancer. [10][11][12][13] However, the expression of some of the proteins differed from that described in previous publications.…”