Laryngeal carcinoma is a common head and neck cancer with poor prognosis. Patients with laryngeal carcinoma usually present late leading to the reduced treatment efficacy and high rate of recurrence. Despite the advance in the use of molecular markers for monitoring human cancers in the past decades, there are still no reliable markers for use to screen laryngeal carcinoma and follow the patients after treatment. Epigenetics emerged as an important field in understanding the biology of the human malignancies. Epigenetic alterations refer to the dysregulation of gene, which do not involve the alterations of the DNA sequence. Major epigenetic changes including methylation imbalance, histone modification, and small RNA dysregulation could play a role in the development of human malignancies. Global epigenetic change is now regarded as a molecular signature of cancer. The characteristics and behavior of a cancer could be predicted based on the specific epigenetic pattern. We here provide a review on the understanding of epigenetic dysregulation in laryngeal carcinoma. Further knowledge on the initiation and progression of laryngeal carcinoma at epigenetic level could promote the translation of the knowledge to clinical use. 1. Introduction Head and neck squamous carcinoma is estimated to be the sixth most common malignant tumor worldwide. Of which, laryngeal carcinoma is the second most common head and neck squamous carcinoma [1]. According to the global cancer statistics in 2008, the age-standardized incidence rate (ranged from age 0–74) is 5.5 per 100,000 in men and 0.6 per 100,000 in women in developed areas; in less developed area, the incidence rate is 3.5 per 100,000 in men and 0.6 per 100,000 in women [2]. It is estimated that there are 12,740 new patients (male 10,160 and female 2,580, resp.) suffering from laryngeal carcinoma in the United States in 2011 (accounting for 0.7% of the total new cancer cases). It also accounts for about 0.6% estimated cancer-related deaths in the United States [3]. In Hong Kong, laryngeal carcinoma took the third place in the incidence of the head and neck cancer in 2009 [4]. Most of the laryngeal carcinoma patients are male [5]. Moreover, the majority of the patients lie in the middle-aged group [6]. The definite cause of laryngeal carcinoma is not yet determined, while some risk factors are believed to be linked with the development of the disease. Tobacco and alcohol consumption are the primary aetiologic factors [6–8]. Chronic laryngeal inflammation induced by irritants and prolonged voice abuse could also
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