DNA hypermethylation markers of poor outcome in laryngeal cancer

Abstract

This study examined molecular (DNA hypermethylation), clinical, histopathological, demographical, smoking, and alcohol variables to assess diagnosis (early versus late stage) and prognosis (survival) outcomes in a retrospective primary laryngeal squamous cell carcinoma (LSCC) cohort. The study cohort of 79 primary LSCC was drawn from a multi-ethnic (37% African American), primary care patient population, diagnosed by surgical biopsies in the Henry Ford Health System from 1991-2004, and followed from 5-18 years (through 2009). Of the 41 variables, univariate risk factors of p<0.10 were tested in multivariate models (logistic regression {diagnosis} and Cox {survival} models {p<0.05}). Aberrant methylation of ESR1 (p=0.01), race as African American (p=0.04), and tumor necrosis (extensive) (p=0.02) were independent predictors of late stage LSCC. Independent predictors of poor survival included presence of vascular invasion (p=0.0009), late stage disease (p=0.03) and methylation of the HIC1 gene (p=0.0002). Aberrant methylation of ESR1 and HIC1 signified independent markers of poorer outcome. In this multi-ethnic, primary LSCC cohort, race remained a predictor of late stage disease supporting disparate diagnosis outcomes for African American patients with LSCC.

Fig. 1

a A normal control DNA sample generates 41 individual peaks for all probes in the absence of HhaI (red) and 15 separate peaks in the presence of HhaI (blue). b Aberrant methylation identified in tumor sample as the appearance of a signal peak that is otherwise absent in normal DNA samples, seen here for APC, CHFR, DAPK1, and ESR1

Fig. 2

Patients with vascular invasion (n = 8) had a significantly shorter survival time as compared to patients without vascular invasion (n = 69)

Fig. 3

Patients with late stage disease (n = 40, stage 3 and 4) had poorer survival as compared to those with early stage disease (n = 38, stage 0, 1, and 2)

Fig. 4

Methylation of HIC1 was an independent predictor of poorer survival. LSCC patients without HIC1 methylation (n = 74) had a median survival of 4.40 (range, 0.04 to 16.21) as compared to a median survival of 1.02 years (range, 0.044 to 2.88) for patients (n = 5) with HIC1 methylation