Virani Shama, Bellile Emily, Bradford Carol R, Carey Thomas E, Chepeha Douglas B, Colacino Justin A, Helman Joseph I, McHugh Jonathan B, Peterson Lisa A, Sartor Maureen A, Taylor Jeremy Mg, Walline Heather M, Wolf Greg T, Rozek Laura S
Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, USA.
Department of Biostatistics, University of Michigan, School of Public Health, Ann Arbor, MI, USA.
BMC Cancer. 2015 Oct 30;15:825. doi: 10.1186/s12885-015-1806-8.
HPV-associated HNSCCs have a distinct etiologic mechanism and better prognosis than those with non-HPV associated HNSCCs. However, even within the each group, there is heterogeneity in survival time. Here, we test the hypothesis that specific candidate gene methylation markers (CCNA1, NDN, CD1A, DCC, p16, GADD45A) are associated with tumor recurrence and survival, in a well-characterized, prospective, cohort of 346 HNSCC patients.
Kaplan-Meier curves were used to estimate survival time distributions. Multivariable Cox Proportional Hazards models were used to test associations between each methylation marker and OST/RPFT after adjusting for known or identified prognostic factors. Stratified Cox models included an interaction term between HPV and methylation marker to test for differences in the associations of the biomarker with OST or RPFT across HPV status.
Methylation markers were differentially associated with patient characteristics. DNA hypermethylation of NDN and CD1A was found to be significantly associated with overall survival time (OST) in all HNSCC patients (NDN hazard ratio (HR): 2.35, 95% CI: 1.40-3.94; CD1A HR: 1.31, 95% CI: 1.01-1.71). Stratification by HPV status revealed hypermethylation of CD1A was associated with better OST and recurrence/persistence-free time (RPFT) (OST HR: 3.34, 95% CI: 1.88-5.93; RPFT HR: 2.06, 95% CI: 1.21-3.49), while hypomethylation of CCNA1 was associated with increased RPFT in HPV (+) patients only (HR: 0.31, 95% CI: 0.13-0.74).
This study is the first to describe novel epigenetic alterations associated with survival in an unselected, prospectively collected, consecutive cohort of patients with HNSCC. DNA hypermethylation of NDN and CD1A was found to be significantly associated with increased overall survival time in all HNSCC patients. However, stratification by the important prognostic factor of HPV status revealed the immune marker, CD1A, and the cell cycle regulator, CCNA1 to be associated with prognosis in HPV (+) patients, specifically. Here, we identified novel methylation markers and specific, epigenetic molecular differences associated with HPV status, which warrant further investigation.
与非HPV相关的头颈部鳞状细胞癌（HNSCC）相比，HPV相关的HNSCC具有独特的病因机制和更好的预后。然而，即使在每组中，生存时间也存在异质性。在此，我们在一个特征明确的346例HNSCC患者的前瞻性队列中，检验特定候选基因甲基化标志物（CCNA1、NDN、CD1A、DCC、p16、GADD45A）与肿瘤复发和生存相关的假设。
采用Kaplan-Meier曲线估计生存时间分布。在调整已知或已确定的预后因素后，使用多变量Cox比例风险模型检验每个甲基化标志物与总生存期（OST）/无复发/持续时间（RPFT）之间的关联。分层Cox模型包括HPV与甲基化标志物之间的交互项，以检验生物标志物与不同HPV状态下的OST或RPFT关联的差异。
甲基化标志物与患者特征存在差异关联。在所有HNSCC患者中，发现NDN和CD1A的DNA高甲基化与总生存时间（OST）显著相关（NDN风险比（HR）：2.35，95%置信区间：1.40 - 3.94；CD1A HR：1.31，95%置信区间：1.01 - 1.71）。按HPV状态分层显示，CD1A的高甲基化与更好的OST和无复发/持续时间（RPFT）相关（OST HR：3.34，95%置信区间：1.88 - 5.93；RPFT HR：2.06，95%置信区间：1.21 - 3.49），而CCNA1的低甲基化仅与HPV（+）患者的RPFT增加相关（HR：0.31，95%置信区间：0.13 - 0.74）。
本研究首次描述了在未选择的、前瞻性收集的连续HNSCC患者队列中与生存相关的新型表观遗传改变。在所有HNSCC患者中，发现NDN和CD1A的DNA高甲基化与总生存时间增加显著相关。然而，按重要预后因素HPV状态分层显示，免疫标志物CD1A和细胞周期调节因子CCNA1特别与HPV（+）患者的预后相关。在此，我们鉴定了与HPV状态相关的新型甲基化标志物和特定的表观遗传分子差异，值得进一步研究。
