Epigenetic Profiling of Oral Cancer Cells

描述（由申请人提供）：拟议的工作将评估一种创新技术，用于分析癌症启动细胞（也称为癌症干细胞），以识别可用于诊断的标记物，并识别可指导药物开发计划的分子靶标。口腔鳞状细胞癌（OSCC）在美国每年被诊断为122.5万例，在过去的5年里一直在稳步增长。OSCC在手术切除和放射治疗后，由于言语和吞咽困难而引起显著的发病率。此外，复发性和转移性OSCC对细胞毒性化疗反应较差。因此，仍然迫切需要有助于早期发现和开发具有更高治疗效果的新药物疗法的策略。口腔癌（以及其他癌症）的发展和进展依赖于一小群癌症干细胞，这些干细胞不仅可以在局部治疗后再生肿瘤，而且由于对标准化疗特别难治而导致癌症复发。提出的工作将应用一种新的肽阵列技术来分析口腔上皮细胞的裂解物

DESCRIPTION (provided by applicant): The proposed work will evaluate an innovative technology for profiling cancer initiator cells (also known as cancer stem cells) to identify markers that can be used in diagnostics and to identify molecular targets that can guide drug development programs. Oral squamous cell carcinoma (OSCC), which is diagnosed in > 25,000 patients in the US each year, has been steadily increasing over the past 5 years. OSCC causes significant morbidity as a result of speech and swallowing difficulties following surgical resectio and radiation treatment. Moreover, recurrent and metastatic OSCC is poorly responsive to cytotoxic chemotherapy. Hence, there remains a pressing need for strategies that aid earlier detection and for the development of new drug therapies that have higher treatment efficacy. The development and progression of oral cancers (among others) relies on a small population of cancer stem cells which can not only regenerate the tumor bulk following local treatment but also contribute to cancer recurrence by being particularly refractory to standard chemotherapy. The proposed work will apply a novel peptide array technology to profile lysates of oral epithelial cells, OSCC cells and OSCC cells that have undergone EMT to identify patterns of deacetylase activity that may underlie the CSC phenotype. The technology is based on the SAMDI mass spectrometry technique that uses matrix- assisted laser desorption-ionization mass spectrometry to analyze an array of peptides immobilized to self- assembled monolayers. SAMDI mass spectrometry detects the mass of the peptide-alkanethiolate conjugate and therefore can identify changes in acetylation of the peptides. The proposed work will apply this method to profile deacetylase activities in cell cultures and identify differences in the activity profiles between oral keratinocytes, OSCC cells, OSCC cells that have undergone EMT, and in CSCs. The first Aim will develop peptide arrays for profiling acetylation activities in cell lysate and will validate the reproducibility of the experiment for the lysate and will use selective inhibitors to parse the activities to understand which specific enzymes contribute to the activity profiles. The second aim will apply the arrays to compare the acetylation activities in OSCC cells to those present in the CSC population. The goal of this R21 proposal is to validate the use of the SAMDI technology for identifying molecular activities that underlie the generation and maintenance of cancer stem cells. The work has the broader goal of introducing an innovative strategy for understanding the regulation of cancer stem cells and may lead to new diagnostic approaches and targets for drug development.