PROGNOSTIC SIGNIFICANCE AND ANALYSIS OF iNOS IN MELANOMA

黑色素瘤中 iNOS 的预后意义和分析

• 批准号: 6993428
• 负责人: ELIZABETH A GRIMM
• 金额: $ 15.74万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-09 至 2009-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6993428
• 关键词: biomarker; enzyme activity; enzyme induction /repression; gene mutation; genetic transcription; human subject; human tissue; melanoma; metastasis; mitogen activated protein kinase; neoplasm /cancer classification /staging; neoplasm /cancer genetics; neoplastic process; nitric oxide synthase; nuclear factor kappa beta; patient oriented research; prognosis; protein quantitation /detection; protooncogene; tyrosine

Current data suggest that the process of melanoma tumorigenesis is enhanced by aberrant constitutive expression of the inducible form of nitric oxide synthase (iNOS), an enzyme catalyzing the generation of nitric oxide (NO), normally in response to cytokines. The presence of reactive NO in melanoma is indicated by detection of nitrotyrosine (NT), which is an end-product of the chemical reaction of NO with proteins; NT formation is known to alter intracellular signaling, especially when the target is a tyrosine kinase substrate. Production of low levels (pM) of NO by human tumors is proposed to be responsible for increased angiogenesis, growth, invasion, genomic instability and resistance to apoptosis. Our analysis of human melanoma specimens from patients with advanced (Stage III) disease indicates that patients whose tumors express iNOS are more likely to die within 2 years of neoadjuvant biohemotherapy than patients without iNOS (p<0.001). Specific Aim 1 comes from the clinic to the laboratory to further test the significance of iNOS and NT in tissue specimens as prognostic markers for primary and metastatic melanoma patients. The translational goals of Specific Aim 1 are validation of iNOS and NT as new prognostic markers for survival in melanoma patients and to determine whether either marker provides independent prognostic value. Significant results will then be submitted to American Joint Commission on Cancer, Committee on Melanoma for inclusion in future staging revisions, as the first molecular marker for melanoma to be validated. Specific Aim 2 tests the hypothesis that iNOS is controlled by specific, identifiable gene transcriptional regulators including constitutively active NFKB. NFKB activation is known to regulate basal as well as cytokine-induced iNOS in normal human cells, however its role in regulation of melanoma iNOS is unknown. Specific Aim 3 builds on further upstream mechanisms of iNOS activation and tests the association and functional role of mutated B-raf, which is reported to drive MAPK independently of Ras in melanoma cells. A novel molecular heteroduplex analysis will be employed to detect mutated B-raf in paraffin-embedded tumor specimens, and study of its association with iNOS and constitutive NFKappaB. The regulation of mutated B-raf activity is also proposed in Specific Aim 4 as a means to regulate iNOS and, by extension, melanoma growth.

目前的数据表明，黑色素瘤肿瘤发生的过程是通过诱导型一氧化氮合酶（iNOS）的异常组成型表达增强的，iNOS是一种催化一氧化氮（NO）生成的酶，通常响应于细胞因子。通过检测硝基酪氨酸（NT）来指示黑色素瘤中反应性NO的存在，NT是NO与蛋白质化学反应的终产物;已知NT形成会改变细胞内信号传导，特别是当靶点是酪氨酸激酶底物时。 人类肿瘤产生低水平（pM）的NO被认为是导致血管生成、生长、侵袭、基因组不稳定性和对凋亡的抗性增加的原因。我们对晚期（III期）患者的人黑色素瘤标本的分析表明，肿瘤表达iNOS的患者比不表达iNOS的患者更可能在新辅助生物血液疗法的2年内死亡（p<0.001）。具体目标1从临床到实验室，进一步测试组织标本中iNOS和NT作为原发性和转移性黑色素瘤患者预后标志物的意义。 Specific Aim 1的翻译目标是验证iNOS和NT作为黑色素瘤患者生存的新预后标志物，并确定任一标志物是否提供独立的预后价值。然后将重要结果提交给美国癌症联合委员会黑色素瘤委员会，以纳入未来的分期修订，作为第一个被验证的黑色素瘤分子标记物。特异性目的2检验了iNOS受特异性、可识别的基因转录调节因子（包括组成型活性NF κ B）控制的假设。已知NF κ B活化调节正常人细胞中的基础以及烟碱诱导的iNOS，然而其在调节黑素瘤iNOS中的作用是未知的。特异性目的3建立在iNOS激活的进一步上游机制上，并测试了突变的B-raf的关联和功能作用，据报道，突变的B-raf独立于Ras驱动MAPK。 黑素瘤细胞。一种新的分子异源双链分析将用于检测石蜡包埋的肿瘤标本中突变的B-raf，并研究其与iNOS和组成性NF κ B的相关性。在特定目标4中也提出了突变的B-raf活性的调节作为调节iNOS的手段，并通过扩展调节黑色素瘤生长。