Tumor microenvironment in CLL and MCL: pathogenesis, targets, and therapy

CLL 和 MCL 的肿瘤微环境：发病机制、靶点和治疗

• 批准号: 8149489
• 负责人: adrian u wiestner
• 金额: $ 50.16万
• 依托单位: NATIONAL HEART, LUNG, AND BLOOD INSTITUTE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8149489
• 关键词: Address; Affect; Anatomy; Antigens; Apoptosis; Apoptotic; BCL2L11 gene; Biological Process; Biology; Blood; Bone Marrow; CD44 gene; Chronic Lymphocytic Leukemia; Clinical; Clonal Evolution; Combination Drug Therapy; Conduct Clinical Trials; Cytogenetics; Cytotoxic Chemotherapy; Data; Disease Progression; Drug resistance; Event; Flow Cytometry; Gene Targeting; Genes; Hyaluronic Acid; In Vitro; Innovative Therapy; Leukemic Cell; Location; Lymphoid; MCL1 protein; Malignant Neoplasms; Mantle Cell Lymphoma; Mature B-Lymphocyte; Molecular; Noxae; Organ; Pathogenesis; Pathway interactions; Patients; Pharmaceutical Preparations; Phosphorylation; Pre-Clinical Model; Protein Family; Receptor Signaling; Receptors, Antigen, B-Cell; Role; SYK gene; Signal Pathway; Signal Transduction; Site; Staining method; Stains; Stress; Systems Biology; T-Lymphocyte; Testing; Therapeutic; Tissues; Translational Research; Tumor Biology; Tumor Burden; Up-Regulation; base; cytotoxic; drug sensitivity; fludarabine; host neoplasm interaction; human FRAP1 protein; improved; in vivo; inhibitor/antagonist; interest; lymph nodes; member; neoplastic cell; novel; receptor; small molecule; trafficking; tumor

Chronic lymphocytic leukemia (CLL), an incurable malignancy of mature B-lymphocytes involves blood, bone marrow, and secondary lymphoid organs. A role of the tissue microenvironment in the pathogenesis of CLL is hypothesized based on in vitro observations but its contribution in vivo remain ill-defined. To elucidate effects of tumor host interactions in vivo we purified tumor cells from 24 treatment nave patients. Samples were obtained concurrently from blood, bone marrow and/or lymph node and analyzed by gene expression profiling. We identified the lymph node as a key site in CLL pathogenesis. CLL cells in the lymph node showed upregulation of gene signatures indicating B-cell receptor (BCR) and NF-B activation. Consistent with antigen dependent BCR signaling and canonical NFB activation, we detected phosphorylation of SYK and IkBalpha, respectively. Expression of BCR target genes was stronger in clinically more aggressive CLL indicating more effective BCR signaling in this subtype in vivo. Tumor proliferation quantified by expression of E2F and c-MYC target genes and verified by Ki67 staining by flow cytometry was highest in lymph node and correlated with clinical disease progression. To allow modeling of pathogenic tumor-host interactions we have established a mouse model that will be instrumental in testing specific interventions. In a second study we have focused on the role of CD44 a receptor for hyaluronic acid. We showed that CD44 engagement protects CLL cells from spontaneous and fludarabine-induced apoptosis. The anti-apoptotic effect appears to be mediated through activation of the PI3K/Akt and MAPK/ERK pathways and increased MCL-1 protein levels. PI3K or MEK inhibitors as well as obatoclax, an antagonist of MCL-1, blocked the pro-survival effect of CD44. Furthermore, obatoclax sensitized CLL cells to fludarabine resulted in a synergistic drug effect. Our findings emphasize the therapeutic potential of PI3K/AKT or MAPK/ERK inhibitors and obatoclax for combination chemotherapy approaches that overcome the supportive effect of the tissue microenvironment on CLL cell survival and drug resistance. We have investigated the potential of ON 01910.Na (Onconova, Therapeutics) a novel non-ATP competitive compound that can inhibit the PI-3K/Akt/mTOR pathway. We found that ON 01910.Na induced apoptosis of the leukemic cells in all CLL samples tested, without affecting T-cell viability. ON 01910.Na was equal cytotoxic against CLL samples showing adverse biologic and cytogenetic features. To further delineate the biological processes underlying ON 01910.Na induced apoptosis, we performed Gene Expression Profiling (GEP) in CLL cells treated in vitro These studies identified ON 01910.Na as a promising agent in the treatment of CLL with an interesting dual mechanism of action: activation of apoptotic stress signals leading to Noxa and BIM up-regulation, combined with inhibition of the BCR/PI3K/AKT pathway that can block microenvironment-induced survival and proliferation signals. Based on these data we initiated a phase I clinical trial of ON 01910.Na. Our findings that tumor proliferation is a result of tumor host interactions in vivo and a key determinant of clinical outcome can redirect therapeutic efforts. First, inhibiting the trafficking of CLL cells to protective microenvironment niches may be able to deprive the tumor cells of essential signals and induce apoptosis or sensitize the tumor to the effect of cytotoxic therapy. Furthermore, targeting essential signaling pathways in the microenvironment with small molecules could inhibit proliferation of CLL cells and thereby not only shrink tumor burden but also reduce clonal evolution. We identify the BCR as a valid therapeutic target in vivo, and small molecules inhibiting BCR signaling indeed show promise in early clinical trials. Another implication of our study is that tumor biology differs between anatomic locations possibly affecting drug sensitivity. For example we found increased expression of BCL2A1, an NF-κB regulated gene in LN-resident cells. BCL2A1 is an anti-apoptotic member of the BCL-2 family of proteins that can confer resistance to BCL-2 inhibitors. Thus, the variable biology of CLL cells in the microenvironment presents therapeutic opportunities and challenges that we will aim to address in clinical trials with strong translational research components

慢性淋巴细胞性白血病（CLL），成熟的B淋巴细胞的无法治愈的恶性肿瘤涉及血液，骨髓和继发性淋巴机器人。基于体外观察结果，假设组织微环境在CLL发病机理中的作用，但其在体内的贡献仍然不确定。为了阐明体内肿瘤宿主相互作用的作用，我们从24例中殿患者中纯化了肿瘤细胞。从血液，骨髓和/或淋巴结同时获得样品，并通过基因表达分析分析。我们将淋巴结确定为CLL发病机理中的关键部位。淋巴结中的CLL细胞显示出表明B细胞受体（BCR）和NF-B激活的基因信号上调。与抗原依赖性的BCR信号和规范NFB激活一致，我们分别检测到SYK和IKBALPHA的磷酸化。 BCR靶基因的表达在临床上更具侵略性的CLL中更强，表明该亚型在体内的BCR信号传导更有效。通过E2F和C-MYC靶基因表达量化的肿瘤增殖，并通过流式细胞仪染色验证，在淋巴结中最高，与临床疾病进展相关。为了允许致病性肿瘤宿主相互作用进行建模，我们建立了一种小鼠模型，该模型将有助于测试特定干预措施。在第二项研究中，我们关注CD44 A受体在透明质酸中的作用。我们表明，CD44参与保护CLL细胞免受自发和氟达拉滨诱导的细胞凋亡的影响。抗凋亡作用似乎是通过激活PI3K/AKT和MAPK/ERK途径以及MCL-1蛋白水平升高而介导的。 PI3K或MEK抑制剂以及MCL-1的拮抗剂Obatoclax阻断了CD44的促生物效应。此外，obatoclax将CLL细胞与氟达滨敏化导致协同的药物作用。我们的发现强调了PI3K/AKT或MAPK/ERK抑制剂和obatoclax的治疗潜力，以克服组织微环境对CLL细胞存活和耐药性的支持作用。 我们已经研究了ON 01910的潜力。NA（ONCONOVA，THENAPEUTICS）一种新型的非ATP竞争化合物，可以抑制PI-3K/AKT/MTOR途径。我们发现，在01910上，NA诱导了所有测试的CLL样品中白血病细胞的凋亡，而不会影响T细胞活力。在01910上，Na对表现出不良生物学和细胞遗传学特征的CLL样品的细胞毒性相等。为了进一步描述01910的生物学过程。NNA诱导的凋亡，我们在体外处理的CLL细胞中进行了基因表达分析（GEP），这些研究在01910上鉴定为01910.NA作为一种有前途的药物，作为CLL治疗CLL的一种有前途的药物，并具有有趣的双重作用机制：与诺克斯氏症和诺克斯的激活相结合，以实现诺克斯和诺克斯的激活， BCR/PI3K/AKT途径可以阻止微环境引起的生存和增殖信号。基于这些数据，我们启动了一项在01910的I期临床试验。 我们的发现，肿瘤增殖是体内肿瘤宿主相互作用的结果，而临床结果的关键决定因素可以重新定向治疗效果。首先，抑制CLL细胞以保护性微环境壁ni的运输可能能够剥夺肿瘤细胞的基本信号，并诱导凋亡或使肿瘤对细胞毒性治疗的作用敏感。此外，用小分子靶向微环境中的基本信号通路可以抑制CLL细胞的增殖，从而不仅收缩肿瘤负担，而且还会减少克隆进化。我们将BCR识别为体内有效的治疗靶标，而抑制BCR信号传导的小分子确实在早期临床试验中显示出有望。 我们研究的另一个含义是，肿瘤生物学的解剖位置可能影响药物敏感性。例如，我们发现BCl2A1的表达增加，Bcl2a1是LN居民细胞中NF-κB调控基因的表达。 Bcl2a1是Bcl-2蛋白质家族的抗凋亡成员，可以赋予Bcl-2抑制剂。 因此，微环境中CLL细胞的可变生物学提出了我们将在临床试验中解决的治疗机会和挑战，并具有强大的转化研究成分