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

基本信息

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
项目类别：
财政年份：
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

项目摘要

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

慢性淋巴细胞白血病 (CLL) 是一种无法治愈的成熟 B 淋巴细胞恶性肿瘤，累及血液、骨髓和次级淋巴器官。根据体外观察假设组织微环境在 CLL 发病机制中的作用，但其在体内的贡献仍不明确。为了阐明体内肿瘤宿主相互作用的影响，我们从 24 名未接受治疗的患者中纯化了肿瘤细胞。同时从血液、骨髓和/或淋巴结中获取样本，并通过基因表达谱进行分析。我们确定淋巴结是 CLL 发病机制的关键部位。淋巴结中的 CLL 细胞显示出基因特征上调，表明 B 细胞受体 (BCR) 和 NF-κB 激活。与抗原依赖性 BCR 信号传导和典型的 NFκB 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袭性的 CLL 中更强，表明该亚型体内的 BCR 信号传导更有效。通过 E2F 和 c-MYC 靶基因的表达进行量化并通过流式细胞术 Ki67 染色进行验证的肿瘤增殖在淋巴结中最高，并且与临床疾病进展相关。为了建立致病性肿瘤与宿主相互作用的模型，我们建立了一个小鼠模型，该模型将有助于测试特定的干预措施。在第二项研究中，我们重点关注透明质酸受体 CD44 的作用。我们发现 CD44 的参与可以保护 CLL 细胞免受自发性和氟达拉滨诱导的细胞凋亡。抗凋亡作用似乎是通过激活 PI3K/Akt 和 MAPK/ERK 通路以及增加 MCL-1 蛋白水平来介导的。 PI3K 或 MEK 抑制剂以及 obatoclax（MCL-1 的拮抗剂）可阻断 CD44 的促生存作用。此外，obatoclax 使 CLL 细胞对氟达拉滨敏感，从而产生协同药物效应。我们的研究结果强调了 PI3K/AKT 或 MAPK/ERK 抑制剂和 obatoclax 联合化疗方法的治疗潜力，克服了组织微环境对 CLL 细胞存活和耐药性的支持作用。我们研究了 ON 01910.Na（Onconova，Therapeutics）的潜力，这是一种新型非 ATP 竞争性化合物，可以抑制 PI-3K/Akt/mTOR 通路。我们发现 ON 01910.Na 在所有测试的 CLL 样本中诱导白血病细胞凋亡，而不影响 T 细胞活力。 ON 01910.Na 对显示不良生物学和细胞遗传学特征的 CLL 样本具有相同的细胞毒性。为了进一步描述 ON 01910.Na 诱导细胞凋亡的生物学过程，我们在体外处理的 CLL 细胞中进行了基因表达谱 (GEP)。这些研究确定 ON 01910.Na 是治疗 CLL 的有前途的药物，具有有趣的双重机制：作用：激活细胞凋亡应激信号，导致 Noxa 和 BIM 上调，同时抑制 BCR/PI3K/AKT 通路，从而阻断微环境诱导的生存和增殖信号。基于这些数据，我们启动了 ON 01910.Na 的 I 期临床试验。我们的发现是肿瘤增殖是体内肿瘤宿主相互作用的结果，并且是临床结果的关键决定因素，可以重新调整治疗努力。首先，抑制 CLL 细胞向保护性微环境生态位的运输可能能够剥夺肿瘤细胞的重要信号并诱导细胞凋亡或使肿瘤对细胞毒治疗的效果敏感。此外，用小分子靶向微环境中的重要信号通路可以抑制 CLL 细胞的增殖，从而不仅缩小肿瘤负担，还可以减少克隆进化。我们将 BCR 确定为体内有效的治疗靶点，抑制 BCR 信号传导的小分子确实在早期临床试验中显示出前景。我们研究的另一个含义是解剖位置之间的肿瘤生物学差异可能会影响药物敏感性。例如，我们发现 LN 驻留细胞中 NF-κB 调节基因 BCL2A1 的表达增加。 BCL2A1 是 BCL-2 蛋白家族的抗凋亡成员，可赋予对 BCL-2 抑制剂的抗性。因此，微环境中 CLL 细胞的可变生物学特性带来了治疗机遇和挑战，我们的目标是在具有强大转化研究成分的临床试验中解决这些机遇和挑战