HSP based combinatorial immunotherapy in triple negative breast cancer

描述（由申请人提供）：治疗三阴性乳腺癌（TNBC）需要新的疗法。为了响应这种临床需求，该提议将测试靶向分化的TNBC细胞和TNBC癌症起始细胞（CIC）的新型组合策略的功效。后者被鉴定为ALDHbright细胞必须被根除，以“治愈”恶性疾病，因为根据癌症干细胞理论，这些细胞是疾病复发和转移的原因。选择作为靶标的肿瘤抗原是94 kDa的葡萄糖调节蛋白（Grp 94）。Grp 94调节与细胞增殖、存活和迁移相关的信号通路的激活。为了靶向Grp 94，我们将利用我们最近表征的人mAb W 9的独特特异性。mAb W 9识别在癌细胞（包括分化的TNBC细胞和TNBC CIC）上选择性表达的细胞外Grp 94表位，但在正常组织中具有有限的分布。mAb W 9在体外显著抑制TNBC和TNBC CIC增殖。为了增强其抗增殖活性，我们将mAb W 9与LDE 225组合，LDE 225是Sonic Hedgehog（SHH）途径的新型抑制剂，其在TNBC中，特别是在TNBC CIC中异常激活。mAb W 9增强了LDE 225抑制TNBC细胞体外生长的能力，并通过抑制参与TNBC细胞和TNBC CIC的细胞增殖和存活的信号传导途径来消除TNBC CIC。将通过以下特定目的评估体外结果的体内和潜在临床相关性： i）mAb W 9和LDE 225组合在根除原位移植有TNBC细胞系MDA-MB-231-Luc-D3 H1的严重联合免疫缺陷（SCID）小鼠中建立的TNBC肿瘤方面比单独的药剂更有效; ii）用TNBC细胞系MDA-MB-231-Luc-D3 H1获得的结果具有临床意义，因为它们在原位移植有从患者手术切除的TNBC肿瘤的SCID小鼠中重现。 概述的实验产生的结果将有助于确定mAb W 9是否应转移至临床环境。它的翻译将通过以下事实来促进： W 9是一种完全人源抗体，用于患者时不需要任何重大操作。此外，Isakoff博士接触他的TNBC患者及其进行临床试验的技能将促进这种新型组合策略的临床实施。

DESCRIPTION (provided by applicant): Novel therapies are need for the treatment of triple negative breast cancer (TNBC). In response to this clinical need, this proposal will test the efficacy of a novel combinatorial strategy which targets differentiated TNBC cells and TNBC cancer initiating cells (CICs). The latter identified as ALDHbright cells have to be eradicated in order to "cure" a malignant disease, since according to cancer stem cell theory these cells are responsible for disease recurrence and metastases. The tumor antigen selected as a target is the glucose-regulated protein of 94 kDa (Grp94). Grp94 regulates the activation of signaling pathways associated with cell proliferation, survival and migration. To target Grp94, we will take advantage of the unique specificity of the human mAb W9 we have recently characterized. mAb W9 recognizes an extracellular Grp94 epitope selectively expressed on cancer cells, including differentiated TNBC cells and TNBC CICs, but with a restricted distribution in normal tissues. mAb W9 markedly inhibits TNBC and TNBC CICs in vitro proliferation. To enhance its anti-proliferative activity we have combined mAb W9 with LDE225, a novel inhibitor of the Sonic Hedgehog (SHH) pathway which is aberrantly activated in TNBC and especially in TNBC CICs. mAb W9 enhances the ability of LDE225 in inhibiting TNBC cell in vitro growth, and in eliminating TNBC CICs by inhibiting signaling pathways involved in cell proliferation and survival of TNBC cells and TNBC CICs. The in vivo and potential clinical relevance of the in vitro results will be assessed by the following specific aims: i) mAb W9 and LDE225 combination is more effective than the individual agents in eradicating TNBC tumors established in Severe Combined Immunodeficiency (SCID) mice orthotopically grafted with the TNBC cell line MDA-MB-231-Luc-D3H1; ii) the results obtained with the TNBC cell line MDA-MB-231-Luc-D3H1 have clinical significance, as they are reproduced in SCID mice orthotopically grafted with TNBC tumors surgically removed from patients. The results generated by the outlined experiments will contribute to determine whether mAb W9 should be moved to a clinical setting. Its translation will be facilitated by the fact that the mAb W9 is a fully human antibody and does not require any major manipulation for use in patients. Furthermore, the clinical implementation of this novel combinatorial strategy will be facilitated b Dr. Isakoff's access to his patients with TNBC and his skills in conducting clinical trials.