Novel Targeted Therapy for Breast Cancer

乳腺癌新型靶向治疗

• 批准号: 8004858
• 负责人: Ginette Serrero
• 金额: $ 57.58万
• 依托单位: A AND G PHARMACEUTICAL, INC.
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-11 至 2012-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8004858
• 关键词: Address; Adverse effects; Affect; Antibodies; Antibody Formation; Benign; Binding; Biologic Characteristic; Biological; Breast Cancer Cell; Cell Line; Cell model; Cells; Cellular biology; Chinese Hamster Ovary Cell; Clinical; Clinical Trials; Clone Cells; Cloning; Complementary DNA; Contracts; Development; Disease; Doxorubicin; Drug Formulations; Drug Kinetics; Faslodex(ICI 182,780); Generations; Growth; Growth Factor; Human; Hybridomas; In Vitro; Incidence; Libraries; Light; Malignant Neoplasms; Mammary Gland Parenchyma; Mediating; Metabolic; Mus; Normal tissue morphology; Outcome; PC cell-derived growth factor; Patients; Performance; Phase; Play; Principal Investigator; Production; Productivity; Property; Recombinants; Research; Resistance; Roche brand of trastuzumab; Role; Safety; Serum; Small Business Innovation Research Grant; Tamoxifen; Therapeutic; Tissues; Tumorigenicity; Validation; Woman; advanced disease; angiogenesis; antigen binding; autocrine; base; cancer cell; cancer therapy; cell growth; chimeric antibody; clinical efficacy; design; expression vector; improved; in vivo; innovation; malignant breast neoplasm; malignant phenotype; mortality; neoplastic cell; neutralizing monoclonal antibodies; novel; outcome forecast; overexpression; pre-clinical; programs; public health relevance; research study; scale up; tumor; tumor growth; tumorigenesis

DESCRIPTION (provided by applicant): Breast cancer remains one of the top three cancers to affect and cause mortality in women. Major shortcomings with current treatment are the high level of side effects induced in patients and insufficient efficacy, particularly for patients with metastatic disease. Targeted cancer therapy is designed to treat only the cancer cells and minimize damage to healthy cells. These targets are critical to the tumor's malignant phenotype but not to the host's normal tissues, improving outcomes while minimizing systemic side effects. Anti-HER2, Herceptin, leads the way for targeted therapy in breast cancer with a much lower incidence of side effects and definite efficacy in a specific but small subset of patients. However, there is a clear need for additional therapeutic options including other novel targeted therapies. The 88 kDa autocrine growth factor called PC-Cell Derived Growth Factor (PCDGF), also known as granulin precursor (GP88), has been shown to play a critical role in breast cancer cell biology, exemplified by the following: 1) GP88 is an autocrine growth/survival factor for breast cancer cells, 2) increased GP88 expression in breast cancer cells is associated with increased tumorigenicity, 3) GP88 mediates tumor cell angiogenesis and invasiveness, 4) breast cancer cells overexpressing GP88 are resistant to current therapies - Tamoxifen, Faslodex, doxorubicin, 5) increased GP88 expression in breast cancer tissue correlates with clinical parameters of poor prognosis while normal and benign breast tissue are negative, 6) patients with poor prognosis have elevated GP88 serum levels. These experiments show the essential role that GP88 plays in breast cancer cell tumorigenesis and that the inhibition of GP88 expression or function leads to inhibition of tumor growth. These results highlight the importance of GP88 for targeted therapy of breast cancer via the development of anti-GP88 therapeutic neutralizing monoclonal antibodies (Mabs). Our Phase I research proposed to evaluate a library of murine anti-GP88 for antigen binding properties and for biological activity in GP88-dependent in vitro and in vivo functional tumor cell models. These Phase I specific aims were accomplished and resulted in the identification of anti-GP88 neutralizing Mabs with the in vitro and in vivo potency and efficacy to be candidates for targeted therapy in breast cancer to address a vitally important unmet clinical need. We have selected one Mab, AG1, for further pre-clinical development activities, specifically the generation and characterization of a recombinant Mab (chimerized and humanized Mabs). The following Specific Aims are proposed for this Phase II SBIR application: 1. Cloning of the cDNA encoding the variable sequences of the light chain and heavy chain of the antibody expressed by the AG1 hybridoma cells and generation of expression vectors for both a humanized (HuAG1) and a mouse-human chimeric antibody (ChAG1). 2. Transient expression of the HuAG1 and ChAG1 chimeric antibodies and validation of their binding properties. The antigen binding characteristics and biological activities of the cloned, expressed HuAG1 and ChAG1 will be evaluated and compared with the murine AG1 Mab in order to select candidate recombinant AG1 that fit acceptance criteria for further development. 3. Generate stable HuAG1- or ChAG1-producing cell clones. HuAG1 or ChAG1 selected above will be stably expressed in CHO cells. The HuAG1- or ChAG1-producing clones will be compared for cell growth performance, antibody productivity, and metabolic profile in order to select a candidate clone for scale-up production. 4. Express, purify and characterize the biological properties of the HuAG1 or ChAG1 Mab. The Mab will be evaluated in relevant in vitro and in vivo functional tumor cell models and compared directly with the murine AG1 Mab. GP88 represents a novel, pre-clinically validated target for breast cancer. At the conclusion of this research in this Phase II project, we will have generated a mouse/human chimeric Mab with the in vitro and in vivo pre-clinical efficacy and potency for targeted therapy of breast cancer and we will have developed an optimized clonal antibody production cell line suitable for transfer to a CMO for contract manufacturing. However, once this chimeric anti-GP88 Mab has been generated and characterized it will require further pre-clinical development activities (e.g. formulation, pharmacokinetics and safety) before IND filing for clinical trials in breast cancer. These additional development activities will serve as the basis for a subsequent continuation/renewal Phase II SBIR application. PUBLIC HEALTH RELEVANCE: Breast cancer remains one of the top three cancers to affect and cause mortality in women. Major shortcomings with current treatment are the high level of side effects induced in patients and insufficient efficacy, particularly for patients with advanced disease. The innovative breast cancer therapy to be developed in this proposal will target a mechanism inherent in breast cancer but avoid the side effects associated with many current breast cancer therapies.

描述(申请人提供)：乳腺癌仍然是影响和导致女性死亡的三大癌症之一。目前治疗的主要缺点是患者副作用高，疗效不足，特别是对转移性疾病患者。靶向癌症治疗的目的是只治疗癌细胞，并将对健康细胞的损害降至最低。这些靶点对肿瘤的恶性表型很关键，但对宿主的正常组织并不重要，在改善结果的同时将全身副作用降至最低。抗HER2，Herceptin是乳腺癌靶向治疗的领头羊，副作用发生率低得多，在特定但为数不多的患者中具有明确的疗效。然而，显然需要更多的治疗选择，包括其他新的靶向治疗。88 kDa的自分泌生长因子被称为pc细胞衍生生长因子，也被称为颗粒蛋白前体(Gp88)，已被证明在乳腺癌细胞生物学中起关键作用，例如：1)gp88是乳腺癌细胞的一种自分泌生长/存活因子，2)gp88在乳腺癌细胞中的表达增加与肿瘤的致瘤性增加有关，3)gp88介导肿瘤细胞的血管生成和侵袭性，4)过表达gp88的乳腺癌细胞对目前的治疗方法-他莫昔芬、Faslodex、阿霉素具有耐药性，5)在乳腺癌组织中gp88的表达增加与预后不良的临床参数有关，而正常和良性乳腺组织则为阴性。6)预后不良的患者血清GP88水平升高。这些实验表明，GP88在乳腺癌细胞的肿瘤发生中起着至关重要的作用，抑制GP88的表达或功能会抑制肿瘤的生长。这些结果强调了通过开发抗GP88的治疗性中和单抗(MAbs)，GP88对于乳腺癌靶向治疗的重要性。我们的第一阶段研究建议评估鼠抗GP88文库的抗原结合特性和在依赖GP88的体外和体内功能性肿瘤细胞模型中的生物学活性。这些第一阶段的特定目标已经实现，并导致了具有体外和体内效力的抗GP88中和单抗的鉴定，成为乳腺癌靶向治疗的候选对象，以满足至关重要的未得到满足的临床需求。我们已经选择了一种单抗AG1，用于进一步的临床前开发活动，特别是重组单抗的产生和特性(嵌合化和人源化的单抗)。1.克隆AG1杂交瘤细胞表达的抗体轻链和重链的可变区序列，构建人源化抗体(HuAG1)和人-鼠嵌合抗体(ChAG1)的表达载体。2.HuAG1和ChAG1嵌合抗体的瞬时表达及其结合特性的验证对克隆、表达的HuAG1和ChAG1的抗原结合特性和生物学活性进行评价，并与鼠源AG1单抗进行比较，以筛选出符合验收标准的候选重组AG1。3.获得稳定产生HuAG1或ChAG1的细胞克隆。以上选择的HuAG1或ChAG1将在CHO细胞中稳定表达。将对产生HuAG1或ChAG1的克隆的细胞生长性能、抗体产量和代谢谱进行比较，以选择用于扩大生产的候选克隆。4.表达、纯化和鉴定HuAG1或ChAG1单抗的生物学特性。该单抗将在相关的体外和体内功能肿瘤细胞模型中进行评估，并直接与小鼠AG1单抗进行比较。GP88代表了一种新的、临床前验证的乳腺癌靶点。在这个第二阶段项目的研究结束时，我们将产生一种具有体外和体内临床前疗效和潜能的人/鼠嵌合单抗，用于乳腺癌的靶向治疗，我们将开发出一种优化的克隆抗体生产细胞系，适合转移到CMO进行合同制造。然而，一旦这种嵌合的抗GP88单抗被产生和表征，在IND申请乳腺癌临床试验之前，它将需要进一步的临床前开发活动(例如配方、药代动力学和安全性)。这些额外的开发活动将作为后续续展/续展第二阶段SBIR应用的基础。 公共卫生相关性：乳腺癌仍然是影响和导致女性死亡的三大癌症之一。目前治疗的主要缺点是患者副作用高，疗效不足，特别是对晚期疾病患者。这项提案中将开发的创新乳腺癌疗法将针对乳腺癌固有的机制，但避免与目前许多乳腺癌疗法相关的副作用。