Research Funding

Year Funded: 2013

Characterization of Potential Antigens for Immunization Against Colon Cancer, and Testing Multivalent Tumor Vaccines in Min Mice

Grant Number: OUHSC-RS2O122 159-02

The successful identification of novel tumor antigens is critical to cancer immunotherapy and its potential use in cancer prevention. Colon cancer is the third most common cancer both in men and women and is the second most common cause of cancer death. Mouse models that mimic human disease provide a unique tool for tumor antigen discovery. In the past, multiple groups have used a variety of rodent models of colon cancer (Min, AOM Mouse, AOM Rat) to examine colon cancer development, potential agents that can prevent cancer development (e.g. NSAIDs) etc. In a more limited number of cases, they have used these models to examine the role of the immune response and even to make initial examination of immunization against colon cancer.

There are a variety of approaches towards deciding upon antigens which might be employed to develop a vaccine. In the rare cases where there is a highly over expressed protein that appears to be directly associated with tumor development e.g. Neu in Neu over expressing tumors this appears to be a promising approach both in animal models and clinically. A second is to pick antigens which are over expressed in both model and human tumors and which appear to be associated with the tumor process. It is this latter approach that will be employed here.

The specific animal model that will be employed here is a modified Min model. Although the standard Min model, on a C57BL6 background, has proven effective in screening potential chemopreventive agent it has a major limitation for vaccine work. The adenomas arise quite rapidly so that an animal will already have multiple adenomas at the time that immunization is initiated. To overcome this, the Contractor shall employ an F1 Min mouse (C57BlxAKR). In this case tumors come up more slowly which allows for initial immunization of animals with minimal tumor burden. Furthermore, animals survive long enough that they develop adenocarcinomas in the small intestine and a significant number of lesions of the colon unlike the standard Min mice.

Enhancing innate immunity by combining PSK with docetaxel in prostate cancer

Grant Number: H34B12-07 Prime: 1U19AT006028

Bastyr University collaboration for the University of Washington Immunologic

Monitoring Lab to accomplish the scientific aim of immune monitoring of blood samples for the

Bastyr/University of Washington PSK® prostate cancer clinical trial.

Year Funded: 2012

Optimized ex vivo expansion of anti-tumor Th1 and Tc1 for adoptive immunotherapy

Grant Number: CA136632

Recent clinical trials have demonstrated that advanced melanoma can be treated with a combination of nonmyeloablative chemotherapy and autologous adoptive T cell immunotherapy (AIT) to achieve a 50% clinical response rate. Such clinical responses are not, however, consistently durable. Cytotoxic T cells (CTL) are shortlived in the absence of T cell help (Th), with limited persistence after infusion. Furthermore, antigen (Ag) negative variants develop after infusion of CD8+ predominant tumor specific T cell lines, suggesting tumors readily escape from focused therapy. Our goal is to optimize and extend AIT to advanced breast cancer by providing functionally characterized tumor Ag-specific CD4+ Th1 cells as a central component of the infused product. Tumor Ag-specific CD4+ Th1 cells can home to tumor and secrete inflammatory cytokines, modulating the microenvironment to enhance the function of local antigen presenting cells (APC). The resultant increased processing of endogenous tumor cells results in epitope spreading. By providing a robust CD4+ Th1 immune response, tumor Ag-specific CD8+ T cells will be elicited, and the response generated will be long lived. We aim to promote tumor-specific, epitope spreading, Th1-type CD4+ responses as an essential component of effective AIT. This strategy has been validated by our own vaccine trials for Stage III/IV patients with HER-2/neu (HER2)-overexpressing breast cancer. Patients vaccinated with MHC Class II-binding HER2-derived peptides evidenced a significant survival advantage if they achieved not only enhanced CD4+ T cell responses to vaccine peptides, but also T cell responses to additional HER2 epitopes expressed by their tumors but absent from the vaccine. In animal studies we observe that the inclusion of autologous dendritic cells (DCs) during T cell culture can markedly improve T cell therapeutic performance at the time of re-infusion. Moreover, appropriately activated DCs can promote the expansion of T cells with higher functional avidity, including CD8+ cytolytic T cells that can directly lyse MHC-restricted tumors. We propose to develop a clinically relevant method to expand HER2 specific T cells ex vivo, using optimally activated autologous DC generated simultaneously in the same cultures as the T cells to be activated. We will also assess whether these culture methods increase epitope spreading.

Year Funded: 2011

Adoptive transfer of tumor specific Th1 cells derived from vaccine-primed patients achieved clinical benefits

Grant Number: Rivkin

Adoptive immunotherapy (AIT) can induce cancer regression but rarely results in cure. We have infused HER2 specific Th1 cells in breast cancer patients and a 50% overall objective response was observed. We hypothesize that polyfunctional tumor antigen-specific Th1/Th17 cells have enhanced therapeutic efficacy. We will determine the optimal conditions to expand the multifunctional T cells ex vivo and examine the efficacy and safety of infusion of IGFBP2 specific multifunctional T cells in a mouse model of human ovarian cancer. This study will lead to a phase I study of AIT in ovarian cancer after priming with an IGFBP2 vaccine.

Phase I-II Study of HER2 Vaccination with Ampligen as Adjuvant in Optimally Treated Breast Cancer Patients

Grant Number: Hemispherx

Due to recent advances in the conventional treatment of breast cancer (BC), BC patients are frequently able to achieve a state of complete remission with current primary therapies. However, approximately 30% of patients will eventually have recurrent disease, with the majority of recurrences being to metastatic sites; suggesting that relapse is due to residual microscopic disease. This is especially true in HER2+ BC patients who have worse disease-free and overall survival when compared to similar HER2 negative patients. One approach to the eradication of residual subclinical disease in this high-risk population is the development of tumor vaccines that target HER2, an immunogenic biologically relevant protein. Generation of vaccine-induced HER2-specific Type I inflammatory CD4+ T helper immunity (Th1) could result in immunologic eradication of residual HER2+ tumor cells and potentially prevent disease relapse or tumor spread.

We have demonstrated the ability to induce HER2-specific Th1 immunity and epitope spreading in breast cancer patients vaccinated with HER2 peptide-based vaccines given intradermally in combination with GM-CSF as adjuvant. Given the importance of Th1 immunity and its role in generating antigen-specific inflammatory responses, it is critical to investigate other vaccine adjuvants that can augment both development and magnitude of Th1 HER2-specific immunity. One such potential adjuvant is Ampligen [poly(I) • poly(C12,U)] which mediates its immunomodulating activity exclusively as a TLR-3 agonist.

We hypothesize HER2 peptide-based vaccination given in combination with GM-CSF and Ampligen can induce a higher incidence and magnitude of HER2-specific Th1 immunity than HER2 vaccination with GM-CSF alone. The aims of this study are to: (1) choose the most promising of 4 different Ampligen doses as an adjuvant to HER2 vaccination, with respect to toxicity and immune response and (2) determine, using the optimal Ampligen dose from Aim 1, whether Ampligen increases the incidence and magnitude of vaccine immune response as compared to the standard GM-CSF adjuvant strategy.

Characterization Of Potential Antigens For Immunization And Testing Of A Vaccine Against Colon/Intestinal Cancer In Min Mice

Grant Number: HHSN261-200433001C

The successful identification of novel tumor antigens is critical to cancer immunotherapy and its potential use in cancer prevention. Colon cancer is the third most common cancer both in men and women and is the second most common cause of cancer death. Mouse models that mimic human disease provide a unique tool for tumor antigen discovery. In the past, multiple groups have used a variety of rodent models of colon cancer (Min, AOM Mouse, AOM Rat) to examine colon cancer development, potential agents that can prevent cancer development etc. In a more limited number of cases they have used these models to examine the role of the immune response and even to make initial examination of immunization against colon cancer. Three particular aspects of colon cancer and the relevant rodent cancer models make this particularly appealing. First the preponderance of colon tumors and human FAP are driven by alterations in the WNT pathway most typically truncating mutations in the APC gene. Thus, the driving process in most human colon cancers and in the rodent tumor models listed above are alterations in the WNT pathway. Probably reflecting this common pathway alteration microarray analyses of normal mucosa and lesions from humans as compared to mice show significant overlap with regards to gene expression pathways which are altered as well as with regards to various specific genes whose expression is altered between tumors and normal mucosa. This is potentially important since certain of these proteins may prove to be antigens which are potentially useful for developing a vaccine. Potentially the third aspect of colon cancer that makes it particularly appealing is that there is some significant literature implying that colon cancers are often associated with a significant immunologic infiltrate and that the extent of this infiltrate may have significant effects on the prognosis of the colon cancer.

There are a variety of approaches towards deciding upon antigens which might be employed to develop a vaccine. In the rare cases where there is a highly over expressed protein that appears to be directly associated with tumor development e.g. Neu in Neu over expressing tumors this appears to be a promising approach both in animal models and clinically. A second is to pick antigens which are over expressed in tumors and which appear to be associated with the tumor process. More recently there has been an attempt to determine whether within the group of over expressed antigens there may be some that have elicited either an antibody response (SEREX) or a T cell mediated response in individuals with the tumor or in the case of animal models who may have rejected a tumor. The particular appeal of these antigens is that individuals have responded to these proteins and by implication it may be easier to break tolerance against these specific antigens. This specific approach has been pursued in the MMTV-Neu model in mice.

The objective of this work assignment would be to:
(1) Based on expression data determine whether expression of specific proteins, as determined by RNA when comparing colon lesions and normal mucosa, is similar in human colon tumors and certain animal models ( Min mouse).
(2) Determine whether animals bearing intestinal lesions demonstrate immunologic responses as determined by SEREX or specific T cell reactivity against relevant antigens and compare this with relevant proteins which have elicited an immune response in persons bearing colon tumors.
(3) From these proteins develop four antigens which appear amenable to development as potential antigens in a multivalent vaccine.
(4) Test these antigens for their ability to elicit an immune response in min mice.
(5) Test the potential vaccine (4 antigens vs 2 antigens and 2 antigens) to inhibit tumor formation in Min mice
(6) Test the vaccine together with a sub-ideal dose of a chemopreventive agent e.g. Celecoxib.

Vaccine to Prevent Breast Cancer

Grant Number: W81XWH-11-1-0760

Vaccination directed against common human pathogens has been one of the most successful strategies used to prevent human disease. The success of infectious disease vaccines depends on immunizing people prior to exposure to the pathogen. If we could identify immunogenic proteins important for breast cancer initiation, a vaccine could be developed to prevent breast cancer. Our group has shown that upregulation of a breast cancer-associated protein can result in that protein becoming immunogenic. This observation has allowed prospective screening of proteins that are overexpressed and associated with cancer stem cells and/or epithelial to mesenchymal transformation (EMT) as vaccine candidates. Stem cells carry the ability to initiate and maintain breast cancers and are associated with self renewal and metastatic potential, and EMT may drive the acquisition of stem cell-like properties. Eliminating cells that had upregulated proteins associated with the cancer stem cell and EMT may eliminate breast cancer. Vaccine strategies designed to elicit tumor antigen specific T helper 1 (Th1) immunity have the potential to elicit epitope spreading, concurrently stimulate antigen specific cytotoxic (CTL) CD8+ T cells, and establish immunologic memory. Immunologic memory will ensure that the tissue destructive immune response will deploy whenever the antigen is expressed in the future. We propose to develop a multiantigen polyepitope Th vaccine targeting stem cell/EMT antigens for the prevention of breast cancer.

Year Funded: 2010

Development of a vaccine targeting triple negative breast cancer

Grant Number: W81XWH-10-1-0700

Background, Rationale and Significance:
The insulin-like growth factor (IGF) pathway plays an important role in breast cancer growth and metastasis. The IGF-I receptor (IGF-IR) is expressed in almost 50% of triple negative breast cancer (TNBC) and is often co-expressed with EGFR. Indeed, EGFR and IGF-IR have been shown to cooperate to regulate tumor growth and survival in epithelial cancers such as TNBC. TNBC, defined as estrogen (ER-) and progesterone (PR-) receptor and HER-2/neu receptor (HER2-) negative, can represent as much as 20% of all invasive breast cancers and is generally considered more clinically aggressive than other breast cancer phenotypes. Patients who develop metastatic TNBC have a shorter survival than patients with metastatic breast cancer of other subtypes. Thus, therapeutically targeting the IGF-IR signaling pathway is a promising approach to treat TNBC.
Preliminary studies from our laboratory demonstrate that IGF-IR is immunogenic in breast cancer patients and a potential target for active immunization. We have extensive experience in developing vaccine strategies designed to elicit Type I inflammatory CD4+ T helper immunity (Th1). A focus on eliciting CD4+ tumor specific Th1 cells with vaccination has several distinct advantages over immunization strategies designed to elicit predominantly CD8+ T cells. First, vaccine stimulated tumor antigen-specific CD4+ Th1 cells may home to the tumor and the inflammatory cytokines they secrete, such as IFN-gamma (g), may modulate the tumor microenvironment. Th1 cytokines enhance the function of local antigen presenting cells (APCs) and augment endogenous antigen presentation. Increased processing of endogenous tumor cells results in epitope spreading, the development of an immune response to the multiple immunogenic proteins expressed in the tumor. In addition, by providing a robust CD4+ Th1 T cell response, tumor-specific CD8+ T cells will be elicited and proliferate endogenously. Finally, antigen specific CD4+ T cells would provide the environment needed to enhance and sustain tumor specific T cell immune responses over time.

Study objective/hypothesis:
We hypothesize that vaccination with MHCII IGF-IR-specific peptides will induce an anti-tumor immune response in triple negative breast cancer. IGF-IR is nearly 100% homologous between mouse and man. We have established the anti-tumor effect of immunization by vaccinating with IGF-IR-specific peptides in a transgenic mouse model of breast cancer and confirmed that an IGF-IR specific antibody and T cell immune response can be elicited. Thus, active immunization targeting IGF-IR may induce immunologic effects resulting in inhibition of breast cancer growth.

Specific Aims:
(a) To identify putative Class II epitopes, derived from IGF-IR, that stimulate IGF-IR-specific T cells in patients with breast cancer.
Since vaccines generating an antigen specific CD4+ Th1 response may modulate the tumor microenvironment, we propose to identify IGF-IR peptides based on predicted high avidity binding across multiple class II alleles, determine whether IGF-IR-peptide specific T cell lines can recognize human recombinant IGF-IR protein presented endogenously by autologous APC and determine whether identified IGF-IR peptides stimulate T regulatory (Treg) cell proliferation.
(b) To evaluate the immunogenicity, therapeutic efficacy, and safety of an IGF-IR vaccine in a murine model of triple negative breast cancer.
Initial studies will analyze the immunogenicity and therapeutic efficacy of an IGF-IR-peptide based vaccine in the C3(1)Tag mouse model. Subsequent studies will establish which immune effector arm is essential for mediating therapeutic efficacy after immunization and if IGF-IR vaccination induces diabetes or other toxicities in immunized mice.

SPORE Project 2: Targeted Immunotherapy of breast cancer with central memory T cells

Grant Number: CA138293

Project 2: Targeted Immunotherapy of breast cancer with central memory T cells
The translational goal of this project is to evaluate the adoptive transfer of tumor-specific T cells derived or engineered from central memory cells to treat breast cancer. The immune system is designed to distinguish diseased from normal cells with exquisite specificity and sensitivity, and there is increasing evidence that tumor development and progression is restrained by adaptive host T cell responses to tumor-associated antigens. However, harnessing this activity to provide therapeutic benefit in breast cancer requires identifying antigens that are expressed by tumor cells and can be safely targeted, and developing methods to achieve potent and durable T cell immunity in patients. Many candidate tumor associated antigens have been discovered in breast cancer and we have focused on targeting the HER-2 oncoprotein and NY-BR-1. We have pursued the adoptive transfer of T cells specific for these antigens because this approach should allow for control of the specificity, function, and magnitude of the antitumor response, and could overcome obstacles that limit the endogenous host response, or T cell responses elicited by vaccination. The efficacy of adoptive T cell therapy in clinical trials for other human malignancies has been limited by the inability of tumor-specific effector cells that have been expanded in vitro to persist at high levels in vivo after adoptive transfer. Studies in our lab have demonstrated that the survival of adoptively transferred T cells is correlated with the differentiation state of the precursor T cell from which the T cells are derived. Effector cells isolated from central memory but not effector memory T cells provide persistent engraftment, migrate to memory T cell niches, function in vivo after adoptive transfer, and can be sustained at remarkably high levels by a short course of IL-15. This project will build on these findings and evaluate the adoptive transfer of T cells derived or engineered from central memory cells to treat breast cancer. The specific aims are:
1. To perform a phase I trial of adoptive T cell therapy with TCM-derived HER-2/neu (HER-2)-specific T cells following in vivo priming with a HER-2 peptide vaccine in patients with advanced HER-2+ breast cancer.
2. To engineer CD45RO+ CD62L+ TCM derived effector T cells through T cell receptor (TCR) gene transfer to express a TCR that targets NY-BR-1.
3. To perform a phase I study of adoptive T cell therapy with TCR modified TCM to target NY-BR-1 in patients with advanced NY-BR-1+ breast cancer.

Cancer Immunotherapy Trials Network Central Operations and Statistical Center

Grant Number: CA154967

The Cancer Immunotherapy Trials Network (CITN), a multi-institutional consortium, focuses on early-phase clinical trials that test immunotherapeutic agents and modalities to treat patients with cancer. The Central Operations and Statistical Center (COSC) of the CITN will be based at the Fred Hutchinson Cancer Research Center (FHCRC) in Seattle. Designed as a multiple PD/PI structure, the COSC will provide leadership and organizational resources, including infrastructure, statistical support, and protocol coordination, for up to 25 member institutions and tumor immunology laboratories throughout the US. The research goals include: (1) creating and managing the CITN COSC to run a network of leading investigators and institutions to conduct early-phase clinical trials to determine the safety, toxicity, and efficacy of promising agents and strategies to prevent and treat cancer by immune mechanisms; (2) initiating at least 15 phase I or early phase II trials over the course of the funding period that investigate the basic mechanisms of immune evasion and resistance of cancers as an integral part of clinical trials; and (3) integrating a number of tumor immunology laboratories into the CITN to enable the use of specimens obtained from patients on CITN clinical trials for immunomonitoring, biomarker development and credentialing, and facilitating an understanding of the biological mechanisms that underlie the results of the clinical trials through established experimental and analytical infrastructures. Following a mandate from the NIH, the CITN will proactively develop the best trials possible by making hard-to-get agents available to immunotherapy specialists at member sites. The multiple PD/PIs combine long and successful histories of multicenter clinical trial conduct, early-phase immunology and immunotherapy research, and good laboratory practice and monitoring. The CITN will model the best practices and collaborate directly with staff at the FHCRC-based HIV Vaccine Trials Network, an international consortium that conducts AIDS-related immunotherapeutic clinical trials. The CITN infrastructure is designed to introduce peer-reviewed, hypothesis-driven clinical trials of the best agents available with pharmaceutical-like efficiencies to increase the likelihood of success in treating patients with cancer.

Pages