Cooper

Scatter factor/hepatocyte growth factor is a pleiotropic growth factor that binds to c-Met, a proto-oncogene encoded tyrosine kinase receptor ubiquitously present on most malignant gliomas. This grant application seeks to infuse thawed allogeneic T cells that have been rendered c-Met-specific for the treatment of gliomas.  

Buidling upon on our experience infusing autologous and allogeneic T cells genetically modified to express a chimeric antigen receptor (CAR) to redirect specificity for a desired cell-surface antigen (such as CD19 on B-cell malignancies) and our novel platform technologies that have been adapted for clinical translation using (i) the Sleeping Beauty (SB) transposon/transposase system to stably express CAR transgenes and (ii) artificial antigen presenting cells (aAPC) derived from K562 cells to propagate genetically modified T cells in a CAR-dependent manner to clinically-sufficient numbers.  

We have designed a 2nd generation CAR, designated cMetRCD28, to render T cells specific for c-Met independent of MHC. To conditionally activate cMetRCD28+ T cells under conditions of hypoxia thereby limiting deleterious targeting of normal tissues expressing c-Met, this CAR has been fused to the oxygen-dependent degradation domain (ODDD) which results in degradation of cell-surface CAR-ODDD protein under conditions of normoxia, but not hypoxia found in the tumor microenvironment.  

To generate allogeneic T cells from a 3rd party to be infused “on demand” we will co-express the CAR-ODDD with designer zinc finger nuclease (ZFN) (or inhibiting RNA species) to eliminate endogenous expression of alpha/beta T-cell receptor (TCR). The cMetRCD28-ODDD and ZFN transgenes will be electro-transferred into T cells using the SB system and selectively propagated on c-Met+ aAPC.  

This approach will be further developed to co-express a mutein of thymidine kinase (sr39TK) from herpes simplex virus-1 for in vivo conditional ablation with ganciclovir and imaging by positron emission tomography (PET). Aim #1 evaluates whether cMetRCD28+TK+TCRneg T cells lyse gliomas. The ability for these T cells to survive/propagate under hypoxia will be determined.  

Aim #2 evaluates the ability of cMetRCD28+TK+TCRneg T cells to selectively eliminate hypoxic c-Met+ glioma in an orthotopic xenogeneic mouse tumor model, using bioluminescent imaging and micro-PET to asses T-cell persistence and anti-tumor effect. Aim #3 evaluates in a human Phase I clinical trial the safety, feasibility, persistence and efficacy of thawed allogeneic cMetRCD28+TK+TCRneg T cells delivered loco-regionally after initial resection. PET/CT imaging using [18F]-FHBG metabolized by sr39TK will be used to evaluate the distribution of adoptively transferred T cells.  

In aggregate, these studies will develop new targeted cell and gene therapy for gliomas using our established clinical platform technologies and as c-Met is expressed on many extra-cranial solid tumors this approach may have broad application.  

Ryman

Recently, the use of tumor-killing viruses has gained favor in cancer gene therapy in an approach that has become known as “virotherapy.” Virotherapy exploits viruses that are able to target and destroy cancer cells, while sparing the surrounding normal tissue. We are developing a virotherapy approach for the treatment of prostate cancer based on infection with Sindbis virus.  

The ability of Sindbis virus to travel rapidly throughout the body in the bloodstream will improve access to metastasized cancer cells. We intend first to develop and test these agents in cultured cells. We will then test and optimize the ability of the virus to cure prostate cancer.

Lane

Since most human tumors must recruit new blood vessels in order to grow and move, anti-angiogenic therapies have been viewed as a potential complement to more traditional cancer treatments. We have identified a genetic element that allows genes to be expressed in a group of bone marrow derived cells that contribute to cancer-associated blood vessels.  

The cells are called “endothelial cell precursors” (ECPs). ECPs are a special type of stem cell that play a role in the formation of new blood vessels. We propose to create a simple virus designed to carry genes to ECPs and prevent them from helping tumors to grow. 

Vonderheide

A promising approach in cancer treatment is to vaccinate patients against molecules expressed by cancer in hopes of starting or awakening an immune response that will kill tumor cells. One leading strategy bases the center of such vaccines on the patient’s own immune cells, which are removed from the body and re-engineered outside the body before re-injection.  

With this grant, we will evaluate a novel gene therapy vaccine specifically designed for children with cancer, for whom very few attempts at cancer vaccination have been undertaken. This work will establish the scientific and manufacturing rationale for translating this gene therapy technology to the clinic, especially for children with cancer.