Patients receiving immunotoxin cancer therapy are less likely to experience the deleterious side-effects associated with non-discriminate therapies such as chemotherapy or radiation therapy. Unfortunately, the continued administration of immunotoxins often leads to a reduced patient response due to the formation of neutralizing antibodies against immunogenic epitopes contained within Pseudomonas exotoxin A (PE).
Human mesothelin is overexpressed by various cancers such as synovial sarcoma, mesothelioma, and ovarian, lung, esophageal, and gastric cancers. This selective expression on certain cancers suggests that mesothelin is an excellent target for anticancer therapeutics. However, a large fragment (“the shed portion”) of mesothelin is constantly shed from cells, and all current anti-mesothelin antibodies bind to the shed portion.
Targeted toxins (e.g., immunotoxins) are therapeutics that have at least two important components: (1) a toxin domain that is capable of killing cells and (2) a targeting domain that is capable of selectively localizing the toxic domain to only those cells which should be killed. By selecting a targeting domain that binds only to certain diseased cells (e.g., a cell which only expresses a cell surface receptor when in a diseased state), targeted toxins can kill the diseased cells while allowing healthy, essential cells to survive.
Recombinant immunotoxins (RITs) constitute a promising solution to hematologic cancers (e.g., Multiple Myeloma [MM]). RITs are chimeric proteins composed of a targeting domain fused to a bacterial toxin. Upon binding to a cancer cell displaying the target antigen, RITs are internalized, metabolized and the released toxin kills the cell. While highly active and effective, current RITs have short half-lives, requiring them to be used in high concentrations for treatment. At such high concentrations, RITs may show nonspecific activity and kill healthy cells.
Researchers at the National Cancer Institute (NCI) have developed orthotopic allograft models for pancreatic cancer that utilize low passage primary pancreatic adenocarcinoma cells or tumor fragments implanted into the cancer-free pancreata of recipient syngeneic immunocompetent mice. Tumor development in these models is more synchronized, latency is substantially shortened, and tumors develop only in one location, as pre-determined by the choice of a site for cells/tumor fragment implantation.
This technology includes a blood flow imaging method that allows for a higher density of smaller particles to be detected. Current imaging methods that are based on Doppler measurements are limited by the discontinuity in the capillary flow in the space between red blood cells. The core technology is to use a scattering agent to enhance capillary flow or microcirculation. This technology has been tested for optical coherence Doppler tomography, but can be expended to any Doppler based flow imaging techniques such as laser speckle imaging.
This technology includes the creation and use of A3 adenosine receptor (A3AR)-selective agonists for treating chemotherapy-induced peripheral neuropathy, chronic neuropathic pain, rheumatoid arthritis, psoriasis, and other conditions. A3 receptors for adenosine are found in most cells and endogenous activation of the A3 receptors can result in apoptosis, thereby relieving the inflammation or targeting a tumor. A3AR agonists have been a promising strategy for the treatment of various diseases.
Chimeric antigen receptors (CARs) are hybrid proteins consisting of an antibody binding fragment fused to protein signaling domains that cause T-cells which express the CAR to become cytotoxic. Once activated, these cytotoxic T-cells can selectively eliminate the cells which they recognize via the antibody binding fragment of the CAR. By engineering a T-cell to express a CAR that is specific for a certain cell surface protein, it is possible to selectively target those cells for destruction. This is a promising new therapeutic approach known as adoptive cell therapy.
Treatment of B-cell acute lymphoblastic leukemia (ALL) and lymphoma using chimeric antigen receptors (CARs) targeting B-cell surface protein CD19 has demonstrated impressive clinical results in children and young adults. Despite the promising results from CD19 CAR therapy, up to 40% of patients, who initially achieve remission, eventually relapse. Relapse or non-response to CD19-directed CAR therapy may be due to low or diminished CD19 expression. Such patients would be predicted to benefit from CAR therapies targeting other B-cell surface proteins, such as CD22.
HCC is the most frequent malignant tumor in the liver and the third leading cause of cancer death worldwide. A progressive sequence of somatic mutations and epigenetic changes of oncogenes or tumor suppressor genes are believed to cause tumor development. However, high genomic instability in tumors causes the accumulation of genomic aberrations that do not contribute to tumor progression. Therefore, it is important to distinguish between ''driver'' mutations that are functionally important and ''passenger'' mutations that do not provide a selective advantage to the tumor cells.