Improved PE-based Targeted Toxins: A Therapeutic with Increased Effectiveness

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.

Human Monoclonal Antibodies Targeting Glypican-2 in Neuroblastoma

Neuroblastoma is a rare pediatric cancer that affects one in every hundred thousand children under the age of fifteen in the United States. Current standards of care  are chemotherapy and surgery, followed by stem-cell treatments, radiation and anti-ganglioside antibody therapy, which yield an average three-year survival rate of 10-45%. This demonstrates a need for more effective therapies.

High Affinity Nanobodies Targeting B7-H3 (CD276) for Treating Solid Tumors

CD276 (also called B7-H3) is a pan-cancer antigen expressed in multiple solid tumors and an emerging cancer target. CD276 protein is overexpressed in pancreatic cancer, prostate cancer, breast cancer, colon cancer, lung cancer, and brain tumors (such as neuroblastoma) – making it an ideal target for cancer therapy. 

Investigators at the National Cancer Institute (NCI) have isolated a panel of anti-CD276 single domain antibodies (also known as nanobodies) from novel camel and rabbit single domain (VHH) libraries by phage display. 

Chimeric Antigen Receptors (CAR)-T Cells that Target the Non-Shed Portion of Mesothelin as a Therapeutic Agent

Mesothelin (MSLN) is an excellent target for antibody-based therapies of cancer because of its high expression in many malignancies but lack of expression on essential normal tissues. Unfortunately, a large fragment of MSLN is shed from cancer cells, causing the currently available anti-MSLN antibodies (and immunoconjugates thereof) which bind to the shed portion of MSLN to quickly lose their therapeutic effectiveness over time. Indeed, the shed portion of MSLN can act as a decoy for these antibodies, further limiting them from reaching and destroying tumor cells.

Single-domain monoclonal antibodies for the treatment of hepatocellular carcinoma

The National Cancer Institute seeks parties to license human monoclonal antibodies and immunoconjugates and co-develop, evaluate, and/or commercialize large-scale antibody production and hepatocellular carcinoma (HCC) xenograft mouse models. An advantage of these monoclonal antibodies as a potential therapeutic is their specificity, which would reduce deleterious side-effects. HCC is the most common form of liver cancer, and is among the more deadly cancers in the world. There is a need for new treatments that can be successfully applied to a large population of patients.

Monoclonal Antibodies and Immunoconjugates Directed to the Non-ShedPortion (“Stalk”) of Mesothelin are Excellent Candidates for Developing Therapeutic Agents

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.

Antibody and Immunotoxin Treatments for Mesothelin-expressing Cancers

Mesothelin is a cell surface protein that is highly expressed in aggressive cancers such as malignant mesothelioma, ovarian cancer, pancreatic cancer, lung cancer, breast cancer, cholangiocarcinoma, bile duct carcinoma and gastric cancer. As a result, mesothelin is an excellent candidate for tumor targeted immunotherapeutics. However, the antibodies against mesothelin that are available for clinical trials are of murine origin. These antibodies have the potential to elicit immune responses in patients, which may adversely affect the ability to provide patients with repeated doses.

Use of Cucurbitacins and Withanolides for the Treatment of Cancer

Certain members of the cucurbitacin and Withanolide family have been identified that can sensitize some tumor cell lines to cell death (apoptosis) on subsequent exposure of the cells to pro-apoptotic receptor agonists (PARAS) of the TRAIL "death receptors". These PARAS include TRAIL itself, and agonist antibodies to two of its receptors death receptor-4 (DR4 or TRAIL-R1) and death receptor 5 (DR5, TRAIL-R2).