Some targeted cancer treatments:
a. Cancer cells often overproduce proteins called growth factor receptors, which are found on the cells’ surface and are hence accessible to monoclonal antibodies. Sometimes these growth factor receptors are faulty and overactive.
b. Growth factor receptors trigger the activity of other proteins inside the cell, many of which are kinases that can be blocked with kinase inhibitors.
c. Blood cell cancers (e.g., leukemias and lymphomas) have many proteins on their surface known as CD antigens. Many CD antigens (e.g., CD20, CD38, and CD19) are the targets of antibody-based treatments for blood cancers. Read More
d. Tumors need a blood supply, hence they produce signaling proteins that trigger the growth of blood vessels by a process called angiogenesis. These signaling proteins are blocked by a group of treatments known as the angiogenesis inhibitors.
e. Some cancers are driven by hormones such as estrogen (breast cancer) or testosterone (prostate cancer). The production of these hormones, or their actions, can be blocked using hormone therapies.
f. Some cancers contain fusion proteins. If these fusion proteins are kinases (e.g., Bcr-Abl) they can be blocked with kinase inhibitors.
g. Our cells use proteasomes to recycle old and unwanted proteins. Some cancer cells seem dependent on proteasomes for their survival and can be treated with proteasome inhibitors.
h. Many cancers have difficulty repairing DNA damage; this vulnerability can be exploited with treatments such as PARP inhibitors.
i. Many cancer cells have proteins on their surface such as PD-L1 that directly suppress white blood cells. Cancer cells also persuade other cells in their surroundings to produce the same proteins; hence, they avoid being destroyed by the person’s immune system. Immunotherapies called checkpoint inhibitors can overcome this suppression.
j. Some antibody-based treatments attach to cell surface proteins and deliver chemotherapy or other toxic substances.
k. Cancer cells often contain high levels of proteins such as Bcl-2 that prevent the cell from undergoing apoptosis. Drugs that target Bcl-2 (Bcl-2 inhibitors) proteins can force cancer cells to die.