While we await an out-and-out cure, major advances are quietly transforming cancer from a swift killer to a chronic condition people live with—many of them happily and normally. As new therapies begin to take shape, the future looks brighter still. Here’s a look at some innovative treatments being studied in cancer therapy.
Made in the laboratory, these protein molecules zero in on specific cancer cells and prompt the immune system to launch an attack. To make them extra destructive, some scientists are pairing them with radioactive molecules, while others are linking monoclonal antibodies with toxins that penetrate cancer cells. The advantage of this therapy is that it doesn’t affect healthy cells. Tositumomab, the latest monoclonal antibody, recently was approved by the FDA for treatment of non-Hodgkins lymphoma.
Just like other bodily tissues and organs, cancerous tumors need a constant blood supply to stay alive. To meet that need, they trick the body into growing a network of tiny blood vessels for their “personal” use, a process called angiogenesis. Preventing that process is the principle behind angiogenesis inhibitors. Angiogenesis inhibitors not only deprive tumors of their blood supply but also keep them from spreading.
Cancer begins when a gene mutates and spawns other defective genes. The goal of gene therapy is to get mutant genes back on track, either by repairing them or by keeping them from replicating. Scientists have found a potent ally in p53—a “tumor-suppressor gene” that detects and disables damaged genes—and are experimenting with ways to deliver p53 to cancerous cells.
Other scientists, meanwhile, are figuring out how to best harness the power of dendritic cells, warrior white blood cells that play a pivotal role in the immune system response. Still others are looking at antisense drugs, man-made DNA that latches onto “bad” genes and scrambles their messages.
The principle behind cancer vaccines is basic: Put the immune system on the defensive by introducing a foreign invader. The problem with cancer cells is that the body thinks they’re friendly, not foreign—that’s why cancer cells are able to spread so easily.
Now scientists have discovered that when they genetically alter antigens (special “marker” proteins on the surface of cancer cells) and reinject them into tumors, the immune system considers them foreign bodies. Result: Disease-fighting T cells launch an attack. Scientists are studying various other approaches to cancer vaccines.