The American Society of Clinical Oncology (ASCO) Annual Conference is underway in Orlando this weekend. The Children’s Tumor Foundation hasn’t had a presence at ASCO before because the dates usually conflict with our annual NF Conference, but this year our own meeting is mid June, so we are at ASCO with a booth and attending sessions. Traditionally attracting around 35,000 attendees, the 2009 crowds at ASCO seems sparse according to regulars. ASCO attendees are largely physicians and clinical researchers, and this is reflected in the meeting content, which is focused on the clinical management of tumors and on emerging drug therapies in clinical trials. However Saturday began with a more scientific lean – a review of cell signaling pathways involved in regulating embryonic development, but which are also overactive in many cancers. These pathways – hedgehog, Wnt and notch – are now being investigated as drug target for cancer therapies. A few companies now have hedgehog-targeted drugs as advanced as Phase II clinical trials in both children and adults, and a couple of companies have notch-targeted drugs in trials. It is terrific to see developmental biology leading the way to drug therapies.
As I reported last week from the New York Academy of Sciences meeting, drugs that target and ‘normalize’ tumor blood vessels have shown significant promise as tumor therapies with bevacizumab (Avastin) leading the way (currently in neurofibromatosis trials for NF2). Bevacizumab’s promise seems to be emerging in the clinic as a combination agent to be used with chemotherapy agent temozolomide, surgery or radiation, and may have particular promise in treatment of newly diagnosed tumors. Clinical trialists are still trying to fully understand what bevacizumab can do, and how it works; for example in a small number of patients potential side effects can include impacting wound healing, or cardiovascular events. Of course drug companies are endeavoring to come up with ‘next generation’ bevaczumab to improve action and eliminate side effects.
Many pilot clinical trials in a variety of tumors are combining bevacizumab with other drugs, or combining other drugs in pairs, targeting other cellular pathways: cilengitide targeting integrins; talampanel targeting glutamate receptors; as well as drugs familiar to NF researchers that target Ras pathway elements such as gefitinib, erlotinib, temsirolimus… This is exciting to see, but early stage – many studies include only 3 or 4 patients and as a result some of the findings can be hard to interpret. However one of the great things ASCO does for a subset of posters is to have seasoned scientists review and summarize in a brief talk the highlights from a group of posters on a related topic. This puts findings into a realistic perspective with each other – sometimes exactly what is needed.
More to come!
