Ban Zhi Lian (barbed skullcap) was recently found to have anti-cancer activity. This generated a lot of mainstream press - there was even an article in Time magazine about it.
There are in fact many herbs that are used to treat cancer in the Chinese pharmacopeia. In China, besides using the latest radiation and chemotherapy, herbs are used to directly treat cancer. Those herbs generally fall in the traditional Chinese categories of "move blood resolve stasis", "clear heat and relieve toxicity" and possibly "transform phlegm".
Here in the U.S., herbs are generally used to treat the side effects of conventional cancer treatments. Those herbs generally fall into the "tonic" category, meaning herbs that supplement and nourish the body rather than attacking and dispersing. Radiation and chemotherapy are extremely harsh, attacking and draining treatments, so Chinese herbs can be used to counteract the often vicious side effects.
As a side note, the verbs used above are translations of traditional Chinese terms for treatment principles. "Attacking", "draining", "supplementing" and "tonifying" are just a few of many ways that Chinese medicine describes how you can go about treatment. Part of the problem with modern Western medicine is that it is often too much on the attacking and draining side.
Another problem is that biomedical treatments tend to be either too exact or not exact enough. Antibiotics, for instance, kill all bacteria indiscriminately, and therefore significantly weaken the body if taken for long periods of time. I recommend all my patients to take a course of probiotics after taking antibiotics. Then again, some Western medicines get highly specific, blocking certain receptors but not others. I'm thinking here of selective serotonin re-uptake inhibitors (SSRIs) such as Prozac and other depression medications, which can actually increase the likelihood that someone might kill themselves.