Another superb example of science reporters doing a terrible job.
Yes, there is some indication that dichloroacetate has some effects on cancer but so far there have been no clinical studies on humans.
An important thing to note: Cancer is not a disease. Cancer is a super-class of a multitude of different diseases. Some cancers are malign, some are benign, some metastasize heavily, some don't. Some can be "cured" with chemotherapy, some with radiation, some not really at all. Some are caused by viruses, some by currently unknown effects. And for the same reason that cancer is not a single disease, there will not be a single cure.
A very thorough overview of the research, and how it got mangled in the reporting process, is given by PZ Myers: Pharyngula Blog: Dichloroacetate and cancer.
The gist:
The simple summary is this: that claim is a lie. There have been no clinical trials of dichloroacetate (DCA) in cancer patients, so there is no basis for claiming they have a cure; some, but not all, cancers might respond in promising ways to the drug, while others are likely to be resistant (cancer is not one disease!); and there are potential neurotoxic side effects, especially when used in conjunction with other chemotherapies.
There is a grain of truth to the allegation that "big pharma" has no interest in it, however.
I can't blame the industry for not following up on this: a clinical trial costs millions of dollars, and even if DCA pans out, there is no profit at all to be gained from it. For this research, we have to turn to public support (they have an interest in better cancer treatments!) and to scientists and doctors themselves, who of course have a great personal interest in seeing their patients get better.