GMXX Subscribers to Business Week on line received the following this morning; expect it to be in the magazine as early as this weekend.
NOVEMBER 11, 2002
Developments to Watch
Edited by Otis Port
Waking Up a Sleeping Anticancer Gene
When cells turn malignant, the immune system can
often spot and kill them before they grow into
tumors. But this sentinel system fails far too often.
Geneticist and immunologist Wilfred A. Jefferies at
the University of British Columbia wanted to know
why. Searching for genes that are turned on and off
in cancer cells, he discovered that a crucial gene is
silenced in more than half of tumors--and in virtually
all metastatic cancers. Its role: making a protein,
dubbed TAP, that performs a key step in moving
characteristic markers called antigens to the
surfaces of cells. Without TAP, there are no cancer markers, so the immune
system fails to spot the rogue cells.
If he added an active version of the gene to tumor cells, Jefferies wondered,
would the immune system then attack the cancer? His experiments in mice
show that the answer is yes. When he used a modified virus to carry the TAP
gene into mice with extensive small-cell lung tumors, 30% of the mice were
cured. The rest showed no metastasis and lived twice as long as those without
the gene.
Before Jefferies can try this approach in humans, the Food & Drug
Administration wants proof it is safe to insert the gene. Jefferies, now chief
science officer of startup GeneMax Corp. (GMXX ) in Blaine, Wash., believes
the company should be able to answer the safety questions and start clinical
trials in melanoma patients within 18 months. In a forthcoming paper, he will
also present data showing that adding the TAP protein can bolster the immune
response to infectious agents such as HIV and smallpox.
By John Carey |
