BATANG AI, Malaysia (Reuters) - Cancer scientists and backpackers could soon be running into each other in a remote stretch of Borneo jungle that is being turned into one of the world's largest tropical rainforest reserves.

The 2.47 million acre virgin rainforest, straddling Malaysian and Indonesian territory on the huge southeast Asian island of Borneo, is the largest transfrontier reserve in the wet tropics.

The Lanjak Entimau/Bentuang-Karimum Biodiversity Conservation Area -- not the most user-friendly name to tout in tourist brochures -- is home to many newly discovered species of endangered plants and animals, including land crabs, snakes and lizards, local scientists say.

The mountainous, officially protected area is virtually inaccessible and that is the way its protectors would like it to stay. But for the adventurous, and patient, traveler, it represents one of the world's few remaining frontiers.

The easiest way to reach Lanjak Entimau, the Malaysian part of the transfrontier park, is a five-hour bus trip over mostly unpaved roads from the Sarawak capital of Kuching to the Batang Ai Longhouse Resort, managed by Hilton International Co.

From there, Lanjak Entimau is just a 25-minute helicopter ride away, or a four-hour boat journey up river -- or a two-day trek through mostly untracked jungle.

The helicopter lands not far from the hut of a local scientist.

Ecologist Paul Chai has been studying the forest reserve for six months and his discoveries include 1,000 new species of trees.

Knee-deep in the vegetation he was observing, Chai admires a legume vine, the largest vine in the rainforest.

“These vines live in harmony with the trees. They wrap themselves around the cane palms and are very important to the surrounding environment,'' Chai said.

He spends his days laboriously collecting species and discussing their properties with the local Iban tribe.

“The local tribes use these plants for birth control as well as curing cough, kidney disorders, snake bites and infertility. Our findings are proving this to be true. We want to learn as much as we can from them before the older generation passes on,'' Chai told Reuters.

Cancer research has already taken place in the surrounding area of Sarawak, an oil and timber-rich state on the Malaysian part of Borneo.

In 1993, the National Cancer Institute of America approved the compound Costatolide as an interim replacement for Calanolide for preclinical trials. Both substances were collected from two species of Bintangor trees in Sarawak.

Recently, both compounds have been found to be AIDS (acquired immune deficiency syndrome) inhibitors.

Five American and Malaysian collaborating agencies are involved in this research program and the local government hopes their findings will bring several more international prospectors to Lanjak Entimau.

But Barney Chan, manager of the Sarawak Timber Association, said international companies are not leaping at the chance to explore new opportunities.

"We want to present the findings to interested groups, but no one is really coming forward. I don't think people understand the expense of locking up our forests. It's immense,'' Chan said.

Malaysia, the world's largest exporter of tropical hardwoods, has come under fire in recent years by Western environmentalists who accuse it of indiscriminately felling trees in the Borneo rainforests.

To combat the criticism, Malaysia has invested in areas such as Lanjak Entimau by declaring it “protected.''

Meanwhile, Chai and his colleagues dig through the jungle in search of the wonder cures. Their latest test has been on the antibiotic properties of frog skin. The results, Chai happily reports, look positive.

“My results have already convinced me that this area has the potential to be a biodiversity conservation area. We hope to interest others,'' he said.