File Photo: A maternity nurse takes care of a newborn after bath at the Gansu Provincial Maternity and Child-care Hospital in Lanzhou, capital of northwest China's Gansu Province, Feb. 17, 2016. (Xinhua/Chen Bin)

WASHINGTON, Jan. 17 (Xinhua) -- British scientists found a way to help the immune system fight back against cancer by using a combination of chemotherapy and a kid medicine, shows a study published Wednesday in the journal Clinical Cancer Research.

The advance, reported by scientists in King's College London, used for the first time a combination of chemotherapy and a drug being tested as a treatment for neonatal jaundice, that together help kick-start the body's natural defenses.

The therapy targeted an enzyme called Heme Oxygenase-1 (HO-1), which is active in a variety of cancers. HO-1 can promote the growth of tumors by preventing the immune system from effectively attacking cancer cells.

Scientists have already shown in the laboratory that chemotherapy can trigger immune responses against cancer, but the King's team has found that these responses are suppressed by non-tumor cells called macrophages, which reside in the tumor and produce the HO-1 enzyme.

Researchers found that in preclinical trials, a drug being tested for the treatment of jaundice can effectively prevent the suppression of the immune response stimulated by chemotherapy, allowing the immune system to efficiently attack the cancer.

"The full benefit to patients will be better understood once we move these exciting observations into clinical trials. However, in our preclinical models, when combined with chemotherapy, the efficacy of tumor control was comparable to that of the 'gold-standard' immunotherapy currently being used in the clinic," said James Arnold, an author of the paper.