Cancer researchers are excited by new work that is indicating a cheap, over-the-counter cold remedy (N-Acetyl cysteine, or NAC) can inhibitor the tumour stroma — a cell compartment that is fundamental to the spread of cancer.
Cold remedy
Research published in Seminars in Oncology has confirmed that cancer cells are sustained and strengthened by a protein called MCT4, which feeds them energy, in the form of lactate, from neighbouring cells. Patients, who were administered high dose of NAC, were found to have a dramatic reduction in the levels of MCT4, thereby effectively starving cancer cells as they were less able to feed off the neighbouring cells.
“In cell cultures in the laboratory, we had seen a near complete reduction in MCT4, but to achieve such a substantial result in breast cancer patients is extremely exciting indeed,” said Professor Federica Sotgia, of the Biomedical Research Centre at theUniversity of Salford, UK
The trial, which was conducted by a team including Professor Michael Lisanti, of the University of Salford and US-based Dr Ubaldo Martinez-Outschoorn, included 12 patients who were scheduled for surgery for breast cancer at The Sidney Kimmel Cancer Center (Thomas Jefferson University), in Philadelphia.
These 12 patients were administered with maximum daily doses of NAC for three weeks. Tumour biopsies were taken before and during surgery and key biomarkers (including MCT4 and Ki67) were measured post-surgery. It was found that levels of Ki67 fell by 25% and those of MCT4 fell by approximately 80%.
“High levels of stromal MCT4 are extremely worrying, as they are linked to aggressive cancer behaviour and poor overall survival, so this is very encouraging result,” explained Lisanti. “Our idea was to repurpose an inexpensive FDA-approved drug, to examine if its antioxidant properties could target the feeding behaviour of cancer cells. To be able to inhibit MCT4 protein expression, in a non-toxic way, is huge step forward.”