Researchers from the Harry Perkins Institute of Medical Research have taken an important step towards improved treatment of head and neck cancers with new work that has been published by the journal PLOS ONE.
The researchers, led by Professor Peter Leedman, conducted an in vitro study to explore a potential synergy between a tiny RNA molecule, miR-7, and erlotinib, a drug currently used to treat head and neck cancers.
The two first authors on the study, Felicity Kalinowski and Keith Giles said that although erlotinib was used in the treatment of many cancers, it was often not very effective, with only 20 to 30% of patients deriving much benefit from the drug.
"The responses are typically short and tumours often build up resistance quite quickly when erlotinib is used on its own," explained Ms Kalinowski. "However, when we combined this drug with the anti-cancer microRNA called miR-7, its effectiveness increased."
miR-7 is a microRNA which was identified by Professor Leedman's team to act as a tumour suppressor through inhibition of the epidermal growth factor receptor (EFGR) and its downstream signaling pathways that promote cancer development and progression. MicroRNAs are small RNAs encoded in the genome which act as master regulators to control the expression of sets of genes and entire cellular pathways, and they have potential as a new class of cancer drugs.
"miR-7 seems to offer an advantage over recent EFGR-targeted drugs, like erlotinib," said Dr Giles. "It targets several members of the EFGR pathway, hitting at multiple levels simultaneously, so cancer cells are less likely to survive. Current drugs often block the cancer cells at one level so this approach could be useful to more patients with head and neck cancers."
Head and neck cancer is the sixth most common cancer, with approximately 600,000 new cases globally per annum. The prognosis for many patients with advanced or metastatic cancer is poor.
"We are grateful to the Medical Research Commercialisation Fund which has provided funding for MiReven, a University of Western Australia spin-out company that is aiming to develop miR-7 as a cancer therapy," said the leader of Perkin’s Laboratory for Cancer Medicine, Professor Peter Leedman.
"This research is a vital early step in the process and the support of the Medical Research Commercialisation Fund has enabled pre-clinical experiments that allow us to look forward to new and improved cancer therapies," Professor Leedman said.
"microRNA drugs like miR-7 are offering a new direction for cancer therapeutic interventions," he said. "We have a number of other studies underway and are hopeful that once complete, we will be able to identify a partner to advance miR-7 into clinical development."
Professor Leedman said the results demonstrated the potential for miR-7 to be a useful adjunctive therapy in the treatment of head and neck cancer.