Newly approved breast cancer drug may work for lung cancer

This image shows autophagic vesicles containing
mutant K-Ras formed in the membrane of human
pancreatic cancer cells after exposure to neratinib –
Image courtesy VCU.

CANCER DIGEST – Oct. 14, 2017 – Researchers have found that a recently approved breast cancer drug may block the action of a trio of cancer-causing genes, known as Ras, which are implicated in a number of other cancers, including non-small cell lung cancer.

The drug neratinib was designed to inhibit enzymes produced by two other genes, EGFR and HER2, which make enzymes that regulate cancer cell growth and resistance to chemotherapy.

In a new study published in the journal Oncotarget, researchers, led by Paul Dent, PhD at the Massey Cancer Center of the Virginia Commonwealth University, found that neratinib irreversibly attaches itself to EGFR and HER2, which permanently blocks the function of the cell receptors.

This causes the cell to form fluid-filled sacs called vesicles that degrade the receptors, which inhibits the cancer growth enzymes. However, they also found the vesicles degraded another protein receptor in the cell’s membrane, called c-MET. These vesicles are part of a process known as autophagy, the natural mechanism that breaks down and recycles unneeded cellular components.

If neratinib had that affect of c-MET they asked if it might also block the action of Ras another membrane protein. They tested it on non-small cell lung cancer cells, pancreatic cells and ovarian cancer cells. The results showed neratinib did kill the lung cancer cells that were already resistant to a similar drug called afatinib.

“We are excited about the potential of neratinib to treat a variety of cancers and complement existing therapies,” said Dent in a press release. “We are creating clinical trial concepts and hoping to secure funding to test them. Because neratinib is already approved by the FDA, as is valproic acid, we’re hopeful that we can translate our findings to the clinic relatively quickly once funding is secured.”

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