A vitamin E precursor has been found to be effective to reduce tumor volume in breast cancer patients with high levels of human epidermal growth factor receptor (HER2).
Almost 30% of breast cancer patients show high levels of HER2.This is presumed to be the feature that makes the disease stubborn to many treatments including chemotherapy drugs.
Researchers in Griffith University's School of Medical Science have recently shown that pro-vitamin E or alpha-tocopheryl succinate can decrease the tumor volume in experiments done on animals that had high levels of HER2.
Chief investigator Associate Professor Jiri Neuzil said alpha-tocopheryl succinate (alpha-TOS) had the potential to be an inexpensive, safe and selective therapy for hard-to-treat breast cancers.
"Alpha-TOS has already shown promise as a potent anticancer agent in diseases such as colon cancer and mesothelioma. It induces controlled cell death or apoptosis in tumour cells."
Transgenic mice with high HER2 breast cancers were treated over a three week period and tumour size was monitored every three days by ultrasound imaging.
The high resolution ultrasound allows for more accurate measurement of tumour volume than any other non-invasive technique.
The research team found that while alpha-TOS is effective alone, it can be delivered into the tumour cells more efficiently when given in a conjugate form with a targeting peptide.
"Tumour volume reduced more than 50% when animals were treated with the conjugate rather than free alpha-TOS," Associate Professor Neuzil said.
He said one of the benefits of alpha-TOS as a potential anti-cancer drug was that it was metabolised in the liver to vitamin E and unlikely to cause dangerous side effects.
Associate Professor Neuzil is presenting his results at the Gold Coast Health and Medical Research Conference next week. The conference, an initiative of the Griffith Institute of Health and Medical Research, will be held December 14-15, at the Radisson Palm Meadows Resort, Gold Coast.