Stealth Viruses to Kill Cancer


A new tool in cancer treatment is to get cancer cells to kill themselves and other tumor cells.

A huge benefit of this is that healthy cells remain unharmed, sparing patients from the terrible side effects of traditional cancer treatments.

In the newest study, scientists created a technology called SHREAD which stands for shielded retargeted adenovirus. They created SHREAD viruses that specifically target cancer cells.

They engineer these viruses to specifically bind to cancer cells and deliver the information to produce therapeutics. The infected cells then make the therapeutics at much higher levels in the tumor than intravenously delivered drugs can achieve.

In this study the SHREAD viruses carried DNA that could make an approved breast cancer drug, trastuzumab. The engineered viruses were injected into mice with human breast cancer.

Ninety four percent of the time, the viruses infected tumor cells. And those cells began making the drug and killing off tumors. The amount of trastuzumab inside the tumors were 1800 times higher than in mice with tumors that got injections of the drug.

Researchers saw with sophisticated imaging, the SHREAD treatment damaged tumor blood vessels and killed cancer cells all within the tumor itself.

Plus, SHREAD's direct delivery technology overcomes the inefficient process of drug intravenous delivery and reduces side effects. If this option becomes available, it'll not only be more effective but also less expensive.

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