Summary

A new study suggests that sildenafil, the active ingredient in Viagra, may limit cancer spread by disrupting cholesterol use in tumor cells.
Researchers from Israel’s Weizmann Institute and U.S. institutions found sildenafil affects cholesterol trafficking in cancer cells.
Combining sildenafil with statins showed stronger anti-metastatic effects and improved survival for cancer patients, according to health record analyses.
The study highlights a new biological pathway linked to cholesterol regulation and tumor metastasis, but further clinical trials are necessary.
Researchers caution against using sildenafil outside of medical supervision due to potential risks, especially with nitrate medications.

Thekabarnews.com—Sildenafil, the active ingredient in Viagra, may restrict the spread of cancer by disrupting how tumor cells use cholesterol. This finding comes from a new international study.

Researchers from Israel’s Weizmann Institute of Science worked with scientists from the U.S. National Cancer Institute, Clalit Health Services and Rabin Medical Center.

The peer-reviewed journal Cancer Research published their findings online on July 14, 2026.

The team tested sildenafil in mouse cancer models and cultures of cancer cells taken from human patients. Researchers also analyzed 20 years of health data covering approximately five million Clalit members.

The results suggest that sildenafil interferes with cholesterol trafficking inside cancer cells. Cholesterol helps cells maintain their membranes and supplies energy-intensive processes. These processes allow malignant cells to detach from a primary tumor, migrate and invade distant organs.

Sildenafil blocks an enzyme called phosphodiesterase type 5 (PDE5), increasing levels of the signaling molecule cyclic guanosine monophosphate. This molecule is known as cGMP.

The researchers found that cGMP binds to NPC1, a protein that transports cholesterol out of cellular compartments called lysosomes.

This process traps cholesterol inside lysosomes and reduces the amount available to cancer cells. It also disrupts structures involved in cell signaling and energy production. This limits the cells’ ability to migrate and form secondary tumors.

Professor Ayelet Erez of the Weizmann Institute said in an official research report, “We have uncovered a new biological pathway that connects a well-known signaling molecule to cholesterol regulation in cells and shown how this pathway can be used to block cancer cells from forming metastases.”

The study found stronger anti-metastatic effects when researchers combined sildenafil with statins, medicines widely prescribed to lower cholesterol. Sildenafil restricted access to existing cholesterol, while statins reduced the production of new cholesterol.

An analysis of anonymized health records also associated sildenafil use with improved survival among cancer patients.

The data showed an additional dose-dependent benefit among patients who used sildenafil and statins together. This conclusion is according to the study’s published abstract.

The health-record analysis cannot prove that either medicine caused the improved survival. Lifestyle, health status, cancer type, access to treatment and other medications may have influenced the results.

Researchers must now conduct controlled human clinical trials. They need to determine the appropriate dose, identify which cancers may respond and establish whether the treatment safely improves survival.

The study does not support replacing established cancer care or taking sildenafil without medical supervision.

The warning is important because sildenafil can interact dangerously with nitrate medicines and cause a severe drop in blood pressure.

Metastasis remains a major target for cancer research because most cancer deaths result from metastatic disease, according to the U.S. National Cancer Institute.

The World Health Organization (WHO) estimated that cancer caused 9.7 million deaths worldwide in 2022. The findings offer a promising path for repurposing a widely used medicine—but not yet a proven cancer treatment.