The Science

Terbinafine

Terbinafine is a drug that has been invented in 1980 by Anton Stütz in Vienna, Austria.
It was developed as antifungal and is one of the gold standard treatment for fungal infections worldwide. During the last 40 years, it has been taken by many millions of patients worldwide. It is a very safe and tolerable drug, and critical side effects are very rare.

Terbinafine is used to treat fungal infections of the skin and nails. It belongs to a class of drugs known as allylamines, which work by inhibiting the enzyme squalene epoxidase (SQLE) in fungi, disrupting the synthesis of ergosterol, which is crucial for maintaining fungal cell membrane integrity and function. Inhibition SQLE in fungal organisms leads to several critical consequences that ultimately result in the death of the fungal cells.

In humans, SQLE is critical in the synthesis pathway of cholesterol, the corresponding molecule to fungal ergosterol, terbinafine binds to SQLE with low affinity and does not affect human cholesterol metabolism. It does not lower cholesterol levels in humans.

During the last 20 years there is increasing evidence suggesting that SQLE plays a critical role in cancer cell metabolism in prostate, colorectal, breast, hepatocellular, squamous cell and other cancers.

Use of terbinafine and risk of death in patients with prostate cancer

A population-based cohort study J. Ji, J.Sundquist, Kr. Sundquist, Intern.J.Cancer, 144, 1888-1895 (2019)
Analysis of 88.272 PC patients 2005-2014 from Swedish Cancer Registry linked to Swedish Prescribed Drug Register
799 PC patients 2005-2014 who received terbinafine
significantly reduced risk of death vs. PC patients who did not receive terbinafine
P 0.002 for PC mortality; low/high cumulative dose 0.05/0.00
p<0.0001 for overall mortality; low/high cumulative dose 0.02/ <0.0001
Systemic use of terbinafine is associated with decreased mortality in PC patients:
47% decrease in PC mortality, 36% decrease in overall mortality

There is an increasing number of publications on squalene epoxidase as a target in oncology, in prostate, colorectal, breast, hepatocellular, squamous cell and other cancers.

Squalene epoxidase as a target in oncology

Squalene epoxidase as a promising metabolic target in cancer treatment. Cancer Letters, 2018

Squalene epoxidase drives NAFLD-induced hepatocellular carcinoma and is a pharmaceutical target. Science 2018

The shape of human squalene epoxidase expands the arsenal against cancer. Nature communications 2019

Squalene epoxidase promotes the proliferation and metastasis of lung squamous cell carcinoma cells. Cancer, 2019

Squalene epoxidase expression is associated with breast tumor progression and a poor prognosis in breast cancer. Oncology Lett. 2021

MiR-205-driven downregulation of cholesterol biosynthesis through squalene epoxidase-inhibition identifies therapeutic vulnerability in aggressive prostate cancer. Nature Commun. 2021

Targeting the key cholesterol biosynthesis enzyme squalene epoxidase for cancer therapy. Front. Oncol., 2022

Squalene epoxidase is a candidate target for treatment of colorectal cancers with p53 mutation and elevated c-myc expression. Int.J.Biol.Sci.2023

P53 and Myc-regulated squalene epoxidase as Achilles heel in colorectal cancer. Int.J.Biol.Sci.2023

Targeting squalene epoxidase confers metabolic vulnerability and overcomes chemoresistance in head and neck squamous cell carcinoma. Advanced Science 2023

Squalene Epoxidase: its regulation and links with cancers. Review. Int.J.Mol.Sci. 2024,3874