Tag Archives: cancer cell

Carnitine Promotes Cancer Cell Death, Treats TRAIL-Resistant Cancer

Cancer is often treated by selectively inducing cell death—apoptosis–in tumors. However, many cancers develop resistance to this apoptosis-inducing ligand (TRAIL). Researchers are currently investigating treatments to target the TRAIL-resistant cancer cells. Will the amino acid carnitine (also called L-carnitine) become part of a new therapeutic strategy for fighting cancer?  

Researchers SJ Park, SH Park, et al, with the Graduate School of East-West Medical Science, at Kyung Hee University in South Korea, are exploring the use of carnitine as part of a combination cancer treatment.

TRAIL is a protein which kills cancer cells by causing apoptosis (programmed cell death) in tumor cells. The molecules of the TRAIL protein bind to death receptors in the cancer cells. This has been a promising anti-cancer therapy, particularly because TRAIL has no toxicity to normal cells, unlike, for example, chemotherapy.

However, many cancer cells and primary tumors are resistant to TRAIL, which means the body cannot kill the cancer cells. And some cancer cells, including highly malignant tumors, which were originally sensitive to TRAIL can become resistant after repeated exposure. Can these cancer cells become vulnerable to TRAIL again?

The researchers hoped carnitine would help. Carnitine is biosynthesized in our bodies from the essential amino acids lysine and methionine. Carnitine transports long-chain molecules, and enhances the expression of various proteins, including a protein which induces apoptosis (Bax).

Study shows carnitine makes cancer cells vulnerable, promotes cell death

The researchers tested a combination of carnitine and TRAIL in lung cancer cells, colon carcinoma cells, and breast carcinoma cells. Results showed that carnitine sensitizes TRAIL-resistant cancer cells to TRAIL proteins. The cancer is now vulnerable to the apoptosis-inducing proteins, and the cancer cells are killed.

The study concluded that combining carnitine with TRAIL reverses the resistance of cancer cells. Formulating a combined delivery method of carnitine and TRAIL could become a successful new therapeutic strategy to treat TRAIL-resistant cancer cells.

Sources:

http://www.ncbi.nlm.nih.gov/pubmed/23068102

Can Carnitine Help Prevent Colon Cancer?

A Canadian in vitro study investigated the effects of two nutrients on colon cancer. Would the amino acid carnitine improve the anticancer effect of a fatty acid? Results were promising.

Colon cancer, or colorectal cancer, is one of the most common cancers in the world. The risk of developing colon cancer is about 1 in 20. However, if caught early, the cancer can be cured. The 5-year survival rate for stage 1 (the earliest stage) is almost 75%.

Not all risk factors for developing colon cancer are known, though people with inflammatory bowel disease have an increased risk. People with Type 2 diabetes also have a higher risk of developing colon cancer.

Nutrition and diet are other risk factors. A diet high in red meat and processed meat increases the risk of developing colon cancer. Diets high in vegetables and fiber could reduce the risk, though studies are continually ongoing.

Researchers (M Roy, S Dionne, et al) from the University of Montreal’s Department of Nutrition (Quebec, Canada) developed a study to investigate the effect of diet and colon cancer. The study focused on butyrate and the amino acid carnitine.

Butyrate is a short-chain fatty acid, found in dietary fiber and dairy products. Butyrate has potential anticancer affects. And butyrate’s effectiveness is enhanced by carnitine. Would these two nutrients inhibit colon cancer?

Carnitine and colon cancer cells: results

Human colon cancer cells were incubated with butyrate and carnitine. The colon cancer cells were tested for proliferation–reproducing, and apoptosis—programmed cell death.

The researchers found that butyrate and carnitine acted on the cancer cells at the molecular level. Proteins which cause apoptosis were increased by the butyrate and carnitine, and the cancer cell genetic expression was decreased.

The study concluded that carnitine and butyrate do prevent colon cancer cells from spreading, and also that carnitine and butyrate cause apoptosis in colon cancer cells. This could lead to further in vivo studies, with the hope of finding new treatments for colon cancer

Sources:

http://www.ncbi.nlm.nih.gov/pubmed/19619983