Vesnarinone is not a drug that most people would recognize. Originally developed to treat chronic heart failure, it works by regulating the movement of potassium and calcium ions in cardiac muscle cells. However, in a laboratory at the Faculty of Dentistry, Universitas Gadjah Mada (FKG UGM), Prof. drg. Supriatno, M.Kes., MDSc., PhD uncovered a far more unexpected property: the compound was able to kill malignant lymphoma cells that develop in the oral cavity.
The finding was not accidental. It was the result of years of research, published in Current Signal Transduction Therapy in 2020, which explored the molecular mechanisms by which vesnarinone suppresses the growth of oral Burkitt's lymphoma (BL) cells—an aggressive lymphoid malignancy for which effective treatment options remain limited.
Stopping Cancer Cells in Their Tracks
Burkitt's lymphoma is a rapidly growing and highly aggressive B-cell malignancy. Within the oral cavity, the tumor most commonly develops in the maxilla or mandible. It frequently affects children, accounting for nearly 40% of pediatric non-Hodgkin lymphoma cases. In equatorial regions such as Africa and Papua New Guinea, Burkitt's lymphoma represents 50–70% of all childhood malignancies. Despite its aggressive nature, relatively little is known about the molecular biology of oral Burkitt's lymphoma.
In this study, Prof. Supriatno employed Raji cells, a well-established B-lymphocyte cell line widely used as an experimental model for Burkitt's lymphoma. The cells were exposed to varying concentrations of vesnarinone and evaluated using three principal assays: chemotactic migration, caspase-9 activity, and Western blot analysis to examine changes in protein expression.
The results were striking. Raji cells treated with vesnarinone at a concentration of 5.0 × 10⁻² M exhibited a 70.5% reduction in migratory activity compared with untreated controls. In other words, the cancer cells' ability to migrate, spread, and invade surrounding tissues declined dramatically after only 24 hours of treatment.
Two Key Cancer-Promoting Proteins Shut Down
Perhaps the most significant finding emerged at the molecular level. Prof. Supriatno and his colleagues found that vesnarinone suppresses the expression of Skp2 and NF-κB, two proteins known to play critical roles in cancer progression.
Skp2 (S-phase kinase-associated protein 2) normally helps regulate cell-cycle progression by promoting cell division. In many cancers—including lymphoma, colorectal cancer, and lung cancer—Skp2 becomes overexpressed, driving uncontrolled tumor growth. NF-κB, meanwhile, is a central regulator of inflammatory signaling pathways that also promotes cancer cell survival and resistance to apoptosis.
"Vesnarinone suppresses the expression of Skp2 and NF-κB, suggesting that these molecules may serve as promising therapeutic targets for oral Burkitt's lymphoma."
Once these two proteins were inhibited, a cascade of downstream events followed. Expression of p27Kip1, a cell-cycle inhibitor often described as one of the cell's natural "brakes," increased substantially. As p27Kip1 accumulated, cancer cells became unable to continue dividing, ultimately triggering programmed cell death (apoptosis).
Triggering Programmed Cell Death
Apoptosis is fundamentally different from ordinary cell death. Unlike necrosis, which damages surrounding tissues and provokes inflammation, apoptosis is a tightly regulated cellular self-destruction program that allows unwanted or damaged cells to be eliminated without harming neighboring tissues. In this study, apoptosis was assessed by measuring the activity of caspase-9, one of the key enzymes that initiates the apoptotic cascade.
The findings were remarkable. Raji cells treated with vesnarinone at 2.5 × 10⁻² M exhibited a 3.7-fold increase in caspase-9 activity compared with untreated cells. At 5.0 × 10⁻² M, caspase-9 activity increased 7.6-fold. The results clearly demonstrated a dose-dependent response: the higher the concentration of vesnarinone, the greater the number of cancer cells undergoing programmed cell death.
These findings are consistent with previous studies showing that caspase-9 is activated by the Apaf-1 apoptosome complex, which subsequently activates caspase-3 and caspase-7, executing the final stages of apoptosis.
A Long Road Toward Future Cancer Therapy
Vesnarinone has previously been reported to exhibit anticancer activity against several human malignancies, including gastric cancer, lung cancer, hepatocellular carcinoma, acute myeloid leukemia, and salivary gland cancer. Prof. Supriatno's research expands this list by identifying oral Burkitt's lymphoma as another promising therapeutic target.
Nevertheless, translating laboratory discoveries into clinical treatments remains a lengthy process. Experiments performed in cultured cells provide an essential first step but are far from sufficient for immediate clinical application. Before a compound can become an approved therapy, it must undergo preclinical animal studies, followed by multiple phases of clinical trials to establish both safety and efficacy in humans. Even so, this study opens a door that had previously remained largely unexplored. It suggests that Skp2 and NF-κB may represent promising targets for precision therapies aimed at treating oral cancers that have long been difficult to manage.
This is precisely why fundamental laboratory research is so important. Its purpose is not to produce an immediate cure, but to map the biological landscape, understand the disease at its most basic level, and identify vulnerabilities that future therapies can exploit. Vesnarinone may not be the final answer. But it has pointed researchers toward where they should continue looking.
Source DOI: https://doi.org/10.2174/1574362413666180912113856
Authors: Anny Anggraini; drg. Achmad Zam Zam Aghasy, M.Kes.
Photo: Freepik