BAP1 is a tumor suppressor gene, that is often mutated in people with certain kinds of cancer, including both pleural and peritoneal mesothelioma.
In fact, in recent years, scientists have identified what they call a BAP1 cancer syndrome in which individuals with missing or mutated BAP1 genes are more susceptible to mesothelioma, melanoma of eye (uveal melanoma) or skin, and a particular kind of benign intradermal tumor called an MBAIT.
Now, an international team of scientists has released a study indicating that, although BAP1 mutation increases the likelihood of contracting mesothelioma, mesothelioma patients with this anomaly actually have better survival odds than mesothelioma patients without it.
The BAP1 Gene and Mesothelioma Susceptibility
The BRCA1-associated protein 1 (BAP1) gene, located on chromosome 3p21, is responsible for regulating a number of key cellular processes including cellular differentiation, energy production, and death.
Research on families in Cappadocia, Turkey, where mesothelioma is more common than in other parts of the world, has shown that the BAP1 mutation can be passed through the genes from one generation to the next.
In families with this genetic mutation, the risk of contracting mesothelioma, normally an extremely rare cancer, tends to be much higher than would normally be expected.
Mesothelioma Prognosis and BAP1 Mutation
But, as the new international BAP1 study suggests, there may be some good news for mesothelioma patients who have this mutation and for their families. The study conducted by researchers in Italy, Japan, the UK, and the US, involved a detailed analysis of published BAP1 research on a total of 3,447 cancer patients.
Although having a mutated or missing BAP1 gene raised the chances of dying, either from cancer or another cause, among most of the cancer patients studied, in those with mesothelioma, the opposite was true.
“BAP1- significantly increased all-cause mortality, cancer-specific mortality and risk of recurrence in all the tumor types analyzed, except for mesothelioma, in which the presence of BAP1 mutations correlates with a better prognosis,” reports lead author Claudio Luchini of the University and Hospital Trust of Verona. The study also found that mutated BAP1 is more common in women than in men.
At the same time, another recent study conducted in Australia suggests that, because loss of BAP1 expression is very uncommon in certain kinds of abdominal cancers that are similar to mesothelioma, a BAP1 test could be used to help distinguish mesothelioma from one of these other malignancies.
Luchini, C, et al, “Different Prognostic Roles Of Tumor Suppressor Gene BAP1 In Cancer: A Systematic Review With Meta-Analysis”, May 26, 2016, Genes, Chromosomes and Cancer, Epub ahead of print
Andrici, J, et al, “Loss of BAP1 expression is very rare in peritoneal and gynecologic serous adenocarcinomas and can be useful in the differential diagnosis with abdominal mesothelioma”, May 2016, Human Pathology, pp. 9 – 15