Moreover, it appears likely that, in addition to BRCA1 associated protein 1, other yet unknown genetic variants may also influence the individual risk for development of MM, especially after exposure to asbestos and related mineral fibers.
In summary, we found that in MM: (i) multiple minute simultaneous biallelic deletions are frequent in chromosome 3p21, where they occur as distinct events involving multiple genes; (ii) in addition to BAP1, mutations of SETD2, PBRM1, and SMARCC1 are frequent in MM; and (iii) our results suggest that high-density aCGH combined with tNGS provides a more precise estimate of the frequency and types of genes inactivated in human cancer than approaches based exclusively on NGS strategy.
BAP1 loss and high EZH2 expression were highly specific to malignant mesothelioma in differentiating it from benign mesothelial proliferations, and the combination of these two markers improved the diagnostic accuracy.
In the distinction of malignant mesothelioma from benign mesothelial proliferations, immunohistochemical loss of BAP1, the protein expressed by the BAP1 gene, has proven highly specific for malignant mesothelioma.
To evaluate the possible role of BAP1 mutations in the epidemiology of sporadic MM, and their relationship with asbestos exposure, we determined the prevalence of germline BAP1 mutations by the Sanger method in a group of 29 asbestos-exposed patients, 21 of which were diagnosed with MM.
All carriers of inherited heterozygous germline BAP1-inactivating mutations (BAP1<sup>+/-</sup>) developed one and often several BAP1<sup>-/-</sup> malignancies in their lifetime, mostly malignant mesothelioma, uveal melanoma, and so on.
PubMed, Embase and the Cochrane Library and reference lists of related articles were searched, and studies that evaluated the utility of BAP1 in MM were included.
Here we describe a screen of 94 drugs in 15 exome-sequenced MM lines and the discovery of a subset defined by loss of function of the nuclear deubiquitinase BRCA associated protein-1 (BAP1) that demonstrate heightened sensitivity to TRAIL (tumour necrosis factor-related apoptosis-inducing ligand).
We identified BAP1, CDKN2A and NF2 alterations in the cells from MM pleural effusions at a higher frequency than what is typically seen in MM tumours from surgical series.
The present study supports the role of BAP1 as a highly sensitive and specific marker for malignant mesothelioma in serous effusions and argues for inclusion of this test in all specimens in which this diagnosis is considered.
The most frequently altered genes in human MM are cyclin-dependent kinase inhibitor 2A (CDKN2A), which encodes components of the p53 (p14ARF) and RB (p16INK4A) pathways, BRCA1-associated protein 1 (BAP1), and neurofibromatosis 2 (NF2).
Nevertheless, this study strengthens the suspicion that, next to germline BAP1 alterations, other genetic factors might predispose families to the development of MM.
The odds of carrying a mutation in BAP1 (OR, 1,658; 95% CI, 199 to 76,224; P < .001), BRCA2 (OR, 5; 95% CI, 1.0 to 14.7; P = .03), CDKN2A (OR, 53; 95% CI, 6 to 249; P < .001), TMEM127 (OR, 88; 95% CI, 1.7 to 1,105; P = .01), VHL (OR, 51; 95% CI, 1.1 to 453; P = .02), and WT1 (OR, 20; 95% CI, 0.5 to 135; P = .049) were significantly higher in MM cases than in a noncancer control population.
Germline mutations in BAP1 have been associated with BAP1-Tumor Predisposition Syndrome (BAP1-TPDS), a predisposition to multiple tumors within a family that includes uveal melanoma (UM), cutaneous melanoma, malignant mesothelioma and renal cell carcinoma.
While homozygous CKO of <i>Bap1, Cdkn2a</i>, or <i>Nf2</i> alone gave rise to few or no malignant mesotheliomas, inactivation of <i>Bap1</i> cooperated with loss of either <i>Nf2</i> or <i>Cdkn2a</i> to drive development of malignant mesothelioma in approximately 20% of double-CKO mice, and a high incidence (22/26, 85%) of malignant mesotheliomas was observed in <i>Bap1;Nf2;Cdkn2a</i> (triple)-CKO mice.