More than 40 000 patients worldwide die from esophageal cancer annually. The 5‐year survival rate of patients is only ~ 15–20%, and thus, there is an ongoing need to improve diagnosis and treatment ...of esophageal cancer. Breast cancer type 1 susceptibility protein (BRCA1)‐associated protein (BAP1) is a marker of poor prognosis in several cancers, including uveal melanoma, renal cell carcinoma, cholangiocarcinoma, non‐small cell lung cancer, and colorectal cancer. BAP1 mutations are early and rare events in esophageal carcinoma, but the involvement of BAP1 in progression of esophageal carcinoma is unclear. Here, we report that cell proliferation and migration were significantly enhanced in esophageal carcinoma ECA109 cells overexpressing BAP1, while they were diminished upon BAP1 knockdown. In addition, the expression of Krüppel‐like factor 5 (KLF5), CyclinD1, and FGF‐BP1 was increased by BAP1 overexpression and decreased by BAP1 knockdown. Our data suggest that BAP1 promotes cell proliferation and migration, and enhances the expression of KLF5 and its downstream genes, including CyclinD1 and FGF‐BP1, in the esophageal carcinoma cell line ECA109.
Overexpression of BAP1 in ECA109 results in enhanced cell proliferation and migration and increased expression of Krüppel‐like factor 5 (KLF5) and its downstream genes. Knockdown of BAP1 in ECA109 results in a decrease in cell proliferation and migration, as well as a reduction in the expression of KLF5 and its downstream genes.
Background
Multiple BAP1 negative melanocytic neoplasms are a hallmark of familial cancer susceptibility syndrome caused by BAP1 germline mutation. The syndrome is characterized by increased ...incidence of renal cell carcinoma, mesothelioma, cholangiocarcinoma, cutaneous and uveal melanoma and some other neoplasms.
Methods
We report histomorphologic characteristics of six cutaneous melanocytic neoplasms with loss of BAP1 expression in two members of a family with BAP1‐associated cancer susceptibility syndrome.
Results
The neoplasms were dermal melanocytic nevi characterized by a proliferation of large epithelioid (spitzoid) melanocytes, and adipocytic metaplasia. Nuclear pseudoinclusions and multinucleated melanocytes were present in most neoplasms. In two of the cases, a nodular melanoma was found associated with a dermal nevus. None of the melanomas recurred or metastasized after 6 and 3 years of follow up.
Conclusions
We report two new cases of melanoma arising in a BAP1‐deficient melanocytic nevus in the setting of familial tumor predisposition syndrome. Adipocytic metaplasia and nuclear pseudoinclusions may be additional morphologic clues to a BAP1‐deficient nevus. It remains to be seen whether these features are more common in familial than sporadic lesions.
Uveal melanoma has a very poor prognosis despite successful local primary tumor treatment. In this study, we investigated prognostic factors that more accurately reflected the likelihood ofrecurrence ...and survival and delineated a prognostic model that could effectively identify different risk groups based on initial clinical parameters.
Prognostic factors associated with distant recurrence, recurrence-free survival (RFS), progression-free survival, and overall survival from distant recurrence to death (OS2) were analyzed in 226 patients with stage I-III uveal melanoma who underwent primary local therapy.
Forty-nine patients (21.7%) had distant recurrences, which occurred most frequently in the liver (87.7%). In a multivariate analysis, local radiotherapy improved RFS among patients with multiple recurrence risk factors relative to excision (not reached vs. 19.0 months, p=0.004). Patients with BRCA1-associated protein-1 (BAP1)‒negative primary tumors showed a longer RFS duration after primary treatments, while those with BAP1-negative metastatic tissues had a shorter OS2 compared to those with BAP1-positive tumors, both not statistically insignificance (RFS: not reached vs. 82.0 months, p=0.258; OS2: 15.7 vs. 24.4 months, p=0.216). Male sex (hazard ratio HR, 3.79; p=0.012), a short RFS (HR, 4.89; p=0.014), and a largest metastatic tumor linear diameter ≥ 45 mm (HR, 5.48; p=0.017) were found to correlate with worse post-recurrence survival.
Risk factors could be used to classify uveal melanoma cases and subsequently direct individual treatment strategies. Furthermore, metastasectomy appears to contribute to improved survival outcomes.
Germline mutations in the tumor suppressor gene, BRCA-1 associated protein ( BAP1 ), underlie a tumor predisposition syndrome characterized by increased risk for numerous cancers including uveal ...melanoma, melanocytic tumors and mesothelioma, among others. In the present study we report the identification of a novel germline BAP1 mutation, c.1777C>T, which produces a truncated BAP1 protein product and segregates with cancer. Family members with this mutation demonstrated a primary clinical phenotype of autosomal dominant, early-onset melanocytic neoplasms with immunohistochemistry (IHC) of these tumors demonstrating lack of BAP1 protein expression. In addition, family members harboring the BAP1 c.1777C>T germline mutation developed other neoplastic disease including thyroid cancer. IHC analysis of the thyroid cancer, as well, demonstrated loss of BAP1 protein expression. Our investigation identifies a new BAP1 mutation, further highlights the relevance of BAP1 as a clinically important tumor suppressor gene, and broadens the range of cancers associated with BAP1 inactivation. Further study will be required to understand the full scope of BAP1 -associated neoplastic disease.
With recent advances in immunohistochemical (IHC) techniques, immunohistochemistry now plays a more important role in research, especially in mouse models where characterization of cellular patterns ...of protein expression has become critical. Even with these recent advances, a paucity of IHC quality antibodies for some proteins still exists. To address this, we have developed a novel IHC assay that utilizes a commercially available goat anti-DDDDK peptide polyclonal antibody on paraffin-embedded tissues from knock-in mice expressing proteins of interest tagged with a 3×FLAG epitope at physiologically relevant levels. Focusing on two 3×FLAG-tagged proteins for which specific antibodies were available, USP48 and RIPK3, we were able to validate our anti-DDDDK assay by comparing the IHC directed against the actual proteins to the anti-DDDDK IHC assay, which recognizes the FLAG epitope. We were also able to detect a third 3×FLAG-tagged protein, BAP1, for which quality reagents were not available. This universal IHC method will enable researchers to characterize the expression patterns of proteins of interest when specific antibodies are lacking.
Purpose: The aim of this study was to use massively parallel DNA sequencing to identify GNAQ/11, BAP1 and SF3B1 mutations in ophthalmic melanocytoma. Procedures: Six ophthalmic melanocytoma specimens ...(1 iridociliary and 5 optic nerve) were profiled for genomic alterations in GNAQ/11, BAP1 and SF3B1 using a custom deep sequencing assay. This assay uses solution phase hybridization-based exon capture and deep-coverage massively parallel DNA sequencing to interrogate all protein-coding exons and select introns. Results: The only iridociliary melanocytoma showed a mutation in GNAQ but not in BAP1. Of the 2 optic-nerve melanocytomas that developed into melanoma, one had a GNAQ mutation and both a BAP1 mutation and monosomy 3. The remaining 3 optic-nerve melanocytomas did not reveal mutations in GNAQ/11 or BAP1. SF3B1 mutations were not detected in any specimen. Conclusions: The presence of GNAQ mutation in some iridociliary and optic-nerve melanocytomas suggests a possible relationship between ophthalmic melanocytoma and other ophthalmic melanocytic neoplasms. BAP1 mutation may accompany the transformation of ophthalmic melanocytoma to melanoma.
BAP1 is a gene situated on chromosome 3p in a region that can be modified in renal cell carcinomas (RCCs). Mutations that cause loss of expression of BAP1 frequently occur in primary clear cell renal ...carcinoma (ccRCC). In a previous work, we observed that loss of nuclear BAP1 expression was crucial in ccRCC progression; in the current study, we investigated BAP1 expression in a large series of small conventional ccRCCs treated with partial nephrectomy, to assess a possible role as biomarker and the prognostic value in terms of patients’ survival at long-term follow-up. One hundred sixty-two patients with single pT1 ccRCC were selected from those who underwent surgery at our Institute of Urology between 1987 and 2000. The features considered in this study were gender, age, tumor size, grade, incidence of metastasis, and patient-specific survival; they were correlated with immunohistochemical BAP1 nuclear expression in tumoral tissue. Median follow-up was 197.24 months (range 19 to 274); median survival was 125.34 months (range 5 to 274 months). None of our pT1 ccRCCs showed total loss of nuclear BAP1 staining; we found a significant negative correlation between nuclear BAP1 expression and tumor size and between nuclear BAP1 expression and grade. In small ccRCCs, nuclear BAP1 staining was not correlated with disease-specific 5-year survival.
Our data confirm the established role of BAP1 as a tumor suppressor protein. This is the first report where BAP1 has been studied in pT1 ccRCC tumors, but nuclear BAP1 expression cannot help identify patients having high-risk disease in these patients.
Mucoepidermoid carcinomas are common malignant salivary gland tumors. Despite recent advances in diagnosis and treatment, there has not been much improvement in outcome of these patients, ...necessitating identification of novel targeted therapeutic agents. Genomic profiling of mucoepidermoid carcinomas has recently revealed aberrations in
BAP1
gene. Therefore, we conducted this study to identify BAP1 loss by immunohistochemistry in these tumors. Mucoepidermoid carcinoma cases were retrieved; hematoxylin-and-eosin stained sections were reviewed. Immunohistochemistry for BAP1 was performed. Forty cases were assessed, including 25 salivary gland and 15 pulmonary mucoepidermoid carcinomas. There were 19 cases in the parotid (76%), two in submandibular gland (8%), and remaining 16% from minor salivary gland locations. Ten (40%) were low grade, nine (36%) were intermediate grade, and six (24%) were high grade mucoepidermoid carcinomas. Thirteen (86.7%) pulmonary mucoepidermoid carcinomas were tracheobronchial, while two (13.3%) were intraparenchymal; all were low grade mucoepidermoid carcinomas. On immunohistochemistry, BAP1 nuclear staining was retained in all cases (100%), irrespective of tumor location or grade. Therapeutic connotations necessitate the identification of readily applicable techniques to detect
BAP1
loss in mucoepidermoid carcinomas. Using immunohistochemistry, loss of BAP1 staining was not seen in any of our cases, suggesting insensitivity of BAP1 IHC to detect aberrations at genomic level in these tumors. Analysis of
BAP1
alterations by targeted sequencing may therefore be performed prior to excluding the possibility of response to
BAP1
-targeted therapeutics based on immunohistochemistry alone.
Gene discovery efforts in patients with hematopoietic malignancies have brought to the forefront a series of mutations in genes thought to be involved in the epigenetic regulation of gene ...transcription. These mutations occur in genes known, or suspected, to play a role in modifying cytosine nucleotides on DNA and/or altering the state of histone modifications. Genes such as
ASXL1
,
DNMT3A
,
EZH2
,
IDH1
/
2
,
MLL1
, and
TET2
all have been shown to be mutated and/or translocated in patients with myeloid malignancies. Intriguingly, many of the alterations affecting DNA cytosine modifications in myeloid malignancies (mutations in
DNMT3A
,
IDH1
/
2
, and
TET2
) have also been found in patients with T-cell lymphomas, and
EZH2
mutations appear to be critical in T-cell acute lymphoblastic leukemia development as well. In addition, the discovery of frequent mutations in
CREBBP
,
EP300
,
EZH2
, and
MLL2
in B-cell lymphomas suggests that epigenetic alterations play a critical role in lymphomagenesis. The purpose of this review is to present functional evidence of how alterations in these epigenetic modifiers promote hematopoietic transformation. The conclusions drawn from these data are valuable in understanding biological mechanisms and potential therapeutic targets.
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