Somatic BRCA1-associated protein 1 (BAP1) loss is an early and rare event in esophageal adenocarcinoma

Large-scale and high-resolution mass spectrometry-based proteomics profiling defines molecular subtypes of esophageal cancer for therapeutic targeting

Esophageal cancer (EC) is a type of aggressive cancer without clinically relevant molecular subtypes, hindering the development of effective strategies for treatment. To define molecular subtypes of EC, we perform mass spectrometry-based proteomic and phosphoproteomics profiling of EC tumors and adjacent non-tumor tissues, revealing a catalog of proteins and phosphosites that are dysregulated in ECs. The EC cohort is stratified into two molecular subtypes-S1 and S2-based on proteomic analysis, with the S2 subtype characterized by the upregulation of spliceosomal and ribosomal proteins, and being more aggressive. Moreover, we identify a subtype signature composed of ELOA and SCAF4, and construct a subtype diagnostic and prognostic model. Potential drugs are predicted for treating patients of S2 subtype, and three candidate drugs are validated to inhibit EC. Taken together, our proteomic analysis define molecular subtypes of EC, thus providing a potential therapeutic outlook for improving disease outcomes in patients with EC.

A chalcone inhibits the growth and metastasis of KYSE-4 esophageal cancer cells

Objective

To investigate the in vitro and in vivo anticancer effects of a chalcone against KYSE-4 esophageal cancer cells.

Methods

A chalcone was synthesized via the molecular hybridization strategy based on the anticancer activity of chalcone and dithiocarbamate scaffolds. The anticancer effects of different concentrations of the chalcone derivative were compared in esophageal cancer cells.

Results

This chalcone displayed strong inhibitory effects on esophageal cancer cell growth with an IC₅₀ of 1.06 μM in KYSE-4 cells. Analysis of the mechanism revealed that the derivative obviously inhibited KYSE-4 cell growth, migration, and invasion in a concentration-dependent manner. Furthermore, the compound regulated migration-related biomarkers (E-cadherin, N-cadherin, and Slug) and inhibited the Wnt/β-catenin pathway. According to western blotting, this chalcone suppressed the expression of proline-rich protein 11 (PRR11) in a concentration- and time-dependent manner.

Conclusions

This chalcone might be a leading candidate for suppressing the growth and metastasis of esophageal cancer by downregulating PRR11 expression and inhibiting Wnt/β-catenin signaling.

BAP1 promotes viability and migration of ECA109 cells through KLF5/CyclinD1/FGF-BP1

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.

Family history of cancer and risk of paediatric and young adult's testicular cancer: A Norwegian cohort study

Background

The aim of this study was to examine the association of a family history of cancer with the risk of testicular cancer in young adults.

Methods

This is a prospective cohort study including 1,974,287 males born 1951–2015, of whom 2686 were diagnosed with TC before the age of 30.

Results

A history of TC in male relatives was significantly associated with a diagnosis of TC among children and young adults, including brothers (6.3-fold), sons (4.7-fold), fathers (4.4-fold), paternal uncles (2.0-fold) and maternal uncles (1.9-fold). Individuals with a father diagnosed with a carcinoma or sarcoma showed an elevated risk (1.1-fold and 1.8-fold, respectively). A family history of mesothelioma was positively associated with a risk of TC [(father (2.8-fold), mother (4.6-fold) and maternal uncles and aunt (4.4-fold)]. Elevated risks were also observed when siblings were diagnosed with malignant melanoma (1.4-fold). The risk of TC was also increased when fathers (11.1-fold), paternal (4.9-fold) and maternal uncles and aunts (4.6-fold) were diagnosed with malignant neuroepithelial-tumours.

Conclusion

We found an increased risk of TC among children and young adults with a family history of TC, carcinoma, mesothelioma, sarcoma, malignant melanoma and malignant neuroepithelial tumours. Hereditary cancer syndromes might underlie some of the associations reported in this study.

Immunohistochemical Assessment of BAP1 Protein in Mucoepidermoid Carcinomas

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.

Quantitative Proteomics Identify the Possible Tumor Suppressive Role of Protease-Activated Receptor-4 in Esophageal Squamous Cell Carcinoma Cells

Exposure to carcinogens of tobacco smoke may result in methylation of protease-activated receptors-4 (PAR4) gene and further induces the loss of PAR4 expression, which is considered to be involved in carcinogenesis of esophageal squamous cell carcinoma (ESCC). Here we employed a TMT-based quantitative proteomic approach to identify PAR4-regulated changes of proteomic profiles in ESCC cells and to identify potentially therapeutic value. A total of 33 proteins were found significantly changed with 15 up-regulated and 18 down-regulated in PAR4-activating peptide (PAR4-AP) treated ESCC cells compared with controls. Bioinformatics analysis showed that key higher expressed proteins included those associated with apoptosis and tumor suppressor (e.g. CASP9), and lower expressed proteins included those associated with anti-apoptosis, autophagy and promoting cell proliferation (e.g. CHMP1B, PURA, PARG and HIST1H2AH). Western blot verified changes in five representative proteins including CASP9, CHMP1B, PURA, PARG and HIST1H2AH. Immunohistochemistry analysis showed that CHMP1B, PURA, PARG and HIST1H2AH expression in ESCC tissues were significantly higher than those in adjacent nontumorous tissues. Our findings will be helpful in further investigations into the functions and molecular mechanisms of PAR4 in ESCC.