BAP1 mutations inhibit the NF-κB signaling pathway to induce an immunosuppressive microenvironment in uveal melanoma

USP14-Dependent IGF1R Aggravates High Glucose-Induced Diabetic Retinopathy by Upregulating BAP1

Diabetic retinopathy (DR) is a microvascular complication of diabetes. Insulin-like growth factor 1 receptor (IGF1R) has been implicated in the pathogenesis of DR; however, the underlying mechanism remains unclear. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to assess IGF1R mRNA expression. Western blotting assays were performed to analyze the protein expression of IGF1R, ubiquitin-specific peptidase 14 (USP14), and BRCA1-associated protein 1 (BAP1). Cell viability, apoptosis, interleukin-1 beta (IL-1β), and tumor necrosis factor-alpha (TNF-α) levels were analyzed using cell counting kit-8 assay, flow cytometry, and enzyme-linked immunosorbent assays, respectively. Fluorescent microscopy and flow cytometry were performed for reactive oxygen species (ROS) level assessment, and colorimetric assays for iron (Fe2+) and glutathione (GSH) levels. Co-immunoprecipitation assays and/or colocalization techniques were employed to validate the association of IGF1R with USP14 and BAP1. Treatment with high glucose (HG) increased the protein expression of IGF1R, USP14, and BAP1 in ARPE-19 cells. Silencing of IGF1R mitigated HG-induced apoptosis, inflammatory response, and ferroptosis in ARPE-19 cells. USP14 was found to stabilize IGF1R protein expression through deubiquitination. Overexpression of USP14 exacerbated HG-induced cellular injury, whereas silencing of USP14 protected ARPE-19 cells by reducing IGF1R expression. Interaction between IGF1R and BAP1 was confirmed in ARPE-19 cells and IGF1R silencing protected cells from HG-induced injury by regulating BAP1 expression. Thus, USP14-dependent regulation of IGF1R expression and its interaction with BAP1 play a crucial role in the pathogenesis of high glucose-induced diabetic retinopathy.

A Case Report of an Adenomatoid Tumor of the Fallopian Tube: The Histopathologic Challenges and a Review of the Literature

Background: Adenomatoid tumor (AT) is a rare benign neoplasm of mesothelial origin, which mainly occurs in the male and female genital tracts. The most common site for AT occurrence in women is the uterus, which makes the presentation in the fallopian tube(s) a rarity with an incidence of approximately 0.5%. The reported extragenital sites include serosal surfaces, adrenal glands, and visceral organs, are even less common. Macroscopically, ATs present as white-grayish or yellowish irregular yet circumscribed firm nodules, often containing cystic components. Owing to a vast array of histomorphological growth patterns, ATs tend to mimic malignancy and trigger overresection. Such clinical situations have been described by several studies for the ovaries, uterus, and fallopian tubes, underlining the importance of differential diagnosis in order to avoid superfluous treatment. Methods: Herein, we report a presentation of an AT at the oviductal lumen, detected incidentally during prophylactic bilateral salpingo-oophorectomy in a 67-year-old patient with a BRCA1 mutation. Results: Immunohistochemical staining revealed a positive expression for calretinin, WT1, and cytokeratin 7, and negative expression for both PAX8 and CD34, thus confirming the diagnosis of AT and excluding tubal malignancy. Conclusions: This report, with a concise review of the global literature on tubal AT, brings attention to the solitary and asymptomatic nature of the tumor. With a clear diagnosis, no surgical radicality is necessary.

IGSF8 is a potential target for the treatment of gliomas

BACKGROUND

Immunoglobulin superfamily member 8, or IGSF8, is a member of the recently identified immunoglobulin family of proteins. It is mostly produced on cell membranes and has a unique transmembrane structure. It has recently been demonstrated that there is a strong correlation between the expression variation of IGSF8 and the growth of gliomas. Therefore, we used data from the TCGA and CGGA databases to evaluate the function of IGSF8.

METHODS

The TCGA and GTEx data sets' RNA-seq data were utilized to examine IGSF8 expression. The Gene Cards database was utilized to get IGSF8 protein data. The Cluster Profiler data package was used to carry out the IGSF8 enrichment study. The GO and KEGG databases were used to examine the relationship between IGSF8 and cellular physiological and biochemical processes. The TCGA immune cell infiltration scores were obtained from online databases and published studies. Clinical survival data from TCGA and CGGA were used to investigate the predictive significance of IGSF8.

RESULTS

TGGA revealed that the majority of cancers had differential expression of IGSF8. IGSF8 was discovered to be enriched in numerous significant pathways in tumor cells by GO and KEGG. Moreover, a strong correlation was seen between the expression of IGSF8 and the immunomodulatory interactions that occur between non-lymphocytes and lymphocytes. T-cell infiltration, immunological checkpoints, immune-activating and immune-suppressive genes, chemokines, and chemokine receptors were all strongly correlated with IGSF8 expression. Lastly, the TCGA and CGGA databases showed a strong correlation between IGSF8 and the grade and prognosis of gliomas.

CONCLUSION

According to our findings, IGSF8 may be a glioma marker. In order to control the immunological microenvironment, IGSF8 may cooperate with a number of immune checkpoints. This information may be utilized to create novel targeted immunotherapy medications.

Recent Advances in Molecular and Genetic Research on Uveal Melanoma

Uveal melanoma (UM), a distinct subtype of melanoma, presents unique challenges in its clinical management due to its complex molecular landscape and tendency for liver metastasis. This review highlights recent advancements in understanding the molecular pathogenesis, genetic alterations, and immune microenvironment of UM, with a focus on pivotal genes, such as GNAQ/11, BAP1, and CYSLTR2, and delves into the distinctive genetic and chromosomal classifications of UM, emphasizing the role of mutations and chromosomal rearrangements in disease progression and metastatic risk. Novel diagnostic biomarkers, including circulating tumor cells, DNA and extracellular vesicles, are discussed, offering potential non-invasive approaches for early detection and monitoring. It also explores emerging prognostic markers and their implications for patient stratification and personalized treatment strategies. Therapeutic approaches, including histone deacetylase inhibitors, MAPK pathway inhibitors, and emerging trends and concepts like CAR T-cell therapy, are evaluated for their efficacy in UM treatment. This review identifies challenges in UM research, such as the limited treatment options for metastatic UM and the need for improved prognostic tools, and suggests future directions, including the discovery of novel therapeutic targets, immunotherapeutic strategies, and advanced drug delivery systems. The review concludes by emphasizing the importance of continued research and innovation in addressing the unique challenges of UM to improve patient outcomes and develop more effective treatment strategies.

Balanced Epigenetic Regulation of MHC Class I Expression in Tumor Cells by the Histone Ubiquitin Modifiers BAP1 and PCGF1

MHC class I (MHC-I) molecules are critical for CD8+ T cell responses to viral infections and malignant cells, and tumors can downregulate MHC-I expression to promote immune evasion. In this study, using a genome-wide CRISPR screen on a human melanoma cell line, we identified the polycomb repressive complex 1 (PRC1) subunit PCGF1 and the deubiquitinating enzyme BAP1 as opposite regulators of MHC-I transcription. PCGF1 facilitates deposition of ubiquitin at H2AK119 at the MHC-I promoters to silence MHC-I, whereas BAP1 removes this modification to restore MHC-I expression. PCGF1 is widely expressed in tumors and its depletion increased MHC-I expression in multiple tumor lines, including MHC-Ilow tumors. In cells characterized by poor MHC-I expression, PRC1 and PRC2 act in parallel to impinge low transcription. However, PCGF1 depletion was sufficient to increase MHC-I expression and restore T cell-mediated killing of the tumor cells. Taken together, our data provide an additional layer of regulation of MHC-I expression in tumors: epigenetic silencing by PRC1 subunit PCGF1.