Human basonuclin 2 up-regulates a cascade set of interferon-stimulated genes with anti-cancerous properties in a lung cancer model

N6-methyladenosine facilitates arsenic-induced neoplastic phenotypes of human bronchial epithelial cells by promoting miR-106b-5p maturation

Arsenic is a widespread carcinogen and an important etiological factor for lung cancer. Dysregulated miRNAs have been implicated in arsenic carcinogenesis and the mechanisms of arsenic-induced dysregulated miRNAs have not been fully elucidated. N6-methyladenosine (m6A) modification is known to modulate pri-miRNA processing. However, whether m6A-mediated pri-miRNA processing is involved in arsenic carcinogenesis is poorly understood. Here, we found that m6A modification was significantly increased in arsenite-transformed human bronchial epithelial BEAS-2B cells (0.5 µM arsenite, 16 weeks). Meanwhile, METTL3 was significantly upregulated at week 12 and 16 during cell transformation. The proliferation, migration, invasion, and anchorage-independent growth of arsenite-transformed cells were inhibited by the reduction of m6A levels through METTL3 knockdown. Further experiments suggest that the oncogene miR-106b-5p is a potentially essential m6A target mediating arsenic-induced lung cancer. miR-106b-5p was observed to be upregulated after exposure to arsenite for 12 and 16 weeks, and the reduction of m6A levels caused by METTL3 knockdown inhibited miR-106b-5p maturation in arsenite-transformed cells. What's more, miR-106b-5p overexpression successfully rescued METTL3 knockdown-induced inhibition of the neoplastic phenotypes of transformed cells. Additionally, Basonuclin 2 (BNC2) was uncovered as a potential target of miR-106b-5p and downregulated by METTL3 via enhancing miR-106b-5p maturation. Additionally, the METTL3 inhibitor STM2457 suppressed neoplastic phenotypes of arsenite-transformed BEAS-2B cells by blocking pri-miR-106b methylation. These results demonstrate that m6A modification promotes the neoplastic phenotypes of arsenite-transformed BEAS-2B cells through METTL3/miR-106b-5p/BNC2 pathway, providing a new prospective for understanding arsenic carcinogenesis.

Epigenetic silencing of ZIC4 unveils a potential tumor suppressor role in pediatric choroid plexus carcinoma

Zic family member ZIC4 is a transcription factor that has been shown to be silenced in several cancers. However, understanding the regulation and function of ZIC4 in pediatric choroid plexus tumors (CPTs) remained limited. This study employed data mining and bioinformatics analysis to investigate the DNA methylation status of ZIC4 in CPTs and its correlation with patient survival. Our results unveiled ZIC4 methylation as a segregating factor, dividing CPT cohorts into two clusters, with hyper-methylation linked to adverse prognosis. Hyper-methylation of ZIC4 was confirmed in a choroid plexus carcinoma-derived cell line (CCHE-45) by bisulfite sequencing. Furthermore, our study demonstrated that demethylating agent and a histone methyltransferase inhibitor could reverse ZIC4 silencing. RNA sequencing and proteomic analysis showed that ZIC4 over-expression influenced genes and proteins involved in immune response, antigen processing and presentation, endoplasmic reticulum stress, and metabolism. Functionally, re-expressing ZIC4 negatively impacted cell proliferation and migration. Ultimately, these findings underscore ZIC4 hyper-methylation as a prognostic marker in CPTs and shed light on potential mechanisms underlying its tumor suppressor role in CPC. This insight paves the way for novel therapeutic targets in treating aggressive CPTs.

Hsa_circ_0086414/transducer of ERBB2 (TOB2) axis-driven lipid elimination and tumor suppression in clear cell renal cell cancer via perilipin 3

BACKGROUND

Renal cell cancer (RCC) is characterized by abnormal lipid accumulation. However, the specific mechanism by which such lipid deposition is eliminated remains unclear. Circular RNAs (circRNAs) widely regulate various biological processes, but the effect of circRNAs on lipid metabolism in cancers, especially clear cell renal cell carcinoma (ccRCC), remains poorly understood.

METHODS

The downregulated circRNA, hsa_circ_0086414, was identified from high-throughput RNA-sequencing data of human ccRCC and pair-matched normal tissues. The target relationship between circRNA_0086414 and miR-661, and the transducer of ERBB2 (TOB2) was predicted using publicly available software programs and verified by luciferase reporter assays. The clinical prognostic value of TOB2 was evaluated by bioinformatic analysis. The expression levels of circRNA_0086414, miR-661, TOB2, and perilipin 3 (PLIN3) were measured by quantitative reverse-transcription polymerase chain reaction or western blot analysis. Cell Counting Kit-8, transwell assays, and xenograft models were employed to assess the biological behaviors of the hsa_circ_0086414/TOB2 axis. Oil Red staining and triglyceride assay was conducted to assess lipid deposition.

RESULTS

Herein, we identified a downregulated circRNA, hsa_circ_0086414. Functionally, the restored hsa_circ_0086414 inhibited ccRCC proliferation, metastasis, and lipid accumulation in vitro and in vivo. Furthermore, the downregulated TOB2 predicted adverse prognosis and promoted cancer progression and lipid deposition in ccRCC. Mechanically, the binding of hsa_circ_0086414 to miR-661, as a miRNA sponge, upregulates the expression of TOB2, wielding an anti-oncogene effect. Importantly, the restored hsa_circ_0086414/TOB2 axis significantly contributed to the elimination of lipid deposition by inhibiting the lipid metabolism regulator PLIN3 in ccRCC cells.

CONCLUSIONS

Our data highlight the importance of the hsa_circ_0086414/TOB2/PLIN3 axis as a tumor suppressor and lipid eliminator in ccRCC. The positive modulation of the hsa_circ_0086414/TOB2 axis might lead to the development of novel treatment strategies for ccRCC.

Basonuclin-2 regulates extracellular matrix production and degradation

Epithelial-mesenchymal transition is essential for tissue patterning and organization. It involves both regulation of cell motility and alterations in the composition and organization of the ECM-a complex environment of proteoglycans and fibrous proteins essential for tissue homeostasis, signaling in response to chemical and biomechanical stimuli, and is often dysregulated under conditions such as cancer, fibrosis, and chronic wounds. Here, we demonstrate that basonuclin-2 (BNC2), a mesenchymal-expressed gene, that is, strongly associated with cancer and developmental defects across genome-wide association studies, is a novel regulator of ECM composition and degradation. We find that at endogenous levels, BNC2 controls the expression of specific collagens, matrix metalloproteases, and other matrisomal components in breast cancer cells, and in fibroblasts that are primarily responsible for the production and processing of the ECM within the tumour microenvironment. In so doing, BNC2 modulates the motile and invasive properties of cancers, which likely explains the association of high BNC2 expression with increasing cancer grade and poor patient prognosis.

AC-265347 Inhibits Neuroblastoma Tumor Growth by Induction of Differentiation without Causing Hypocalcemia

Neuroblastoma is the most common extracranial solid tumor of childhood, with heterogeneous clinical manifestations ranging from spontaneous regression to aggressive metastatic disease. The calcium-sensing receptor (CaSR) is a G protein-coupled receptor (GPCR) that senses plasmatic fluctuation in the extracellular concentration of calcium and plays a key role in maintaining calcium homeostasis. We have previously reported that this receptor exhibits tumor suppressor properties in neuroblastoma. The activation of CaSR with cinacalcet, a positive allosteric modulator of CaSR, reduces neuroblastoma tumor growth by promoting differentiation, endoplasmic reticulum (ER) stress and apoptosis. However, cinacalcet treatment results in unmanageable hypocalcemia in patients. Based on the bias signaling shown by calcimimetics, we aimed to identify a new drug that might exert tumor-growth inhibition similar to cinacalcet, without affecting plasma calcium levels. We identified a structurally different calcimimetic, AC-265347, as a promising therapeutic agent for neuroblastoma, since it reduced tumor growth by induction of differentiation, without affecting plasma calcium levels. Microarray analysis suggested biased allosteric modulation of the CaSR signaling by AC-265347 and cinacalcet towards distinct intracellular pathways. No upregulation of genes involved in calcium signaling and ER stress were observed in patient-derived xenografts (PDX) models exposed to AC-265347. Moreover, the most significant upregulated biological pathways promoted by AC-265347 were linked to RHO GTPases signaling. AC-265347 upregulated cancer testis antigens (CTAs), providing new opportunities for CTA-based immunotherapies. Taken together, this study highlights the importance of the biased allosteric modulation when targeting GPCRs in cancer. More importantly, the capacity of AC-265347 to promote differentiation of malignant neuroblastoma cells provides new opportunities, alone or in combination with other drugs, to treat high-risk neuroblastoma patients.

Development of a CAFs-related gene signature to predict survival and drug response in bladder cancer

As one of important components of tumor microenvironment, CAFs (cancer-associated fibroblasts) play a vital role in the development and metastasis of bladder cancer. The present study aimed to develop a CAFs-related gene signature to predict the prognosis of patients and the response to chemotherapy and immunotherapy based on research of multidatabase. Expression data and clinical information were obtained from TCGA and GEO databases. Different bioinformatic and statistical methods were combined to construct the robust CAFs-related gene signature for prognosis. The model was explored from four aspects: single-cell source, immune infiltration, correlation with cancer-related genes and pathways, and prediction of drug response. After screening, five genes (BNC2, LAMA2, MFAP5, NID1, and OLFML1) related to CAFs were used for constructing the signature to divide patients into high- and low-risk groups. Patients in low-risk group had better prognosis and multidatabase analysis confirmed the predictive value. The five genes were mainly expressed by fibroblasts and involved in regulation of pathways related with glycolysis, hypoxia, and epithelial-mesenchymal transition (EMT). BNC2, LAMA2, and NID1 were strongly associated with drug sensitivity. Moreover, the immunological status was different between high- and low-risk groups. High-risk patients had poor response to chemotherapy or immunotherapy. The CAFs-related gene signature might help to optimize risk stratification and provide a new insight in individual treatment for bladder cancer.

Longitudinal proteomic profiling provides insights into host response and proteome dynamics in COVID-19 progression

In managing patients with coronavirus disease 2019 (COVID‐19), early identification of those at high risk and real‐time monitoring of disease progression to severe COVID‐19 is a major challenge. We aimed to identify potential early prognostic protein markers and to expand understanding of proteome dynamics during clinical progression of the disease. We performed in‐depth proteome profiling on 137 sera, longitudinally collected from 25 patients with COVID‐19 (non‐severe patients, n = 13; patients who progressed to severe COVID‐19, n = 12). We identified 11 potential biomarkers, including the novel markers IGLV3‐19 and BNC2, as early potential prognostic indicators of severe COVID‐19. These potential biomarkers are mainly involved in biological processes associated with humoral immune response, interferon signalling, acute phase response, lipid metabolism, and platelet degranulation. We further revealed that the longitudinal changes of 40 proteins persistently increased or decreased as the disease progressed to severe COVID‐19. These 40 potential biomarkers could effectively reflect the clinical progression of the disease. Our findings provide some new insights into host response to SARS‐CoV‐2 infection, which are valuable for understanding of COVID‐19 disease progression. This study also identified potential biomarkers that could be further validated, which may support better predicting and monitoring progression to severe COVID‐19.