Comprehensive analysis of the lncRNA-miRNA-mRNA regulatory network for bladder cancer

Multi-omics pan-cancer study of SPTBN2 and its value as a potential therapeutic target in pancreatic cancer

SPTBN2 is a protein-coding gene that is closely related to the development of malignant tumors. However, its prognostic value and biological function in pan-cancer, especially pancreatic cancer (PAAD), have not been reported. In the present study, a novel exploration of the value and potential mechanism of SPTBN2 in PAAD was conducted using multi-omics in the background of pan-cancer. Via various database analysis, up-regulated expression of SPTBN2 was detected in most of the tumor tissues examined. Overexpression of SPTBN2 in PAAD and kidney renal clear cell cancer patients potentially affected overall survival, disease-specific survival, and progression-free interval. In PAAD, SPTBN2 can be used as an independent factor affecting prognosis. Mutations and amplification of SPTBN2 were detected, with abnormal methylation of SPTBN2 affecting its expression and the survival outcome of PAAD patients. Immunoassay results demonstrate that SPTBN2 was a potential biomarker for predicting therapeutic response in PAAD, and may influence the immunotherapy efficacy of PAAD by regulating levels of CD8 + T cells and neutrophil infiltration. Results from an enrichment analysis indicated that SPTBN2 may regulate the development of PAAD via immune pathways. Thus, SPTBN2 is a potential prognostic biomarker and immunotherapy target based on its crucial role in the development of PAAD.

Mirogabalin improves cancer-associated pain but increases the risk of malignancy in mice with pancreatic cancer

ABSTRACT

Mirogabalin, a selective voltage-gated calcium channel α2δ ligand, improves peripheral neuropathic pain; however, its effects on patients with cancers including pancreatic ductal adenocarcinoma (PDAC) remain unknown. We analyzed the effects of mirogabalin on a KPPC ( LSL-KrasG12D/+; Trp53flox/flox; Pdx-1cre/+ ) mouse model of PDAC. Six-week-old KPPC mice received oral mirogabalin (10 mg/kg/day) (n = 10) or vehicle water (n = 14) until the humane end point. Cancer-associated pain was evaluated using the scores of hunching and mouse grimace scale (MGS). Tumor status and plasma cytokine levels were determined using histopathological analysis and cytokine array, respectively. The effects of mirogabalin on the proliferative ability of PDAC cell lines were determined. The scores of the hunching and MGS improved after mirogabalin administration with a decrease in the plasma levels of inflammatory cytokines, such as tumor necrosis factor-α, interleukin-6, and interferon-γ. Although no significant difference in the survival rate was observed, mirogabalin significantly increased pancreatic tumor size and proliferative index of Ki-67 and cyclins. Local arginase-1 + M2-like tumor-associated macrophages and CD31 + tumor blood vessels increased after mirogabalin administration. By contrast, the number of α-smooth muscle actin + cancer-associated fibroblasts, desmoplastic stroma, and CD8 + T cells decreased. Local myeloperoxidase + tumor-associated neutrophils and CD45R + B cells were unaltered. Mirogabalin enhanced the proliferative ability of PDAC cell lines with the upregulation of cyclins and cyclin-dependent kinases; however, it inhibited the potential of pancreatic stellate cells in vitro. Therefore, our results suggest that mirogabalin improves cancer-associated pain but enhances the proliferative potential of PDAC in vitro and in vivo.

Bladder Cancer Progression Is Suppressed Through the Heart and Neural Crest Derivatives Expressed 2-Antisense RNA 1/microRNA-93-5p/Defective in Cullin Neddylation 1 Domain Containing 3 Axis

MicroRNAs (miRNAs) are critical in progression of bladder cancer (BCa). miRNA-93-5p is increased in cancers and is positively correlated with an unfavorable prognosis. But its effects on BCa remain rarely understood. This investigation aimed to dig out miRNA-93-5p affecting biological behaviors of BCa. In this research, mRNA and protein expression in cancer cells were assessed via quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Cell Counting Kit-8 (CCK-8), colony formation, scratch healing, and transwell assays were utilized to analyze cancer cell viability, colony-forming, migration, and invasion, respectively. Bioinformatics analysis predicted upstream regulatory genes and downstream target genes of miRNA-93-5p, with the targeting relationship being verified through a dual-luciferase assay. The BCa xenograft model in nude mice further investigated the effect of miRNA-93-5p and AND2-AS1 on tumor size and quality, and validated the relationship between HAND2-AS1/miRNA-93-5p/DCUN1D3. Our results displayed that miRNA-93-5p was increased in BCa cell lines. Knockdown miRNA-93-5p constrained BCa cell malignant phenotypes. HAND2-AS1 targeted miRNA-93-5p, thus restraining malignant progression of BCa cells. DCUN1D3 was found downstream of miRNA-93-5p. miRNA-93-5p modulated proliferation, migration, and invasion of BCa cells by targeting DCUN1D3. In vivo experiments disclosed that forced expression of lncRNA HAND2-AS1, and inhibited miRNA-93-5p regressed tumor growth. Meanwhile, the same as the results of cell experiments, the expression of miRNA-93-5p was downregulated, and DCUN1D3 expression was advanced in tumor tissues. To conclude, lncRNA HAND2-AS1 exerted anti-tumor effects and regulated BCa cell proliferation, invasion, and migration by targeting miRNA-93-5p/DCUN1D3.

Decreased SPTBN2 expression regulated by the ceRNA network is associated with poor prognosis and immune infiltration in low‑grade glioma

The majority of low-grade gliomas (LGGs) in adults invariably progress to glioblastoma over time. Spectrin β non-erythrocytic 2 (SPTBN2) is detected in numerous tumors and is involved in tumor occurrence and metastasis. However, the specific roles and detailed mechanisms of SPTBN2 in LGG are largely unknown. The present study performed pan-cancer analysis for the expression and prognosis of SPTBN2 in LGG using The Cancer Genome Atlas and The Genotype-Tissue Expression. Western blotting was used to detect the amount of SPTBN2 between glioma tissues and normal brain tissues. Subsequently, based on expression, prognosis, correlation and immune infiltration, non-coding RNAs (ncRNAs) were identified that regulated SPTBN2 expression. Finally, tumor immune infiltrates associated with SPTBN2 and prognosis were performed. Lower expression of SPTBN2 was correlated with an unfavorable outcome in LGG. A significant correlation between the low SPTBN2 mRNA expression and poor clinicopathological features was observed, including wild-type isocitrate dehydrogenase status (P<0.001), 1p/19q non-codeletion (P<0.001) and elders (P=0.019). The western blotting results revealed that, compared with normal brain tissues, the amount of SPTBN2 was significantly lower in LGG tissues (P=0.0266). Higher expression of five microRNAs (miRs/miRNAs), including hsa-miR-15a-5p, hsa-miR-15b-5p, hsa-miR-16-5p, hsa-miR-34c-5p and hsa-miR-424-5p, correlated with poor prognosis by targeting SPTBN2 in LGG. Subsequently, four long ncRNAs (lncRNAs) [ARMCX5-GPRASP2, BASP1-antisense RNA 1 (AS1), EPB41L4A-AS1 and LINC00641] were observed in the regulation of SPTBN2 via five miRNAs. Moreover, the expression of SPTBN2 was significantly correlated with tumor immune infiltration, immune checkpoint expression and biomarkers of immune cells. In conclusion, SPTBN2 was lowly expressed and correlated with an unfavorable prognosis in LGG. A total of six miRNAs and four lncRNAs were identified as being able to modulate SPTBN2 in a lncRNA-miRNA-mRNA network of LGG. Furthermore, the current findings also indicated that SPTBN2 possessed anti-tumor roles by regulating tumor immune infiltration and immune checkpoint expression.

SPTBN2 regulates endometroid ovarian cancer cell proliferation, invasion and migration via ITGB4‑mediated focal adhesion and ECM receptor signalling pathway

Ovarian cancer is as a major contributor to gynaecologic death globally. The present study aimed to investigate the regulatory role of spectrin β non-erythrocytic 2 gene (SPTBN2) in endometroid ovarian cancer and its mechanism of action. According to the Gene Expression Profiling Interactive Analysis (GEPIA) database, SPTBN2 expression is elevated in ovarian cancer tissues and higher SPTBN2 expression indicated a worse prognosis. The present study assessed SPTBN2 mRNA and protein expression levels by reverse transcription-quantitative PCR and western blotting, respectively. Cell viability, proliferation, migration and invasion were assessed with Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine incorporation, wound healing and Transwell assays, respectively. SPTBN2 expression was notably enhanced in ovarian cancer cell lines, especially in A2780 cells compared with HOSEPiC cells (P<0.001). Following transfection with small interfering (si)RNA targeting SPTBN2, the viability, proliferation, migration and invasion of A2780 cells were decreased compared with those of A2780 cells transfected with siRNA-NC (P<0.001). Gene Set Enrichment Analysis database revealed that SPTBN2 was primarily enriched in 'focal adhesion' and 'extracellular matrix (ECM)-receptor interaction', whereas SPTBN2 was significantly associated with integrin β4 (ITGB4) in the GEPIA database. In addition, rescue experiments were performed to determine the mechanism of SPTBN2 in endometroid ovarian cancer. ITGB4 overexpression reversed the inhibitory effects of the SPTBN2 knockdown on viability, proliferation, migration and invasion of A2780 cells (P<0.05). The impacts of SPTBN2 on the expression of focal adhesion and downstream ECM receptor signalling-related proteins, including Src and p-FAK/FAK, were significantly reversed by ITGB4 overexpression (P<0.01). Collectively, SPTBN2 may regulate endometroid ovarian cancer cell proliferation, invasion and migration through the ITGB4-mediated focal adhesion and ECM receptor signalling pathway.

Molecular hallmarks of long non-coding RNAs in aging and its significant effect on aging-associated diseases

Aging is linked to the deterioration of many physical and cognitive abilities and is the leading risk factor for Alzheimer's disease. The growing aging population is a significant healthcare problem globally that researchers must investigate to better understand the underlying aging processes. Advances in microarrays and sequencing techniques have resulted in deeper analyses of diverse essential genomes (e.g., mouse, human, and rat) and their corresponding cell types, their organ-specific transcriptomes, and the tissue involved in aging. Traditional gene controllers such as DNA- and RNA-binding proteins significantly influence such programs, causing the need to sort out long non-coding RNAs, a new class of powerful gene regulatory elements. However, their functional significance in the aging process and senescence has yet to be investigated and identified. Several recent researchers have associated the initiation and development of senescence and aging in mammals with several well-reported and novel long non-coding RNAs. In this review article, we identified and analyzed the evolving functions of long non-coding RNAs in cellular processes, including cellular senescence, aging, and age-related pathogenesis, which are the major hallmarks of long non-coding RNAs in aging.

PRLR and CACNA2D1 Impact the Prognosis of Breast Cancer by Regulating Tumor Immunity

Phosphatase and tensin homolog (PTEN) is one of the highly susceptible genes to breast cancer (BC); however, the role of PTEN-related RNAs in BC remains poorly understood. Understanding the effect of PTEN-related RNAs and their mechanisms may be helpful to clinicians. We screened the differentially expressed RNAs (deRNAs) related to PTEN and established the competitive endogenous RNA (ceRNA) network by integrating several databases. After that, the RNA model, prolactin receptor (PRLR)/calcium voltage-gated channel auxiliary subunit alpha2delta 1 (CACNA2D1), was obtained by KM survival analysis and logistic regression analysis. Finally, mutation, methylation, functional enrichment, and immune correlation were analyzed to explore the roles of these RNAs. Our results showed that PRLR might be harmful to BC, while CACNA2D1 might be beneficial to BC. Furthermore, the abnormal expression of PRLR in BC might result from mutation and hypomethylation, while the aberrant expression of CACNA2D1 might be ascribed to methylation. Mechanistically, PRLR might affect the prognosis of BC by inhibiting the expression of immune checkpoints, while CACNA2D1 might improve the prognosis of BC by increasing the immune cells infiltrating into BC and up-regulating the expression of immune checkpoints. The abnormal expression of PRLR and CACNA2D1 in BC is closely related to the prognosis of BC, and they may serve as targets for the treatment of BC.

Dysregulation of lncRNA–miRNA–mRNA Interactome as a Marker of Metastatic Process in Ovarian Cancer

Ovarian cancer (OC) is one of the most common types of cancer among malignancies of the female reproductive system. This pathology is asymptomatic until advanced stages and has a poor prognosis. Our study aimed to search for lncRNA–miRNA–mRNA competing triplets that promote ovarian tumorigenesis. For this purpose, we analyzed tumor samples from the TCGA database and verified the results experimentally in a set of 46 paired samples of tumor and matched histologically unchanged ovarian tissues from OC patients. The list of RNAs selected in silico for experimental studies included 13 mRNAs, 10 lncRNAs, and 5 miRNAs related to epithelial–mesenchymal transition and angiogenesis. We evaluated the expression of these RNAs by qRT-PCR and assessed the correlation between levels of miRNAs, mRNAs, and lncRNAs. Sixteen significant triplets were revealed, in some of which, e.g., OIP5-AS1–miR-203a–c-MET and OIP5-AS1–miR-203a–ZEB2, both lncRNA and mRNA had sites for miR-203a direct binding. Transfection of the OVCAR-3 and SKOV-3 cell lines with the miR-203a mimic was used to confirm the novel links of miR-203a with ZEB2 and c-MET in OC. These connections suggest that the interactomes have the potential for diagnostics of metastasis at early onset.

Long non-coding RNA MEG8 induced by PLAG1 promotes clear cell renal cell carcinoma through the miR-495-3p/G3BP1 axis

Clear cell renal cell carcinoma (ccRCC) is recognized as one of the most lethal malignancies among the urological system, with constantly increasing mortality. While the molecular mechanisms underlying ccRCC progression are still poorly understood, the molecular and functional role of lncRNA in multiple diseases has been well demonstrated. In this study, we hypothesized that lncRNA MEG8 might participate in ccRCC development. At first, we found that MEG8 expression was increased in ccRCC tumor tissues and cells. Next, we demonstrated that MEG8 knockdown suppressed cell viability, migration, and invasion in vitro and inhibited tumor growth in vivo. Subsequently, we utilized bioinformatics analysis, ChIP, and luciferase assays, and we found that PLAG1 could transcriptionally regulate MEG8 in ccRCC cells. Furthermore, MEG8 promoted G3BP1 expression to aggravate ccRCC tumorigenic properties through sponging miR-495-3p. Our study identified a novel PLAG1/MEG8/miR-495-3p/G3BP1 network in ccRCC development, which might be a promising direction for developing new diagnoses or therapeutic agents for ccRCC.

lncRNA SNHG15 Induced by SOX12 Promotes the Tumorigenic Properties and Chemoresistance in Cervical Cancer via the miR-4735-3p/HIF1a Pathway

Cervical cancer (CC) is one of the most common malignancies in females, with high prevalence and mortality globally. Despite advances in diagnosis and therapeutic strategies developed in recent years, CC is still a major health burden worldwide. The molecular mechanisms underlying the development of CC need to be understood. In this study, we aimed to demonstrate the role of lncRNA SNHG15 in CC progression. Using qRT-PCR, we determined that lncRNA SNHG15 is highly expressed in CC tumor tissues and cells. lncRNA SNHG15 knockdown also reduces the tumorigenic properties of CC in vitro, as determined using the MTT, EdU, flow cytometry, and transwell assays. Using bioinformatics analysis, RNA pull-down, ChIP, and luciferase reporter assays, we verified the molecular mechanisms of lncRNA SNHG15 in CC progression and found that lncRNA SNHG15 expression in CC cells is transcriptionally regulated by SOX12; moreover, lncRNA SNHG15 promotes CC progression via the miR-4735-3p/HIF1a axis. This study can provide a potential target for CC diagnosis or therapeutic strategies in the future.

SPTBN2, a New Biomarker of Lung Adenocarcinoma

Objectives

The roles played by β-III-spectrin, also known as spectrin beta, non-erythrocytic 2 (SPTBN2), in the occurrence and development of lung adenocarcinoma (LUAD) have not been previously examined. Our study aimed to reveal the relationship between the SPTBN2 expression and LUAD.

Materials and Methods

Twenty pairs of LUAD tissues and adjacent tissues were collected from patients diagnosed and treated at the Thoracic Surgery Department of The First Affiliated Hospital of Zhengzhou University from July 2019 to September 2020. RNA sequencing (RNA-seq) analysis determined that the expression of SPTBN2 was higher in LUAD samples than in adjacent normal tissues. The expression levels of SPTBN2 were examined in various databases, including the Cancer Cell Line Encyclopedia (CCLE), Gene Expression Omnibus (GEO), and Human Protein Atlas (HPA). The Search Tool for the Retrieval of Interacting Genes (STRING) online website was used to examine protein–protein interactions involving SPTBN2, and the results were visualized by Cytoscape software. The Molecular Complex Detection (MCODE) plug-in for Cytoscape software was used to identify functional modules of the obtained protein–protein interaction (PPI) network. Gene enrichment analysis was performed, and survival analysis was conducted using the Kaplan–Meier plotter. The online prediction website TargetScan was used to predict SPTBN2-targeted miRNA sequences by searching for SPTBN2 sequences. Finally, we verified the expression of SPTBN2 in the obtained tissue samples using real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). The human lung cancer cell lines A549 and H1299 were selected for the transfection of small interfering RNA (siRNA) targeting SPTBN2 (si-SPTBN2), and the knockdown efficiency was evaluated by RT-qPCR. The cellular proliferation, migration, and invasion capacities of A549 and H1299 cells were determined using the cell counting kit-8 (CCK-8) proliferation assay; the wound-healing assay and the Transwell migration assay; and the Matrigel invasion assay, respectively.

Results

The expression of SPTBN2 in non–small cell lung cancer (NSCLC) ranked 13th among cancer cell lines based on the CCLE database. At the mRNA and protein levels, the expression levels of SPTBN2 were higher in LUAD tissues than in normal lung tissues. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that proteins related to SPTBN2 were enriched in apoptotic and phagosomal pathways. Kaplan–Meier survival analysis revealed that SPTBN2 expression was significantly related to the prognosis of patients with LUAD. The TargetScan database verified that miR-16 was a negative regulator of SPTBN2 mRNA expression. The results of the CCK-8 cell proliferation assay revealed that SPTBN2 knockdown significantly inhibited the cell proliferation abilities of A549 and H1299 cells. The wound-healing assay indicated that SPTBN2 knockdown resulted in reduced migration after 48 h compared with the control group. The Transwell migration and invasion test revealed that the migration and invasion abilities were greatly decreased by SPTBN2 knockdown compared with control conditions.

Conclusion

We uncovered a novel gene, SPTBN2, that was significantly upregulated in LUAD tissues relative to normal tissue expression. SPTBN2 is highly expressed in LUAD, positively correlated with poor prognosis, and can promote the proliferation, migration, and invasion of LUAD cells.

SERPINE2 Overexpression Is Associated with Poor Prognosis of Urothelial Carcinoma

Recent studies have reported that SERPINE2 contributes to the development of various cancers. However, its association with urothelial carcinoma (UC) remains unclear. In this study, data on urinary bladder UC (UBUC) cases from The Cancer Genome Atlas (TCGA) database were used to investigate the prognostic value of SERPINE2 mRNA expression. Then, SERPINE2 expression was analyzed with tissue microarrays constructed from 117 upper tract UC (UTUC) and 84 UBUC tissue specimens using immunohistochemical staining. Results were compared to clinicopathologic data by multivariate analysis. In the TCGA database, high SERPINE2 mRNA expression indicated a poor prognosis in patients with UBUC. Furthermore, Mann-Whitney U test showed that high SERPINE2 immunoexpression was significantly associated with adverse pathologic parameters including invasion, high grade, coexistence of UC in situ, and advanced pT stage (all p < 0.05, except for a marginal association with high-grade UBUC, p = 0.066). Kaplan-Meier analysis revealed that high SERPINE2 expression was associated with worse overall survival (OS; UTUC, p = 0.003; UBUC, p = 0.014) and disease-free survival (UTUC, p = 0.031; UBUC, p = 0.033). Moreover, multivariate analysis identified high SERPINE2 expression as an independent prognostic factor for OS (UTUC, p = 0.002; UBUC, p = 0.024). Taken together, our findings demonstrated that increased SERPINE2 expression is associated with adverse pathologic features and may serve as a prognostic biomarker for UC.

Androgen Receptor Signaling Induces Cisplatin Resistance via Down-Regulating GULP1 Expression in Bladder Cancer

The underlying molecular mechanisms of resistance to cisplatin-based systemic chemotherapy in bladder cancer patients remain to be elucidated, while the link between androgen receptor (AR) activity and chemosensitivity in urothelial cancer has been implicated. Our DNA microarray analysis in control vs. AR knockdown bladder cancer lines identified GULP1 as a potential target of AR signaling. We herein determined the relationship between AR activity and GULP1 expression in bladder cancer cells and then assessed the functional role of GULP1 in cisplatin sensitivity. Androgen treatment in AR-positive cells or AR overexpression in AR-negative cells considerably reduced the levels of GULP1 expression. Chromatin immunoprecipitation further showed direct interaction of AR with the promoter region of GULP1. Meanwhile, GULP1 knockdown sublines were significantly more resistant to cisplatin treatment compared with respective controls. GULP1 knockdown also resulted in a significant decrease in apoptosis, as well as a significant increase in G2/M phases, when treated with cisplatin. In addition, GULP1 was immunoreactive in 74% of muscle-invasive bladder cancers from patients who had subsequently undergone neoadjuvant chemotherapy, including 53% of responders showing moderate (2+)/strong (3+) expression vs. 23% of non-responders showing 2+/3+ expression (P = 0.044). These findings indicate that GULP1 represents a key downstream effector of AR signaling in enhancing sensitivity to cisplatin treatment.