PHLDA3 promotes lung adenocarcinoma cell proliferation and invasion via activation of the Wnt signaling pathway

Inhibition of PHLDA3 expression in human superoxide dismutase 1-mutant amyotrophic lateral sclerosis astrocytes protects against neurotoxicity

Pleckstrin homology-like domain family A-member 3 (PHLDA3) has recently been identified as a player in adaptive and maladaptive cellular stress pathways. The outcome of pleckstrin homology-like domain family A-member 3 signalling was shown to vary across different cell types and states. It emerges that its expression and protein level are highly increased in amyotrophic lateral sclerosis (ALS) patient-derived astrocytes. Whether it orchestrates a supportive or detrimental function remains unexplored in the context of neurodegenerative pathologies. To directly address the role of pleckstrin homology-like domain family A-member 3 in healthy and ALS astrocytes, we used overexpression and knockdown strategies. We generated cultures of primary mouse astrocytes and also human astrocytes from control and ALS patient-derived induced pluripotent stem cells harbouring the superoxide dismutase 1 mutation. Then, we assessed astrocyte viability and the impact of their secretome on oxidative stress responses in human stem cell-derived cortical and spinal neuronal cultures. Here, we show that PHLDA3 overexpression or knockdown in control astrocytes does not significantly affect astrocyte viability or reactive oxygen species production. However, PHLDA3 knockdown in ALS astrocytes diminishes reactive oxygen species concentrations in their supernatants, indicating that pleckstrin homology-like domain family A-member 3 can facilitate stress responses in cells with altered homeostasis. In support, supernatants of PHLDA3-silenced ALS and even control spinal astrocytes with a lower pleckstrin homology-like domain family A-member 3 protein content could prevent sodium arsenite-induced stress granule formation in spinal neurons. Our findings provide evidence that reducing pleckstrin homology-like domain family A-member 3 levels may transform astrocytes into a more neurosupportive state relevant to targeting non-cell autonomous ALS pathology.

Epigenetic modification of PHLDA2 is associated with tumor microenvironment and unfavorable outcome of immune checkpoint inhibitor-based therapies in clear cell renal cell carcinoma

BACKGROUND

A substantial proportion of patients with metastatic clear cell renal cell carcinoma (ccRCC) cannot derive benefit from immune checkpoint inhibitor (ICI) plus anti-angiogenic agent combination therapy, making identification of predictive biomarkers an urgent need. The members of pleckstrin homology-like domain family A (PHLDA) play critical roles in multiple cancers, whereas their roles in ccRCC remain unknown.

METHODS

Transcriptomic, clinical, genetic alteration and DNA methylation data were obtained for integrated analyses from TCGA database. RNA sequencing was performed on 117 primary tumors and 79 normal kidney tissues from our center. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis, gene set enrichment analysis were performed to explore transcriptomic features. Data from three randomized controlled trials (RCT), including CheckMate025, IMmotion151, JAVELIN101, were obtained for validation.

RESULTS

Members of PHLDA family were dysregulated in pan-cancer. Elevated PHLDA2 expression was associated with adverse clinicopathologic parameters and worse prognosis in ccRCC. Aberrant DNA hypomethylation contributed to up-regulation of PHLDA2. An immunosuppressive microenvironment featured by high infiltrates of Tregs and cancer-associated fibroblasts, was observed in ccRCC with higher PHLDA2 expression. Utilizing data from three RCTs, the association of elevated PHLDA2 expression with poor therapeutic efficacy of ICI plus anti-angiogenic combination therapy was confirmed.

CONCLUSIONS

Our study revealed that elevated PHLDA2 expression regulated by DNA hypomethylation was correlated with poor prognosis and immunosuppressive microenvironment, and highlighted the role of PHLDA2 as a robust biomarker for predicting therapeutic efficacy of ICI plus anti-angiogenic agent combination therapy in ccRCC, which expand the dimension of precision medicine.

Wnt/β-catenin signaling in the development and therapeutic resistance of non-small cell lung cancer

Wnt/β-catenin signaling is a critical pathway that influences development and therapeutic response of non-small cell lung cancer (NSCLC). In recent years, many Wnt regulators, including proteins, miRNAs, lncRNAs, and circRNAs, have been found to promote or inhibit signaling by acting on Wnt proteins, receptors, signal transducers and transcriptional effectors. The identification of these regulators and their underlying molecular mechanisms provides important implications for how to target this pathway therapeutically. In this review, we summarize recent studies of Wnt regulators in the development and therapeutic response of NSCLC.

Temporin-GHaK Exhibits Antineoplastic Activity against Human Lung Adenocarcinoma by Inhibiting the Wnt Signaling Pathway through miRNA-4516

(1) Background: GHaK is derived from the antimicrobial peptide temporin-GHa by substituting the amino acid H with K to enhance its bactericidal activity. The present research aims to broaden the pharmacological potential of GHaK by exploring its antineoplastic activity against human lung adenocarcinoma. (2) Methods: The cell viability, migration, invasion, apoptosis, and cell cycle of A549 and PC-9 cells were tested after GHaK treatment. miRNA sequencing, RT-PCR, Western blotting, and luciferase reporter gene assay were further performed to reveal the potential mechanism. (3) Results: GHaK significantly suppressed cell viability, migration, and invasion; induced apoptosis; and caused cell cycle arrest in the G2/M and S phase in PC-9 and A549 cells, respectively. The miRNA sequencing results show a total of 161 up-regulated and 115 down-regulated miRNAs. Furthermore, the study identified six up-regulated miRNAs (miR-4516, miR-4284, miR-204-5p, miR-12136, miR-4463, and miR-1296-3p) and their inhibitory effects on the expressions of target genes (Wnt 8B, FZD2, DVL3, and FOSL1) caused by miR-4516 directly interacting with Wnt 8B. Western blotting revealed the down-regulation of p-GSK-3β, along with a decreased expressions of cyclin A1 and CDK2 in A549 cells and cyclin B1 and CDK1 in PC-9 cells. (4) Conclusions: Temporin-GHaK exhibits antineoplastic activity against human lung adenocarcinoma by inhibiting the Wnt signaling pathway through miRNA-4516.

Multiomics Analysis of the PHLDA Gene Family in Different Cancers and Their Clinical Prognostic Value

The PHLDA (pleckstrin homology-like domain family) gene family is popularly known as a potential biomarker for cancer identification, and members of the PHLDA family have become considered potentially viable targets for cancer treatments. The PHLDA gene family consists of PHLDA1, PHLDA2, and PHLDA3. The predictive significance of PHLDA genes in cancer remains unclear. To determine the role of pleckstrin as a prognostic biomarker in human cancers, we conducted a systematic multiomics investigation. Through various survival analyses, pleckstrin expression was evaluated, and their predictive significance in human tumors was discovered using a variety of online platforms. By analyzing the protein-protein interactions, we also chose a collection of well-known functional protein partners for pleckstrin. Investigations were also carried out on the relationship between pleckstrins and other cancers regarding mutations and copy number alterations. The cumulative impact of pleckstrin and their associated genes on various cancers, Gene Ontology (GO), and pathway analyses were used for their evaluation. Thus, the expression profiles of PHLDA family members and their prognosis in various cancers may be revealed by this study. During this multiomics analysis, we found that among the PHLDA family, PHLDA1 may be a therapeutic target for several cancers, including kidney, colon, and brain cancer, while PHLDA2 can be a therapeutic target for cancers of the colon, esophagus, and pancreas. Additionally, PHLDA3 may be a useful therapeutic target for ovarian, renal, and gastric cancer.

RELA promotes the progression of oral squamous cell carcinoma via TFAP2A-Wnt/β-catenin signaling

Oral squamous cell carcinoma (OSCC) has emerged as the most prevailing oral malignancy worldwide, characterized by cervical solid lymph node metastasis and strong local invasiveness. Overexpression of Transcription Factor AP-2 alpha (TFAP2A) is observed in a significant proportion of OSCC cases. In this study, we aimed to elucidate the function of TFAP2A in the progression of OSCC and the related molecular signaling pathways. The role of RELA was predicted using bioinformatics analysis. The mRNA abundances of RELA, TFAP2A, and β-catenin were assessed by Western blot and quantitative real-timePCR. The relationship between RELA, TFAP2A, and β-catenin and their correlation with clinicopathological characteristics of OSCC was evaluated. The target of RELA and TFAP2A was identified by the chromatin immunoprecipitation as well as luciferase reporter assay. The colony formation assay and MTS assay were performed to determine the proliferative level of OSCC cells. OSCC cell motility was determined by Transwell assay and wound-healing assay. The protein expressions of epithelial-mesenchymal transition-associated factors were evaluated by Western blot. The expressions of RELA and TFAP2A were elevated in OSCC, and their expressions displayed a positive correlation. The expression levels of RELA and TFAP2A were found to be associated with TNM staging and lymphatic metastasis of OSCC patients. RELA upregulation promoted OSCC progression, as manifested by increased levels of proliferation, invasion, and migration of OSCC cells. We also demonstrated that RELA was directly bound to the promoter of TFAP2A transcription, which activated multiple malignant and metastatic phenotypes. Furthermore, TFAP2A activated the Wnt/β-catenin signaling by targeting the promoter regions of β-catenin. The study found that RELA is critical for promoting the progression of OSCC via the RELA-TFAP2A-Wnt/β-catenin signaling pathway. The RELA-TFAP2A-Wnt/β-catenin signaling pathway is a potential target for reducing the aggressiveness of OSCC.

Wnt signaling pathway-derived score for predicting therapeutic resistance and tumor microenvironment in lung adenocarcinoma

Background: Lung adenocarcinoma (LUAD) is the most common subtype of lung cancer. Due to tumor heterogeneity, understanding the pathological mechanism of tumor progression helps to improve the diagnosis process and clinical treatment strategies of LUAD patients. Methods: The transcriptome pattern, mutant expression and complete clinical information were obtained from the cancer genome atlas (TCGA) database and microarray data from gene expression omnibus (GEO) database. Firstly, we used single sample Gene Set Enrichment Analysis (ssGSEA) to estimate the activation of Wnt signaling pathway in each sample. Consensus clustering algorithm was used to classify LUAD samples into different subgroups according to the transcription patterns of 152 Wnt signaling pathway related genes. Then, ESTIMATE, ssGSEA and Gene Set Variation Analysis (GSVA) algorithms were used to assess the biological pathways and immunocytes infiltration between different subtypes. LASSO-COX algorithm was conducted to construct prognostic model. Kaplan-Meier and multivariate Cox analysis were performed to evaluate the predictive performance of risk model. Gene features were further confirmed using external datasets. Finally, we conducted vitro assay for validating hub gene (LEF1). Results: Based on the transcription patterns of 152 Wnt signaling pathway related genes, four different subtypes of LUAD patients were screened out by consensus clustering algorithm. Subsequently, it was found that patients with cluster A and B had massive immunocytes infiltration, and the survival rate of patients with cluster B was better than that of other subgroups. According to the coefficients in the LASSO- Cox model and the transcriptome patterns of these 18 genes, the risk score was constructed for each sample. The degree of malignancy of LUAD patients with high-risk subgroup was remarkable higher than that of patients with low-risk subgroup (p < 0.001). Subsequently, five top prognostic genes (AXIN1, CTNNB1, LEF1, FZD2, FZD4.) were screened, and their expression values were different between cancer and normal tissues. FZD2 and LEF1 were negatively related to ImmunoScore, and AXIN1 was negatively related to ImmunoScore. The significant correlation between LUAD patient risk score and overall survival (OS) was verified in external datasets. In the A549 cell line, knockdown of LEF1 can reduce the invasive and proliferation ability of LUAD cells. Conclusion: A innovative 18 genes predictive feature based on transcriptome pattern was found in patients with lung adenocarcinoma. These investigations further promote the insight of the prognosis of lung adenocarcinoma and may contribute to disease management at risk stratification.

Prognostic Value, Immune Signature, and Molecular Mechanisms of the PHLDA Family in Pancreatic Adenocarcinoma

Background: Increasing evidence supports the belief that the pleckstrin homology domain family A (PHLDA) family is associated with the development of a variety of cancers. However, the function of the PHLDA family members in PAAD is still unclear. Methods: Comprehensive bioinformatic analyses using R (version 3.6.3), Cytoscape (version 3.9.1), UALCAN, etc., were performed to study the clinicopathological characteristics, prognostic value, immune features, and functional mechanisms of the PHLDA family members in PAAD. Results: The PHLDA family members showed significantly elevated expression in PAAD compared with paracancerous or normal tissues. Their high expression or amplification were significantly correlated with worse clinicopathological characteristics and prognosis in PAAD patients. In addition, the role of the PHLDA family members in the immune regulation is diverse and complex. Mechanistically, TP53 mutations were significantly associated with the promoter methylation and expression levels of the PHLDA family members, which were activated in multiple oncogenic pathways, including the EMT, RAS/MAPK, and TSC/mTOR pathways. Moreover, we found that their expression levels were significantly correlated with the sensitivity of multiple traditional chemotherapeutic drugs and novel targeted MEK1/2 inhibitors. Conclusion: The PHLDA family members play an oncogenic role in the development of PAAD and might serve as new biomarkers or therapeutic targets.

Origin recognition complex subunit 1 (ORC1) augments malignant behaviors of lung adenocarcinoma cells via targeting Wnt signaling

It has been reported that origin recognition complex subunit 1 (ORC1) plays an oncogenic role in certain human cancers. Nevertheless, its regulatory function in lung adenocarcinoma (LUAD) progression was poorly understood. In this study, gene and protein levels were measured via RT-qPCR and Western blotting. LUAD cell viability, apoptosis, and metastasis were determined via CCK-8, TUNEL, and Transwell assays. Bioinformatics analyses were performed using Genotype Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) databases. Herein, it was revealed that ORC1 was evidently upregulated and positively correlated to unsatisfactory prognosis in LUAD. Besides, single-sample gene set enrichment analysis (ssGSEA) revealed that ORC1 is negatively associated with 17 immune infiltrating cells and differently expressed in several kinds of immune cells. Also, Gene Ontology (GO) analysis indicated the involvement of ORC1 in several molecular functions. In addition, in vitro experiments demonstrated that ORC1 facilitated malignant behaviors of LUAD cells; moreover, animal assays further affirmed that ORC1 promoted LUAD tumor growth in vivo. As for the molecular mechanisms involved, it was found that ORC1 depletion inhibited the Wnt pathway in LUAD cells. Furthermore, rescue experiments demonstrated that Wnt signaling activation could abate the impacts of ORC1 knockdown on tumorigenic phenotypes of LUAD cells. In conclusion, our findings demonstrated that ORC1 promoted LUAD progression by regulating the Wnt signaling, indicating ORC1 could be an auspicious biomarker or target for LUAD diagnosis and treatment.