P3H4 is correlated with clinicopathological features and prognosis in bladder cancer

The role of P3H family in cancer: implications for prognosis, tumor microenvironment and drug sensitivity

Introduction

Prolyl 3-hydroxylases (P3H) are crucial enzymes in collagen biosynthesis and are known to be involved in a variety of physiological processes. However, their specific roles in cancer progression, modulation of the tumor microenvironment (TME), and impact on patient prognosis remain areas that require further investigation.

Methods

The investigation involved a comprehensive analysis of expression profiles and clinical data obtained from the Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) databases. This included the assessment of genetic variation, gene expression, and the prognostic significance of P3H family genes. P3H scores were calculated using various databases and R-based tools, followed by correlation analyses with the TME, immune cell infiltration, drug sensitivity and immunotherapy.Variations in P3H gene expression patterns were observed across different tumor types and prognoses, suggesting that most genes within the family were risk factors, especially P3H1 and P3H4. The P3H score was associated with immune infiltration and drug resistance. Notably, individuals with elevated expression of P3H2, P3H3, and CRTAP exhibited higher resistance to multiple anti-tumor drugs.

Results

P3H family proteins play diverse roles in cancer progression, significantly impacting patient prognosis and the effectiveness of immunotherapy.

Conclusions

The P3H score, identified as a potential biomarker for evaluating TME, holds promise in guiding precision medicine strategies.

METTL3 regulates the proliferation, metastasis and EMT progression of bladder cancer through P3H4

Bladder cancer, the most common malignant tumor in the urinary system, exhibits significantly up-regulated expression of P3H4, which is associated with pathological factors. The objective of this study was to elucidate the underlying mechanism of P3H4 in bladder cancer. Initially, we analyzed P3H4 gene expression using the TCGA database and evaluated P3H4 levels in clinical samples and various bladder cell lines. P3H4 was found to be markedly overexpressed in bladder cancer samples. Subsequently, bladder cancer cells were transfected with shRNA targeting P3H4 (sh-P3H4), sh-METTL3, and P3H4 overexpression vectors (P3H4 OE). Viability, migration, and invasion of bladder cancer cells were assessed using CCK-8, wound healing, and transwell assays. Western blot analysis was performed to determine the levels of EMT-associated proteins, while RNA stability assays determined the half-life of P3H4. Knockdown of P3H4 resulted in inhibition of bladder cancer cell proliferation, migration, invasion, and EMT progression. Mechanistically, METTL3 was found to regulate the mRNA stability of P3H4 in bladder cancer. Moreover, overexpression of P3H4 reversed the inhibitory effects of METTL3 knockdown on bladder cancer cell behaviors. Stable cell lines were established by infecting EJ cells with lentiviral vectors containing sh-METTL3 or P3H4 OE. These cells were then implanted into the skin of BALB/c nude mice, and IHC analysis was used to analyze the expression levels of EMT-associated proteins. In vivo studies demonstrated that inhibition of METTL3 suppressed bladder cancer growth and EMT through P3H4. In conclusion, our findings suggest that METTL3 regulates the proliferation, metastasis, and EMT progression of bladder cancer through P3H4, highlighting its potential as a therapeutic target.

CCPG1 recognizes endoplasmic reticulum luminal proteins for selective ER-phagy

The endoplasmic reticulum (ER) is a major cell compartment where protein synthesis, folding, and posttranslational modifications occur with assistance from a wide variety of chaperones and enzymes. Quality control systems selectively eliminate abnormal proteins that accumulate inside the ER due to cellular stresses. ER-phagy, that is, selective autophagy of the ER, is a mechanism that maintains or reestablishes cellular and ER-specific homeostasis through removal of abnormal proteins. However, how ER luminal proteins are recognized by the ER-phagy machinery remains unclear. Here, we applied the aggregation-prone protein, six-repeated islet amyloid polypeptide (6xIAPP), as a model ER-phagy substrate and found that cell cycle progression 1 (CCPG1), which is an ER-phagy receptor, efficiently mediates its degradation via ER-phagy. We also identified prolyl 3-hydroxylase family member 4 (P3H4) as an endogenous cargo of CCPG1-dependent ER-phagy. The ER luminal region of CCPG1 contains several highly conserved regions that we refer to as cargo-interacting regions (CIRs); these interact directly with specific luminal cargos for ER-phagy. Notably, 6xIAPP and P3H4 interact directly with different CIRs. These findings indicate that CCPG1 is a bispecific ER-phagy receptor for ER luminal proteins and the autophagosomal membrane that contributes to the efficient removal of aberrant ER-resident proteins through ER-phagy.

Efficient Delivery of P3H4 siRNA and Chlorin e6 by cRGDfK-Installed Polyarginine Nanoparticles for Tumor-Targeting Therapy of Bladder Cancer

Purpose: Prolyl 3-hydroxylase family member 4 (P3H4) is a potent prognostic oncogene in bladder cancer (BC), and the inhibition of P3H4 suppresses BC tumor growth. This study aimed to evaluate the efficiency of P3H4 inhibition for BC tumor therapy via tumor-targeting nanoparticles. Methods and results: A linear polyarginine peptide (R9) was synthesized, azide-modified, and then assembled with cyclic pentapeptide cRGDfK. Chlorin e6 (ce6)-conjugated CH3-R9-RGD nanoparticles were prepared for the delivery of siP3H4 into T24 cells in vitro and BC tumors in vivo. Dynamic light scattering analysis identified that the optimum CH3-R9-RGD@siP3H4 molar ratio was 30/1. CH3-R9-RGD@ce6/siP3H4 nanocomposites decreased P3H4 expression and cell proliferation and promoted reactive oxygen species production, apoptosis, and calreticulin exposure in T24 cells in vitro. In vivo experiments showed that CH3-R9-RGD@ce6/siP3H4 nanocomposites caused pathological changes, suppressed BC tumor growth, promoted caspase 3 expression, and enhanced calreticulin exposure in tumor cells. Conclusions: The tumor-targeting CH3-R9-RGD nanocomposites encapsulating siP3H4 and ce6 might be an alternative therapeutic strategy or intravesical instillation chemotherapy for BC.

Global analysis of miRNA-mRNA regulation pair in bladder cancer

Purpose

MicroRNA (miRNA) is a class of short non-coding RNA molecules that functions in RNA silencing and post-transcriptional regulation of gene expression. This study aims to identify critical miRNA-mRNA regulation pairs contributing to bladder cancer (BLCA) pathogenesis.

Patients and methods

MiRNA and mRNA microarray and RNA-sequencing datasets were downloaded from gene expression omnibus (GEO) and the cancer genome atlas (TCGA) databases. The tool of GEO2R and R packages were used to screen differential miRNAs (DE-miRNAs) and mRNAs (DE-mRNAs) and DAVID, DIANA, and Hiplot tools were used to perform gene enrichment analysis. The miRNA-mRNA regulation pair were screened from the experimentally validated miRNA-target interactions databases (miRTarbase and TarBase). Twenty-eight pairs of BLCA tissues were used to further verify the screened DE-miRNAs and DE-mRNAs by quantitative reverse transcription and polymerase chain reaction (qRT-PCR). The diagnostic value of the miRNA-mRNA regulation pairs was evaluated by receiver operating characteristic curve (ROC) and decision curve analysis (DCA). The correlation analysis between the selected miRNA-mRNAs regulation pair and clinical, survival and tumor-related phenotypes was performed in this study.

Results

After miRTarBase, the analysis of 2 miRNA datasets, 6 mRNA datasets, and TCGA-BLCA dataset, a total of 13 miRNAs (5 downregulated and 8 upregulated in BLCA tissues) and 181 mRNAs (72 upregulated and 109 downregulated in BLCA tissues) were screened out. The pairs of miR-17-5p (upregulated in BLCA tissues) and TGFBR2 (downregulated in BLCA tissues) were verified in the external validation cohort (28 BLCA vs. 28 NC) using qRT-PCR. Areas under the ROC curve of the miRNA-mRNA regulation pair panel were 0.929 (95% CI: 0.885–0.972, p < 0.0001) in TCGA-BLCA and 0.767 (95% CI: 0.643–0.891, p = 0.001) in the external validation. The DCA also showed that the miRNA-mRNA regulation pairs had an excellent diagnostic performance distinguishing BLCA from normal controls. Correlation analysis showed that miR-17-5p and TGFBR2 correlated with tumor immunity.

Conclusions

The research identified potential miRNA-mRNA regulation pairs, providing a new idea for exploring the genesis and development of BLCA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02538-w.

P3H4 Overexpression Serves as a Prognostic Factor in Lung Adenocarcinoma

Background

The present study is aimed at evaluating the functional and clinical values of P3H4 in lung adenocarcinoma. Moreover, we also investigated the downstream pathways that P3H4 might participate in.

Methods

The differential expression analysis was used to identify genes differentially expressed in lung adenocarcinoma tissues as compared with normal tissues. Survival analysis was used to test the association between P3H4 and survival time. Gene set enrichment analysis was conducted to explore the downstream pathways. CCK8 and transwell were employed to examine the impact of P3H4 on cell phenotypes.

Results

P3H4 was highly upregulated in LUAD tissues at both RNA and protein levels. Moreover, the LUAD patients, who had high expression of P3H4, were also observed to have shorter disease-free survival and overall survival. These results demonstrated that P3H4 could be used as a prognostic biomarker for LUAD. Moreover, we also found that it was the copy number alterations (CNAs), not DNA methylation, that regulated the RNA expression of P3H4, indicating that its upregulation might be partially resulted from the CNAs. Furthermore, functional experiments revealed that the A549 and H1299 cells with siRNA treatment (siP3H4) exhibited significantly decreased cell proliferation after 24 hours, migratory ability, and invasiveness. Functionally, the upregulated proteins in the P3H4 high expression group were mainly enriched in tumor microenvironment-related pathways such as phagosome, focal adhesion, and ECM-receptor interaction and cancer-related pathways such as bladder cancer pathway, proteoglycans in cancer, and hippo signaling pathway.

Conclusion

The present study systematically evaluated the functional and clinical values of P3H4 in LUAD, and explored the related biological pathways. P3H4 might promote LUAD progression through regulating tumor microenvironment-related pathways.

Knockdown of P3H4 inhibits proliferation and invasion of bladder cancer

The prolyl 3-hydroxylase family member 4 (P3H4) (alias SC65) is implicated in a variety of physiological and pathological processes. However, little is known about the role of P3H4 in tumors. This study aimed to investigate the role of P3H4 in bladder cancer (BC) and the regulatory mechanisms that influence its expression. P3H4 was highly expressed in BC tissues. Knockdown of P3H4 inhibited BC cell proliferation, cell cycle, migration and invasion in vitro, and inhibited BC growth in vivo. We also found that ETV4 bound directly to the promoter region of P3H4 and activated its transcription. Furthermore, overexpression of ETV4 rescued the inhibition of proliferation and invasion induced by PH4 silencing. ETV4 was significantly overexpressed in the BC tissues. In conclusion, P3H4 functioned an oncogene role in BC progression, and ETV4 bound directly to the P3H4 promoter region to regulate its transcription.