Targeting PIN1 as a Therapeutic Approach for Hepatocellular Carcinoma

Computed tomography-based radiomics predicts the fibroblast-related gene EZH2 expression level and survival of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common subtype of liver cancer. The primary treatment strategies for HCC currently include liver transplantation and surgical resection. However, these methods often yield unsatisfactory outcomes, leading to a poor prognosis for many patients. This underscores the urgent need to identify and evaluate novel therapeutic targets that can improve the prognosis and survival rate of HCC patients.

AIM

To construct a radiomics model that can accurately predict the EZH2 expression in HCC.

METHODS

Gene expression, clinical parameters, HCC-related radiomics, and fibroblast-related genes were acquired from public databases. A gene model was developed, and its clinical efficacy was assessed statistically. Drug sensitivity analysis was conducted with identified hub genes. Radiomics features were extracted and machine learning algorithms were employed to generate a radiomics model related to the hub genes. A nomogram was used to illustrate the prognostic significance of the computed Radscore and the hub genes in the context of HCC patient outcomes.

RESULTS

EZH2 and NRAS were independent predictors for prognosis of HCC and were utilized to construct a predictive gene model. This model demonstrated robust performance in diagnosing HCC and predicted an unfavorable prognosis. A negative correlation was observed between EZH2 expression and drug sensitivity. Elevated EZH2 expression was linked to poorer prognosis, and its diagnostic value in HCC surpassed that of the risk model. A radiomics model, developed using a logistic algorithm, also showed superior efficiency in predicting EZH2 expression. The Radscore was higher in the group with high EZH2 expression. A nomogram was constructed to visually demonstrate the significant roles of the radiomics model and EZH2 expression in predicting the overall survival of HCC patients.

CONCLUSION

EZH2 plays significant roles in diagnosing HCC and therapeutic efficacy. A radiomics model, developed using a logistic algorithm, efficiently predicted EZH2 expression and exhibited strong correlation with HCC prognosis.

Valence-Change MnO2-Coated Arsenene Nanosheets as a Pin1 Inhibitor for Hepatocellular Carcinoma Treatment

The heterogeneity of hepatocellular carcinoma (HCC) can prevent effective treatment, emphasizing the need for more effective therapies. Herein, we employed arsenene nanosheets coated with manganese dioxide and polyethylene glycol (AMPNs) for the degradation of Pin1, which is universally overexpressed in HCC. By employing an "AND gate", AMPNs exhibited responsiveness toward excessive glutathione and hydrogen peroxide within the tumor microenvironment, thereby selectively releasing AsxOy to mitigate potential side effects of As2O3. Notably, AMPNs induced the suppressing Pin1 expression while simultaneously upregulation PD-L1, thereby eliciting a robust antitumor immune response and enhancing the efficacy of anti-PD-1/anti-PD-L1 therapy. The combination of AMPNs and anti-PD-1 synergistically enhanced tumor suppression and effectively induced long-lasting immune memory. This approach did not reveal As2O3-associated toxicity, indicating that arsenene-based nanotherapeutic could be employed to amplify the response rate of anti-PD-1/anti-PD-L1 therapy to improve the clinical outcomes of HCC patients and potentially other solid tumors (e.g., breast cancer) that are refractory to anti-PD-1/anti-PD-L1 therapy.

Recent advances of Pin1 inhibitors as potential anticancer agents

Pin1 (proline isomerase peptidyl-prolyl isomerase NIMA-interacting-1), as a member of PPIase family, catalyzes cis-trans isomerization of pThr/Ser-Pro amide bonds of its substrate proteins, further regulating cell proliferation, division, apoptosis, and transformation. Pin1 is overexpressed in various cancers and is positively correlated with tumor initiation and progression. Pin1 inhibition can effectively reduce tumor growth and cancer stem cell expansion, block metastatic spread, and restore chemosensitivity, suggesting that targeting Pin1 may be an effective strategy for cancer treatment. Considering the promising therapeutic effects of Pin1 inhibitors on cancers, we herein are intended to comprehensively summarize the reported Pin1 inhibitors, mainly highlighting their structures, biological functions and binding modes, in hope of providing a reference for the future drug discovery.

Construction of a T-cell exhaustion-related gene signature for predicting prognosis and immune response in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a heterogeneous malignancy with a rising prevalence worldwide. Immunotherapy has been shown to improve treatment outcomes for HCC. We aimed to construct a T-cell exhaustion-related gene prognostic model (TEXPM) for HCC and to elucidate the immunologic characteristics and advantages of immunotherapy in T-cell exhaustion-Related Gene-defined HCC groups.

METHODS

Single-cell RNA sequencing data were used in conjunction with TCGA Differentially expressed genes (DEGs) to screen for T-cell exhaustion-Related Genes (TEXGs) for subsequent evaluation. Using univariate Cox regression analysis and LASSO regression analysis, five genes (FTL, GZMA, CD14, NPC2, and IER3) were subsequently selected for the construction of a TEXPM. Then, we evaluated the immunologic characteristics and advantages of immunotherapy in groups identified by TEXPM.

RESULTS

The TEXPM was formed with FTL, GZMA, CD14, NPC2, and IER3. The results of the training and validation team studies were consistent, with the low TEXPM group surviving longer than the high TEXPM group (P < 0.001). Multivariate Cox regression analysis demonstrated that TEXPM (HR: 2.347, 95%CI: 1.844-2.987; HR: 2.172, 95% CI: 1.689-2.793) was an independent prognostic variable for HCC patients. The low-TEXPM group was linked to active immunity, less aggressive phenotypes, strong infiltration of CD8+ T cells, CD4 + T cells, and M1 macrophages, and a better response to ICI treatment. A high TEXPM group, on the other hand, was associated with suppressive immunity, more aggressive phenotypes, a significant infiltration of B cells, M0 macrophages, and M2 macrophages, and a reduced response to ICI treatment. FTL is an independent prognostic variable in HCC patients and the knockdown of FTL can affect the biological behavior of hepatocellular carcinoma cells.

CONCLUSIONS

TEXPM is a promising prognostic biomarker connected to the immune system. Differentiating immunological and molecular features and predicting patient outcomes may be facilitated by TEXPM grouping. Furthermore, the expression of FTL was found to be an independent prognostic factor for HCC. Knockdown of FTL significantly inhibited proliferation, migration, and invasive activity in liver cancer cells.

Impact of retrotransposon protein L1 ORF1p expression on oncogenic pathways in hepatocellular carcinoma: the role of cytoplasmic PIN1 upregulation

BACKGROUND

Molecular characterisation of hepatocellular carcinoma (HCC) is central to the development of novel therapeutic strategies for the disease. We have previously demonstrated mutagenic consequences of Long-Interspersed Nuclear Element-1 (LINE1s/L1) retrotransposition. However, the role of L1 in HCC, besides somatic mutagenesis, is not well understood.

METHODS

We analysed L1 expression in the TCGA-HCC RNAseq dataset (n = 372) and explored potential relationships between L1 expression and clinical features. The findings were confirmed by immunohistochemical (IHC) analysis of an independent human HCC cohort (n = 48) and functional mechanisms explored using in vitro and in vivo model systems.

RESULTS

We observed positive associations between L1 and activated TGFβ-signalling, TP53 mutation, alpha-fetoprotein and tumour invasion. IHC confirmed a positive association between pSMAD3, a surrogate for TGFβ-signalling status, and L1 ORF1p (P < 0.0001, n = 32). Experimental modulation of L1 ORF1p levels revealed an influence of L1 ORF1p on key hepatocarcinogenesis-related pathways. Reduction in cell migration and invasive capacity was observed upon L1 ORF1 knockdown, both in vitro and in vivo. In particular, L1 ORF1p increased PIN1 cytoplasmic localisation. Blocking PIN1 activity abrogated L1 ORF1p-induced NF-κB-mediated inflammatory response genes while further activated TGFβ-signalling confirming differential alteration of PIN1 activity in cellular compartments by L1 ORF1p.

DISCUSSION

Our data demonstrate a causal link between L1 ORF1p and key oncogenic pathways mediated by PIN1, presenting a novel therapeutic avenue.

Novel pH-sensitive nanoparticles based on prodrug strategy to delivery All-Trans Retinoic Acid for breast cancer

Developing chemotherapy with nanoparticle-based prodrugs provides promising strategies for improving the safety and delivery of anti-cancer drugs therapeutics and effective cancer treatment. Herein, we developed a pH-sensitive prodrug delivery system (All-Trans-Retinoic Acid (ATRA) grafted poly (β-amino esters) (PBAE) copolymers, ATRA-g-PBAE) for delivery of ATRA with some physicochemical and biological properties. The in vitro release of ATRA-g-PBAE prodrug nanoparticles (PNPs) was sustained-release and pH-sensitive. The cytotoxicity and uptake of different preparations in vitro were evaluated on MCF-7 cells at pH 7.4 and 5.5. The carrier PBAE had no cytotoxicity, and ATRA-g-PBAE PNPs could significantly inhibit cell growth at pH 5.5. MCF-7 cells treated with Cy5.5 grafted PBAE (Cy5.5-PBAE) showed stronger fluorescence signals at pH 5.5. Meanwhile, ATRA-g-PBAE PNPs entered the cell via a clathrin-mediated endocytic pathway. Subsequently, PBAE protonation facilitated the escape of PNPs from the lysosome and released the drug. ATRA-g-PBAE seems promising as a novel pH-sensitive prodrug to overcome the limitations of ATRA for breast cancer therapy.

Roles of peptidyl prolyl isomerase Pin1 in viral propagation

Peptidyl-prolyl isomerase (PPIase) is a unique enzyme that promotes cis-trans isomerization of a proline residue of a target protein. Peptidyl-prolyl cis-trans isomerase NIMA (never in mitosis A)-interacting 1 (Pin1) is a PPIase that binds to the pSer/pThr-Pro motif of target proteins and isomerizes their prolines. Pin1 has been reported to be involved in cancer development, obesity, aging, and Alzheimer's disease and has been shown to promote the growth of several viruses including SARS-CoV-2. Pin1 enhances the efficiency of viral infection by promoting uncoating and integration of the human immunodeficiency virus. It has also been shown that Pin1 interacts with hepatitis B virus proteins and participates in viral replication. Furthermore, Pin1 promotes not only viral proliferation but also the progression of virus-induced tumorigenesis. In this review, we focus on the effects of Pin1 on the proliferation of various viruses and discuss the underlying molecular mechanisms.

The role of peptidyl-prolyl isomerase Pin1 in neuronal signaling in epilepsy

Epilepsy is a common symptom of many neurological disorders and can lead to neuronal damage that plays a major role in seizure-related disability. The peptidyl-prolyl isomerase Pin1 has wide-ranging influences on the occurrence and development of neurological diseases. It has also been suggested that Pin1 acts on epileptic inhibition, and the molecular mechanism has recently been reported. In this review, we primarily focus on research concerning the mechanisms and functions of Pin1 in neurons. In addition, we highlight the significance and potential applications of Pin1 in neuronal diseases, especially epilepsy. We also discuss the molecular mechanisms by which Pin1 controls synapses, ion channels and neuronal signaling pathways to modulate epileptic susceptibility. Since neurotransmitters and some neuronal signaling pathways, such as Notch1 and PI3K/Akt, are vital to the nervous system, the role of Pin1 in epilepsy is discussed in the context of the CaMKII-AMPA receptor axis, PSD-95-NMDA receptor axis, NL2/gephyrin-GABA receptor signaling, and Notch1 and PI3K/Akt pathways. The effect of Pin1 on the progression of epilepsy in animal models is discussed as well. This information will lead to a better understanding of Pin1 signaling pathways in epilepsy and may facilitate development of new therapeutic strategies.

The kingdom of the prolyl-isomerase Pin1: The structural and functional convergence and divergence of Pin1

More than 20 years since its discovery, our understanding of Pin1 function in various diseases continues to improve. Pin1 plays a crucial role in pathogenesis and has been implicated in metabolic disorders, cardiovascular diseases, inflammatory diseases, viral infection, cancer and neurodegenerative diseases such as Alzheimer’s, Parkinson’s and Huntington’s disease. In particular, the role of Pin1 in neurodegenerative diseases and cancer has been extensively studied. Our understanding of Pin1 in cancer also led to the development of cancer therapeutic drugs targeting Pin1, with some currently in clinical trial phases. However, identifying a Pin1-specific drug with good cancer therapeutic effect remains elusive, thus leading to the continued efforts in Pin1 research. The importance of Pin1 is highlighted by the presence of Pin1 orthologs across various species: from vertebrates to invertebrates and Kingdom Animalia to Plantae. Among these Pin1 orthologs, their sequence and structural similarity demonstrate the presence of conservation. Moreover, their similar functionality between species further highlights the conservancy of Pin1. As researchers continue to unlock the mysteries of Pin1 in various diseases, using different Pin1 models might shed light on how to better target Pin1 for disease therapeutics. This review aims to highlight the various Pin1 orthologs in numerous species and their divergent functional roles. We will examine their sequence and structural similarities and discuss their functional similarities and uniqueness to demonstrate the interconnectivity of Pin1 orthologs in multiple diseases.

Antitumor Effect of Pseudolaric Acid B Involving Regulation of Notch1/Akt Signaling Response in Human Hepatoma Cell In Vitro

Background

Liver cancer, particularly hepatocellular carcinoma (HCC), is the fourth leading cause of cancer-related death worldwide. Sorafenib is a crucial drug for the treatment of advanced HCC, but it is difficult to meet the challenge of increasing clinical demands due to its severe side effects and drug resistance. Hence, development of novel antitumor drugs is urged. Previous studies showed that pseudolaric acid B (PAB) could reduce the expression of protein kinase B (PKB/Akt), a downstream effector of Notch signaling, facilitating cell apoptosis in HCC. The disruption of Notch signaling was verified to exacerbate malignant progression and drug resistance, however, the antitumor effect of PAB on Notch signaling in HCC remains unclear. Thus, this study aims to investigate the anti-HCC effect of PAB in association with the regulation of Notch1/Akt signaling.

Methods

CCK-8 assay and transwell assay were used to examine the cell proliferation and invasion in Huh7 cells after treatment with PAB and a Notch inhibitor DAPT. Moreover, the cell cycle of Huh7 cells after treatment with PAB was analyzed using flow cytometry. Finally, the changes of Notch1, Jagged1, Hes1, and Akt expression at the protein and mRNA level in Notch1/Akt signaling in Huh7 cells after treatment with PAB and DAPT were analyzed using immunofluorescence assay and real-time qPCR.

Results

The proliferation rate of Huh7 cells exposed to PAB of 0.5, 1, 2, 4, 8, 10, 20, 40, 80, 100, and 200 μmol/L revealed a time-and dose-dependent decrease in vitro, showing cell cycle arrest at G2/M phase (P < 0.05). Furthermore, compared with the untreated group, at the concentration of 40 μmol/L, the proliferation rate and invasion rate of Huh7 cells in PAB, DAPT, and PAB-DAPT combination (PAB + DAPT) group were significantly decreased (P < 0.05), but the PAB + DAPT showed no synergistic antiproliferation and anti-invasion effect in comparison with PAB treatment alone (P > 0.05). In addition, compared with the untreated group, PAB and DAPT alone significantly downregulated the expression of Notch1, Jagged1, Hes1, Akt mRNA, or/and protein in Huh7 cells (P < 0.05), but there was no significant difference in synergistic downregulated effect between the PAB + DAPT group and the PAB group (P > 0.05).

Conclusion

PAB can suppress proliferation and invasion of HCC cells through downregulating the expression of Notch1/Akt signaling protein and mRNA, and may be a potential novel antitumor drug candidate for the clinical treatment of HCC in the future.

Construction of a Ferroptosis-Related Nine-lncRNA Signature for Predicting Prognosis and Immune Response in Hepatocellular Carcinoma

Ferroptosis is an iron-dependent cell death process that plays important regulatory roles in the occurrence and development of cancers, including hepatocellular carcinoma (HCC). Moreover, the molecular events surrounding aberrantly expressed long non-coding RNAs (lncRNAs) that drive HCC initiation and progression have attracted increasing attention. However, research on ferroptosis-related lncRNA prognostic signature in patients with HCC is still lacking. In this study, the association between differentially expressed lncRNAs and ferroptosis-related genes, in 374 HCC and 50 normal hepatic samples obtained from The Cancer Genome Atlas (TCGA), was evaluated using Pearson's test, thereby identifying 24 ferroptosis-related differentially expressed lncRNAs. The least absolute shrinkage and selection operator (LASSO) algorithm and Cox regression model were used to construct and validate a prognostic risk score model from both TCGA training dataset and GEO testing dataset (GSE40144). A nine-lncRNA-based signature (CTD-2033A16.3, CTD-2116N20.1, CTD-2510F5.4, DDX11-AS1, LINC00942, LINC01224, LINC01231, LINC01508, and ZFPM2-AS1) was identified as the ferroptosis-related prognostic model for HCC, independent of multiple clinicopathological parameters. In addition, the HCC patients were divided into high-risk and low-risk groups according to the nine-lncRNA prognostic signature. The gene set enrichment analysis enrichment analysis revealed that the lncRNA-based signature might regulate the HCC immune microenvironment by interfering with tumor necrosis factor α/nuclear factor kappa-B, interleukin 2/signal transducers and activators of transcription 5, and cytokine/cytokine receptor signaling pathways. The infiltrating immune cell subtypes, such as resting memory CD4(+) T cells, follicular helper T cells, regulatory T cells, and M0 macrophages, were all significantly different between the high-risk group and the low-risk group as indicated in Spearman's correlation analysis. Moreover, a substantial increase in the expression of B7H3 immune checkpoint molecule was found in the high-risk group. Our findings provided a promising insight into ferroptosis-related lncRNAs in HCC and a personalized prediction tool for prognosis and immune responses in patients.

Serum Peptidyl-prolyl Cis-trans Isomerase NIMA-interacted 1 (Pin1) as a Non-invasive Marker for Liver Fibrosis due to Chronic Hepatitis C Virus

Background: Hepatitis C virus (HCV) may remain asymptomatic or cause liver fibrosis and cirrhosis. Objectives: We aimed to assess the relationship between serum peptidyl-prolyl cis-trans isomerase NIMA-interacted 1 (Pin1) levels and liver fibrosis due to HCV. Methods: Serum samples of successive patients with HCV genotype 1b and healthy volunteers were collected, and Pin1 levels were measured using ELISA kits. Liver fibrosis stages were calculated by the Ishak Scoring System and subdivided into two groups; stage < 3 (mild fibrosis) and ≥ 3 (advanced fibrosis). Correlation and area under receiver operating characteristics (AUROC) analysis were used to investigate the relationship between Pin1 and clinical and histopathological properties of HCV infection. Results: Ninety-four patients with HCV and 47 age- and sex-matched volunteers were included. The median age of the participants was 52, and 55% of whom were females. The mean (SD) of Pin1 serum level was significantly higher in the HCV group compared with healthy volunteers (33.94 (21.15) vs. 26.82 (8.85) pg/mL, respectively, P = 0.007). Seventy-seven (82%) and 17 (18%) of the participants showed mild and advanced fibrosis, respectively. Pin1 serum levels were significantly lower in the mild compared with advanced fibrosis group (29 (17.88) vs. 43.59 (7.98) pg/mL, respectively, P < 0.001). We found a significantly positive correlation between Pin1 serum level and liver fibrosis stage (r = 0.71, P < 0.001). The cut off of 33.04 pg/mL of Pin1 serum level showed the best sensitivity (100%) and specificity (68.4%) (AUROC = 0.81 [95% confidence interval: 0.72 - 0.90], P < 0.001) for distinguishing advanced from mild liver fibrosis. Conclusions: Serum Pin1 level may be a relevant marker for predicting liver fibrosis in HCV infected patients.

Peptidyl-Prolyl Cis/Trans Isomerase Pin1 and Alzheimer's Disease

Alzheimer’s disease (AD) is the most common cause of dementia with cognitive decline. The neuropathology of AD is characterized by intracellular aggregation of neurofibrillary tangles consisting of hyperphosphorylated tau and extracellular deposition of senile plaques composed of beta-amyloid peptides derived from amyloid precursor protein (APP). The peptidyl-prolyl cis/trans isomerase Pin1 binds to phosphorylated serine or threonine residues preceding proline and regulates the biological functions of its substrates. Although Pin1 is tightly regulated under physiological conditions, Pin1 deregulation in the brain contributes to the development of neurodegenerative diseases, including AD. In this review, we discuss the expression and regulatory mechanisms of Pin1 in AD. We also focus on the molecular mechanisms by which Pin1 controls two major proteins, tau and APP, after phosphorylation and their signaling cascades. Moreover, the major impact of Pin1 deregulation on the progression of AD in animal models is discussed. This information will lead to a better understanding of Pin1 signaling pathways in the brain and may provide therapeutic options for the treatment of AD.