PTPN2, A Key Predictor of Prognosis for Pancreatic Adenocarcinoma, Significantly Regulates Cell Cycles, Apoptosis, and Metastasis

PTPN2: Advances and perspectives in cancer treatment potential and inhibitor research

Protein tyrosine phosphatase non-receptor 2 (PTPN2) is a well-established protein tyrosine phosphatase (PTP) that counterbalances protein tyrosine kinases (PTKs) activity by dephosphorylating tyrosine residues. Accumulating evidence demonstrates that dysregulated PTPN2 expression or activity regulates cancer biology, drives immune evasion, and confers resistance to immune checkpoint blockade therapy, establishing it as a compelling therapeutic target for cancer immunotherapy. Mechanistically, PTPN2 exerts immunosuppressive effects by dephosphorylating and negatively regulating immune response signaling, thereby dampening antitumor immunity and fostering an immunosuppressive tumor microenvironment. Recent breakthroughs in PTPN2 inhibitor development, such as small molecules, natural compounds, and PROTAC degraders, have shown promising efficacy in restoring immune-mediated tumor control. However, the anti-tumor therapy targeting PTPN2 still faces challenges, including its controversial role in some tumors, potential side effects, and the lack of highly effective and selective antagonists. In this comprehensive review, we synthesize the crucial functions of PTPN2 in tumor progression and immune regulation, systematically present the latest research progress of PTPN2 inhibitors, critically analyze unresolved hurdles in drug development, and provide strategic perspectives on addressing these challenges, with the hope of accelerating the clinical translation of PTPN2-targeted therapy from bench to bedside.

TCPTP inhibition as a novel therapeutic strategy for esophageal squamous cell carcinoma: discovery and efficacy of COH29

Esophageal squamous cell carcinoma (ESCC) is a malignant tumor that poses a serious threat to human health and is often associated with poor prognosis. Therefore, it is urgent to explore new therapeutic strategies to improve the survival rate of patients with ESCC. T cell protein tyrosine phosphatase (TCPTP) has been reported as a complicated factor in cancer. In this study, we found that TCPTP was highly expressed in ESCC tissues and suppression of TCPTP can effectively inhibit the proliferation of ESCC cells in vitro and in vivo. To identify potential TCPTP inhibitors, we employed a comprehensive research approach encompassing virtual screening, pull down assay, and cellular thermal shift assay. This led to the discovery of two promising candidates: COH29 and gallocatechin gallate (GCG). Both compounds showed inhibitory effects on ESCC cell proliferation, with COH29 displaying superior efficacy. Further enzyme kinetics assay and molecular dynamics simulations confirmed COH29's unique ability to bind to both the substrate and allosteric sites of TCPTP, making it a promising lead compound for future inhibitor development. Flow cytometry analysis revealed that COH29 treatment caused cell cycle arrest in the G1 phase in ESCC cells. In vivo studies further validated COH29's robust growth suppression of ESCC, highlighting its potential as a therapeutic agent.

Comprehensive analysis of protein post-translational modifications reveals PTPN2-STAT1-AOX axis-mediated tumor progression in hepatocellular carcinomas

Hepatocellular carcinoma (HCC) is a common malignant tumor. Although the proteomics of HCC is well studied, the landscape of post-translational modifications (PTMs) in HCC is poorly understood. The PTMs themselves and their crosstalk might be deeply involved in HCC development and progression. Herein, we investigated nine types of PTMs in paired tumor and normal tissues from nine patients with HCC using the label-free quantitative liquid chromatography with tandem mass spectrometry (LC-MS)-based technique. We identified >60,000 modified sites, and found that phosphorylation and ubiquitination were two most frequently changed PTMs between tumor and normal tissues. Crosstalk between malonylation-ubiquitination, phosphorylation-ubiquitination, and succinylation-propionylation were most significant among all PTMs. Further analysis revealed that Thr-160 of CDK2 regulated EZH2 via H3K27me3, and proposed a PTPN2-STAT1-AOX1 axis for HCC development through driver PTM exploration. In conclusion, our study provides a database of multiple PTMs in HCC, which might help to understand the biology of HCC and reveal novel targets for drug development.

A Medicinal Chemistry Perspective on Protein Tyrosine Phosphatase Nonreceptor Type 2 in Tumor Immunology

PTPN2 (protein tyrosine phosphatase nonreceptor type 2) is an important member of the protein tyrosine phosphatase (PTP) family. It plays a crucial role in dephosphorylating tyrosine-phosphorylated proteins and modulating critical signaling pathways associated with T-cell receptors, IL-2, IFNγ, and various cytokines. In recent years, the PTPN2's biological role has been clarified, particularly since its association with tumor immunology was gradually revealed in 2017, making it a star target for cancer immunotherapy. The dual inhibitor AC484, which targets both PTPN2 and PTP1B, is currently undergoing phase I clinical trials. This advancement has attracted great interest from researchers to develop new drugs based on its unique structure. This review outlines the structural modification processes of PTPN2-targeted agents, focusing primarily on inhibitors and degraders. Finally, this review endeavors to provide a comprehensive perspective on the evolving field of PTPN2-targeted drug discovery for tumor immunotherapy, offering valuable insights for future drug development.

Protein tyrosine phosphatase nonreceptor 2: A New biomarker for digestive tract cancers

In this editorial, the roles of protein tyrosine phosphatase nonreceptor 2 (PTPN2) in oncogenic transformation and tumor behavior and its potential as a therapeutic target in the context of gastrointestinal (GI) cancers are presented with respect to the article by Li et al published in ninth issue of the World Journal of Gastrointestinal Oncology. PTPN2 is a member of the protein tyrosine phosphatase family of signaling proteins that play crucial roles in the regulation of inflammation and immunity. Accordingly, early findings highlighted the contribution of PTPN2 to the pathogenesis of inflammatory and autoimmune disorders related to its dysfunction. On the other hand, recent studies have indicated that PTPN2 has many different roles in different cancer types, which is associated with the complexity of its regulatory network. PTPN2 dephosphorylates and inactivates EGFR, SRC family kinases, JAK1 and JAK3, and STAT1, STAT3, and STAT5 in cell type- and context-dependent manners, which indicates that PTPN2 can perform either prooncogenic or anti-oncogenic functions depending on the tumor subtype. While PTPN2 has been suggested as a potential therapeutic target in cancer treatment, to the best of ourknowledge, no clear treatment protocol has referred to PTPN2. Although there are only few studies that investigated PTPN2 expression in the GI system cancers, which is a potential limitation, the association of this protein with tumor behavior and the influence of PTPN2 on many therapy-related signaling pathways emphasize that PTPN2 could serve as a new molecular biomarker to predict tumor behavior and as a target for therapeutic intervention against GI cancers. In conclusion, more studies should be performed to better understand the prognostic and therapeutic potential of PTPN2 in GI tumors, especially in tumors resistant to therapy.

ZP3 Expression in Pancreatic Adenocarcinoma: Its Implications for the Prognosis and Therapy

BACKGROUND

The role of Zona pellucida glycoprotein 3 (ZP3) is unclear in pancreatic adenocarcinoma (PAAD).

OBJECTIVE

This study aimed to explore the role of ZP3 in PAAD.

METHODS

A comparative analysis of ZP3 gene expression was performed to discern differences between various types of cancer and PAAD, leveraging data sourced from The Cancer Genome Atlas (TCGA). This study aimed to assess the role of ZP3 as a potential diagnostic marker for PAAD. The relationship between ZP3 levels and clinical characteristics, as well as patient outcomes, was scrutinized. Additionally, genomic enrichment analysis was carried out to uncover the underlying regulatory mechanisms associated with ZP3. The study further delved into the association of ZP3 with immune system interactions, checkpoint gene expression, Tumor Mutational Burden (TMB), microsatellite instability (MSI), and tumor stemness index (mRNAsi). The aberrant expression patterns of ZP3 in PAAD cell cultures were confirmed through the application of quantitative reverse transcription PCR (qRT-PCR) techniques.

RESULTS

ZP3 exhibited aberrant expression in both pan-cancer and PAAD. A significant correlation was observed between increased levels of ZP3 expression in PAAD patients and histologic grade (p = 0.026). Elevated ZP3 expression in PAAD was found to be significantly associated with poorer overall survival (p = 0.003), progression-free survival (p = 0.012), and disease-specific survival (p = 0.002). In PAAD, the level of ZP3 gene expression was statistically significant (p < 0.001) and recognized as a key determinant of patient prognosis. ZP3 exhibited associations with various biological pathways, including primary immunodeficiency, oxidative phosphorylation, and other pathways. ZP3 expression demonstrated correlations with immune infiltration, immune checkpoint genes, TMB, MSI, and mRNAsi in PAAD. Moreover, a pronounced negative correlation was detected between ZP3 expression levels and the therapeutic effectiveness of various medications, including selumetinib, bleomycin, FH535, docetaxel, and tanespimycin, within the context of PAAD. Elevated levels of ZP3 were consistently observed in cell line models of PAAD.

CONCLUSION

ZP3 has the potential to serve as a prognostic biomarker and therapeutic target for patients with PAAD.

Regulation of protein phosphorylation by PTPN2 and its small-molecule inhibitors/degraders as a potential disease treatment strategy

Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) is an enzyme that dephosphorylates proteins with tyrosine residues, thereby modulating relevant signaling pathways in vivo. PTPN2 acts as tumor suppressor or tumor promoter depending on the context. In some cancers, such as colorectal, and lung cancer, PTPN2 defects could impair the protein tyrosine kinase pathway, which is often over-activated in cancer cells, and inhibit tumor development and progression. However, PTPN2 can also suppress tumor immunity by regulating immune cells and cytokines. The structure, functions, and substrates of PTPN2 in various tumor cells were reviewed in this paper. And we summarized the research status of small molecule inhibitors and degraders of PTPN2. It also highlights the potential opportunities and challenges for developing PTPN2 inhibitors as anticancer drugs.

Protein tyrosine phosphatase non-receptor II: A possible biomarker of poor prognosis and mediator of immune evasion in hepatocellular carcinoma

BACKGROUND

The incidence of primary liver cancer is increasing year by year. In 2022 alone, more than 900000 people were diagnosed with liver cancer worldwide, with hepatocellular carcinoma (HCC) accounting for 75%-85% of cases. HCC is the most common primary liver cancer. China has the highest incidence and mortality rate of HCC in the world, and it is one of the malignant tumors that seriously threaten the health of Chinese people. The onset of liver cancer is occult, the early cases lack typical clinical symptoms, and most of the patients are already in the middle and late stage when diagnosed. Therefore, it is very important to find new markers for the early detection and diagnosis of liver cancer, improve the therapeutic effect, and improve the prognosis of patients. Protein tyrosine phosphatase non-receptor 2 (PTPN2) has been shown to be associated with colorectal cancer, triple-negative breast cancer, non-small cell lung cancer, and prostate cancer, but its biological role and function in tumors remain to be further studied.

AIM

To combine the results of relevant data obtained from The Cancer Genome Atlas (TCGA) to provide the first in-depth analysis of the biological role of PTPN2 in HCC.

METHODS

The expression of PTPN2 in HCC was first analyzed based on the TCGA database, and the findings were then verified by immunohistochemical staining, quantitative real-time polymerase chain reaction (qRT-PCR), and immunoblotting. The value of PTPN2 in predicting the survival of patients with HCC was assessed by analyzing the relationship between PTPN2 expression in HCC tissues and clinicopathological features. Finally, the potential of PTPN2 affecting immune escape of liver cancer was evaluated by tumor immune dysfunction and exclusion and immunohistochemical staining.

RESULTS

The results of immunohistochemical staining, qRT-PCR, and immunoblotting in combination with TCGA database analysis showed that PTPN2 was highly expressed and associated with a poor prognosis in HCC patients. Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed that PTPN2 was associated with various pathways, including cancer-related pathways, the Notch signaling pathway, and the MAPK signaling pathway. Gene Set Enrichment Analysis showed that PTPN2 was highly expressed in various immune-related pathways, such as the epithelial mesenchymal transition process. A risk model score based on PTPN2 showed that immune escape was significantly enhanced in the high-risk group compared with the low-risk group.

CONCLUSION

This study investigated PTPN2 from multiple biological perspectives, revealing that PTPN2 can function as a biomarker of poor prognosis and mediate immune evasion in HCC.

STAT3 drives the malignant progression of low-grade gliomas through modulating the expression of STAT1, FOXO1, and MYC

Low-grade glioma (LGG) is a prevalent and lethal primary brain malignancy, with most patients succumbing to recurrence and progression. The signal transducer and activator of transcription (STAT) family has long been implicated in tumor initiation and progression. However, a comprehensive evaluation of the expression status and overall function of STAT genes in LGG remains largely unreported. In this study, we investigated the association between the expression of STAT family genes and the progression of LGG. Through a comprehensive analysis that combined bioinformatics screening and validation assays, we determined that STAT1, STAT3, and STAT5A were upregulated and contributed to the malignant progression of LGG. Notably, our findings suggest that STAT3 is a critical prognostic marker that regulates the progression of LGG. STAT3 emerged as the most significant prognostic indicator governing the advancement of LGG. Additionally, our inquiry into the STAT3-binding proteins and differentially expressed-correlated genes (DEGs) revealed that STAT3 played a pivotal role in the progression of LGG by stimulating the expression of STAT1, FOXO1, and MYC. In summary, our recent study conducted a thorough analysis of the STAT family genes and revealed that directing therapeutic interventions towards STAT3 holds potential as a viable strategy for treating patients with LGG.

CENPN contributes to pancreatic carcinoma progression through the MDM2-mediated p53 signaling pathway

Introduction

We undertook an in-depth investigation of the data pertaining to pancreatic adenocarcinoma (PAAD) to identify potential targets for the development of precision therapies.

Material and methods

The construction of a protein-protein interaction (PPI) network was based on overlapping differentially expressed genes (DEGs) identified in the GSE16515, GSE32676, and GSE125158 datasets. A subsequent bioinformatic analysis was performed on the interconnected genes within the PPI network, leading to the identification of the central gene, CENPN. In vitro experimentation such as CCK8 and Transwell experiments was employed to elucidate the impact of CENPN expression patterns on PAAD cell proliferation, migration, and invasion. Furthermore, the investigation revealed through comprehensive enrichment analysis that the pivotal signaling pathway associated with CENPN is the p53 signaling pathway.

Results

Following a comprehensive bioinformatic analysis of 161 concordant differentially expressed genes (DEGs) across three microarray datasets, CENPN emerged as the central gene under investigation. Overexpression of CENPN in pancreatic adenocarcinoma (PAAD) was associated with unfavorable patient outcomes and heightened sensitivity to four PAAD therapies: gemcitabine, docetaxel, paclitaxel, and sunitinib. Reduced CENPN expression impeded PAAD cell proliferation, migration, and invasion; however, these effects were counteracted upon upregulation of CENPN expression. Additionally, CENPN interacted with MDM2, promoting PAAD progression by targeting the p53 signaling pathway.

Conclusions

The findings of our study substantiate that CENPN is associated with the pathogenesis of PAAD. Consequently, CENPN appears to be a promising candidate for targeted precision therapy in clinical applications.

PCDH1, a poor prognostic biomarker and potential target for pancreatic adenocarcinoma metastatic therapy

BACKGROUND

Pancreatic adenocarcinoma (PAAD) is an aggressive solid tumour characterised by few early symptoms, high mortality, and lack of effective treatment. Therefore, it is important to identify new potential therapeutic targets and prognostic biomarkers of PAAD.

METHODS

The Cancer Genome Atlas and Genotype-Tissue Expression databases were used to identify the expression and prognostic model of protocadherin 1 (PCDH1). The prognostic performance of risk factors and diagnosis of patients with PAAD were evaluated by regression analysis, nomogram, and receiver operating characteristic curve. Paraffin sections were collected from patients for immunohistochemistry (IHC) analysis. The expression of PCDH1 in cells obtained from primary tumours or metastatic biopsies was identified using single-cell RNA sequencing (scRNA-seq). Real-time quantitative polymerase chain reaction (qPCR) and western blotting were used to verify PCDH1 expression levels and the inhibitory effects of the compounds.

RESULTS

The RNA and protein levels of PCDH1 were significantly higher in PAAD cells than in normal pancreatic ductal cells, similar to those observed in tissue sections from patients with PAAD. Aberrant methylation of the CpG site cg19767205 and micro-RNA (miRNA) hsa-miR-124-1 may be important reasons for the high PCDH1 expression in PAAD. Up-regulated PCDH1 promotes pancreatic cancer cell metastasis. The RNA levels of PCDH1 were significantly down-regulated following flutamide treatment. Flutamide reduced the percentage of PCDH1 RNA level in PAAD cells Panc-0813 to < 50%. In addition, the PCDH1 protein was significantly down-regulated after Panc-0813 cells were incubated with 20 µM flutamide and proves to be a potential therapeutic intervention for PAAD.

CONCLUSION

PCDH1 is a key prognostic biomarker and promoter of PAAD metastasis. Additionally, flutamide may serve as a novel compound that down-regulates PCDH1 expression as a potential treatment for combating PAAD progression and metastasis.

Small molecule inhibitors for cancer immunotherapy and associated biomarkers - the current status

Following the success of cancer immunotherapy using large molecules against immune checkpoint inhibitors, the concept of using small molecules to interfere with intracellular negative regulators of anti-tumor immune responses has emerged in recent years. The main targets for small molecule drugs currently include enzymes of negative feedback loops in signaling pathways of immune cells and proteins that promote immunosuppressive signals within the tumor microenvironment. In the adaptive immune system, negative regulators of T cell receptor signaling (MAP4K1, DGKα/ζ, CBL-B, PTPN2, PTPN22, SHP1), co-receptor signaling (CBL-B) and cytokine signaling (PTPN2) have been preclinically validated as promising targets and initial clinical trials with small molecule inhibitors are underway. To enhance innate anti-tumor immune responses, inhibitory immunomodulation of cGAS/STING has been in the focus, and inhibitors of ENPP1 and TREX1 have reached the clinic. In addition, immunosuppressive signals via adenosine can be counteracted by CD39 and CD73 inhibition, while suppression via intratumoral immunosuppressive prostaglandin E can be targeted by EP2/EP4 antagonists. Here, we present the status of the most promising small molecule drug candidates for cancer immunotherapy, all residing relatively early in development, and the potential of relevant biomarkers.

Extracellular Matrix- and Integrin Adhesion Complexes-Related Genes in the Prognosis of Prostate Cancer Patients' Progression-Free Survival

Prostate cancer is a heterogeneous disease, and one of the main obstacles in its management is the inability to foresee its course. Therefore, novel biomarkers are needed that will guide the treatment options. The extracellular matrix (ECM) is an important part of the tumor microenvironment that largely influences cell behavior. ECM components are ligands for integrin receptors which are involved in every step of tumor progression. An underlying characteristic of integrin activation and ligation is the formation of integrin adhesion complexes (IACs), intracellular structures that carry information conveyed by integrins. By using The Cancer Genome Atlas data, we show that the expression of ECM- and IACs-related genes is changed in prostate cancer. Moreover, machine learning methods revealed that they are a source of biomarkers for progression-free survival of patients that are stratified according to the Gleason score. Namely, low expression of FMOD and high expression of PTPN2 genes are associated with worse survival of patients with a Gleason score lower than 9. The FMOD gene encodes protein that may play a role in the assembly of the ECM and the PTPN2 gene product is a protein tyrosine phosphatase activated by integrins. Our results suggest potential biomarkers of prostate cancer progression.

A patient-specific functional module and path identification technique from RNA-seq data

With the advancement of new technologies, a huge amount of high dimensional data is being generated which is opening new opportunities and challenges to the study of cancer and diseases. In particular, distinguishing the patient-specific key components and modules which drive tumorigenesis is necessary to analyze. A complex disease generally does not initiate from the dysregulation of a single component but it is the result of the dysfunction of a group of components and networks which differs from patient to patient. However, a patient-specific network is required to understand the disease and its molecular mechanism. We address this requirement by constructing a patient-specific network by sample-specific network theory with integrating cancer-specific differentially expressed genes and elite genes. By elucidating patient-specific networks, it can identify the regulatory modules, driver genes as well as personalized disease networks which can lead to personalized drug design. This method can provide insight into how genes are associating with each other and characterized the patient-specific disease subtypes. The results show that this method can be beneficial for the detection of patient-specific differential modules and interaction between genes. Extensive analysis using existing literature, gene enrichment and survival analysis for three cancer types STAD, PAAD and LUAD shows the effectiveness of this method over other existing methods. In addition, this method can be useful for personalized therapeutics and drug design. This methodology is implemented in the R language and is available at https://github.com/riasatazim/PatientSpecificRNANetwork.

Comprehensive analysis of PTPN family expression and prognosis in acute myeloid leukemia

Background: Tyrosyl phosphorylation is carried out by a group of enzymes known as non-receptor protein tyrosine phosphatases (PTPNs). In the current investigation, it is hoped to shed light on the relationships between the expression patterns of PTPN family members and the prognosis of acute myeloid leukemia (AML). Methods: PTPN expression was examined using GEPIA and GEO databases. To investigate the connection between PTPN expression and survival in AML patients, we downloaded data from the Broad TCGA Firehose and Clinical Proteomic Tumor Analysis (CPTAC) of the Cancer Genome Atlas (TCGA). We used quantitative real-time PCR (qRT-PCR) to confirm that essential genes were performed in clinical samples and cell lines. We then used western blot to verify that the genes expressed in the above databases were positive in normal tissues, AML patient samples, and AML cell lines. Next, we investigated associations between genome-wide expression profiles and PTPN6 expression using the GEO datasets. We investigated the interactive exploration of multidimensional cancer genomics using the cBioPortal datasets. Using the DAVID database, a study of gene ontology enrichment was performed. The protein-protein interaction (PPI) network was created using the STRING portal, and the gene-gene interaction network was performed using GeneMANIA. Results: Data from GEO and GEPIA revealed that most PTPN family members were linked to AML. Patients with leukemia have elevated levels of several PTPN members. All of the AML patients' poor overall survival (OS, p < .05) was significantly linked with higher expression of PTPN1, PTPN6, and PTPN7. Additionally, clinical samples showed that the expression of PTPN 6, PTPN 7, PTPN 13, and PTPN 14 was higher than normal in AML patients (p = .0116, p = .0034, p = .0092, and p = .0057, respectively) and AML cell lines (p = .0004, p = .0035, p = .0357, and p = .0177, respectively). Western blotting results showed that the expression of PTPN6 in AML samples and AML cell lines was significantly higher than that in normal control samples. Conclusion: Differentially expressed PTPN family members were found in AML. The prognosis of patients and PTPN gene expression were shown to be correlated. PTPN6 is one of these members and may be used as an AML diagnostic and prognostic marker.

Immune checkpoint PTPN2 predicts prognosis and immunotherapy response in human cancers

Background

PTPN2, a member of the non-receptor protein tyrosine phosphatases family, holds a crucial role in tumorigenesis and cancer immunotherapy. However, most studies on the role of PTPN2 in cancer are limited to specific cancer types. Therefore, this study aimed to investigate the prognostic significance of PTPN2 in human cancers and its function in the tumor microenvironment.

Methods

To shed light on this matter, we investigated the expression level, prognostic value, genomic alterations, molecular function, immune function, and immunotherapeutic predictive ability of PTPN2 in human cancers using the TCGA, GTEx, CGGA, GEO, cBioPortal, STRING, TISCH, TIMER2.0, ESTIMATE, and TIDE databases. Furthermore, the CCK-8 assay was utilized to detect the effect of PTPN2 on cell proliferation. Cell immunofluorescence analysis was performed to probe the cellular localization of PTPN2. Western blot was applied to examine the molecular targets downstream of PTPN2. Finally, a Nomogram model was constructed using the TCGA-LGG cohort and evaluated with calibration curves and time-dependent ROCs.

Results

PTPN2 was highly expressed in most cancers and was linked to poor prognosis in ACC, GBM, LGG, KICH, and PAAD, while the opposite was true in OV, SKCM, and THYM. PTPN2 knockdown promoted the proliferation of melanoma cells, while significantly inhibiting proliferation in colon cancer and glioblastoma cells. In addition, TC-PTP, encoded by the PTPN2 gene, was primarily localized in the nucleus and cytoplasm and could negatively regulate the JAK/STAT and MEK/ERK pathways. Strikingly, PTPN2 knockdown significantly enhanced the abundance of PD-L1. PTPN2 was abundantly expressed in Mono/Macro cells and positively correlated with multiple immune infiltrating cells, especially CD8⁺ T cells. Notably, DLBC, LAML, OV, and TGCT patients in the PTPN2-high group responded better to immunotherapy, while the opposite was true in ESCA, KIRC, KIRP, LIHC, and THCA. Finally, the construction of a Nomogram model on LGG exhibited a high prediction accuracy.

Conclusion

Immune checkpoint PTPN2 is a powerful biomarker for predicting prognosis and the efficacy of immunotherapy in cancers. Mechanistically, PTPN2 negatively regulates the JAK/STAT and MEK/ERK pathways and the abundance of PD-L1.

Critical roles of PTPN family members regulated by non-coding RNAs in tumorigenesis and immunotherapy

Since tyrosine phosphorylation is reversible and dynamic in vivo, the phosphorylation state of proteins is controlled by the opposing roles of protein tyrosine kinases (PTKs) and protein tyrosine phosphatase (PTPs), both of which perform critical roles in signal transduction. Of these, intracellular non-receptor PTPs (PTPNs), which belong to the largest class I cysteine PTP family, are essential for the regulation of a variety of biological processes, including but not limited to hematopoiesis, inflammatory response, immune system, and glucose homeostasis. Additionally, a substantial amount of PTPNs have been identified to hold crucial roles in tumorigenesis, progression, metastasis, and drug resistance, and inhibitors of PTPNs have promising applications due to striking efficacy in antitumor therapy. Hence, the aim of this review is to summarize the role played by PTPNs, including PTPN1/PTP1B, PTPN2/TC-PTP, PTPN3/PTP-H1, PTPN4/PTPMEG, PTPN6/SHP-1, PTPN9/PTPMEG2, PTPN11/SHP-2, PTPN12/PTP-PEST, PTPN13/PTPL1, PTPN14/PEZ, PTPN18/PTP-HSCF, PTPN22/LYP, and PTPN23/HD-PTP, in human cancer and immunotherapy and to comprehensively describe the molecular pathways in which they are implicated. Given the specific roles of PTPNs, identifying potential regulators of PTPNs is significant for understanding the mechanisms of antitumor therapy. Consequently, this work also provides a review on the role of non-coding RNAs (ncRNAs) in regulating PTPNs in tumorigenesis and progression, which may help us to find effective therapeutic agents for tumor therapy.