p53-R273H upregulates neuropilin-2 to promote cell mobility and tumor metastasis

Mutant p53 achieves function by regulating EGR1 to induce epithelial mesenchymal transition

The epithelial-mesenchymal transition (EMT) plays a crucial role in lung cancer metastasis, rendering it a promising therapeutic target. Research has shown that non-small cell lung cancer (NSCLC) with p53 mutations exhibits an increased tendency for cancer metastasis. However, the exact contribution of the p53-R273H mutation to tumor metastasis remains uncertain in the current literature. Our study established the H1299-p53-R273H cell model successfully by transfecting the p53-R273H plasmid into H1299 cells. We observed that p53-R273H promotes cell proliferation, migration, invasion, and EMT through CCK-8, wound healing, transwell, western blot and immunofluorescence assays. Notably, the expression of EGR1 was increased in H1299-p53-R273H cells. Knocking out EGR1 in these cells hindered the progression of EMT. ChIP-PCR experiments revealed that p53-R273H binds to the EGR1 promoter sequence, thereby regulating its expression. These findings suggest that p53-R273H triggers EMT by activating EGR1, thereby offering a potential therapeutic approach for lung cancer treatment.

Deficiency of inflammation-sensing protein neuropilin-2 in myeloid-derived macrophages exacerbates colitis via NF-κB activation

Neuropilin-2 (NRP2) is a multifunctional protein engaged in the regulation of angiogenesis, lymphangiogenesis, axon guidance, and tumor metastasis, but its function in colitis remains unclear. Here, we found that NRP2 was an inflammation-sensing protein rapidly and dramatically induced in myeloid cells, especially in macrophages, under inflammatory contexts. NRP2 deficiency in myeloid cells exacerbated dextran sulfate sodium salt-induced experimental colitis by promoting polarization of M1 macrophages and colon injury. Mechanistically, NRP2 could be induced via NF-κB activation by TNF-α in macrophages, but exerted an inhibitory effect on NF-κB signaling, forming a negative feedback loop with NF-κB to sense and alleviate inflammation. Deletion of NRP2 in macrophages broke this negative feedback circuit, leading to NF-κB overactivation, inflammatory exacerbation, and more severe colitis. Collectively, these findings reveal inflammation restriction as a role for NRP2 in macrophages under inflammation contexts and suggest that NRP2 in macrophages may relieve inflammation in inflammatory bowel disease. © 2023 The Pathological Society of Great Britain and Ireland.

Role of Neuropilin-2-mediated signaling axis in cancer progression and therapy resistance

Neuropilins (NRPs) are transmembrane proteins involved in vascular and nervous system development by regulating angiogenesis and axon guidance cues. Several published reports have established their role in tumorigenesis. NRPs are detectable in tumor cells of several cancer types and participate in cancer progression. NRP2 is also expressed in endothelial and immune cells in the tumor microenvironment and promotes functions such as lymphangiogenesis and immune suppression important for cancer progression. In this review, we have taken a comprehensive approach to discussing various aspects of NRP2-signaling in cancer, including its regulation, functional significance in cancer progression, and how we could utilize our current knowledge to advance the studies and target NRP2 to develop effective cancer therapies.

Quantitative detections of TP53 gene mutations improve the diagnosis and prognostic prediction of biliary tract cancers using droplet digital PCR

OBJECTIVE

Biliary tract cancer (BTC) is a rare malignancy and lack of effective diagnostic and prognostic marker. Here, we aimed to investigate the clinical implication of TP53 mutation detection in BTC using droplet digital PCR (ddPCR).

METHODS

TP53 gene (loci p.R175H, p.R248Q, p.R248W, and p.R273H) mutation frequencies of 45 pairs of tumor tissues (TTs) and adjacent normal tissues (ANTTs) were analyzed, respectively, using ddPCR. Meanwhile, the same detections were conducted in plasma cell-free DNA (cfNDA) of 156 subjects including BTC, disease control (DC), and healthy controls (HC). The logistic regression algorithm was established to identify BTC. The correlations between mutations and clinicopathological features as well as the effects of TP53 mutation frequency on BTC prognosis were assessed.

RESULTS

The higher mutation of p.R175H was found in TTs compared with ANTT (p = 0.006). The mutation at p.R273H in cfDNA was also higher in BTC when compared with DC and HC (p < 0.05). The logistic algorithms combining p.R273H mutation demonstrated the higher diagnostic efficacy trend than carbohydrate antigen 19-9 (CA19-9), carcinoembryonic antigen (CEA), and alpha-fetoprotein (AFP) in identifying BTC from DC (the area under the curves of the algorithm: 0.845, 95% CI:0.775-0.914). The median overall survival (OS) and progression-free survival (PFS) were significantly shorter when the BTC patients harboring the p.R273H mutation (OS: p = 0.032; PFS: p = 0.046).

CONCLUSION

This study revealed for the first time that the quantitative TP53 mutations using the ddPCR might serve as a potential genetic biomarker for BTC diagnosis and prognosis assessment.

uPAR: An Essential Factor for Tumor Development

Tumorigenesis is closely related to the loss of control of many genes. Urokinase-type plasminogen activator receptor (uPAR), a glycolipid-anchored protein on the cell surface, is controlled by many factors in tumorigenesis and is expressed in many tumor tissues. In this review, we summarize the regulatory effects of the uPAR signaling pathway on processes and factors related to tumor progression, such as tumor cell proliferation, adhesion, metastasis, glycolysis, tumor microenvironment and angiogenesis. Overall, the evidence accumulated to date suggests that uPAR induction by tumor progression may be one of the most important factors affecting therapeutic efficacy. An improved understanding of the interactions between uPAR and its coreceptors in cancer will provide critical biomolecular information that may help to better predict the disease course and response to therapy.

NRP2, a potential biomarker for oral squamous cell carcinoma

BACKGROUND

Neuropilin-2 (NRP2) is a single chain transmembrane glycoprotein that acts as a co-receptor of VEGF and is related to the pathogenesis of various tumors closely. However, the clinical significance of NRP2 in oral squamous cell carcinoma (OSCC) is unclear.

PURPOSE

The objective of this study was to investigate the role of NRP2 in the pathogenesis of OSCC and explore the associated mechanisms.

MATERIALS AND METHODS

GEPIA (gene expression profiling interactive analysis) was used to analyze the expression of NRP2 in OSCC. Immunohistochemistry and RT-qPCR were used to detect NRP2 expression in 80 OSCC samples. The clinical correlations and prognostic significance of NRP2 expression were evaluated. In addition, the biological functions of OSCC cells transfected with shNRP2 were evaluated. The expression levels of β-catenin, C-myc, cyclin D1, and MMP-2 in Wnt/β-catenin signaling pathway were assessed by RT-qPCR after inhibiting the expression of NRP2 in SCC-25 cell line.

RESULTS

Analysis of cases using GEPIA revealed that NRP2 was substantially upregulated in OSCC. NRP2 expression was also significantly higher in our OSCC samples than in the controls. Elevated expression of NRP2 was correlated with lymph node metastasis (P<0.01) and distant metastasis (P<0.05) in OSCC patients, and high NRP2 levels, lymph node metastasis, and distant metastasis were associated with poor prognosis (Kaplan-Meier analysis; P<0.05). Univariate and multivariate Cox analysis showed that lymph node metastasis, distant metastasis, and NRP2 expression were independent risk factors for overall survival (OS) and disease-free survival (DFS) in OSCC patients (P<0.05). Furthermore, the proliferation, migration, and invasion of OSCC cells were inhibited by shNRP2. Following inhibiting of NRP2 expression in the SCC-25 cell line, the expression levels of β-catenin, C-myc, cyclin D1, and MMP-2 were reduced (P<0.05).

CONCLUSION

This study shows that NRP2 functions as a tumor promoter gene in OSCC by affecting the proliferation, migration, and invasion of OSCC cells and downregulating the Wnt/β-catenin pathway. These results highlight the potential role for NRP2 as a clinical diagnostic marker.

p53-R273H promotes cancer cell migration via upregulation of neuraminidase-1

Accumulating evidence indicates that hotspot p53 mutants have gain-of-function in promoting cell migration and tumor metastasis. However, the molecular mechanisms are not completely understood. Here, we show that a hotspot mutation, p53-R273H, promotes non-small cell lung cancer (NSCLC) cell migration and upregulates the mRNA and protein expression of neuraminidase-1 (NEU1), a sialidase involved in cell proliferation, cell migration and tumorigenesis. Silencing of NEU1 leads to upregulation of integrin β4 which significantly inhibits NSCLC cell migration induced by p53-R273H. Mechanistically, p53-R273H promotes NEU1 transcription via activation of AKT signaling. Importantly, NEU1 expression is upregulated in human NSCLC samples harboring mutant p53 and is associated with poor clinical outcome. Overall, this study highlights an important role of NEU1 in p53-R273H-induced NSCLC cell migration and provides a potential target for NSCLC diagnosis and treatment.

Hotspot mutant p53-R273H inhibits KLF6 expression to promote cell migration and tumor metastasis

Hotspot p53 mutant proteins often gain novel functions in promoting tumor metastases. However, the molecular mechanisms by which mutant p53 exerts gain-of-function in cancer are not totally understood. In this study, we demonstrate that hotspot mutant p53, p53-R273H, promotes cell scattering growth and migration via inhibiting the expression of Krupple-like factor 6 (KLF6), a Zinc finger transcription factor and a documented tumor suppressor. Restoration of KLF6 increases the expression of E-cadherin downregulated by p53-R273H and inhibits p53-R273H-induced cell migration and tumor metastasis. Further, p53-R273H reduces KLF6 transcription by upregulating EGFR expression which in turn activates AKT–FOXO1 axis. Pharmacological inhibitor of AKT, MK2206, rescues KLF6 expression and suppresses p53-R273H-induced cell migration. Clinical analyses reveal that KLF6 expression is decreased in human breast cancer specimens harboring p53 mutations, and negatively correlated with EGFR expression in human breast cancer. In addition, low expression of KLF6 is associated with poor overall survival (OS) and relapse-free survival (RFS) in p53 mutated human breast cancer patients. Together, these results reveal an important role for EGFR–AKT–FOXO1–KLF6–E-cadherin axis in mutant p53-induced cell migration and tumor metastasis.

TP53 mutational landscape of metastatic head and neck cancer reveals patterns of mutation selection

Background

Head and neck squamous cell carcinoma is a heterogeneous disease with respect to the anatomic site of the primary tumor. On the other hand, it is highly recurrent, and once metastatic, it is associated with poor prognosis. TP53 is the most commonly mutated gene in primary disease. TP53 mutations occur in different structural elements of the protein while the biological outcome can be diverse.

Methods

Here we aimed to find differences in the mutation profile of TP53 in primary and metastatic disease and the impact of TP53 mutations in metastasis, specific copy number alterations, tumor mutation burden and response to immune checkpoint inhibitors. Somatic mutation and clinical data for 512 primary and 134 metastatic biopsies were studied.

Findings

Overall TP53 mutation frequency is significantly lower in metastases compared to primary tumors. One the other hand, missense mutations in the DNA binding region are significantly enriched in metastases and are associated with a common fragile site in chromosome 11, leading to amplification and overexpression of genes with established role in metastasis. Finally, TP53 mutations are associated with higher TMB score in metastatic but not primary tumors, and poorer response to immune checkpoint inhibitors for the latter.

Interpretation

TP53 mutations affect clinical and molecular aspects of head and neck tumorigenesis including metastasis, genetic alterations and therapeutic response.

Funding

This work was supported by a Horizon 2020 grant (801347) to AK, and a Greek General Secretariat for Research and Technology and the Hellenic Foundation for Research and Innovation grant (472‐EpiNotch) to TR.

The genetic script of metastasis

Metastasis is a pivotal event that changes the course of cancers from benign and treatable to malignant and difficult to treat, resulting in the demise of patients. Understanding the genetic control of metastasis is thus crucial to develop efficient and sustainable targeted therapies. Here we discuss the alterations in epigenetic mechanisms, transcription, chromosomal instability, chromosome imprinting, non-coding RNAs, coding RNAs, mutant RNAs, enhancers, G-quadruplexes, and copy number variation to dissect the genetic control of metastasis. We conclude that the genetic control of metastasis is predominantly executed through epithelial to mesenchymal transition and evasion of cell death. We discuss how genetic regulatory mechanisms can be harnessed for therapeutic purposes to achieve sustainable control over cancer metastasis.

Gain-of-Function Mutant p53: All the Roads Lead to Tumorigenesis

The p53 protein is mutated in about 50% of human cancers. Aside from losing the tumor-suppressive functions of the wild-type form, mutant p53 proteins often acquire inherent, novel oncogenic functions, a phenomenon termed mutant p53 gain-of-function (GOF). A growing body of evidence suggests that these pro-oncogenic functions of mutant p53 proteins are mediated by affecting the transcription of various genes, as well as by protein-protein interactions with transcription factors and other effectors. In the current review, we discuss the various GOF effects of mutant p53, and how it may serve as a central node in a network of genes and proteins, which, altogether, promote the tumorigenic process. Finally, we discuss mechanisms by which "Mother Nature" tries to abrogate the pro-oncogenic functions of mutant p53. Thus, we suggest that targeting mutant p53, via its reactivation to the wild-type form, may serve as a promising therapeutic strategy for many cancers that harbor mutant p53. Not only will this strategy abrogate mutant p53 GOF, but it will also restore WT p53 tumor-suppressive functions.

Epigenetic regulation of ferroptosis by H2B monoubiquitination and p53

Monoubiquitination of histone H2B on lysine 120 (H2Bub1) is an epigenetic mark generally associated with transcriptional activation, yet the global functions of H2Bub1 remain poorly understood. Ferroptosis is a form of non-apoptotic cell death characterized by the iron-dependent overproduction of lipid hydroperoxides, which can be inhibited by the antioxidant activity of the solute carrier family member 11 (SLC7A11/xCT), a component of the cystine/glutamate antiporter. Whether nuclear events participate in the regulation of ferroptosis is largely unknown. Here, we show that the levels of H2Bub1 are decreased during erastin-induced ferroptosis and that loss of H2Bub1 increases the cellular sensitivity to ferroptosis. H2Bub1 epigenetically activates the expression of SLC7A11. Additionally, we show that the tumor suppressor p53 negatively regulates H2Bub1 levels independently of p53's transcription factor activity by promoting the nuclear translocation of the deubiquitinase USP7. Moreover, our studies reveal that p53 decreases H2Bub1 occupancy on the SLC7A11 gene regulatory region and represses the expression of SLC7A11 during erastin treatment. These data not only suggest a noncanonical role of p53 in chromatin regulation but also link p53 to ferroptosis via an H2Bub1-mediated epigenetic pathway. Overall, our work uncovers a previously unappreciated epigenetic mechanism for the regulation of ferroptosis.

Association of p53 expression with poor prognosis in patients with triple-negative breast invasive ductal carcinoma

TP53 gene is mutated in approximately 80% of triple-negative breast cancer (TNBC). However, the prognostic significance of immunohistochemical (IHC)-detected p53 protein expression remains controversial in TNBC. In this study, we retrospectively analyzed the association between IHC-detected p53 expression and the prognosis in a cohort of 278 patients with stage I-III triple-negative breast invasive ductal carcinoma (IDC), who received surgery at the department of breast surgery in the Fourth Hospital of Hebei Medical University from 2010-01 to 2012-12. We found a positive expression ratio of IHC-detected p53 in triple-negative breast IDC of 58.6% (163/278). Furthermore, levels of expression were significantly associated with vessel tumor emboli and higher histologic grade (P = .038, P = .043, respectively), with the highest expression level observed in G3 breast cancer (64.7%). Additionally, Kaplan-Meier analysis showed that p53 expression indicated worse overall survival (OS) in the whole cohort (79.6% vs 89.6%, Log-rank test P = .025) as well as in stratified prognostic stage II patients (90.8% vs 100%, Log-rank test P = .027). The mortality risk of p53 expression patients was 2.22 times higher than that of p53 negative patients (HR: 2.222; 95%CI: 1.147-4.308). In addition, p53 expression was also associated with poor disease-free survival (DFS) (76.7% vs 86.8%, P = .020). Cox proportional hazard ratio model showed p53 expression was an independent risk factor for OS (P = .018) and DFS (P = .018) after controlling for tumor size, lymph node status, and vessel tumor emboli. Altogether, our data showed that IHC-detected p53 expression is a promising prognostic candidate for poor survival in triple-negative breast IDC patients. However, more studies are needed to determine if p53 may be applied to clinical practice as a biomarker and/or novel therapeutic target for TNBC.

Actinidia chinensis Planch root extract attenuates proliferation and metastasis of hepatocellular carcinoma by inhibiting epithelial-mesenchymal transition

ETHNO-PHARMACOLOGICAL RELEVANCE

Numerous studies have demonstrated the potent anticancer activity of various Chinese herbs. Actinidia chinensis Planch root (acRoots), a traditional Chinese medicine, functions as an antitumor and detoxifying agent and plays a role in diuresis and hemostasis. Treatment with acRoots confers strong inhibition of tumor growth in various forms of cancer. Here, we evaluated the anticancer activity and molecular mechanisms of Actinidia chinensis Planch root extract (acRoots) on hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Our previous study used mRNA chip analyses to identify the genes regulated by acRoots. Further analyses of the altered genes identified a key regulator of genes in response to acRoots. Here, the effects of acRoots on HCC cell proliferation, migration, invasion, and apoptosis were evaluated by cell counting, Transwell and apoptosis assays. In addition, the in vivo anti-HCC effects of acRoots were investigated using an HCC animal model. The expression of a key regulator of genes in response to acRoots was analyzed using quantitative polymerase chain reaction and western blotting.

RESULTS

Treatment with acRoots (10 mg/mL) had no cytotoxicity in L02 cells and had a positive effect on L02 cell viability; however, it significantly inhibited HCC cell proliferation. Treatment with acRoots downregulated DLX2 gene expression in HCC cells, and high DLX2 expression was associated with advanced stage and poor prognosis in patients with HCC. Treatment with acRoots inhibited proliferation, invasion and migration, clonality, and the epithelial-to-mesenchymal transition, and promoted the apoptosis of HCC cells by downregulating DLX2 expression. HCC cells with higher DLX2 expression were more sensitive to acRoots.

CONCLUSIONS

acRoots inhibited the malignant biological behavior of HCC cells via regulation of the epithelial-mesenchymal transition (EMT) by DLX2.

Functional Diversity of p53 in Human and Wild Animals

The common understanding of p53 function is a genome guardian, which is activated by diverse stresses stimuli and mediates DNA repair, apoptosis, and cell cycle arrest. Increasing evidence has demonstrated p53 new cellular functions involved in abundant endocrine and metabolic response for maintaining homeostasis. However, TP53 is frequently mutant in human cancers, and the mutant p53 (Mut-p53) turns to an "evil" cancer-assistant. Mut-p53-induced epithelial-mesenchymal transition (EMT) plays a crucial role in the invasion and metastasis of endocrine carcinomas, and Mut-p53 is involved in cancer immune evasion by upregulating PD-L1 expression. Therefore, Mut-p53 is a valuable treatment target for malignant tumors. Targeting Mut-p53 in correcting sequence and conformation are increasingly concerned. Interestingly, in wild animals, p53 variations contribute to cancer resistant and high longevity. This review has discussed the multiple functions of p53 in health, diseases, and nature evolution, summarized the frequently mutant sites of p53, and the mechanisms of Mut-p53-mediated metastasis and immune evasion in endocrine cancers. We have provided a new insight for multiple roles of p53 in human and wild animals.

Oncogenic Metabolism Acts as a Prerequisite Step for Induction of Cancer Metastasis and Cancer Stem Cell Phenotype

Metastasis is a major obstacle to the efficient and successful treatment of cancer. Initiation of metastasis requires epithelial-mesenchymal transition (EMT) that is regulated by several transcription factors, including Snail and ZEB1/2. EMT is closely linked to the acquisition of cancer stem cell (CSC) properties and chemoresistance, which contribute to tumor malignancy. Tumor suppressor p53 inhibits EMT and metastasis by negatively regulating several EMT-inducing transcription factors and regulatory molecules; thus, its inhibition is crucial in EMT, invasion, metastasis, and stemness. Metabolic alterations are another hallmark of cancer. Most cancer cells are more dependent on glycolysis than on mitochondrial oxidative phosphorylation for their energy production, even in the presence of oxygen. Cancer cells enhance other oncogenic metabolic pathways, such as glutamine metabolism, pentose phosphate pathway, and the synthesis of fatty acids and cholesterol. Metabolic reprogramming in cancer is regulated by the activation of oncogenes or loss of tumor suppressors that contribute to tumor progression. Oncogenic metabolism has been recently linked closely with the induction of EMT or CSC phenotypes by the induction of several metabolic enzyme genes. In addition, several transcription factors and molecules involved in EMT or CSCs, including Snail, Dlx-2, HIF-1α, STAT3, TGF-β, Wnt, and Akt, regulate oncogenic metabolism. Moreover, p53 induces metabolic change by directly regulating several metabolic enzymes. The collective data indicate the importance of oncogenic metabolism in the regulation of EMT, cell invasion and metastasis, and adoption of the CSC phenotype, which all contribute to malignant transformation and tumor development. In this review, we highlight the oncogenic metabolism as a key regulator of EMT and CSC, which is related with tumor progression involving metastasis and chemoresistance. Targeting oncometabolism might be a promising strategy for the development of effective anticancer therapy.

NRP-2 in tumor lymphangiogenesis and lymphatic metastasis

Neuropilin-2 (NRP-2) not only functions as a receptor for semaphorins, a family of neural axon guidance factors, but also interacts with VEGFs, a family of vascular endothelial growth factors. As an independent receptor or a co-receptor, NRP-2 binds to ligands VEGF-C/D, activates the VEGF-C/D-NRP-2 signaling axis, and further regulates lymphangiogenesis-associated factors in both lymphatic endothelial cells (LECs) and some tumor cells during tumor progression. Via VEGF-C/D-NRP-2 axis, NRP-2 induces LEC proliferation, reconstruction and lymphangiogenesis and subsequently promotes tumor cell migration, invasion and lymphatic metastasis. There are similarities and differences among NRP-1, NRP-2 and VEGFR-3 in chemical structure, ligand specificity, chromosomal location, soluble protein forms, cellular functions and expression profiles. High expression of NRP-2 in LECs and tumor cells has been observed in different anatomic sites, histological patterns and progression stages of various tumors, especially during tumor lymphangiogenesis and lymphatic metastasis, and therefore the NRP-2 and VEGF-C/D-NRP-2 axis are closely related to tumor development, progression, invasion, and metastasis. In addition, it is important for prognosis of tumor. The studies on NRP-2 targeted therapy have recently achieved some successes, utilizing NRP-2 blocking antibodies, NRP-2 inhibitory peptides, soluble NRP-2 antagonists, small molecule inhibitors and various NRP-2 gene therapeutic strategies.