Proteomic identification of cyclophilin A as a potential biomarker and therapeutic target in oral submucous fibrosis

The current landscape of antifibrotic therapy across different organs: A systematic approach

Fibrosis is a common pathological process that can affect virtually all the organs, but there are hardly any effective therapeutic options. This has led to an intense search for antifibrotic therapies over the last decades, with a great number of clinical assays currently underway. We have systematically reviewed all current and recently finished clinical trials involved in the development of new antifibrotic drugs, and the preclinical studies analyzing the relevance of each of these pharmacological strategies in fibrotic processes affecting tissues beyond those being clinically studied. We analyze and discuss this information with the aim of determining the most promising options and the feasibility of extending their therapeutic value as antifibrotic agents to other fibrotic conditions.

Expression profile of diagnostic genes in oral submucous fibrosis

Oral Submucous Fibrosis (OSMF) is a chronic precancerous disorder of the oral mucosa caused by chewing of areca nut and its other variants. Chewing of areca nuts leads to dysregulated expression of specific genes, leading to various premalignant or malignant disorders. This study aimed to determine the differential expression of the diagnostic genes (MYH6, TNNT3, MYL1, and TPM2) in healthy controls and OSMF patients using saliva and tissue samples, determining the histopathological grade of the clinical samples. A total of 20 patients were included in the study and were divided into two groups: Group I consisted of 10 healthy patients (control group) and Group II consisted of 10 OSMF patients. Unstimulated whole saliva samples were collected from both groups, and the tissue samples were divided into two parts: one for RT-qPCR analysis and the other for histopathological assay. The expression profile of genes concerning OSMF saliva and tissue samples was significantly upregulated compared to the healthy control, and all the clinical samples of the study were categorized into histopathological grade 1. The findings of this study concluded that these genes can be referred to as diagnostic genes for OSMF in early and very early clinical samples, and saliva can be used as a promising diagnostic tool for early OSMF studies.

Role and new insights of microfibrillar-associated protein 4 in fibrotic diseases

Fibrosis is one of the most worrisome complications of chronic inflammatory diseases, leading to tissue damage, organ failure, and ultimately, death. The most notable pathological characteristic of fibrosis is the excessive accumulation of extracellular matrix (ECM) components such as collagen and fibronectin adjacent to foci of inflammation or damage. The human microfibrillar-associated protein 4 (MFAP4), an important member of the superfamily of fibrinogen-related proteins, is considered to have an extremely important role in ECM transformation of fibrogenesis. This review summarizes the structure, characteristics, and physiological functions of MFAP4 and the importance of MFAP4 in various fibrotic diseases. Meanwhile, we elaborated the underlying actions and mechanisms of MFAP4 in the development of fibrosis, suggesting that a better understand of MFAP4 broadens novel perspective for early screening, diagnosis, prognostic risk assessment, and treatment of fibrotic diseases.

SNAI2 promotes the malignant transformation of oral leukoplakia by modulating p-EMT

OBJECTIVE

Snail family transcriptional repressor 2 (SNAI2) is a key regulator of partial epithelial-mesenchymal transition (p-EMT) and is associated with tumorigenesis. Whether SNAI2 promotes oral leukoplakia (OLK) malignant transformation by modulating p-EMT is unclear.

MATERIALS AND METHODS

This study utilized two clinical datasets (GSE26549 and GSE85195) from the Gene Expression Omnibus database, cytological experiments, and a 4-nitroquinoline 1-oxide-induced mice model to explore the role of SNAI2 in OLK malignant transformation.

RESULTS

The clinical cohort found SNAI2, as a risk factor (HR = 2.50, 95% CI: 1.08-5.79, p = 0.033), could promote OLK malignant transformation (p = 0.012). Cytological experiments indicated that SNAI2 overexpression promoted DOK cell proliferation, invasion, migration, and increase the protein expression of p-EMT relative signatures, whereas SNAI2 silencing has opposite effects. Furthermore, the mice model and clinical datasets demonstrated the expression of SNAI2 and p-EMT relative signatures were increased with OLK malignant transformation. And SNAI2 was strongly correlated with p-EMT. Besides, co-expressed genes of SNAI2 were also enriched in p-EMT relative biological processes and signaling pathways.

CONCLUSIONS

p-EMT plays a significant role in promoting the OLK malignant transformation. As an important regulator of p-EMT, SNAI2 could be a target to block the OLK malignant transformation.

Cyclophilin A binds to AKT1 and facilitates the tumorigenicity of Epstein-Barr virus by mediating the activation of AKT/mTOR/NF-κB positive feedback loop

The AKT/mTOR and NF-κB signalings are crucial pathways activated in cancers including nasopharyngeal carcinoma (NPC), which is prevalent in southern China and closely related to Epstein-Barr virus (EBV) infection. How these master pathways are persistently activated in EBV-associated NPC remains to be investigated. Here we demonstrated that EBV-encoded latent membrane protein 1 (LMP1) promoted cyclophilin A (CYPA) expression through the activation of NF-κB. The depletion of CYPA suppressed cell proliferation and facilitated apoptosis. CYPA was able to bind to AKT1, thus activating AKT/mTOR/NF-κB signaling cascade. Moreover, the use of mTOR inhibitor, rapamycin, subverted the activation of the positive feedback loop, NF-κB/CYPA/AKT/mTOR. It is reasonable that LMP1 expression derived from initial viral infection is enough to assure the constant potentiation of AKT/mTOR and NF-κB signalings. This may partly explain the fact that EBV serves as a tumor-promoting factor with minimal expression of the viral oncoprotein LMP1 in malignancies. Our findings provide new insight into the understanding of causative role of EBV in tumorigenicity during latent infection.

Delicate regulation of IL-1β-mediated inflammation by cyclophilin A

The inflammatory response is tightly regulated, but its regulatory principles are still incompletely understood. Cyclophilin A (CypA) has long been considered as a pro-inflammatory factor. Here, we discover how CypA precisely regulates interleukin-1β (IL-1β)-mediated inflammatory responses. In lipopolysaccharide-treated mice, CypA deficiency initially inhibits and then promotes lung inflammation, which is closely related to IL-1β production. Mechanistically, CypA not only facilitates pro-IL-1β processing by increasing Smurf1-mediated K63-linked ubiquitination in an ATP-dependent manner but also accelerates pro-IL-1β degradation, depending on Smurf1-mediated K48-linked ubiquitination. Moreover, in IL-1β-treated mice, CypA exacerbates lung injury by enhancing cytokine production. It also upregulates the ILK/AKT pathway by inhibiting Cyld-mediated K63-linked ILK deubiquitination, which promotes the epithelial-mesenchymal transition (EMT) to facilitate lung repair. Collectively, CypA promotes inflammation activation by increasing IL-1β production and then promotes inflammation resolution by enhancing redundant pro-IL-1β degradation and IL-1β-induced EMT, indicating the complex and delicate regulation of inflammatory response.

Integrated Proteomics Based on 2D Gel Electrophoresis and Mass Spectrometry with Validations: Identification of a Biomarker Compendium for Oral Submucous Fibrosis—An Indian Study

Oral Submucous Fibrosis (OSMF) is a chronic debilitating disease more frequently found in the South East Asian population. This disease poses a public health priority, as it is grouped under oral potentially malignant disorders, with malignant transformation rates of around 7 to 13%. Hence, early identification of high-risk OSMF patients is of the utmost importance to prevent malignant transformation. Proteomic expression profiling is a promising method for identifying differentially expressed proteins for disease prognosis and risk stratification in OSMF. In this study, overexpressed proteins in OSMF, OSMF transformed into oral squamous cell carcinoma (OSCC) and normal tissues were evaluated by proteomic analysis using two-dimensional electrophoresis (2DE) and mass spectrometry, which revealed 23 upregulated proteins. Validation was done using immunohistochemistry for three secretory proteins, namely 14-3-3ε (n = 130), carbonic anhydrase 1 (CA 1) (n = 125) and heat shock protein 70 (HSP 70) (n = 117), which showed significant overexpression in OSMF, OSCC compared to normal. The present study is the first of its kind in India to the best of our knowledge, assessing the altered expression of proteins in OSMF and OSMF which has undergone malignant transformation, obtaining a better knowledge of the molecular pathways involved in the disease progression. The current study shows that the biomarkers studied can be potentially useful for risk stratification of OSMF to OSCC serving as novel targets for therapeutic intervention. Clinical validation of the targets can further pave way for precision medicine to improve the quality of life in OSMF patients.

Immunohistochemical Biomarkers in Oral Submucous Fibrosis - A Scoping Review

INTRODUCTION

This scoping review was done to study the immunohistochemical biomarkers involved in pathogenesis and malignant transformation (MT) of oral submucous fibrosis (OSF), in literature published from 2010 to 2021.

METHOD

The protocol was adapted from the Joanna Briggs Institute Reviewer's Manual (2017, and reported according to the PRISMA guidelines for Scoping Reviews (PRISMA-ScR).

RESULTS

Eighty-six studies included in this review reported 84 immunohistochemical (IHC) biomarkers in OSF: 9 epithelial markers, 29 connective tissue markers, 22 proliferative markers, and 24 other biomarkers that are transcription factors, cancer stem cell markers, cell signaling markers, proteins, and enzymes. The commonly reported IHC biomarkers were alpha-smooth muscle actin (α-SMA) and E-cadherin (7 articles each) followed by vascular endothelial growth factor (VEGF) and CD34 (6 articles each), p53, p63 and Ki67 (5 articles each). α-SMA, Ki67, CD105, and hTERT were significantly increased in oral squamous cell carcinoma arising in a background of OSF (OSCC-OSF) compared to OSF and normal subjects.

CONCLUSION

The identified surrogate IHC biomarkers reported in OSF in this scoping review require validation with long-term prospective studies to facilitate early diagnosis, for use in risk assessment, and plan appropriate treatment for OSF in clinical practice.

Pathological investigations and correlation research of microfibrillar-associated protein 4 and tropoelastin in oral submucous fibrosis

Background

Oral submucous fibrosis (OSF), distinguished by abnormal collagen deposition, is a potentially malignant disorder with 4.2% (95% CI 2.7–5.6%) of malignant transformation and rising global prevalence. However, the precise pathogenesis and effective treatment remain elusive and controversial despite the abundance of literature on this topic. Therefore, it is crucial to explore the clinicopathological characteristics and potential markers for the diagnosis and prognosis of OSF. The objective of this study was to evaluate the influence and correlation of Microfibrillar-associated protein 4 (MFAP4) and tropoelastin (TE) in the development of OSF patients.

Material and methods

Clinicopathological factors, hematoxylin–eosin (HE) and Masson trichome staining, immunohistochemical characteristics and the correlation between MFAP4 and TE were recorded and compared among different stages of OSF progression among cases (n = 60) and controls (n = 10). Student's t test, ANOVA analysis, and the chi-square test were performed to compare the categorical variables for clinicopathological characteristics and the expression level of MFAP4 and TE between the fibrotic and normal tissues. Correlation analysis of MFAP4 and TE was performed using Pearson's correlation test and linear regression.

Results

MFAP4 and TE proteins are upregulated and increased gradually in patients with varying stages of OSF, relative to the control group. Furthermore, statistical analyses revealed that the expression level of MFAP4 was positively associated with TE, with a Pearson correlation coefficient of 0.3781 (p = 0.0048). Clinically, we found that OSF affected more males than females, with a ratio of 29:1. The age range was 16–60 years, and the mean age was 36.25 ± 10.25 years. In patients younger than 40 years, the positive expression rate of MFAP4 and TE was higher than in those over 40 years. All OSF cases had chewed areca nut, with 51.67% smoking tobacco.

Conclusions

Our study elucidates that the accumulation of MFAP4 and TE proteins may play a vital role in the occurrence and development of OSF and may be promising candidate moleculars for prevention, diagnosis, and treatment strategies for OSF in the future.

A contemporary narrative review to guide molecular epidemiology of oral submucous fibrosis

Oral submucous Fibrosis (OSMF) is a chronic disease that mainly affects the upper part of the aerodigestive tract. Areca nut and betel quid chewing has been established as the most significant causative factor for this condition. While OSMF is a predominantly Asian disease, the migrant populations from the region have taken the disease across the globe. Additionally, areca nut is now easily accessible in flavors and aggressively marketed. Many research activities have been undertaken for decades to understand the etiopathogenesis and risk factors of OSMF. Although OSMF is a slowly progressing disease, it has the potential to transform to an oral malignancy. This article is an attempt to review the literature and provide an update on its prevalence, etiopthogenesis and its diagnosis. We also highlight certain clinical, histopathological and molecular features that aid in the diagnosis and prognostication of OSMF, highlighting the importance of identifying the possibly high risk OSMF that is prone to malignant transformation. Using this information, future directions can be developed to include treatmentof OSMF through a dynamic gene-specific approach.

[Expression of cyclophilin A in oral squamous cell carcinoma and its effect on cell proliferation and invasion]

OBJECTIVES

To investigate the expression of cyclophilin A (CyPA) in oral squamous cell carcinoma (OSCC) and explore the effect of downregulating the expression of CyPA gene on the proliferation and invasion of SCC-25 cells.

METHODS

A total of 77 cases of patients with OSCC were selected. The expression levels of CyPA proteins in OSCC and adjacent normal tissues were evaluated. SCC-25 cells were cultured and divided into the CyPA interference sequence group, negative control group, and blank group. The expression levels of CyPA mRNA and protein in cells were detected by using real-time fluorescent quantitative polymerase chain reaction and Western blot, respectively. Cell proliferation was detected by using methyl thiazolyl tetrazolium and plate colony formation assays. Cell invasion was detected by using Transwell assay.

RESULTS

The positive expression rate of CyPA protein in OSCC tissues was 76.62%, which was higher than that in adjacent tissues (P<0.05). The positive expression rate of CyPA protein in TNM stage T₃+T₄, clinical stage Ⅲ+Ⅳ, moderately or poorly differentiated lymph node metastasis was increased (P<0.05). Compared with the negative control and blank groups, the CyPA interference sequence group had decreased relative expression levels of CyPA mRNA and protein (P<0.05); optical density va-lues of cells at 24, 48, 72, and 96 h (P<0.05); and number of cell colonies and invasive cells (P<0.05).

CONCLUSIONS

The CyPA protein is highly expressed in OSCC tissues, and the downregulation of CyPA gene expression in SCC-25 cells can reduce cell proliferation and inhibit cell invasion.

FGF8 induces epithelial-mesenchymal transition and promotes metastasis in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is one of the most common cancers worldwide, and with 354 864 new cases each year. Cancer metastasis, recurrence, and drug resistance are the main causes to cripples and deaths of OSCC patients. As potent growth factors, fibroblast growth factors (FGFs) are frequently susceptible to being hijacked by cancer cells. In this study, we show that FGF8 is upregulated in OSCC tissues and high FGF8 expression is related with a set of clinicopathologic parameters, including age, drinking, and survival time. FGF8 treatment enhances the invasive capability of OSCC cells. Lentivirus-based FGF8 expression promotes OSCC metastasis in a mouse lung metastasis model. Further, mechanistic study demonstrates that FGF8 induces epithelial-mesenchymal transition (EMT) in OSCC cells. These results highlight a pro-metastatic function of FGF8, and underscore the role of FGF8 in OSCC development.

Oral Submucous Fibrosis: A Review on Biomarkers, Pathogenic Mechanisms, and Treatments

Oral submucous fibrosis (OSF) is a collagen deposition disorder that affects a patient’s oral function and quality of life. It may also potentially transform into malignancy. This review summarizes the risk factors, pathogenic mechanisms, and treatments of OSF based on clinical and bio-molecular evidence. Betel nut chewing is a major risk factor that causes OSF in Asia. However, no direct evidence of arecoline-induced carcinogenesis has been found in animal models. Despite identification of numerous biomarkers of OSF lesions and conducting trials with different drug combinations, clinicians still adopt conservative treatments that primarily focus on relieving the symptoms of OSF. Treatments focus on reducing inflammation and improving mouth opening to improve a patient’s quality of life. In conclusion, high-quality clinical studies are needed to aid clinicians in developing and applying molecular biomarkers as well as standard treatment guidelines.

Oral Submucous Fibrosis: A Review on Etiopathogenesis, Diagnosis, and Therapy

Oral submucous fibrosis (OSF) is characterized by abnormal collagen deposition. It is a precancerous disorder and transforms into a malignant tumor in 1.5–15% of all cases. Symptoms include submucous fibrosis, ulceration, xerostomia, a burning sensation, and restricted mouth opening. All of these greatly interfere with patient quality of life. The present review introduces OSF from a molecular perspective and summarizes what is known about its underlying mechanisms, diagnostic biomarkers, and therapeutic interventions. In addition to the aggressive treatment of OSF, its prevention is also important. Future research should, therefore, focus on improving the oral health literacy of the patients susceptible to OSF.

Positive Correlation between Activated CypA/CD147 Signaling and MMP-9 Expression in Mice Inflammatory Periapical Lesion

Aim

Cyclophilin A (CypA)/CD147 signaling plays critical roles in the regulation of inflammation and bone metabolism. This study aimed to investigate the participation of CypA/CD147 in mice periapical lesions progression and its relationship with bone resorption.

Methodology

Periapical lesions were induced by pulp exposure in the first lower molars of 40 C57BL/6J mice. The mice were sacrificed on days 0, 7, 14, 21, 28, 35, 42, and 49. Mandibles were harvested for X-ray imaging, microcomputed tomography scanning, histologic observation, immunohistochemistry, enzyme histochemistry, and double immunofluorescence analysis. Western blot was employed to further detect the related molecular signaling pathways in LPS-stimulated RAW 264.7 cells treated with CypA inhibitor.

Results

The volume and area of the periapical lesions increased from day 0 to day 35 and remained comparably stable until day 49. Immunohistochemistry demonstrated that the CypA expression levels also increased from day 0 to day 35 and decreased until day 49, similar to CD147 expression (R² = 0.4423, P < 0.05), osteoclast number (R² = 0.5101, P < 0.01), and the expression of osteoclastogenesis-related matrix metalloproteinase 9 (MMP-9) (R² = 0.4715, P < 0.05). Serial sections further confirmed the colocalization of CypA and CD147 on osteoclasts with immunohistochemistry. And the distribution of CypA-positive or CD147-positive cells was positively correlated with the dynamics of MMP-9-positive cells by using immunofluorescence analysis. Furthermore, CD147 and MMP-9 expression in RAW 264.7 cells were both downregulated with CypA inhibitor treatment (P < 0.05).

Conclusions

The present study reveals the positive correlation of CypA/CD147 signaling and osteoclast-related MMP-9 expression in mice inflammatory periapical lesions progression. Therefore, intervention of CypA/CD147 signaling could probably provide a potential therapeutic target for attenuating inflammatory bone resorption.