Investigation of trefoil factor expression in saliva and oral mucosal tissues of patients with oral squamous cell carcinoma

Shaping the future of oral cancer diagnosis: advances in salivary proteomics

INTRODUCTION

Saliva has gained increasing attention in the quest for disease biomarkers. Because it is a biological fluid that can be collected is an easy, painless, and safe way, it has been increasingly studied for the identification of oral cancer biomarkers. This is particularly important because oral cancer is often diagnosed at late stages with a poor prognosis.

AREAS COVERED

The review addresses the evolution of the experimental approaches used in salivary proteomics studies of oral cancer over the years and outlines advantages and pitfalls related to each one. In addition, examines the current landscape of oral cancer biomarker discovery and translation focusing on salivary proteomic studies. This discussion is based on an extensive literature search (PubMed, Scopus and Google Scholar).

EXPERT OPINION

The introduction of mass spectrometry has revolutionized the study of salivary proteomics. In the future, the focus will be on refining existing methods and introducing powerful experimental techniques such as mass spectrometry with selected reaction monitoring, which, despite their effectiveness, are still underutilized due to their high cost. In addition, conducting studies with larger cohorts and establishing standardized protocols for salivary proteomics are key challenges that need to be addressed in the coming years.

Salivary trefoil factor family peptide 3 (TFF3) and flow rate in persons with and without obstructive sleep apnea: A preliminary study

OBJECTIVES

Obstructive sleep apnea (OSA) is one of the most common chronic diseases. Trefoil factor family 3 (TFF3) peptides are secreted by major and minor salivary glands and may be involved in the pathogenesis of OSA. This study aimed to evaluate salivary TFF3 and flow rate between those with and without OSA.

MATERIAL AND METHODS

This was a prospective experimental study that enrolled patients with OSA and non-OSA. Total unstimulated saliva was collected, the salivary flow rate was measured, and the TFF3 level was analyzed by using a modified sandwich enzyme-linked immunosorbent assay. Baseline characteristics, TFF3 level, and salivary flow rate were compared between both groups. Factors associated with the TFF3 level and flow rate were computed by using multivariate linear regression analysis.

RESULTS

Twenty-eight participants were recruited in the study: 20 patients with OSA (71.42%) and 8 non-OSA as control. The TFF3 and salivary flow rates between both groups of non-OSA versus OSA were comparable (TFF3 non-OSA 61.06 vs. OSA 96.00 ng/mg; p = .276 and flow rate non-OSA 0.40 vs. OSA 0.35 mL/min; p = .320). Factors associated with the TFF3 level were neck circumference with a negative coefficient of -16.419 (p =  .042). For the salivary flow rate, only age was a significant factor with the coefficient of -0.013 (p = .044).

CONCLUSIONS

TFF3 and salivary flow rate were comparable between patients with OSA and non-OSA. The factor associated with TFF3 level was neck circumference, while age was negatively associated with the salivary flow rate in patients with OSA.

Salivary Trefoil Factor Family (TFF) Peptides and Their Roles in Oral and Esophageal Protection: Therapeutic Potential

Human saliva is a complex body fluid with more than 3000 different identified proteins. Besides rheological and lubricating properties, saliva supports wound healing and acts as an antimicrobial barrier. TFF peptides are secreted from the mucous acini of the major and minor salivary glands and are typical constituents of normal saliva; TFF3 being the predominant peptide compared with TFF1 and TFF2. Only TFF3 is easily detectable by Western blotting. It occurs in two forms, a disulfide-linked homodimer (Mr: 13k) and a high-molecular-mass heterodimer with IgG Fc binding protein (FCGBP). TFF peptides are secretory lectins known for their protective effects in mucous epithelia; the TFF3 dimer probably has wound-healing properties due to its weak motogenic effect. There are multiple indications that FCGBP and TFF3-FCGBP play a key role in the innate immune defense of mucous epithelia. In addition, homodimeric TFF3 interacts in vitro with the salivary agglutinin DMBT1^gp340. Here, the protective roles of TFF peptides, FCGBP, and DMBT1^gp340 in saliva are discussed. TFF peptides are also used to reduce radiotherapy- or chemotherapy-induced oral mucositis. Thus, TFF peptides, FCGBP, and DMBT1^gp340 are promising candidates for better formulations of artificial saliva, particularly improving wound healing and antimicrobial effects even in the esophagus.

The trefoil factor family 1 (TFF-1) and 3 (TFF-3) are upregulated in the saliva, gingival crevicular fluid and serum of periodontitis patients

OBJECTIVE

This study aimed to investigate the levels of trefoil factor family (TFF)-1, TFF-3 and interleukin (IL)-1β in gingival crevicular fluid (GCF), saliva and serum of patients with gingivitis, stage 3 periodontitis and healthy individuals.

MATERIALS AND METHODS

A total of 100 individuals consisting of 25 periodontally healthy, 25 gingivitis and 50 stage 3 periodontitis, were enrolled in the study. Clinical periodontal examinations were recorded and GCF, saliva and serum samples were obtained. TFF-1, TFF-3 and IL-1β were measured by ELISA.

RESULTS

TFF-1 and TFF-3 levels in both GCF, saliva and serum were higher in periodontitis patients than healthy controls (p < .001) and gingivitis group (p < .01). The levels of these peptides in all biofluids were similar between gingivitis and healthy control groups (p > .05). GCF, saliva and serum IL-1β levels were also higher in periodontitis patients than the controls (p < .01). Periodontitis patients had elevated GCF and saliva IL-β levels than gingivitis group (p < .001).

CONCLUSION

Elevated TFF-1 and TFF-3 levels both locally and systemically in periodontitis in parallel to increased IL-1β levels might suggest that these peptides are involved in host response during the periodontal tissue destruction.

Functional Specialization of Human Salivary Glands and Origins of Proteins Intrinsic to Human Saliva

Salivary proteins are essential for maintaining health in the oral cavity and proximal digestive tract, and they serve as potential diagnostic markers for monitoring human health and disease. However, their precise organ origins remain unclear. Through transcriptomic analysis of major adult and fetal salivary glands and integration with the saliva proteome, the blood plasma proteome, and transcriptomes of 28+ organs, we link human saliva proteins to their source, identify salivary-gland-specific genes, and uncover fetal- and adult-specific gene repertoires. Our results also provide insights into the degree of gene retention during gland maturation and suggest that functional diversity among adult gland types is driven by specific dosage combinations of hundreds of transcriptional regulators rather than by a few gland-specific factors. Finally, we demonstrate the heterogeneity of the human acinar cell lineage. Our results pave the way for future investigations into glandular biology and pathology, as well as saliva's use as a diagnostic fluid.

Human Synovia Contains Trefoil Factor Family (TFF) Peptides 1-3 Although Synovial Membrane Only Produces TFF3: Implications in Osteoarthritis and Rheumatoid Arthritis

Objective: Trefoil factor family peptide 3 (TFF3) has been shown to support catabolic functions in cases of osteoarthritis (OA). As in joint physiology and diseases such as OA, the synovial membrane (SM) of the joint capsule also plays a central role. We analyze the ability of SM to produce TFF compare healthy SM and its secretion product synovial fluid (SF) with SM and SF from patients suffering from OA or rheumatoid arthritis (RA). Methods: Real-time PCR and ELISA were used to measure the expression of TFFs in healthy SM and SM from patients suffering from OA or RA. For tissue localization, we investigated TFF1-3 in differently aged human SM of healthy donors by means of immunohistochemistry, real-time PCR and Western blot. Results: Only TFF3 but not TFF1 and -2 was expressed in SM from healthy donors as well as cases of OA or RA on protein and mRNA level. In contrast, all three TFFs were detected in all samples of SF on the protein level. No significant changes were observed for TFF1 at all. TFF2 was significantly upregulated in RA samples in comparison to OA samples. TFF3 protein was significantly downregulated in OA samples in comparison to healthy samples and cases of RA significantly upregulated compared to OA. In contrast, in SM TFF3 protein was not significantly regulated. Conclusion: The data demonstrate the production of TFF3 in SM. Unexpectedly, SF contains all three known TFF peptides. As neither articular cartilage nor SM produce TFF1 and TFF2, we speculate that these originate with high probability from blood serum.

Different Forms of TFF3 in the Human Saliva: Heterodimerization with IgG Fc Binding Protein (FCGBP)

The peptide TFF3 is a member of a family of secretory lectins, and is typically synthesized by mucous epithelia together with mucins. It is mainly released from intestinal goblet cells as a high-molecular mass heterodimer with IgG Fc binding protein (FCGBP). Herein, we investigated human saliva by fast protein liquid chromatography (FPLC) and proteomics and identified high- and low-molecular-mass forms of TFF3. Whereas the high-molecular-mass forms represent a heterodimer with FCGBP, the low-molecular-mass forms represent homodimeric TFF3 forms. Proteomic analysis also revealed a C-terminally truncated form of TFF3. We hypothesize that salivary TFF3-FCGBP might play a role in the innate immune defense of the oral cavity and that TFF3 might also bind to microbial glycans. The known interaction of TFF3 with the agglutinin DMBT-1, a typical constituent of human saliva, further supports this protective role.

Prolonged Suppressive Effects of Periodontitis on Salivary TFF3 Production

Objective As a follow-up to our previous study that demonstrated decreased salivary trefoil factor family 3 (TFF3) peptide levels in chronic periodontitis patients, this current study aimed to observe the effects of nonsurgical periodontal treatment on salivary TFF3 peptides in patients with periodontal diseases.

Materials and Methods Eighty-seven volunteers that comprised of 30 individuals with healthy periodontium, 31 with gingivitis, and 26 with chronic periodontitis were considered for the study. Prior to periodontal treatment, a general periodontal examination was performed along with collection of saliva samples from each volunteer. Nonsurgical periodontal treatments were provided to patients with gingivitis and periodontitis. Two weeks post-treatment, saliva samples were recollected, and the periodontal status was re-evaluated. Salivary TFF3 concentrations were measured by enzyme-linked immunosorbent assay.

Statistical Analysis Mann–Whitney U test was used when the investigated data were not normally distributed. Chi-squared test was used when dealing with categorical data. Kruskal–Wallis test with post-hoc corrections was used to compare data among the three investigated groups. Two-tailed p < 0.05 was considered as statistically significant.

Results Prior to the periodontal treatment, salivary TFF3 concentrations in patients with gingivitis and periodontitis were significantly lower than those with healthy periodontium. Two weeks post-treatment, increased levels of salivary TFF3 were observed in patients with gingivitis, whereas the concentrations decreased in patients with chronic periodontitis.

Conclusion This study demonstrated the effects of periodontal disease on the production of salivary TFF3 peptides. Interestingly, nonsurgical periodontal treatment also affected the recovery of salivary TFF3 peptides but varied in their outcomes between gingivitis and periodontitis patients.

TFF1 and TFF3 mRNAs Are Higher in Blood from Breast Cancer Patients with Metastatic Disease than Those without

Introduction

Breast cancer metastasis occurs when tumor cells dissociate from the primary tumor and migrate to distant organs through the peripheral bloodstream or lymphatic drainage. Circulating tumor cells (CTCs) originate from primary sites or metastases and circulate in the patients' bloodstream. Molecular assays for the detection and molecular characterization of CTCs can serve as a liquid biopsy and can represent an alternative to invasive biopsies as a source of tumor tissue in the metastatic patients.

Patients and Methods

We analyzed the presence of CTCs in the peripheral blood of 50 breast cancer patients by quantitative real-time reverse transcriptase polymerase chain reaction (RT-qPCR) to detect trefoil factor family (TFF) 1 and 3 genes.

Results

We found significant difference in the level of both TFF1 and TFF3 mRNA in the blood of nonmetastatic versus metastatic breast cancer patients (p= 0.001 and p= 0.038, respectively). TFF1 mRNA was detected at higher levels in 34.6% of metastatic breast cancer patients as compared to 0% of nonmetastatic (p= 0.002). As regards TFF3 mRNA, it was detected at higher levels in 46.2% of metastatic breast cancer patients as compared to 4% of nonmetastatic (p= 0.026). Moreover, we found that the high level of both TFF1 and TFF3 mRNA was related to estrogen status of the patients. The detection of high level of TFF1 mRNA in CTCs was associated with bone metastases (77.8%), while that of TFF3 was related to lymph node involvement (75%) and lung metastases (68.8%).

Conclusion

The combined measurement of both TFF1 and TFF3 mRNA level for differentiation of metastatic from nonmetastatic breast cancer gave 57.69% sensitivity and 83.3% specificity.

Production of Monoclonal Antibodies against Human Trefoil Factor 3 and Development of a Modified-Sandwich ELISA for Detection of Trefoil Factor 3 Homodimer in Saliva

Background

Human trefoil factor (TFF) peptides consist of three members: TFF1, TFF2 and TFF3. TFF3 is the most abundant TFF peptide in saliva. TFF3 homodimer was suggested to be involved in apoptosis inhibition and malignancy. Determination of TFF3 homodimer expression profiles in saliva may lead to new information about oral biology and diseases. The objective of this study was to generate monoclonal antibodies (mAbs) against TFF3 and apply the produced mAbs for the establishment of ELISA for quantification of dimeric TFF3 in saliva.

Results

With our modified hybridoma technique, three hybridoma clones producing anti-TFF3 mAbs having IgG isotype were generated. The mAbs were specific for TFF3 with no cross-reactivity to other TFFs. Using the generated mAbs, a modified-sandwich ELISA with high sensitivity for the quantification of dimeric TFF3 in saliva was developed. Using this ELISA, the amount of dimeric TFF3 in saliva could be measured.

Conclusions

A modified-sandwich ELISA for the quantification of TFF3 dimeric form was established. The established ELISA will be a valuable tool for facilitating the investigation of the physiological roles and the diagnostic values of TFF3 in oral diseases. The concept of this modified-sandwich ELISA may be applied for the determination of other homodimeric peptides of interest.

Obstructive sleep apnea and rhonchopathy are associated with downregulation of trefoil factor family peptide 3 (TFF3)-Implications of changes in oral mucus composition

Study objectives

Trefoil factor family (TFF) peptides belong to the family of mucin-associated peptides and are expressed in most mucosal surfaces. TFF peptides carry out functions such as proliferation and migration enhancement, anti-apoptosis, and wound healing. Moreover, TFFs are associated with mucins and interact with them as “linker peptides”, thereby influencing mucus viscosity.

To test the hypothesis that in rhonchopathy and obstructive sleep apnea (OSA) changes occur in the expression of TFF3 and -2 that could contribute to changes in mucus viscosity, leading to an increase in upper airway resistance during breathing.

Methods

RT-PCR, Western-blot, immunohistochemistry and ELISA were performed to detect and quantify TFF3 and -2 in uvula samples. In addition, 99 saliva samples from patients with mild, moderate or severe OSA, as well as samples from rhonchopathy patients and from healthy volunteers, were analyzed by ELISA.

Results

TFF3 was detected in all uvula samples. Immunohistochemistry revealed a subjectively decreasing antibody reactivity of the uvula epithelia with increasing disease severity. ELISA demonstrated significantly higher TFF3 saliva protein concentrations in the healthy control group compared to cases with rhonchopathy and OSA. Predisposing factors of OSA such as BMI or age showed no correlation with TFF3. No significant changes were observed with regard to TFF2.

Conclusions

The results suggest the involvement of TFF3 in the pathogenesis of rhonchopathy and OSA and lead to the hypothesis that reduction of TFF3 production by the epithelium and subepithelial mucous glands of the uvula contribute to an increase in breathing resistance due to a change in mucus organization.

Proteolytic effects of gingipains on trefoil factor family peptides

OBJECTIVES

The present study was aimed to determine whether trefoil factor family (TFF) peptides which were generally considered to be resistant to proteolysis could be digested by gingipains, a major proteinases produced by Porphyromonas gingivalis.

MATERIALS AND METHODS

Recombinant human TFF1, TFF2, and TFF3 peptides were used as substrates. Gingipains including arginine gingipain (RgpB) and lysine gingipain (Kgp) were used as enzymes. Trypsin was used as a control protease. Matrix-assisted laser desorption/ionization with time-of-flight / time-of-flight (MALDI-TOF/TOF) and liquid chromatography mass spectrometry (LC-MS) were used for analyzing peptide mass signals and amino acid sequences of digested TFF peptides.

RESULTS

MALDI-TOF/TOF analyses demonstrated that Kgp, RgpB, and trypsin were able to cleave TFF1 and TFF2 peptides, resulting in different patterns of digested fragments. However, impurity in recombinant TFF3 peptide substrates affected the interpretations of enzymatic reaction by MALDI-TOF/TOF. LC-MS analyses demonstrated that identified fragments of TFF1, TFF2, and TFF3 from digestion by gingipains were similar to those by trypsin.

CONCLUSIONS

Using MALDI-TOF/TOF and LC-MS, the present study provides new information that gingipains containing trypsin-like activities are able to digest TFF peptides.

CLINICAL RELEVANCE

The proteolytic effects of gingipains on TFF peptides may be responsible for reduction of salivary TFF peptides in chronic periodontitis patients. Further investigations to determine the pathological effects of gingipains on TFF peptides in saliva and periodontal tissues of patients with chronic periodontitis would be of interest.

Genome-wide gene expression profiling of tongue squamous cell carcinoma by RNA-seq

OBJECTIVE

Tongue squamous cell carcinoma (TSCC) is significantly more malignant than other type of oral squamous cell carcinoma (OSCC). In this study, we aimed to identify specific global gene expression signatures of TSCC to investigate the more invasive behavior of the deeply infiltrating cancer.

METHODS

Using RNA-seq technology, we detected gene expression of 20 TSCCs, 20 matched paratumor tissues, and 10 healthy normal mucosa tissues. Enrichment analysis of gene ontology (GO) and pathway was conducted using online tools DAVID for the dysregulated genes. Additionally, we performed the quantitative real-time RT-PCR (qRT-PCR) to validate the findings of RNA-Seq in 10 samples of TSCC, matched paratumor, and normal mucosa, respectively.

RESULTS

We detected 252 differentially expressed genes (DEGs) between TSCC and matched paratumor tissue, including 117 up-regulated and 135 down-regulated genes. For comparison between TSCC and normal mucosa, 234 DEGS were identified, consisting of 67 up-regulated and 167 down-regulated genes. For both two comparisons, GO categories of muscle contraction (GO: 0006936), epidermis development (GO: 0008544), epithelial cell differentiation (GO: 0030855), and keratinization (GO: 0031424) were commonly enriched. Altered gene expression affected some cancer-related pathways, such as tight junction. The qRT-PCR validation showed that gene expression patterns of FOLR1, NKX3-1, TFF3, PIGR, NEFL, MMP13, and HMGA2 were fully in concordance with RNA-Seq results.

CONCLUSION

Findings in this study demonstrated the genetic and molecular alterations associated with TSCC, providing new clues for understanding the molecular mechanisms of TSCC pathogenesis.

Diagnostic value evaluation of trefoil factors family 3 for the early detection of colorectal cancer

AIM

The purpose of this study was to evaluate the diagnostic value of trefoil factor family 3 (TFF3) for the early detection of colorectal cancer (CC).

METHODS

Serum TFF3 and carcino-embryonic antigen (CEA) were detected in 527 individuals, including 115 healthy control (HC), 198 colorectal adenoma (CA), and 214 CC individuals in the training group.

RESULTS

Serum TFF3 showed no significant correlation with age, gender, or tumor location but showed significant correlation with the tumor stage. Serum TFF3 in the CC group was significantly higher than in the HC or CA group. The AUC values of TFF3 for discriminating between HC and CC and between CA and CC were 0.930 (0.903, 0.958) and 0.834 (0.796, 0.873). A multivariate model combining TFF3 and CEA was built. Compared to TFF3 or CEA alone, the multivariate model showed significant improvement (P < 0.001). For discriminating between HC and CC, HC and early stage CC, HC and advanced stage CC, CA and CC, CA and early stage CC, and CA and advanced stage CC in the training group, the sensitivities were 92.99%, 91.46%, 93.18%, 73.83%, 76.83%, and 81.82%, and the specificities were 91.30%, 91.30%, 93.91%, 88.38%, 77.27%, and 88.38%, respectively. After validation, the sensitivities were 89.39%, 85.71%, 90.79%, 72.73%, 71.43%, and 78.95%, and the specificities were 87.85%, 87.85%, 2.52%, 87.85%, 80.77%, and 87.50%, respectively.

CONCLUSION

The multivariate diagnostic model that included TFF3 and CEA showed significant improvement over the conventional biomarker CEA and might provide a potential method for the early detection of CC.

Increased immunoexpression of trefoil factors in salivary gland tumors

OBJECTIVE

Very little is known about the role of trefoil factors (TFFs) in salivary gland tumors, and TFF immunoexpression has never been investigated in such tumors. The aim of this study was to evaluate TFF immunoexpression in benign and malignant salivary gland tumors.

MATERIALS AND METHODS

Benign (n = 25) and malignant (n = 25) salivary gland tumor specimens were included in this study, using mucocele (n = 25) specimens as a control group. Immunohistochemical staining was performed to evaluate the expression of TFFs (TFF1, TFF2, and TFF3) by semiquantitative means.

RESULTS

Expression of TFF1, TFF2, and TFF3 was significantly increased in benign (p = 0.001, p = 0.005, p < 0.001, respectively) and malignant (p < 0.001, p < 0.001, p < 0.001, respectively) groups as compared with the control group. Patterns of co-expression between TFF1/TFF2, TFF2/TFF3, and TFF1/TFF3 were different among the three groups.

CONCLUSIONS

The present study provided new information showing that all TFFs were significantly increased in benign and malignant salivary gland tumors, and overexpression of TFFs could be associated with neoplastic transformation in salivary gland tissues.

CLINICAL RELEVANCE

Overexpression of TFFs may be useful as biomarkers in terms of differential diagnosis between salivary gland tumors and other oral neoplasms for which clinical manifestations are indistinguishable.

Trefoils: An unexplored natural protective shield of oral cavity

The new mammalian growth factor peptide family consists of three peptides, TFF1, TFF2, and TFF3, which are secreted mainly from mucous epithelia with mucus gel. The predominant secretion of trefoil factor (TFF) occurs from gastric mucosal lining, small and large intestine, oral mucosal cells, and salivary glands. Research regarding trefoil factors is an immerging aspect in the dental field. The mucosal healing and restitution function describes about its novel role in case of chronic inflammatory conditions, but its expression from different tissue at different pathological condition shows its importance in immune response. At present, TFF expression has been detected from the severe periodontal diseased tissue samples. Future research from mild to moderate chronic periodontal diseased condition should be carried out to assess the protective response of TFF in gingival tissues. In future, assessment of TFF levels and its expression in oral mucosal tissues and oral secretions, such as saliva and gingival crevicular fluid, will provide a negative biomarker for chronic periodontal diseases and a novel therapeutic agent in oral mucosal healing.

Trefoil factor 3 as a novel biomarker to distinguish between adenocarcinoma and squamous cell carcinoma

In carcinoma, such as of the lung, the histological subtype is important to select an appropriate therapeutic strategy for patients. However, carcinomas with poor differentiation cannot always be distinguished on the basis of morphology alone nor on clinical findings. Hence, delineation of poorly differentiated adenocarcinoma and squamous cell carcinoma, the 2 most common epithelial-origin carcinomas, is pivotal for selection of optimum therapy. Herein, we explored the potential utility of trefoil factor 3 (TFF3) as a biomarker for primary lung adenocarcinoma and extrapulmonary adenocarcinomas derived from different organs. We observed that 90.9% of lung adenocarcinomas were TFF3-positive, whereas no expression of TFF3 was observed in squamous cell carcinomas. The subtype of lung carcinoma was confirmed by four established biomarkers, cytokeratin 7 and thyroid transcription factor 1 for adenocarcinoma and P63 and cytokeratin 5/6 for squamous cell carcinoma. Furthermore, expression of TFF3 mRNA was observed by quantitative PCR in all of 11 human lung adenocarcinoma cell lines and highly correlated with markers of the adenocarcinomatous lineage. In contrast, little or no expression of TFF3 was observed in 4 lung squamous cell carcinoma cell lines. By use of forced expression, or siRNA-mediated depletion of TFF3, we determined that TFF3 appeared to maintain rather than promote glandular differentiation of lung carcinoma cells. In addition, TFF3 expression was also determined in adenocarcinomas from colorectum, stomach, cervix, esophagus, and larynx. Among all these extrapulmonary carcinomas, 93.7% of adenocarcinomas exhibited TFF3 positivity, whereas only 2.9% of squamous cell carcinomas were TFF3-positive. Totally, 92.9% of both pulmonary and extrapulmonary adenocarcinomas exhibited TFF3 positivity, whereas only 1.5% of squamous cell carcinomas were TFF3-positive. In conclusion, TFF3 is preferentially expressed in adenocarcinoma and may function as an additional biomarker for distinguishing adenocarcinoma from squamous cell carcinoma.

Trefoil factor family peptides TFF1 and TFF3 in the nervous tissues of developing mouse embryo

Trefoil factor family peptides (TFF1, TFF2, and TFF3) are predominantly found in mucous epithelia of various organs. However, they have also been reported in the nervous tissue, particularly mouse, rat, porcine, and human brain. The aim of this research was to determine the presence of TFF1 and TFF3 in the nervous system of developing mouse embryo. Mouse embryos, at the stages E15 to E17 were isolated, fixed in 4% paraformaldehyde and embedded in paraffin blocks. Sagittal 6µm sections were made, processed for immunohistochemistry, and incubated with anti-TFF1 or anti-TFF3 primary polyclonal rabbit antibodies. Labeled streptavidin-biotin method was used for TFF detection. TFF1 and 3 were found in the cytoplasm of ganglion cell somata, while TFF3 staining was also visible in the cytoplasm of neurons in different areas and nuclei of brain and medulla oblongata. Neurons in the gray matter of spinal cord were also TFF1 and TFF3 positive, and signal for both peptides was found in the choroid plexus. TFF peptides might be involved in the complex processes of nervous system development and differentiation and brain plasticity.

Brief communication (Original). Trefoil factor expression by immunohistochemistry in patients with oral lichen planus

Background: Oral lichen planus (OLP) is a chronic immune-mediated inflammatory disease that usually causes oral mucosal damage. OLP has been considered to be a potentially malignant disorder associated with an increased risk for oral cancer. Trefoil factors (TFFs) are mainly synthesized by mucin-producing epithelial cells. Expression of TFFs in oral epithelia is thought to be an essential factor in protection against oral mucosal damage. However, very little is known about the connection between tissue damage of oral mucosa in OLP patients and expression of TFFs.

Objectives: To determine levels of TFF expression in oral mucosa from patients with OLP.

Methods: Tissue samples were collected from 35 patients with normal oral mucosa (controls) and 35 patients with OLP. An immunohistochemical method was used to determine the expression of the 3 TFFs (TFF1, 2, and 3) in mucosal tissues of the oral cavity.

Results:TFF2 and TFF3 expression in oral epithelia were significantly decreased in OLP patients (Mann- Whitney U test; P = 0.006, and P = 0.002, respectively). There were no significant differences in TFF1 expression between OLP patients and control subjects.

Conclusion: The present study demonstrated reduced expression of TFF2 and TFF3 in oral epithelia of OLP patients. These outcomes support our previous observations that chronic inflammation may play a major role in downregulation of TFF expression, which may be associated with oral mucosal damage in OLP patients.

Salivary level of interleukin-8 in oral precancer and oral squamous cell carcinoma

BACKGROUND

Interleukin 8 (IL-8) is a pro-angiogenic, pro-inflammatory mediator that belongs to the family of chemokines. Due to its pro-angiogenic characteristic, it may play a vital role in tumour angiogenesis and progression.

OBJECTIVES

This study was designed to estimate the levels of salivary IL-8 in oral precancer and oral squamous cell carcinoma (OSCC) patients and compare them with healthy controls. The aim was to evaluate its efficacy as a potential biomarker for these diseases.

MATERIALS AND METHODS

Each group comprised 25 individuals. The salivary IL-8 levels were determined by enzyme-linked immunosorbent assay.

RESULTS

The levels of salivary IL-8 were found to be significantly elevated in patients with OSCC as compared to the precancer group (p < 0.0001) and healthy controls (p < 0.0001). However, the difference in salivary IL-8 concentrations among the precancer group and controls was statistically non-significant (p = 0.738).

CONCLUSIONS

Our results suggested that salivary IL-8 can be utilised as a potential biomarker for OSCC. Salivary IL-8 was found to be non-conclusive for oral premalignancy in this preliminary study. Hence, its possible role in transition from premalignancy to malignancy needs further research with larger sample sizes.

CLINICAL RELEVANCE

Saliva as a diagnostic biofluid offers a number of advantages over blood-based testing. The role of IL-8 in oral cancer if validated further by future research can provide an easy diagnostic test as well as a prognostic indicator for patients undergoing treatment. Therefore, if it's role in tumourigenesis can be sufficiently assessed, it could open up new avenues to find out novel treatment modalities for oral cancer.