Trefoil factors: from ulceration to neoplasia

A Trefoil factor 3-Lingo2 axis restrains proliferative expansion of type-1 T helper cells during GI nematode infection

Host defense at the mucosal interface requires collaborative interactions between diverse cell lineages. Epithelial cells damaged by microbial invaders release reparative proteins such as the Trefoil factor family (TFF) peptides that functionally restore barrier integrity. However, whether TFF peptides and their receptors also serve instructive roles for immune cell function during infection is incompletely understood. Here, we demonstrate that the intestinal trefoil factor, TFF3, restrains (T cell helper) TH1 cell proliferation and promotes host-protective type 2 immunity against the gastrointestinal parasitic nematode Trichuris muris. Accordingly, T cell-specific deletion of the TFF3 receptor, leucine-rich repeat and immunoglobulin containing nogo receptor 2 (LINGO2), impairs TH2 cell commitment, allows proliferative expansion of interferon (IFN)g+ cluster of differentiation (CD)4+ TH1 cells and blocks normal worm expulsion through an IFNg-dependent mechanism. This study indicates that TFF3, in addition to its known tissue reparative functions, drives anti-helminth immunity by controlling the balance between TH1/TH2 subsets.

The Association of Trefoil Factors with Gastric Cancer and Premalignant Lesions: A Cross-sectional Population-based Cohort Study

BACKGROUND

A lack of research on the association of trefoil factors (TFFs) with gastric cancer (GC) and premalignant lesions (PMLs) in the general populations is an important obstacle to the application of TFFs for GC screening. We aimed to analyze the association of TFFs with GC and PMLs in a general population.

METHODS

We evaluated 3,986 adults residing in Wuwei, China. We collected baseline characteristics and GC risk factors, including TFFs, endoscopic diagnosis, and pathological information. Three logistic regression models were generated to analyze the association between TFFs and GC, as well as PMLs. Adjusted odds ratio (OR) and 95% confidence intervals (95% CI) were calculated to determine the strength of association.

RESULTS

Compared with pepsinogen (PG) and anti-Helicobacter pylori immunoglobulin G antibody (Hp-IgG), TFFs had significant association with GC and PMLs after adjusting for biomarkers and risk factors (P < 0.05). The ORs [95% CI] for TFF1 (1.67 [1.27-2.20]), TFF2 (2.66 [2.01-3.51]), and TFF3 (1.32 [1.00-1.74]) were larger than the ORs for PGI (0.79 [0.61-1.03]), PGI/II (1.00 [0.76-1.31]) and Hp-IgG (0.99 [0.73-1.35]) in the GC group. In intestinal metaplasia (IM) group, not only the TFF3 serum level was the highest, but also the OR (1.92 [1.64-2.25]) was the highest.

CONCLUSIONS

Trefoil factor were associated with risk of GC and PMLs.

IMPACT

Serum TFFs can improve the screening of high-risk populations for GC.

Trefoil Factor Family (TFF) Peptides and Their Links to Inflammation: A Re-evaluation and New Medical Perspectives

Trefoil factor family peptides (TFF1, TFF2, TFF3), together with mucins, are typical exocrine products of mucous epithelia. Here, they act as a gastric tumor suppressor (TFF1) or they play different roles in mucosal innate immune defense (TFF2, TFF3). Minute amounts are also secreted as endocrine, e.g., by the immune and central nervous systems. As a hallmark, TFF peptides have different lectin activities, best characterized for TFF2, but also TFF1. Pathologically, ectopic expression occurs during inflammation and in various tumors. In this review, the role of TFF peptides during inflammation is discussed on two levels. On the one hand, the expression of TFF1-3 is regulated by inflammatory signals in different ways (upstream links). On the other hand, TFF peptides influence inflammatory processes (downstream links). The latter are recognized best in various Tff-deficient mice, which have completely different phenotypes. In particular, TFF2 is secreted by myeloid cells (e.g., macrophages) and lymphocytes (e.g., memory T cells), where it modulates immune reactions triggering inflammation. As a new concept, in addition to lectin-triggered activation, a hypothetical lectin-triggered inhibition of glycosylated transmembrane receptors by TFF peptides is discussed. Thus, TFFs are promising players in the field of glycoimmunology, such as galectins and C-type lectins.

Trefoil Factor Family (TFF) Peptides and Their Diverse Molecular Functions in Mucus Barrier Protection and More: Changing the Paradigm

Trefoil factor family peptides (TFF1, TFF2, TFF3) are typically co-secreted together with mucins. Tff1 represents a gastric tumor suppressor gene in mice. TFFs are also synthesized in minute amounts in the immune and central nervous systems. In mucous epithelia, they support rapid repair by enhancing cell migration ("restitution") via their weak chemotactic and anti-apoptotic effects. For a long time, as a paradigm, this was considered as their major biological function. Within recent years, the formation of disulfide-linked heterodimers was documented for TFF1 and TFF3, e.g., with gastrokine-2 and IgG Fc binding protein (FCGBP). Furthermore, lectin activities were recognized as enabling binding to a lipopolysaccharide of Helicobacter pylori (TFF1, TFF3) or to a carbohydrate moiety of the mucin MUC6 (TFF2). Only recently, gastric TFF1 was demonstrated to occur predominantly in monomeric forms with an unusual free thiol group. Thus, a new picture emerged, pointing to diverse molecular functions for TFFs. Monomeric TFF1 might protect the gastric mucosa as a scavenger for extracellular reactive oxygen/nitrogen species. Whereas, the TFF2/MUC6 complex stabilizes the inner layer of the gastric mucus. In contrast, the TFF3-FCGBP heterodimer (and also TFF1-FCGBP) are likely part of the innate immune defense of mucous epithelia, preventing the infiltration of microorganisms.

TFF3 and TFF1 expression levels are elevated in colorectal cancer and promote the malignant behavior of colon cancer by activating the EMT process

Reports on the roles of the secreted trefoil factor (TFF)1 and 3 in colorectal cancer (CRC) and their underlying mechanisms of action in tumorigenesis are not common and are controversial. In the present study, the mRNA expression and promoter methylation of TFF1 and TFF3 in cancer and adjacent normal tissues were investigated, and their association with other clinical factors and patient prognosis were evaluated. Moreover, the association between TFF3 and epithelial mesenchymal transition (EMT) was explored by overexpressing or inhibiting TFF3 expression. The results revealed that the mRNA level of TFF1 and TFF3 in the cancer tissues was significantly higher than that in the matched adjacent normal tissues (P=0.034 and P=0.007, respectively), and a higher expression of TFF3, but not TFF1, was predominantly associated with clinicopathological factors and a poorer prognosis. No correlation was observed between promoter methylation and the expression of TFF1 or TFF3. The overexpression of TFF3 promoted the proliferation, migration and invasiveness of HT29 cells, and induced an increase in the expression of Twist1, Snail and Vimentin, while causing a decrease in E-cadherin expression. On the contrary, the knockdown of TFF3 resulted in opposite effects in the LoVo cells. On the whole, the findings of this study indicate that TFF3 may be a promising new factor for the estimation of the survival of patients with CRC, and may promote the malignant progression of CRC by activating the EMT process. Therefore, TFF3 may be a future potential therapeutic target for CRC.

Trefoil factor 3 knock-down prevents autophagy-related gene 12 elevation in colon adenocarcinoma

Colon cancer, which is considered a common gastrointestinal cancer, has been the third leading cause of cancer mortality in the United States. Colon cancer has various histological sub-types and 90% of them are adenocarcinoma. In recent years, autophagy, the process by which cells are self-cannibalized, has been implicated in pathophysiology of various diseases including colon adenocarcinoma and thus, has become a strong research focus. This has also been true for trefoil factor 3 (TFF3). TFF3 is a small secreted peptide that is present in almost all mucin-secreting tissues, it is most abundant in goblet cells of the gastrointestinal tract and expressed at high protein levels in colon cancer. The present study analyzed the expression of TFF3 and autophagy-related gene ATG12 in cancerous and normal tissue samples collected from patients with colon adenocarcinoma. The expression of both proteins was shown to be increased in cancerous as compared to adjacent non-cancerous tissues. Furthermore, these proteins were shown to be positively correlated using the Pearson's Correlation test in cancerous tissues. Finally, TFF3 was shown to regulate ATG12 in human colon adenocarcinoma cells in vitro. Thus, the data presented here suggest that both TFF3 and ATG12 may be promising potential therapeutic targets to develop novel treatment strategies for patients with colon adenocarcinoma.

Differential Expression of TFF Genes and Proteins in Breast Tumors

SUMMARY – The objective of this study was to determine differential expression of TFF1, TFF2 and TFF3 genes and proteins in breast tumor subtypes. In addition, we investigated the correlation between TFF genes within tumor subgroups, and TFF genes with clinical and pathologic characteristics of the tumor. Study group included 122 patients with surgically removed breast tumors. Samples were investigated using qRT-PCR and immunohistochemistry. TFF1 and TFF3 genes and proteins were expressed in breast tumors, while the levels of TFF2 gene and protein expression were very low or undetectable. TFF1 was significantly more expressed in benign tumors, while TFF3 was more expressed in malignant tumors. Gene and protein expression of both TFF1 and TFF3 was greater in lymph node-negative tumors, hormone positive tumors, tumors with moderate levels of Ki67 expression, and in grade II tumors. A strong positive correlation was found between TFF1 and TFF3 genes, and the expression of both negatively correlated with Ki67 and the level of tumor histologic differentiation. Our results suggest that TFF1 and TFF3, but not TFF2, may have a role in breast tumor pathogenesis and could be used in the assessment of tumor differentiation and malignancy.

Localization of trefoil factor family peptide 3 (TFF3) in epithelial tissues originating from the three germ layers of developing mouse embryo

Trefoil factor family (TFF) peptides are involved in the maintenance of epithelial integrity and epithelial restitution. Mature epithelial tissues originate from different embryonic germ layers. The objective of this research was to explore the presence and localization of TFF3 peptide in mouse embryonic epithelia and to examine if the occurrence of TFF3 peptide is germ layer-dependent. Mouse embryos (14-18 days old) were fixed in 4% paraformaldehyde and embedded in paraffin. Immunohistochemistry was performed with affinity purified rabbit anti-TFF3 antibody, goat anti-rabbit biotinylated secondary antibody and streptavidin-horseradish peroxidase, followed by 3,3'-diaminobenzidine. TFF3 peptide was present in the gastric and intestinal mucosa, respiratory mucosa in the upper and lower airways, pancreas, kidney tubules, epidermis, and oral cavity. The presence and localization of TFF3 peptide was associated with the embryonic stage and tissue differentiation. TFF3 peptide distribution specific to the germ layers was not observed. The role of TFF3 peptide in cell migration and differentiation, immune response, and apoptosis might be associated with specific embryonic epithelial cells. TFF3 peptide may also be considered as a marker for mucosal maturation.

Histomorphometric Parameters of the Growth Plate and Trabecular Bone in Wild-Type and Trefoil Factor Family 3 (Tff3)-Deficient Mice Analyzed by Free and Open-Source Image Processing Software

Trefoil factor family 3 (Tff3) peptide is present during intrauterine endochondral ossification in mice, and its deficiency affects cancellous bone quality in secondary ossification centers of mouse tibiae. The aim of this study was to quantitatively analyze parameters describing the growth plate and primary ossification centers in tibiae of 1-month-old wild-type and Tff3 knock-out mice (n=5 per genotype) by using free and open-source software. Digital photographs of the growth plates and trabecular bone were processed by open-source computer programs GIMP and FIJI. Histomorphometric parameters were calculated using measurements made with FIJI. Tff3 knock-out mice had significantly smaller trabecular number and significantly larger trabecular separation. Trabecular bone volume, trabecular bone surface, and trabecular thickness showed no significant difference between the two groups. Although such histomorphological differences were found in the cancellous bone structure, no significant differences were found in the epiphyseal plate histomorphology. Tff3 peptide probably has an effect on the formation and quality of the cancellous bone in the primary ossification centers, but not through disrupting the epiphyseal plate morphology. This work emphasizes the benefits of using free and open-source programs for morphological studies in life sciences.

Expression of trefoil factors and TWIST1 in colorectal cancer and their correlation with metastatic potential and prognosis

AIM

To detect the expression of trefoil factors (TFFs) and TWIST1 in colorectal cancer (CRC) and analyze their correlation with metastasis and survival.

METHODS

This study examined the expression of TFF1, TFF3 and TWIST1 in a total of 75 tumor samples, 47 matched normal samples (15 cm from the lesion margin), 30 metastatic lymph nodes, and 10 liver metastatic cancer samples from patients with CRC. The relationship was then analyzed between the protein expression and different clinical records. TFF1, TFF3, TWIST1,E-cadherin, vimentin and β-catenin mRNA and protein expression levels were measured in colon cancer cell lines with different metastatic potentials (HIEC, HT29, SW620, and LoVo cells), and the correlation of the expression levels with epithelial-mesenchymal transition (EMT) was discussed.

RESULTS

It was found that 66.7% (50/75), 78.7% (59/75) and 54.7% (41/75) of tumor tissue samples exhibited positive staining for TFF1, TFF3 and TWIST1 and so did 27.3% (13/47), 100% (47/47) and 17% (8/47) of adjacent normal colorectal tissues. Compared with adjacent normal tissues, significant differences were found in the expression of all three proteins in different cancerous tissues (P < 0.05). Higher expression of TFF3 and TWIST1 was significantly correlated with lymph node metastasis (P = 0.034, P = 0.000), advanced stage (P = 0.031, P = 0.003), and poorer survival (P = 0.042 for the TFF3 group, P = 0.003 for the TWIST1 group). The expression of TFF3 and TWIST1 in cancer cell lines was higher than that in HIEC (a normal human intestinal epithelial cell line)(P < 0.05), and the expression intensity demonstrated a tendency to rise with increased metastatic potential both at the protein and mRNA levels. However, TFF1 expression demonstrated the opposite tendency. It was also observed that the expression of E-cadherin and β-catenin tended to decrease while that of vimentin, TWIST1 and Snail tended to rise with the increase in metastatic potential.

CONCLUSION

The expression of TFF3 and TWIST1 might be associated with the survival of patients with CRC after curative resection and might be pivotal predictors of disease progression. TFF3 may be correlated to the invasiveness of CRC.

Identification of genes differentially expressed in menstrual breakdown and repair

STUDY QUESTION

Does the changing molecular profile of the endometrium during menstruation correlate with the histological profile of menstruation.

SUMMARY ANSWER

We identified several genes not previously associated with menstruation; on Day 2 of menstruation (early-menstruation), processes related to inflammation are predominantly up-regulated and on Day 4 (late-menstruation), the endometrium is predominantly repairing and regenerating.

WHAT IS KNOWN ALREADY

Menstruation is induced by progesterone withdrawal at the end of the menstrual cycle and involves endometrial tissue breakdown, regeneration and repair. Perturbations in the regulation of menstruation may result in menstrual disorders including abnormal uterine bleeding.

STUDY DESIGN, SIZE DURATION

Endometrial samples were collected by Pipelle biopsy on Days 2 (n = 9), 3 (n = 9) or 4 (n = 6) of menstruation.

PARTICIPANTS/MATERIALS, SETTING, METHODS

RNA was extracted from endometrial biopsies and analysed by genome wide expression Illumina Sentrix Human HT12 arrays. Data were analysed using 'Remove Unwanted Variation-inverse (RUV-inv)'. Ingenuity pathway analysis (IPA) and the Database for Annotation, Visualization and Integrated Discovery (DAVID) v6.7 were used to identify canonical pathways, upstream regulators and functional gene clusters enriched between Days 2, 3 and 4 of menstruation. Selected individual genes were validated by quantitative PCR.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, 1753 genes were differentially expressed in one or more comparisons. Significant canonical pathways, gene clusters and upstream regulators enriched during menstrual bleeding included those associated with immune cell trafficking, inflammation, cell cycle regulation, extracellular remodelling and the complement and coagulation cascade. We provide the first evidence for a role for glutathione-mediated detoxification (glutathione-S-transferase mu 1 and 2; GSTM1 and GSTM2) during menstruation. The largest number of differentially expressed genes was between Days 2 and 4 of menstruation (n = 1176). We identified several genes not previously associated with menstruation including lipopolysaccharide binding protein, serpin peptidase inhibitor, clade B (ovalbumin), member 3 (SERPINB3) and -4 (SERPINB4), interleukin-17C (IL17C), V-set domain containing T-cell activation inhibitor 1 (VTCN1), proliferating cell nuclear antigen factor (KIAA0101/PAF), trefoil factor 3 (TFF3), laminin alpha 2 (LAMA2) and serine peptidase inhibitor, Kazal type 1 (SPINK1). Genes related to inflammatory processes were up-regulated on Day 2 (early-menstruation), and those associated with endometrial repair and regeneration were up-regulated on Day 4 (late-menstruation).

LIMITATIONS, REASONS FOR CAUTION

Participants presented with a variety of endometrial pathologies related to bleeding status and other menstrual characteristics. These variations may also have influenced the menstrual process.

WIDER IMPLICATIONS OF THE FINDINGS

The temporal molecular profile of menstruation presented in this study identifies a number of genes not previously associated with the menstrual process. Our findings provide valuable insight into the menstrual process and may present novel targets for therapeutic intervention in cases of endometrial dysfunction.

LARGE SCALE DATA

All microarray data have been deposited in the public data repository Gene Expression Omnibus (GSE86003).

STUDY FUNDING AND COMPETING INTERESTS

Funding for this work was provided by a National Health and Medical Research Council of Australia (NHMRC) Project Grant APP1008553 to M.H., P.R. and J.G. M.H. is supported by an NHMRC Practitioner Fellowship. P.P. is supported by a NHMRC Early Career Fellowship. The authors have no conflict of interest to declare.

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.

Trefoil factor family peptides – friends or foes?

Trefoil factor family (TFF) peptides are a group of molecules bearing a characteristic three-loop trefoil domain. They are mainly secreted in mucous epithelia together with mucins but are also synthesized in the nervous system. For many years, TFF peptides were only known for their wound healing and protective function, e.g. in epithelial protection and restitution. However, experimental evidence has emerged supporting a pivotal role of TFF peptides in oncogenic transformation, tumorigenesis and metastasis. Deregulated expression of TFF peptides at the gene and protein level is obviously implicated in numerous cancers, and opposing functions as oncogenes and tumor suppressors have been described. With regard to the regulation of TFF expression, epigenetic mechanisms as well as the involvement of various miRNAs are new, promising aspects in the field of cancer research. This review will summarize current knowledge about the expression and regulation of TFF peptides and the involvement of TFF peptides in tumor biology and cancerogenesis.

Trefoil Factor Expression in a Human Model of the Early Stages of Barrett's Esophagus

BACKGROUND

Trefoil proteins are believed to have an important role in mucosal protection and repair in the gastrointestinal tract. They are well recognized in Barrett's esophagus and considered a potential biomarker for the condition. Metaplasia occurring in the esophageal remnant after esophagectomy is a human model for the early stages of development of Barrett's esophagus.

AIMS

To assess expression of trefoil proteins in post-esophagectomy columnar epithelium and to use trefoils as a molecular tool to understand regenerative mucosa in the esophagus.

METHODS

Patients with columnar metaplasia in the esophageal remnant were recruited from a large esophago-gastric cancer center. Trefoil factor expression was determined using immunohistochemical techniques.

RESULTS

Samples were obtained from 37 patients. TFF1 and TFF2 were expressed by all samples in a similar pattern to that described in studies of sporadic Barrett's esophagus. TFF3 was less widely expressed and was significantly associated with time elapsed between surgery and endoscopy. Median time from surgery to endoscopy was 8.1 years for patients with TFF3 expression versus 3.4 years for those without (p = 0.004).

CONCLUSIONS

Widespread expression of trefoils in this environment suggests that these proteins have an important role in development of Barrett's metaplasia. TFF3 expression may be absent in the early stages of metaplasia and may represent more established columnar epithelium. Biopsy samples from post-esophagectomy patients provide a valuable resource to study the early stages of Barrett's esophagus.

Trefoil factor 3 (TFF3) enhances the oncogenic characteristics of prostate carcinoma cells and reduces sensitivity to ionising radiation

Trefoil factor 3 (TFF3) is a secreted protein which functions in mucosal repair of the gastrointestinal tract. This is achieved through the combined stimulation of cell migration and prevention of apoptosis and anoikis, thus facilitating repair. Deregulated TFF3 expression at the gene and protein level is implicated in numerous cancers. In prostate cancer TFF3 has previously been reported as a potential biomarker, overexpressed in a subset of primary and metastatic cases. Here we investigated the effect of increased TFF3 expression on prostate cancer cell behaviour. Oncomine analysis demonstrated that TFF3 mRNA expression was upregulated in prostate cancer compared to normal tissue. Forced-expression models were established in the prostate cancer cell lines, DU145 and PC3, by stable transfection of an expression vector containing the TFF3 cDNA. Forced expression of TFF3 significantly increased total cell number and cell viability, cell proliferation and cell survival. In addition, TFF3 enhanced anchorage independent growth, 3-dimensional colony formation, wound healing and cell migration compared to control transfected cell lines. We also observed reduced sensitivity to ionising radiation in stably transfected cell lines. In dose response experiments, forced expression of TFF3 significantly enhanced the regrowth of PC3 cells following ionising radiation compared with control transfected cells. In addition, TFF3 enhanced clonogenic survival of DU145 and PC3 cells. These studies indicate that targeting TFF3 for the treatment of prostate cancer warrants further investigation.

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.

TFF2 deficiency exacerbates weight loss and alters immune cell and cytokine profiles in DSS colitis, and this cannot be rescued by wild-type bone marrow

The trefoil factor TFF2 is a member of a tripartite family of small proteins that is produced by the stomach and the colon. Recombinant TFF2, when applied intrarectally in a rodent model of hapten colitis, hastens mucosal healing and reduces inflammatory indexes. Additionally, TFF2 is expressed in immune organs, supporting a potential immunomodulatory and reparative role in the bowel. In this study we confirm that TFF2 is expressed in the colon and is specifically enriched in epithelial cells relative to colonic leukocytes. TFF2-deficient, but not TFF1-deficient, mice exhibit a more severe response to acute or chronic dextran sulfate (DSS)-induced colitis that correlates with a 50% loss of expression of TFF3, the principal colonic trefoil. In addition, the response to acute colitis is associated with altered expression of IL-6 and IL-33, but not other inflammatory cytokines. While TFF2 can reduce macrophage responsiveness and block inflammatory cell recruitment to the colon, the major role in limiting the susceptibility to acute colitis appears to be maintenance of barrier function. Bone marrow transfer experiments demonstrate that leukocyte expression of TFF2 is not sufficient for prevention of colitis induction but, rather, that the gastrointestinal epithelium is the primary source of TFF2. Together, these findings illustrate that epithelial TFF2 is an important endogenous regulator of gut mucosal homeostasis that can modulate immune and epithelial compartments. Because of its extreme stability, even in the corrosive gut lumen, TFF2 is an attractive candidate as an oral therapeutic scaffold for future drug development in the treatment of inflammatory bowel disease.

Trefoil factor 1 gene alternations and expression in colorectal carcinomas

Aims and background

Aberrant expression of the trefoil factor family (TFF) has been recognized to be involved in the development and/or progression of various solid tumors. Increased trefoil factor 1 (TFF1) expression is found associated with tumor progression in some tumors, and TFF1 missense mutations have been detected in gastric cancer. The aim of the study was to analyze TFF1 alternations and expression in colorectal carcinoma and their correlation with cancer progression and pathological aspects.

Methods

TFF1 mutations were detected in colorectal carcinomas by DNA sequencing. TFF1mRNA and protein levels in subsets of the primary tumors were determined using quantitative reverse transcription polymerase chain reaction and immunohistochemistry analyses. The serum level of TFF1 was also detected by enzyme-linked immunosorbent assay for patients with colorectal carcinoma.

Results

Five variants were detected in the 5'-untranslation region and intron 1 of TFF1. TFF1 expression was increased in colorectal carcinoma compared to paired distal colonic mucosa. Immunohistochemistry in primary colorectal carcinoma showed no significant differences in tumor TFF1 levels with respect to clinicopathological parameters such as the patient's sex, cancer differentiation, stage and lymph node metastasis. However, serum TFF1 levels were significantly elevated in patients with colorectal carcinoma compared to healthy individuals.

Conclusions

The results indicate that TFF1 missense mutations seem to be a rare event in colorectal carcinogenesis. Serum TFF1 may be a potential useful marker for patients with colorectal carcinoma.

Inhibition of ErbB-2 induces TFF3 downregulation in breast cancer cell lines

ErbB-2 gene plays an important role in carcinoma formation whose overexpression was observed in many types of tumors, including breast cancer. Dysregulation of Trefoil factor 3 (TFF3), which is thought to function in the development and progression of breast cancer, was found to be upregulated in ErbB2-overexpressing breast cancers and cells. However, a putative interaction between ErbB-2 and TFF3 in breast cancer remains unknown. To determine whether TFF3 has an important role in breast tumor, its levels were measured by immunohistochemistry in 130 cases of breast infiltrating duct carcinoma and 30 cases of normal breast tissue with a specific monoclonal antibody raised against human TFF3. Patients who were positive for ErbB-2 also had high expression levels of TFF3 (p < 0.05). Also, after infecting the SK-BR-3 cells with lentivirus-mediated ErbB2-specific shRNA (Lenti-ShERBB2), we detected the expressions of ErbB-2 and TFF3 by real-time polymerase chain reaction and Western blotting, respectively. Compared with the control groups, ErbB-2 mRNA expression was decreased in the Lenti-ShERBB2 infection group, and Western blotting indicated a concordant ErbB-2 protein reduction. On the other hand, TFF3 expression at both mRNA and protein levels was significantly downregulated by ErbB-2 silencing in SK-BR-3. These findings are a proof of the foundation for a certain relationships of ErbB-2 and TFF3, which may serve as novel therapeutic markers of ErbB2-overexpressing breast cancers in the future.

Trefoil factor family protein 3 (TFF3) is present in cartilage during endochondral ossification in the developing mouse fetus

Trefoil factor family protein 3 (TFF3) is found in cartilage affected by osteoarthritis and septic arthritis, whereas no TFF3 presence is observed in healthy cartilage. During endochondral ossification, bone tissue replaces degenerating cartilage. There is no data about the role of TFF3 in this process. Our aim was to study the localization of TFF3 in cartilage during endochondral ossification in the mouse fetus. CD1 mouse fetuses, days 14-17, were isolated, fixed, and paraffin embedded. Fetuses were cut into 6μm sections, and processed for immunohistochemical staining with affinity purified polyclonal rabbit anti-TFF3 antibody. TFF3 was present in cartilage chondrocytes undergoing endochondral ossification, particularly in zone of proliferation, hypertrophy and calcification as well as in zone of cartilage degeneration during the monitored fetal period. Resting cartilage showed no presence of TFF3, while during endochondral ossification TFF3 localization showed an analogous pattern to that reported in cartilage affected by osteoarthritis and septic arthritis. Our data indicate that the role of TFF3 in these pathological conditions is similar to its role in the physiological process of endochondral ossification.

Exploiting MEK inhibitor-mediated activation of ERα for therapeutic intervention in ER-positive ovarian carcinoma

While the clinical benefit of MEK inhibitor (MEKi)-based therapy is well established in Raf mutant malignancies, its utility as a suppressor of hyperactive MAPK signaling in the absence of mutated Raf or Ras, is an area of ongoing research. MAPK activation is associated with loss of ERα expression and hormonal resistance in numerous malignancies. Herein, we demonstrate that MEKi induces a feedback response that results in ERα overexpression, phosphorylation and transcriptional activation of ER-regulated genes. Mechanistically, MEKi-mediated ERα overexpression is largely independent of erbB2 and AKT feedback activation, but is ERK-dependent. We subsequently exploit this phenomenon therapeutically by combining the ER-antagonist, fulvestrant with MEKi. This results in synergistic suppression of tumor growth, in vitro and potentiation of single agent activity in vivo in nude mice bearing xenografts. Thus, we demonstrate that exploiting adaptive feedback after MEKi can be used to sensitize ERα-positive tumors to hormonal therapy, and propose that this strategy may have broader clinical utility in ERα-positive ovarian carcinoma.

Trefoil factor 1 suppression of E-CADHERIN enhances prostate carcinoma cell invasiveness and metastasis

Metastasis is the primary mediator of prostate cancer (PCA) lethality and poses a significant clinical obstacle. The identification of factors involved in the metastasis of PCA is imperative. We demonstrate herein that trefoil factor 1 (TFF1) promotes PCA cell migration and invasion in vitro and metastasis in vivo. The capacity of TFF1 to enhance cell migration/invasion is mediated by transcriptional repression of E-CADHERIN. Consideration of targeted inhibition of TFF1 to prevent metastasis of prostate carcinoma is warranted.

Increased trefoil factor 3 levels in the serum of patients with three major histological subtypes of lung cancer

Lung cancer is the most common cause of cancer-related deaths in the world. The trefoil factor (TFF) family is composed of three thermostable, and protease-resistant proteins, named TFF1, TFF2 and TFF3. TFF protein levels have been found to be related to the development of various types of cancer. However, it is still unclear whether TFF proteins are differentially expressed in the serum of different histological subtypes of lung cancer compared to healthy individuals. In this study, we investigated the levels of TFF proteins in serum and lung tissues of 130 lung cancer patients (58 squamous cell lung carcinoma cases, 43 adenocarcinoma cases and 29 SCLC cases) and 60 healthy individuals. It was found that TFF1 and TFF2 have similar or slightly higher levels in these three subtypes of lung cancer compared to healthy individuals, while TFF3 levels were significantly higher in the examined lung cancer cases compared to healthy individuals. Immunoblot analyses of TFF1, TFF2 and TFF3 indicated that lung cancer tissues and lung cancer cell lines have a higher expression of the TFF3 protein, but not of TFF1 or TFF2 proteins, compared to tissues from healthy individuals or from the normal cell line. Quantitative RT-PCR analysis indicated higher levels of TFF3, but not TFF1 and TFF2, transcripts in lung cancer tissues or cell lines. These results show increased TFF3 levels in serum and lung tissues, suggesting that TFF3 may serve as a promising, easily detected biomarker of lung cancer.

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

OBJECTIVES

The aims of our study were to determine levels of trefoil factor (TFF) peptides in saliva and oral mucosal tissues from patients with oral squamous cell carcinoma (OSCC), and to evaluate whether individual members of TFFs (TFF1, TFF2, and TFF3) might act as biomarkers of disease.

MATERIALS AND METHODS

Saliva samples were from 23 healthy subjects and 23 OSCC patients. Tissue samples were collected from 32 normal oral mucosa (NOM) and 32 OSCC biopsy specimens. ELISA and immunohistochemical methods were used to evaluate the expression of TFF1, TFF2, and TFF3 in saliva and oral mucosal tissues, respectively.

RESULTS

Expression of TFF2 and TFF3 in oral mucosal tissues of OSCC patients was strongly downregulated when compared to healthy subjects (p < 0.001 and p = 0.002, respectively). However, there were no differences in levels of salivary TFF concentrations between OSCC patients and healthy subjects.

CONCLUSIONS

The present study extends previous observations, demonstrating the reduction of TFF2 and TFF3 expression in oral mucosal tissues of OSCC patients.

CLINICAL RELEVANCE

These findings suggest the clinical significance of TFF2 and TFF3 molecules as negative markers of tumor progression in OSCC. Quantification of TFF levels in saliva may not be optimal in terms of diagnostic or predictive value for OSCC derived from oral mucosa.

Trefoil factor family peptides are increased in the saliva of children with mucositis

BACKGROUND

Mucositis is a painful ulcerative condition of the oral cavity and gastrointestinal tract, occurring in association with chemotherapy and radiotherapy regimes. Trefoil factor family peptides (TFF, trefoil peptides), present in saliva, contribute to epithelial restitution and repair and are therefore potentially important in the healing phase of mucositis. This study aimed to assess any changes in the levels of trefoil peptides in oncology patients with and without mucositis.

METHODS

Saliva was collected from healthy children, pretreatment oncology patients, neutropenic patients on treatment with no oral disease and mucositic patients. TFF1, 2 and 3 were quantified using ELISA.

RESULTS

In healthy children TFF2 and 3 were positively correlated with age (r = 0.454, p = 0.01 for TFF2; r = 0.410, p = 0.05 for TFF3 Spearman rank correlation). TFF3 was higher in mucositis compared to all other groups. A linear regression prediction model indicated that TFF3, but not TFF1 and TFF2, was significantly different in mucositic and healthy controls, suggesting an altered pattern of trefoil peptide secretion (p = 0.021).

CONCLUSIONS

This study is the first to focus on trefoil peptides in paediatric saliva. It shows the correlation between TFF2, TFF3 and age in healthy children. Paediatric mucositis disease occurs in the presence of increased concentrations and an altered pattern of trefoil peptides.

Characterization of the βγ-crystallin domains of βγ-CAT, a non-lens βγ-crystallin and trefoil factor complex, from the skin of the toad Bombina maxima

βγ-CAT is a naturally existing 72-kDa complex of a non-lens βγ-crystallin (α-subunit, CAT-α) and a trefoil factor (β-subunit, CAT-β) that contains a non-covalently linked form of αβ(2) and was isolated from the skin secretions of the toad Bombina maxima. The N-terminal region of CAT-α (CAT-αN, residues 1-170) contains two βγ-crystallin domains while the C-terminal region (CAT-αC) has sequence homology to the membrane insertion domain of the Clostridium perfringens epsilon toxin. To examine the biochemical characteristics of the βγ-crystallin domains of βγ-CAT, CAT-αN, CAT-αC and CAT-β were expressed in Escherichia coli. Co-immunoprecipitation of the naturally assembled βγ-CAT confirmed that the CAT-α and CAT-β complex always exists. Furthermore, recombinant CAT-β bound recombinant CAT-αN. Ca(2+)-binding motifs were identified in CAT-αN, and recombinant CAT-αN was able to bind the calcium probe terbium. However, the conformation of CAT-αN was not significantly altered upon Ca(2+) binding. βγ-CAT possesses strong hemolytic activity toward human erythrocytes, and treatment of erythrocytes with βγ-CAT resulted in a rapid Ca(2+) influx, eventually leading to hemolysis. However, in the absence of extracellular Ca(2+), no significant hemolysis was detected, even though the binding and oligomerization of βγ-CAT in the erythrocyte membrane was observed. Our data demonstrate the binding of CAT-β (a trefoil factor) to CAT-αN (βγ-crystallin domains) and provide a basis for the formation of a βγ-crystallin and trefoil factor complex in vivo. Furthermore, the βγ-crystallin domains of βγ-CAT are able to bind Ca(2+), and βγ-CAT-induced hemolysis is Ca(2+) dependent.

Decrease of Trefoil factor 2 in cats with feline idiopathic cystitis

OBJECTIVE

To obtain new insights into aetiological backgrounds, and to search for diagnostic biomarkers by assessing the difference in urinary proteins between cats with spontaneous feline idiopathic cystitis (FIC) and healthy controls.

MATERIALS AND METHODS

Urine supernatants of 18 cats with FIC and 18 healthy control cats, and bladder biopsies of two FIC diseased cats and four healthy controls were included in the study. The Bradford method was used to determine protein quantity in urine supernatants. Urine was separated by two-dimensional (2-D) gel electrophoresis. Selected protein spots were excised from two-dimensional gels and analysed with tandem mass spectrometry. Validation of Trefoil factor 2 expression was realized with Western blot and immunohistochemistry. Western blot signal intensities were quantified with image quant software.

RESULTS

Eleven differentially expressed protein spots were identified between the 2-D gels of cats with FIC and control cats. Ten spots (only visible in the FIC gel) were identified as albumin and one spot (only visible in the control gel) was identified as Trefoil factor 2.Using quantification of Western blot signal intensities and immunohistochemistry a decrease in Trefoil factor 2 (TFF2) in cats with FIC could be revealed for the first time.

CONCLUSION

Deficiency in TFF2 possibly leads to impaired repairing abilities and immune response of the urothelium. The result could be a greater susceptibility to injury, inflammation and relapse. Therefore TFF2 deficiency might be an important event in FIC pathogenesis. Detection of a decrease in urinary TFF2 could serve as diagnostic biomarker, facilitating diagnosis. As FIC can serve as an animal model for human painful bladder syndrome/interstitial cystitis, the findings of this study might also be valuable for interstitial cystitis research and should be further investigated.

Trefoil factor 3 is oncogenic and mediates anti-estrogen resistance in human mammary carcinoma

We report herein that trefoil factor 3 (TFF3) is oncogenic and mediates anti-estrogen resistance in human mammary carcinoma. Forced expression of TFF3 in mammary carcinoma cells increased cell proliferation and survival, enhanced anchorage-independent growth, and promoted migration and invasion. Moreover, forced expression of TFF3 increased tumor size in xenograft models. Conversely, depletion of endogenous TFF3 with small interfering RNA (siRNA) decreased the oncogenicity and invasiveness of mammary carcinoma cells. Neutralization of secreted TFF3 by antibody promoted apoptosis, decreased cell growth in vitro, and arrested mammary carcinoma xenograft growth. TFF3 expression was significantly correlated to decreased survival of estrogen receptor (ER)-positive breast cancer patients treated with tamoxifen. Forced expression of TFF3 in mammary carcinoma cells increased ER transcriptional activity, promoted estrogen-independent growth, and produced resistance to tamoxifen and fulvestrant in vitro and to tamoxifen in xenograft models. siRNA-mediated depletion or antibody inhibition of TFF3 significantly enhanced the efficacy of antiestrogens. Increased TFF3 expression was observed in tamoxifen-resistant (TAMR) cells and antibody inhibition of TFF3 in TAMR cells improved tamoxifen sensitivity. Functional antagonism of TFF3 therefore warrants consideration as a novel therapeutic strategy for mammary carcinoma.

Deficiency in trefoil factor 1 (TFF1) increases tumorigenicity of human breast cancer cells and mammary tumor development in TFF1-knockout mice

Although trefoil factor 1 (TFF1; previously named pS2) is abnormally expressed in about 50% of human breast tumors, its physiopathological role in this disease has been poorly studied. Moreover, controversial data have been reported. TFF1 function in the mammary gland therefore needs to be clarified. In this study, using retroviral vectors, we performed TFF1 gain- or loss-of-function experiments in four human mammary epithelial cell lines: normal immortalized TFF1-negative MCF10A, malignant TFF1-negative MDA-MB-231 and malignant TFF1-positive MCF7 and ZR75.1. The expression of TFF1 stimulated the migration and invasion in the four cell lines. Forced TFF1 expression in MCF10A, MDA-MB-231 and MCF7 cells did not modify anchorage-dependent or -independent cell proliferation. By contrast, TFF1 knockdown in MCF7 enhanced soft-agar colony formation. This increased oncogenic potential of MCF7 cells in the absence of TFF1 was confirmed in vivo in nude mice. Moreover, chemically induced tumorigenesis in TFF1-deficient (TFF1-KO) mice led to higher tumor incidence in the mammary gland and larger tumor size compared with wild-type mice. Similarly, tumor development was increased in the TFF1-KO ovary and lung. Collectively, our results clearly show that TFF1 does not exhibit oncogenic properties, but rather reduces tumor development. This beneficial function of TFF1 is in agreement with many clinical studies reporting a better outcome for patients with TFF1-positive breast primary tumors.

Trefoil factor: implications for clinical laboratory diagnostics

Trefoil factors (TFF), expressed physiologically in the secretory cells of gastrointestinal mucosa and other mucosal tissues, compose a unique peptide family with important biologic functions. Aberrant expression and/or continued secretion of TFF might exist concurrently with the processes of digestive system inflammation, tumor or other related pathological changes. Previous pathological studies have shown that the abnormal expression of TFF is associated with the prognosis of digestive system diseases. The results obtained from gene expression profiling, tumor secretomics and bioinformatic analysis have positively confirmed that clinical detection of TFF peptides or mRNAs has an excellent diagnostic performance to detect digestive system diseases, especially for the monitoring of recurrence or metastasis of tumors and for the estimation of therapeutic efficacy and prognosis. Therefore, TFF is a potential biomarker for diagnosis, treatment and prognosis of digestive system diseases.

[Trefoil factor: from laboratory to clinic]

Trefoil factor (TFF) family is a group of peptides with one or several trefoil factor domains in their structure, which are highly conserved in evolution, and are characterized by heat and enzymatic digestion resistance. The mammalian TFFs have three members (TFF1-3), and the gastrointestinal tract and the airway system are major organs of their expression and secretion. At certain physiological conditions, with a tissue-specific distribution, TFF plays an important role in mucosal protection and wound healing. But in the malignant tissues, TFF is widely expressed, correlated strongly with the genesis, metastasis and invasion of tumor cells. These phenomena indicated that TFF may be a possible common mediator of oncogenic responses to different stimuli. The biological functions of TFF involve complex regulatory processes. Single chain TFF may activate cell membrane receptors and induce specific signaling transduction. On the other hand, TFF can form a complex with other proteins to exert its biological effects. In clinical medicine, TFF is primarily applied as drugs in the mucosal protection, in the prevention and the treatment of mucosal damage-related diseases and as pathological biomarkers of tumors. At present the first hand actions and the molecular mechanisms related to TFFs are still the major challenges in TFF research. Furthermore, the discovery of the naturally occurring complex of TFF and crystallins is highly valuable to the understanding of the biological functions and action mechanisms of TFF.

Trefoil factor-1 (TFF1) enhances oncogenicity of mammary carcinoma cells

The functional role of autocrine trefoil factor-1 (TFF1) in mammary carcinoma has not been previously elucidated. Herein, we demonstrate that forced expression of TFF1 in mammary carcinoma cells resulted in increased total cell number as a consequence of increased cell proliferation and survival. Forced expression of TFF1 enhanced anchorage-independent growth and promoted scattered cell morphology with increased cell migration and invasion. Moreover, forced expression of TFF1 increased tumor size in xenograft models. Conversely, RNA interference-mediated depletion of TFF1 in mammary carcinoma cells significantly reduced anchorage-independent growth and migration. Furthermore, neutralization of secreted TFF1 protein by polyclonal antibody decreased mammary carcinoma cell viability in vitro and resulted in regression of mammary carcinoma xenografts. We have therefore demonstrated that TFF1 possesses oncogenic functions in mammary carcinoma cells. Functional antagonism of TFF1 can therefore be considered as a novel therapeutic strategy for mammary carcinoma.

Advance in relationship between TFF3 and gastric cancer

Trefoil factor family (TFF) consists of three members, including TFF1, TFF2 and TFF3. TFF has such functions as maintaining gut mucosal integrity, promoting epithelial cell restitution, as well as cell signal transduction, modulating apoptosis and enhancing invasion. Therefore, TFF plays crucial roles in the process of inflammation and tumorigenesis. Researches recently have indicated that TFF3 plays an important role in gastric cancer, especially in intestinal gastric carcinoma.

How form follows functional genomics: gene expression profiling gastric epithelial cells with a particular discourse on the parietal cell

The cellular composition and morphology of the stomach epithelium have been described in detail; however, the molecular mechanisms that regulate the differentiation of the various cell lineages as well as the function of mature gastric cells are far less clear. Recently, dissection of the molecular anatomy of the stomach has been boosted by the advent of functional genomics, which allows investigators to determine patterns of gene expression across virtually the entire cellular transcriptome. In this review, we discuss the impact of functional genomic studies on the understanding of gastric epithelial physiology. We show how functional genomic studies have uncovered genes that are useful as new cell lineage-specific markers of differentiation and provide new insights into cell physiology. For example, vascular endothelial growth factor B (Vegfb) has been identified as a parietal cell-specific marker that may allow parietal cells to regulate the mucosal vascular network. We also discuss how functional genomics has identified aberrantly expressed genes in disease states. Human epididymis 4 (HE4), for example, was recently identified as a metaplasia-induced gene product in mice based on microarray analysis. Finally, we will examine how analysis of higher-order patterns of gene expression can go beyond simply identifying individual genes to show how cells work as integrated systems. Specifically, we show how application of a Gene Ontology (GO) analysis of gene expression patterns from multiple tissues identifies the gastric parietal cell as an outlier, unlike other differentiated cell lineages in the stomach or elsewhere in the body.

Decreased expression of gastrokine 1 and the trefoil factor interacting protein TFIZ1/GKN2 in gastric cancer: influence of tumor histology and relationship to prognosis

PURPOSE

Transcriptional profiling showed decreased expression of gastrokine 1 (GKN1) and the related trefoil factor interacting protein (TFIZ1/GKN2) in Helicobacter pylori infection. Decreased GKN1 and GKN2 mRNA expression has been reported in gastric adenocarcinoma. We have examined GKN1 and GKN2 protein expression in a large gastric cancer series, correlated expression with tumor subtype, and evaluated their utility as prognostic biomarkers.

EXPERIMENTAL DESIGN

GKN1, GKN2, and the trefoil factors TFF1 and TFF3 were examined in tissue microarrays from 155 distal gastric adenocarcinomas. Immunohistochemical expression was correlated with clinical outcome. GKN1 and GKN2 expression was measured by real-time PCR and Western analysis in samples of gastric cancer and adjacent nonneoplastic mucosa.

RESULTS

GKN1 was lost in 78% of diffuse and 42% of intestinal cancers (P < 0.0001, diffuse versus intestinal). GKN2 expression was lost in 85% of diffuse and 54% of intestinal type cancers (P < 0.002). GKN1 and GKN2 down-regulation were confirmed by Western and real-time PCR analysis. Loss of either protein was associated with significantly worse outcome in intestinal-type tumors by univariate analysis; and GKN2 loss remained a predictor of poor outcome in multivariate analysis (P < 0.033). TFF1 was lost in >70%, and TFF3 was expressed in approximately 50% of gastric cancers.

CONCLUSIONS

Loss of GKN1 and GKN2 expression occurs frequently in gastric adenocarcinomas, especially in the diffuse subtype. GKN1 and GKN2 loss are associated with shorter overall survival in the intestinal subtype.

The contribution of growth hormone to mammary neoplasia

While the effects of growth hormone (GH) on longitudinal growth are well established, the observation that GH contributes to neoplastic progression is more recent. Accumulating literature implicates GH-mediated signal transduction in the development and progression of a wide range malignancies including breast cancer. Recently autocrine human GH been demonstrated to be an orthotopically expressed oncogene for the human mammary gland. This review will highlight recent evidence linking GH and mammary carcinoma and discuss GH-antagonism as a potential therapeutic approach for treatment of breast cancer.

Are trefoil factors oncogenic?

Trefoil factors (TFFs), in particular TFF1, are classical estrogen-regulated genes and have served as markers of estrogen gene regulation by various environmental estrogens. TFFs are also regulated by several other factors including growth hormone (hGH), insulin-like growth factor-1 (IGF-1), epidermal growth factor (EGF) and various oncogenic stimuli. TFFs are secreted proteins present in serum and possess the potential to act as growth factors promoting cell survival, anchorage-independent growth and motility. Recent compelling evidence has emerged from experimental and clinical studies to indicate a pivotal role of TFFs in oncogenic transformation, growth and metastatic extension of common human solid tumours. This review will summarize the current evidence for the involvement of TFFs in human cancer.

Reduced Shh expression in TFF2-overexpressing lesions of the gastric fundus under hypochlorhydric conditions

Expression of sonic hedgehog (Shh), a morphogen for the gastric fundic glands, is reduced in the atrophic mucosa that develops in association with Helicobacter pylori infection, resulting in impaired differentiation of the fundic gland cells, increased expression of trefoil factor family 2 (TFF2) and the formation of spasmolytic polypeptide (SP)-expressing metaplasia (SPEM), a preneoplastic lesion. However, it is still unresolved whether H. pylori-induced inflammation and the resultant reduction in parietal cell number or reduced parietal cell function per se reduces Shh expression. The present study was designed to clarify the expression of Shh and TFF2 in the context of parietal cell dysfunction in the absence of inflammation, using histamine H(2) receptor-knockout (H(2)R-null) mice and an acid exposure model. Age-matched H(2)R-null mice and wild-type (WT) mice were used. The expression of Shh and TFF2 mRNA was quantified by quantitative RT-PCR. Immunohistochemistry was also performed to detect the expression of Shh, TFF2 and cell markers. To study the effects of acid exposure, HCl solution was administered to the animals. The H(2)R-null mice exhibited higher gastric pH, increased TFF2 expression and reduced Shh expression. Impaired mucous neck-to-zymogenic cell differentiation was observed in the H(2)R-null mice. Furthermore, Shh expression increased in the presence of gastric acid and showed a significant correlation with gastric surface pH. In conclusion, our results suggest that persistent parietal cell dysfunction alone (suppressed gastric acid secretion), in the absence of inflammation or parietal cell loss caused by H. pylori infection, may be sufficient to down-regulate Shh expression in TFF2-overexpressing preneoplastic lesions of the gastric fundus. Since exposure to acid restored fundic Shh expression, appropriate gastric acid secretion may play an important role in the morphogen dynamics involved in the maintenance of gastric fundic gland homeostasis.

TFF3 and EGF induce different migration patterns of intestinal epithelial cells in vitro and trigger increased internalization of E-cadherin

BACKGROUND/AIMS

TFF3, a member of the TFF (trefoil factor family) peptides, and epidermal growth factor (EGF) actively support the repair of mucosal barriers, particularly during restitution. The aim of this study was to compare the motogenic effects of TFF3 and EGF.

METHODS

The influence of recombinant human TFF3 (dimeric form) and EGF on the migration of IEC-18 cells was characterized in an in vitro restitution model (scratch wound assay) with the help of time-lapse video microscopy, morphometry, and immunocytochemistry including confocal laser scanning microscopy.

RESULTS

TFF3- and EGF-treated cells re-populated the wounded area via different migration patterns; TFF3 treatment resulted in the formation of continuous sheets of migrating cells with only a few gaps. In contrast, EGF-treated cells formed a network of migrating cells (often with a fibroblast-like morphology) with numerous gaps and only punctual contacts. TFF3 and EGF treatment also changed the localization of E-cadherin indicating endocytotic recycling and/or degradation of E-cadherin.

CONCLUSION

TFF3, in contrast to EGF, enhanced a collective cell migration ensuring a precise coverage of the re-populated area avoiding gaps.

Differentiation of the Gastric Mucosa IV. Role of trefoil peptides and IL-6 cytokine family signaling in gastric homeostasis

Gastric trefoil peptides mediate mucosal repair by stimulating cell migration, inhibiting apoptosis and inflammation, and likely augmenting the barrier function of mucus. One of these, tff1, is a gastric-specific tumor suppressor gene, which when repressed is associated with gastric cancer progression. IL-6 family cytokines play an important role in maintaining gastric homeostasis by regulating tff1 and other mediators of mucosal proliferation, inflammation, angiogenesis, and apoptosis. In this review the signaling cascades downstream of the common IL-6 cytokine family coreceptor gp130 that contribute to control of this homeostasis are described, as are the pathological outcomes of imbalancing these pathways.