Trefoil factor family-3 is associated with aggressive behavior of colon cancer cells

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.

CD147 receptor is essential for TFF3-mediated signaling regulating colorectal cancer progression

Major gaps in understanding the molecular mechanisms of colorectal cancer (CRC) progression and intestinal mucosal repair have hampered therapeutic development for gastrointestinal disorders. Trefoil factor 3 (TFF3) has been reported to be involved in CRC progression and intestinal mucosal repair; however, how TFF3 drives tumors to become more aggressive or metastatic and how TFF3 promotes intestinal mucosal repair are still poorly understood. Here, we found that the upregulated TFF3 in CRC predicted a worse overall survival rate. TFF3 deficiency impaired mucosal restitution and adenocarcinogenesis. CD147, a membrane protein, was identified as a binding partner for TFF3. Via binding to CD147, TFF3 enhanced CD147-CD44s interaction, resulting in signal transducer and activator of transcription 3 (STAT3) activation and prostaglandin G/H synthase 2 (PTGS2) expression, which were indispensable for TFF3-induced migration, proliferation, and invasion. PTGS2-derived PGE2 bound to prostaglandin E2 receptor EP4 subtype (PTGER4) and contributed to TFF3-stimulated CRC progression. Solution NMR studies of the TFF3-CD147 interaction revealed the key residues critical for TFF3 binding and the induction of PTGS2 expression. The ability of TFF3 to enhance mucosal restitution was weakened by a PTGS2 inhibitor. Blockade of TFF3-CD147 signaling using competitive inhibitory antibodies or a PTGS2 inhibitor reduced CRC lung metastasis in mice. Our findings bring strong evidence that CD147 is a novel receptor for TFF3 and PTGS2 signaling is critical for TFF3-induced mucosal restitution and CRC progression, which widens and deepens the understanding of the molecular function of trefoil factors.

Odyssey of trefoil factors in cancer: Diagnostic and therapeutic implications

Trefoil factors 1, 2, and 3 (TFFs) are a family of small secretory molecules involved in the protection and repair of the gastrointestinal tract (GI). TFFs maintain and restore epithelial structural integrity via transducing key signaling pathways for epithelial cell migration, proliferation, and invasion. In recent years, TFFs have emerged as key players in the pathogenesis of multiple diseases, especially cancer. Initially recognized as tumor suppressors, emerging evidence demonstrates their key role in tumor progression and metastasis, extending their actions beyond protection. However, to date, a comprehensive understanding of TFFs' mechanism of action in tumor initiation, progression and metastasis remains obscure. The present review discusses the structural, functional and mechanistic implications of all three TFF family members in tumor progression and metastasis. Also, we have garnered information from studies on their structure and expression status in different organs, along with lessons from their specific knockout in mouse models. In addition, we highlight the emerging potential of using TFFs as a biomarker to stratify tumors for better therapeutic intervention.

Pharmacological Inhibition of TFF3 Enhances Sensitivity of CMS4 Colorectal Carcinoma to 5-Fluorouracil through Inhibition of p44/42 MAPK

Increased expression of trefoil factor 3 (TFF3) has been reported in colorectal carcinoma (CRC), being correlated with distant metastasis and poor clinical outcomes. Amongst the CRC subtypes, mesenchymal (CMS4) CRC is associated with the worst survival outcome. Herein, the functional roles of TFF3 and the pharmacological inhibition of TFF3 by a novel specific small molecule TFF3 inhibitor—2-amino-4-(4-(6-fluoro-5-methylpyridin-3-yl)phenyl)-5-oxo-4H,5H-pyrano[3,2-c]chromene-3-carbonitrile (AMPC) in CMS4 CRC was explored. Forced expression of TFF3 in CMS4 CRC cells promoted cell proliferation, cell survival, foci formation, invasion, migration, cancer stem cell like behaviour and growth in 3D Matrigel. In contrast, siRNA-mediated depletion of TFF3 or AMPC inhibition of TFF3 in CMS4 CRC cells decreased oncogenic behaviour as indicated by the above cell function assays. AMPC also inhibited tumour growth in vivo. The TFF3-stimulated oncogenic behaviour of CMS4 CRC cells was dependent on TFF3 activation of the p44/42 MAPK (ERK1/2) pathway. Furthermore, the forced expression of TFF3 decreased the sensitivity of CMS4 CRC cells to 5-fluorouracil (5-FU); while depleted TFF3 expression enhanced 5-FU sensitivity in CMS4 CRC cells. 5-FU treatment induced TFF3 expression in CMS4 CRC cells. AMPC, when used in combination with 5-FU in CMS4 CRC cells exhibited a synergistic inhibitory effect. In summary, this study provides functional evidence for TFF3 as a therapeutic target in CMS4 CRC.

Trefoil factor 3 mediation of oncogenicity and chemoresistance in hepatocellular carcinoma is AKT-BCL-2 dependent

The efficacious treatment of hepatocellular carcinoma (HCC) remains a challenge, partially being attributed to intrinsic chemoresistance. Previous reports have observed increased TFF3 expression in HCC. Herein, we investigated the functional role of TFF3 in progression of HCC, and in both intrinsic and acquired chemoresistance. TFF3 expression was observed to be upregulated in HCC and associated with poor clinicopathological features and worse patient survival outcome. Functionally, forced expression of TFF3 in HCC cell lines increased cell proliferation, cell survival, anchorage-independent and 3D matrigel growth, cell invasion and migration, and in vivo tumor growth. In contrast, depleted expression of TFF3 decreased the oncogenicity of HCC cells as indicated by the above parameters. Furthermore, forced expression of TFF3 decreased doxorubicin sensitivity of HCC cells, which was attributed to increased doxorubicin efflux and cancer stem cell-like behavior of Hep3B cells. In contrast, depletion of TFF3 increased doxorubicin sensitivity and decreased cancer stem cell-like behavior of Hep3B cells. Correspondingly, TFF3 expression was markedly increased in Hep3B cells with acquired doxorubicin resistance, while the depletion of TFF3 resulted in re-sensitization of the Hep3B cells to doxorubicin. The increased doxorubicin efflux and enhanced cancer stem cell-like behavior of the doxorubicin-resistant Hep3B cells was observed to be dependent on TFF3 expression. In addition, we determined that TFF3-stimulated oncogenicity and chemoresistance in HCC cells was mediated by AKT-dependent expression of BCL-2. Hence, therapeutic inhibition of TFF3 should be considered to hinder HCC progression and overcome intrinsic and acquired chemoresistance in HCC.

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.

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.

Forced Trefoil Factor Family Peptide 3 (TFF3) Expression Reduces Growth, Viability, and Tumorigenicity of Human Retinoblastoma Cell Lines

Trefoil factor family (TFF) peptides have been shown to effect cell proliferation, apoptosis, migration and invasion of normal cells and various cancer cell lines. In the literature TFF peptides are controversially discussed as tumor suppressors and potential tumor progression factors. In the study presented, we investigated the effect of TFF3 overexpression on growth, viability, migration and tumorigenicity of the human retinoblastoma cell lines Y-79, WERI-Rb1, RBL-13 and RBL-15. As revealed by WST-1 and TUNEL assays as well as DAPI and BrdU cell counts, recombinant human TFF3 significantly lowers retinoblastoma cell viability and increases apoptosis levels. Transient TFF3 overexpression likewise significantly increases RB cell apoptosis. Stable, lentiviral TFF3 overexpression lowers retinoblastoma cell viability, proliferation and growth and significantly increases cell death in retinoblastoma cells. Blockage experiments using a broad-spectrum caspase inhibitor and capase-3 immunocytochemistry revealed the involvement of caspases in general and of caspase-3 in particular in TFF3 induced apoptosis in retinoblastoma cell lines. Soft agarose and in ovo chicken chorioallantoic membrane (CAM) assays revealed that TFF3 overexpression influences anchorage independent growth and significantly decreases the size of tumors forming from retinoblastoma cells. Our study demonstrates that forced TFF3 expression exerts a significant pro-apoptotic, anti-proliferative, and tumor suppressive effect in retinoblastoma cells, setting a starting point for new additive chemotherapeutic approaches in the treatment of retinoblastoma.

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.

The value of trefoil factor 3 expression in predicting the long‑term outcome and early recurrence of colorectal cancer

The trefoil factor (TFF) family comprises three thermo-stable and protease-resistant proteins (TFF1, TFF2 and TFF3) and plays an essential role in gastrointestinal mucosa protection and regeneration, and TFFs have recently been found to be involved in the development and progression of various types of cancer. However, the clinical significance of TFFs in colorectal cancer (CRC) patients remains unclear. The present study determined the relationship between TFF expression and clinicopathological findings, as well as long-term outcome in CRC patients. The mRNA expression levels of TFFs were examined in the excised CRC specimens obtained from 154 consecutive CRC patients who underwent surgical resection between 2005 and 2007 at our institution. TFF3 expression was significantly associated with the presence of distant metastasis (p=0.017), although neither TFF1 nor TFF2 expression was associated with the clinicopathological features. Survival rate of the patients with positive TFF3 was significantly worse compared to those with negative TFF3 (p=0.011). A multivariate analysis revealed that the expression of TFF3, lymph node metastasis, and vascular invasion were independent prognostic factors for disease-specific survival. Furthermore, among 134 patients with no clinical findings of metastasis at surgery, the patients with positive TFF3 experienced recurrence within one year more frequently than those with negative TFF3 (p=0.039). In conclusion, TFF3 is not only a useful biomarker for a long-term surgical result in CRC patient, but also may be a risk factor of early recurrence.

Serum trefoil factor 3 is a promising non-invasive biomarker for gastric cancer screening: a monocentric cohort study in China

BACKGROUND

The search for better non-invasive biomarkers for gastric cancer remains ongoing. We investigated the predictive power of serum trefoil factor (TFF) levels as biomarkers for gastric cancer in comparison with the pepsinogen (PG) test.

METHODS

Patients with gastric cancer, chronic atrophic gastritis (CAG) or chronic non-atrophic gastritis (CNAG), and healthy people were recruited. Serum concentrations of TFFs, PG I, and PG II, as well as the presence of antibodies against Helicobacter pylori, were measured by enzyme-linked immunosorbent assays (ELISA). Receiver operating characteristics (ROC) were used to compare the predictive powers of the selected factors.

RESULTS

The serum concentrations of TFF1, TFF2, and TFF3 in the control groups were significantly lower than those in the gastric cancer group with the exception of TFF2 which was elevated in CAG. The area under the ROC curve for TFF3 was greater than that for the PG I/II ratio (0.81 vs 0.78). TFF3 also had a significantly higher predictive power for distinguishing gastric cancer than the PG test (odds ratio: 10.33 vs 2.57). Moreover, combining the serum TFF3 and PG tests for gastric cancer had better predictive power than either alone.

CONCLUSIONS

Serum TFF3 may be a better predictor of gastric cancer than the PG test, while the combined testing of serum PG and TFF3 could further improve the efficacy of gastric cancer screening.

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.

Reduced expression of TFF1 and increased expression of TFF3 in gastric cancer: correlation with clinicopathological parameters and prognosis

OBJECTIVES

The trefoil factor family (TFF) is composed of three thermostable, and protease-resistant proteins, named TFF1, TFF2 and TFF3, and plays a role in gastrointestinal mucosal defence and repair. Recently, TFFs have been found to be related to the development of various types of cancer. This study assessed the relationship between the expression of TFF1 and TFF3 and the clinicopathological parameters in gastric carcinoma (GC).

MATERIALS AND METHODS

The expression of TFF1 and TFF3 was analyzed by immunohistochemistry in 292 GCs and 20 normal gastric tissues.

RESULTS

All normal gastric tissues expressed TFF1, but 53.8% of GCs showed reduced TFF1 expression. However, TFF3 was not detected in normal gastric tissues and 44.2% of GCs showed a high level of expression. Highly expressed TFF3 was significantly correlated with lymph node metastasis, lymphatic invasion, vein invasion, and advanced stage. The overall survival was shorter in patients with high expression of TFF3 than in those with low expression of TFF3 in 292 GCs and in 125 early GCs (EGCs). Moreover, in patients with EGCs, high expression of TFF3, associated with reduced expression of TFF1, was determined as an independent poor prognostic marker.

CONCLUSIONS

Reduced expression of TFF1 and increased expression of TFF3 may play a role in the carcinogenesis of gastric cancer. Furthermore, high expression of TFF3 with reduced expression of TFF1 may be a marker of poor prognosis for patients with EGC.

Trefoil factor family peptides in normal and diseased human pancreas

OBJECTIVES

Trefoil factor family (TFF) peptides promote wound healing in the gut. Recent evidence has suggested that TFF3 may be a pancreatic mitogen, an unusual role for TFF peptides. We sought to clarify human pancreatic TFF and mucin expression and performed in vitro experiments to see how pancreatic cell lines respond to TFF3 in particular.

METHODS

Samples of normal and diseased pancreas (chronic pancreatitis, pancreatic intraepithelial neoplasia, neuroendocrine tumors, and pancreatic ductal adenocarcinoma [PDAC]) were studied by immunohistochemistry and in situ hybridization. Pancreatic cell lines were challenged with TFF2 and TFF3 in wound and migration assays.

RESULTS

In normal islets, colocalization of insulin or glucagon with TFF3 was common. All TFF messenger RNAs were seen in ductal epithelium. Adenocarcinomas expressed all TFF messenger RNAs. Normal ducts were mucin free; MUC5AC was strongest in pancreatic intraepithelial neoplasia and chronic pancreatitis but was reduced in PDAC. TFF2 induced Panc-1 migration and accelerated wound closure in Capan-2 and COLO-357. Double immunohistochemistry for insulin or TFF3 and Ki67 colabeled only very rare islet cells. TFF3-positive PDAC ducts showed some Ki67 colocalization.

CONCLUSIONS

No correlation between TFF3 or insulin and Ki67 was seen without ductal hyperplasia. TFF2 may assist pancreatic tumor cell movement, but TFF3 may not be a pancreatic mitogen.

TFF3 is a normal breast epithelial protein and is associated with differentiated phenotype in early breast cancer but predisposes to invasion and metastasis in advanced disease

The trefoil protein TFF3 stimulates invasion and angiogenesis in vitro. To determine whether it has a role in breast tumor metastasis and angiogenesis, its levels were measured by immunohistochemistry in breast tissue with a specific monoclonal antibody raised against human TFF3. TFF3 is expressed in normal breast lobules and ducts, at higher levels in areas of fibrocystic change and papillomas, in all benign breast disease lesions, and in 89% of in situ and in 83% of invasive carcinomas. In well-differentiated tumor cells, TFF3 is concentrated at the luminal edge, whereas in poorly differentiated cells polarity is inverted and expression is directed toward the stroma. Expression was high in well-differentiated tumors and was associated significantly with low histological grade and with estrogen and progesterone receptor expression, accordant with induction of TFF3 mRNA by estrogen in breast cancer cells. Paradoxically, TFF3 expression was associated with muscle, neural, and lymphovascular invasion and the presence and number of involved lymph nodes, and it was an independent predictive marker of lymphovascular invasion and lymph node involvement. Consistent with an angiogenic function, TFF3 expression correlated strongly with microvessel density evaluated with CD31 and CD34. In conclusion, TFF3 is expressed in both the normal and diseased breast. Although associated with features of good prognosis, its profile of expression in invasive cancer is consistent with a role in breast tumor progression and tumor cell dissemination.

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.

Validity of multiplex biomarker model of 6 genes for the differential diagnosis of thyroid nodules

Background

Currently the cytological examination of fine needle aspiration (FNA) biopsies is the standard technique for the pre-operative differential diagnosis of thyroid nodules. However, the results may be non-informative in ~20% of cases due to an inadequate sampling and the lack of highly specific, measurable cytological criteria, therefore ancillary biomarkers that could aid in these cases are clearly needed. The aim of our study was to evaluate the mRNA expression levels of 8 candidate marker genes as the diagnostic biomarkers for the discrimination of benign and malignant thyroid nodules and to find a combination of biomarkers with the highest diagnostic value.

Materials and methods

mRNA expression levels of eight candidate marker genes - BIRC5, CCND1, CDH1, CITED1, DPP4, LGALS3, MET and TFF3 was measured by real-time RT-PCR in paired nodular and surrounding normal thyroid tissue specimens of 105 consecutive patients undergoing thyroid surgery and compared between different types of thyroid lesions.

Results

Significant differences in the mRNA expression levels between the normal and malignant thyroid tissues and between benign and malignant nodules were found for BIRC5, CCND1, CITED1, DPP4, LGALS3, MET and TFF3, but not CDH1. On a single gene basis, relative quantity (RQ) of LGALS3 had the highest diagnostic value for the discrimination of malignant and benign thyroid nodules (AUC = 0.832, P < 0.0001 and 90.9% sensitivity and 65.6% specificity at the optimal cut-off on ROC curve). The only two-marker set that outperformed LGALS3 was RQ sum of LGALS3 and BIRC5 (AUC = 0.841, P < 0.0001). An application of multivariate logistic regression analysis resulted in the generation of a multiplex biomarker model based on LGALS3, BIRC5, TFF3, CCND1, MET and CITED1 that had considerably higher specificity than a single marker or two marker gene-based models (AUC = 0.895, P < 0.0001, 70.5% sensitivity and 93.4% specificity).

Conclusions

This study confirmed that mRNA expression levels of 7 out of 8 candidate genes analysed have a diagnostic value for the distinction of benign and malignant thyroid nodules. The multiplex biomarker model based on 6 genes outperformed a single marker or two marker-based models and warrants feasibility studies on FNA biopsies and the validation in a larger cohort of patients.

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.

[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.

Identification of serum biomarkers for colorectal cancer metastasis using a differential secretome approach

Lymph node metastasis is the major concern that causes death in colorectal cancers. However, biomarkers for cancer metastasis are still lacking. In this study, we applied an LC-MS/MS-based label-free quantitative proteomics approach to compare the differential secretome of a primary cell line SW480 and its lymph node metastatic cell line SW620 from the same colorectal cancer patient. We identified a total of 910 proteins from the conditioned media and 145 differential proteins between SW480 and SW620 (>1.5-fold change). The differential expression pattern of 6 candidate proteins was validated by Western blot analysis. Among them, trefoil factor 3 and growth/differentiation factor 15, two up-regulated proteins in SW620, were further analyzed in a large cohort of clinical tissue and serum samples. Sandwich ELISA assay showed that the serum levels of both proteins were significantly higher in lymph node metastatic colorectal cancers. Receiver operating characteristic curve analysis confirmed that serum trefoil factor 3 and growth/differentiation factor 15 could provide a discriminatory diagnostic test for predicting colorectal cancer metastasis. Immunohistochemical analysis also showed that the overexpression of trefoil factor 3 or growth/differentiation factor 15 in colorectal cancer was associated with lymph node metastatic behavior. This study showed an accurate, sensitive, and robust label-free quantitation approach for differential analysis of cancer secretome. The comparison of the cancer secretome in vitro is a feasible strategy to obtain valuable biomarkers for potential clinical application. Both trefoil factor 3 and growth/differentiation factor 15 could serve as potential biomarkers for the prediction of colorectal cancer metastasis.

Differentiating the undifferentiated: immunohistochemical profile of medullary carcinoma of the colon with an emphasis on intestinal differentiation

Undifferentiated or medullary carcinoma is characterized by its distinct histologic appearance and relatively better prognosis compared to poorly differentiated colonic carcinoma. These 2 entities may be difficult to differentiate by light microscopy alone. Only limited immunohistochemical studies investigating medullary carcinoma have been reported. These studies suggest a loss of intestinal differentiation, exemplified by a high percentage of CDX2 negativity. Our aim was to further characterize the immunohistochemical profile of medullary carcinoma, with particular emphasis on intestinal markers. Paraffin blocks from 16 cases of medullary carcinoma and 33 cases of poorly differentiated colonic carcinoma were retrieved, and tissue microarrays were constructed and stained with an immunohistochemical panel including CDX2, CK7, CK20, p53, intestinal trefoil factor 3, chromogranin, synaptophysin, MLH-1, MUC-1, MUC-2, and calretinin. A significantly higher proportion of medullary carcinomas, as opposed to poorly differentiated colonic carcinomas, showed loss of staining for MLH-1 and for the intestinal transcription factor CDX2, in accordance with previous studies. MLH-1 staining was present in only 21% of medullary carcinoma cases compared with 60% of the poorly differentiated colonic carcinoma cases (P = .02), whereas CDX2 was positive in 19% of medullary carcinomas and 55% of poorly differentiated colonic carcinomas (P = .03). Interestingly, calretinin staining was strongly positive in 73% of medullary carcinomas compared to only 12% of poorly differentiated colonic carcinomas (P < .0001). Evidence of intestinal differentiation by MUC-1, MUC-2, and TFF-3 staining was seen in 67%, 60%, and 53% of the medullary carcinomas, respectively. These 3 markers were frequently positive in many of the CDX2-negative medullary carcinoma cases. Medullary carcinoma of the colon retains a significant degree of intestinal differentiation as evidenced by its high percentage of staining for MUC-1, MUC-2, and TFF-3. Calretinin, MLH-1, and CDX2 may help to differentiate medullary carcinoma from poorly differentiated colonic carcinoma of the colon.

Trefoil factor-3 expression in human colon cancer liver metastasis

Deaths from colorectal cancer are often due to liver metastasis. Trefoil factor-3 (TFF3) is expressed by normal intestinal epithelial cells and its expression is maintained throughout the colon adenoma-carcinoma sequence. Our previous work demonstrated a correlation between TFF3 expression and metastatic potential in an animal model of colon cancer. The aim of this study was to determine whether TFF3 is expressed in human colon cancer liver metastasis (CCLM) and whether inhibiting TFF3 expression in colon cancer cells would alter their invasive potential in vitro. Human CCLMs were analyzed at the mRNA and protein level for TFF3 expression. Two highly metastatic rat colon cancer cell lines that either natively express TFF3 (LN cells) or were transfected with TFF3 (LPCRI-2 cells), were treated with two rat TFF3 siRNA constructs (si78 and si365), and analyzed in an in vitro invasion assay. At the mRNA and protein level, TFF3 was expressed in 17/17 (100%) CCLMs and 10/11 (91%) primary colon cancers, but not in normal liver tissue. By real time PCR, TFF3 expression was markedly inhibited by both siRNA constructs in LN and LPCRI-2 cells. The si365 and si78 constructs inhibited invasion by 44% and 53%, respectively, in LN cells, and by 74% and 50%, respectively, in LPCRI-2 cells. These results provide further evidence that TFF3 contributes to the malignant behavior of colon cancer cells. These observations may have relevance for designing new diagnostic and treatment approaches to colorectal cancer.

HDAC3 overexpression and colon cancer cell proliferation and differentiation

An immunohistochemical analysis of human colorectal adenocarcinomas showed that cancer cells express widely varying levels of HDAC3. The SW480 colon cancer cell line was found to express high levels of HDAC3 compared to other colon cancer cell lines. p21 was poorly induced in SW480 cells relative to the lower HDAC3-expressing HT-29 cells. RNAi-induced reduction of HDAC3 in SW480 cells increased their constitutive, butyrate-, TSA-, and TNF-alpha-induced expression of p21, but did not cause all the gene expression changes induced upon general histone deacetylase (HDAC) inhibition. SW480 cells with lower HDAC3 expression appeared to be poised for gene expression responses with increased histone H4-K12 acetylation, but not K5, K8, or K16 acetylation. Even though p21 was readily activated in HT29 cells, HDAC3 siRNA nonetheless stimulated p21 expression in these cells to a greater degree than HDAC1 and HDAC2 siRNA. SW480 cells with lower HDAC3 levels displayed an enhanced cell cycle arrest and growth inhibition by butyrate, but without changes in apoptosis or sensitivity to chemotherapeutic agents. As reported for other colon cancer cell lines, butyrate induced the rapid downregulation of the secretory cell differentiation markers mucin 2 and intestinal trefoil factor in SW480 cells. Interestingly, selective HDAC3 inhibition was sufficient to downregulate these genes. Our data support a central role for HDAC3 in regulating the cell proliferation and differentiation of colon cancer cells and suggest a potential mechanism by which colon cancers may become resistant to luminal butyrate.

Predicting outcome in follicular lymphoma by using interactive gene pairs

PURPOSE

Follicular lymphoma is a common lymphoma of adults. Although its course is often indolent, a substantial proportion of patients have a poor prognosis, often due to rapid progression or transformation to a more aggressive lymphoma. Currently available clinical prognostic scores, such as the follicular lymphoma international prognostic index, are not able to optimally predict transformation or poor outcome.

EXPERIMENTAL DESIGN

Gene expression profiling was done on primary lymphoma biopsy samples.

RESULTS

Using a statistically conservative approach, predictive interaction analysis, we have identified pairs of interacting genes that predict poor outcome, measured as death within 5 years of diagnosis. The best gene pair performs >1,000-fold better than any single gene or the follicular lymphoma international prognostic index in our data set. Many gene pairs achieve outcome prediction accuracies exceeding 85% in extensive cross-validation and noise sensitivity computational analyses. Many genes repeatedly appear in top-ranking pairs, suggesting that they reproducibly provide predictive capability.

CONCLUSIONS

The evidence reported here may provide the basis for an expression-based, multi-gene test for predicting poor follicular lymphoma outcomes.

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.

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.

Physiological stress induces the metastasis marker AGR2 in breast cancer cells

As an approach to understanding the factors that activate expression of tumor progression genes, the role of physiological stress in the activation of a panel of tumor cell markers was investigated. These studies identify the developmental gene product, anterior gradient 2 (AGR2) as a cancer cell marker specifically up-regulated in response to depletion of serum and oxygen. AGR2 has been identified as a tumor marker in primary and secondary cancer lesions, and as a marker for detection of circulating tumor cells (CTCs). Elevated levels of AGR2 are known to increase the metastatic potential of cancer cells, but conditions leading to increased expression of AGR2 are not well understood. The present results identify novel physiological parameters likely to contribute to AGR2 induction in situ.

Induction of the adenoma-carcinoma progression and Cdc25A-B phosphatases by the trefoil factor TFF1 in human colon epithelial cells

TFF1 is overexpressed in inflammatory diseases and human cancers of the digestive and urogenital systems. To examine the transforming potential of TFF1 in human colon epithelial cells, premalignant PC/AA/C1 adenoma cells (PC) derived from a patient with familial adenomatous polyposis (FAP) were transformed by the TFF1 cDNA and used as a model of the adenoma-carcinoma transition. Constitutive expression of TFF1 increased anchorage-independent cell growth in soft agar, and induced or potentiated the growth of colon PC-TFF1 and kidney MDCKts.src-TFF1 tumor xenografts in athymic mice. This resulted in reduction of thapsigargin-induced apoptosis and promotion of collagen type I invasion through several oncogenic pathways. Using the differential display approach to identify TFF1 target genes, we found that the dual specific phosphatases Cdc25A and B implicated in cell cycle transitions are strongly upregulated under active forms in both PC-TFF1 and HCT8/S11-TFF1 colon cancer cells. Accordingly, TFF1 expression is absent in normal human colon crypts but is induced in correlation with Cdc25a and b transcript levels and tumor grade in familial and sporadic colon adenomas and carcinomas. We propose that TFF1 and Cdc25A-B cooperate with other dominant oncogenic pathways to induce the adenoma and adenocarcinoma transitions. Agents that target TFF1/Cdc25 signaling pathways may be useful for treating patients with TFF1-positive solid tumors.

Trefoil factor family-1 mutations enhance gastric cancer cell invasion through distinct signaling pathways

BACKGROUND & AIMS

Trefoil factor family-1 (TFF1) is a key gastric tumor-suppressor gene. TFF1 knockout mice develop multiple gastric adenomas and carcinomas, and human gastric cancers typically lack TFF1 expression. Recently, TFF1 mutations have been found in human gastric cancer. The purpose of this study was to determine the functionality of these mutants.

METHODS

Recombinant wild-type TFF1 and the gastric cancer-associated TFF1 mutants (A10D and E13K) were produced and tested for their effect on gastric cancer cell proliferation, apoptosis, and invasion. Molecular modeling was used to guide the choice of mutants and to evaluate structure-function relationships.

RESULTS

Molecular modeling suggested that A10D and E13K altered the surface charge of the loop 1 region of TFF1 without disturbing protein stability. Recombinant wild-type TFF1 significantly inhibited cell growth; A10D and E13K lost this tumor-suppressive property along with the ability to block etoposide-induced apoptosis. Although wild-type TFF1 promoted cell invasion, A10D and E13K were even more pro-invasive. Invasion induced by both mutants was blocked by inhibiting PI3-kinase or phospholipase-C, but inhibiting Rho-associated kinase (ROCK) blocked only E13K-induced invasion.

CONCLUSIONS

The loss of tumor-suppressor activity and gain of invasiveness from single point mutations constitute evidence for a functional role of TFF1 mutations in gastric cancer. These site-directed mutagenesis experiments provide the tools for continued probing of signal transduction mechanisms and structural elements responsible for TFF1 functions.

Specific gene expression profiles distinguish among functional allelic variants of the mouse Pthlh gene in transfected human cancer cells

The mouse parathyroid hormone-like hormone (Pthlh) gene encodes three allelic variants characterized by amino acid substitutions that are associated with susceptibility (Pthlh(Pro)) or resistance (Pthlh(Thr) and Pthlh(SerAspTyr)) to two-stage skin carcinogenesis and to modulation of cell migration in vitro in transfected human cancer cells. cDNA microarray hybridization analysis of 8473 transcript clones revealed a similar gene expression profile for the Pthlh(Thr) and Pthlh(SerAspTyr) alleles but a distinct pattern for the Pthlh(Pro) allele, suggesting an association between a specific gene expression profile and biological function of the Pthlh alleles. Some of the genes modulated by the Pthlh alleles, e.g., ANXA1, CCL2, FN1 and TFF3, play a role in cell migration and may represent candidate targets for this Pthlh function. Our study demonstrates the potential usefulness of gene expression profiling of genetic variants for the functional characterization of candidate cancer modifier genes.