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

Trefoil factor family proteins as potential diagnostic markers for mucinous invasive ovarian carcinoma

Introduction

Ovarian cancer (OC) is the leading cause of gynecological cancer-related death. Of the main OC histologic subtypes, invasive mucinous carcinomas (MC) account for only 3% of OC cases and are frequently associated with favorable prognosis. Nevertheless, MCs differ greatly from the other OC histotypes in clinical, pathological, and biological behavior. However, the origin and molecular pathogenesis of MC are not yet fully understood. Therefore, identification of novel diagnostic markers could potentially facilitate early diagnosis of OC, particularly the MC histotype, thereby leading to the development of histotype-specific treatment regimens and improved survival rates.

Methods

In the present study, Trefoil factor gene family members (TFF1, TFF2 and TFF3) were identified as MC histotype-specific biomarkers using RNA sequencing (RNA-seq) data for 95 stage I-II OCs. The diagnostic value of TFF1, TFF2 and TFF3 was then evaluated by immunohistochemistry on 206 stage I-II OCs stratified by histotype (high-grade serous carcinoma [HGSC], endometrioid carcinoma [EC], clear cell carcinoma [CCC], and MC).

Results

We showed significantly elevated intracytoplasmic protein expression levels for TFF1, TFF2 and TFF3 in MC samples, thereby revealing an association between expression of Trefoil factor gene family members and the MC histotype. Taken together, these findings suggest that the TFF proteins may play a pivotal role in tumor initiation and progression for the MC histotype.

Conclusion

Taken together, these findings suggest that the TFF proteins may play a pivotal role in tumor initiation and progression for the MC histotype. Moreover, these novel histotype-specific diagnostic biomarkers may not only improve patient stratification of early-stage ovarian carcinomas but may also be candidates for the development of molecular targeted therapies.

Monomerization of Homodimeric Trefoil Factor 3 (TFF3) by an Aminonitrile Compound Inhibits TFF3-Dependent Cancer Cell Survival

Trefoil factor 3 (TFF3) is a secreted protein with an established oncogenic function and a highly significant association with clinical progression of various human malignancies. Herein, a novel small molecule that specifically targets TFF3 homodimeric functions was identified. Utilizing the concept of reversible covalent interaction, 2-amino-4-(4-(6-fluoro-5-methylpyridin-3-yl)phenyl)-5-oxo-4H,5H-pyrano[3,2-c]chromene-3-carbonitrile (AMPC) was identified as a molecule that interacted with TFF3. AMPC monomerized the cellular and secreted TFF3 homodimer at the cysteine (Cys)57-Cys57 residue with subsequent more rapid degradation of the generated TFF3 monomers. Hence, AMPC treatment also resulted in cellular depletion of TFF3 with consequent decreased cell viability in various human carcinoma-derived TFF3 expressing cell lines, including estrogen receptor positive (ER+) mammary carcinoma (MC). AMPC treatment of TFF3 expressing ER+ MC cells significantly suppressed total cell number in a dose-dependent manner. Consistently, exposure of TFF3 expressing ER+ MC cells to AMPC decreased soft agar colony formation, foci formation, and growth in suspension culture and inhibited growth of preformed colonies in 3D Matrigel. AMPC increased apoptosis in TFF3 expressing ER+ MC cells associated with decreased activity of EGFR, p38, STAT3, AKT, and ERK, decreased protein levels of CCND1, CCNE1, BCL2, and BCL-XL, and increased protein levels of TP53, CDKN1A, CASP7, and CASP9. siRNA-mediated depletion of TFF3 expression in ER+ MC cells efficiently abrogated AMPC-stimulated loss of cell viability and CASPASE 3/7 activities. Furthermore, in mice bearing ER+ MC cell-generated xenografts, AMPC treatment significantly impeded xenograft growth. Hence, AMPC exemplifies a novel mechanism by which small molecule drugs may inhibit a dimeric oncogenic protein and provides a strategy to impede TFF3-dependent cancer progression.

Trefoil factor 3 promotes pancreatic carcinoma progression via WNT pathway activation mediated by enhanced WNT ligand expression

Pancreatic ductal adenocarcinoma (PDAC) is a major cause of cancer-related mortality with a dismal prognosis that has changed little over the past few decades. Further understanding of the molecular pathology of PDAC progression is urgently required in order to improve the prognosis of patients with PDAC. Herein, it was observed that trefoil factor 3 (TFF3) expression was elevated in PDAC, and was positively correlated with a worse overall patient survival outcome. Forced expression of TFF3 promoted oncogenic functions of PDAC cells in vitro including cell proliferation, survival, foci formation, cancer stem cell-like behavior and invasion, ex vivo colony growth in 3D-Matrigel, and xenograft growth in vivo. Depletion or pharmacological inhibition of TFF3 inhibited these same processes. RNA-Seq analysis and subsequent mechanistic analyses demonstrated that TFF3 increased the expression of various WNT ligands to mediate WNT pathway activation required for TFF3-stimulated PDAC progression. Combined pharmacological inhibition of TFF3 and WNT signaling significantly attenuated PDAC xenograft growth and potentiated the therapeutic efficacy of gemcitabine in both ex vivo and in vivo models. Hence, a mechanistic basis for combined inhibition of pathways enhancing PDAC progression is provided and suggests that inhibition of TFF3 may assist to ameliorate outcomes in PDAC.

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 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.

Exome sequencing in 51 early onset non-familial CRC cases

Background

Colorectal cancer (CRC) cases with an age of onset <40 years suggests a germline genetic cause. In total, 51 simplex cases were included to test the hypothesis of CRC as a mendelian trait caused by either heterozygous autosomal dominant or bi‐allelic autosomal recessive pathogenic variants.

Methods

The cohort was whole exome sequenced (WES) at 100× coverage. Both a dominant‐ and recessive model were used for searching predisposing genetic factors. In addition, we assayed recessive variants of potential moderate risk that were enriched in our young‐onset CRC cohort. Variants were filtered using a candidate cancer gene list or by selecting variants more likely to be pathogenic based on variant type (e.g., loss‐of‐function) or allele frequency.

Results

We identified one pathogenic variant in PTEN in a patient subsequently confirmed to have a hereditary hamartoma tumor syndrome (Cowden syndrome) and one patient with a pathogenic heterozygous variant in PMS2 that was originally not identified by WES due to low quality reads resulting from pseudogenes. In addition, we identified three heterozygous candidate missense variants in known cancer susceptibility genes (BMPR1A,BRIP1, and SRC), three truncating variants in possibly novel cancer genes (CLSPN,SEC24B, SSH2) and four candidate missense variants in ACACA, NR2C2, INPP4A, and DIDO1. We also identify five possible autosomal recessive candidate genes: ATP10B,PKHD1,UGGT2,MYH13,TFF3.

Conclusion

Two clear pathogenic variants were identified in patients that had not been identified clinically. Thus, the chance of detecting a hereditary cancer syndrome in patients with CRC at young age but without family history is 2/51 (4%) and therefore the clinical benefit of genetic testing in this patient group is low. Of note, using stringent filtering, we have identified a total of ten candidate heterozygous variants and five possibly biallelic autosomal recessive candidate genes that warrant further study.

Tumor suppressor miR-215 counteracts hypoxia-induced colon cancer stem cell activity

Cancer stem cells, also known as tumor-initiating cells (TICs), are a population of aggressive and self-renewing cells that are responsible for the initiation and progression of many cancers, including colorectal carcinoma. Intratumoral hypoxia, i.e. reduced oxygen supply following uncontrolled proliferation of cancer cells, is thought to support TIC activity by inducing specific hypoxia-responsive mechanisms that are not yet entirely understood. Using previously established and fully characterized patient-derived TIC cultures, we could observe increased sphere and colony formation under hypoxic conditions. Mechanistically, microRNA (miRNA)-profiling experiments allowed us to identify miR-215 as one of the main hypoxia-induced miRNAs in primary colon TICs. Through stable overexpression of miR-215, followed by a set of functional in vitro and in vivo investigations, miR-215 was pinpointed as a negative feedback regulator, working against the TIC-promoting effects of hypoxia. Furthermore, we could single out LGR5, a bona fide marker of non-neoplastic intestinal stem cells, as a downstream target of hypoxia/miR-215 signaling. The strong tumor- and TIC-suppressor potential of miR-215 and the regulatory role of the hypoxia/miR-215/LGR5 axis may thus represent interesting points of attack for the development of innovative anti-CSC therapy approaches.

TFF3 Contributes to Epithelial-Mesenchymal Transition (EMT) in Papillary Thyroid Carcinoma Cells via the MAPK/ERK Signaling Pathway

Trefoil factor 3 (TFF3) was found to be overexpressed in many types of tumours. Evidence has shown that TFF3 plays an important role in tumour proliferation, migration and invasion metastasis. However, the impact of TFF3 on patients' clinicopathological characteristics and underlying mechanisms remain unknown in papillary thyroid carcinoma (PTC). In this study, the expression of TFF3 and the epithelial-mesenchymal transition (EMT) transcriptional factor Snail in PTC and para-carcinoma specimens was evaluated by immunohistochemistry (IHC) and Western blot, and the possible associations with lymph node (LN) metastasis and other clinicopathological parameters were analysed. In vitro, the effect of TFF3 on the malignant behaviour of TPC-1 cells was evaluated by cell proliferation assays, cell adhesion assays, colony formation assays, wound-healing assays and transwell chamber invasion assays. EMT markers and regulatory molecules were detected by quantitative RT-PCR (qRT-PCR) and Western blot analysis in the TFF3-knockdown groups and shRNA control group. The results showed that TFF3 was upregulated in PTC tissue and was associated with lymph node metastasis (P=0.0001), pathological grade (P=0.0002) and Snail expression (P=0.0001). The knockdown of TFF3 markedly inhibited the abilities of TPC-1 cell proliferation, adhesion, colony formation, migration and invasion. Mechanically, the results demonstrated that TFF3 might activate the MAPK/ERK signalling pathways, affect the expression of the transcription factors snail and slug in addition to affecting EMT associated markers E-cadherin and N-cadherin, and accelerate the progression of EMT in TPC-1 cells. These findings indicate that TFF3 might promote the metastatic potential of PTC by promoting the EMT process through cascades of MAPK/ERK pathways.

Downregulation of trefoil factor-3 expression in the rectum is associated with the development of ulcerative colitis-associated cancer

Diagnostic markers facilitate more selective screening and treatment strategies for ulcerative colitis (UC)-associated cancer (UCAC). The expression of trefoil factor-3 (TFF3), which is involved in mucosal protection and repair in the gastrointestinal tract, was analyzed and its significance for UCAC was evaluated. A total of 145 patients with UC who underwent proctocolectomies were enrolled, including 15 patients (10.8%) with UCAC. TFF3 expression in the rectal mucosa and in cancer cells was assessed using immunohistochemistry, and the expression in UCAC and sporadic colorectal cancer was compared. Analyzing the mucinous granules of goblet cells located in crypts revealed that the non-cancerous rectal mucosa of patients with UCAC had significantly lower mean TFF3 staining scores compared with patients with UC without UCAC or patients with sporadic cancer. TFF3 staining score was revealed to be an independent predictor of UCAC development. These results indicated that low TFF3 expression in the rectal mucosa was associated with the development of UCAC. Thus, TFF3 expression in the rectal mucosa may be a useful biomarker for monitoring patients with UC.

Comprehensive Evaluation of TFF3 Promoter Hypomethylation and Molecular Biomarker Potential for Prostate Cancer Diagnosis and Prognosis

Overdiagnosis and overtreatment of clinically insignificant tumors remains a major problem in prostate cancer (PC) due to suboptimal diagnostic and prognostic tools. Thus, novel biomarkers are urgently needed. In this study, we investigated the biomarker potential of Trefoil factor 3 (TFF3) promoter methylation and RNA expression levels for PC. Initially, by quantitative methylation specific PCR (qMSP) analysis of a large radical prostatectomy (RP) cohort (n = 292), we found that the TFF3 promoter was significantly hypomethylated in PC compared to non-malignant (NM) prostate tissue samples (p < 0.001) with an AUC (area under the curve) of 0.908 by receiver operating characteristics (ROC) curve analysis. Moreover, significant TFF3 promoter hypomethylation (p ≤ 0.010) as well as overexpression (p < 0.001) was found in PC samples from another large independent patient sample set (498 PC vs. 67 NM) analyzed by Illumina 450K DNA methylation arrays and/or RNA sequencing. TFF3 promoter methylation and transcriptional expression levels were inversely correlated, suggesting that epigenetic mechanisms contribute to the regulation of gene activity. Furthermore, low TFF3 expression was significantly associated with high ERG, ETS transcription factor (ERG) expression (p < 0.001), as well as with high Gleason score (p < 0.001), advanced pathological T-stage (p < 0.001), and prostate-specific antigen (PSA) recurrence after RP (p = 0.013; univariate Cox regression analysis). There were no significant associations between TFF3 promoter methylation levels, ERG status, or PSA recurrence in these RP cohorts. In conclusion, our results demonstrated diagnostic biomarker potential of TFF3 promoter hypomethylation for PC as well as prognostic biomarker potential of TFF3 RNA expression. To the best of our knowledge, this is the most comprehensive study of TFF3 promoter methylation and transcriptional expression in PC to date.

Discovery and validation of a colorectal cancer classifier in a new blood test with improved performance for high-risk subjects

BACKGROUND

The aim was to improve upon an existing blood-based colorectal cancer (CRC) test directed to high-risk symptomatic patients, by developing a new CRC classifier to be used with a new test embodiment. The new test uses a robust assay format-electrochemiluminescence immunoassays-to quantify protein concentrations. The aim was achieved by building and validating a CRC classifier using concentration measures from a large sample set representing a true intent-to-test (ITT) symptomatic population.

METHODS

4435 patient samples were drawn from the Endoscopy II sample set. Samples were collected at seven hospitals across Denmark between 2010 and 2012 from subjects with symptoms of colorectal neoplasia. Colonoscopies revealed the presence or absence of CRC. 27 blood plasma proteins were selected as candidate biomarkers based on previous studies. Multiplexed electrochemiluminescence assays were used to measure the concentrations of these 27 proteins in all 4435 samples. 3066 patients were randomly assigned to the Discovery set, in which machine learning was used to build candidate classifiers. Some classifiers were refined by allowing up to a 25% indeterminate score range. The classifier with the best Discovery set performance was successfully validated in the separate Validation set, consisting of 1336 samples.

RESULTS

The final classifier was a logistic regression using ten predictors: eight proteins (A1AG, CEA, CO9, DPPIV, MIF, PKM2, SAA, TFRC), age, and gender. In validation, the indeterminate rate of the new panel was 23.2%, sensitivity/specificity was 0.80/0.83, PPV was 36.5%, and NPV was 97.1%.

CONCLUSIONS

The validated classifier serves as the basis of a new blood-based CRC test for symptomatic patients. The improved performance, resulting from robust concentration measures across a large sample set mirroring the ITT population, renders the new test the best available for this population. Results from a test using this classifier can help assess symptomatic patients' CRC risk, increase their colonoscopy compliance, and manage next steps in their care.

TFF3 Expression as Stratification Marker in Borderline Epithelial Tumors of the Ovary

Borderline tumors (BOT) of the ovary account for 10% to 20% of ovarian neoplasms. Like ovarian cancer, BOT encompass several different histological subtypes (serous, mucinous, endometrioid, clear cell, transitional cell and mixed) with serous (SBOT) and mucinous (MBOT) the most common. Current hypotheses suggest low-grade serous carcinoma may develop in a stepwise fashion from SBOT whereas the majority of high grade serous carcinomas develop rapidly presumably from inclusion cysts or ovarian surface epithelium. The pathogenesis of mucinous ovarian tumors is still puzzling. Molecular markers could help to better define relationships between such entities. Trefoil factor-3 (TFF3) is an estrogen-regulated gene associated with prognosis in different types of cancer. It has also been included in a recent marker panel predicting subtypes of ovarian carcinoma. We analyzed the expression of TFF3 by immunohistochemistry in a cohort of 137 BOT and its association with histopathological features. Overall expression rate of TFF3 was 21.9%. None of the BOT with serous and endometrioid histology displayed strong TFF3 expression. On the other hand, TFF3 was highly expressed in 61.4% of MBOT cases and 33.3% of BOT with mixed histology (P < 0.001) suggesting a potential function of the protein in that subtypes. Associations of TFF3 expression with FIGO stage and micropapillary pattern were significant in the overall cohort but confounded by their correlation with histological subtypes. The highly specific expression of TFF3 in MBOT may help to further clarify potential relationships of tumors with mucinous histology and warrants further studies.

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.

Trefoil factor 3 expression in epithelial ovarian cancer exerts a minor effect on clinicopathological parameters

The role of trefoil factor 3 (intestinal) (TFF3) has been analyzed in numerous cancers, such as breast and gastrointestinal cancer, and has been associated with poor prognosis. However, the role of TFF3 in ovarian cancers is not clear. Expression analysis of TFF3 in 91 ovarian cancer patients was performed by immunohistochemistry of primary paraffin-embedded tumor samples. The results were scored according to staining intensity and percentage of positive tumor cells resulting in an immune-reactive score (IRS) of 0-12. These results were correlated with clinicopathological characteristics and survival. TFF3 expression in our patient cohort exhibited a tendency towards improved overall and progression-free survival (PFS). In TFF3-positive serous and high-grade serous ovarian cancers, the median PFS was 27.6 months [95% confidence interval (CI): 0-55.7] vs. 15.2 months in TFF3-negative tumors (95% CI: 13.8-16.6) (P=0.183). The median overall survival was 53.9 months in TFF3-positive tumors (95% CI: Non-applicable) vs. 44.4 months in TFF3-negative cases (95% CI: 30.5-58.3) (P=0.36). TFF3 negativity was significantly associated with higher tumor grade (P=0.05). Based on our results, further studies are required in order to elucidate whether survival and chemosensitivity are affected by TFF3 expression in ovarian cancer.

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.