Trefoil factor 3: a novel serum marker identified by gene expression profiling in high-grade endometrial carcinomas

Small molecule inhibition of TFF3 overcomes tamoxifen resistance and enhances taxane efficacy in ER+ mammary carcinoma

Even though tamoxifen has significantly improved the survival of estrogen receptor positive (ER+) mammary carcinoma (MC) patients, the development of drug resistance with consequent disease recurrence has limited its therapeutic efficacy. Trefoil factor-3 (TFF3) has been previously reported to mediate anti-estrogen resistance in ER+MC. Herein, the efficacy of a small molecule inhibitor of TFF3 (AMPC) in enhancing sensitivity and mitigating acquired resistance to tamoxifen in ER+MC cells was investigated. AMPC induced apoptosis of tamoxifen-sensitive and resistant ER+MC cells and significantly reduced cell survival in 2D and 3D culture in vitro. In addition, AMPC reduced cancer stem cell (CSC)-like behavior in ER+MC cells in a BCL2-dependent manner. Synergistic effects of AMPC and tamoxifen were demonstrated in ER+MC cells and AMPC was observed to improve tamoxifen efficacy in tamoxifen-sensitive cells and to re-sensitize cells to tamoxifen in tamoxifen-resistant ER+MC in vitro and in vivo. Additionally, tamoxifen-resistant ER+MC cells were concomitantly resistant to anthracycline, platinum and fluoropyrimidine drugs, but not to Taxanes. Taxane treatment of tamoxifen-sensitive and resistant ER+MC cells increased TFF3 expression indicating a combination vulnerability for tamoxifen-resistant ER+MC cells. Taxanes increased CSC-like behavior of tamoxifen-sensitive and resistant ER+MC cells which was reduced by AMPC treatment. Taxanes synergized with AMPC to promote apoptosis and reduce CSC-like behavior in vitro and in vivo. Hence, AMPC restored the sensitivity of tamoxifen and enhanced the efficacy of Taxanes in tamoxifen-resistant ER+MC. In conclusion, pharmacological inhibition of TFF3 may serve as an effective combinatorial therapeutic strategy for the treatment of tamoxifen-resistant ER+MC.

TFF3 as a Diagnostic Biomarker in Kidney Transplant Patients

Intestinal trefoil factor 3 (TFF3) is a protein secreted by many cell types, and its serum and urine levels vary in patients with kidney disease. Therefore, the present study aimed to determine the diagnostic value of TFF3 in allogeneic kidney transplant patients included in the one-year follow-up. To analyze the influence of the diagnostic method used, we studied the type of biological material and the time elapsed since renal transplantation on the parameter's value. The study also aimed to investigate the relationship between TFF3 levels and creatinine and estimated glomerular filtration rate (eGFR) values in the serum and urine of the patients studied. The study used blood and urine samples from adult patients (n = 19) 24-48 h, 6 months, and 12 months after kidney transplantation. We collected one-time blood and urine from healthy subjects (n = 5) without renal disease. We applied immunoenzymatic ELISA and xMap Luminex flow fluorimetry to determine TFF3 in serum and urine. There was a significant difference in TFF3 levels in the serum of patients collected on the first one or two days after kidney transplantation compared to the control group (determined by ELISA and Luminex) and six months and one year after kidney transplantation (ELISA). We observed a correlation between creatinine concentration and urinary TFF3 concentration (ELISA and Luminex) and a negative association between eGFR and urinary (ELISA) and serum (Luminex) TFF3 concentration in patients on the first and second days after kidney transplantation. We noted significant correlations between eGFR and TFF3 levels in the serum and urine of patients determined by the two methods six months and one year after transplantation. In women, we observed that urinary TFF3 concentration increased significantly with increasing creatinine and that with increasing eGFR, urinary TFF3 concentration determined by two methods decreased significantly. In the present study, the choice of diagnostic method for the determination of TFF3 in serum and urine significantly affected the concentration of this biomarker. The values of this parameter determined by ELISA were higher than those assessed using the Luminex assay. Based on the presented results, we can conclude that TFF3 has great potential to monitor renal transplant patients. Determination of this protein in parallel with creatinine and eGFR levels in serum and urine may provide helpful diagnostic information.

Diagnostic utility of trefoil factor families for the early detection of lung cancer and their correlation with tissue expression

Trefoil factors (TFFs) are upregulated in numerous types of cancer, including those of the breast, the colon, the lung and the pancreas, suggesting their potential utility as biomarkers for screening. In the present study, the clinical relevance of serum or urinary TFFs as biomarkers were comprehensively evaluated and the correlation with TFF expression levels in lung cancer tissue was examined. Serum and urine were collected from 199 patients with lung cancer and 198 healthy individuals. Concentrations of serum and urinary TFF1, TFF2 and TFF3 were measured using ELISA and the potential of TFF levels to discriminate between cancer and non-cancer samples was evaluated. In 100 of the cancer cases, expression of TFF1-3 was analyzed using immunohistochemical staining of paraffin sections. Furthermore, the relationship between TFF levels and clinicopathological factors among these cancer cases was analyzed using immunohistochemistry of tissue specimens, quantified and statistically analyzed. While serum levels of all TFFs measured using ELISA were significantly higher in patients with lung cancer compared with those in healthy individuals, urinary TFFs were lower. Areas under the curve (AUC) of the receiver operating characteristic curves for serum/urinary TFF1, TFF2 and TFF3 were 0.709/0.594, 0.722/0.501 and 0.663/0.665, respectively. Furthermore, the combination of serum TFF1, TFF2, TFF3 and urinary TFF1 and TFF3 demonstrated the highest AUC (0.826). In the clinicopathological analysis, serum TFF1 was higher in the early pathological T-stage (pTis/1/2) compared with the later stage (pT3/4) and TFF2 was higher in the pN0/1 than the pN2 group. With regards to the histological types, urinary TFF1 was higher in squamous cell carcinoma than adenocarcinoma (AC), but TFF2 tended to be higher in AC. Using immunohistochemical analysis, although TFF1 and TFF3 expression showed positive correlation with serum concentrations, TFF2 was inversely correlated. In conclusion, serum and urinary TFF levels are promising predictive biomarkers, and their measurements provide a useful in vivo and non-invasive diagnostic screening tool. In particular, TFF1 and TFF3 could be surrogate markers of clinicopathological profiles of human lung cancer.

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.

Diagnostic and prognostic role of TFF3, Romo-1, NF-кB and SFRP4 as biomarkers for endometrial and ovarian cancers: a prospective observational translational study

Purpose

This study aimed to evaluate trefoil factor 3 (TFF3), secreted frizzled-related protein 4 (sFRP4), reactive oxygen species modulator 1 (Romo1) and nuclear factor kappa B (NF-κB) as diagnostic and prognostic markers of endometrial cancer (EC) and ovarian cancer (OC).

Methods

Thirty-one patients with EC and 30 patients with OC undergone surgical treatment were enrolled together with 30 healthy controls in a prospective study. Commercial ELISA kits determined serum TFF-3, Romo-1, NF-кB and sFRP-4 concentrations.

Results

Serum TFF-3, Romo-1 and NF-кB levels were significantly higher in patients with EC and OC than those without cancer. Regarding EC, none of the serum biomarkers differs significantly between endometrial and non-endometrioid endometrial carcinomas. Mean serum TFF-3 and NF-кB levels were significantly higher in advanced stages. Increased serum levels of TFF-3 and NF-кB were found in those with a higher grade of the disease. Regarding OC, none of the serum biomarkers differed significantly among histological subtypes. Significantly increased serum levels of NF-кB were observed in patients with advanced-stage OC than those with stage I and II diseases. No difference in serum biomarker levels was found between those who had a recurrence and those who had not. The sensibility and specificity of these four biomarkers in discriminating EC and OC from the control group showed encouraging values, although no one reached 70%.

Conclusions

TFF-3, Romo-1, NF-кB and SFRP4 could represent new diagnostic and prognostic markers for OC and EC. Further studies are needed to validate our results.

Dissection of gene expression datasets into clinically relevant interaction signatures via high-dimensional correlation maximization

Gene expression is controlled by many simultaneous interactions, frequently measured collectively in biology and medicine by high-throughput technologies. It is a highly challenging task to infer from these data the generating effects and cooperating genes. Here, we present an unsupervised hypothesis-generating learning concept termed signal dissection by correlation maximization (SDCM) that dissects large high-dimensional datasets into signatures. Each signature captures a particular signal pattern that was consistently observed for multiple genes and samples, likely caused by the same underlying interaction. A key difference to other methods is our flexible nonlinear signal superposition model, combined with a precise regression technique. Analyzing gene expression of diffuse large B-cell lymphoma, our method discovers previously unidentified signatures that reveal significant differences in patient survival. These signatures are more predictive than those from various methods used for comparison and robustly validate across technological platforms. This implies highly specific extraction of clinically relevant gene interactions.

Identification of clinically relevant gene expression signatures for cancer stratification remains challenging. Here, the authors introduce a flexible nonlinear signal superposition model that enables dissection of large gene expression data sets into signatures and extraction of gene interactions.

Prognostic Value of Trefoil Factor 3 Expression in Patients with Gastric Cancer

BACKGROUND

Trefoil factor 3 (TFF3) is a small molecule secreted by the mammalian gastrointestinal tract and is overexpressed in some human malignant tumors. We investigated the prognostic values of immunohistochemical (IHC) TFF3 expression and serum TFF3 levels in patients with gastric cancer, and whether TFF3 influenced tumor proliferation and invasion in vitro.

METHODS

We examined 111 patients who underwent R0 gastrectomy for gastric cancer between April 2012 and April 2015. IHC TFF3 expression and serum TFF3 levels were evaluated regarding their associations with clinicopathological factors and recurrence-free survival (RFS). In vitro cell proliferation and migration assays were used to explore the biological role of TFF3 in human gastric cancer cell lines following transfection with a lentivirus-based shRNA plasmid.

RESULTS

IHC TFF3 expression showed significant associations with depth of invasion (p = 0.024), lymph node metastasis (p = 0.008), and RFS (log-rank p = 0.002). Serum TFF3 levels were correlated with IHC TFF3 expression (p = 0.013). RFS was significantly poorer in patients with high (n = 27) compared to low (n = 84) serum TFF3 levels (log-rank p = 0.003). Cox multivariate analysis indicated that serum TFF3 level was an independent prognostic factor for RFS (p = 0.024). In vitro assays, TFF3 downregulation significantly inhibited both proliferation and invasion of gastric cancer cells.

CONCLUSIONS

Serum TFF3 levels could be useful prognostic markers in patients with gastric cancer. TFF3 may play various biological roles in proliferation and invasion of gastric cancer cells.

Serum concentrations of TFF3, S100-A11 and AIF-1 in association with systemic inflammatory response, disease stage and nodal involvement in endometrial cancer

To compare preoperative intestinal trefoil factor 3 (TFF3), allograft inflammatory factor-1 (AIF-1) and calgizzarin (S100-A11) serum levels in patients with endometrial cancer, endometrial hyperplasia and in healthy female controls. Serum levels of TFF3, S100- A11 and AIP-1 were analyzed in 98 consecutive patients with histologically verified endometrial cancer, in 43 patients with endometrial hyperplasia diagnosed during hysteroscopy and 24 controls with benign disease. Results were correlated with urinary neopterin/creatinine ratio, serum kynurenine, tryptophan, retinol, alpha-tocopherol, vitamin D, citrulline, C-reactive protein, interleukin-6 and clinical characteristics. S100-A11, and AIF-1 levels were higher in endometrial hyperplasia patients than in controls, and also significantly higher in endometrial cancer than in patients with endometrial hyperplasia. Serum concentrations of TFF3 and S100-A11 were associated with tumor stage and lymph node status. TFF3 exhibited positive correlation with age, IL-6, vitamin D, kynurenine, urinary neopterin/creatinine ratio and kynurenine/tryptophan ratio. S100-A11, as well as AIF-1 correlated positively with Il-6 and TFF3. TFF3, S100-A11 and AIF-1 represent potential biomarkers in patients with endometrial cancer. TFF3 and S100-A11 increase with tumor stage and lymph node involvement, reflecting higher tumor mass that is also associated with increased concentration of biomarkers of immune dysfunction.

Hypomethylation associated enhanced transcription of trefoil factor-3 mediates tamoxifen-stimulated oncogenicity of ER+ endometrial carcinoma cells

Tamoxifen (TAM) is widely used as an adjuvant therapy for women with breast cancer (BC). However, TAM possesses partial oestrogenic activity in the uterus and its use has been associated with an increased incidence of endometrial carcinoma (EC). The molecular mechanism for these observations is not well understood. Herein, we demonstrated that forced expression of Trefoil factor 3 (TFF3), in oestrogen receptor-positive (ER+) EC cells significantly increased cell cycle progression, cell survival, anchorage-independent growth, invasiveness and tumour growth in xenograft models. Clinically, elevated TFF3 protein expression was observed in EC compared with normal endometrial tissue, and its increased expression in EC was significantly associated with myometrial invasion. TAM exposure increased expression of TFF3 in ER+ EC cells and its elevated expression resulted in increased oncogenicity and invasiveness. TAM-stimulated expression of TFF3 in EC cells was associated with hypomethylation of the TFF3 promoter sequence and c-JUN/SP1-dependent transcriptional activation. In addition, small interfering (si) RNA-mediated depletion or polyclonal antibody inhibition of TFF3 significantly abrogated oncogenicity and invasiveness in EC cells consequent to TAM induction or forced expression of TFF3. Hence, TAM-stimulated upregulation of TFF3 in EC cells was critical in promoting EC progression associated with TAM treatment. Importantly, inhibition of TFF3 function might be an attractive molecular modality to abrogate the stimulatory effects of TAM on endometrial tissue and to limit the progression of EC.

Quantitative electrochemical metalloimmunoassay for TFF3 in urine using a paper analytical device

We report a paper-based assay platform for the detection of the kidney disease marker Trefoil Factor 3 (TFF3) in human urine. The sensor is based on a quantitative metalloimmunoassay that can determine TFF3 concentrations via electrochemical detection of environmentally stable silver nanoparticle (AgNP) labels attached to magnetic microbeads via a TFF3 immunosandwich. The paper electroanalytical device incorporates two preconcentration steps that make it possible to detect concentrations of TFF3 in human urine at the low end of the target TFF3 concentration range (0.03-7.0 μg mL(-1)). Importantly, the paper device provides a level of accuracy for TFF3 determination in human urine equivalent to that of a commercial kit. The paper sensor has a dynamic range of ∼2.5 orders of magnitude, only requires a simple, one-step incubation protocol, and is fast, requiring only 10 min to complete. The cost of the materials at the prototypic laboratory scale, excluding reagents, is just US$0.42.

Serum Trefoil Factor 3 as a Protein Biomarker for the Diagnosis of Colorectal Cancer

Colorectal cancer is one of the most frequent causes of cancer-related deaths worldwide. Thus, there is a need for timely diagnosis and effective treatment. Our aim in the present study was to detect the serum level of trefoil factor 3 protein and evaluate the diagnostic accuracy of trefoil factor 3 in patients with colorectal cancer. We collected serum samples from 204 participants (127 patients with colorectal cancer, 35 patients with polyps, and 42 healthy controls). The levels of serum trefoil factor 3 and carcinoembryonic antigen expression were measured by enzyme-linked immunosorbent assay. Receiver operating characteristic curves were plotted to calculate the diagnostic accuracy of trefoil factor 3 in patients with colorectal cancer. The serum levels of trefoil factor 3 in patients with colorectal cancer (6.66 ± 2.4 ng/mL; P < .00l) and polyps (3.86 ± 1.3 ng/mL; P < .00l) were significantly increased compared to healthy controls (2.09 ± 1.0 ng/mL). Moreover, the area under the receiver operating characteristic curve for trefoil factor 3 was greater than carcinoembryonic antigen (0.889 vs 0.715). At a cutoff value of 5.591 ng/mL, the diagnostic sensitivity, specificity, and likelihood ratio of serum trefoil factor 3 for colorectal cancer was 74.2%, 94.8%, and 14.25, respectively. Furthermore, the serum trefoil factor 3 levels in early colorectal cancer (TNM stage I, 3.67 ± 1.27 ng/mL) were significantly increased compared to healthy controls ( P < .001); however, there was no significant difference compared to patients with polyps ( P = .576). We observed that the serum trefoil factor 3 levels decreased after surgery (6.66 ± 2.4 vs 4.48 ± 1.80 ng/mL; P < .001). In addition, high serum trefoil factor 3 levels were associated with poor tumor differentiation and clinical TNM stage ( P < .05). In conclusion, serum trefoil factor 3 is a promising biomarker for the diagnosis of colorectal cancer and prognosis of patients.

Neuropeptide Trefoil Factor 3 Reverses Depressive-Like Behaviors by Activation of BDNF-ERK-CREB Signaling in Olfactory Bulbectomized Rats

The trefoil factors (TFFs) are a family of three polypeptides, among which TFF1 and TFF3 are widely distributed in the central nervous system. Our previous study indicated that TFF3 was a potential rapid-onset antidepressant as it reversed the depressive-like behaviors induced by acute or chronic mild stress. In order to further identify the antidepressant-like effect of TFF3, we applied an olfactory bulbectomy (OB), a classic animal model of depression, in the present study. To elucidate the mechanism underlying the antidepressant-like activity of TFF3, we tested the role of brain-derived neurotrophic factor (BDNF)-extracellular signal-related kinase (ERK)-cyclic adenosine monophosphate response element binding protein (CREB) signaling in the hippocampus in the process. Chronic systemic administration of TFF3 (0.1 mg/kg, i.p.) for seven days not only produced a significant antidepressant-like efficacy in the OB paradigm, but also restored the expression of BDNF, pERK, and pCREB in the hippocampal CA3. Inhibition of BDNF or extracellular signal-related kinase (ERK) signaling in CA3 blocked the antidepressant-like activity of TFF3 in OB rats. Our findings further confirmed the therapeutic effect of TFF3 against depression and suggested that the normalization of the BDNF-ERK-CREB pathway was involved in the behavioral response of TFF3 for the treatment of depression.

Trefoil factors: Gastrointestinal-specific proteins associated with gastric cancer

Trefoil factor family (TFF), composed of TFF1, TFF2, and TFF3, is a cluster of secreted peptides characterized by trefoil domain (s) and C-terminal dimerization domain. TFF1, a gastric tumor suppressor, is a single trefoil peptide originally detected in breast cancer cell lines but expressed mainly in the stomach; TFF2, a candidate of gastric cancer suppressor with two trefoil domains, is abundant in the stomach and duodenal Brunner's glands; and TFF3 is another single trefoil peptide expressed throughout the intestine which can promote the development of gastric carcinoma. According to multiple studies, TFFs play a regulatory function in the mammals' digestive system, namely in mucosal protection and epithelial cell reconstruction, tumor suppression or promotion, signal transduction and the regulation of proliferation and apoptosis. Action mechanisms of TFFs remain unresolved, but the recent demonstration of a GKN (gastrokine) 2-TFF1 heterodimer implicates structural and functional interplay with gastrokines. This review aims to encapsulate the structural and biological characteristics of TFF.

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

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

Association between trefoil factor 3 gene variants and idiopathic recurrent spontaneous abortion

Trefoil factor 3 (TFF3) gene is an inflammatory mediator expressed in human endometrium during the window of implantation. The aim of this study was to evaluate the possible genetic association of TFF3 variants in recurrent spontaneous abortion. Women with a history of recurrent spontaneous abortion (n = 164) and healthy pregnant women (n = 143) were genotyped for five TFF3 polymorphisms (rs225439 G/A, rs533093 C/T, rs225361 A/G, rs11701143 T/C and rs77436142 G/C). In addition, haplotypes formed within the gene were analysed. Within the recurrent spontaneous abortion group, women who at some point had given birth and childless women had 4.19 ± 1.75 and 5.34 ± 3.42 consecutive spontaneous abortions, respectively. Women who had experience recurrent spontaneous abortions had a lower allele frequency of the rs11701143 promoter region minor C allele compared with fertile women (0.02 versus 0.05, P = 0.015). Patients with rs225361 AG genotype had significantly more successful pregnancies before spontaneous abortion than those with homozygous AA and GG genotypes (P = 0.014). No significant differences in haplotype frequencies between patients and controls were detected. Possible genetic risk factors identified that might contribute to the pathogenesis of idiopathic recurrent spontaneous abortion were TFF3 gene variants.

Serum TFF3 may be a pharamcodynamic marker of responses to chemotherapy in gastrointestinal cancers

BACKGROUND

As a secreted protein, serum trefoil factor 3 (TFF3) has been reported to be a biomarker of several malignancies. We further investigated whether TFF3 can be applied as a biomarker for and predictor of responses to chemotherapy in gastrointestinal cancer.

METHODS

Serum and urine samples were collected from 90 patients with gastric cancer, 128 patients with colorectal cancer and 91 healthy individuals. Serum and urine TFF3 levels were measured using an ELISA.

RESULTS

Serum and urine TFF3 levels were significantly higher in the patients with gastric and colorectal cancer compared with the healthy individuals (P < 0.05). Higher serum levels of TFF3 were significantly correlated with distant metastasis and an advanced stage in the two types of cancer (P < 0.05). Age and the number of lymph node metastases were significantly correlated with serum TFF3 levels in colorectal cancer, and decreased serum TFF3 levels were significantly correlated with responses to chemotherapy in both the gastric and the colorectal cancer partial response (PR) groups. A combination of serum and urine data did not significantly improve the detection of either cancer, although urine levels have shown a significant negative relationship with the glomerular filtration rate (GFR).

CONCLUSIONS

Our data indicate that TFF3 may be an effective biomarker of tumor stage and the presence of distant metastasis, and may be a pharmacodynamic marker of response to chemotherapy in gastrointestinal cancer.

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.

Impact of NPM, TFF3 and TACC1 on the prognosis of patients with primary gastric cancer

Background

NPM, TFF3 and TACC1 are molecular markers that play important roles in cell differentiation. Herein, we investigated their prognostic impact in patients with primary gastric cancer (GC) and determined whether they could be used as markers of more aggressive gastric carcinomas by detecting the extent of expression in human gastric carcinoma samples.

Methodology/Principal Findings

Tumor tissue specimens from 142 GC patients were retrospectively retrieved and immunohistochemically evaluated. Correlations between NPM, TFF3 and TACC1 over-expression and clincopathologic parameters, and their prognostic values were investigated with χ², Kaplan-Meier method, and Cox uni- and multivariate survival models. NPM, TFF3 and TACC1 expression was significantly higher in GC patients with poorly differentiated histologic type than that in patients with well differentiated histologic type. NPM expression was significantly higher in patients with hepatic metastasis or recurrence than that in patients without metastasis. TFF3 expression was significantly higher in patients with positive lymph node metastasis than that in patients with negative lymph node metastasis. Age, lymph node metastasis, and TFF3 and TACC1 over-expression were significantly correlated with low survival (P<0.05, P<0.05, P = 0.005 and P = 0.009, respectively). Multivariate analysis showed that lymph node metastasis and TFF3 and TACC1 over-expression were independent prognostic factors.

Conclusions

TFF3 and TACC1 over-expression in epithelial cells of surgically resected GC tissues was an independent predictor of short survival in GC patients. The prognosis was poorer in patients with positive expression of both TFF3 and TACC1 than that in patients with positive expression of TFF3 or TACC1 alone, or with negative expression of TFF3 and TACC1.

Circulating serum trefoil factor 3 (TFF3) is dramatically increased in chronic kidney disease

Objectives

Trefoil factor 3 (TFF3) is a small peptide that plays an important role in mucosal protection, cell proliferation, and cell migration. The aberrant expression of TFF3 is correlated with gastrointestinal inflammation, solid tumors, and other clinical diseases. The objective of this study was to identify the distribution characteristics of serum TFF3 in common clinical diseases.

Materials and Methods

A large prospective randomized study of 1,072 Chinese patients was performed using an enzyme-linked immunosorbent assay (ELISA) to examine the serum TFF3 concentrations in patients with different diseases. A matched case-control study was conducted on patients with chronic kidney disease (CKD) stages 1–5. Immunohistochemistry (IHC) was performed using renal tissues to determine the relationship between the severity of CKD and the serum and urine concentrations of TFF3 peptides.

Results

The mean serum concentrations of TFF3 in patients with CKD, metastatic and secondary carcinoma (MC) and acute gastroenteritis (AG) (200.9 ng/ml, 95.7 ng/ml and 71.7 ng/ml, respectively) were significantly higher than those in patients with other common clinical diseases. A positive correlation tendency was observed between the serum TFF3 concentrations and the severity of CKD. The mean serum TFF3 values for CKD stages 1–5 were 23.6 ng/ml, 29.9 ng/ml, 54.9 ng/ml, 85.0 ng/ml and 176.6 ng/ml, respectively. The same trend was observed in the urine TFF3 concentrations and the CKD stages. The creatinine(Cr)-corrected concentrations of TFF3 in urine were 367.1 ng/mg·Cr, 910.6 ng/mg·Cr, 1,149.0 ng/mg·Cr, 1,610.0 ng/mg·Cr and 3,475.0 ng/mg·Cr for CKD stages 1–5, respectively. IHC revealed that TFF3 expression was concentrated in tubular epithelial cells.

Conclusions

The influence of kidney injuries must be fully considered when performing clinical TFF3 research. Further studies on TFF3 in CKD will contribute to our understanding of its pathological roles and mechanisms in other diseases.

The association of trefoil factor 3 gene polymorphisms and haplotypes with unexplained female infertility: molecular insights into TFF3 regulation in receptive phase endometrium

Abstract This study examined the genetic variation within the gene trefoil factor 3 (TFF3) in relation to unexplained female infertility in a group of women where aberrant endometrial maturation was suspected. The study consisted of 113 women with a diagnosis of unexplained infertility and 289 healthy fertile volunteers. Five single nucleotide polymorphisms rs225439, rs533093, rs225361, rs11701143, and rs77436142 within TFF3 gene were analyzed using real-time PCR. The formed haplotype pattern within the TFF3 gene in relation to infertility was also assessed. TFF3 protein localization and expression in receptive stage endometrium at the time of implantation was measured in a subset of fertile (n = 7) and infertile (n = 12) women. Allele and genotype frequencies did not differ significantly between fertile and infertile women, nor did the formed haplotypes. TFF3 protein was expressed in all cell types in receptive stage endometria in fertile and infertile women. No significant association was observed between protein expression and analyzed genotypes. A significantly higher TFF3 expression in luminal epithelial cells was detected in women with unexplained infertility (p = 0.003).

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.

Influence of Helicobacter pylori status and eradication on the serum levels of trefoil factors and pepsinogen test: serum trefoil factor 3 is a stable biomarker

BACKGROUND AND AIM

Emerging data indicate that serum trefoil factors (TFFs), especially TFF3, could be potential biomarkers for gastric cancer risk. We aimed to evaluate the influence of Helicobacter pylori (H. pylori) status and eradication on serum TFFs and the pepsinogen test.

METHODS

Healthy individuals who underwent a thorough medical checkup were enrolled in study 1, and gastric ulcer patients who undertook H. pylori eradication therapy were enrolled in studies 2 and 3. Serum levels of the TFFs (TFF1, TFF2 and TFF3), H. pylori antibody and pepsinogen test were examined in all studies. In study 3, TFF expressions in biopsy samples of the gastric mucosa were additionally examined before and 2 months after eradication.

RESULTS

In 1,260 healthy individuals enrolled in study 1, serum TFF1 and TFF2 levels were markedly different between H. pylori antibody-positive and -negative participants (P < 0.0001). Differences in serum TFF3 levels between H. pylori antibody-positive (5.85 ± 3.93 ng/ml) and -negative subjects (5.27 ± 2.38 ng/ml) were statistically significant (P = 0.002) but small in absolute value. In 178 gastric ulcer patients enrolled in study 2, serum TFF1, TFF2 and positive rates of the pepsinogen test significantly decreased 2 months after H. pylori eradication therapy (P < 0.001). In contrast, serum TFF3 levels and positive rates of high TFF3 levels (≥7 ng/ml) did not significantly change with H. pylori-eradication until 5 years after eradication. In 18 gastric ulcer patients (study 3), TFF1 and TFF2 were mainly expressed in the foveolar epithelium, and TFF2 was additionally expressed in the pyloric glands. These expressions significantly decreased with H. pylori eradication. TFF3s were scarcely expressed in the gastric mucosa except in goblet cells of intestinal metaplasia, which did not change with H. pylori eradication.

CONCLUSION

In serum TFFs and pepsinogen tests, only serum TFF3s were not significantly affected by H. pylori eradication, suggesting that serum TFF3 could be a stable biomarker of gastric cancer risk even after H.pylori eradication in contrast with the pepsinogen test.

ER+ /PR+ /TFF3+ /IMP3- immunoprofile distinguishes endometrioid from serous and clear cell carcinomas of the endometrium: a study of 401 cases

AIMS

Differentiating endometrioid adenocarcinoma (EAC) from uterine serous carcinoma (USC) and clear cell carcinoma (CCC) of the endometrium can be challenging. We undertook an immunohistochemical study to address this issue.

METHODS AND RESULTS

We evaluated 401 endometrial carcinomas cases by using four immunomarkers - oestrogen receptor (ER), progesterone receptor (PR), insulin-like growth factor II mRNA - binding protein 3 (IMP3), and intestinal trefoil factor 3 (TFF3)-on a tissue microarray. The cases included 311 EACs (G1, 146; G2, 104; and G3, 61), 69 USCs, and 21 CCCs. ER, PR and TFF3 were most frequently expressed in EACs (P < 0.001), and IMP3 was more frequently expressed in USCs and CCCs (P < 0.001). ER(+) /PR(+) /TFF3(+) /IMP3(-) was the best marker combination associated with EAC [exact odds ratio (OR) 112; 95% confidence interval (CI) 19-∞; P < 0.0001]. This marker combination remained very reliable after adjustment for tumour grade (exact OR 19.2; 95% CI 3-∞; P = 0.0004). Because distinguishing EAC G3 from USC and CCC on the basis of morphology may be difficult, the use of immunomarkers to improve reproducibility is highly recommended. We found the ER(+) /PR(+) /TFF3(+) /IMP3(-) immunoprofile to be the best combination for confirming a diagnosis of endometrioid adenocarcinoma (exact OR 19.2; 95% CI 3-∞; P = 0.0004).

CONCLUSIONS

We recommend using an ER/PR/TFF3/IMP3 immunohistochemical panel in selected cases of endometrial carcinoma where the differential diagnosis is challenging.

Trefoil factor family 3 (TFF3) expression and its interaction with estrogen receptor (ER) in endometrial adenocarcinoma

OBJECTIVES

TFF3 has been found to be up-regulated at the gene and protein levels in endometrioid adenocarcinoma (EAC) when compared to uterine serous carcinoma (USC) and normal endometrium. In addition, TFF3 has been proven to be an estrogen-responsive gene and its expression level positively correlated to estrogen-receptor (ER) status in breast cancer cell culture. The aims of this study are to determine the expression and the prognostic value of TFF3 in a large series of human endometrial cancer and its relation with ER.

METHODS

We evaluated 328 endometrial carcinomas using TFF3 and ER antibody on paraffin-embedded tissue. 74% were type I (EAC), and 26% were type II (USC, CCC and carcinosarcoma).

RESULTS

In type I carcinomas, TFF3(+) expression was associated with no lympho-vascular invasion (p=0.0131), disease status (p=0.0132), recurrence-free survival (p=0.0424) and overall survival (p=0.0018). There was a positive association between TFF3 and ER (p<.0001). The combination of TFF3(+)/ER(+) was associated with low FIGO grade (p=.0122), early FIGO stage (p=.0062), absence of recurrence (p=.0037), absence of LVI (p=.0011), no lymph node involvement (p=.0116) and disease status (p=.0107). TFF3 appeared to be an independent prognostic marker in predicting recurrences (p=.046). In type II carcinomas, TFF3 failed to have a prognostic value.

CONCLUSION

1-TFF3 seems to be a novel pathway in the pathogenesis of type I endometrial carcinomas. 2-The strong association of TFF3 and ER in the estrogen-dependent endometrioid carcinoma could explain the reason for its frequent expression by this tumor type. 3-TFF3(+) seems to forecast a good prognosis in type I endometrial carcinomas. Based on our data, TFF3 expression in endometrial cancer deserves further investigation.

Quantitative measurements of trefoil factor family peptides: possibilities and pitfalls

The trefoil factor family (TFF) peptides TFF1, TFF2, and TFF3 are produced and secreted by mucous membranes throughout the body. Their importance for the protection and repair of epithelial surfaces is well established, and the three peptides are present in various amounts in mucosal secretions as well as in the circulation. They have been linked to both inflammatory diseases and to various types of cancer, and serum concentrations of TFF3 show a more than 47-fold increase during pregnancy. Several both commercial and in-house immunoassays exist, but a number of methodological issues remain unresolved. This review describes methodological challenges in the measurement of the peptides in humans, and summarizes current knowledge concerning the occurrence and possible significance of the peptides in human health and disease.

Endometrial carcinoma: molecular alterations involved in tumor development and progression

In the western world, endometrial carcinoma (EC) is the most common cancer of the female genital tract. The annual incidence has been estimated at 10-20 per 100,000 women. Two clinicopathological variants are recognized: the estrogen related (type I, endometrioid) and the non-estrogen related (type II, non-endometrioid).The clinicopathological differences are paralleled by specific genetic alterations, with type I showing microsatellite instability and mutations in phosphatase and tensin homologue deleted on chromosome 10, PIK3CA, K-RAS and CTNNB1 (β-catenin), and type II exhibiting TP53 mutations and chromosomal instability. Some non-endometrioid carcinomas probably arise from pre-existing endometrioid carcinomas as a result of tumor progression and, not surprisingly, some tumors exhibit combined or mixed features at the clinical, pathological and molecular levels. In EC, apoptosis resistance may have a role in tumor progression. Understanding pathogenesis at the molecular level is essential in identifying biomarkers for successful targeted therapies. In this review, the genetic changes of endometrial carcinogenesis are discussed in the light of the morphological features of the tumors and their precursors.

Trop-2 overexpression in poorly differentiated endometrial endometrioid carcinoma: implications for immunotherapy with hRS7, a humanized anti-trop-2 monoclonal antibody

OBJECTIVE

We evaluated the expression of human trophoblast cell surface marker (Trop-2) in endometrial endometrioid carcinoma (EEC) and the potential application of hRS7, a humanized monoclonal anti-Trop-2 antibody, as a therapeutic agent against poorly differentiated EEC.

METHODS

Trop-2 expression was evaluated by immunohistochemistry in 131 EEC with different degrees of differentiation and 32 normal endometrial controls (NEC). Trop-2 expression was also evaluated by quantitative real-time polymerase chain reaction and flow cytometry in 3 primary EEC cell lines derived from patients harboring poorly differentiated EEC. Finally, the sensitivity of grade 3 EEC cell lines to hRS7 antibody-dependent cellular cytotoxicity was tested in standard 5-hour Cr release assays.

RESULTS

Trop-2 expression was detected in 126 (96.2%) of 131 EEC samples. Tumor tissues showed markedly increased Trop-2 positivity compared with NEC (P = 0.001). Trop-2 expression was significantly higher in all grades of EEC versus NEC. Grade 3 tumors displayed significantly stronger Trop-2 immunostaining compared with grade 1 EEC (P = 0.01). High Trop-2 expression by quantitative real-time polymerase chain reaction and flow cytometry was found in 1 grade 3 EEC primary cell line (EEC-ARK-1). Unlike Trop-2-negative EEC cell lines, EEC-ARK-1 was found highly sensitive to hRS7-mediated antibody-dependent cellular cytotoxicity in vitro (range of killing, 33.9%-50.6%; P = 0.004). Human serum did not significantly inhibit hRS7-mediated cytotoxicity against EEC-ARK-1 (P = 0.773).

CONCLUSIONS

Trop-2 is highly expressed in EEC, and its expression is significantly higher in poorly differentiated EEC when compared with well-differentiated EEC. Primary grade 3 EECs overexpressing Trop-2 are highly sensitive to hRS7-mediated cytotoxicity in vitro. hRS7 may represent a novel therapeutic agent for the treatment of high-grade EEC refractory to standard treatment modalities.

The combination of serum trefoil factor 3 and pepsinogen testing is a valid non-endoscopic biomarker for predicting the presence of gastric cancer: a new marker for gastric cancer risk

BACKGROUND

A valid biomarker for predicting the presence of gastric cancer may contribute to reducing deaths from this disease. Although pepsinogen (PG) testing has been introduced as a predictor, its predictive power is not satisfactory. We examined whether serum trefoil factor (TFF) could be a non-endoscopic predictor of the presence of gastric cancer.

METHODS

Gastric cancer patients who underwent preoperative endoscopy were sequentially recruited. Individuals who underwent a thorough medical checkup were enrolled as non-cancer controls. Serum levels of TFF1, TFF2, TFF3, Helicobacter pylori antibody, PG I, and PG II were examined.

RESULTS

We studied 192 gastric cancer patients aged 64.3 ± 9.7 years and 1254 non-cancer controls aged 52.3 ± 12.4 years. In the age/gender-matched analysis (187 cases and 561 controls), significant relationships were demonstrated between gastric cancer presence and TFF3 (P < 0.0001), the PGI/II ratio (P < 0.0001), H. pylori antibody (P = 0.001), TFF1 (P = 0.012), and TFF2 (P = 0.020). The area under the receiver-operating characteristic curve for predicting gastric cancer presence was comparably high for all factors (0.893) and for the combination of TFF3 and the PG test (0.883), but was significantly (P < 0.0001) lower for the PG test alone (0.823). A positive PG test showed a sensitivity of 67% and specificity of 82%, whereas a combination of TFF3 and PG testing showed a sensitivity of 80% and specificity of 80% in predicting the presence of gastric cancer.

CONCLUSION

The combination of serum TFF3 and PG testing might be a valid non-endoscopic biomarker for predicting the presence of gastric cancer.

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.

Microarray analysis reveals distinct gene expression profiles among different tumor histology, stage and disease outcomes in endometrial adenocarcinoma

BACKGROUND

Endometrial cancer is the most common gynecologic malignancy in developed countries and little is known about the underlying mechanism of stage and disease outcomes. The goal of this study was to identify differentially expressed genes (DEG) between late vs. early stage endometrioid adenocarcinoma (EAC) and uterine serous carcinoma (USC), as well as between disease outcomes in each of the two histological subtypes.

METHODOLOGY/PRINCIPAL FINDING

Gene expression profiles of 20 cancer samples were analyzed (EAC = 10, USC = 10) using the human genome wide illumina bead microarrays. There was little overlap in the DEG sets between late vs. early stages in EAC and USC, and there was an insignificant overlap in DEG sets between good and poor prognosis in EAC and USC. Remarkably, there was no overlap between the stage-derived DEGs and the prognosis-derived DEGs for each of the two histological subtypes. Further functional annotation of differentially expressed genes showed that the composition of enriched function terms were different among different DEG sets. Gene expression differences for selected genes of various stages and outcomes were confirmed by qRT-PCR with a high validation rate.

CONCLUSION

This data, although preliminary, suggests that there might be involvement of distinct groups of genes in tumor progression (late vs. early stage) in each of the EAC and USC. It also suggests that these genes are different from those involved in tumor outcome (good vs. poor prognosis). These involved genes, once clinically verified, may be important for predicting tumor progression and tumor outcome.

Microarray analysis reveals distinct gene expression profiles among different tumor histology, stage and disease outcomes in endometrial adenocarcinoma

Background

Endometrial cancer is the most common gynecologic malignancy in developed countries and little is known about the underlying mechanism of stage and disease outcomes. The goal of this study was to identify differentially expressed genes (DEG) between late vs. early stage endometrioid adenocarcinoma (EAC) and uterine serous carcinoma (USC), as well as between disease outcomes in each of the two histological subtypes.

Methodology/Principal Finding

Gene expression profiles of 20 cancer samples were analyzed (EAC = 10, USC = 10) using the human genome wide illumina bead microarrays. There was little overlap in the DEG sets between late vs. early stages in EAC and USC, and there was an insignificant overlap in DEG sets between good and poor prognosis in EAC and USC. Remarkably, there was no overlap between the stage-derived DEGs and the prognosis-derived DEGs for each of the two histological subtypes. Further functional annotation of differentially expressed genes showed that the composition of enriched function terms were different among different DEG sets. Gene expression differences for selected genes of various stages and outcomes were confirmed by qRT-PCR with a high validation rate.

Conclusion

This data, although preliminary, suggests that there might be involvement of distinct groups of genes in tumor progression (late vs. early stage) in each of the EAC and USC. It also suggests that these genes are different from those involved in tumor outcome (good vs. poor prognosis). These involved genes, once clinically verified, may be important for predicting tumor progression and tumor outcome.

Detection of elevated plasma levels of epidermal growth factor receptor before breast cancer diagnosis among hormone therapy users

Applying advanced proteomic technologies to prospectively collected specimens from large studies is one means of identifying preclinical changes in plasma proteins that are potentially relevant to the early detection of diseases such as breast cancer. We conducted 14 independent quantitative proteomics experiments comparing pooled plasma samples collected from 420 estrogen receptor-positive (ER(+)) breast cancer patients ≤17 months before their diagnosis and matched controls. Based on the more than 3.4 million tandem mass spectra collected in the discovery set, 503 proteins were quantified, of which 57 differentiated cases from controls with a P value of <0.1. Seven of these proteins, for which quantitative ELISA assays were available, were assessed in an independent validation set. Of these candidates, epidermal growth factor receptor (EGFR) was validated as a predictor of breast cancer risk in an independent set of preclinical plasma samples for women overall [odds ratio (OR), 1.44; P = 0.0008] and particularly for current users of estrogen plus progestin (E + P) menopausal hormone therapy (OR, 2.49; P = 0.0001). Among current E + P users, the EGFR sensitivity for breast cancer risk was 31% with 90% specificity. Whereas the sensitivity and specificity of EGFR are insufficient for a clinically useful early detection biomarker, this study suggests that proteins that are elevated preclinically in women who go on to develop breast cancer can be discovered and validated using current proteomic technologies. Further studies are warranted to examine the role of EGFR and to discover and validate other proteins that could potentially be used for early detection of breast cancer.

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.

Serum amyloid A: a novel biomarker for endometrial cancer

BACKGROUND

The authors investigated the expression of serum amyloid A (SAA) in endometrial endometrioid carcinoma and evaluated its potential as a serum biomarker.

METHODS

SAA gene and protein expression levels were evaluated in endometrial endometrioid carcinoma and normal endometrial tissues, by real-time polymerase chain reaction (PCR), immunohistochemistry (IHC), and flow cytometry. SAA concentration in 194 serum samples from 50 healthy women, 42 women with benign diseases, and 102 patients including 49 grade 1, 38 grade 2, and 15 grade 3 endometrial endometrioid carcinoma was also studied by a sensitive bead-based immunoassay.

RESULTS

SAA gene expression levels were significantly higher in endometrial endometrioid carcinoma when compared with normal endometrial tissues (mean copy number by real-time PCR = 182 vs 1.9; P = .001). IHC revealed diffuse cytoplasmic SAA protein staining in poorly differentiated endometrial endometrioid carcinoma tissues. High intracellular levels of SAA were identified in primary endometrial endometrioid carcinoma cell lines evaluated by flow cytometry, and SAA was found to be actively secreted in vitro. SAA concentrations (microg/mL) had medians of 6.0 in normal healthy women and 6.0 in patients with benign disease (P = .92). In contrast, SAA values in the serum of endometrial endometrioid carcinoma patients had a median of 23.7, significantly higher than those of the healthy group (P = .001) and benign group (P = .001). Patients harboring G3 endometrial endometrioid carcinoma were found to have SAA concentrations significantly higher than those of G1/G2 patients.

CONCLUSIONS

SAA is not only a liver-secreted protein, but is also an endometrial endometrioid carcinoma cell product. SAA is expressed and actively secreted by G3 endometrial endometrioid carcinoma, and it is present in high concentration in the serum of endometrial endometrioid carcinoma patients. SAA may represent a novel biomarker for endometrial endometrioid carcinoma to monitor disease recurrence and response to therapy.