Expression of epithelial to mesenchymal transition-related markers in lymph node metastases as a surrogate for primary tumor metastatic potential in breast cancer

Intertumoral Heterogeneity of Primary Breast Tumors and Synchronous Axillary Lymph Node Metastases Reflected in IHC-Assessed Expression of Routine and Nonstandard Biomarkers

Breast cancer (BC) remains a significant healthcare challenge. Routinely, the treatment strategy is determined by immunohistochemistry (IHC)-based assessment of the key proteins such as estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and Ki-67. However, it is estimated that over 75% of deaths result from metastatic tumors, indicating a need to develop more accurate protocols for intertumoral heterogeneity assessment and their consequences on prognosis. Therefore, the aim of this preliminary study was the identification of the expression profiles of routinely used biomarkers (ER, PR, HER2, Ki-67) and additional relevant proteins [Bcl-2, cyclin D1, E-cadherin, Snail+Slug, gross cystic disease fluid protein 15 (GCDFP-15), programmed death receptor 1 (PD-L1), and phosphatase of regenerating liver 3 (PRL-3)] in breast primary tumors (PTs) and paired synchronous axillary lymph node (ALN) metastases. A total of 67 tissue samples met the inclusion criteria for the study. The expression status of biomarkers was assessed in PTs and ALN metastases using tissue microarrays followed by IHC. In 11 cases, the shift of intrinsic molecular BC subtype was noticed between PTs and paired ALN metastases. Moreover, a significant disproportion in E-cadherin presence (p = 0.0002) was noted in both foci, and the expression status of all proteins except for HER2 demonstrated considerable variance (k = 1, p < 0.0001). Importantly, in around 30% of cases, the ALN metastases demonstrated discordance, i.e., loss/gain of expression, compared to the PTs. Intertumoral synchronous heterogeneity in both foci (primary tumor and node metastasis) is an essential phenomenon affecting the clinical subtype and characteristics of BC. Furthermore, a greater understanding of this event could potentially improve therapeutic efficacy.

The role of hypoxia in the tumor microenvironment and development of cancer stem cell: a novel approach to developing treatment

Hypoxia is a common feature of solid tumors, and develops because of the rapid growth of the tumor that outstrips the oxygen supply, and impaired blood flow due to the formation of abnormal blood vessels supplying the tumor. It has been reported that tumor hypoxia can: activate angiogenesis, thereby enhancing invasiveness and risk of metastasis; increase survival of tumor, as well as suppress anti-tumor immunity and hamper the therapeutic response. Hypoxia mediates these effects by several potential mechanisms: altering gene expression, the activation of oncogenes, inactivation of suppressor genes, reducing genomic stability and clonal selection. We have reviewed the effects of hypoxia on tumor biology and the possible strategiesto manage the hypoxic tumor microenvironment (TME), highlighting the potential use of cancer stem cells in tumor treatment.

Expression of epithelial-mesenchymal transition-related markers and phenotypes during breast cancer progression

Purpose

The study aimed to investigate expression of epithelial-to-mesenchymal transition (EMT)-related proteins and phenotypes during breast cancer progression and to relate this to patient outcome.

Methods

Protein expression patterns of E-cadherin, N-cadherin, twist, and vimentin were examined by immunohistochemistry on formalin-fixed paraffin-embedded samples from primary tumors (PTs) (n = 419), synchronous lymph node metastases (LNMs) (n = 131) and recurrences (n = 34) from patients included in an observational prospective primary breast cancer study. Markers were evaluated individually and combined as defined EMT phenotypes (epithelial, mesenchymal, partial EMT, and negative). EMT profiles were compared between matched tumor progression stages, and related to clinicopathological data and distant recurrence-free interval (DRFi).

Results

N-cadherin-positivity, vimentin-positivity, mesenchymal and partial EMT phenotypes were associated with more aggressive tumor characteristics such as triple-negative subtype. Single EMT markers and phenotype discordance rates between paired tumor samples were observed in the range of 2–35%. Non-epithelial phenotypes were more frequently identified in recurrences compared to PTs, however, no skewness of expression or phenotype was detected between PTs and matched LNMs or between PTs and matched recurrences (Exact McNemar test). Interestingly, patients with a twist positive PT had shorter DRFi, compared to patients with a twist negative PT (hazard ratio (HR) 2.4, 95% confidence interval (CI) 1.2–5.1, P = 0.02). Essentially, the same effect was seen in multivariable analysis (HR 2.5, 95% CI 0.97–6.6, P = 0.06).

Conclusion

The epithelial phenotype was indicated to be lost between PTs and recurrences as a reflection of tumor progression. Twist status of the PT was related to long-term prognosis warranting further investigation in larger cohorts.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05627-0) contains supplementary material, which is available to authorized users.

Profiling of Invasive Breast Carcinoma Circulating Tumour Cells-Are We Ready for the 'Liquid' Revolution?

As dissemination through blood and lymph is the critical step of the metastatic cascade, circulating tumour cells (CTCs) have attracted wide attention as a potential surrogate marker to monitor progression into metastatic disease and response to therapy. In patients with invasive breast carcinoma (IBC), CTCs are being considered nowadays as a valid counterpart for the assessment of known prognostic and predictive factors. Molecular characterization of CTCs using protein detection, genomic and transcriptomic panels allows to depict IBC biology. Such molecular profiling of circulating cells with increased metastatic abilities appears to be essential, especially after tumour resection, as well as in advanced disseminated disease, when information crucial for identification of therapeutic targets becomes unobtainable from the primary site. If CTCs are truly representative of primary tumours and metastases, characterization of the molecular profile of this easily accessible ‘biopsy’ might be of prime importance for clinical practice in IBC patients. This review summarizes available data on feasibility and documented benefits of monitoring of essential IBC biological features in CTCs, with special reference to multifactorial proteomic, genomic, and transcriptomic panels of known prognostic or predictive value.

Limited utility of tissue micro-arrays in detecting intra-tumoral heterogeneity in stem cell characteristics and tumor progression markers in breast cancer

Background

Intra-tumoral heterogeneity has been recently addressed in different types of cancer, including breast cancer. A concept describing the origin of intra-tumoral heterogeneity is the cancer stem-cell hypothesis, proposing the existence of cancer stem cells that can self-renew limitlessly and therefore lead to tumor progression. Clonal evolution in accumulated single cell genomic alterations is a further possible explanation in carcinogenesis. In this study, we addressed the question whether intra-tumoral heterogeneity can be reliably detected in tissue-micro-arrays in breast cancer by comparing expression levels of conventional predictive/prognostic tumor markers, tumor progression markers and stem cell markers between central and peripheral tumor areas.

Methods

We analyzed immunohistochemical expression and/or gene amplification status of conventional prognostic tumor markers (ER, PR, HER2, CK5/6), tumor progression markers (PTEN, PIK3CA, p53, Ki-67) and stem cell markers (mTOR, SOX2, SOX9, SOX10, SLUG, CD44, CD24, TWIST) in 372 tissue-micro-array samples from 72 breast cancer patients. Expression levels were compared between central and peripheral tumor tissue areas and were correlated to histopathological grading. 15 selected cases additionally underwent RNA sequencing for transcriptome analysis.

Results

No significant difference in any of the analyzed between central and peripheral tumor areas was seen with any of the analyzed methods/or results that showed difference. Except mTOR, PIK3CA and SOX9 (nuclear) protein expression, all markers correlated significantly (p < 0.05) with histopathological grading both in central and peripheral areas.

Conclusion

Our results suggest that intra-tumoral heterogeneity of stem-cell and tumor-progression markers cannot be reliably addressed in tissue-micro-array samples in breast cancer. However, most markers correlated strongly with histopathological grading confirming prognostic information as expression profiles were independent on the site of the biopsy was taken.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1495-6) contains supplementary material, which is available to authorized users.

Aggressive Phenotype of Cells Disseminated via Hematogenous and Lymphatic Route in Breast Cancer Patients

Intratumoral heterogeneity of breast cancer remains a major challenge in successful treatment. Failure of cancer therapies can also be accredited to inability to systemically eradicate cancer stem cells (CSCs). Recent evidence points to the role of epithelial-mesenchymal transition (EMT) in expanding the pool of tumor cells with CSCs features. Thus, we assessed expression level as well as heterogeneity of CSCs markers in primary tumors (PT), lymph node metastasis (LNM), and circulating tumor cells (CTCs)-enriched blood fractions in order to correlate them with signs of EMT activation as well as clinicopathological data of breast cancer patients. Level of CSCs markers (ALDH1, CD44, CD133, OCT-4, NANOG) and EMT markers was quantified in PT (N=107), LNM (N=56), and CTCs-enriched blood fractions (N=85). Heterogeneity of CSCs markers expression within each PT and LNM was assessed by calculating Gini Index. Percentage of ALDH1-positive cells was elevated in PT in comparison to LNM (P = .005). However, heterogeneity of the four CSCs markers: ALDH1 (P = .019), CD133 (P = .009), OCT-4 (P = .027), and CD44 (P < .001) was decreased in LNM. Samples classified as mesenchymal (post-EMT) showed elevated expression of CSCs markers (OCT-4 and CD44 in PT; OCT-4 in LNM; ALDH1, OCT-4, NANOG, CD44 in CTCs). Patients with mesenchymal-like CTCs had worse prognosis than patients with epithelial-like or no CTCs (P = .0025). CSCs markers are enriched in PT, LNM, and CTCs with mesenchymal features, but their heterogeneity is decreased in metastatic lymph nodes. Mesenchymal CTCs phenotype correlates with poor prognosis of the patients.

Overexpression of Lox in triple-negative breast cancer

BACKGROUND

Triple negative breast cancer (TNBC) accounts for approximately 15% of breast cancers. It is associated with a poor prognosis and typically earlier onset of metastasis in comparison with other breast cancer subtypes. Since TNBC lacks the expression of estrogen and progesterone receptors and Her2 status is also negative, there is currently no target that can be used for systemic therapy. Epithelial-mesenchymal transition (EMT) plays an important role in tumor progression and metastasis. In this study, we examined a subset of EMT markers consisting of Snail, Twist-1 and Lox in TNBC and non-TNBC breast cancer subtypes and analyzed their expression pattern in regard to subtype, clinico-pathological parameters and prognosis.

EXPERIMENTAL DESIGN

We analyzed 659 breast cancer samples from two tissue microarrays. Breast cancer samples were categorized into two groups according to hormone receptor expression and Her2 status (n = 146 were triple negative, n = 513 were non triple-negative). Immunohistochemical expression of Snail, Twist-1 and Lox was semi-quantitatively analyzed using a three-tiered (weak-moderate-strong) scoring system. Results were statistically analyzed and correlated to clinico-pathological parameters and overall survival.

RESULTS

Strong overexpression of Lox was significantly higher in triple negative breast cancers when compared to non triple-negative breast cancers (p < 0.001). No difference was seen between the groups regarding Snail and Twist expression (p > 0.05). In addition, Lox expression was significantly stronger in poorly differentiated (G3) breast cancers (p < 0.001 for Lox).

CONCLUSIONS

The EMT marker Lox has a differential expression pattern in breast cancer, being significantly overexpressed in triple negative breast cancers. We could not link this expression to prognosis, however, this marker might be explored in future studies as possible target for systemic therapy of TNBC.

Heterogeneity of PD-L1 expression in primary tumors and paired lymph node metastases of triple negative breast cancer

Background

Programmed cell death ligand 1 (PD-L1) is a potential predictive biomarker of the response to anti-PD-L1/anti- programmed cell death 1 (PD-1) therapy in multiple cancers, including triple negative breast cancer(TNBC). The purpose of this study was to investigate whether PD-L1 expression is homogenous in primary tumors(PTs) and synchronous axillary lymph node metastases(LNMs) of TNBC.

Methods

PD-L1 expression was immunohistochemically evaluated in 101 TNBC patients’ PTs and paired LNMs. PD-L1 expression in tumor cells and infiltrating immune cells or node lymphocytes in the PTs and associated LNMs was scored separately and was correlated with patients’ clinical parameters and prognoses.

Results

PD-L1 expression exhibited spatial heterogeneity in both the tumor cells and the infiltrating immune cells or node lymphocytes of PTs and LNMs. The PD-L1 expression levels were significantly higher in the lymphocytes and tumor cells of the LNMs than in the PTs. PD-L1 expression was also more frequent among the LNMs. PD-L1 expression was associated with high grade and more stromal tumor-infiltrating lymphocytes(TILs). Furthermore, the disease-free survival and overall survival were similar between the PT- negative/LNM- positive and PT- positive/LNM- positive patients, both of which exhibited worse disease-free survival(DFS) thanPT -negative/LNM -negative patients.

Conclusions

The differential expression of PD-L1 between the PTs and LNMs suggests that LNMs PD-L1 status may be used to indicate whether PD-1/PD-L1-targeted therapy would be suitable for a node-positive TNBC patient in the future.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3916-y) contains supplementary material, which is available to authorized users.

Prognostic significance of expression of epithelial-mesenchymal transition driver brachyury in breast cancer and its association with subtype and characteristics

Brachyury is a T-box transcription factor characterized as a driver of the epithelial-to-mesenchymal process, which is associated with poor prognosis of patients with breast cancer. The present study investigated expression of brachyury in breast cancer including primary tumor, metastatic and recurred tumor tissues, and the clinical significance and value of brachyury as a prognostic biomarker. This retrospective study included a series of 102 consecutive patients surgically resected between January 2005 and December 2011. Brachyury expression in tumor cell was evaluated using immunohistochemistry and scored as the immunoactivity. Of 102 patients, 62 primary tumors were positive for brachyury expression and 40 were negative. Multivariate analysis of disease-free survival (DFS) revealed brachyury expression, HER2 and lymphovascular invasion as independent prognostic factors [brachyury negative vs. positive hazard ratio (HR), 3.0; P=0.024; HER2 negative vs. positive HR, 4.9; P=0.003; lymphovascular invasion absent vs. present HR, 3.5; P=0.020]. These results were particularly observed in triple-negative breast cancer (TNBC), no recurrence or mortality occurred in brachyury negative group during the follow-up period, and therefore a significantly improved prognosis was demonstrated in these patients compared with the brachyury positive group [overall survival (OS), P=0.022; DFS, P=0.002]. Brachyury expression in metastatic lymph node/recurred tumors was not significantly associated with prognosis (OS, P=0.745; DFS, P=0.189). Therefore, Brachyury expression in primary tumor independently is a potential predictor of poor prognosis, particularly in TNBC, where it appears to serve a crucial function in recurrence and mortality. Brachyury vaccines under clinical trials are likely to be useful in patients with breast cancer.

Prognostic and clinicopathological value of Twist expression in breast cancer: A meta-analysis

Background

Despite initial indications that the transcription factor Twist could be used as a breast cancer prognostic marker, there still exists some controversy about its reliability. Thus, the aim of the present study was to assess the relationship between Twist expression and prognosis in breast carcinoma.

Materials and methods

We identified eligible studies that reported an association between Twist expression and breast cancer prognosis by searching the literature in PubMed, Embase, the Cochrane Library, and Web of Science databases, through June 5, 2017. Studies investigating Twist protein or mRNA expression as well as reporting survival data in breast cancer were included. The pooled hazard ratio (HR) and odds radio (OR) with a 95% confidence interval (95% CI) were used to estimate associations.

Results

A total of 2,671 patients from seven included studies were assessed, and the data indicated that increased Twist expression significantly correlated with poor overall survival (OS) (HR, 1.15; 95% CI, 1.00–1.33; P = 0.04) in breast cancer. In addition, we also observed a significant correlation of elevated Twist expression with larger tumor size (OR, 1.92; 95% CI, 1.31–2.81; P = 0.0009), lymph node involvement (OR, 3.81; 95% CI, 1.16–12.54; P = 0.03), higher nuclear grade (OR, 1.45; 95% CI, 1.06–2.00; P = 0.02), and positive human epidermal growth factor receptor 2 (HER2) status (OR, 1.49; 95% CI, 1.06–2.09; P = 0.02). However, no correlation between Twist expression and disease-free survival (DFS), age, estrogen receptor (ER) status, and progesterone receptor (PR) status was observed.

Conclusions

Our results demonstrate that Twist over-expression is a statistically significant indicator of OS in breast cancer. In addition, our meta-analysis shows that increased Twist expression is significantly associated with larger tumor size, lymph node involvement, higher nuclear grade, and positive HER2 status.

Clinical significance of altering epithelial-mesenchymal transition in metastatic lymph nodes of gastric cancer

BACKGROUND

The E-cadherin, N-cadherin, and Snail genes are epithelial-mesenchymal transition (EMT)-inducible genes. Previous studies demonstrated that the expression of EMT markers in the primary tumor sites of gastric cancer correlates with tumor progression and prognosis. However, the clinical significance of the expression of these EMT markers in metastatic lymph nodes remains unclear. In the present study, we investigated the expression of these EMT markers in the primary tumor sites and metastatic lymph nodes.

METHODS

Immunohistochemistry was used to investigate the expression of E-cadherin, N-cadherin, and Snail in 89 primary tumors and 511 metastatic lymph nodes obtained from patients with gastric cancer.

RESULTS

The weak expression of E-cadherin in tumors and lymph nodes increased with more lymph node metastasis and in more undifferentiated tumors. The strong expression of N-cadherin in lymph nodes correlated with more lymph nodes metastasis, an advanced stage, and poor prognosis. The weak expression of Snail in tumors correlated with lymphatic invasion. The strong expression of Snail in lymph nodes correlated with more lymph node metastasis and an advanced stage. The strong expression of Snail in tumors and its weak expression in lymph nodes correlated with more lymph node metastasis, an advanced stage, and poor prognosis.

CONCLUSIONS

The expression of N-cadherin in metastatic lymph nodes is useful for predicting the prognosis of patients with gastric cancer. The Snail switch-namely, the positive-to-negative conversion of the Snail status-between primary tumors and lymph node metastasis may be important for confirming EMT and mesenchymal-epithelial transition.

Overexpression of EMT-inducing transcription factors as a potential poor prognostic factor for hepatocellular carcinoma in Asian populations: A meta-analysis

Background and Objectives

The clinical relevance of epithelial to mesenchymal transition (EMT) in hepatocellular carcinoma (HCC) progression has been highlighted during the last decade. The zinc finger E-box binding homeobox (ZEB) family, the zinc-finger transcriptional repressor (SNAI) family, and the basic helix-loop-helix transcription factor (Twist) family, known as the prominent EMT-inducing transcription factors (EMT-TFs), played a crucial role in the process of EMT. Here, this meta-analysis aimed to evaluate the prognostic value of EMT-TFs high expression in patients with HCC after hepatectomy.

Results

A total of 10 studies involving 1334 patients were retrieved for analysis, the synthetic date indicated that EMT-TFs overexpression was associated with poor postoperative overall survival (OS) [HR = 1.71; 95% CI: 1.40–2.08; p < 0.00001] in HCC. The subgroup analyses revealed that overexpression of each individual EMT-TF (in addition to ZEB2) tended to be associated with poor OS. Moreover, EMT-TFs overexpression correlated with TNM stage, poor histological differentiation, intrahepatic metastasis and vascular invasion.

Materials and Methods

Relevant literature search in the PubMed, Web of Science database and Cochrane Library was performed to retrieve all eligible studies. The pooled hazard ratio (HR) or odds ratio (OR) with its 95% confidence interval (CI) were calculated to investigation clinicopathological and prognostic significance of EMT-TFs expression in HCC.

Conclusions

EMT-TFs overexpression indicated an unfavorable prognosis in HCC patients following curative resection.

Combination Twist1 and CA15-3 in axillary lymph nodes for breast cancer prognosis

Twist1 overexpression is involved in epithelial-mesenchymal transition resulting in migration and metastasis of breast cancer. Carcinoma antigen 15–3 (CA15-3) is widely used to monitor the prognosis for patients after treatment. However, the significance of Twist1 in axillary lymph nodes (ALN) and CA15-3 for co-examination for survival rates remains to be elucidated. The present study aimed to explore the role of the combination of Twist1 expression in metastasized ALN and the serum level of CA15-3 in evaluating the prognosis of patients with breast cancer. cluster of differentiation (CD)44, CD24, aldehyde dehydrogenase (ALDH)1 and Twist1 expression in normal and metastasized ALN from 102 patients with breast cancer were detected using laser confocal microscopy and the expression of the genes evaluated by reverse transcription-quantitative polymerase chain reaction; E-cadherin, N-cadherin and vimentin expression was also tested by western blotting. The serum concentrations of CA15-3 prior to and following surgery were analyzed by chemiluminescence immunoassay. The expression of CD44, ALDH1 and Twist1 mRNA in the primary breast cancer tissues and involved ALN was upregulated compared with the normal ALN (P<0.05). The proteins N-cadherin and vimentin of the involved ALN were poorly expressed compared with breast cancer tissues, however E-cadherin protein expression was higher in metastasized and normal ALN compared with primary cancer tissues (P<0.05). Of the 102 patients, the serum CA15-3 levels of the patients in stages I and II were significantly lower compared with stages III and IV (P<0.05). Twist1⁺/CA15-3⁺, HER2-negative/Twist1⁺/CA15-3⁺ and Triple-receptor negative/Twist1⁺/CA15-3⁺ groups displayed a shorter progression-free survival compared with others. The results of the present study demonstrated that CD44, ALDH1 and Twist1 were significantly overexpressed in involved ALN. The serum levels of CA15-3 in those patients were clearly increased and the survival rates decreased, which suggested that a combination of Twist1 in ALN and CA15-3 may function as an indicator for the prognosis of patients with breast cancer.

Roles and epigenetic regulation of epithelial-mesenchymal transition and its transcription factors in cancer initiation and progression

The epithelial-mesenchymal transition (EMT) is a crucial developmental process by which epithelial cells undergo a mesenchymal phenotypic change. During EMT, epigenetic mechanisms including DNA methylation and histone modifications are involved in the regulation of EMT-related genes. The epigenetic gene silencing of the epithelial marker E-cadherin has been well characterized. In particular, three major transcriptional repressors of E-cadherin, Snail, ZEB, and Twist families, also known as EMT-inducing transcription factors (EMT-TFs), play a crucial role in this process by cooperating with multiple epigenetic modifiers. Furthermore, recent studies have identified the novel epigenetic modifiers that control the expression of EMT-TFs, and these modifiers have emerged as critical regulators of cancer development and as novel therapeutic targets for human cancer. In this review, the diverse functions of EMT-TFs in cancer progression, the cooperative mechanisms of EMT-TFs with epigenetic modifiers, and epigenetic regulatory roles for the expression of EMT-TFs will be discussed.

Prognostic Significance of Expression of the Epithelial-Mesenchymal Transition-Related Factor Brachyury in Intrathoracic Lymphatic Spread of Non-Small Cell Lung Cancer

BACKGROUND

Brachyury is a transcriptional regulator that plays important roles in epithelial mesenchymal transition (EMT) during development and has been reported to be essential for mesoderm formation in the early human embryo. We investigated Brachyury protein expression in hilar and mediastinal metastatic lymph nodes of non-small cell lung cancer patients and the prognostic significance of Brachyury expression at metastatic sites.

METHODS

Expression of Brachyury in 115 surgically resected primary lung cancer and corresponding metastatic lymph node samples was evaluated by immunohistochemical staining. The relationships between Brachyury protein expression and the patient's clinicopathological factors and prognosis were analyzed.

RESULTS

Brachyury expression in metastatic lymph nodes was significantly higher than that in the primary tumor (p = 0.012). Patients with high Brachyury expression in the metastatic lymph nodes had significantly poor prognoses (p = 0.0236) compared with patients with low expression. In addition, patients with larger differences in Brachyury expression between metastatic lymph nodes and the primary tumor had significantly poorer prognoses compared with patients with smaller differences (p = 0.0146). The Brachyury protein expression level in metastatic lymph nodes was significantly associated with the protein expression levels of other EMT-related factors (E-cadherin [inverse association], p = 0.0265; Slug, p = 0.029; and interleukin-8, p = 0.0135).

CONCLUSIONS

High expression of Brachyury protein in metastatic carcinoma cells in the intrathoracic lymph nodes was associated with poor prognosis of lung cancer patients. Increased Brachyury expression during the metastatic process may confer further potential for invasion and metastasis of cancer cells.

Stromal expression of ALDH1 in human breast carcinomas indicates reduced tumor progression

Interactions between cancer cells and microenvironment are emerging issue in tumor progression. Aldehyde dehydrogenase 1 (ALDH1) is a recognized cancer stem cell marker but little is known about its role in intratumoral stroma. Therefore, we focused on ALDH1 expression in tumor-associated stroma of breast carcinomas (BrCa).

Stromal and tumoral ALDH1 expression was evaluated immunohistochemically in BrCa and their lymph node metastases (LNMs), and related to clinico-pathological characteristics, patients’ outcome, presence of CD68, HLADR, retinoic acid (RA) in stroma, and selected proteins in tumor cells.

ALDH1(+) stromal cells were detected in 53% of 374 BrCa and 61% of 102 LNMs. ALDH1(+) stroma in primary tumor correlated to longer disease-free (p = 0.030), metastasis-free (p = 0.024), and overall survival (p = 0.043) having an independent prognostic impact on DFS (multivariate analysis, p = 0.047). It was associated with concomitant presence of HLA-DR(+) stromal cells and RA in tumor cells (both p < 0.001), and inversely associated with vimentin expression in tumor cells (p = 0.036). ALDH1(+) stroma in LNMs correlated inversely to presence of disseminated tumor cells in patients’ bone marrow (p = 0.014) and was independent prognosticator of shorter DFS and MFS (multivariate analysis, p = 0.004 and p = 0.002, respectively).

In conclusion, ALDH1 expression in tumor-associated stromal cells indicates reduced BrCa progression, possibly via RA secretion.

Differential expression of epithelial–mesenchymal transition and stem cell markers in intrinsic subtypes of breast cancer

The transcription factors SLUG and SOX9 have been shown to define mammary stem cell state. Similarly, epithelial–mesenchymal transition (EMT) markers (E-Cadherin, mTOR) have been shown to play a role in tumor-progression and metastatic potential in breast cancer. Finally, SOX10 is known to be expressed in breast cancer as well. The overexpressions of EMT and stem cell markers have been shown to correlate with poor overall survival. In this study, we examined whether the expression of these markers correlates with intrinsic subtypes of breast cancer and whether there is a prognostic difference in their expression-profile. We analyzed 617 breast cancer samples from two tissue micro arrays. Breast cancer samples were categorized into three groups according to hormone receptor expression and HER2-status as Luminal A/B, HER2-positive, and triple negative subgroup. Immunohistochemical expressions of SLUG, SOX9, SOX10, E-Cadherin, and mTOR were semi-quantitatively analyzed using a two-tiered and three-tiered scoring system in which cytoplasmic and nuclear stains were considered. Strong nuclear expression of SLUG was observed preferentially in triple negative but not in Luminal A/B or HER2-positive cases (24 vs. 3 and 0 %, p < 0.001). Loss of SOX9 in the nuclear stain was less frequent in triple negative than in Luminal A/B or HER2-positive cases (4 vs. 9 vs. 13 %, p < 0.001). Expression of nuclear SOX10 was lower in triple negative than in Luminal A/B and HER2-positive cases (67 vs.78 and 79 %, p = 0.012). E-Cadherin loss was observed only in Luminal A/B tumors (p = 0.016), no difference in the mTOR expression was seen between any of the three groups. No correlation to conventional histopathological-parameters or stage could be established in our cohort. Our study shows an inversed preferential nuclear expression of SLUG, SOX10, and SOX9 in triple negative and non-triple negative cases. This information is important in understanding the biology of triple negative breast cancer, also in terms of future studies dealing with targeted therapies based on the alterations of EMT and stem cell markers.

The network of pluripotency, epithelial-mesenchymal transition, and prognosis of breast cancer

Breast cancer is the leading female cancer in terms of prevalence. Progress in molecular biology has brought forward a better understanding of its pathogenesis that has led to better prognostication and treatment. Subtypes of breast cancer have been identified at the genomic level and guide therapeutic decisions based on their biology and the expected benefit from various interventions. Despite this progress, a significant percentage of patients die from their disease and further improvements are needed. The cancer stem cell theory and the epithelial-mesenchymal transition are two comparatively novel concepts that have been introduced in the area of cancer research and are actively investigated. Both processes have their physiologic roots in normal development and common mediators have begun to surface. This review discusses the associations of these networks as a prognostic framework in breast cancer.

ZEB1 promotes the progression and metastasis of cervical squamous cell carcinoma via the promotion of epithelial-mesenchymal transition

OBJECTIVE

The process of epithelial-mesenchymal transition (EMT) clearly contributes to cancer metastasis. The aim of this study was to investigate the expression of the EMT-related transcription repressor ZEB1 and the expression of EMT-associated markers (E-cadherin, β-catenin and N-cadherin) in cervical squamous cell carcinoma. In addition, the role of ZEB1 and these EMT-associated markers in the progression and metastasis of cervical squamous cell carcinoma was explored.

METHODS

The expression of ZEB1, E-cadherin, β-catenin and N-cadherin was evaluated in 81 specimens of cervical squamous cell carcinoma by immunohistochemistry; the clinicopathological significance of these markers was then analyzed.

RESULTS

1) Of the 81 samples, 37 cases (45.7%) were positive for ZEB1, and nuclear expression of ZEB1 in tumor cells was positively associated with the differentiation status of the tumor tissue (P < 0.05), vascular invasion (P < 0.05) and lymph node metastasis (P < 0.05). 2) The loss of E-cadherin and β-catenin expression in tumor cells and the acquisition of N-cadherin expression were positively associated with the differentiation status of the tumor tissue (P < 0.05) and with the occurrence of vascular invasion (P < 0.05). 3) A significant negative correlation was observed between ZEB1 and E-cadherin expression (Spearman = -0.636, P < 0.05) and between ZEB1 and β-catenin expression (Spearman = -0.417, P < 0.05). Moreover, a significant positive correlation was observed between ZEB1 and N-cadherin expression (Spearman = 0.557, P < 0.05).

CONCLUSIONS

These results emphasize the role of EMT in cervical squamous cell carcinoma. The upregulation of ZEB1 is associated with the abnormal expression of E-cadherin, β-catenin and N-cadherin, which might promote the progression and metastasis of cervical squamous cell carcinoma.

Clinicopathological significance of KAI1 expression and epithelial-mesenchymal transition in non-small cell lung cancer

Background

KAI1 and epithelial-mesenchymal transition (EMT) is related to both angiogenesis and lymphangiogenesis and is an important target in new cancer treatment strategies. We aimed to investigate the KAI1 and marker of EMT expression and correlation with lymph node metastasis (LNM) and explore their prognostic impact in non-small cell lung cancer (NSCLC).

Methods

Tumor tissue specimens from 312 resected patients with stage I–IIIA NSCLC were obtained. Immunohistochemistry was used to assess the expression of the molecular markers KAI1, E-cadherin (E-cad), vimentin, CD34, and D2-40.

Results

There were 153 N0 and 159 N+ patients. Tumor cell expression of KAI1and the marker of EMT, lymphatic vessel density (LVD), and microvessel density (MVD) were related to LNM. In multivariate analyses, the ages of patients, high tumor cell KAI1 expression, EMT, and the scores of MVD were independent factor of prognosis.

Conclusions

Tumor cell KAI1 expression, EMT, LVD, and MVD correlate with LNM. Thus, the detection of KAI1, expression of markers of EMT, and the scores of MVD may be used as a potential indicator of NSCLC prognosis.

Drastic morphological and molecular differences between lymph node micrometastatic tumors and macrometastatic tumors of lung adenocarcinoma

PURPOSE

The expansion of micrometastatic tumors to macrometastatic ones is thought to be tightly regulated by several microenvironmental factors. The aim of this study was to elucidate the morphological and phenotypical differences between micrometastatic and macrometastatic tumors.

METHOD

We first examined the morphological characteristics of 66 lymph node (LN) micrometastatic tumors (less than 2 mm in size) and 51 macrometastatic tumors (more than 10 mm in size) in 42 lung adenocarcinoma cases. Then, we evaluated the expression level of E-cadherin, S100A4, ALDH1, and Geminin in cancer cells and the number of smooth muscle actin (SMA), CD34, and CD204 (+) stromal cells in the primary tumors, matched micrometastatic tumors, and macrometastatic tumors (n = 34, each).

RESULTS

Tumor budding reflects the process of EMT, and stromal reactions were observed more frequently in macrometastatic tumors (P < 0.001). E-cadherin staining score for the micrometastatic tumors was significantly higher than that for the primary tumors (P < 0.001). In contrast, the E-cadherin staining score for the macrometastatic tumors was significantly lower than that for the micrometastatic tumors (P = 0.017). As for the stromal cells, the numbers of SMA (+) fibroblasts, CD34 (+) microvessels, and CD204 (+) macrophages were significantly higher for the macrometastatic tumors and primary tumors than for the micrometastatic tumors (P < 0.001, all).

CONCLUSION

The present study clearly showed that dynamic microenvironmental changes (e.g., EMT-related changes in cancer cells and structural changes in stromal cells) occur during the growth of micrometastases into macrometastases.

In stage II/III lymph node-positive breast cancer patients less than 55 years of age, keratin 8 expression in lymph node metastases but not in the primary tumour is an indicator of better survival

Axillary lymph node status is one of the most important prognostic variables for breast cancer (BC). To investigate and understand the clinical, histopathological and biological factors that affect prognosis in node-positive young breast cancer patients, we compared the phenotype of 100 primary tumours with their corresponding loco-regional lymph node (LN) metastases using conventional immunohistochemistry (IHC) markers currently in use for molecular classification of breast cancer. By comparing the expression of ER, PR, HER-2, Ki67, K8, K5/6 and vimentin, we found that expression of HER-2, Ki67, K8 and vimentin is frequently lost in lymph node metastases. Between the primary tumour and corresponding lymph node metastases, expression of keratins K8 and K5/6 significantly changed. Expression of K8 in lymph node metastases, but not in primary tumours, segregates patients in two sub-groups with different outcomes. Survival of patients with K8-positive LN metastases at 5 years in comparison with patients with K8-negative LN metastases was 75 vs 48 %, at 10 years 62 vs 22 % and at 20 years 53 vs 14 % (p < 0.001). K8 immunostaining of tissue from the lymph node metastasis allows defining a sub-group of lymph node-positive BC patients with a highly unfavourable outcome, for whom therapeutic options might have to be reconsidered.

P-Cadherin Linking Breast Cancer Stem Cells and Invasion: A Promising Marker to Identify an "Intermediate/Metastable" EMT State

Epithelial–mesenchymal transition (also known as EMT) is a fundamental mechanism occurring during embryonic development and tissue differentiation, being also crucial for cancer progression. Actually, the EMT program contributes to the dissemination of cancer cells from solid tumors and to the formation of micro-metastasis that subsequently develop into clinically detectable metastases. Besides being a process that is defined by the progressive loss of epithelial cell characteristics and the acquisition of mesenchymal features, EMT has also been implicated in therapy resistance, immune escape, and maintenance of cancer stem cell properties, such as self-renewal capacity. However, the majority of the studies usually neglect the progressive alterations occurring during intermediate EMT states, which imply a range of phenotypic cellular heterogeneity that can potentially generate more metastable and plastic tumor cells. In fact, few studies have tried to identify these transitory states, partly due to the current lack of a detailed understanding of EMT, as well as of reliable readouts for its progression. Herein, a brief review of evidences is presented, showing that P-cadherin expression, which has been already identified as a breast cancer stem cell marker and invasive promoter, is probably able to identify an intermediate EMT state associated with a metastable phenotype. This hypothesis is based on our own work, as well as on the results described by others, which suggest the use of P-cadherin as a promising EMT marker, clearly functioning as an important clinical prognostic factor and putative therapeutic target in breast carcinogenesis.

Prognostic significance of the epithelial-to-mesenchymal transition markers e-cadherin, vimentin and twist in bladder cancer

OBJECTIVE

The goal of this study was to utilize long-term patient follow-up to determine whether epithelial-to-mesenchymal transition (EMT)-related markers can predict bladder cancer patient survival and progression of disease.

MATERIALS AND METHODS

This study included 121 patients with bladder cancer. Sixty-four of these patients presented with non-muscle invasive (NMI, stage T1) bladder cancer and 57 with muscle invasive (MI, stage T2, T3). The patients were diagnosed and treated between May 1998 and July 2012. The EMT markers E-cadherin, Twist, and Vimentin were detected via immunohistochemistry. Univariate and multivariate/Cox analyses were then utilized to determine whether these EMT markers could be useful prognostic markers for predicting bladder cancer patient outcomes.

RESULTS

Analysis of the 121 bladder cancer patients in this study revealed that the frequency of E-cadherin expression was 59.5% (72/121), Twist was 54.5% (66/121), and Vimentin was 24.8% (30/121). Twist and Vimentin were found to have statistically significant correlations with grade, recurrence, and progression but not with stage, whereas E-cadherin was associated with stage but not with the other parameters. In the univariate analysis, grade (p = 0.02) was the only significant predictor for progression-free survival (PFS). Stage, grade, and expression of E-cadherin, Vimentin and Twist were included in the multivariate analysis of predicting PFS. In this analysis, grade (p = 0.01) and Vimentin expression (p = 0.001) were found to be significant prognostic factors in predicting PFS.

CONCLUSIONS

Grade and Vimentin are potential independent indicators in predicting bladder cancer progression and survival.

Implications of the Notch1-Snail/Slug-epithelial to mesenchymal transition axis for lymph node metastasis in infiltrating ductal carcinoma

Emerging evidence suggests that activation of the Notch1 signaling pathway inducing epithelial to mesenchymal transition (EMT) mediated by Snail/Slug promotes invasion and metastasis of breast cancer cells in vitro. However, the implication of the Notch1-Snail/Slug-EMT axis in breast cancer patients remains unclear. A total of 200 formalin-fixed paraffin-embedded samples of invasive ductal carcinoma (IDC), and 37 adjacent non-neoplastic tissue (ANNT) samples from patients who had not been treated with neoadjuvant therapy were examined. Expression of Notch1, Slug, Snail, E-cadherin, N-cadherin, and vimentin was determined by immunohistochemistry on tissue microarrays (TMAs). The correlation between protein expression and clinicopathological characteristics of breast cancer patients was also evaluated. Results showed that a significantly high percentage of cases with high expression of Notch1 (74%, 148/200), Slug (36%, 72/200), Snail (62%, 124/200), and N-cadherin (77%, 153/200) and a low percentage of cases with high expression of E-cadherin (27%, 54/200) were observed in IDC compared to those in ANNTs. High Notch1, Slug, Snail, and N-cadherin expression and low E-cadherin expression in patients with IDC were significantly correlated with lymph node metastasis. In addition, correlation analysis results revealed that high Notch1 expression was significantly associated with high Slug, Snail, and N-cadherin expression and low E-cadherin expression in IDC. Furthermore, a high Snail expression was significantly associated with low E-cadherin expression, and a high Slug expression was found to be significantly associated with increased N-cadherin expression in patients with IDC. Hence, our study suggested that the Notch1-Snail/Slug-EMT axis may be implicated in the lymph node metastasis affecting patients with IDC.

Epithelial-mesenchymal transition markers in lymph node metastases and primary breast tumors - relation to dissemination and proliferation

Epithelial-mesenchymal transition (EMT) was shown to enhance metastatic abilities of cancer cells, but it remains elusive in clinical samples. Moreover, EMT is rarely studied in lymph node metastases (LNM), thus limiting our understanding of its role outside of the primary tumors (PT). We collected a set of samples including triplets - PT, circulating tumor cells (CTCs)-enriched blood samples and LNM from 108 early breast cancer patients. With immunohistochemistry we analyzed levels of EMT effectors - E-cadherin, vimentin and N-cadherin in LNM, central areas and margins of PT. Additionally, expression of EMT core regulators TWIST1, SNAI1, SNAI2 was measured with RT-qPCR. Patients with E-cadherin loss had CTCs in 45% of the cases in comparison to 23% with normal E-cadherin level (P = 0.05). Mesenchymal phenotype of CTCs-enriched blood fractions was five-times more frequent in patients with E-cadherin loss in PT compared to PT with normal E-cadherin levels (P = 0.01). Epithelial/mesenchymal status of matched samples at different stages of dissemination was frequently discordant, especially for pairs involving CTCs, indicating high plasticity of tumor cells. LNM showed increased expression of TWIST1, SNAI1, SNAI2 accompanied by decreased Ki67 labeling index, with median Ki67 of 15% in PT and 10% in LNM (P = 0.0002). Our findings demonstrate that E-cadherin loss, not only in PT margin, might lead to seeding of especially malignant CTCs with mesenchymal phenotype. In comparison to PT, cells in LNM re-express E-cadherin, upregulate EMT transcription factors and reduce cell division rate, which could be viewed as their long-term survival strategy.

The Role of TWIST in Ovarian Epithelial Cancers

Background

Epithelial-mesenchymal transition (EMT) is associated with tumor hypoxia. EMT is regulated, in part, by the action of TWIST, which inhibits of E-cadherin expression and may interfere with the p53 tumor-suppressor pathway.

Methods

We examined the expression of TWIST, E-cadherin, hypoxia-inducible factor 1α (HIF1α), and p53 by immunohistochemistry in 123 cases of ovarian epithelial cancers (OEC) to evaluate the role of TWIST in OEC. We assessed the association between protein expression and clinicopathologic parameters.

Results

The expression of TWIST, E-cadherin, HIF1α, and p53 proteins was found in 28.5%, 51.2%, 35.0%, and 29.3% of cases, respectively. TWIST expression was associated with higher histologic grade and unfavorable survival. TWIST expression was correlated with HIF1α expression and reduced E-cadherin expression. The altered HIF1α/TWIST/E-cadherin pathway was associated with lower overall survival (OS), while the co-expression of TWIST and p53 was correlated with lower progression-free survival. In the multivariate analyses, TWIST expression was an independent prognostic factor for OS.

Conclusions

Our data imply that TWIST expression could be a useful predictor of unfavorable prognosis for OEC. TWIST may affect the p53 tumor-suppressor pathway. Moreover, hypoxia-mediated EMT, which involves the HIF1α/TWIST/E-cadherin pathway may play an important role in the progression of OEC.

Tumor heterogeneity at protein level as an independent prognostic factor in endometrial cancer

Intratumor heterogeneity implies heterogeneous protein function, facilitating tumor adaptation which results in therapeutic failure. We hypothesized that tumor heterogeneity at protein level may influence the course of the disease. As a single biopsy might not represent the full biologic complexity of the tumor, we have analyzed immunohistochemically four different cores obtained from each primary tumor within the cohort of 364 patients with endometrial cancer (EC). The following proteins were examined: estrogen receptor 1 (ESR1), progesterone receptor, epidermal growth factor receptor, v-erb-b2 erythroblastic leukemia viral oncogene homolog 2, receptor tyrosine-protein kinase erbB-3, v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 4, phosphatidylinositol-4,5-bisphosphate 3-kinase, phosphorylated v-akt murine thymoma viral oncogene homolog 1, v-myc avian myelocytomatosis viral oncogene homolog, DNA topoisomerase II alpha 170 kDa (TOP2A), cyclin-dependent kinase inhibitor 2A (CDKN2A), tumor protein p53, RAD21 homolog, S. pombe, and runt-related transcription factor 1. Particularly strong correlation was found between TOP2A and CDKN2A heterogeneity and higher stage of the disease (P = .0002 and P = .0003, respectively). Most correlations with clinicopathologic data were observed for ESR1 heterogeneity that correlated with non-endometrioid carcinomas (P=.02), higher stage (P=.005), grade (P=.01), and the presence of metastases (P = .01). Thirty-nine (11.0%) patients were classified as “globally heterogeneous”. Cumulative tumor heterogeneity strongly correlated with the presence of metastases, higher stage, and higher grade of the disease (all P b .05). It also carried negative prognostic value (P=.0008). We show that the degree of heterogeneity in EC might serve as a clinically valid molecular marker.

SRC-1 and Twist1 expression positively correlates with a poor prognosis in human breast cancer

To evaluate the possible prognostic value of Steroid Receptor Coactivator-1 (SRC-1) and Twist1 expression in human breast cancer, we examined SRC-1 and Twist1 expression using immunohistochemistry on tissue microarray sections containing 137 breast cancer specimens. All patients were followed up for a median of 5 years following surgery. Survival curves were generated using the Kaplan-Meier method. Multivariate analysis was performed using the Cox proportional hazard regression model to assess the prognostic values. The results showed a positive correlation between SRC-1 and Twist1 expression at protein levels (P < 0.001). Also, SRC-1 expression positively correlated with HER2 expression (P = 0.024). The protein expression of Twist1 positively associated with lymph node metastasis (P < 0.001), but inversely correlated with PR status (P = 0.041). Patients with SRC-1 or Twist1-positive expression exhibited poorer overall survival (OS) and disease-free survival (DFS) than did those with SRC-1 or Twist1-negative expression (P < 0.05 for all). In addition, SRC-1-negativeive/Twist1-negative patients had the best OS and DFS (P < 0.01 for both). In multivariate survival analysis, SRC-1 expression, tumor stage, and PR were found to be independent prognostic factors related to OS (P = 0.019, < 0.001 and 0.02, respectively) and Twist1 expression, lymph node status and PR were independent predictors of DFS (P = 0.006, 0.001 and 0.029, respectively). These results suggest that a combined SRC-1/Twist1 expression status could improve the prognostic judgment for breast cancer patients.

Stability and prognostic value of Slug, Sox9 and Sox10 expression in breast cancers treated with neoadjuvant chemotherapy

BACKGROUND

Expression of transcription-factors as Slug and Sox9 was recently described to determine mammary stem-cell state. Sox10 was previously shown to be present also in breast cancer. Protein overexpression of Slug, Sox9 and Sox10 were associated with poor overall survival and with triple-negative phenotype in breast cancer. In this study we tested the stability of Slug, Sox9 and Sox10 expression during chemotherapy and addressed their prognostic role of in neoadjuvant treated primary breast-cancer and their correlation to pathological-response and overall survival.

METHODS

We analyzed immunohistochemical expression of Slug, Sox9 and Sox10 in tissue microarrays of 96 breast cancers prior to and after neoadjuvant chemotherapy. Expression was evaluated in invasive tumor cells and in tumor stroma and scored as 0, 1+, 2+ 3+. Expression-profile prior to and after chemotherapy was correlated to overall survival (Kaplan Meier) and with established clinico-pathological parameter.

RESULTS

Sox9, Sox10 and Slug were expressed in 82-96% of the tumor cells prior to chemotherapy. Slug was expressed in 97% of the cases in tumor stroma before therapy. Change in expression-profile after chemotherapy occurred only in Slug expression in tumor-cells (decreased from 82 to 51%, p = 0.0001, Fisher's exact test). The other markers showed no significant change after chemotherapy. Stromal Sox9 expression (0 to 2+) correlated to better overall survival after chemotherapy (p = 0.004) and reached almost statistical significance prior to chemotherapy (p = 0.065). There was no correlation between Sox9 and hormone-receptor expression. In multivariate-analysis, the stromal Sox9 expression after chemotherapy proved to be an independent and better prognostic marker than hormone-receptor status. Other clinico-pathological parameter (as HER2-status or pathological-stage) showed no correlation to the analyzed markers.

CONCLUSION

Strong stromal Sox9 expression in breast cancer after chemotherapy was found to bear negative prognostic information and was associated with shortened overall survival. Slug expression was significantly changed (reduced) in samples after neoadjuvant chemotherapy.

Slug is a predictor of poor prognosis in esophageal squamous cell carcinoma patients

Background

Slug, a regulator of epithelial mesenchymal transition, was identified to be differentially expressed in esophageal squamous cell carcinoma (ESCC) using cDNA microarrays by our laboratory. This study aimed to determine the clinical significance of Slug overexpression in ESCC and determine its correlation with clinicopathological parameters and disease prognosis for ESCC patients.

Methods

Immunohistochemical analysis of Slug expression was carried out in archived tissue sections from 91 ESCCs, 61 dysplastic and 47 histologically normal esophageal tissues. Slug immunopositivity in epithelial cells was correlated with clinicopathological parameters and disease prognosis over up to 7.5 years for ESCC patients.

Results

Increased expression of Slug was observed in esophageal dysplasia [cytoplasmic, 24/61 (39.3%) cases, p = 0.001, odd’s ratio (OR) = 4.7; nuclear, 11/61 (18%) cases, p < 0.001, OR = 1.36] in comparison with normal esophageal tissues. The Slug expression was further increased in ESCCs [cytoplasmic, 64/91 (70.3%) p < 0.001, OR = 10.0; nuclear, 27/91 (29.7%) p < 0.001, OR = 1.42]. Kaplan Meier survival analysis showed significant association of nuclear Slug accumulation with reduced disease free survival of ESCC patients (median disease free survival (DFS) = 6 months, as compared to those that did not show overexpression, DFS = 18 months; p = 0.006). In multivariate Cox regression analysis nuclear Slug expression [p= 0.005, Hazard’s ratio (HR) = 2.269, 95% CI = 1.289 - 3.996] emerged as the most significant independent predictor of poor prognosis for ESCC patients.

Conclusions

Alterations in Slug expression occur in early stages of development of ESCC and are sustained during disease progression. Slug may serve as a diagnostic biomarker and as a predictor of poor disease prognosis to identify ESCC patients that are likely to show recurrence of the disease.

CXCL13-CXCR5 co-expression regulates epithelial to mesenchymal transition of breast cancer cells during lymph node metastasis

We investigated the expression of -CXC chemokine ligand 13 (CXCL13) and its receptor -CXC chemokine receptor 5 (CXCR5) in 98 breast cancer (BC) patients with infiltrating duct carcinoma, out of which 56 were found lymph node metastasis (LNM) positive. Interestingly, co-expression of CXCL13 and CXCR5 showed a significant correlation with LNM. Since, epithelial to mesenchymal transition (EMT) is highly associated with metastasis we investigated EMT-inducing potential of CXCL13 in BC cell lines. In CXCL13-stimulated BC cells, expression of various mesenchymal markers (Vimentin, N-cadherin), EMT regulators (Snail, Slug), and matrix metalloproteinase-9 (MMP9) was increased, whereas the expression of epithelial marker E-cadherin was found to be decreased. In addition, expression of receptor activator of nuclear factor kappa-B ligand (RANKL), which is known to regulate MMP9 expression via Src activation, was also significantly increased after CXCL13 stimulation. Using specific protein kinase inhibitors, we confirmed that CXCL13 stimulated EMT and MMP9 expression via RANKL-Src axis in BC cell lines. To further validate this observation, we examined gene expression patterns in primary breast tumors and detected significantly higher expression of various mesenchymal markers and regulators in CXCL13-CXCR5 co-expressing patients. Therefore, this study showed the EMT-inducing potential of CXCL13 as well as demonstrated the prognostic value of CXCL13-CXCR5 co-expression in primary BC. Moreover, CXCL13-CXCR5-RANKL-Src axis may present a therapeutic target in LNM positive BC patients.

Heterogeneity of mesenchymal markers expression-molecular profiles of cancer cells disseminated by lymphatic and hematogenous routes in breast cancer

Breast cancers can metastasize via hematogenous and lymphatic routes, however in some patients only one type of metastases are detected, suggesting a certain proclivity in metastatic patterns. Since epithelial-mesenchymal transition (EMT) plays an important role in cancer dissemination it would be worthwhile to find if a specific profile of EMT gene expression exists that is related to either lymphatic or hematogenous dissemination. Our study aimed at evaluating gene expression profile of EMT-related markers in primary tumors (PT) and correlated them with the pattern of metastatic spread. From 99 early breast cancer patients peripheral blood samples (N = 99), matched PT (N = 47) and lymph node metastases (LNM; N = 22) were collected. Expression of TWIST1, SNAI1, SNAI2 and VIM was analyzed in those samples. Additionally expression of CK19, MGB1 and HER2 was measured in CTCs-enriched blood fractions (CTCs-EBF). Results were correlated with each other and with clinico-pathological data of the patients. Results show that the mesenchymal phenotype of CTCs-EBF correlated with poor clinico-pathological characteristics of the patients. Additionally, PT shared more similarities with LNM than with CTCs-EBF. Nevertheless, LNM showed increased expression of EMT-related markers than PT; and EMT itself in PT did not seem to be necessary for lymphatic dissemination.

Epithelial to mesenchymal transition markers are associated with an increased metastatic risk in primary cutaneous squamous cell carcinomas but are attenuated in lymph node metastases

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is the second most common malignancy in humans and approximately 5% metastasize, usually to regional lymph nodes. Epithelial to mesenchymal transition (EMT) is a process involving loss of intercellular adhesion, acquisition of a mesenchymal phenotype and enhanced migratory potential; epithelial markers, such as E-cadherin, are down-regulated and mesenchymal proteins (Vimentin), increased.

OBJECTIVE

To investigate the expression of EMT markers in metastatic SCC (MSCC) and their corresponding metastases, and to correlate them with clinico-pathological factors associated with an increased risk of metastasis.

METHODS

We performed a retrospective study that included 146 cSCC samples (51 primary non-metastatic, 56 primary metastatic, 39 lymphatic metastases). Immunohistochemistry for E-cadherin, Vimentin, Snail, beta-catenin, Twist, Zeb1 and Podoplanin was performed.

RESULTS

Loss of membranous E-cadherin was observed in 77% cSCCs, with no differences between MSCC and non-MSCC. Among the transcriptional factors controlling EMT, no significant Snail1 expression was detected. Twist, Zeb1, Vimentin, beta-catenin and Podoplanin were significantly overexpressed in MSCCs. Twist ectopic expression in SCC13 cells induced Zeb1, Vimentin and Podoplanin expression and E-cadherin delocalization. These changes resulted in a scattered migration pattern in vitro. Expression of EMT markers was decreased in the metastases when compared with the corresponding primary tumors.

CONCLUSION

These results suggest that a partial EMT, characterized by the expression of Twist but without a total E-cadherin depletion, is involved in the acquisition of invasive traits by cSCC, but the process is downregulated in lymph node metastases.

Biomarker expression and St Gallen molecular subtype classification in primary tumours, synchronous lymph node metastases and asynchronous relapses in primary breast cancer patients with 10 years' follow-up

Molecular profiles of asynchronous breast cancer metastases are of clinical relevance to individual patients' treatment, whereas the role of profiles in synchronous lymph node metastases is not defined. The present study aimed to assess individual biomarkers and molecular subtypes according to the St Gallen classification in primary breast tumours, synchronous lymph node metastases and asynchronous relapses and relate the results to 10-year breast cancer mortality (BCM). Tissue microarrays were constructed from archived tissue blocks of primary tumours (N = 524), synchronous lymph node metastases (N = 147) and asynchronous relapses (N = 36). The samples were evaluated by two independent pathologists according to oestrogen receptor (ER), progesterone receptor (PR), Ki67 and human epidermal growth factor receptor 2 (HER2) by immunohistochemistry and in situ hybridisation. The expression of biomarkers and molecular subtypes in the primary tumour was compared with that in the synchronous lymph node metastases and relapses, and related to 10-year BCM. Discordances were found between primary tumours and relapses (ER: p = 0.006, PR: p = 0.04, Ki67: p = 0.02, HER2: p = 0.02, St Gallen subtypes: p = 0.07) but not between primary tumours and metastatic lymph node. Prognostic information was gained by the molecular subtype classification in primary tumours and nodal metastases; triple negative subtype had the highest BCM compared with the luminal A subtype (primary tumours: HR 4.0; 95 % CI 2.0-8.2, p < 0.001, lymph node metastases: HR 3.5; 95 % CI 1.3-9.7, p = 0.02). When a shift in subtype inherence between primary tumour and metastatic lymph node was identified, the prognosis seemed to follow the subtype of the lymph node. Molecular profiles are not stable throughout tumour progression in breast cancer. Prognostic information for individual patients appears to be available from the analysis of biomarker expression in synchronous metastatic lymph nodes. The study supports biomarker analysis also in asynchronous relapses.