Immunohistochemical analysis of the expression of E-cadherin and ZEB1 in non-small cell lung cancer

Spatial and Temporal Relationship between Epithelial-Mesenchymal Transition (EMT) and Stem Cells in Cancer

BACKGROUND

Epithelial-mesenchymal transition (EMT) is often linked with carcinogenesis. However, EMT is also important for embryo development and only reactivates in cancer. Connecting how EMT occurs during embryonic development and in cancer could help us further understand the root mechanisms of cancer diseases.

CONTENT

There are key regulatory elements that contribute to EMT and the induction and maintenance of stem cell properties during embryogenesis, tissue regeneration, and carcinogenesis. Here, we explore the implications of EMT in the different stages of embryogenesis and tissue development. We especially highlight the necessity of EMT in the mesodermal formation and in neural crest cells. Through EMT, these cells gain epithelial-mesenchymal plasticity (EMP). With this transition, crucial morphological changes occur to progress through the metastatic cascade as well as tissue regeneration after an injury. Stem-like cells, including cancer stem cells, are generated from EMT and during this process upregulate factors necessary for stem cell maintenance. Hence, it is important to understand the key regulators allowing stem cell awakening in cancer, which increases plasticity and promotes treatment resistance, to develop strategies targeting this cell population and improve patient outcomes.

SUMMARY

EMT involves multifaceted regulation to allow the fluidity needed to facilitate adaptation. This regulatory mechanism, plasticity, involves many cooperating transcription factors. Additionally, posttranslational modifications, such as splicing, activate the correct isoforms for either epithelial or mesenchymal specificity. Moreover, epigenetic regulation also occurs, such as acetylation and methylation. Downstream signaling ultimately results in the EMT which promotes tissue generation/regeneration and cancer progression.

Aberrant expression of UBE2C in endometrial cancer and its correlation to epithelial mesenchymal transition

Ubiquitin-conjugating enzyme E2C (UBE2C), its overexpression promotes tumor progression, is a key component of the ubiquitin conjugating proteasome complex. Epithelial-mesenchymal transition, which is lost epithelial features and gained mesenchymal features in some epithelial cancers, is involved in epithelial cancers' invasiveness and metastasis. The aim of this study is to detect the expression of UBE2C, WNT5α, and E-cad in endometrial cancer (EC) and their clinical significance. The expression of UBE2C, WNT5α, and ZEB1 in 125 cases EC tissues were detected by immunohistochemistry. Patients clinicopathological, demography, and follow-up data were also collected. Positive rates of expression of UBE2C and ZEB1 were significantly higher in EC tissues when compared with the control tissues. The positive expression of UBE2C and ZEB1 were positively associated with tumor stages, local lymph node metastasis, and International Federation of Gynecology and Obstetrics (FIGO) stages. The positive rate of expression of WNT5a was significantly lower in EC tissues when compared with the control tissues. And positive expression of E-cad was inversely related to tumor stages, lymph node metastasis stages, and FIGO stages. Kaplan-Meier analyses demonstrated that positive expression of UBE2C or ZEB1 for EC patients had unfavorably overall survival time when compared with patients with negative expression of UBE2C or ZEB1. And EC patients with positive expression of WNT5a had favorably overall survival time when compared with EC patients with negative expression of WNT5a. Multivariate analysis demonstrated that positive expression UBE2C, WNT5α, and ZEB1, as well as FIGO stages were independent prognostic factors for EC patients. UBE2C, ZEB1, and WNT5a should be considered promising biomarkers for EC patients' prognosis.

Genetic and phenotypic determinants of morphologies in 3D cultures and xenografts of lung tumor cell lines

We previously proposed the classification of lung adenocarcinoma into two groups: the bronchial epithelial phenotype (BE phenotype) with high-level expressions of bronchial epithelial markers and actionable genetic abnormalities of tyrosine kinase receptors and the non-BE phenotype with low-level expressions of bronchial Bronchial epithelial (BE) epithelial markers and no actionable genetic abnormalities of tyrosine kinase receptors. Here, we performed a comprehensive analysis of tumor morphologies in 3D cultures and xenografts across a panel of lung cancer cell lines. First, we demonstrated that 40 lung cancer cell lines (23 BE and 17 non-BE) can be classified into three groups based on morphologies in 3D cultures on Matrigel: round (n = 31), stellate (n = 5), and grape-like (n = 4). The latter two morphologies were significantly frequent in the non-BE phenotype (1/23 BE, 8/17 non-BE, p = 0.0014), and the stellate morphology was only found in the non-BE phenotype. SMARCA4 mutations were significantly frequent in stellate-shaped cells (4/4 stellate, 4/34 non-stellate, p = 0.0001). Next, from the 40 cell lines, we successfully established 28 xenograft tumors (18 BE and 10 non-BE) in NOD/SCID mice and classified histological patterns of the xenograft tumors into three groups: solid (n = 20), small nests in desmoplasia (n = 4), and acinar/papillary (n = 4). The latter two patterns were characteristically found in the BE phenotype. The non-BE phenotype exhibited a solid pattern with significantly less content of alpha-SMA-positive fibroblasts (p = 0.0004) and collagen (p = 0.0006) than the BE phenotype. Thus, the morphology of the tumors in 3D cultures and xenografts, including stroma genesis, reflects the intrinsic properties of the cancer cell lines. Furthermore, this study serves as an excellent resource for lung adenocarcinoma cell lines, with clinically relevant information on molecular and morphological characteristics and drug sensitivity.

Post-Translational Modification of ZEB Family Members in Cancer Progression

Post-translational modification (PTM), the essential regulatory mechanisms of proteins, play essential roles in physiological and pathological processes. In addition, PTM functions in tumour development and progression. Zinc finger E-box binding homeobox (ZEB) family homeodomain transcription factors, such as ZEB1 and ZEB2, play a pivotal role in tumour progression and metastasis by induction epithelial-mesenchymal transition (EMT), with activation of stem cell traits, immune evasion and epigenetic reprogramming. However, the relationship between ZEB family members' post-translational modification (PTM) and tumourigenesis remains largely unknown. Therefore, we focussed on the PTM of ZEBs and potential therapeutic approaches in cancer progression. This review provides an overview of the diverse functions of ZEBs in cancer and the mechanisms and therapeutic implications that target ZEB family members' PTMs.

Nrf2 Downregulation Contributes to Epithelial-to-Mesenchymal Transition in Helicobacter pylori-Infected Cells

Simple Summary

Gastric cancer is mainly linked to Helicobacter pylori infection. It is therefore important to decipher the mechanisms involved in H. pylori-induced gastric carcinogenesis, and especially the early events. We have previously demonstrated that the infection leads to an epithelial-to-mesenchymal transition (EMT) favoring gastric carcinogenesis. H. pylori infection is also associated with high levels of oxidative stress. In this work, we aimed at investigating the modulation of Nrf2, a major regulator of cellular antioxidant response to oxidative stress, upon infection with H. pylori and to decipher its implication in EMT. We demonstrated that H. pylori-induced Nrf2 downregulation may participate in gastric cells’ EMT, one crucial tumorigenic event in gastric cancer. These results could pave the way for new therapeutic strategies using Nrf2 modulators to reduce gastric carcinogenesis associated with H. pylori infection.

Abstract

Background: Gastric cancer, the fifth most common cancer worldwide, is mainly linked to Helicobacter pylori infection. H. pylori induces chronic inflammation of the gastric mucosa associated with high oxidative stress. Our study aimed at assessing the implication of Nrf2, a major regulator of cellular redox homeostasis, in H. pylori-induced gastric carcinogenesis. Methods: Using three different gastric epithelial cell lines, a non-cancerous (HFE-145) and two different subtypes of gastric cancer (AGS and MKN74), we analyzed the modulation of Nrf2 expression over time. After invalidation of Nrf2 by CRISPR-cas9, we assessed its role in H. pylori-induced epithelial-to-mesenchymal transition (EMT). Finally, we evaluated the expression of Nrf2 and ZEB1, a central EMT transcription factor, in human gastric tissues. Results: We first demonstrated that the Nrf2 signaling pathway is differentially regulated depending on the infection stage. Rapidly and transiently activated, Nrf2 was downregulated 24 h post-infection in a VacA-dependent manner. We then demonstrated that Nrf2 invalidation leads to increased EMT, which is even exacerbated after H. pylori infection. Finally, Nrf2 expression tended to decrease in human patients’ gastric mucosa infected with H. pylori. Conclusions: Our work supports the hypothesis that Nrf2 downregulation upon H. pylori infection participates in EMT, one of the most important events in gastric carcinogenesis.

Expression and localisation of methylthioadenosine phosphorylase (MTAP) in oral squamous cell carcinoma and their significance in epithelial-to-mesenchymal transition

Methylthioadenosine phosphorylase (MTAP) is a rate-limiting enzyme in the methionine salvage pathway, which recycles one carbon unit that is lost during polyamine synthesis back into the methionine cycle. Although MTAP deficiency has been reported in various tumours, MTAP is overexpressed and might promote oncogenesis in other cancers, including prostate and colon cancer. Currently, little is known about the MTAP status of oral squamous cell carcinoma (OSCC). In this study, we immunohistochemically examined the expression of MTAP in surgically resected oral epithelial dysplasia (OED, n=7), carcinoma in situ (CIS) (n=16), and OSCC (n=118). In the normal epithelium, MTAP was only weakly expressed in the cytoplasm of the basal layer cells. In OED, CIS, and OSCC, MTAP was uniformly expressed in the cytoplasm of the dysplastic and cancer cells. In addition to cytoplasmic MTAP expression, 45 of 118 cases (38.1%) exhibited increased nuclear expression of MTAP in the cancer cells at the invasive front. Statistical analysis showed that the concomitant nuclear and cytoplasmic expression of MTAP was associated with a high budding score (p=0.0023); poor differentiation (p=0.0044); aggressive invasion patterns (p=0.0001); and features of epithelial-to-mesenchymal transition (EMT), such as loss of E-cadherin expression (p=0.0003) and upregulated expression of vimentin (p=0.0002), slug (p=0.0002), and laminin 5 (p<0.0001). High expression of protein arginine methyltransferase 1 or 5, the functions of which are reported to be inhibited in MTAP-deficient cancer, was associated with the concomitant nuclear and cytoplasmic expression of MTAP (p<0.0001). Concomitant nuclear and cytoplasmic expression of MTAP was marginally significantly associated with worse 5-year relapse-free survival (p=0.045). These findings suggest that MTAP not only plays a role in the oncogenesis of OSCC, but that it might also make it more aggressive by inducing EMT through its activity in the methionine salvage pathway.

Triptolide suppresses the growth and metastasis of non-small cell lung cancer by inhibiting β-catenin-mediated epithelial-mesenchymal transition

Non-small cell lung cancer (NSCLC) is characterized by a high incidence of metastasis and poor survival. As epithelial-mesenchymal transition (EMT) is well recognized as a major factor initiating tumor metastasis, developing EMT inhibitor could be a feasible treatment for metastatic NSCLC. Recent studies show that triptolide isolated from Tripterygium wilfordii Hook F attenuated the migration and invasion of breast cancer, colon carcinoma, and ovarian cancer cells, and EMT played important roles in this process. In the present study we investigated the effect of triptolide on the migration and invasion of NSCLC cell lines. We showed that triptolide (0.5, 1.0, 2.0 nM) concentration-dependently inhibited the migration and invasion of NCI-H1299 cells. Triptolide treatment concentration-dependently suppressed EMT in NCI-H1299 cells, evidenced by significantly elevated E-cadherin expression and reduced expression of ZEB1, vimentin, and slug. Furthermore, triptolide treatment suppressed β-catenin expression in NCI-H1299 and NCI-H460 cells, overexpression of β-catenin antagonized triptolide-caused inhibition on EMT, whereas knockout of β-catenin enhanced the inhibitory effect of triptolide on EMT. Administration of triptolide (0.75, 1.5 mg/kg per day, ip, every 2 days) for 18 days in NCI-H1299 xenograft mice dose-dependently suppressed the tumor growth, restrained EMT, and decreased lung metastasis, as evidence by significantly decreased expression of mesenchymal markers, increased expression of epithelial markers as well as reduced number of pulmonary lung metastatic foci. These results demonstrate that triptolide suppresses NSCLC metastasis by targeting EMT via reducing β-catenin expression. Our study implies that triptolide may be developed as a potential agent for the therapy of NSCLC metastasis.

Low PRRX1 expression and high ZEB1 expression are significantly correlated with epithelial-mesenchymal transition and tumor angiogenesis in non-small cell lung cancer

BACKGROUND

Paired related homeobox 1 (PRRX1) and zinc finger E-box binding homeobox 1 (ZEB1) have been observed to play a vital role in the epithelial-mesenchymal transition (EMT) process in different types of cancer. The microvessel density (MVD) is the most common indicator used to quantify angiogenesis. This study aimed to investigate expression of PRRX1 and ZEB1 in non-small cell lung cancer (NSCLC) and to explore associations between these factors and tumor prognosis, EMT markers and angiogenesis.

METHODS

Data for a total of 111 surgically resected NSCLC cases from January 2013 to December 2014 were collected. We used an immunohistochemical method to detect expression levels of PRRX1, ZEB1, and E-cadherin, and to assess MVD (marked by CD34 staining). SPSS 26.0 was employed to evaluate the connection between these factors and clinical and histopathological features, overall survival (OS) and tumor angiogenesis.

RESULTS

PRRX1 expression was obviously lower in tumor samples than in control samples. Low expression of PRRX1, which was more common in the high-MVD group than in the low-MVD group (P = .009), correlated positively with E-cadherin expression (P < .001). Additionally, we showed that ZEB1 was expressed at higher levels in tumor samples than in normal samples. High expression of ZEB1 was associated negatively with E-cadherin expression (P < .001) and positively associated with high MVD (P = .001). Based on Kaplan-Meier and multivariate survival analyses, we found that PRRX1, ZEB1, E-cadherin and the MVD had predictive value for OS in NSCLC patients.

CONCLUSIONS

These findings suggest that PRRX1 and ZEB1 may serve as novel prognostic biomarkers and potential therapeutic targets.

Clinical Impact of the Epithelial-Mesenchymal Transition in Lung Cancer as a Biomarker Assisting in Therapeutic Decisions

Lung cancer is one of the most common solid cancers and represents the leading cause of cancer death worldwide. Over the last decade, research on the epithelial-mesenchymal transition (EMT) in lung cancer has gained increasing attention. Here, we review clinical and histological features of non-small-cell lung cancer associated with EMT. We then aimed to establish potential clinical implications of EMT in current therapeutic options, including surgery, radiation, targeted therapy against oncogenic drivers, and immunotherapy.

FOXK1, Regulated by miR-365-3p, Promotes Cell Growth and EMT Indicates Unfavorable Prognosis in Breast Cancer

Background

Forkhead box K1 (FOXK1) is members of the FOX transcription factor family. Previous work has found out that FOXK1 promotes cell proliferation, migration and invasion in several cancers, such as gastric cancer, glioma cancer and lung cancer; however, the exact role of FOXK1 in breast cancer is still poorly known.

Methods

Here, the association between FOXK1 expression and the clinicopathological characteristics of patients with breast cancer was identified. To further decipher the functional roles of FOXK1, it was overexpressed or knocked down in MCF-7, MDA-MB-231 and MCF-10A cells. Cell Counting Kit-8, colony formation and cell cycle assays were performed to examine the proliferation of breast cancer cells. Moreover, wound-healing and Transwell invasion analyses were carried out to explore the effect of FOXK1 on breast cancer cell migration and invasion.

Results

Our findings discovered that FOXK1 promotes cell proliferation, migration and invasion in breast cancer. In addition, consistent with the previous report, FOXK1 also facilitates EMT in breast cancer. TargetScan was used to predict up-stream of FOXK1, indicating that miR-365-3p could regulate FOXK1 expression in breast cancer.

Conclusion

The findings of the present study demonstrated that miR-365-3p-FOXK1 axis plays a key role in breast cancer.

The diagnostic utility of zinc E-box 1 (ZEB1) transcription factor for identification of pulmonary sarcomatoid carcinoma in cytologic and surgical specimens

OBJECTIVE

Although uncommon, pulmonary sarcomatoid carcinoma carries a worse prognosis due to poor chemotherapeutic response. Currently, a histologic spindle and/or giant cell component indicates sarcomatoid differentiation, with zinc E-box binding homeobox 1 (ZEB1) implicated in promoting epithelial-mesenchymal transition. However, diagnostic use of ZEB1 in limited specimens, including cell block (CB) preparations, remains unclear.

MATERIALS AND METHODS

Pulmonary sarcomatoid (SARC, n = 15), typical (TC, n = 10) and atypical carcinoid (AC, n = 10), small cell (SCLC, n = 8) and large cell neuroendocrine carcinoma (LCNEC, n = 9), squamous cell carcinoma (SQ, n = 7), and adenocarcinoma (ADC, n = 7) CBs along with 69 SARCs, 20 TCs, 21 ACs, 9 SCLCs, 10 LCNECs, 71 SQs, 402 ADCs, 16 large cell carcinoma (LCC) and 17 other thoracic tumor (OT) surgical specimens between 2007 and 2018 were retrieved. ZEB1 (Sigma Aldrich, St. Louis, Mo and Novus Biological, Centennial, Colo) immunohistochemistry was graded 1+ to 3+, with ≥1+ and >5% staining considered positive.

RESULTS

Nuclear ZEB1 was seen in 80% SARC (12/15), 0% TC (0/10), 0% AC (0/10), 12.5% SCLC (1/8) and 11.1% LCNEC (1/9), 0% SQ (0/7), and 0% ADC (0/7) CBs. In surgical specimens, 75.4% SARCs (52/69), 0% TCs (0/20), 0% ACs (0/21), 11.1% SCLCs (1/9), 30% LCNECs (3/10), 0% SQs (0/71), 0.2% ADCs (1/402), 12.5% LCCs (2/16), and 11.8% OTs (2/17) demonstrated ZEB1. ZEB1 sensitivity and specificity in cytology and surgical specimens were 80% and 96.1%, and 75.4% and 98.1%, respectively.

CONCLUSIONS

ZEB1 is sensitive and highly specific for pulmonary sarcomatoid carcinoma in limited cytologic and surgical specimens. Diagnostic pitfalls include high-grade neuroendocrine tumors and large cell carcinoma, which are resolvable by morphologic considerations.

The association and prognostic impact of enhancer of zeste homologue 2 expression and epithelial-mesenchymal transition in resected lung adenocarcinoma

OBJECTIVES

Epithelial-mesenchymal transition (EMT) and the histone methyltransferase Enhancer of Zeste Homologue 2 (EZH2) are important regulators of lung cancer progression and metastasis. Although recent studies support the correlation between EZH2 expression and EMT, no reports have investigated their association using immunohistochemistry or explored their prognostic impact on lung adenocarcinoma. The aim of this study was to elucidate the association between EZH2 and EMT, and their prognostic significance.

METHODS

EZH2 and the EMT markers E-cadherin and Vimentin were examined by IHC in lung adenocarcinoma specimens that were resected from 2003-2012. Associations between EZH2 and EMT markers and their correlations with survival were analyzed.

RESULTS

We enrolled 350 patients, approximately 70% of whom were diagnosed as pathological stage I. The rates of positive E-cadherin, Vimentin, and EZH2 expression were 60.3%, 21.4%, and 52.0%, respectively. There was a significant positive correlation between EZH2 and Vimentin expression (p = 0.008), and EZH2 scores were higher in the Mesenchymal group (p = 0.030). In multivariate analysis, EZH2 was an independent predictor of Vimentin expression, and vice versa. EMT and EZH2 overexpression were significantly correlated with poor disease-free and overall survival. Furthermore, the Epithelial group with high EZH2 expression had significantly worse disease-free and overall survival. Positive staining for EMT markers was unfavorable regarding disease-free survival among patients with low EZH2 expression.

CONCLUSIONS

EMT and high EZH2 expression were associated with poor NSCLC prognoses. Vimentin is a key factor linking EMT and EZH2 in lung adenocarcinoma.

Clinical and Prognostic Significance of the Epithelial-Mesenchymal Transition in Stage IA Lung Adenocarcinoma: A Propensity Score-Matched Analysis

BACKGROUND

The epithelial-mesenchymal transition (EMT) describes the process through which cells lose epithelial characteristics and gain a mesenchymal phenotype. The EMT contributes to tumor invasion and cancer progression, and is associated with metastasis and poor survival of patients with non-small-cell lung cancer. However, little is known about the relationships between the EMT and the clinicopathologic characteristics of patients with stage IA lung adenocarcinoma.

PATIENTS AND METHODS

We conducted immunohistochemical analysis of the expression of the EMT markers E-cadherin and vimentin of specimens acquired from 183 consecutive patients with stage IA lung adenocarcinoma. The clinicopathologic significance of the association of the EMT status with E-cadherin and vimentin expression was analyzed after propensity score matching.

RESULTS

E-cadherin and vimentin were detected in 68.3% and 18.6% of stage IA lung adenocarcinomas, respectively. The presence of cells with EMT conversion was associated with older patient age. A propensity score-matched cohort (128 patients) was used for further analyses. Computed tomography revealed that tumors with EMT conversion showed solid-dominant nodules compared to those without conversion. Survival analysis after propensity score matching showed that the EMT correlated with poor disease-free survival (hazard ratio = 2.57, P = .0451) and overall survival (hazard ratio = 4.23, P = .0471). Multivariate analysis revealed that the EMT was an independent predictor of shorter disease-free survival.

CONCLUSION

The EMT was a significant predictor of poor prognosis of patients with stage IA lung adenocarcinoma. The EMT status may serve as an indicator for administering adjuvant therapy.

Targeting Oncogenic Nuclear Factor Kappa B Signaling with Redox-Active Agents for Cancer Treatment

SIGNIFICANCE

Nuclear factor kappa B (NF-κB) signaling is essential under physiologically relevant conditions. However, aberrant activation of this pathway plays a pertinent role in tumorigenesis and contributes to resistance. Recent Advances: The importance of the NF-κB pathway means that its targeting must be specific to avoid side effects. For many currently used therapeutics and those under development, the ability to generate reactive oxygen species (ROS) is a promising strategy.

CRITICAL ISSUES

As cancer cells exhibit greater ROS levels than their normal counterparts, they are more sensitive to additional ROS, which may be a potential therapeutic niche. It is known that ROS are involved in (i) the activation of NF-κB signaling, when in sublethal amounts; and (ii) high levels induce cytotoxicity resulting in apoptosis. Indeed, ROS-induced cytotoxicity is valuable for its capabilities in killing cancer cells, but establishing the potency of ROS for effective inhibition of NF-κB signaling is necessary. Indeed, some cancer treatments, currently used, activate NF-κB and may stimulate oncogenesis and confer resistance.

FUTURE DIRECTIONS

Thus, combinatorial approaches using ROS-generating agents alongside conventional therapeutics may prove an effective tactic to reduce NF-κB activity to kill cancer cells. One strategy is the use of thiosemicarbazones, which form redox-active metal complexes that generate high ROS levels to deliver potent antitumor activity. These agents also upregulate the metastasis suppressor, N-myc downstream regulated gene 1 (NDRG1), which functions as an NF-κB signaling inhibitor. It is proposed that targeting NF-κB signaling may proffer a new therapeutic niche to improve the efficacy of anticancer regimens.

miR-1 inhibits the proliferation of breast cancer stem cells by targeting EVI-1

Purpose

Breast cancer stem cells (BCSCs) have been regarded as the key factor for treatment failure in breast cancer. The abnormal expression of miRNAs plays a significant role in different tumor types. However, the role of miR-1 in breast cancer remains poorly understood. The purpose of this study was to evaluate the effects of miR-1 on the proliferation and apoptosis of BCSCs.

Materials and methods

CD44⁺/CD24^−/low/epithelial-specific antigen⁺ BCSCs were isolated by flow cytometry. Real-time PCR and Western blotting were used to determine the expression of miRNAs, mRNAs, and epithelial–mesenchymal transition (EMT)-related genes. Cell proliferation and apoptosis were measured using the Cell Counting Kit-8 assay and Annexin V-fluorescein isothiocyanate flow cytometry, respectively. Luciferase reporter assay was used to verify whether miR-1 targeted ecotropic virus integration-1 (EVI-1). The role of miR-1 in breast cancer in vivo was evaluated using BCSCs xenograft mouse models.

Results

In this study, we demonstrated that miR-1 was significantly downregulated in breast cancer tissues compared to the adjacent non-tumor tissues. The luciferase reporter assay verified that EVI-1 was a direct target of miR-1, and upregulation of miR-1 negatively correlated with the expression of EVI-1 in BCSCs at both the transcriptional and posttranslational levels. Furthermore, overexpression of miR-1 inhibited BCSCs proliferation and promoted apoptosis, which was reversed by the overexpression of EVI-1. In addition, we demonstrated that aberrant expression of miR-1 could regulate EMT-related genes in BCSCs. Finally, immunohistochemical staining demonstrated that EVI-1 expression was decreased in BCSCs tumors following intra-tumoral miR-1 agomir treatment compared to the control group.

Conclusion

miR-1 can negatively regulate the expression of EVI-1 and, thus, affect BCSCs proliferation, apoptosis, and EMT-related markers. Taken together, these findings demonstrate that miR-1 could be employed as a therapeutic strategy in the treatment of breast cancer.

SNAI2 and TWIST1 in lymph node progression in early stages of NSCLC patients

Lymph node metastasis is an important prognosis factor in non-small cell lung cancer (NSCLC) patients. The aim of this study was to investigate the role of epithelial to mesenchymal transition (EMT) in lymph node progression in the early stages of NSCLC. We studied a retrospective cohort of 160 consecutive surgically treated NSCLC patients with available frozen tumor samples for expression of EMT markers (CDH1, CTNNB1, CDH2, and VIMENTIN), inducers (TGFB1, c-MET, and CAIX), and transcription factors (EMT-TF: SNAI1, SNAI2, ZEB1, TWIST1, and TWIST2). Partial EMT was more frequent in N1-2 (N+) vs N0 patients (P < .01). TGFB1 (P = .02) as well as SNAI2 (P < .01) and TWIST1 (P = .04) were the most differentially expressed genes in N+ tumors. In this group, ZEB1 was correlated with all EMT inducers and other EMT-TFs were overexpressed depending on the inducers. CAIX was an independent prognostic factor for overall survival (IC 95% HR: 1.10-5.14, P = .03). Partial EMT is involved in lymph node progression of NSCLC patients and depends on the TGFβ pathway. EMT-TFs are differentially expressed depending on EMT inducers. CAIX might be a relevant prognostic marker in early stage NSCLC.

Multiregion gene expression profiling reveals heterogeneity in molecular subtypes and immunotherapy response signatures in lung cancer

Intra-tumor heterogeneity may be present at all molecular levels. Genomic intra-tumor heterogeneity at the exome level has been reported in many cancer types, but comprehensive gene expression intra-tumor heterogeneity has not been well studied. Here, we delineated the gene expression intra-tumor heterogeneity by exploring gene expression profiles of 35 tumor regions from 10 non-small cell lung cancer tumors (three or four regions/tumor), including adenocarcinoma, squamous cell carcinoma, large-cell carcinoma, and pleomorphic carcinoma of the lung. Using Affymetrix Gene 1.0 ST arrays, we generated the gene expression data for every sample. Inter-tumor heterogeneity was generally higher than intra-tumor heterogeneity, but some tumors showed a substantial level of intra-tumor heterogeneity. The analysis of various clinically relevant gene expression signatures including molecular subtype, epithelial-to-mesenchymal transition, and anti-PD-1 resistance signatures also revealed heterogeneity between different regions of the same tumor. The gene expression intra-tumor heterogeneity we observed was associated with heterogeneous tumor microenvironments represented by stromal and immune cells infiltrated. Our data suggest that RNA-based prognostic or predictive molecular tests should be carefully conducted in consideration of the gene expression intra-tumor heterogeneity.

SPOP, ZEB-1 and E-cadherin expression in clear cell renal cell carcinoma (cc-RCC): Clinicopathological and prognostic significance

BACKGROUND

Clear cell renal cell carcinoma (cc-RCC), is a serious cancer regarding; its fatality, liability for metastases and chemoresistance, so identification of recent therapeutic targets to improve the patients prognosis is needed. SPOP is a BTB/POZ domain containing speckle-type POZ protein, has been identified as an E3 ubiquitin ligase component. ZEB1 is an essential epithelial mesenchymal transition (EMT) activator; E-cadherin is a cell adhesion protein that had been detected in normal epithelial cells membrane.

AIM

Was to assess the tissue protein markers SPOP, ZEB1 & E-cadherin expressions in benign areas of neoplastic kidney specimens and in cc-RCC patients, then correlating their expression levels with patients clinicopathological and prognostic data.

METHODS

We evaluated SPOP, ZEB-1 & E-cadherin expression using immunohistochemistry in samples from 50 cc-RCC and 20 benign areas of neoplastic kidney specimens, then we followed our patients for 5 years and finally we have analyzed correlations between the levels of markers expressions with patients clinicopathological and prognostic criteria in cc-RCC.

RESULTS

Positive expression of SPOP & ZEB1 in addition to negative E- cadherin expression was detected in cc-RCC more than benign areas of neoplastic kidney specimens (p = 0.004 and p < 0.001 respectively). In cc-RCC Positive expression of SPOP, ZEB1 and negative E- cadherin expression was associated with higher grade (p = 0.006, 0.007 & <0.001 respectively), advanced AJCC stage (p = 0.013, 0.023 & <0.001 respectively), presence of L.N metastases (p = 0.002 = 0.010 and <0.001 respectively), distant metastases (p = 0.001, 0.003 & 0.035 respectively), poor PFS and OS rates (p < 0.001 and p = 0.013 respectively).

CONCLUSION

Positive expression of SPOP& ZEB1 in addition to negative E- cadherin are associated with poor prognosis in cc-RCC patients.

Expression level of microRNA-200c is associated with cell morphology in vitro and histological differentiation through regulation of ZEB1/2 and E-cadherin in gastric carcinoma

Scirrhous type gastric cancer is characterized by diffuse infiltration of poorly differentiated adenocarcinoma cells and poor prognosis. Although association of poorly differentiated histology with reduction in E-cadherin expression, as well as association of microRNA (miR)-200c with E-cadherin through regulation of ZEB1/2, has been reported, participation of miR-200c in gastric carcinogenesis is not fully understood. We used 6 cell lines originating from gastric cancers, and investigated levels of miR-200c along with its target mRNAs ZEB1/2 and E-cadherin by qRT-PCR. ZEB1 and E-cadherin protein expression was also assessed via western blotting. Furthermore, we investigated the expression levels of miR-200c by in situ hybridization, along with the expression of ZEB1 and E-cadherin by immunohistochemistry, in 97 gastric adenocarcinoma tissues. Inverse correlation between miR-200c and ZEB1 levels were obtained by qRT-PCR in cell lines (P<0.05). Cell lines with low miR-200c and high ZEB1 exhibited low E-cadherin expression in both qRT-PCR and western blotting, and exhibited spindle-shaped morphology, in contrast to round cell morphology in those cell lines with high miR-200c levels. Inverse correlations were also obtained between miR-200c and ZEB1 as well as between ZEB1 and E-cadherin levels in tissue samples (P<0.001). Cancer tissues with low miR-200c, high ZEB1, and low E-cadherin expression were associated with poorly differentiated histology, in contrast to tubular form in cancers with high miR-200c expression levels (P<0.001). Our data revealed that downregulation of miR-200c primarily regulated cell morphology by downregulation of E-cadherin through upregulation of ZEB1, leading to poorly differentiated histology in gastric cancer.

Foxk2 inhibits non-small cell lung cancer epithelial-mesenchymal transition and proliferation through the repression of different key target genes

Increasing evidence suggests that numerous fork-head transcription factors are required to repress the mammalian cells phenotype. Among them, Foxk2 is a ubiquitously expressed family member, but the role of Foxk2 in mediating tumor metastasis in non-small cell lung cancer has not been explored. In this investigation reduced Foxk2 expression was found in lung adenocarcinoma tissues compared with the adjacent non-tumor tissues, and was associated with better overall survival. Low expression was also found in the NSCLC cell lines such as A549, NCI-H520, H1299, H358 and H460 cells. Recombinant lentivirus expressing Foxk2 constructs or ShFoxk2 were developed and transfected into A549 cells or NCI-H520 cells, immunofluorescence assay, qRT-PCR, and western blot analysis were used to measure the change of the epithelial markers, E-cadherin and α-catenin, and mesenchymal markers N-cadherin and vimentin. Wound healing assay and Transwell assay were used to measure the relative cell invasion ability. MTT assay, Edu assay, and cell cycle distribution analysis were used to confirm the effect of Foxk2 on cell proliferation. ChIP-seq, qChIP, as well as luciferase reporter gene assays were used to detect the target genes regulated by Foxk2, Bioinformatics predicated the potential miRNAs that could target Foxk2. Our study demonstrated that Foxk2 played major roles in NSCLC EMT by directly targeting N-cadherin and Snail, we found that Foxk2 regulated NSCLC cell growth by suppressing the expression of cyclin D1 and CDK4, which suggested that Foxk2 might be a multifunctional regulator in NSCLC. The expression of Foxk2 may be regulated by miR-1271, which could serve as a promising therapeutic target for NSCLC.

MicroRNAs associated with increased AKT gene number in human lung carcinoma

MicroRNA (miRNA) expression profiles were examined in 3 groups of lung carcinomas that had been stratified by increases in AKT1 or AKT2 gene number. Microarray analysis using 2000 probes revealed 87 miRNAs that were up-regulated and 32 down-regulated miRNAs in carcinomas harboring amplification or high-level polysomy of the AKT1 (AKT1+), as well as 123 up-regulated and 83 down-regulated miRNAs in those of the AKT2 genes (AKT2+), in comparison with carcinomas harboring disomy of both (AKTd/d). In total, 182 miRNAs were up-regulated in AKT1+ or AKT2+, compared with AKTd/d. Among these, 28 miRNAs were up-regulated in both the AKT1+ and AKT2+ groups, with a log2 ratio between 1.02 and 3.71 relative to AKTd/d group, including all miR-200 family members. Quantitative real-time polymerase chain reaction showed that carcinomas exhibiting lymph vessel invasion had significantly lower expression of miR-200a (P=.0230) and miR-200b (P=.0168), regardless of the status of the AKT genes. Moreover, a detailed statistical analysis revealed that, in adenocarcinoma and in the early stage of carcinomas (pathologic stage I/II), expression of miR-200a was higher in the AKT2+ group compared with the AKT1+ group, and these differences were statistically significant (P=.0334 and P=.0239, respectively). However, the expression of miR-200a was not significantly correlated with the expression of its target, the zinc finger E-box-binding homeobox 1 (ZEB1; P=.3801) or E-cadherin (P=.2840), a marker of the epithelial-mesenchymal transition. These results suggest that AKT2 can regulate miR-200a in a histology- or stage-specific manner and that this regulation is independent of subsequent involvement of miR-200a in epithelial-mesenchymal transition.

ZEB1: at the crossroads of epithelial-mesenchymal transition, metastasis and therapy resistance

Zinc finger E-box binding homeobox 1 (ZEB1) is a transcription factor that promotes tumor invasion and metastasis by inducing epithelial-mesenchymal transition (EMT) in carcinoma cells. EMT not only plays an important role in embryonic development and malignant progression, but is also implicated in cancer therapy resistance. It has been hypothesized that carcinoma cells that have undergone EMT acquire cancer stem cell properties including self-renewal, chemoresistance and radioresistance. However, our recent data indicate that ZEB1 regulates radioresistance in breast cancer cells through an EMT-independent mechanism. In this Perspective, we review different mechanisms by which ZEB1 regulates tumor progression and treatment resistance. Based on studies by us and others, we propose that it is specific EMT inducers like ZEB1, but not the epithelial or mesenchymal state itself, that dictate cancer stem cell properties.

Wide expression of ZEB1 in sarcomatous component of spindle cell carcinoma of the esophagus

The pathogenesis of sarcomatous component in spindle cell carcinoma (SpCC) of the esophagus is unclear. To investigate the involvement of epithelial-mesenchymal transition (EMT) in sarcomatous differentiation, we performed immunohistochemistry for Slug, Twist, ZEB1, and ZEB2, transcription factors associated with EMT and E-cadherin, in 14 cases of SpCC of the esophagus. In order to verify the neoplastic nature of sarcomatous components, TP53 mutation status and protein expression were examined in each case. Nuclear ZEB1 expression was extensive in the sarcomatous component, greater than invasive front of carcinoma components (P < 0.0001). Membranous E-cadherin expression was mostly lost in sarcomatous cells in all cases (P < 0.0001). The p53 expression pattern was almost concordant between the two areas in all cases. TP53 mutation analysis revealed that seven cases harbored identical mutations in both components. One case had mutations only in the sarcomatous component. It is noteworthy that none of them harbored mutation in exon 5, unlike conventional esophageal squamous cell carcinoma. These findings show that ZEB1 are widely expressed in the sarcomatous area of SpCC of the esophagus, suggesting the involvement of EMT. The avoidance of exon 5 in terms of TP53 mutation may also be a feature of the tumor.