P-cadherin promotes liver metastasis and is associated with poor prognosis in colon cancer

The transcription factors Junb and Fosl2 cooperate to regulate Cdh3 expression in 15P-1 Sertoli cells

In Sertoli cells of the testis, cadherins (Cdh) are important cell-to-cell interaction proteins and contribute to the formation of the blood-testis barrier being essential for germ cells' protection. P-cadherin or Cdh3 is only expressed in Sertoli cells from embryonic to prepubertal development. Interestingly, the expression profile of Cdh3 correlates with that of activating protein-1 (AP-1) transcription factors during Sertoli cells development. To assess their potential implications in the regulation of Cdh3, different AP-1 transcription factors were overexpressed in 15P-1 Sertoli cells. We found that the overexpressions of Junb and Fosl2 activated Cdh3 promoter. ChIP-qPCR assay and luciferase reporter assay with 5' promoter deletions and site-directed mutagenesis confirmed the recruitment of Junb and Fosl2 to an AP-1 regulatory element at -47 bp in the proximal region of Cdh3 promoter in 15P-1 cells. These findings were further supported by histone modification markers and chromatin accessibility surrounding Cdh3 promoter in mouse testis. Moreover, the knockdowns of Junb and/or Fosl2 by siRNA decreased Cdh3 protein levels. Taken together, these data suggest that in 15P-1 Sertoli cells, the AP-1 family members Junb and Fosl2 are responsible for the regulation of Cdh3 expression, which requires the recruitment of both factors to the proximal region of the Cdh3 promoter.

Cell-adhesion Molecules as Key Mechanisms of Tumor Invasion: The Case of Breast Cancer

Cancer is a major health problem worldwide and the second leading cause of death following cardiovascular diseases. Breast cancer is the leading cause of mortality and morbidity among women and one of the most common malignant neoplasms prompt to metastatic disease. In the present review, the mechanisms of the major cell adhesion molecules involved in tumor invasion are discussed, focusing on the case of breast cancer. A non-systematic updated revision of the literature was performed in order to assemble information regarding the expression of the adhesion cell molecules associated with metastasis.

Association of β-Catenin, APC, SMAD3/4, Tp53, and Cyclin D1 Genes in Colorectal Cancer: A Systematic Review and Meta-Analysis

Objectives

Accumulating evidence indicates that the expression and/or variants of several genes play an essential role in the progress of colorectal cancer (CRC). The current study is a meta-analysis undertaken to estimate the prognosis and survival associated with CTNNB1/β-catenin, APC, Wnt, SMAD3/4, TP53, and Cyclin D1 genes among CRC patients.

Methods

The authors searched PubMed, EMBASE, and Science Direct for relevant reports published between 2000 and 2020 and analyzed them to determine any relationship between the (immunohistochemically/sequencing-detected) gene expression and variants of the selected genes and the survival of CRC patients.

Results

The analysis included 34,074 patients from 64 studies. To evaluate association, hazard ratios (HRs) were estimated for overall survival (OS) or disease-free survival (DFS), with a 95% confidence interval (CIs). Pooled results showed that β-catenin overexpression, APC mutation, SMAD-3 or 4 loss of expression, TP53 mutations, and Cyclin D1 expression were associated with shorter OS. β-Catenin overexpression (HR: 0.137 (95% CI: 0.131–0.406)), loss of expression of SMAD3 or 4 (HR: 0.449 (95% CI: 0.146–0.753)), the mutations of TP53 (HR: 0.179 (95% CI: 0.126–0.485)), and Cyclin D1 expression (HR: 0.485 (95% CI: 0.772–0.198)) also presented risk for shorter DFS.

Conclusions

The present meta-analysis indicates that overexpression or underexpression and variants of CTNNB1/β-catenin, APC, SMAD3/4, TP53, and Cyclin D1 genes potentially acted as unfavorable biomarkers for the prognosis of CRC. The Wnt gene was not associated with prognosis.

P-Cadherin Regulates Intestinal Epithelial Cell Migration and Mucosal Repair, but Is Dispensable for Colitis Associated Colon Cancer

Recurrent chronic mucosal inflammation, a characteristic of inflammatory bowel diseases (IBD), perturbs the intestinal epithelial homeostasis resulting in formation of mucosal wounds and, in most severe cases, leads to colitis-associated colon cancer (CAC). The altered structure of epithelial cell-cell adhesions is a hallmark of intestinal inflammation contributing to epithelial injury, repair, and tumorigenesis. P-cadherin is an important adhesion protein, poorly expressed in normal intestinal epithelial cells (IEC) but upregulated in inflamed and injured mucosa. The goal of this study was to investigate the roles of P-cadherin in regulating intestinal inflammation and CAC. P-cadherin expression was markedly induced in the colonic epithelium of human IBD patients and CAC tissues. The roles of P-cadherin were investigated in P-cadherin null mice using dextran sulfate sodium (DSS)-induced colitis and an azoxymethane (AOM)/DSS induced CAC. Although P-cadherin knockout did not affect the severity of acute DSS colitis, P-cadherin null mice exhibited faster recovery after colitis. No significant differences in the number of colonic tumors were observed in P-cadherin null and control mice. Consistently, the CRISPR/Cas9-mediated knockout of P-cadherin in human IEC accelerated epithelial wound healing without affecting cell proliferation. The accelerated migration of P-cadherin depleted IEC was driven by activation of Src kinases, Rac1 GTPase and myosin II motors and was accompanied by transcriptional reprogramming of the cells. Our findings highlight P-cadherin as a negative regulator of IEC motility in vitro and mucosal repair in vivo. In contrast, this protein is dispensable for IEC proliferation and CAC development.

Cadherin‐3 is a novel oncogenic biomarker with prognostic value in glioblastoma

Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. The prognosis of patients is very poor, with a median overall survival of ~ 15 months after diagnosis. Cadherin‐3 (also known as P‐cadherin), a cell–cell adhesion molecule encoded by the CDH3 gene, is deregulated in several cancer types, but its relevance in GBM is unknown. In this study, we investigated the functional roles, the associated molecular signatures, and the prognostic value of CDH3/P‐cadherin in this highly malignant brain tumor. CDH3/P‐cadherin mRNA and protein levels were evaluated in human glioma samples. Knockdown and overexpression models of P‐cadherin in GBM were used to evaluate its functional role in vitro and in vivo. CDH3‐associated gene signatures were identified by enrichment analyses and correlations. The impact of CDH3 in the survival of GBM patients was assessed in independent cohorts using both univariable and multivariable models. We found that P‐cadherin protein is expressed in a subset of gliomas, with an increased percentage of positive samples in grade IV tumors. Concordantly, CDH3 mRNA levels in glioma samples from The Cancer Genome Atlas (TCGA) database are increased in high‐grade gliomas. P‐cadherin displays oncogenic functions in multiple knockdown and overexpression GBM cell models by affecting cell viability, cell cycle, cell invasion, migration, and neurosphere formation capacity. Genes that were positively correlated with CDH3 are enriched for oncogenic pathways commonly activated in GBM. In vivo, GBM cells expressing high levels of P‐cadherin generate larger subcutaneous tumors and cause shorter survival of mice in an orthotopic intracranial model. Concomitantly, high CDH3 expression is predictive of shorter overall survival of GBM patients in independent cohorts. Together, our results show that CDH3/P‐cadherin expression is associated with aggressiveness features of GBM and poor patient prognosis, suggesting that it may be a novel therapeutic target for this deadly brain tumor.

ECM-Receptor Regulatory Network and Its Prognostic Role in Colorectal Cancer

Interactions of the extracellular matrix (ECM) and cellular receptors constitute one of the crucial pathways involved in colorectal cancer progression and metastasis. With the use of bioinformatics analysis, we comprehensively evaluated the prognostic information concentrated in the genes from this pathway. First, we constructed a ECM-receptor regulatory network by integrating the transcription factor (TF) and 5'-isomiR interaction databases with mRNA/miRNA-seq data from The Cancer Genome Atlas Colon Adenocarcinoma (TCGA-COAD). Notably, one-third of interactions mediated by 5'-isomiRs was represented by noncanonical isomiRs (isomiRs, whose 5'-end sequence did not match with the canonical miRBase version). Then, exhaustive search-based feature selection was used to fit prognostic signatures composed of nodes from the network for overall survival prediction. Two reliable prognostic signatures were identified and validated on the independent The Cancer Genome Atlas Rectum Adenocarcinoma (TCGA-READ) cohort. The first signature was made up by six genes, directly involved in ECM-receptor interaction: AGRN, DAG1, FN1, ITGA5, THBS3, and TNC (concordance index 0.61, logrank test p = 0.0164, 3-years ROC AUC = 0.68). The second hybrid signature was composed of three regulators: hsa-miR-32-5p, NR1H2, and SNAI1 (concordance index 0.64, logrank test p = 0.0229, 3-years ROC AUC = 0.71). While hsa-miR-32-5p exclusively regulated ECM-related genes (COL1A2 and ITGA5), NR1H2 and SNAI1 also targeted other pathways (adhesion, cell cycle, and cell division). Concordant distributions of the respective risk scores across four stages of colorectal cancer and adjacent normal mucosa additionally confirmed reliability of the models.

The expression and prognostic relevance of CDH3 in tongue squamous cell carcinoma

P-cadherin (CDH3) is a cell-to-cell adhesion molecule that regulates several cellular homeostatic processes in normal tissues. Lack of CDH3 expression is associated with aggressive behavior in oral squamous cell carcinoma (OSCC). Previous studies have shown that CDH3 is downregulated in high-grade OSCC and its reduced expression is predictive for poorer survival. The aim of this study was to evaluate the expression and prognostic relevance of CDH3 in tongue squamous cell carcinoma (TSCC). A retrospective series of 211 TSCC and 50 lymph node samples were stained immunohistochemically with polyclonal antibody (anti-CDH3). CDH3 expression was assessed semi-quantitatively with light microscopy. Fisher's exact test was used to compare patient and tumor characteristics, and the correlations were tested by Spearman correlation. Survival curves were drawn by the Kaplan-Meier method and analyzed by the log-rank test. Univariate and multivariate Cox regression was used to estimate the association between CDH3 expression and survival. CDH3 expression did not affect TSCC patient's disease-specific survival or overall survival. Strong CDH3 expression in the primary tumor predicted poor disease-specific and overall survival in patients with recurrent disease. CDH3 expression in lymph nodes without metastasis was negative in all cases. CDH3 expression was positive in all lymph node metastases with extranodal extension. In contrast to previous report about the prognostic value of CDH3 in OSCC, we were not able to validate the result in TSCC.

The role of cell surface proteins gene expression in diagnosis, prognosis, and drug resistance of colorectal cancer: In silico analysis and validation

Cell surface proteins (CSPs) are an important type of protein in different essential cell functions. This study aimed to distinguish overexpressed CSPs in colorectal cancer to investigate their biomarker, prognosis, and drug resistance potential. Raw data of three datasets including 1187 samples was downloaded then normalization and differential expression were performed. By the combination of the cancer genome atlas (TCGA) clinical data, survival analysis was carried out. Information of all CSPs was collected from cell surface protein atlas. The role of each candidate gene expression was investigated in drug resistance by CCEL and GDSC data from PharmacoGX. CRC samples including 30 tumor samples and adjacent normal were used to confirm data by RT-qPCR. Outcomes showed that 66 CSPs overexpressed in three datasets, and 146 CSPs expression associated with poor prognosis features in TCGA data that TIMP1 and QSOX2 can associate with poor patient survival independently. High-risk patients illustrated more fatality than low-risk patients based on the risk score calculated by the expression level of these genes. Receiver operating characteristic curve analysis showed that 39 CSPs as perfect biomarkers for diagnosis in CRC. Furthermore, QSOX2 and TIMP1 expression levels increased in tumor samples compared to adjacent normal samples. The Drug resistance analysis demonstrated ADAM12 and COL1A2 up-regulation among 66 overexpressed CSPs caused resistance to Venetoclax and Cyclophosphamide with a high estimate, respectively. Many CSPs are deregulated in CRC, and can be valuable candidates as biomarkers for diagnosis, prognosis, and drug resistance.

Regulation of cadherin dimerization by chemical fragments as a trigger to inhibit cell adhesion

Many cadherin family proteins are associated with diseases such as cancer. Since cell adhesion requires homodimerization of cadherin molecules, a small-molecule regulator of dimerization would have therapeutic potential. Herein, we describe identification of a P-cadherin-specific chemical fragment that inhibits P-cadherin-mediated cell adhesion. Although the identified molecule is a fragment compound, it binds to a cavity of P-cadherin that has not previously been targeted, indirectly prevents formation of hydrogen bonds necessary for formation of an intermediate called the X dimer and thus modulates the process of X dimerization. Our findings will impact on a strategy for regulation of protein-protein interactions and stepwise assembly of protein complexes using small molecules.

P-Cadherin and WNT5A expression in assessment of lymph node metastasis in oral squamous cell carcinoma

BACKGROUND

Oral cancer progression is a multi-step process in which adhesion molecules play a pivotal role in the development of recurrent, invasive, and distant metastasis. The aim of this study was to adopt prognostic biomarkers to assess the lymph node metastasis of OSCC that will facilitate in deciding the treatment modality by the surgeons.

OBJECTIVES

The objectives of the study were to assess the biological behaviour of OSCC by correlating the expression levels of P-Cadherin and WNT5A immunohistochemically.

METHODS

A total of 60 selected OSCCs cases (lymph node metastasis n = 30, non-metastatic n = 30) and 10 normal healthy controls were quantitatively and qualitatively analysed by immunohistochemistry for P-Cadherin and WNT5A. A survival analysis was also performed.

RESULTS

The expression levels of P-Cadherin and WNT5A in OSCC groups were statistically significant between metastatic and non-metastatic groups (p < 0.001). P-Cadherin and WNT5A expression in metastatic (lymph node metastasis) and non-metastatic cases showed a significant correlation coefficient of 0.753 at (p < 0.01). The present study also found that the aberrant expression (high) of P-Cadherin was associated with diminished survival of patients with metastatic OSCC.

CONCLUSION

The present study demonstrated the aberrant expression of P-Cadherin and WNT5A could serve as important prognosticator in OSCC.

CLINICAL RELEVANCE

P-Cadherin and WNT5A could be used as significant predictors of disease outcome.

A novel similarity score based on gene ranks to reveal genetic relationships among diseases

Knowledge of similarities among diseases can contribute to uncovering common genetic mechanisms. Based on ranked gene lists, a couple of similarity measures were proposed in the literature. Notice that they may suffer from the determination of cutoff or heavy computational load, we propose a novel similarity score SimSIP among diseases based on gene ranks. Simulation studies under various scenarios demonstrate that SimSIP has better performance than existing rank-based similarity measures. Application of SimSIP in gene expression data of 18 cancer types from The Cancer Genome Atlas shows that SimSIP is superior in clarifying the genetic relationships among diseases and demonstrates the tendency to cluster the histologically or anatomically related cancers together, which is analogous to the pan-cancer studies. Moreover, SimSIP with simpler form and faster computation is more robust for higher levels of noise than existing methods and provides a basis for future studies on genetic relationships among diseases. In addition, a measure MAG is developed to gauge the magnitude of association of anindividual gene with diseases. By using MAG the genes and biological processes significantly associated with colorectal cancer are detected.

Mucinous, endometrioid, and serous ovarian cancers with peritoneal dissemination are potent candidates for P-cadherin targeted therapy: a retrospective cohort study

BACKGROUND

Aberrant expression of P-cadherin has been reported in various cancers, and has been attracting attention as a target for cancer treatment. Ovarian cancer, the leading cause of death among gynecologic malignancies, is classified into four histological subtypes: serous, mucinous, endometrioid, and clear cell, and each has distinct biological behavior. Although a negative survival impact in serous ovarian cancer patients and some functional role in peritoneal dissemination have been reported, differences of P-cadherin expression in histological subtypes and the proportion and distribution of positive cells remain to be investigated. The aims of this study were to clarify the histological and distributional profiles of P-cadherin expression in ovarian cancer for development of target-therapy in near future.

METHODS

A total of 162 primary, 60 metastatic, and 8 recurrent tumors (all cases from 162 ovarian cancer patients) were enrolled in the study. Immunohistochemistry was performed for P-cadherin expression. Associations with clinicopathological characteristics and survival were analyzed.

RESULTS

P-cadherin expression showed a strong correlation with the FIGO stage, histological subtypes, positive peritoneal dissemination (P < 0.01), positive distant metastasis (P < 0.05), and trend toward negative overall survival probability (P = 0.050). P-cadherin was intensely and broadly expressed in mucinous, endometrioid, and serous subtypes (P < 0.01). Disseminated tumors demonstrated similar P-cadherin expression to primary tumors whereas metastatic lymph nodes demonstrated significantly decreased expression (P < 0.01).

CONCLUSIONS

Mucinous, endometrioid, and serous ovarian cancer patients accompanied with peritoneal disseminations are the most potent candidates for P-cadherin targeted drug delivery strategies. P-cadherin-targeted therapy may benefit and improve survival of poor-prognosis populations.

Preclinical Characterization of the Radioimmunoconjugate 111In or 90Y-FF-21101 Against a P-Cadherin-Expressing Tumor in a Mouse Xenograft Model and a Nonhuman Primate

P-cadherin is overexpressed in various cancers and can be a target for radioimmunotherapy. We investigated the preclinical pharmacokinetics and pharmacology of FF-21101, an ¹¹¹In- or ⁹⁰Y-conjugated monoclonal antibody against P-cadherin, to evaluate its clinical applications. Methods: The radiochemical purity, binding affinity, and in vitro serum stability of ¹¹¹In or ⁹⁰Y-labeled FF-21101 were evaluated. The pharmacokinetics of ¹¹¹In or ⁹⁰Y-FF-21101 were compared in normal mice. Tumor accumulation after ¹¹¹In-FF-21101 administration was investigated in mice bearing subcutaneous tumors with high (NCI-H1373), moderate (EBC-1), or no (A549) P-cadherin expression. The tumor suppression effect after a single intravenous injection of ⁹⁰Y-FF-21101 was assessed in NCI-H1373 and EBC-1 mouse xenograft models. The relationship between antibody dose and tumor accumulation was investigated in the NCI-H1373 mouse xenograft model. The absorbed radiation dose in humans after injection of ⁹⁰Y-FF-21101 was estimated using γ-camera images of cynomolgus monkeys. Results: The radiochemical purities of ¹¹¹In- and ⁹⁰Y-FF-21101 were 98.2% ± 2.5% (n = 9) and 99.3% ± 0.6% (n = 5), respectively. The dissociation constants were 1.083 nM for ¹¹¹In-FF-21101 and 1.367 nM for ⁹⁰Y-FF-21101. Both ¹¹¹In- and ⁹⁰Y-FF-21101 were stable in human serum after 96 h of incubation and exhibited similar pharmacokinetics in normal mice. The tumor accumulation of ¹¹¹In-FF-21101 was closely related to the intensity of P-cadherin expression in the cells. ⁹⁰Y-FF-21101 showed significant tumor growth inhibition, indicating that NCI-H1373 and EBC-1 recurrence was not observed after intravenous administration of 3.7 and 7.4 MBq, respectively of ⁹⁰Y-FF-21101 per animal. Tumor uptake in the mouse xenograft model and estimated absorbed radiation doses in the spleen of monkeys decreased with increasing antibody doses of ¹¹¹In-FF-21101. Conversely, the estimated absorbed radiation dose in the red marrow increased with increasing antibody dose. An antibody dose of 4.8 mg/m² was considered appropriate for humans, on the basis of efficacy and safety. The maximum tolerated administered activity of ⁹⁰Y-FF-21101 was estimated to be 2,886 MBq/human. Conclusion: FF-21101 radioimmunotherapy exhibited high antitumor affinity and antitumor efficacy in mouse xenograft models. Extrapolation of the pharmacokinetics in monkeys to humans suggests the potential for clinical application of FF-21101 for treating P-cadherin–expressing tumor.

Aberrant Expression of E-cadherin, N-cadherin, and P-cadherin in Clear Cell Renal Cell Carcinoma: Association With Adverse Clinicopathologic Factors and Poor Prognosis

OBJECTIVE

Aberrant expression of cadherins is known to be associated with tumor aggression. However, their role in clear cell renal cell carcinoma (CCRCC) is not well elucidated. This study investigated the expression of epithelial cadherin (E-cadherin), neural cadherin (N-cadherin), and placental cadherin (P-cadherin) in CCRCC, and assessed their prognostic significance and clinicopathologic association.

MATERIALS AND METHODS

We enrolled 254 patients with CCRCC who underwent radical or partial nephrectomy. E-cadherin, N-cadherin, and P-cadherin expression was evaluated by immunohistochemistry in a tissue microarray.

RESULTS

Low E-cadherin expression was associated with larger tumor size, lymphovascular invasion, higher pT stage, lymph node and distant metastasis, and higher stage. High N-cadherin expression was significantly associated with larger tumor size, higher nuclear grade, and tumor necrosis. P-cadherin expression was found to be significantly associated with higher nuclear grade, distant metastasis, and higher stage. Univariate analysis revealed that aberrant expression of the 3 cadherins was significantly related to shorter overall survival (OS). Loss of E-cadherin, high P-cadherin expression, and higher stage were independent prognostic factors for OS. For recurrence-free survival, lymphovascular invasion, high P-cadherin expression, and higher stage were independent prognostic factors. Cadherin switch was significantly associated with aggressive clinicopathologic factors and poor outcomes.

CONCLUSIONS

Aberrant expression of E-cadherin, N-cadherin, and P-cadherin was associated with adverse clinicopathologic factors and worse OS. Low E-cadherin and high P-cadherin expression were significantly associated with distant metastasis and independent prognostic factors. Therefore, cadherin expression may be used as a prognostic marker and therapeutic target, and cadherin switch plays an important role in CCRCC progression.

cGAMP inhibits tumor growth in colorectal cancer metastasis through the STING/STAT3 axis in a zebrafish xenograft model

The leading cause of mortality due to colorectal cancer (CRC) is highly associated with the development of liver metastases. Recently, we described cGAMP that is closely related to the metastatic state wherein the progress of metastatic tumors is associated with favorable outcomes in a zebrafish xenograft model. cGAMP was administered and the expression levels of type-I interferons were induced amongst tumor tissues to illuminate the overall measure of the induced STING/STAT3 axis in colorectal liver metastases. Furthermore, cGAMP-STING dependent STAT3 activation resulted in the inhibition of tumor cell proliferation, viability, and invasion in vitro. The subtotal reduction in tumor growth attributed to a large number of infiltrating inflammatory cells in vivo. We showed that cGAMP inhibited migration through angiogenesis by up-regulating IL-2, TNF-α, and IFN-γ, whereas STAT3 down-regulation inhibited CXCL8, BCL-2, and VEGFA expression. The importance of cGAMP in inhibiting the invasion front of CRC confirmed that the cGAMP dependent activation of STING/STAT3 axis played a key role in the inhibition of tumor progression.

Gene Selection for the Discrimination of Colorectal Cancer

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer worldwide. Cancer discrimination is a typical application of gene expression analysis using a microarray technique. However, microarray data suffer from the curse of dimensionality and usual imbalanced class distribution between the majority (tumor samples) and minority (normal samples) classes. Feature gene selection is necessary and important for cancer discrimination.

OBJECTIVES

To select feature genes for the discrimination of CRC.

METHODS

We improve the feature selection algorithm based on differential evolution, DEFSw by using RUSBoost classifier and weight accuracy instead of the common classifier and evaluation measure for selecting feature genes from imbalance data. We firstly extract differently expressed genes (DEGs) from the CRC dataset of the TCGA and then select the feature genes from the DEGs using the improved DEFSw algorithm. Finally, we validate the selected feature gene sets using independent datasets and retrieve the cancer related information for these genes based on text mining through the Coremine Medical online database.

RESULTS

We select out 16 single-gene feature sets for colorectal cancer discrimination and 19 single-gene feature sets only for colon cancer discrimination.

CONCLUSIONS

In summary, we find a series of high potential candidate biomarkers or signatures, which can discriminate either or both of colon cancer and rectal cancer with high sensitivity and specificity.

Cadherin Signaling in Cancer: Its Functions and Role as a Therapeutic Target

Cadherin family includes lists of transmembrane glycoproteins which mediate calcium-dependent cell-cell adhesion. Cadherin-mediated adhesion regulates cell growth and differentiation throughout life. Through the establishment of the cadherin-catenin complex, cadherins provide normal cell-cell adhesion and maintain homeostatic tissue architecture. In the process of cell recognition and adhesion, cadherins act as vital participators. As results, the disruption of cadherin signaling has significant implications on tumor formation and progression. Altered cadherin expression plays a vital role in tumorigenesis, tumor progression, angiogenesis, and tumor immune response. Based on ongoing research into the role of cadherin signaling in malignant tumors, cadherins are now being considered as potential targets for cancer therapies. This review will demonstrate the mechanisms of cadherin involvement in tumor progression, and consider the clinical significance of cadherins as therapeutic targets.

E-cadherin Beyond Structure: A Signaling Hub in Colon Homeostasis and Disease

E-cadherin is the core component of epithelial adherens junctions, essential for tissue development, differentiation, and maintenance. It is also fundamental for tissue barrier formation, a critical function of epithelial tissues. The colon or large intestine is lined by an epithelial monolayer that encompasses an E-cadherin-dependent barrier, critical for the homeostasis of the organ. Compromised barriers of the colonic epithelium lead to inflammation, fibrosis, and are commonly observed in colorectal cancer. In addition to its architectural role, E-cadherin is also considered a tumor suppressor in the colon, primarily a result of its opposing function to Wnt signaling, the predominant driver of colon tumorigenesis. Beyond these well-established traditional roles, several studies have portrayed an evolving role of E-cadherin as a signaling epicenter that regulates cell behavior in response to intra- and extra-cellular cues. Intriguingly, these recent findings also reveal tumor-promoting functions of E-cadherin in colon tumorigenesis and new interacting partners, opening future avenues of investigation. In this Review, we focus on these emerging aspects of E-cadherin signaling, and we discuss their implications in colon biology and disease.

Comparing progression molecular mechanisms between lung adenocarcinoma and lung squamous cell carcinoma based on genetic and epigenetic networks: big data mining and genome-wide systems identification

Non-small-cell lung cancer (NSCLC) is the predominant type of lung cancer in the world. Lung adenocarcinoma (LADC) and lung squamous cell carcinoma (LSCC) are subtypes of NSCLC. We usually regard them as different disease due to their unique molecular characteristics, distinct cells of origin and dissimilar clinical response. However, the differences of genetic and epigenetic progression mechanism between LADC and LSCC are complicated to analyze. Therefore, we applied systems biology approaches and big databases mining to construct genetic and epigenetic networks (GENs) with next-generation sequencing data of LADC and LSCC. In order to obtain the real GENs, system identification and system order detection are conducted on gene regulatory networks (GRNs) and protein-protein interaction networks (PPINs) for each stage of LADC and LSCC. The core GENs were extracted via principal network projection (PNP). Based on the ranking of projection values, we got the core pathways in respect of KEGG pathway. Compared with the core pathways, we found significant differences between microenvironments, dysregulations of miRNAs, epigenetic modifications on certain signaling transduction proteins and target genes in each stage of LADC and LSCC. Finally, we proposed six genetic and epigenetic multiple-molecule drugs to target essential biomarkers in each progression stage of LADC and LSCC, respectively.

P-cadherin mutations are associated with high basal Wnt activity and stemness in canine mammary tumor cell lines

Purpose: To find underlying mutations causing highly-activated Wnt activity in mammary tumor cell lines associated with rounded morphology indicative of stemness/EMT. Methods: Stemness of high Wnt cell lines was confirmed using qPCR on selected genes and microRNA profiling, followed by whole-exome sequencing of 3 high Wnt canine mammary tumor cell lines and 5 low/absent Wnt cell lines. Candidate genes were identified and their involvement in Wnt activity investigated using siRNA silencing. Results: The high Wnt cell lines had morphological and gene expression characteristics reminiscent of stemness. All individual cell lines had about 4000 mutations in the exome in comparison to the reference canine genome. The three high basal Wnt cell lines had 167 unique exome mutations. Seven of these mutations resulted in a SIFT score <0.2 of proteins related to Wnt signaling. However, gene silencing did not change the Wnt pathway activation. Renewed analysis with respect to putative relations to Wnt signaling revealed that P-cadherin (CDH3) had three mutations in the coding region of the extracellular domain and was associated with high Wnt signaling. Silencing by siRNA not only in lowered Wnt activity, but also decreased levels of phosphorylated cSRC and sP-cad, and changed cell morphology towards spindle cell appearance. Conclusion: It is concluded that expression of mutated CDH3 is associated with activation of cSRC, stabilization of ß-catenin and a rounded morphology related to a stemness/EMT phenotype. A decreased Wnt activity can be found also by cSRC inhibition, but CDH3 silencing has an additional effect on morphology indicating reversal of EMT.

Pre- and post-operative antibiotics in conjunction with cytoreductive surgery and heated intraperitoneal chemotherapy (HIPEC) should be considered for pseudomyxoma peritonei (PMP) treatment

Pseudomyxoma peritonei (PMP) is a subtype of peritoneal carcinomatosis that is traditionally treated by cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC). A growing body of evidence suggests that microbes are associated with various tumor types and have been found in organs and cavities that were once considered sterile. Prior and ongoing research from our consortium of PMP researchers strongly suggests that bacteria are associated with PMP tumors. While the significance of this association is unclear, in our opinion, further research is warranted to understand whether these bacteria contribute to the development, maintenance and/or progression of PMP. Elucidation of a possible causal role for bacteria in PMP could suggest a benefit for supplementation of antibiotics to current treatment protocols.

MEOX1 Promotes Tumor Progression and Predicts Poor Prognosis in Human Non-Small-Cell Lung Cancer

Background: MEOX1 is a homeobox transcriptional factor, and plays essential roles in regulating somite development. Our previous study indicated that MEOX1 is a critical molecular target in mesenchymal-like cancer cells in PTEN-deficient Trastuzumab resistant breast cancer. Despite the potential implication of MEOX1 for the cancer progression, no previous studies examined its level and clinical significance in lung cancer tissues. In this study, we aimed to detect the MEOX1 expression and correlate its level with clinical outcome in non-small-cell lung cancer patients (NSCLC). Methods: MEOX1 gene expression in lung cancer was examined by using the Oncomine database. MEOX1 protein levels were evaluated by IHC using the corresponding primary antibody on two different commercial lung cancer tissue arrays. siRNA knockdown was used to elucidate the function of MEOX1. Results: Analysis of the Oncomine datasets identified that an elevation of MEOX1 in gene amplification in lung cancer tissues in comparison to normal lung tissues. Immunohistochemistical analysis demonstrated that MEOX1 was localized predominantly in the nucleus, and positive rate was 67.3% (111/165) in NSCLC samples. Statistical analysis revealed high levels of MEOX1 significantly correlated with Lymph Node Metastasis and Stage. Kaplan-Meier survival analysis showed that high levels of MEOX1 were significantly associated with unfavorable survival in NSCLC patients, and MEOX1 nucleus staining had worse survival, than did patients with overall expression in lung squamous cell carcinoma patients. Multivariate Cox's regression analysis found that MEOX1 was an independent poor prognostic predictor for patients with NSCLC. Silencing of MEOX1 by specific SiRNA significantly inhibited H460 and H1299 cell proliferation and sphere formation in serum-free medium. Conclusions: Our results firstly indentified that high levels of MEOX1 especially nuclear staining was an independent prognostic factor for NSCLC, and it served a essential roles in the regulation of cell proliferation and colony formation in vitro. It may represent a potential target for the NSCLC treatment.

Antibody drug conjugates under investigation in phase I and phase II clinical trials for gastrointestinal cancer

INTRODUCTION

Antibody drug conjugates (ADCs) represent a developing class of anticancer therapeutics which are designed to selectively deliver a cytotoxic payload to tumors, while limiting systemic toxicity to healthy tissues. There are several ADCs which are currently in various stages of clinical development for the treatment of gastrointestinal malignancies.

AREAS COVERED

We discuss the biologic rationale and review the clinical experience with ADCs in the treatment of gastrointestinal malignancies, summarizing the pre-clinical and phase I/II clinical trial data that have been completed or are ongoing.

EXPERT OPINION

While there have been significant advances in the development of ADCs since they were first introduced, several challenges remain. These challenges include (i) the selection of an ideal antigen target which is tumor specific and internalized upon binding, (ii) selection of an antibody which has high affinity for its antigen target and low immunogenicity, (iii) selection of a potent payload which is cytotoxic at sub-nanomolar concentrations, and (iv) optimal design of a linker to confer ADC stability with limited off-site toxicity. Efforts are ongoing to address these issues and innovate the ADC technology to improve the safety and efficacy of these agents.

Genetics of metastasis: melanoma and other cancers

Melanoma is a malignant neoplasm of melanocytes that accounts for the majority of skin cancer deaths despite comprising less than 5% of all cutaneous malignancies. Its incidence has increased faster than that of any other cancer over the past half-century and the annual costs of treatment in the United States alone have risen rapidly. Although the majority of primary melanomas are cured with local excision, metastatic melanoma historically carries a grim prognosis, with a median survival of 9 months and a long-term survival rate of 10%. Given the urgent need to develop treatment strategies for metastatic melanoma and the explosion of genetic technologies over the past 20 years, there has been extensive research into the genetic alterations that cause melanocytes to become malignant. More recently, efforts have focused on the genetic changes that drive melanoma metastasis. This review aims to summarize the current knowledge of the genetics of primary cutaneous and ocular melanoma, the genetic changes associated with metastasis in melanoma and other cancer types, and non-genetic factors that may contribute to metastasis.

Detection of urinary survivin using a magnetic particles-based chemiluminescence immunoassay for the preliminary diagnosis of bladder cancer and renal cell carcinoma combined with LAPTM4B

The aim of the present study was to establish a simple step magnetic particles (MPs) based chemiluminescence enzyme immunoassay (CLEIA) for the detection of urinary survivin, and to investigate the diagnostic value of urinary survivin and lysosome-associated protein transmembrane-4β (LAPTM4B) in bladder cancer (BC) and renal cell carcinoma (RCC). The MPs-based CLEIA was developed on the basis of a double antibodies sandwich immunoreaction and luminol-H₂O₂ chemiluminescence system. The parameters of the method were optimized and evaluated. Urine samples were obtained from 200 BC patients, 81 RCC patients and 114 healthy individuals, and the MPs-based CLEIA method was employed to detect their urinary survivin. At the same time, the urinary LAPTM4B levels of the BC patients, RCC patients and the healthy controls were measured. The diagnostic efficiency of urinary survivin and LAPTM4B in BC and RCC was evaluated separately and jointly. A one-step MPs-based CLEIA for the detection of urinary survivin with good accuracy and precision was established. The signals were dependent on survivin concentrations in the range, 0 to 200 ng/ml, and the detection limit was 0.949 ng/ml. The areas under the receiver operating characteristic curves (AUC) were 0.771 in BC and 0.763 in RCC for urinary survivin. Urinary survivin was correlated with the tumor stage (P=0.002), lymph node metastasis (P=0.017), distant metastasis (P=0.005) and tumor size (P=0.02) of BC; however, no association with the clinicopathological parameters in RCC was observed. The AUCs for urinary LAPTM4B were 0.738 in BC and 0.704 in RCC, respectively. The AUCs for them combined were 0.842 in BC and 0.920 in RCC. The MPs-based CLEIA was performed well in the detection of urinary survivin. Urinary survivin and LAPTM4B could serve as potential biomarkers for the preliminary diagnosis of BC and RCC, and in combination they a achieved a greater diagnostic performance.

A CD3-bispecific molecule targeting P-cadherin demonstrates T cell-mediated regression of established solid tumors in mice

Strong evidence exists supporting the important role T cells play in the immune response against tumors. Still, the ability to initiate tumor-specific immune responses remains a challenge. Recent clinical trials suggest that bispecific antibody-mediated retargeted T cells are a promising therapeutic approach to eliminate hematopoietic tumors. However, this approach has not been validated in solid tumors. PF-06671008 is a dual-affinity retargeting (DART®)-bispecific protein engineered with enhanced pharmacokinetic properties to extend in vivo half-life, and designed to engage and activate endogenous polyclonal T cell populations via the CD3 complex in the presence of solid tumors expressing P-cadherin. This bispecific molecule elicited potent P-cadherin expression-dependent cytotoxic T cell activity across a range of tumor indications in vitro, and in vivo in tumor-bearing mice. Regression of established tumors in vivo was observed in both cell line and patient-derived xenograft models engrafted with circulating human T lymphocytes. Measurement of in vivo pharmacodynamic markers demonstrates PF-06671008-mediated T cell activation, infiltration and killing as the mechanism of tumor inhibition.

A core program of gene expression characterizes cancer metastases

While aberrant expression or splicing of metastasis genes conveys to cancers the ability to break through tissue barriers and disseminate, the genetic basis for organ preference in metastasis formation has remained incompletely understood. Utilizing the gene expression profiles from 653 GEO datasets, we investigate whether the signatures by diverse cancers in various metastatic sites display common features. We corroborate the meta-analysis in a murine model. Metastases are generally characterized by a core program of gene expression that induces the oxidative metabolism, activates vascularization/tissue remodeling, silences extracellular matrix interactions, and alters ion homeostasis. This program distinguishes metastases from their originating primary tumors as well as from their target host tissues. Site-selectivity is accomplished through specific components that adjust to the target micro-environment. The same functional groups of gene expression programs are activated in the metastases of B16-F10 cells to various target organs. It remains to be investigated whether these genetic signatures precede implantation and thus determine organ preference or are shaped by the target site and are thus a consequence of implantation. Conceivably, chemotherapy of disseminated cancer might be more efficacious if selected to match the genetic makeup of the metastases rather than the organ of origin by the primary tumor.

Insulin Mediated Activation of PI3K/Akt Signalling Pathway Modifies the Proteomic Cargo of Extracellular Vesicles

Epidemiological studies suggest that diabetes and obesity increases the risk of colorectal cancer (CRC) and lowers the patient survival rate. An important attribute in diabetes and obesity is the presence of high levels of growth factors including insulin in blood which can activate the PI3K/Akt signalling pathway. Dysregulation of PI3K/Akt signalling pathway leads to sustained proliferative signals thereby allowing the cells susceptible to cancer. Extracellular vesicles (EVs), secreted nanovesicles of endocytic origin, are implicated in mediating the transfer of oncogenic cargo in the tumour microenvironment. In this study, CRC cells were treated with insulin to activate PI3K/Akt signaling pathway. Insulin treatment significantly increased the number of EVs secreted by CRC cells. Furthermore, pAkt was exclusively packaged in EVs secreted by PI3K/Akt activated cells. Quantitative proteomics analysis confirmed that the protein cargo of EVs are modified upon activation of PI3K/Akt signaling pathway. Bioinformatics analysis highlighted the enrichment of proteins implicated in cell proliferation in EVs secreted by PI3K/Akt activated cells. Furthermore, incubation of EVs secreted by PI3K/Akt activated cells induced proliferation in recipient CRC cells. These findings suggest that EVs can amplify the signal provided by the growth factors in the tumor microenvironment and hence aid in cancer progression.

A novel FOXM1 isoform, FOXM1D, promotes epithelial-mesenchymal transition and metastasis through ROCKs activation in colorectal cancer

Epithelial-mesenchymal transition (EMT) is a critical event in metastasis of colorectal cancer (CRC). Rho/ROCKs signaling has a pivotal role in orchestrating actin cytoskeleton, leading to EMT and cancer invasion. However, the underlying mechanisms for ROCKs activation are not fully understood. Here, we identified FOXM1D, a novel isoform of Forkhead box M1 (FOXM1) that has a pivotal role in ROCKs activation by directly interacting with coiled-coil region of ROCK2. FOXM1D overexpression significantly polymerizes actin assembly and impairs E-cadherin expression, resulting in EMT and metastasis in xenograft mouse model and knockdown of FOXM1D has the opposite effect. Moreover, a high FOXM1D level correlates closely with clinical CRC metastasis. FOXM1D-induced ROCKs activation could be abrogated by the ROCKs inhibitors Y-27632 and fasudil. These observations indicate that the FOXM1D-ROCK2 interaction is crucial for Rho/ROCKs signaling and provide novel insight into actin cytoskeleton regulation and therapeutic potential for CRC metastasis.

Over-Expression of Alpha-Enolase as a Prognostic Biomarker in Patients with Pancreatic Cancer

Background: Alpha-enolase is an important glycolytic enzyme, and its aberrant expression has been associated with multiple tumor progression. However, few studies investigated the expression of alpha-enolase and its clinical significance in pancreatic cancer (PC). Objectives: To evaluate alpha-enolase level in PC tissues by immunohistochemical (IHC) analysis, and investigate the association of alpha-enolase expression with clinicopathologic features. Methods: The alpha-enolase levels in pancreatic cancer tissues were analyzed by using the Oncomine database. The expression of alpha-enolase, Ki67 and p53 in pancreatic cancer and adjacent normal tissues were evaluated by IHC using the corresponding primary antibodies on the commercial tissue arrays. We also examined their association with clinicopathologic parameters, and explored their prognostic value in PC. Results: We identified an elevation of alpha-enolase mRNA level in pancreatic cancer independent datasets from Oncomine. IHC analysis showed that alpha-enolase protein levels were elevated in 47% (n=100) PC tissue samples, but there was weak or no staining in the normal tissues. Statistical analysis revealed that high levels of alpha-enolase were significantly associated with Stage and Lymph node metastasis. Correlation analysis indicated that over-expression of alpha-enolase was positively associated with Ki67 expression and inversely correlated with p53 expression. Furthermore, membranous expression of alpha-enolase was also observed in 29.8% (14/47) total alpha-enolase positive samples, and was significantly associated with Lymph node metastasis. Kaplan-Meier survival analysis demonstrated that high total alpha-enolase expression was significantly associated with unfavorable survival, while membranous alpha-enolase expression was significantly associated with better survival of PC patients. Multivariate Cox analysis demonstrated that total alpha-enolase expression was an independent prognostic factor for PC patients. Conclusions: Our results suggested that alpha-enolase level was significantly elevated in pancreatic cancer tissues, which was closely associated with PC progression. It might be a candidate target for targeted pancreatic cancer treatments.

Nuclear expression and/or reduced membranous expression of β-catenin correlate with poor prognosis in colorectal carcinoma: A meta-analysis

BACKGROUND

The differential subcellular localizations of β-catenin (including membrane, cytoplasm, and nucleus) play different roles in the progression of colorectal cancer (CRC). However, the correlation between each subcellular localization of β-catenin and the prognosis of CRC patients remains undetermined.

METHODS

Systematic strategies were applied to search for eligible published studies in the PubMed, Embase, and Web of Science databases. The correlation between each subcellular localizations of β-catenin expression and patients' clinicopathological features or prognosis was analyzed.

RESULTS

Finally, this meta-analysis, including 6238 cases from 34 studies, revealed that β-catenin overexpression in the nucleus (HR: 1.50[95% CI: 1.08-2.10]) or reduced expression of β-catenin in the membrane (HR: 1.33[95% CI: 1.15-1.54]) significantly correlated with lower 5-year overall survival (OS). Conversely, overexpression of β-catenin in the cytoplasm (HR: 1.00[95% CI: 0.85-1.18]) did not show significant association with 5-year OS.

CONCLUSION

This study suggested that β-catenin overexpression in the nucleus or reduced expression in the membrane, but not its overexpression in cytoplasm, could serve as a valuable prognostic predictor for CRC. However, additional large and well-designed prospective studies are required to verify our results.

The Preoperative Peripheral Blood Monocyte Count Is Associated with Liver Metastasis and Overall Survival in Colorectal Cancer Patients

Background

Colorectal cancer (CRC) is the third most common malignancy in males and the second most common in females worldwide. Distant metastases have a strong negative impact on the prognosis of CRC patients. The most common site of CRC metastases is the liver. Both disease progression and metastasis have been related to the patient’s peripheral blood monocyte count. We therefore performed a case-control study to assess the relationship between the preoperative peripheral blood monocyte count and colorectal liver metastases (CRLM).

Methods

Clinical data from 117 patients with colon cancer and 93 with rectal cancer who were admitted to the Chinese People’s Liberation Army General Hospital (Beijing, China) between December 2003 and May 2015 were analysed retrospectively, with the permission of both the patients and the hospital.

Results

Preoperative peripheral blood monocyte counts, the T and N classifications of the primary tumour and its primary site differed significantly between the two groups (P < 0.001, P < 0.001, P = 0.002, P < 0.001), whereas there were no differences in the sex, age, degree of tumour differentiation or largest tumour diameter. Lymph node metastasis and a high preoperative peripheral blood monocyte count were independent risk factors for liver metastasis (OR: 2.178, 95%CI: 1.148~4.134, P = 0.017; OR: 12.422, 95%CI: 5.076~30.398, P < 0.001), although the risk was lower in patients with rectal versus colon cancer (OR: 0.078, 95%CI: 0.020~0.309, P < 0.001). Primary tumour site (P<0.001), degree of tumour differentiation (P = 0.009), T, N and M classifications, TNM staging and preoperative monocyte counts (P<0.001) were associated with the 5-year overall survival (OS) of CRC patients. A preoperative peripheral blood monocyte count > 0.505 × 10⁹ cells/L, high T classification and liver metastasis were independent risk factors for 5-year OS (RR: 2.737, 95% CI: 1.573~ 4.764, P <0.001; RR: 2.687, 95%CI: 1.498~4.820, P = 0.001; RR: 4.928, 95%CI: 2.871~8.457, P < 0.001).

Conclusions

The demonstrated association between preoperative peripheral blood monocyte count and liver metastasis in patients with CRC recommends the former as a useful predictor of postoperative prognosis in CRC patients.

Expression of E-, P- and N-Cadherin and Its Clinical Significance in Cervical Squamous Cell Carcinoma and Precancerous Lesions

Aberrant expression of classical cadherins has been observed in tumor invasion and metastasis, but its involvement in cervical carcinogenesis and cancer progression is not clear. We investigated E-, P- and N-cadherin expression and its significance in cervical squamous cell carcinoma (SCC) and cervical intraepithelial neoplasia (CIN). This retrospective study enrolled 508 patients admitted to Women's Hospital, School of Medicine, Zhejiang University with cervical lesions between January 2006 and December 2010. Immunochemical staining was performed in 98 samples of normal cervical epithelium (NC), 283 of CIN, and 127 of early-stage SCC. The association of cadherin staining with clinical characteristics and survival of the patients was evaluated by univariate and multivariate analysis. We found gradients of decreasing E-cadherin expression and increasing P-cadherin expression from NC through CIN to SCC. Aberrant E-cadherin and P-cadherin expression were significantly associated with clinical parameters indicating poor prognosis and shorter patient survival. Interestingly, we found very low levels of positive N-cadherin expression in CIN and SCC tissues that were not related to CIN or cancer. Pearson chi-square tests showed that E-cadherin expression in SCC was inversely correlated with P-cadherin expression (E-P switch), and was not correlated with N-cadherin expression. More important, patients with tissues exhibiting an E-P switch in expression had highly aggressive phenotypes and poorer prognosis than those without E-P switch expression. Our findings suggest that E-cadherin and P-cadherin, but not N-cadherin staining, might be useful in diagnosing CIN and for predicting prognosis in patients with early-stage SCC.

Serum haptoglobin as a novel molecular biomarker predicting colorectal cancer hepatic metastasis

Early detection of liver metastasis is important for improving colorectal cancer (CRC) patient survival. Our previous studies showed haptoglobin was highly expressed in primary CRC tissues, especially in heterochronous metastatic cases. Here, we assessed the potential of serum haptoglobin (sHP) as a biomarker for early detection of CRC liver metastasis by evaluating the sHP in 475 CRC patients and 152 healthy volunteers. In the training set (250 cases), sHP level in CRC-M1 (1773.18 ± 690.25 ng/mL) were significantly increased as compared to in CRC-M0 (1544.37 ± 1497.65 ng/mL) or healthy (917.76 ± 571.59 ng/mL). And the high sHP level was correlated with poor survival. Logistic regression analysis revealed that sHP, serum carcinoembryonic antigen (sCEA) and serum carbohydrate antigen 19.9 (sCA19.9) level were the significant parameters for detecting liver metastasis. In leave-one-out-cross-validation, these three markers resulted in 89.1% sensitivity and 85.8% specificity for hepatic metastasis detection. In an independent test set (225 cases), receiver operating characteristic curve analysis of sHP in CRC liver metastasis showed an area under the curve of 0.735, with a sensitivity of 87.2% and a specificity of 59.9%. Combination of sHP, sCEA and sCA19.9 improved diagnostic accuracy to 0.880, with a sensitivity of 88.5% and a specificity of 87.8%. Silencing of HP by specific shRNA significantly inhibited the LOVO and SW620 cell invasion, and suppressed xenograft tumor invasive growth. In summary, these results demonstrate that sHP is associated with poor prognosis of CRC patients and that HP promotes colorectal cancer cell invasion. sHP combining with sCA19.9 and sCEA may be used as accurate predictors of CRC liver metastasis.

P-cadherin and the journey to cancer metastasis

P-cadherin is a classical cell-to-cell adhesion molecule with a homeostatic function in several normal tissues. However, its behaviour in the malignant setting is notably dependent on the cellular context. In some tumour models, such as melanoma and oral squamous cell carcinoma, P-cadherin acts as a tumour suppressor, since its absence is associated with a more aggressive cancer cell phenotype; nevertheless, the overexpression of this molecule is linked to significant tumour promoting effects in the breast, ovarian, prostate, endometrial, skin, gastric, pancreas and colon neoplasms. Herein, we review the role of P-cadherin in cancer cell invasion, as well as in loco-regional and distant metastatic dissemination. We focus in P-cadherin signalling pathways that are activated to induce invasion and metastasis, as well as cancer stem cell properties. The signalling network downstream of P-cadherin is notably dependent on the cellular and tissue context and includes the activation of integrin molecules, receptor tyrosine kinases, small molecule GTPases, EMT transcription factors, and crosstalk with other cadherin family members. As new oncogenic molecular pathways mediated by P-cadherin are uncovered, putative therapeutic options can be tested, which will allow for the targeting of invasion or metastatic disease, depending on the tumour model.

Significance of P-cadherin overexpression and possible mechanism of its regulation in intrahepatic cholangiocarcinoma and pancreatic cancer

It has become evident that P-cadherin, one of the classical cadherins, contributes to the malignant behavior of several types of cancer. In this study, we analyzed the expression of P-cadherin and its clinicopathological and prognostic values in intrahepatic cholangiocarcinoma (ICC) and pancreatic cancer. Furthermore, we investigated the functional role of P-cadherin in these cancer cells by knockdown and overexpression in vitro and by analyzing the correlation between the P-cadherin expression and its promoter methylation status. Thirty of 59 ICC cases (51%) and 36 of 73 pancreatic cancer cases (49%) stained positive for P-cadherin with mainly membranous distribution in tumor cells by immunohistochemistry. P-cadherin expression was significantly correlated with several clinicopathological factors, which reflect tumor behavior, and was identified as an independent adverse prognostic factor for disease-free survival in patients with ICC (relative risk [RR] 2.93, P = 0.04) and pancreatic cancer (RR 2.68, P = 0.005) via multivariate analyses. P-cadherin downregulation by siRNA suppressed migration and invasion, and P-cadherin overexpression induced the opposite effects in both ICC and pancreatic cancer cells, without any effects on cell proliferation. P-cadherin expression was related to its promoter methylation status in both cell lines and cancer tissues. In summary, P-cadherin overexpression may serve as a useful biomarker of invasive phenotype and poor prognosis; P-cadherin expression was found to be regulated by its promoter methylation. These results suggest that P-cadherin represents a novel therapeutic target for the treatment of ICC and pancreatic cancer.

Positive MACC1 expression correlates with invasive behaviors and postoperative liver metastasis in colon cancer

OBJECTIVE

Metastasis-associated in colon cancer-1 (MACC1), a new gene associated with primary and metastatic colon cancer, promotes tumor cell growth as well as the development of distant metastasis. The aim of this study is to investigate the expression of MACC1 protein in colon cancer and its association with clinicopathological parameters and postoperative liver metastasis.

MATERIALS AND METHODS

Expression of MACC1 protein was detected immunohistochemically in paraffin-embedded specimens of 96 cases of colon cancer. Relationship between MACC1 protein expression and clinicopathological parameters, postoperative liver metastasis were analyzed.

RESULTS

Immunohistochemistry examination showed that MACC1 protein expression was significantly more abundant in colon cancer tissues than in normal colon tissues (P = 0.038), Positive rate of MACC1 expression in colon cancer tissues was increased significantly in patients with lymph node metastases (P = 0.001) and higher T stages (P = 0.006). Postoperative live metastasis-free survival period was significantly longer in negative MACC1 expression group than that of positive MACC1 expression group (36.4 ± 2.85 vs. 28.6 ± 2.02 months, P = 0.014). Multivariate analysis showed that MACC1 expression level is an independent prognostic factor for postoperative live metastasis-free survival (95% confidence interval [CI] =1.32-3.38, P = 0.006).

CONCLUSIONS

Our results suggest that MACC1 expression level might play an important role in colon cancer invasion and MACC1 expression level is an independent biomarker for postoperative liver metastasis in patients with colon cancer.

Cancer cells remodel themselves and vasculature to overcome the endothelial barrier

Metastasis refers to the spread of cancer cells from a primary tumor to distant organs mostly via the bloodstream. During the metastatic process, cancer cells invade blood vessels to enter circulation, and later exit the vasculature at a distant site. Endothelial cells that line blood vessels normally serve as a barrier to the movement of cells into or out of the blood. It is thus critical to understand how metastatic cancer cells overcome the endothelial barrier. Epithelial cancer cells acquire increased motility and invasiveness through epithelial-to-mesenchymal transition (EMT), which enables them to move toward vasculature. Cancer cells also express a variety of adhesion molecules that allow them to attach to vascular endothelium. Finally, cancer cells secrete or induce growth factors and cytokines to actively prompt vascular hyperpermeability that compromises endothelial barrier function and facilitates transmigration of cancer cells through the vascular wall. Elucidation of the mechanisms underlying metastatic dissemination may help develop new anti-metastasis therapeutics.

Overexpression of miR-223 correlates with tumor metastasis and poor prognosis in patients with colorectal cancer

The purpose of the study was to investigate microRNA-223 (miR-223) expression in colorectal cancer (CRC) and its relationship with tumorigenesis and disease prognosis. Quantitative real-time PCR was used to measure levels of miR-223 in tumor samples and adjacent non-cancerous tissues from 62 patients undergoing radical resection for the treatment of CRC. The associations between miR-223 expression and patient age, sex, as well as clinicopathologic parameters, such as tumor size, differentiation, location, invasion depth, metastasis, tumor-node-metastasis (TNM) stage, and overall patient survival, were analyzed by Mann-Whitney U and Kruskal-Wallis tests. Kaplan-Meier method and Cox proportional hazards regression analyses were performed to estimate the prognostic factors for patient survival prediction. The expression of miR-223 was significantly upregulated in CRC tissues compared with adjacent non-cancerous tissues (P < 0.05). This overexpression was associated with TNM stage and lymph node and distant metastases, (P < 0.05). Moreover, Kaplan-Meier analysis demonstrated that patients with high miR-223 expression had a poorer overall survival (OS) than those with low miR-223 expression (P = 0.002). Univariate analysis revealed a statistically significant correlation between OS and miR-223 level, histology grade, metastasis and TNM stage (P < 0.001). Furthermore, miR-223 levels and histology grade were independently associated with OS (HR 0.204, 95 % CI 0.101-0.415, P < 0.05 and HR 2.252, 95 % CI 1.429-3.546, P < 0.05, respectively). The overexpression of miR-223 may play an important role in the progression of CRC and can be used as an independent factor to determine CRC prognosis.

Excess PLAC8 promotes an unconventional ERK2-dependent EMT in colon cancer

The epithelial-to-mesenchymal transition (EMT) transcriptional program is characterized by repression of E-cadherin (CDH1) and induction of N-cadherin (CDH2), and mesenchymal genes like vimentin (VIM). Placenta-specific 8 (PLAC8) has been implicated in colon cancer; however, how PLAC8 contributes to disease is unknown, and endogenous PLAC8 protein has not been studied. We analyzed zebrafish and human tissues and found that endogenous PLAC8 localizes to the apical domain of differentiated intestinal epithelium. Colon cancer cells with elevated PLAC8 levels exhibited EMT features, including increased expression of VIM and zinc finger E-box binding homeobox 1 (ZEB1), aberrant cell motility, and increased invasiveness. In contrast to classical EMT, PLAC8 overexpression reduced cell surface CDH1 and upregulated P-cadherin (CDH3) without affecting CDH2 expression. PLAC8-induced EMT was linked to increased phosphorylated ERK2 (p-ERK2), and ERK2 knockdown restored cell surface CDH1 and suppressed CDH3, VIM, and ZEB1 upregulation. In vitro, PLAC8 directly bound and inactivated the ERK2 phosphatase DUSP6, thereby increasing p-ERK2. In a murine xenograft model, knockdown of endogenous PLAC8 in colon cancer cells resulted in smaller tumors, reduced local invasion, and decreased p-ERK2. Using MultiOmyx, a multiplex immunofluorescence-based methodology, we observed coexpression of cytosolic PLAC8, CDH3, and VIM at the leading edge of a human colorectal tumor, supporting a role for PLAC8 in cancer invasion in vivo.

Organized proteomic heterogeneity in colorectal cancer liver metastases and implications for therapies

Tumor heterogeneity is a major obstacle for developing effective anticancer treatments. Recent studies have pointed to large stochastic genetic heterogeneity within cancer lesions, where no pattern seems to exist that would enable a more structured targeted therapy approach. Because to date no similar information is available at the protein (phenotype) level, we employed matrix assisted laser desorption ionization (MALDI) image-guided proteomics and explored the heterogeneity of extracellular and membrane subproteome in a unique collection of eight fresh human colorectal carcinoma (CRC) liver metastases. Monitoring the spatial distribution of over 1,000 proteins, we found unexpectedly that all liver metastasis lesions displayed a reproducible, zonally delineated pattern of functional and therapeutic biomarker heterogeneity. The peritumoral region featured elevated lipid metabolism and protein synthesis, the rim of the metastasis displayed increased cellular growth, movement, and drug metabolism, whereas the center of the lesion was characterized by elevated carbohydrate metabolism and DNA-repair activity. From the aspect of therapeutic targeting, zonal expression of known and novel biomarkers was evident, reinforcing the need to select several targets in order to achieve optimal coverage of the lesion. Finally, we highlight two novel antigens, LTBP2 and TGFBI, whose expression is a consistent feature of CRC liver metastasis. We demonstrate their in vivo antibody-based targeting and highlight their potential usefulness for clinical applications.

CONCLUSION

The proteome heterogeneity of human CRC liver metastases has a distinct, organized pattern. This particular hallmark can now be used as part of the strategy for developing rational therapies based on multiple sets of targetable antigens.

Beyond E-cadherin: roles of other cadherin superfamily members in cancer

Loss of cadherin 1 (CDH1; also known as epithelial cadherin (E-cadherin)) is used for the diagnosis and prognosis of epithelial cancers. However, it should not be ignored that the superfamily of transmembrane cadherin proteins encompasses more than 100 members in humans, including other classical cadherins, numerous protocadherins and cadherin-related proteins. Elucidation of their roles in suppression versus initiation or progression of various tumour types is a young but fascinating field of molecular cancer research. These cadherins are very diverse in both structure and function, and their mutual interactions seem to influence biological responses in complex and versatile ways.

Prognostic significance of the Wnt pathway in squamous cell laryngeal cancer

OBJECTIVES

We sought to determine the prognostic significance of the Wnt signaling pathway in operable squamous cell carcinoma of the larynx.

MATERIALS AND METHODS

In an annotated cohort of 289 operable laryngeal cancers we evaluated the prognostic impact of E-cadherin, P-cadherin and β-catenin protein expression with immunohistochemistry, as well as the mRNA expression of 7 key effectors of the Wnt pathway including secreted frizzled-related protein 4 (SFRP4), SNAI2 (SLUG) and WNT5A with qPCR (relative quantification [RQ]).

RESULTS

Using median immunoreactive scores as a pre-defined cut-off, patients whose tumors overexpressed both cytoplasmic E-cadherin and β-catenin experienced longer median OS as compared to those whose tumors overexpressed β-catenin only (median OS 124 vs. 72 months, p=0.0301) and patients whose tumors overexpressed both cytoplasmic and membranous E-cadherin experienced longer DFS as compared to those whose tumors overexpressed cytoplasmic E-cadherin only (median 118 vs. 91 months, p=0.0106). Upon hierarchical clustering of SFRP4, SNAI2 and WNT5A RQ values, profiles including co-expression of all 3 genes but also profiles with under-expression of SNAI2 and WNT5A were associated with worse outcome as compared to profiles not related to the Wnt pathway. In multivariate analysis, clustering was an independent predictor for DFS (p=0.0221) and OS (p=0.0077).

CONCLUSION

We identified gene expression profiles and IHC patterns associated with aberrant Wnt signaling conferring aggressive clinical behavior in operable squamous cell carcinoma of the larynx. Prospective validation of these results will determine whether targeting the Wnt pathway merits investigation in this disease.

The prognostic value of P-cadherin in non-muscle-invasive bladder cancer

OBJECTIVES

This research aims to specify the prognostic value of P-cadherin on recurrence and progression in non-muscle-invasive bladder cancers (NMIBC).

METHODS

A total of 110 NMIBC cases were collected and P-cadherin protein was assessed by immunohistochemical test in these samples. Correlations between P-cadherin expression and clinicopathologic features were analyzed. For recurrence-free and progression-free survival, Kaplan-Meier log-rank test was used. Then Cox univariate and multivariate analyses were further performed.

RESULTS

P-cadherin high expression correlated with tumor progression (P = 0.031). Kaplan-Meier results showed that patients with high P-cadherin expression had worse progression-free survival (P = 0.034) but not recurrence-free survival (P = 0.133) than low-expression patients. Cox regression results showed P-cadherin expression was an independent predictor for progression (P = 0.042) but not recurrence (P = 0.139) in NMIBC.

CONCLUSIONS

Our results demonstrated that P-cadherin expression correlated with tumor progression and could be taken as an independent predictor for progression in NMIBC.

Cadherins and epithelial-to-mesenchymal transition

Epithelial-mesenchymal transition (EMT) is a process whereby epithelial cells are transcriptionally reprogrammed, resulting in decreased adhesion and enhanced migration or invasion. EMT occurs during different stages of embryonic development, including gastrulation and neural crest cell delamination, and is induced by a panel of specific transcription factors. These factors comprise, among others, members of the Snail, ZEB, and Twist families, and are all known to modulate cadherin expression and, in particular, E-cadherin. By regulating expression of the cadherin family of proteins, EMT-inducing transcription factors dynamically modulate cell adhesion, allowing many developmental processes to take place. However, during cancer progression EMT can be utilized by cancer cells to contribute to malignancy. This is also reflected at the level of the cadherins, where the cadherin switch between E- and N-cadherins is a classical example seen in cancer-related EMT. In this chapter, we give a detailed overview of the entanglement between EMT-inducing transcription factors and cadherin modulation during embryonic development and cancer progression. We describe how classical cadherins such as E- and N-cadherins are regulated during EMT, as well as cadherin 7, -6B, and -11.

Research and clinical applications of molecular biomarkers in gastrointestinal carcinoma (Review)

Gastrointestinal (GI) carcinoma is a common malignant disease worldwide. Its development and progression is a multistage process involving a multifactorial etiology. Although the detailed mechanisms of the development of GI carcinoma remain controversial, the elucidation of its molecular biology over the last few years has resulted in a better perspective on its epidemiology, carcinogenesis and pathogenesis. More significantly, it is currently possible to use biological indicators or biomarkers in differential diagnosis, prognostic evaluation and specific clinical interventions. In this review, we aimed to describe the biomarkers of pathogenesis, invasion, metastasis and prognosis of GI carcinoma and discuss their potential clinical applications. The majority of these biomarkers, such as tumor-associated antigens, oncogenes and tumor suppressor genes, metastasis-associated genes, cell adhesion molecules, cytokines, growth factors and microRNAs, are currently broadly applicable.

Identification of putative immunologic targets for colon cancer prevention based on conserved gene upregulation from preinvasive to malignant lesions

The length of time required for preinvasive adenoma to progress to carcinoma, the immunogenicity of colorectal cancer (CRC), and the identification of high-risk populations make development and testing of a prophylactic vaccine for the prevention of CRC possible. We hypothesized that genes upregulated in adenoma relative to normal tissue, which maintained increased expression in CRC, would encode proteins suitable as putative targets for immunoprevention. We evaluated existing adenoma and CRC microarray datasets and identified 160 genes that were ≥2-fold upregulated in both adenoma and CRC relative to normal colon tissue. We further identified 23 genes that showed protein overexpression in colon adenoma and CRC based on literature review. Silencing the most highly upregulated genes, CDH3, CLDN1, KRT23, and MMP7, in adenoma and CRC cell lines resulted in a significant decrease in viability (P < 0.0001) and proliferation (P < 0.0001) as compared to controls and an increase in cellular apoptosis (P < 0.05 for CDH3, KRT23). Results were duplicated across cell lines representing microsatellite instability, CpG island methylator, and chromosomal instability phenotypes, suggesting immunologic elimination of cells expressing these proteins could impact the progression of all CRC phenotypes. To determine whether these proteins were immunogens, we interrogated sera from early stage CRC patients and controls and found significantly elevated CDH3 (P = 0.006), KRT23 (P = 0.0007), and MMP7 (P < 0.0001) serum immunoglobulin G in cases as compared to controls. These data show a high throughput approach to the identification of biologically relevant putative immunologic targets for CRC and identified three candidates suitable for vaccine development.

β-catenin overexpression in the nucleus predicts progress disease and unfavourable survival in colorectal cancer: a meta-analysis

BACKGROUND

β-catenin plays a key role in the progression of colorectal cancer (CRC). However, its prognostic significance for patients with CRC remains controversial.

METHODOLOGY

Identical search strategies were used to search relevant literatures in the PubMed, Embase and Web of Science databases. The correlation between β-catenin expression and clinicopathological features and prognosis was analyzed.

PRINCIPAL FINDINGS

A total of 18 studies met the inclusion criteria, which comprised 3665 cases. Meta-analysis suggested that β-catenin overexpression in the nucleus was significantly associated with disease free survival (DFS) (n = 541 in 3 studies; HR = 1.87, 95% CI: 1.28-2.71; Z = 3.26; P = 0.001) and overall survival (OS) for CRC patients (n = 2630 in 10 studies; HR = 1.55, 95% CI: 1.12-2.14; Z = 2.62; P = 0.009). However, there was no significant association between β-catenin expression in the cytoplasm and OS (n = 1327 in 3 studies; HR = 1.04, 95% CI: 0.88-1.24, Z = 0.46, P = 0.643). The combined odds ratio (OR) of β-catenin in the nucleus indicated that β-catenin overexpression was associated with advanced stage CRC (n = 950 in 7 studies; OR = 0.71, 95% CI: 0.53-0.94; Z = 2.35; P = 0.019) and metastasis of CRC (n = 628 in 5 studies; OR = 0.49, 95% CI: 0.25-0.96, Z = 2.06, P = 0.039). β-catenin overexpression in the nucleus had no correlation with the tumor site (colon or rectum), differentiation grade, lymph node status or depth of invasion. The pooled ORs were 1.09 (95% CI: 0.41-2.91, Z = 0.18, P = 0.856), 1.27(95% CI: 0.76-2.10, Z = 0.92, P = 0.357), 0.71(95% CI: 0.46-1.09, Z = 1.58, P = 0.115) and 0.82(95% CI: 0.4-1.68, Z = 0.53, P = 0.594).

CONCLUSIONS

This study showed that β-catenin overexpression in the nucleus, rather than in the cytoplasm, appeared to be associated with progress disease and a worse prognosis for CRC patients.

Expression of smoothened protein in colon cancer and its prognostic value for postoperative liver metastasis

BACKGROUDS: The hedgehog (Hh) signaling pathway is composed of patched (PTCH) and smoothened (SMO), two transmembrane proteins, and downstream glioma-associated oncogene homolog (Gli) transcription factors. Hh signaling plays a pathological role in the occurrence and development of various cancers.

METHODS

To investigate the expression of SMO protein in colon cancer and its association with clinicopathological parameters and postoperative liver metastasis, immunohistochemistry was performed with paraffin-embedded specimens of 96 cases. Relationships between SMO protein expression and clinicopathological parameters, postoperative liver metastasis were analyzed.

RESULTS

IHC examination showed that SMO protein expression was significantly increased in colon cancer tissues compared to normal colon tissues (P = 0.042), positively related to lymph node metastases (P = 0.018) and higher T stages (P = 0.026). Postoperative live metastasis-free survival was significantly longer in the low SMO expression group than in those with high SMO expression (48.7 ± 8.02 months vs 28.0 ± 6.86 months, P=0.036). Multivariate analysis showed SMO expression level to be an independent prognostic factor for postoperative live metastasis-free survival (95% confidence interval [CI] =1.46-2.82, P = 0.008).

CONCLUSIONS

Our results suggest that in patients with colon cancer, the SMO expression level is an independent biomarker for postoperative liver metastasis, and SMO might play an important role in colon cancer progression.

Overexpression of miR-92a correlates with tumor metastasis and poor prognosis in patients with colorectal cancer

OBJECTIVES

MicroRNAs regulate gene expression at the post-transcriptional level and play important roles in cancer development, progression, and metastasis. The aim of this study was to investigate the expression of miR-92a in colorectal cancer and the normal adjacent mucosa and its potential relevance to clinicopathological characteristics and patient survival.

METHODS

Surgical specimens of cancer tissue and adjacent normal mucosa were obtained from 82 patients with colorectal carcinomas. The relative expression levels of miR-92a mRNA in the cancer and the normal adjacent mucosa were measured by quantitative real-time reverse transcriptase polymerase chain reaction. We analyzed their correlation with tumor metastasis, clinicopathologic parameters, and clinical outcome.

RESULTS

The relative expression levels of miR-92a were significantly higher in colorectal cancer tissues than in the normal adjacent mucosa (p < 0.001), and a high expression of miR-92a correlated with advanced clinical stage (p = 0.025), lymph node metastases (p = 0.015), and distant metastases (p = 0.046). Kaplan-Meier analysis indicated that patients with high miR-92a expression had a poor overall survival (p = 0.001). Moreover, multivariate analysis showed that increased expression of miR-92a was an independent predictor of overall survival.

CONCLUSION

This study revealed that miR-92a overexpression was correlated with specific colorectal cancer biopathologic features, such as TNM stage, lymph node and distant metastases, and poor survival of the patients, indicating that miR-92a may serve as a molecular prognostic marker for colorectal cancer and disease progression.