Towards understanding the mechanisms of actions of carcinoembryonic antigen-related cell adhesion molecule 6 in cancer progression

Re-expression of REG family and DUOXs genes in CRC organoids by co-culturing with CAFs

Organoids derived from epithelial tumors have recently been utilized as a preclinical model in basic and translational studies. This model is considered to represent the original tumor in terms of 3D structure, genetic and cellular heterogeneity, but not tumor microenvironment. In this study, we established organoids and paired cancer-associated fibroblasts (CAFs) from surgical specimens of colorectal carcinomas (CRCs), and evaluated gene expression profiles in organoids with and without co-culture with CAFs to assess interactions between tumor cells and CAFs in tumor tissues. We found that the expression levels of several genes, which are highly expressed in original CRC tissues, were downregulated in organoids but re-expressed in organoids by co-culturing with CAFs. They comprised immune response- and external stimulus-related genes, e.g., REG family and dual oxidases (DUOXs), which are known to have malignant functions, leading tumor cells to proliferative and/or anti-apoptotic states and drug resistant phenotypes. In addition, the degree of differential induction of REG1 and DUOX2 in the co-culture system varied depending on CAFs from each CRC case. In conclusion, the co-culture system of CRC organoids with paired CAFs was able to partially reproduce the tumor microenvironment.

Colorectal Cancer Stem Cells in the Progression to Liver Metastasis

Colorectal carcinoma (CRC) is a leading cause of cancer mortality. Tumorigenesis is a dynamic process wherein cancer stem cells (CSCs) and their microenvironment promote initiation, progression, and metastasis. Metastatic colonization is an inefficient process that is very complex and is poorly understood; however, in most cases, metastatic disease is not curable, and resistance mechanisms tend to develop against conventional treatments. An understanding of the underlying mechanisms and factors that contribute to the development of metastasis in CRC can aid in the search for specific therapeutic targets for improving standard treatments. In this review, we summarize current knowledge regarding tumor biology and the use of stroma cells as prognostic factors and inflammatory inducers associated with the use of tumor microenvironments as a promoter of cancer metastasis. Moreover, we look into the importance of CSC, pericytes, and circulating tumor cells as mechanisms that lead to liver metastasis, and we also focus on the cellular and molecular pathways that modulate and regulate epithelial–mesenchymal transition. Finally, we discuss a novel therapeutic target that can potentially eliminate CSCs as a CRC treatment.

Biological Functions and Identification of Novel Biomarker Expressed on the Surface of Breast Cancer-Derived Cancer Stem Cells via Proteomic Analysis

Breast cancer is one of the most common life-threatening malignancies and the top cause of cancer deaths in women. Although many conventional therapies exist for its treatment, breast cancer still has many handicaps to overcome. Cancer stem cells (CSCs) are a well-known cause of tumor recurrences due to the ability of CSCs for self-renewal and differentiation into cell subpopulations, similar to stem cells. To fully treat breast cancer, a strategy for the treatment of both cancer cells and CSCs is required. However, current strategies for the eradication of CSCs are non-specific and have low efficacy. Therefore, surface biomarkers to selectively treat CSCs need to be developed. Here, 34 out of 641 surface biomarkers on CSCs were identified by proteomic analysis between the human breast adenocarcinoma cell line MCF-7 and MCF-7-derived CSCs. Among them, carcinoembryonic antigen-related cell adhesion molecules 6 (CEACAM6 or CD66c), a member of the CEA family, was selected as a novel biomarker on the CSC surface. This biomarker was then experimentally validated and evaluated for use as a CSC-specific marker. Its biological effects were assessed by treating breast cancer stem cells (BCSCs) with short hairpin (sh)-RNA under oxidative cellular conditions. This study is the first to evaluate the biological function of CD66c as a novel biomarker on the surface of CSCs. This marker is available as a moiety for use in the development of targeted therapeutic agents against CSCs.

Microtube Array Membrane (MTAM)-Based Encapsulated Cell Therapy for Cancer Treatment

The treatment of cancer has evolved significantly in recent years with a strong focus on immunotherapy. Encapsulated Cell Therapy (ECT) for immunotherapy-based anti-cancer treatment is a unique niche within this landscape, where molecules such as signaling factors and antibodies produced from cells are encapsulated within a vehicle, with a host amount of benefits in terms of treatment efficacy and reduced side effects. However, traditional ECTs generally lie in two extremes; either a macro scale vehicle is utilized, resulting in a retrievable system but with limited diffusion and surface area, or a micro scale vehicle is utilized, resulting in a system that has excellent diffusion and surface area but is unretrievable in the event of side effects occurring, which greatly compromises the biosafety of patients. In this study we adapted our patented and novel electrospun Polysulfone (PSF) Microtube Array Membranes (MTAMs) as a 'middle' approach to the above dilemma, which possess excellent diffusion and surface area while being retrievable. Hybridoma cells were encapsulated within the PSF MTAMs, where they produced CEACAM6 antibodies to be used in the suppression of cancer cell line A549, MDA-MB-468 and PC 3 (control). In vitro and in vivo studies revealed excellent cell viability of hybridoma cells with continuous secretion of CEACAM6 antibodies which suppressed the MDA-MB-468 throughout the entire 21 days of experiment. Such outcome suggested that the PSF MTAMs were not only an excellent three-dimensional (3D) cell culture substrate but potentially also an excellent vehicle for the application in ECT systems. Future research needs to include a long term in vivo >6 months study before it can be used in clinical applications.

Comparing blood versus tissue-based biomarkers expression in breast cancer patients

Molecular markers have been used as a tool for diagnostic approaches, staging, and evaluation of therapeutic responses in patients with cancer. Cancer molecular markers can also help clinicians to make decision on therapy and prognosis evaluation at the time of diagnosis. In the early diagnosis of breast cancer (BC), estrogen and progesterone receptors (ER/PR) expression levels should be determined through immunohistochemistry (IHC). In molecular genetics, there are some important tissue-based markers that can also be found in blood, such as Mammaglobin (MAM), Cytokeratin 19 (CK19), Mucin (MUC), Proto-oncogene (c-Myc), antigen Ki-67 (Ki67), and Carcinoembryonic antigen (CEA). In this study, the positive level of the marker genes in both blood and tissue of the BC patients were compared using reverse transcription polymerase chain reaction (RT-PCR) method. In addition, the importance of blood vs. tissue-based markers in BC diagnosis also demonstrated and is discussed. CEA (O), ERβ, CK19 and, c-Myc molecular markers were significantly different between blood of normal and patients while there was no significant difference of these markers in tissue samples. Blood-based biomarkers can be used for the early diagnosis of BC. Comparing blood versus tissue-based biomarkers indicated that there are correlations between markers in blood and tissue, since blood markers can be substitute to tissue markers in BC patients in the future.

In situ amplified QCM immunoassay for carcinoembryonic antigen with colorectal cancer using horseradish peroxidase nanospheres and enzymatic biocatalytic precipitation

An innovative quartz crystal microbalance immunoassay was designed for detection of carcinoembryonic antigen using horseradish peroxidasenanoparticle as the enhancer, accompanying enzymatic biocatalytic precipitation toward 4-chloro-1-naphthol.

Gene Therapy for Liver Cancers: Current Status from Basic to Clinics

The liver is a key organ for metabolism, protein synthesis, detoxification, and endocrine function, and among liver diseases, including hepatitis, cirrhosis, malignant tumors, and congenital disease, liver cancer is one of the leading causes of cancer-related deaths worldwide. Conventional therapeutic options such as embolization and chemotherapy are not effective against advanced-stage liver cancer; therefore, continuous efforts focus on the development of novel therapeutic options, including molecular targeted agents and gene therapy. In this review, we will summarize the progress toward the development of gene therapies for liver cancer, with an emphasis on recent clinical trials and preclinical studies.

ZnS/C/MoS2 Nanocomposite Derived from Metal-Organic Framework for High-Performance Photo-Electrochemical Immunosensing of Carcinoembryonic Antigen

A hexafluorophosphate ionic liquid is used as a functional monomer to prepare a metal-organic framework (Zn-MOF). Zn-MOF is used as a template for MoS₂ nanosheets synthesis and further carbonized to yield light-responsive ZnS/C/MoS₂ nanocomposites. Zn-MOF, carbonized-Zn-MOF, and ZnS/C/MoS₂ nanocomposites are characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, X-ray diffraction pattern, scanning electron microscopy (SEM), element mapping, Raman spectroscopy, X-ray photoelectron spectroscopy, fluorescence, and nitrogen-adsorption analysis. Carcinoembryonic antigen (CEA) is selected as a model to construct an immunosensing platform to evaluate the photo-electrochemical (PEC) performances of ZnS/C/MoS₂ nanocomposites. A sandwich-type PEC immunosensor is fabricated by immobilizing CEA antibody (Ab₁ ) onto the ZnS/C/MoS₂ /GCE surface, subsequently binding CEA and the alkaline phosphatase-gold nanoparticle labeled CEA antibody (ALP-Au-Ab₂ ). The catalytic conversion of vitamin C magnesium phosphate produces ascorbic acid (AA). Upon being illuminated, AA can react with photogenerated holes from ZnS/C/MoS₂ nanocomposites to generate a photocurrent for quantitative assay. Under optimized experimental conditions, the PEC immunosensor exhibits excellent analytical characteristics with a linear range from 2.0 pg mL^-1 to 10.0 ng mL^-1 and a detection limit of 1.30 pg mL^-1 (S/N = 3). The outstanding practicability of this PEC immunosensor is demonstrated by accurate assaying of CEA in clinical serum samples.

Serum Expression of β-Catenin Is a Potential Detection Marker in Patients with Colorectal Cancer

Object

To investigate the correlation between the level of serum β-catenin and the disease progression of colorectal polyp (CRP) and colorectal cancer (CRC) and find its potential diagnostic value.

Methods

A total of 327 clinical serum samples and their electronic medical records were collected. Detecting by enzyme-linked immunosorbent assay (ELISA), the correlations of serum β-catenin with tumor marker carcinoembryonic antigen (CEA) and CRC clinicopathological parameters and the receiver operating characteristic (ROC) curve were analyzed.

Results

Serum β-catenin levels in the CRP and CRC patients were significantly higher than those in the healthy control (HC) group (P < 0.05 and P < 0.001). Compared with CRP, serum β-catenin level in CRC was also increased (P < 0.05). However, there was no significant difference in gender, age, location, tumor size, Dukes staging, or metastasis (P > 0.05) between serum β-catenin and clinical parameters of CRC. There was no correlation between serum β-catenin levels and CEA in CRC patients (P = 0.14). ROC curve analysis showed that serum β-catenin possessed the maximum diagnostic efficiency in CRP (AUC = 0.73, P < 0.05) with 86.41% sensitivity and 51.56% specificity. β-Catenin combined with CEA had the highest diagnostic efficiency (AUC = 0.88, P < 0.05) with 81.88% sensitivity and 73.44% specificity. With CRC patients from CRP patients, ROC analysis of the combining detection (AUC = 0.70, P < 0.05) had the 70% sensitivity and 84.5% specificity.

Conclusion

The serum β-catenin levels are gradually increased in CRP and CRC, while there is no correlation between its levels and CRC disease process. Single serum β-catenin or combined CEA would be one of the potential candidate biomarkers for colorectal disease diagnosis.

A qualitative transcriptional signature for determining the grade of colorectal adenocarcinoma

Histological grading (HG) is an important prognostic factor of colorectal adenocarcinoma (CRAC): the high-grade CRAC patients have poorer prognosis after tumor resection. Especially, the high-grade stage II CRAC patients are recommended to receive adjuvant chemotherapy. Due to the subjective nature of HG assessment, it is difficult to achieve consistency among pathologists, which brings patients uncertain grading outcomes and inappropriate treatments. We developed a qualitative transcriptional signature based on the within-sample relative expression orderings (REOs) of gene pairs to discriminate high-grade and low-grade CRAC. Using the stage II-III CRAC samples, we detected gene pairs with stable REOs in the high-grade samples and reversal stable REOs in the low-grade samples, and retained the gene pairs whose specific REO patterns were significantly associated with the disease-free survival of patients by univariate Cox regression model. Then, we used a forward-backward searching procedure to extract gene pairs with the highest concordance index as the final grading signature. Finally, 9 gene pairs (9-GPS) were developed to divide CRAC patients into high-grade and low-grade groups. With the signature, there were more differential expression characteristics between reclassified high-grade and low-grade groups. Significant difference of prognosis between the classified two group patients could be seen in four independent datasets. Additionally, genomic analyses showed that the classified high-grade groups were characterized by hypermutation while classified low-grade groups were characterized by frequent copy number alternations. In conclusion, the 9-GPS can provide an objective and robust grading assessment for CRAC patients, which could assist clinical treatment decision.

Carcinoembryonic antigen related cell adhesion molecule 6 promotes the proliferation and migration of renal cancer cells through the ERK/AKT signaling pathway

Background

Carcinoembryonic antigen related cell adhesion molecule 6 (CEACAM6) is a versatile glycoprotein and a member of the CEACAM family. Studies suggested that it served as a diagnostic and prognostic biomarker in some malignancies. In addition, it is involved in tumorigenesis by stimulating proliferation, suppressing apoptosis, facilitating migration and invasion, promoting angiogenesis, and inducing drug resistance. In the present study, we demonstrated the oncogenic effects of CEACAM6 in clear cell renal cell carcinoma (ccRCC).

Methods

CEACAM6 expression was detected by quantitative real-time PCR (qRT-PCR), immunohistochemical staining and western blot in ccRCC tumor tissues and cell lines. Survival analysis was performed using the data of TCGA database. Cell proliferation and migration were detected by CCK-8 and transwell assays with the overexpression or silencing of CEACAM6. LY294002 was used to block the activation of PI3K/AKT pathway. Associated pathway proteins were detected by western blot.

Results

CEACAM6 was upregulated in ccRCC cell lines and tumor tissues. Longer overall survival was observed in patients with relatively low CEACAM6 levels. Furthermore, overexpression of CEACAM6 promoted the proliferation and migration of ccRCC cells. Conversely, shRNA-mediated CEACAM6 depletion modulated those changes. Further investigation demonstrated that the ERK/AKT signaling pathway activation played a pivotal role. In addition, PI3K/AKT pathway blockade abrogated the effects of CEACAM6 overexpression.

Conclusions

Aberrantly high expression of CEACAM6 is a stimulus for the formation and progression of ccRCC.

Sandwich-type electrochemical immunosensor constructed using three-dimensional lamellar stacked CoS2@C hollow nanotubes prepared by template-free method to detect carcinoembryonic antigen

Effective treatment of cancer depends on early detection of tumor markers. In this paper, an effective template-free method was used to prepare CoS₂@C three-dimensional hollow sheet nanotubes as the matrix of the immunosensor. The unique three-dimensional hybrid hollow tubular nanostructure provides greater contact area and enhanced detection limit. The CoS₂@C-NH₂-HRP nanomaterial was synthesized as a marker and had a high specific surface area, which can effectively improve the electrocatalytic ability of hydrogen peroxide (H₂O₂) reduction while increasing the amount of capture-fixed carcinoembryonic antigen antibody (anti-CEA). In addition, the co-bonded horseradish peroxidase (HRP) can further promote the redox of H₂O₂ and amplify the electrical signal. Carcinoembryonic antigen (CEA) was quantified by immediate current response (i-t), and the prepared immunosensor had good analytical performance under optimized conditions. The current signal and the concentration of CEA were linear in the range of 0.001-80 ng/mL, and the detection limit was 0.33 pg/mL (S/N = 3). The designed immunosensor has good selectivity, repeatability and stability, and the detection of human serum samples shows good performance. Furthermore, electrochemical immunosensor has broad application prospects in the clinical diagnosis of CEA.

The role of liver microenvironment in hepatic metastasis

Metastasis is still poorly understood and thus further research must be conducted to provide insight into the driving factors. Novel research has revealed the significance of the microenvironment in the delegation of metastasis, expanding the field of cancer metastasis to cells and cell environments surrounding the migrated tumor cells. Research on hepatic metastasis is an ever-growing domain of this field, as several primary tumors can metastasize to the liver. The two features within the liver that promote metastasis—cellular and acellular—are found in the current interpretation of liver microenvironment. Novel findings of both are included in this review. Different hypotheses detailing the methods by which metastasis can occur must be included to understand the significance of the microenvironment, as well as a brief overview of the methods that can be used during research. This review aims to highlight the importance of liver microenvironment on the development or potential regression of hepatic metastasis through discussing both acellular and cellular components of liver microenvironment and their interaction with metastasis.

Co-expression Network Analysis Elucidated a Core Module in Association With Prognosis of Non-functioning Non-invasive Human Pituitary Adenoma

Non-functioning pituitary adenomas (NFPAs) are tumors with clinically challenging features since they have insidious progression. A complex network of gene interactions is thought to have roles in tumor formation and progression. Therefore, revealing the genetic network behind NFPA tumorigenesis is not only essential to attain further knowledge of tumor biology, but also plays a fundamental role in the development of efficacious treatment strategies. Differential co-expression network analysis is an outstanding approach for elucidation of groups of genes which show distinct co-expression patterns among phenotypes. In this study, we carried out a differential co-expression network analysis of NFPA-associated transcriptome dataset (n = 40) considering invasive (n = 22) and non-invasive (n = 18) phenotypes. Furthermore, we identified differentially co-expressed and co-regulated mRNA modules, which might be considered as potential systems biomarkers for NFPA prognosis and invasiveness. As a result, we have identified a novel 13-gene module, including CEACAM6, CYP4B1, EIF2S2, HID1, IFFO1, MYO18A, PDCD2, SGIP1, SWSAP1, and four unknown genes (A_24_P127621, A_24_P255786, A_24_P683553, and A_24_P916979), which was able to categorize the patients into two groups as invasive and non-invasive NFPA with distinct prognosis. The prognostic core module genes were associated with progression and prognosis of brain and glandular based cancers as well. Furthermore, these module genes were also expressed in blood, salivary gland, and spinal cord tissues. These results may provide the evidence on featured gene module which might play a prominent role in NFPA prognosis and sub-typing as effective biomarkers and therapeutic targets in the future.

Evidence for an oncogenic role of HOXC6 in human non-small cell lung cancer

Background

Identification of specific biomarkers is important for the diagnosis and treatment of non-small cell lung cancer (NSCLC). HOXC6 is a homeodomain-containing transcription factor that is highly expressed in several human cancers; however, its role in NSCLC remains unknown.

Methods

The expression and protein levels of HOXC6 were assessed in NSCLC tissue samples by Quantitative real-time PCR (qRT-PCR) and immunohistochemistry, respectively. HOXC6 was transfected into the NSCLC cell lines A549 and PC9, and used to investigate its effect on proliferation, migration, and invasion using CFSE, wound healing, and Matrigel invasion assays. Next-generation sequencing was also used to identify downstream targets of HOXC6 and to gain insights into the molecular mechanisms underlying its biological function.

Results

HOXC6 expression was significantly increased in 66.6% (20/30) of NSCLC tumor samples in comparison to normal controls. HOXC6 promoted proliferation, migration, and invasion of NSCLC cells in vitro. RNA-seq analysis demonstrated the upregulation of 310 and 112 genes in A549-HOXC6 and PC9-HOXC6 cells, respectively, and the downregulation of 665 and 385 genes in A549-HOXC6 and PC9-HOXC6 cells, respectively. HOXC6 was also found to regulate the expression of genes such as CEACAM6, SPARC, WNT6, CST1, MMP2, and KRT13, which have documented pro-tumorigenic functions.

Discussion

HOXC6 is highly expressed in NSCLC, and it may enhance lung cancer progression by regulating the expression of pro-tumorigenic genes involved in proliferation, migration, and invasion. Our study highlighted the oncogenic potential of HOXC6, and suggests that it may be a novel biomarker for the diagnosis and treatment of NSCLC.

Expression of Chosen Carcinoembryonic-Related Cell Adhesion Molecules in Pancreatic Intraepithelial Neoplasia (PanIN) Associated with Chronic Pancreatitis and Pancreatic Ductal Adenocarcinoma (PDAC)

Aims: Carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) are members of the glycosylphosphatidylinositol (GPI)-linked immunoglobulin (Ig) superfamily and take part in regulation of cell adhesion, tumor suppression and angiogenesis. Overexpression of CEACAM 1, 5 and 6 is widely described in several gastrointestinal epithelial tumors. The aim of study was to evaluate the expression of CEACAM 1, CEACAM 5 and CEACAM 6 in the most common precursor lesions of pancreatic ductal adenocarcinoma -pancreatic intraepithelial neoplasia (PanIN). Methods and results: The study group consisted of 32 patients treated for chronic pancreatitis and 38 patients with pancreatic ductal adenocarcinoma who also had pancreatic intraepithelial neoplasia. The expression of CEACAM was performed by immunohistochemical method and evaluated using 3-point scale: 0 - lack of positive reaction in pancreatic intraepithelial neoplasia, 1 (weak and moderate) - reaction present in 1-30% epithelial cells in PanIN and 2 (strong) - reaction present in >30% epithelial cells in PanIN. Expression of CEACAM 1, 5 and 6 increased with increasing degree of advancement of PanIN. Differences in expression of CEACAM 1, 5 and 6 between normal pancreatic ducts and different degrees of PanIN were statistically significant (p<0.001). We observed relationship between CEACAM1 expression and localization of PanIN in different parts of the pancreas. Conclusions: CEACAM 1, CEACAM 5 and CEACAM 6 expression appears to be an early event in pancreatic carcinogenesis. Moreover, expression of CEACAM 1, 5 and 6 may represent a useful biomarker that may aid in the identification of precancerous lesions in the pancreas.

Facile generation of antibody heavy and light chain diversities for yeast surface display by Golden Gate Cloning

Antibodies can be successfully engineered and isolated by yeast or phage display of combinatorial libraries. Still, generation of libraries comprising heavy chain as well as light chain diversities is a cumbersome process involving multiple steps. Within this study, we set out to compare the output of yeast display screening of antibody Fab libraries from immunized rodents that were generated by Golden Gate Cloning (GGC) with the conventional three-step method of individual heavy- and light-chain sub-library construction followed by chain combination via yeast mating (YM). We demonstrate that the GGC-based one-step process delivers libraries and antibodies from heavy- and light-chain diversities with similar quality to the traditional method while being significantly less complex and faster. Additionally, we show that this method can also be used to successfully screen and isolate chimeric chicken/human antibodies following avian immunization.

Towards understanding the mechanisms of actions of carcinoembryonic antigen-related cell adhesion molecule 6 in cancer progression

Human carcinoembryonic antigen (CEA) is the prototypic member of a family of highly related cell surface glycoproteins that includes carcinoembryonic antigen‐related cell adhesion molecule 6 (CEACAM6) and others. CEACAM6 (formerly NCA), which belongs to the immunoglobulin superfamily, is a cell adhesion protein of the CEA family. It is normally expressed on the epithelial surfaces and on the surface of myeloid cells (CD66c). CEACAM6 is a multi‐functional glycoprotein that mediates homotypic binding with other CEA family members and heterotypic binding with integrin receptors. It functions by organizing tissue architecture and regulating different signal transduction, while aberrant expression leads to the development of human malignancies. It was first discovered in proliferating cells of adenomas and hyperplastic polyps in comparison to benign colonic tissue when overexpressed on the surface of various cell types in model systems. CEACAM6 functions as a pan‐inhibitor of cell differentiation and cell polarization, and it also causes distortion of tissue architecture. Moreover, overexpression of CEACAM6 modulates cancer progression through aberrant cell differentiation, anti‐apoptosis, cell growth and resistance to therapeutic agents. In addition, CEACAM6 overexpression in multiple malignancies promotes cell invasion and metastasis, thereby representing an acquired advantage of tumor cells directly responsible for an invasive phenotype. This review focuses on the findings supporting the mechanisms of actions linking the oncogenic potential of CEACAM6 to the onset of cancer progression and pathogenesis, especially in breast cancer, and to validating CEACAM6 as a target to pave the way towards the design of efficient therapeutic strategies against breast cancer.