Carcinoembryonic antigen-stimulated THP-1 macrophages activate endothelial cells and increase cell–cell adhesion of colorectal cancer cells

Machine learning for predicting liver and/or lung metastasis in colorectal cancer: A retrospective study based on the SEER database

OBJECTIVE

This study aims to establish a machine learning (ML) model for predicting the risk of liver and/or lung metastasis in colorectal cancer (CRC).

METHODS

Using the National Institutes of Health (NIH)'s Surveillance, Epidemiology, and End Results (SEER) database, a total of 51265 patients with pathological diagnosis of colorectal cancer from 2010 to 2015 were extracted for model development. On this basis, We have established 7 machine learning algorithm models. Evaluate the model based on accuracy, and AUC of receiver operating characteristics (ROC) and explain the relationship between clinical pathological features and target variables based on the best model. We validated the model among 196 colorectal cancer patients in Beijing Electric Power Hospital of Capital Medical University of China to evaluate its performance and universality. Finally, we have developed a network-based calculator using the best model to predict the risk of liver and/or lung metastasis in colorectal cancer patients.

RESULTS

51265 patients were enrolled in the study, of which 7864 (15.3 %) had distant liver and/or lung metastasis. RF had the best predictive ability, In the internal test set, with an accuracy of 0.895, AUC of 0.956, and AUPR of 0.896. In addition, the RF model was evaluated in the external validation set with an accuracy of 0.913, AUC of 0.912, and AUPR of 0.611.

CONCLUSION

In this study, we constructed an RF algorithm mode to predict the risk of colorectal liver and/or lung metastasis, to assist doctors in making clinical decisions.

Combined effect of serum carcinoembryonic antigen and hepatic steatosis on new-onset ischemic heart disease among middle-aged and older Korean adults: a cohort study

Background

Carcinoembryonic antigen (CEA) is a commonly used tumor marker in cancer screening. However, it has also been associated with metabolic alterations. Hepatic steatosis, the accumulation of fat in liver cells, is associated with various cardiovascular risk factors. This study investigated the risk of ischemic heart disease (IHD) in individuals with elevated CEA levels, hepatic steatosis, and their co-occurrence.

Methods

The study cohort comprised 5,580 Korean adults who underwent health examinations between November 2006 and June 2010. Data regarding baseline CEA levels, hepatic steatosis status, and development of IHD were collected. Hepatic steatosis was defined as more than two findings: deep attenuation, vascular blurring, and increased liver echogenicity on abdominal ultrasound. Participants were divided into four groups based on their CEA and hepatic steatosis status: no hepatic steatosis and low CEA (group 1), no hepatic steatosis and elevated CEA (group 2), low CEA and hepatic steatosis (group 3), and elevated CEA and hepatic steatosis (group 4).

Results

A total of 226 (4.1%) participants developed IHD during the follow-up period. Participants with elevated CEA levels and hepatic steatosis (group 4) had the highest cumulative incidence of IHD in comparison to other groups (p < 0.001). The combined effect of elevated CEA levels and hepatic steatosis showed significantly greater area under the receiver operating characteristic curve than hepatic steatosis alone (p < 0.001). Furthermore, participants with elevated CEA and hepatic steatosis (group 4) had higher risk of developing IHD compared to those with low CEA and no hepatic steatosis (group 1) (hazard ratio: 1.63, 95% confidence interval: 1.04-2.55, p = 0.034).

Conclusion

Co-occurrence of elevated CEA levels and hepatic steatosis increases the risk of IHD. Comprehensive risk assessment is crucial to guide interventions and improve cardiovascular health in individuals with both the conditions.

Cancer-Associated Fibroblast Heterogeneity and Its Influence on the Extracellular Matrix and the Tumor Microenvironment

The tumor microenvironment comprises multiple cell types, like cancer cells, endothelial cells, fibroblasts, and immune cells. In recent years, there have been massive research efforts focusing not only on cancer cells, but also on other cell types of the tumor microenvironment, thereby aiming to expand and determine novel treatment options. Fibroblasts represent a heterogenous cell family consisting of numerous subtypes, which can alter immune cell fractions, facilitate or inhibit tumor growth, build pre-metastatic niches, or stabilize vessels. These effects can be achieved through cell-cell interactions, which form the extracellular matrix, or via the secretion of cytokines or chemokines. The pro- or antitumorigenic fibroblast phenotypes show variability not only among different cancer entities, but also among intraindividual sites, including primary tumors or metastatic lesions. Commonly prescribed for arterial hypertension, the inhibitors of the renin-angiotensin system have recently been described as having an inhibitory effect on fibroblasts. This inhibition leads to modified immune cell fractions and increased tissue stiffness, thereby contributing to overcoming therapy resistance and ultimately inhibiting tumor growth. However, it is important to note that the inhibition of fibroblasts can also have the opposite effect, potentially resulting in increased tumor growth. We aim to summarize the latest state of research regarding fibroblast heterogeneity and its intricate impact on the tumor microenvironment and extracellular matrix. Specifically, we focus on highlighting recent advancements in the comprehension of intraindividual heterogeneity and therapy options within this context.

The impact of macrophages on endothelial cells is potentiated by cycling hypoxia: Enhanced tumor inflammation and metastasis

Cycling hypoxia (cyH), neo-angiogenesis, and tumor-associated macrophages are key features of the tumor microenvironment. In this study, we demonstrate that cyH potentiates the induction by unpolarized and M1-like macrophages of endothelial inflammatory phenotype and adhesiveness for monocytes and cancer cells. This process triggers a positive feedback loop sustaining tumor inflammation. This work opens the door for innovative therapeutic strategies to treat tumor inflammation and metastasis.

In cancers, the interaction between macrophages and endothelial cells (ECs) regulates tumor inflammation and metastasis. These cells are both affected by cycling hypoxia (cyH), also called intermittent hypoxia, a feature of the tumor microenvironment. cyH is also known to favor tumor inflammation and metastasis. Nonetheless, the potential impact of cyH on the dialog between macrophages and ECs is still unknown. In this work, the effects of unpolarized, M1-like, and M2-like macrophages exposed to normoxia, chronic hypoxia (chH), and cyH on endothelial adhesion molecule expression, pro-inflammatory gene expression, and EC adhesiveness for monocytes and cancer cells were investigated. cyH increased the ability of unpolarized and M1-like macrophages to induce EC inflammation and to increase the expression of the EC endothelial adhesion molecule ICAM1, respectively. Unpolarized, M1-like, and M2-like macrophages were all able to promote EC adhesive properties toward cancer cells. Furthermore, the ability of macrophages (mostly M1-like) to shift EC phenotype toward one allowing cancer cell and monocyte adhesion onto ECs was potentiated by cyH. These effects were specific to cyH because they were not observed with chH. Together, these results show that cyH amplifies the effects of macrophages on ECs, which may promote tumor inflammation and metastasis.

Increased Carcinoembryonic Antigen (CEA) Level Is Highly Associated with Low Skeletal Muscle Mass in Asymptomatic Adults: A Population-Based Study

We investigated the relationship between high carcinoembryonic antigen (CEA) levels and low skeletal muscle mass (LMM) in asymptomatic adults in a population-based study. A total of 202,602 adults (mean age 41.7 years) without malignancy, stroke, cardiovascular disease, or chronic lung/liver disease were included. A high CEA level was defined as ≥5 ng/mL. Skeletal muscle mass index (SMI) was calculated based on appendicular muscle mass (kg)/height (m)2. Participants were classified into three groups based on SMI: “normal”, “mild LMM”, and “severe LMM.” The prevalence of elevated CEA levels was the highest in subjects with severe LMM (4.2%), followed by those with mild LMM (1.6%) and normal muscle mass (1.1%) (p for trend < 0.001). In multivariate logistic regression analysis, high CEA was independently associated with having mild LMM (adjusted odds ratio, 1.139 [95% confidence interval, 1.092−1.188]) and severe LMM (2.611 [2.055−3.319]) compared to normal muscle mass. Furthermore, the association between high CEA and severe LMM was stronger in women than that in men (women, 5.373 [2.705−10.669]; men, 2.273 [1.762−2.933]). Elevated CEA levels were significantly associated with a higher prevalence of LMM. Therefore, increased CEA could be used as a biomarker for detecting LMM in adults without cancer.

Identification of Cell Surface Molecules That Determine the Macrophage Activation Threshold Associated With an Early Stage of Malignant Transformation

The ability of immune cells to sense changes associated with malignant transformation as early as possible is likely to be important for the successful outcome of cancer immunosurveillance. In this process, the immune system faces a trade-off between elimination of cells harboring premalignant or malignant changes, and autoimmune pathologies. We hypothesized that the immune system has therefore evolved a threshold for the stage of transformation from normal to fully malignant cells that first provides a threat (danger) signal requiring a response. We co-cultured human macrophages with a unique set of genetically related human cell lines that recapitulate successive stages in breast cancer development: MCF10A (immortalized, normal); MCFNeoT (benign hyperplasia); MCFT1 (atypical hyperplasia); MCFCA1 (invasive cancer). Using cytokines-based assays, we found that macrophages were inert towards MCF10A and MCFNeoT but were strongly activated by MCFT1 and MCFCA1 to produce inflammatory cytokines, placing the threshold for recognition between two premalignant stages, the earlier stage MCFNeoT and the more advanced MCFT1. The cytokine activation threshold paralleled the threshold for enhanced phagocytosis. Using proteomic and transcriptomic approaches, we identified surface molecules, some of which are well-known tumor-associated antigens, that were absent or expressed at low levels in MCF10A and MCFNeoT but turned on or over-expressed in MCFT1 and MCFCA1. Adding antibodies specific for two of these molecules, Annexin-A1 and CEACAM1, inhibited macrophage activation, supporting their role as cancer "danger signals" recognized by macrophages.

EMS-effect of Exercises with Music on Fatness and Biomarkers of Obese Elderly Women

Background and objectives: Electromyostimulation (EMS) has been shown to improve body composition, but what biomarkers it affects has not been investigated. The purpose of this study was to compare the EMS-effect of exercises with music on fatness and biomarker levels in obese elderly. Materials and Methods: Twenty-five women were randomly classified into a control group (CON) and EMS group (EMSG). EMS suits used in this study enabled the simultaneous activation of eight pairs with selectable intensities. Program sessions of EMS were combined with exercises of listening to music three times a week for eight weeks. Although both groups received the same program, CON did not receive electrical stimuli. Results: Compared with CON, a significant effect of the EMS intervention concerning decreased fatness, as well as an increased skeletal muscle mass and basal metabolic rate, were evident. Tumor necrosis factor-a, C-reactive protein, resistin, and carcinoembryonic antigen of biomarkers were significantly different in the groups by time interaction. Similarly, the positive changes caused by EMS were represented in lipoprotein-cholesterols. Conclusions: The results indicate that a significant effect due to the EMS intervention was found concerning body composition and biomarkers in obese elderly women.

Inflammation in Primary and Metastatic Liver Tumorigenesis-Under the Influence of Alcohol and High-Fat Diets

The liver plays an outsized role in oncology. Liver tumors are one of the most frequently found tumors in cancer patients and these arise from either primary or metastatic disease. Hepatocellular carcinoma (HCC), the most prevalent form of primary liver cancer and the 6th most common cancer type overall, is expected to become the 3rd leading cause of cancer mortality in the US by the year 2030. The liver is also the most common site of distant metastasis from solid tumors. For instance, colorectal cancer (CRC) metastasizes to the liver in two-thirds of cases, and CRC liver metastasis is the leading cause of mortality in these patients. The interplay between inflammation and cancer is unmistakably evident in the liver. In nearly every case, HCC is diagnosed in chronic liver disease (CLD) and cirrhosis background. The consumption of a Western-style high-fat diet is a major risk factor for the development of non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH), both of which are becoming more prevalent in parallel with the obesity epidemic. Excessive alcohol intake also contributes significantly to the CLD burden in the form of alcoholic liver disease (ALD). Inflammation is a key component in the development of all CLDs. Additionally, during the development of liver metastasis, pro-inflammatory signaling is crucial in eliminating invading cancer cells but ironically also helps foster a pro-metastatic environment that supports metastatic seeding and colonization. Here we review how Westernized high-fat diets and excessive alcohol intake can influence inflammation within the liver microenvironment, stimulating both primary and metastatic liver tumorigenesis.

Serum Interleukin-17, Carcinoembryonic Antigen, and Prostate-Specific Antigen in High Lipid Profile Individuals

[Figure: see text] It is assumed that high lipid profile (HLP) causes chronic systemic inflammation, which ultimately leads to inflammatory diseases and cancers. The aim of the study was to investigate the serum concentration of proinflammatory/tumor markers of interleukin-17 (IL-17), carcinoembryonic antigen (CEA), and prostate-specific antigen (PSA) in HLP. HLP cases [F/M: 11/17 triglyceride (TG) >200 mg/dL, high-density lipoprotein (HDL) <50 mg/dL for females and HDL <40 mg/dL for males] and controls (F/M: 12/15, TG <200 mg/dL) were included. The volunteers with diabetes, high blood pressure, infection, cancer, inflammation, smoking addiction, drug consumption, and pregnancy were excluded. Serum TG, cholesterol, HDL and low-density lipoprotein were measured by routine biochemical procedures. The serum levels of IL-17, CEA, and PSA (only in men) were determined by enzyme-linked immunosorbent assay (ELISA). Independent samples t-test was used to compare the data in 2 groups and association between the variables tested by Pearson correlation. IL-17 in HLP group was statistically higher compared with the controls (3.43 ± 0.5 versus 2.28 ± 0.3 pg/mL, P < 0.001). The serum levels of CEA and PSA were not different in the HLP and controls. There was also a statistically positive linear association between TG and IL-17. In conclusion, abnormal high concentration of HLP and IL-17 could be a pathological condition and may cause to increase the chronic systemic inflammation and inflammatory diseases.

Carcinoembryonic antigen carrying SLeX as a new biomarker of more aggressive gastric carcinomas

Malignant transformation of gastric cells is accompanied by the deregulated expression of glycosyltransferases leading to the biosynthesis of tumor-associated glycans such as the sialyl-Lewis X antigen (SLe^x). SLe^x presence on cell surface glycoconjugates increases the invasive capacity of gastric cancer cells and is associated with tumor metastasis. ST3Gal IV enzyme is involved in the synthesis of SLe^x antigen and overexpressed in gastric carcinomas. Herein, we identified the glycoproteins carrying SLe^x in gastric cancer cells overexpressing ST3Gal IV enzyme and evaluated their biomarker potential for gastric carcinoma.

Methods: SLe^x modified glycoproteins were identified applying western blot and mass spectrometry. Immunoprecipitation, proximity ligation assay (PLA), E-selectin binding assay and CRISPR/cas9 knockout experiments were performed to characterize the presence of SLe^x on the identified glycoprotein. Protein N-glycans of the SLe^x protein carrier were in deep analyzed by porous-graphitized-carbon liquid-chromatography and tandem mass spectrometry glycomics. In silico expression analysis of α2-3 sialyltransferase ST3Gal IV and SLe^x protein carrier was performed and the conjoint expression of the SLe^x modified glycoproteins evaluated by immunohistochemistry and PLA in a series of gastric carcinomas.

Results: Carcinoembryonic antigen (CEA; CEACAM5) was identified and validated by different methodologies as a major carrier of SLe^x. N-glycomics of CEA revealed that complex N-glycans are capped with α2-3 linked sialic acid (Neu5Acα2-3Galβ1-4GlcNAc). Data set analysis of ST3Gal IV and CEA showed that ST3Gal IV expression was associated with patient´s poor survival, whereas CEA did not show any prognostic value. The co-expression of both CEA and SLe^X was observed in 86,3% of gastric carcinoma cases and 74,5% of the total cases displayed the conjoint CEA+SLe^xin situ PLA expression. This expression was associated with clinicopathological features of the tumors, including infiltrative pattern of tumor growth, presence of venous invasion and patient's poor survival. CEA immunoprecipitation from gastric carcinoma tissues also confirmed the presence of SLe^x.

Conclusion: CEA is the major glycoprotein carrying SLe^x in gastric carcinoma and the conjoint detection of CEA-SLe^x is associated with aggressive tumor features highlighting its PLA detection as a biomarker of gastric cancer patient prognosis for theranostic applications.

Association between serum carcinoembryonic antigen (CEA) levels and leukoaraiosis in middle-aged and older adults: A cross-sectional study

BACKGROUND

Leukoaraiosis refers to lesions of high signal intensities in periventricular and subcortical white matter, which result from chronic microvascular ischemic damage of the brain. Emerging evidence suggests that serum carcinoembryonic antigen (CEA) is elevated in cardiometabolic diseases, which are closely related with microangiopathy. Thus, we hypothesized that serum CEA levels could be associated with leukoaraiosis and aimed to examine this association among middle-aged and older adults.

METHODS

This cross-sectional study included 2164 Korean adults aged ≥ 45 years who underwent a health examination program at a single hospital between 2010 and 2015. Serum CEA levels were quantified by chemiluminescence immunoassay and categorized as quartiles: Q1: ≤ 1.1, Q2: 1.2-1.6, Q2: 1.7-2.4, and Q4: ≥ 2.5 μg/L. The odds ratios (ORs) and 95% confidence intervals (95% CIs) for leukoaraiosis based on brain MRI scans were calculated across serum CEA quartiles using multiple logistic regression analysis after adjusting for age, sex, body mass index, smoking status, fasting plasma glucose, triglyceride, HDL-cholesterol, hypertension, type 2 diabetes, and leukocyte count.

RESULTS

The overall prevalence of leukoaraiosis was 5.4% and increased with serum CEA quartiles: 3.3% for Q1, 5.0% for Q2, 5.8% for Q3, and 7.6% for Q4 (P < 0.001). The OR (95% CI) of the highest CEA quartile, compared to the lowest quartile, for leukoaraiosis was 2.164 (1.169-4.006) after adjusting for confounding variables.

CONCLUSIONS

Serum CEA levels were positively and independently associated with leukoaraiosis. Our findings indicate that serum CEA level might be useful additional measure in assessing leukoaraiosis in clinical settings.

Significant body mass increase by oral administration of a cascade of shIL21-MSTN yeast-based DNA vaccine in mice

Base on the practical of MSTN-specific yeast-based protein vaccine in mice as described previously, this research was designed for developing a better DNA vaccine (a cascade of shIL21-MSTN yeast-based DNA vaccine) than solely MSTN yeast-based DNA vaccine to block the endogenous MSTN in the murine model. We first constructed the target vectors, including CMV-driven MSTN expression vector and a combined shIL21-MSTN vector which containing MSTN expression cassette and shIL21 (short hairpin RNA-IL21) expression cassette. After necessary validation, recombinant yeast vaccines harboring different vectors were well prepared. Subsequently, after 2-month administration, the MSTN-specific immune response was detected with western blots. The commercial ELISA assays indicated that the production of IL21 and IL6 were decreased compared with control groups. More importantly, the MSTN-specific antibody titer was much higher in the shIL21-MSTN group than MSTN group, which was consistent with the western blots result. The most important finding was significant body mass increased after oral administration of these yeast-based DNA vaccines, in which the shIL21-MSTN vaccine is slightly higher than the sole MSTN vaccine in mice. In this study, we confirmed the role of different MSTN-specific yeast-based DNA vaccines on increasing body mass in mice, to provide a good inspiration for livestock breeding through the new type of immunoregulatory method. On the other hand, we also detected the possible modulating role of shIL21 on the dendritic cell-mediated immune function which needs more practical application and deeper exploration.

Water extract of ginseng and astragalus regulates macrophage polarization and synergistically enhances DDP's anticancer effect

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional Chinese medicine, supplementing Qi and strengthening body resistance are an important principle of anticancer treatment. Panax ginseng C.A.Mey. (ginseng) and Astragalus membranaceus Bunge (astragalus) are the representative herbs for this therapeutic principle.

AIM OF THE STUDY

This study aims to explore the effect of the water extract of ginseng and astragalus (WEGA) on regulating macrophage polarization and mediating anticancer in the tumor microenvironment.

MATERIALS AND METHODS

A549 cells were cultured in tumor-associated macrophage (TAM) supernatant with various concentrations of WEGA (0, 5, 10, 20 mg/mL). A549 cell proliferation was determined through methyl thiazole tetrazolium (MTT) assay and real-time cell analysis (RTCA), respectively. In vivo experiments were performed with a Lewis lung cancer (LLC) xenograft mouse model. Forty-eight mice were divided into six groups and treated with saline, WEGA, or cis-diamine dichloro platinum (DDP) with dosage of WEGA (0, 30, 60, 120 mg/kg body weight/day). The different groups were administered with drugs via oral or intraperitoneal injection once a day for 21 consecutive days. Tumor inhibition rate, spleen index, thymus index, cytokine, protein, and mRNA expression levels were detected in mice.

RESULTS

In a co-culture system, WEGA remarkably inhibited A549 cell proliferation, promoted the expression of M1 macrophage markers and inhibited M2 TAMs markers. Therefore, WEGA affected the biological behavior of cancer cells by regulating the expression of some markers relevant to macrophage polarization. In addition, the group of WEGA and DDP chemotherapy effectively inhibited the transplanted tumor growth in mice and improved weight loss and immunosuppressive with the cisplatin inducing.

CONCLUSIONS

This study provides mechanistic insights into the anticancer effect of WEGA through the regulation of macrophage polarization and highlights that WEGA could be a novel option for integrative cancer therapies.

Evaluation of serum inflammatory markers in treatment-resistant manic patients and adequate responder manic patients

Mania is accompanied with immune activation as indicated by increased pro-inflammatory cytokines, acute phase proteins; and carcinoembryonic antigen (CEA) is known to accompany signs of immune-inflammatory responses in bipolar disorder (BD) and medical disorders. In this study, it was aimed to compare high sensitivity C-reactive protein (hsCRP), CEA levels and white blood cells (WBCs) counts in the treatment-resistant BD (Group 3), the treatment-responsive BD patients (Group 2), and the healthy control group (Group 1). The sociodemographic data form, the Young Mania Rating Scale (YMRS), the Hamilton Depression Rating Scale (HDRS), and the Clinical Global Impression Severity of Illness (CGI-S) Scale were applied to the patients. In Group 3, the WBCs counts, and CEA levels were significantly higher than the other two groups. There was a positive correlation between WBCs counts and YMRS and CGI-S scores in all manic patients. There was a positive correlation between CEA levels and YMRS, HDRS and CGI-S in manic patients. This study shows that there is an activation of the immune-inflammatory response system in treatment resistant manic patients; and, WBCs counts and CEA levels are associated with severity of disease in manic patients.

CRP and LOX-1: a Mechanism for Increasing the Tumorigenic Potential of Colorectal Cancer Carcinoma Cell Line

Chronic inflammation and dyslipidemia are associated with an increase in the incidence of colorectal cancer (CRC). Serum C- reactive protein (CRP) and oxidized low-density lipoprotein (oxLDL), as Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) ligands, increase during inflammation and dyslipidemia, respectively. To evaluate the effects of CRP on the expression of important genes involved in the development of CRC, the CRC cell line, LS174T, was treated with the commercial CRP. Based on the Real-time PCR data, in the presence of CRP, LOX-1, CEA, MMP1, and MMP2 mRNA expression significantly increased, compared to the control group. Moreover, in the presence of CRP, secretion, and expression of CEA in the cell lysate and conditioned media increased in a concentration-dependent manner. The results of flow cytometry showed that expression of LOX-1 receptors at the cell surface increased significantly in the presence of 10 mg/L of CRP. However, inhibition of LOX-1 receptors with a specific monoclonal antibody reduced the effects of CRP on protein/mRNA expression. In conclusion, Increased CRP level, can potentially elevate the expression of important genes in CRC by stimulating LOX-1 receptors.

Nisin, a potent bacteriocin and anti-bacterial peptide, attenuates expression of metastatic genes in colorectal cancer cell lines

Colorectal cancer is the third most common cause of cancer-related death in the world which genetic and environmental agents are responsible for cancer. When cells detach from the tumor and invade surrounding tissues, the tumor is malignant and may form secondary tumors at other locations in a process called metastasis. Probiotics are the largest group of inhabitation bacteria in the colon. Gut microbiota has a central role in prevented the risk colon cancer. Probiotics are beneficial microorganisms, like Lactic acid bacteria and Lactobacilli bacteria which are using in the dairy industry. Probiotics nisin are having the most important category of safe usage. In this study LS180, SW48, HT29 and Caco2 was cultured and treated with different dose of nisin. Cell proliferation was assayed with MTT. The expression of CEA, CEAM6 and MMP2F genes was analyzed with Real-time PCR. Protein expression of CEA was evacuated with ELISA. Our result was shown that the 40-50 IU/mL nisin could suppress proliferation of LS180. Cell proliferation of SW48, HT29, Caco2 cells was decreased in 250-350 IU/mL concentration of nisin. The gene expression of CEA, CEAM6, MMP2F was significantly down-regulated with nisin treatment (p < 0.001, p < 0.01). Also, after cells treated with nisin, CEA protein expression was down regulated (p < 0.01). In conclusion, nisin could suppressed metastatic process via down-regulation of CEA, CEAM6, MMP2F, MMP9F genes. We suggested the new treatment strategies beyond Probiotics, which play a role in the prevention local tumor invasion, metastasis and recurrence.

Increased infiltration of macrophages to radioresistant lung cancer cells contributes to the development of the additional resistance of tumor cells to the cytotoxic effects of NK cells

In this study, in order to investigate the effects of increased macrophage infiltration to radioresistant lung tumors in regulating natural killer (NK) cell-mediated immunity, we examined whether the treatment of radioresistant cells with conditioned medium (CM) from phorbol myristate acetate (PMA)/interleukin (IL)-4 treated THP-1 cells (used as a tumor-associated macrophage source) leads to the development of the additional resistance of tumor cells to NK cell cytotoxicity. We found that the susceptibility of THP-1 CM-treated radioresistant cells to NK cell cytotoxicity was decreased compared to the non-treated cells. In addition, it was found that such a decreased susceptibility was associated with increased programmed death receptor ligand 1 (PD-L1) and decreased natural killer group 2D (NKG2D) ligand levels in tumor cells. We further discovered that the THP-1 cells secreted a high level of IL-6, and that blocking IL-6 action by the addition of a neutralizing antibody (Ab) for IL-6 into the THP-1 CM decreased the resistance of THP-1 CM-treated radioresistant cells to NK cell cytotoxicity. Moreover, we discovered that MEK/Erk was the most critical IL-6 downstream signaling pathway in triggering the THP-1 CM effect; thus, the addition of MEK/Erk inhibitor to THP-1 CM enhanced the susceptibility of the THP-1 CM-treated radioresistant cells to NK cell cytotoxicity. On the whole, the findings of this study suggest the existence of a malignant loop characterized by increased macrophage infiltration into radioresistant cells which, in turn, promotes the development of the additional resistance of these cells to NK cell cytotoxicity.

Carcinoembryonic antigen as a marker of radioresistance in colorectal cancer: a potential role of macrophages

Background

We sought to identify the carcinoembryonic antigen (CEA) as a marker of radioresistance in rectal cancer.

Methods

From July 1997 to January 2008, 104 patients with stage II or III rectal cancer who were treated with post-operative radiotherapy (PORT) were included in this study. The doses of radiotherapy ranged from 45 to 54.6 Gy. The CEA levels were measured before surgery. We analyzed the actuarial rates of overall survival (OS), distant metastasis (DM), and local recurrence (LR) using Kaplan-Meier curves. Multivariate analyses were performed with Cox regression models. We used THP-1 monocyte cell lines for macrophage differentiation (M0, M1 or M2). The RNA extracted from the macrophages was analyzed via a genomic method in the core laboratory. The radiosensitivities of CEA-rich LS1034 cells were compared between cells with and without the conditioned media from CEA-stimulated macrophages.

Results

Preoperative CEA levels ≥10 ng/mL were independent predictive factors for OS (p = 0.005), DM (p = 0.026), and LR (p = 0.004). The OS rates among the patients with pretreatment CEA levels < 10 ng/mL and ≥10 ng/mL were 64.5% and 35.9% (p = 0.004), respectively. The corresponding rates of DM were 40.6% and 73.1% (p = 0.024). The corresponding rates of LR were 6.6% and 33.9% (p = 0.002). In the M0 macrophages, exogenous CEA elicited a dose-response relationship with M2 differentiation. In the CEA-stimulated M0 cells, some mRNAs were upregulated by as much as 5-fold, including MMP12, GDF15, and JAG1. In the CEA-stimulated M2 cells, a 4-fold up-regulation of GADD45G mRNA was noted. The conditioned media from the CEA-stimulated M2 cells elicited an increase in the numbers of LS180, SW620, and LS1034 cells after irradiation. CEA caused the M2 differentiation of the macrophages.

Conclusion

Pretreatment CEA levels ≥10 ng/mL are a significant risk factor for OS, DM, and LR following PORT for rectal cancer. CEA causes radioresistance in the presence of M2 macrophages. More comprehensive examinations prior to surgery and intensive adjuvant therapy are suggested for patients with CEA levels ≥10 ng/mL. Further studies of these mechanisms are needed.

In vitro-induced M2 type macrophages induces the resistance of prostate cancer cells to cytotoxic action of NK cells

Previous reports, including our experimental results, showed that macrophages migrate to prostate cancer (PCa) cells. We tested whether the migrated macrophages affect the susceptibility of castration-resistant PCa (CRPC) cells to cytotoxic actions of natural killer (NK) cells. We found treatment of tumor cells with the conditioned media (CM) of the PMA/IL-4 treated THP-1 cells (M2 type macrophages) (THP-1 CM) decreased the susceptibility of tumor cells to NK cell cytotoxicity, as a result of increased programmed death receptor ligand 1 (PD-L1) and decreased NK group 2D (NKG2D) ligands in CRPC cells. Meanwhile, the decreased susceptibility of tumor cells was also detected when NK cells were treated with THP-1 CM and used in NK cell cytotoxicity tests. Therefore, we observed higher resistance of CRPC cells when both tumor and NK cells were treated with THP-1 CM than when tumor cells or NK cells were individually treated. We further discovered that the PMA/IL-4 treated THP-1 cells secrete a high level of IL-6, so blocking the IL-6 action significantly decreased the PD-L1 level while recovering the NKG2D ligands, thus increasing the susceptibility of CRPC cells to NK cell action. Moreover, we discovered that JAK-Stat3 is the most critical IL-6 downstream signaling in triggering the THP-1 CM effect. Consequently, we found the susceptibility of CRPC cells to NK cells was increased when either JAK or Stat 3 inhibitor was added when tumor cells were treated with THP-1 CM, and that the best effect was observed when the JAK inhibitor and PD-L1 Ab were added together.

Carbohydrate Antigen 19-9 Increases the Predictive Efficiency of a-Fetoprotein for Prognosis of Resected Hepatocellular Carcinoma

Serum α-fetoprotein (AFP) is a classical biomarker for both diagnosis and prognosis of hepatocellular carcinoma (HCC). However, its predictive efficiency for prognosis remains unsatisfactory. This study explores whether integrating AFP and carbohydrate antigen (CA) 19-9/carcinoembryonic antigen (CEA) increase its prognostic efficiency in HCC. A total of 67 HCC patients with complete record of AFP, CA19-9, and CEA, who underwent radical hepatectomy, were included. The sole and combined evaluations for prognostic significance of the three markers were performed. In the first, it was found by one-factor analysis that AFP was a univariate prognostic indicator for disease-free survival, but not overall survival, whereas CEA and CA19-9 were not statistically significant, although the latter was of marginally predictive significance for disease-free survival. Subsequently, it was revealed that combined evaluation of AFP and CA19-9, rather than AFP and CEA, distinguished overall and disease-free survival more effectively, compared with single ones. However, this combination was not significant in multivariate Cox regression analysis, thus needing further validation, especially in large-scale prospective investigations. The addition of vascular invasion to AFP/CA19-9 combination might provide enhanced predictive power for disease-free survival. Collectively, these results preliminarily suggest that CA19-9 increases the predictive efficiency of AFP for prognosis of HCC after resection.

The role of vitamin D in hepatic metastases from colorectal cancer

Colorectal cancer (CRC) represents a significant health burden worldwide, comprising approximately 10% of annual cancer cases globally. Hepatic metastases are the most common site of CRC metastasis, and are the leading cause of death in CRC patients. There is strong epidemiologic evidence for an inverse association between vitamin D status and risk of CRC; however, the role of vitamin D in the natural history of liver metastases has not yet been investigated. Several researchers have proposed hallmarks of metastases; crucially, metastases can be blocked by interrupting just one rate-limiting step. Vitamin D status has been implicated in each proposed hallmark of metastasis. The aim of this review is to examine the potential role for vitamin D in reducing the development of hepatic metastases from CRC and outline the candidate mechanisms by which vitamin D may mediate these effects. The results of ongoing randomised intervention trials are eagerly awaited to determine whether addressing vitamin D insufficiency in CRC patients could reduce the occurrence of liver metastases, and the consequent morbidity and mortality.

Serum carcinoembryonic antigen is positively associated with leukocyte count in Korean adults

BACKGROUND

Emerging evidence shows that serum carcinoembryonic antigen (CEA) levels may modestly be increased in non-neoplastic conditions such as cardiometabolic diseases, which are increasingly being seen as inflammatory diseases. Leukocyte count is widely evaluated marker of inflammation in clinical practice and a useful predictor of cardiometabolic disease. In this study, we aimed to determine the relationship between serum CEA levels and leukocyte counts in Korean adults.

METHODS

This cross-sectional study included a total of 19 834 individuals enrolled from a health promotion center between November 2006 and July 2010. Multiple linear regression analysis was performed to investigate the association between serum CEA levels and leukocyte counts after adjusting for confounding variables.

RESULTS

According to both stepwise-method and enter-method multiple linear regression analyses, serum CEA levels were positively and independently associated with leukocyte counts (P<.001) after adjusting for age, sex, body mass index, systolic blood pressure, diastolic blood pressure, total cholesterol, triglyceride, HDL-cholesterol, cigarette smoking, alcohol ingestion, physical activity, diabetes mellitus, and anti-inflammatory drugs.

CONCLUSIONS

We demonstrate a positive relationship between serum CEA levels and leukocyte counts in Korean adults. Our results suggested that an elevated serum CEA level may reflect chronic inflammation state.

One Year Follow-Up Risk Assessment in SKH-1 Mice and Wounds Treated with an Argon Plasma Jet

Multiple evidence in animal models and in humans suggest a beneficial role of cold physical plasma in wound treatment. Yet, risk assessment studies are important to further foster therapeutic advancement and acceptance of cold plasma in clinics. Accordingly, we investigated the longterm side effects of repetitive plasma treatment over 14 consecutive days in a rodent full-thickness ear wound model. Subsequently, animals were housed for 350 days and sacrificed thereafter. In blood, systemic changes of the proinflammatory cytokines interleukin 1β and tumor necrosis factor α were absent. Similarly, tumor marker levels of α-fetoprotein and calcitonin remained unchanged. Using quantitative PCR, the expression levels of several cytokines and tumor markers in liver, lung, and skin were found to be similar in the control and treatment group as well. Likewise, histological and immunohistochemical analysis failed to detect abnormal morphological changes and the presence of tumor markers such as carcinoembryonic antigen, α-fetoprotein, or the neighbor of Punc11. Absence of neoplastic lesions was confirmed by non-invasive imaging methods such as anatomical magnetic resonance imaging and positron emission tomography-computed tomography. Our results suggest that the beneficial effects of cold plasma in wound healing come without apparent side effects including tumor formation or chronic inflammation.

The CD44-Mediated Uptake of Hyaluronic Acid-Based Carriers in Macrophages

CD44 is a potentially rewarding target in cancer therapy, although its mechanisms of ligand binding and internalization are still poorly understood. In this study, we have established quantitative relationships between CD44 expression in differently polarized macrophages (M0, M1, and M2-polarized THP-1 human macrophages) and the uptake of hyaluronic acid (HA)-based materials, which are potentially usable for CD44 targeting. We have validated a robust method for macrophage polarization, which sequentially uses differentiating and polarizing factors, and allows to show that CD44 expression depends on polarization (M1 > M0 ≥ M2). It is noteworthy that THP-1 M2 expressed CD44v6, suggesting their suitability as a model of tumor-associated macrophages. In the uptake of HA, both as a soluble polymer and in the form of (siRNA-loaded) nanoparticles, CD44 expression correlated positively with binding, but negatively with internalization. Counterintuitively, it appears that a higher presence of CD44 (in M1) allows a more efficient capture of HA materials, but a lower expression (in M2) is conducive to better internalization. Although possibly cell-specific, this unexpected relationship indicates that the common paradigm "higher CD44 expression = better targetability" is too simplistic; mechanistic details of both receptor presentation and association still need to be elucidated for a predictable targeting behavior.

IL-6 Mediates Macrophage Infiltration after Irradiation via Up-regulation of CCL2/CCL5 in Non-small Cell Lung Cancer

Radiotherapy is effective in reducing primary tumors, however, it may enhance macrophage infiltration to tumor sites, accelerating tumor progression in several ways. We investigated whether radiation can increase macrophage infiltration into non-small cell lung carcinoma (NSCLC) cells. Analysis of in vitro macrophage (differentiated THP-1 cells) migration to either nonirradiated or irradiated tumor cells showed increased migration to the irradiated tumor cells. Because the IL-6 levels in A549 and H157 cells were significantly increased after irradiation, we then investigated whether this increased IL-6 level contributes to radiation-induced macrophage migration. Radiation-induced macrophage infiltration was reduced when IL-6 was knocked down in tumor cells, indicating a positive IL-6 role in this process. To validate this in vitro result, an orthotopic mouse model was developed using a luciferase-tagged H157siIL-6/scramble control (sc) cell set. After tumors developed, the lungs were irradiated, and infiltration of endogenous macrophages and tail-vein injected fluorescent macrophages to tumor sites was investigated. In both groups, increased macrophage infiltration was observed in H157sc cell-derived xenografts compared to H157siIL-6 cell-derived xenografts, confirming the positive IL-6 role in the radiation-induced macrophage infiltration process. In mechanistic dissection studies, radiation-induced up-regulation of CCL2 and CCL5 by IL-6 was detected, and blocking the action of CCL2/CCL5 molecules significantly reduced the number of migrated macrophages to tumor cells after irradiation. These results demonstrate that targeting the IL-6 signaling or CCL2/CCL5 molecules in combination with conventional radiotherapy potentially blocks undesired radiation-induced macrophage infiltration.

Prognostic Significance of a Tumor Marker Index Based on Preoperative Serum Carcinoembryonic Antigen and Krebs von den Lungen-6 Levels in Non-Small Cell Lung Cancer

Background: We retrospectively analysed the prognostic significance of a tumor marker index (TMI) based on preoperative serum carcinoembryonic antigen (CEA) and Krebs von den Lungen-6 (KL-6) levels in nonsmall cell lung cancer (NSCLC) patients. Materials and Methods: We enrolled 176 NSCLC patients who had preoperative serum CEA and KL-6 level measurements and had undergone curative surgery between 2009 and 2011. Results: The 5-year disease-specific survival of patients with high serum CEA levels was significantly poorer compared with that of patients with normal levels. The value for patients with high serum KL-6 levels was also poor. Patients with both normal serum CEA and KL-6 levels had a favourable prognosis, whereas those with both high serum CEA and KL-6 levels had a poor outcome. The5-year disease-specific survival rate was 82.9% for patients in the low TMI group compared to 47.5% in the high TMI group (p<0.01). Both univariate and multivariate analyses revealed prognostic significance for TMI. Conclusions: TMI based on preoperative serum CEA and KL-6 levels might be useful for the prediction of the prognosis of NSCLC patients.

Liver metastases: Microenvironments and ex-vivo models

The liver is a highly metastasis-permissive organ, tumor seeding of which usually portends mortality. Its unique and diverse architectural and cellular composition enable the liver to undertake numerous specialized functions, however, this distinctive biology, notably its hemodynamic features and unique microenvironment, renders the liver intrinsically hospitable to disseminated tumor cells. The particular focus for this perspective is the bidirectional interactions between the disseminated tumor cells and the unique resident cell populations of the liver; notably, parenchymal hepatocytes and non-parenchymal liver sinusoidal endothelial, Kupffer, and hepatic stellate cells. Understanding the early steps in the metastatic seeding, including the decision to undergo dormancy versus outgrowth, has been difficult to study in 2D culture systems and animals due to numerous limitations. In response, tissue-engineered biomimetic systems have emerged. At the cutting-edge of these developments are ex vivo 'microphysiological systems' (MPS) which are cellular constructs designed to faithfully recapitulate the structure and function of a human organ or organ regions on a milli- to micro-scale level and can be made all human to maintain species-specific interactions. Hepatic MPSs are particularly attractive for studying metastases as in addition to the liver being a main site of metastatic seeding, it is also the principal site of drug metabolism and therapy-limiting toxicities. Thus, using these hepatic MPSs will enable not only an enhanced understanding of the fundamental aspects of metastasis but also allow for therapeutic agents to be fully studied for efficacy while also monitoring pharmacologic aspects and predicting toxicities. The review discusses some of the hepatic MPS models currently available and although only one MPS has been validated to relevantly modeling metastasis, it is anticipated that the adaptation of the other hepatic models to include tumors will not be long in coming.

Avoiding hepatic metastasis naturally: Lessons from the cotton top tamarin (Saguinus oedipus)

Much has been written about hepatic metastasis and animal models abound. In terms of the human experience, progress in treating this final common pathway, a terminal event of many human malignancies has been relatively slow. The current thinking is that primary prevention is best served by early detection of cancer and eradication of early stage cancers by screening. Some cancers spread early in their course and the role of screening may be limited. Until relatively recently there has not been a pathfinder model that makes the evasion of this unfortunate event a reality. This review discusses such an animal model and attempts to relate it to human disease in terms of intervention. Concrete proposals are also offered on how scientists may be able to intervene to prevent this deadly progression of the cancer process.

Association between high serum carcinoembryonic antigen and clinical state of male anorexia nervosa: A case report

Anorexia nervosa (AN) is a complex psychiatric disorder, which is not yet fully understood. Several studies reported that AN was associated with disruption of cytokine network. Carcinoembryonic antigen (CEA) is a glycoprotein related to its network, used as a tumor marker of adenocarcinoma, and suggested to stimulate monocytes and macrophages to release proinflammatory cytokines. Here, we report a 41-year-old male suffering from AN who was suspected of having a malignant tumor due to markedly elevated serum CEA levels. However, on further examinations, he was discovered to have no malignant tumors, and, interestingly, his CEA levels actually decreased as his clinical state of AN improved. Furthermore, it was found that his CEA levels were elevated proportionally to his clinical state of AN and that his body mass index was significantly correlated with serum CEA levels. Therefore, it is suggested that inflammatory responses may be associated with the clinical state of AN.

Serum levels of carcinoembryonic antigen (CEA) in patients with bipolar disorder

OBJECTIVE

Carcinoembryonic antigen (CEA) is an oncofetal glycoprotein that is widely used as a tumour marker in adenocarcinomas. However, several non-neoplastic conditions, including acute and chronic inflammation and other inflammation-related conditions, are characterised by increased CEA concentrations. Bipolar disorder (BD) ranks seventh among the worldwide burden of non-fatal diseases. Inflammatory biomarkers have been considered as one of the main key pillars of a multifactorial approach for prediction of BD in an at-risk population. BP is accompanied by activation of inflammatory, cell-mediated and negative immunoregulatory cytokines.

METHODS

We measured the levels of CEA in serum samples from 44 individuals with euthymic BP out-patients and 45 healthy controls. Patients were diagnosed according to the DSM-IV criteria. CEA was measured by an electrochemiluminescence immunoassay.

RESULTS

The mean serum CEA concentration was 2.36±1.52 and 1.77±0.98 µg/l in patients and controls, respectively. CEA levels were significantly increased in euthymic BP patients when compared with controls (p=0.031).

CONCLUSIONS

This study suggests that CEA is increased in BD and supports a role for immune activation in the core pathological mechanisms of BP. CEA levels may be a secondary marker for diagnosing BP.

Higher serum carcinoembryonic antigen levels associate with more frequent development of incident fractures in Korean women: a longitudinal study using the national health insurance claim data

BACKGROUND

Pro-inflammatory cytokines play important roles in bone metabolism and several studies have shown that carcinoembryonic antigen (CEA) may promote inflammation. We investigated the association of serum CEA levels with the risk of osteoporosis and incident fracture.

METHODS

We performed a small cross-sectional study with 302 Korean women and a large, longitudinal study with 7192 Korean women in an average 3-year follow-up period. For the cross-sectional study, bone mineral density (BMD) and bone turnover markers (BTMs) were measured. For the longitudinal study, incident fractures in the follow-up period were identified by using the selected International Classification of Diseases, 10th revision (ICD-10) codes and the nationwide claims database of the Health Insurance Review and Assessment Service of Korea.

RESULTS

In the cross-sectional study, serum CEA levels correlated negatively with BMD at the lumbar spine (γ=-0.023; P=0.029) and positively with BTMs (γ=0.122 to 0.138, P=0.002 to P<0.001) after adjustment for confounding variables. In the longitudinal study, 254 (3.5%) women developed incident fractures in the follow-up period (2.8±1.3 years). After adjustment for potential confounders, the hazard ratio (HR) per 1 ng/mL increment of the baseline CEA level for the development of incident fracture was 1.22 [95% confidence interval (CI): 1.05-1.42]. The HR was markedly higher in subjects in the highest CEA quartile category compared with those in the lowest CEA quartile category (HR=1.54, 95% CI: 1.04-2.28).

CONCLUSION

Therefore, serum CEA may be a biomarker of the risk of incident fracture in postmenopausal Korean women.

Proper exercise decreases plasma carcinoembryonic antigen levels with the improvement of body condition in elderly women

Aging increases the risk of chronic diseases including cancers. Physical exercise has the beneficial effects for the elderly susceptible to the development of cancers, through maintaining a healthy body condition and improving the immune system. However, excessive or insufficient exercise might increase the risk for cancer. In the present study, we investigated what exercise frequency improves cancer-related biomarkers, such as carcinoembryonic antigen (CEA), alpha fetoprotein (AFP), red blood cell (RBC), and white blood cell (WBC), and the body composition of elderly women. Fifty-four females, aged 70 to 77 years, were divided into 4 groups: control, 1-day exercise (1E), 2-3-day exercise (2-3E), and 5-day exercise (5E) groups. The control group did not participate in any physical activity, while the subjects in the exercise groups underwent the exercise program for 12 weeks. As results, CEA was significantly decreased in the exercise groups, with the lowest values in 2-3E group. In contrast, AFP, RBC and WBC were not significantly changed. CEA is an oncofetal glycoprotein that is overexpressed in adenocarcinomas. Although the function of CEA has not been fully understood, CEA has been suggested to be involved in the release of pro-inflammatory cytokines via stimulating monocytes and macrophages. Moreover, body weight and body mass index were improved in the exercise groups, with the lowest levels in 5E group. Thus, we suggest that exercise for 2-3 days per week decreases the expression of CEA and improves body condition, without loading fatigue or stress, which may contribute to preventing cancer in the elderly women.

The increase of carcinoembryonic antigen (CEA), high-sensitivity C-reactive protein, and neutrophil/lymphocyte ratio in Parkinson's disease

The role of carcinoembryonic antigen (CEA) in Parkinson's disease (PD) has not been previously investigated. The aim of the present study was to evaluate the serum level of carcinoembryonic antigen, high-sensitivity C-reactive protein (hs-CRP), and Neutrophil/lymphocyte ratio (NLR) among patients with Parkinson's disease and to examine the relationship between these inflammatory markers. The cross-sectional design includes 51 patients with Parkinson's disease and 50 age- and sex-matched healthy controls. We investigated the differences in hs-CRP, CEA, and NLR levels between these two groups. CEA was significantly higher in PD patients relative to the control group (mean 2.40 ± 1.51 vs. 1.72 ± 0.87 (ng/mL), respectively; p = 0.015). Mean NLR was significantly higher in PD patients relative to the control group (mean 3.1 ± 1.3 vs. 2.1 ± 0.32, respectively; p < 0.001). Serum level of hs-CRP was higher in PD patients than in control group (mean 1.04 ± 0.62 and 0.54 ± 0.31, respectively; p < 0.01). Correlation analysis revealed significant correlation between hs-CRP, CEA, and Neutrophil/lymphocyte ratio (p < 0.05). This study demonstrates for the first time the association between CEA, hs-CRP, NLR, and PD. We found CEA, hs-CRP, and NLR levels to be significantly higher in the PD patients than in the normal controls.

Correlations of tumor-associated macrophage subtypes with liver metastases of colorectal cancer

OBJECTIVE

This work aimed to investigate the correlations of tumor-associated macrophages (TAMs) and their subtypes M1 and M2 with liver metastasis of colorectal cancer, and provide useful references for seeking predictors of liver metastasis and studying mechanisms.

METHODS

120 patients with colorectal cancer from 2000 to 2009 were divided into low, middle and high liver metastasis groups (group A, B and C, respectively). S-P immunohistochemical staining and microscopic observation were conducted to compare expression in CD68- positive cells (TAMs), CD80-positive cells (M1) and CD163-positive cells (M2) in three groups. Correlations of TAMs, M1, M2, and M2/M1 ratio with clinical and pathological parameters were analyzed.

RESULTS

With increase of liver metastatic ability, the number of TAMs decreased gradually, with no significant difference between any two of the three groups (P > 0.05), while the numbers of M1 and M2 were significantly decreased and increased, respectively, with significant difference between any two of three groups (P < 0.05 or P < 0.01). In addition, the M2/M1 ratio increased with increase of liver metastatic ability (P < 0.01). There was no statistical significance of correlation of TAMs with each clinical and pathological parameter. M1 was negatively related with lymphatic metastasis and liver metastatic ability. M2 was positively correlated with preoperative CEA level, lymphatic metastasis, tumor differentiation degree and liver metastatic ability. The same was the case for the M2/M1 ratio.

CONCLUSIONS

Effects of TAMs on liver metastasis of colorectal cancer do not depend on the total number of TAMs, but on the number and proportion of functional subtypes M1 and M2. M2 number and M2/ M1 ratio are more accurate predictors for liver metastasis of colorectal cancer.

Natural history of hepatic metastases from colorectal cancer - pathobiological pathways with clinical significance

Colorectal cancer hepatic metastases represent the final stage of a multi-step biological process. This process starts with a series of mutations in colonic epithelial cells, continues with their detachment from the large intestine, dissemination through the blood and/or lymphatic circulation, attachment to the hepatic sinusoids and interactions with the sinusoidal cells, such as sinusoidal endothelial cells, Kupffer cells, stellate cells and pit cells. The metastatic sequence terminates with colorectal cancer cell invasion, adaptation and colonisation of the hepatic parenchyma. All these events, termed the colorectal cancer invasion-metastasis cascade, include multiple molecular pathways, intercellular interactions and expression of a plethora of chemokines and growth factors, and adhesion molecules, such as the selectins, the integrins or the cadherins, as well as enzymes including matrix metalloproteinases. This review aims to present recent advances that provide insights into these cell-biological events and emphasizes those that may be amenable to therapeutic targeting.

Factors Associated with Serum Levels of Carcinoembryonic Antigen in Healthy Non-smokers

BACKGROUND

Carcinoembryonic antigen (CEA), a serological marker of malignant tumors, demonstrates a modest increase under nonmalignant conditions such as aging and smoking. Also, recent study results suggested that serum CEA levels may be related to insulin resistance or low-grade inflammation. The aim of this study was to investigate the factors associated with serum CEA levels in healthy non-smokers.

METHODS

Data was gathered from 21,501 adults aged 20 and over. We excluded 19,081 subjects who had omissions in anthropometric measurements or laboratory tests, or who had previous or current smoking history.

RESULTS

The mean CEA level was 1.18 ± 0.85 ng/dL in males and 0.93 ± 0.73 ng/dL in females. After adjustment for age, CEA level was positively correlated with fasting glucose, glycosylated hemoglobin (HbA1C), high density lipoprotein (HDL) cholesterol, estimated glomerular filtration rate in males. In females, CEA level was positively correlated with fasting glucose, HbA1C, HDL cholesterol, aspartate aminotransferase, and high-sensitivity C-reactive protein. In both gender groups, HbA1C had a strong influence on CEA levels when all other variables were included in the regression model (P < 0.05).

CONCLUSION

Within normal range, serum CEA levels were significantly associated with HbA1C levels but not with homeostasis model assessment of insulin resistance in the non-smoking population. These findings suggest that serum CEA levels are influenced by the glucose level itself instead of insulin resistance.

Macrophages promote tumour growth and liver metastasis in an orthotopic syngeneic mouse model of colon cancer

PURPOSE

Tumour-associated macrophages have been shown to promote proliferation, angiogenesis and metastasis in several carcinomas. The effect on colon cancer has not yet been clarified. Furthermore, Kupffer cells in the liver might initiate the formation of metastases by directly binding tumour cells.

METHODS

An orthotopic syngeneic mouse model of colon cancer as well as a liver metastases model has been studied, using murine CT-26 colon cancer cells in Balb/c-mice. Macrophages were depleted in both models by clodronate liposomes. Tumour sizes and metastases were determined using 7-Tesla MRI. The macrophage and vascular density in the orthotopic tumours as well as the Kupffer cell density in the livers were evaluated using immunohistochemistry.

RESULTS

Animals in the macrophage-depleted group displayed significantly smaller primary tumours (37 ± 20 mm(3)) compared to the control group (683 ± 389 mm(3), p = 0.0072). None of the mice in the depleted group showed liver or peritoneal metastases, whereas four of six control mice displayed liver and five out of six mice peritoneal metastases. The vascular density was significantly lower in the macrophage-depleted group (p = 0.0043). In the liver metastases model, animals of the Kupffer cell-depleted group (14.3 ± 7.7) showed significantly less liver metastases than mice of the two control groups (PBS liposomes, 118.5 ± 28.2, p = 0.0117; NaCl, 81.7 ± 23.2, p = 0.0266). The number of liver metastases correlated directly with the Kupffer cell density (p = 0.0221).

CONCLUSION

Macrophages promote tumour growth, angiogenesis and metastases in this orthotopic syngeneic mouse model. Kupffer cells enhance the formation of metastases in the liver.

Regulation of carcinoembryonic antigen release from colorectal cancer cells

Clinical and experimental evidence suggest that circulating carcinoembryonic antigen (CEA) released from tumor cells has an instrumental role in colorectal cancer-liver metastasis. However, the precise mechanism of the regulation of the CEA release from cancer cells is not known. We investigated if the rate of CEA and another GPI-anchored protein, alkaline phosphatase (AP) release is correlated with cellular glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) expression. We also evaluated the effects of phosphatidic acid (PA), a compound known to inhibit GPI-PLD activity, on the CEA and AP release from colon cancer cells. The expression of CEA, GPI-PLD, and AP in five colon carcinoma cells (LS180, Caco2, SW742, SW1116, and HT29/219) was verified by immunoblot and real-time RT-PCR analysis. The amounts of CEA and AP released into cell culture media were determined using ELISA and a colorimetric assay, respectively. We examined the effects of PA (20-100 μM) on CEA and AP release from LS180 cells. All five cancer cell lines analyzed expressed GPI-PLD protein. While there was a positive relationship between AP release and the levels of GPI-PLD transcript expression, we found no direct correlation between CEA released from cancer cells and the GPI-PLD mRNA expression level. However, the rate of CEA release was positively associated with the level of CEA transcript expression. In comparison to controls, the release of GPI-anchored CEA and AP, but not CA19-9 was inhibited significantly by both crude and pure phosphatidic acid (by 56 and 54.5%, respectively). Using PA for inhibiting CEA release from cancer cells may have therapeutic application in preventing CRC-liver metastasis.

Mechanistic control of carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1) splice isoforms by the heterogeneous nuclear ribonuclear proteins hnRNP L, hnRNP A1, and hnRNP M

Carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1) is expressed in a variety of cell types and is implicated in carcinogenesis. Alternative splicing of CEACAM1 pre-mRNA generates two cytoplasmic domain splice variants characterized by the inclusion (L-isoform) or exclusion (S-isoform) of exon 7. Here we show that the alternative splicing of CEACAM1 pre-mRNA is regulated by novel cis elements residing in exon 7. We report the presence of three exon regulatory elements that lead to the inclusion or exclusion of exon 7 CEACAM1 mRNA in ZR75 breast cancer cells. Heterologous splicing reporter assays demonstrated that the maintenance of authentic alternative splicing mechanisms were independent of the CEACAM1 intron sequence context. We show that forced expression of these exon regulatory elements could alter CEACAM1 splicing in HEK-293 cells. Using RNA affinity chromatography, three members of the heterogeneous nuclear ribonucleoprotein family (hnRNP L, hnRNP A1, and hnRNP M) were identified. RNA immunoprecipitation of hnRNP L and hnRNP A1 revealed a binding motif located central and 3' to exon 7, respectively. Depletion of hnRNP A1 or L by RNAi in HEK-293 cells promoted exon 7 inclusion, whereas overexpression led to exclusion of the variable exon. By contrast, overexpression of hnRNP M showed exon 7 inclusion and production of CEACAM1-L mRNA. Finally, stress-induced cytoplasmic accumulation of hnRNP A1 in MDA-MB-468 cells dynamically alters the CEACAM1-S:CEACAM1:L ratio in favor of the l-isoform. Thus, we have elucidated the molecular factors that control the mechanism of splice-site recognition in the alternative splicing regulation of CEACAM1.

Pathobiology of colorectal cancer hepatic metastases with an emphasis on prognostic factors

Colorectal cancer is the second leading cause of cancer related death in the United States. The majority of these deaths are due to metastasis, with the liver easily accounting as the most common site of deposit. While there are multiple steps in the CRC hepatic metastatic cascade, this review attempts to summarize the different processes involved, focusing on the most recent discoveries, as well as the associated effects in relation to prognosis.

Carcinoembryonic antigen concentrations in patients with acute coronary syndrome

BACKGROUND

Carcinoembryonic antigen (CEA), one of the most widely used tumor markers, has been recently associated with carotid atherosclerosis. The aim of our study was to evaluate whether CEA concentrations have a role in coronary artery disease (CAD).

METHODS

Serum CEA concentrations were evaluated in 89 patients, including 50 patients with acute coronary syndrome (ACS) (Group I, 44 with acute myocardial infarction, six with unstable angina, 38 males, 65 ± 2 years) and 39 patients with stable CAD (Group II, 33 males, 66 ± 3 years). In addition, 33 subjects (16 males, 62 ± 2 years) were also included as a control group (Group III).

RESULTS

ACS was significantly associated with increased mean CEA concentrations (3.1 ± 0.3 vs. 1.75 ± 0.1 and 1.7 ± 0.2 ng/mL in Groups I, II and III, respectively, p < 0.001). Increased CEA concentrations remained an independent determinant for ACS (OR=3.1, 95% CI=1.2-7.9, p < 0.05) after correcting for other significant risk factors.

CONCLUSIONS

CEA might represent a potential new candidate biomarker for the prediction of risk associated with ACS.

Serum carcinoembryonic antigen is associated with metabolic syndrome in female Korean non-smokers

BACKGROUND

Carcinoembryonic antigen (CEA), a serological marker of malignant tumors, demonstrates a modest increase under nonmalignant conditions and the pro-inflammatory features of CEA suggest that CEA may be related to insulin resistance and metabolic syndrome.

METHODS

A total of 7075 female Korean non-smokers who underwent health check-ups were analyzed in the present study. The interquartile cutoff values for serum CEA concentrations were 0.39, 0.84, and 1.40 ng/ml.

RESULTS

The prevalence of metabolic syndrome increased significantly with the increasing CEA quartiles, and the age-adjusted mean CEA concentration increased consistently with each additional component of metabolic syndrome. Logistic regression analysis adjusted for age, alcohol intake, exercise, body mass index, total cholesterol, WBC count, and hsCRP showed that the third and fourth CEA quartiles were associated with metabolic syndrome with odds ratios of 1.29 (95% CI 1.07 to 1.63 P<0.001) and 1.39 (95% CI 1.10 to 1.66, P<0.001), respectively.

CONCLUSION

In female Korean non-smokers, serum CEA was independently associated with metabolic syndrome. The pathophysiologic and clinical significance of these findings requires further investigation.

Serum sE-selectin levels and carcinoembryonic antigen mRNA-expressing cells in peripheral blood as prognostic factors in colorectal cancer patients

BACKGROUND

This study analyzed the possible prognostic value of presurgical serum soluble (s)E-selectin levels and/or carcinoembryonic antigen (CEA) mRNA positivity in predicting the disease-free survival of colorectal cancer (CRC) patients.

METHODS

CEA mRNA (obtained from blood-borne cells by reverse transcriptase-polymerase chain reaction [RT-PCR]), tumor necrosis factor-alpha (TNF-alpha), and sE-selectin levels were analyzed in blood samples obtained from 78 patients with primary (n = 62) or recurrent (n = 16) CRC, 40 patients with benign colorectal (CR) diseases, and 78 controls.

RESULTS

CEA mRNA positivity by RT-PCR was significantly associated with advanced stage (P < .05). Median baseline sE-selectin levels were higher in patients with CRC (43 ng/mL) compared with controls (36 ng/mL) or patients with benign CR diseases (31 ng/mL, P < .001). These were significantly associated with CEA mRNA positivity by RT-PCR (P < .05). Multivariate analysis by forward stepping showed that elevated TNF-alpha (P = .001) and CEA mRNA positivity by RT-PCR (P = .0001) were independent predictors of elevated baseline sE-selectin levels. Positive presurgical sE-selectin levels were associated with an increased recurrence rate compared with patients with low levels of this molecule (P < .001). Positivity for both CEA mRNA and sE-selectin had a negative prognostic impact, with a 5-year recurrence-free survival rate of 51% compared with 95% of patients with negative parameters (P < .05).

CONCLUSIONS

Detection of presurgical serum sE-selectin levels and CEA mRNA-positive blood-borne cells in CRC patients might provide useful prognostic information in terms of recurrence-free survival, either alone or in combination, and may help in the choice of more aggressive treatment and/or more strict follow-up procedures in high-risk patients.

Role of Kupffer cells in the outgrowth of colorectal cancer liver metastases

Colorectal cancer is one of the commonest malignancies in the "developed" world. The liver constitutes the main host organ for its distant metastases which, when present, augur a bad prognosis for the disease. Kupffer cells (KCs) are macrophages that constantly reside within the liver and form an effective first line defence against multiple harmful agents which reach the hepatic sinusoids via the portal circulation. KCs remove chemical compounds and dead or damaged cells, eliminate bacteria and protect against invading tumour cells. They may play a crucial tumouricidal role, exerting cytotoxic and cytostatic functions through the release of multiple cytokines and chemokines. Subsequently, colorectal metastasising cells are destroyed either by KC-performed phagocytosis or via the stimulation of other immune cells which migrate into the sinusoids and act accordingly. On the contrary, KC products, including cytokines, growth factors and matrix-degrading enzymes may promote liver metastasis, supporting tumour cell extravasation, motility and invasion. Current research aims to exploit the antineoplastic properties of KCs in new therapeutic approaches of colorectal cancer liver metastasis. Numerous agents, such as the granulocyte macrophage-colony stimulating factor, interferon gamma, muramyl peptide analogues and various antibody based treatments, have been tested in experimental models with promising results. Future trials may investigate their use in everyday clinical practice and compare their therapeutic value with current treatment of the disease.

Are serum carcinoembryonic antigen levels associated with carotid atherosclerosis in Japanese men?

OBJECTIVE

Carcinoembryonic antigen (CEA), a serological marker of malignant tumors, may show a modest increase under some nonmalignant conditions, such as ageing and cigarette smoking. We have investigated whether serum CEA levels are associated with early carotid atherosclerosis.

METHODS AND RESULTS

Cross-sectional data from 4181 male individuals who underwent general health screening were analyzed. The interquartile of cutoff values of serum CEA levels were 1.0, 1.6, and 2.5 ng/mL. Cigarette smoking was associated with increased serum CEA levels in a dose- and duration-dependent manner, and this association was more prominent in current than former smokers. Logistic regression analysis adjusted for age, body mass index, serum lipid and glucose profiles, white blood cell count, C-reactive protein, and smoking habits showed that the first, second, third, and fourth CEA quartiles were associated with carotid plaque with an odds ratio of 1 (reference), 1.25 (95% CI 1.03 to 1.52, P=0.023), 1.49 (95% CI 1.23 to 1.82 P<0.001), and 1.34 (95% CI 1.08 to 1.65, P=0.007), respectively. Although serum CEA levels were associated with metabolic syndrome, association between serum CEA and carotid plaque was significant in individuals without metabolic syndrome.

CONCLUSIONS

Serum CEA was associated with carotid atherosclerosis independently of atherogenic risk factors and markers of inflammation. Our data suggest that a slight elevation of CEA in current smokers, as well as in never smokers, may not be an innocuous observation from the viewpoint of atherosclerosis.

Stepping out of the flow: capillary extravasation in cancer metastasis

In order for cancer cells to successfully colonize a metastatic site, they must detach from the primary tumor using extracellular matrix-degrading proteases, intravasate and survive in the circulation, evade the immune response, and extravasate the vasculature to invade the target tissue parenchyma, where metastatic foci are established. Though many of the steps of metastasis are widely studied, the precise cellular interactions and molecular alterations associated with extravasation are unknown, and further study is needed to elucidate the mechanisms inherent to this process. Studies of leukocytes localized to inflamed tissue during the immune response may be used to elucidate the process of cancer extravasation, since leukocyte diapedesis through the vasculature involves critical adhesive interactions with endothelial cells, and both leukocytes and cancer cells express similar surface receptors capable of binding endothelial adhesion molecules. Thus, leukocyte extravasation during the inflammatory response has provided a model for transendothelial migration (TEM) of cancer cells. Leukocyte extravasation is characterized by a process whereby rolling mediated by cytokine-activated endothelial selectins is followed by firmer adhesions with beta1 and beta2 integrin subunits to an activated endothelium and subsequent diapedesis, which most likely involves activation of Rho GTPases, regulators of cytoskeletal rearrangements and motility. It is controversial whether such selectin-mediated rolling is necessary for TEM of cancer cells. However, it has been established that similar stable adhesions between tumor and endothelial cells precede cancer cell transmigration through the endothelium. Additionally, there is support for the preferential attachment of tumor cells to the endothelium and, accordingly, site-specific metastasis of cancer cells. Rho GTPases are critical to TEM of cancer cells as well, and some progress has been made in understanding the specific roles of the Rho GTPase family, though much is still unknown. As the mechanisms of cancer TEM are elucidated, new approaches to study and target metastasis may be utilized and developed.