Carcinoembryonic Antigen Production Research Articles

Relations of carcinoembryonic antigen (CEA) staining of cancer tissue and serum CEA levels to histologic response in patients with locally advanced rectal cancer (LARC) who received neoadjuvant chemoradiotherapy (nCRT).

790 Background: Neoadjuvant chemoradiotherapy (nCRT) is a standard of care for LARC. The serum CEA level is a predictor of the response to nCRT; however, the relation between CEA production immunohistochemically evaluated in cancer tissue and treatment response remains unclear. Methods: The study group comprised 145 patients with clinical Stage II/III rectal cancer who received nCRT followed by surgery from 2005 through 2013. The radiation dose was 40 to 45 Gy. UFT- or S-1-based chemotherapy was given concurrently. Surgery was performed 6 to 8 weeks after the completion of radiotherapy. Immunohistological CEA staining patterns in biopsy tissue obtained before nCRT were evaluated. Specimens in which the luminal cell membrane or the cytoplasm was strongly stained were defined as staining positive. The histologic response was evaluated on the basis of the pathological complete response (ypCR) rate, T downstaging, tumor regression grade (TRG), and tumor shrinkage rate on MRI. Results: CEA staining in biopsy specimens and serum CEA levels were both negative in 17 patients (11.7%) and both positive in 72 patients (49.7%). There was no relation between the groups (p = 0.174). In patients with negative CEA staining, the rates of ypCR, T downstaging, marked regression, and mean tumor shrinkage were 24.3%, 51.4%, 45.9%, and 72.3%, respectively. In patients with positive CEA staining, these rates were 11.1%, 48.1%, 37.0%, and 72.8%, respectively. CEA staining of cancer tissue was not significantly related to the ypCR rate, T downstaging, a marked regression rate, or the tumor shrinkage rate on MRI (p = 0.060, p = 0.849, p = 0.436, and p = 0.874, respectively). Patients with negative serum CEA levels before nCRT had significantly higher rates of ypCR, T downstaging, marked regression, and tumor shrinkage on MRI than did patients with positive serum CEA levels (p = 0.014, p = 0.006, p = 0.002, and p = 0.014, respectively). Conclusions: Serum CEA levels before nCRT were a significant predictor of the histologic response to nCRT; in contrast, tissue CEA staining before nCRT was unrelated to the histologic response to nCRT.

Cerebrospinal fluid abnormalities in meningeosis neoplastica: a retrospective 12-year analysis

BackgroundMeningeosis neoplastica is a diffuse metastatic spread of tumor cells in the subarachnoid space. Although first recognized in 1870, systematic investigations regarding cerebrospinal fluid (CSF) constituents in this condition are scarce.MethodsRoutine CSF samples analyzed from 2001 to 2012 at the Laboratory of Clinical Neurochemistry, University of Göttingen, were re-evaluated. Patients, whose CSF contained malignant cells were included in this study.ResultsPatients (n = 132, age 59.1 ± 29.1, 58% women) were identified, whose CSF contained malignant cells. The most frequent primary tumor was breast cancer (32.6%), followed by lung cancer (25.0%) and hematologic malignancies (21.2%). The most frequent clinical symptoms were affections of cranial nerves (41.7%), psychiatric abmormalities (32.6%) and radicular lesions of the lower extremities (20.5%). CSF cell counts ranged from 0 to 4692 cells/μl (median 4 cells/μl) and were elevated in 50%. The CSF-to-serum albumin ratio was abnormal in 69.4%. It ranged from 1.8 to 330 x 10-3 (median 17.5 x 10-3). Total CSF protein ranged from 166 to 15,840 mg/l (median 1012 mg/l). CSF lactate was elevated (>2.4 mmol/l) in 65.2% [3.6 mmol/l (1.3/15.6 mmol/l); median (minimum/maximum)]. In 50% of all patients CSF lactate was ≥3.5 mmol/l. The CSF cell counts correlated significantly with the CSF lactate levels and the CSF protein contents. In 56 of 118 CSF samples (47.5%) ferritin was elevated, and in 25 of 65 carcinoma patients (38.5%) an intrathecal production of carcinoembryonic antigen (CEA) was detected. Granulocytes were found in 52.7% of the CSF samples. The percentages of granulocytes and lymphocytes were higher in samples with an elevated cell count.ConclusionIn approximately 50% of CSF samples with meningeosis neoplastica the CSF cell count is not elevated. Diagnosis may be missed when only CSF samples with elevated cell counts are subjected to cytological analysis. CSF lactate and protein and the CSF-to-serum albumin ratio are frequently increased in meningeosis neoplastica. The differential diagnosis between meningeosis neoplastica and central nervous infections, in particular tuberculous or fungal meningitis, can be difficult.

Relation between Carcinoembryonic Antigen Levels in Colon Cancer Tissue and Serum Carcinoembryonic Antigen Levels at Initial Surgery and Recurrence

Objectives: Carcinoembryonic antigen (CEA) is widely used for postoperative surveillance of colon cancer. Even if serum CEA is negative at initial surgery, it may turn positive at recurrence. We investigated the relation between serum CEA levels and the immunohistochemical staining status of CEA in the primary and resected metastatic tissues. Methods: Out of 224 patients with recurrent colon cancer between 1998 and 2012, we studied 46 patients in whom serum CEA levels were measured and immunohistochemical staining for CEA was possible in the primary and metastatic tissues. Results: The positive rate of serum CEA did not differ between initial surgery and recurrence, regardless of whether the cutoff value was set at 5 or 10 ng/ml (p = 0.829, p = 0.671). There was no relation between the CEA staining status and serum CEA level at initial surgery. However, the CEA staining status of metastatic tissue was significantly related to the serum CEA level at recurrence (p = 0.0046 and p = 0.0026). Conclusions: The immunohistochemical staining status of CEA in metastatic tissue is closely related to the serum CEA level. This finding suggests that serum CEA levels are influenced not only by the CEA production capacity of cancer cells but also by the ability of the surrounding tissue to release CEA into the blood.

Impact of RAS and BRAF mutations on carcinoembryonic antigen production and pattern of colorectal metastases.

To investigate the impact of RAS and BRAF mutations on the pattern of metastatic disease and carcinoembryonic antigen (CEA) production. In this retrospective study, we investigated the impact of RAS and BRAF mutational status on pattern of metastatic disease and CEA production. Only patients presenting with a newly diagnosed metastatic colorectal cancer (CRC) were included. Patients' characteristics, primary tumor location, site of metastatic disease and CEA at presentation were compared between those with and without RAS and BRAF mutations. Among 174 patients, mutations in KRAS, NRAS and BRAF were detected in 47%, 3% and 6% respectively. RAS mutations (KRAS and NRAS) were more likely to be found in African American patients (87% vs 13%; P value = 0.0158). RAS mutations were associated with a higher likelihood of a normal CEA (< 5 ng/mL) at presentation. BRAF mutations were more likely to occur in females. We were not able to confirm any association between mutational status and site of metastatic disease at initial diagnosis. No association was found between RAS and BRAF mutations and sites of metastatic disease at the time of initial diagnosis in our cohort. Patients with RAS mutations were more likely to present with CEA levels < 5 ng/mL. These findings may have clinical implications on surveillance strategies for RAS mutant patients with earlier stages of CRC.

T125: Effect of carcinoembryonic antigen production by colorectal cancer cells on tumor microenvironment and cancer progression

Tumor markers play an important role in the identification of human malignancies. It has been shown that the carcinoembryonic antigen (CEA, CEACAM5) is a promoter of metastasis in epithelial cancers that is widely used as a clinical marker. The aim of this study is to elucidate the network of genes that are involved in the CEA-induced liver metastasis. Previously, we have shown that CEA is accumulated in the lungs and livers of rats by interacting with their macrophages. We identified and cloned a new gene (CEAR) for the CEA-binding protein, which is located on the surface of fixed liver macrophages, Kupffer cells (Bajenova et al, 2001). It has been shown that the interaction of CEA and CEAR proteins increases the production of IL-1, IL-10, IL-6, TNF- α cytokines (Thomas et al, 2011). This interaction changes the expression of liver adhesion molecules that enhances the survival of cancer cells to the liver. We also suggested that CEA synthesis by cancer cells may influence the E-cadherin adhesion junction complexes and have shown that CEA production violates the functional relationship between Ecadherin and its partners α -, β - and p120 catenin. A new type of interaction was discovered between the CEA and β -catenin and the increased amount of β -catenin in the nuclei of CEA producing cells. The data show that CEA production can cause the dissociation of cancer cells and trigger cancer progression. The CEA synthesis also alters splicing of p120 catenin protein and causes the release of soluble E-cadherin. Previously, CEA and epithelial E-cadherin were considered as independent tumor markers. Our data explain the correlation between the elevated levels of CEA and the increase in soluble E-cadherin in the progression of colorectal cancer (Bajenova et al, 2014). We carried out a comparative transcriptome analysis of CEA-producing cell lines. The RNA transcriptome libraries were obtained and sequenced. By pairwise comparisons of CEA producing and non-producing cell lines using Cummerband program, we selected the set of genes (90 total genes) whose expression have been changed in the CEA-producing cell lines (overexpressed or downregulated). The biological processes that are linked to this differential gene expression were identified by Gene Set Enrichment Analysis (GSEA). In total, 8 significantly enriched GO terms related to the cellular components and biological processes were identified. Using KEGG and GO databases, we also identified the signaling pathways involved in the response to CEA. These findings have direct medical application, since they allow not only to establish the relationships between the existing biomarkers but also to discover the new ones. These biomarkers can be used for diagnosis and monitoring of metastatic carcinomas and for the drug development.

Relation between carcinoembryonic antigen (CEA) production in colorectal cancer (CRC) tissue and serum CEA levels: Comparison between the time of recurrence and initial diagnosis.

561 Background: Because serum CEA often becomes positive before the diagnosis of recurrence, CEA is widely used for postoperative surveillance. Serum CEA is negative at initial diagnosis as well as at recurrence in some patients. We examined the relation between serum CEA levels and tissue CEA staining status both at initial surgery and at recurrence. Methods: Between 1998 to 2012, 1,306 patients (pts) with colon cancer (CC) underwent curative resection. Serum CEA levels were measured at initial surgery and at recurrence and immunohistochemical staining for CEA in primary and metastatic lesions was performed in 46 pts. Serum CEA levels of 10ng/mL or more were regarded as positive. Results: Serum CEA were positive in 17 pts (37%) at initial surgery and in 20 (43%) at recurrence. CEA staining was positive in primary lesions in 24 pts (52%) and metastatic lesions in 33 (72%). The positive rate was higher in metastatic lesions (p=0.053). Among pts in whom serum CEA was positive at initial surgery, CEA staining in primary lesion was positive in 12 pts (71%) and negative in 5 (29%). Among pts in whom serum CEA was negative, CEA staining in primary lesion was positive in 12 pts (41%) and negative in 17 (59%). Serum CEA at initial surgery was not related to CEA staining in primary lesion(p=0.0722). Among pts positive for serum CEA at recurrence, CEA staining in metastatic lesions was positive in 19 pts(95%) and negative in 1(5%). Among pts negative for CEA at recurrence, CEA staining in metastatic lesions was positive in 14 pts (54%) and negative in 12 (46%). Serum CEA at recurrence was significantly related to CEA staining in metastatic lesions (p=0.0026). Among 33 pts in whom CEA staining was positive at recurrence, serum CEA was negative in 14 (42%). Conclusions: In pts with recurrence of CC, there was no relation between the staining CEA status and serum CEA level at initial diagnosis. In contrast, these variables were significantly related at recurrence. However, 42% of pts with positive staining for CEA in metastatic lesions had negative serum CEA levels. Our findings suggest that factors besides the production of CEA by cancer cells are related to serum CEA levels.

Carcinoembryonic antigen-related cell adhesion molecule 4 (CEACAM4) is specifically expressed in medullary thyroid carcinoma cells.

Carcinoembryonic antigen (CEA), an oncofetal cell surface glycoprotein, has been widely used as a human tumor marker due to its high expression in tumors and secretion to serum. It belongs to the immunoglobulin superfamily named CEA-related cell adhesion molecule (CEACAM) family. Members of this family are detected in various cancers and have been shown to be involved in cancer growth and invasion. In this study, we examined the mRNA expression profiles of CEACAM family members including CEACAM1, CEACAM3, CEACAM4, CEACAM5 (CEA), CEACAM6, CEACAM7, and CEACAM8 in various tumor cell lines. Our screening data indicated that the mRNA expression patterns of CEACAMs in TT cells, which are derived from medullary thyroid carcinoma (MTC), were distinct from other tumor cell lines. Additionally, CEACAM4 was only expressed in TT cells, in which two novel splice variants of CEACAM4 were expressed. These findings suggested that production of CEA and CEA-related molecules in MTC may be distinct from other tumor-based production of those molecules and that the specific expression of CEACAM4 would make possible to differentiate between MTC and other CEA-producing tumors.

Carcinoembryonic antigen expression level as a predictive factor for response to 5-fluorouracil in colorectal cancer

Carcinoembryonic antigen (CEA) expression has been shown to protect cancer cell lines from apoptosis and anoikis. The aim of this study was to further elucidate the role of CEA expression on resistance to anticancer drugs in human colorectal cancer (CRC). We transfected CEA negative CRC cell line SW742 as well as CHO cells to overexpress CEA and their chemoresistance were assessed by MTT assay. In comparison to the parental cell lines, transfected cells had significantly increased resistance to 5-fluorouracil (5-FU). The results also showed a direct correlation between the amount of cellular CEA protein and 5-FU resistance in CEA expressing cells. We found no significant difference in sensitivity to cisplatin and methotrexate between CEA-transfected cells and their counter parental cells. We also compared the association between CEA expression and chemoresistance of 4 CRC cell lines which differed in the levels of CEA production. The CEA expression levels in monolayer cultures of these cell lines did not correlate with the 5-FU resistance. However, 5-FU treatment resulted in the selection of sub-populations of resistant cells that displayed increased CEA expression levels by increasing drug concentration. We analyzed the effect of 5-FU in a 3D multicellular culture generated from the two CRC cell lines, LS180 and HT29/219. Compared with monolayer culture, CEA production and 5-FU resistance in both cell lines were stimulated by 3D growth. In comparison to the 3D spheroids of parental CHO, we observed a significantly elevated 5-FU resistance in 3D culture of the CEA-expressing CHO transfectants. Our findings suggest that the CEA level may be a suitable biomarker for predicting tumor response to 5-FU-based chemotherapy in CRC.

Drug-resistant colon cancer cells produce high carcinoembryonic antigen and might not be cancer-initiating cells

PurposeWe evaluated the higher levels of carcinoembryonic antigen (CEA) secreted by the LoVo human colon carcinoma cells in a medium containing anticancer drugs. Drug-resistant LoVo cells were analyzed by subcutaneously xenotransplanting them into mice. The aim of this study was to evaluate whether the drug-resistant cells isolated in this study were cancer-initiating cells, known also as cancer stem cells (CSCs).MethodsThe production of CEA was investigated in LoVo cells that were cultured with 0–10 mM of anticancer drugs, and we evaluated the increase in CEA production by the LoVo cells that were stimulated by anticancer drug treatment. The expression of several CSC markers in LoVo cells treated with anticancer drugs was also evaluated. Following anticancer drug treatment, LoVo cells were injected subcutaneously into the flanks of severe combined immunodeficiency mice in order to evaluate the CSC fraction.ResultsProduction of CEA by LoVo cells was stimulated by the addition of anticancer drugs. Drug-resistant LoVo cells expressed lower levels of CSC markers, and LoVo cells treated with any of the anticancer drugs tested did not generate tumors within 8 weeks from when the cells were injected subcutaneously into severe combined immunodeficiency mice. These results suggest that the drug-resistant LoVo cells have a smaller population of CSCs than the untreated LoVo cells.ConclusionProduction of CEA by LoVo cells can be stimulated by the addition of anticancer drugs. The drug-resistant subpopulation of LoVo colon cancer cells could stimulate the production of CEA, but these cells did not act as CSCs in in vivo tumor generation experiments.

Engineered measles virus Edmonston strain used as a novel oncolytic viral system against human hepatoblastoma

BackgroundHepatoblastoma (HB) is the most common primary, malignant pediatric liver tumor in children. The treatment results for affected children have markedly improved in recent decades. However, the prognosis for high-risk patients who have extrahepatic extensions, invasion of the large hepatic veins, distant metastases and very high alpha-fetoprotein (AFP) serum levels remains poor. There is an urgent need for the development of novel therapeutic approaches.MethodsAn attenuated strain of measles virus, derived from the Edmonston vaccine lineage, was genetically engineered to produce carcinoembryonic antigen (CEA). We investigated the antitumor potential of this novel viral agent against human HB both in vitro and in vivo.ResultsInfection of the Hep2G and HUH6 HB cell lines, at multiplicities of infection (MOIs) ranging from 0.01 to 1, resulted in a significant cytopathic effect consisting of extensive syncytia formation and massive cell death at 72–96 h after infection. Both of the HB lines overexpressed the measles virus receptor CD46 and supported robust viral replication, which correlated with CEA production. The efficacy of this approach in vivo was examined in murine Hep2G xenograft models. Flow cytometry assays indicated an apoptotic mechanism of cell death. Intratumoral administration of MV-CEA resulted in statistically significant delay of tumor growth and prolongation of survival.ConclusionsThe engineered measles virus Edmonston strain MV-CEA has potent therapeutic efficacy against HB cell lines and xenografts. Trackable measles virus derivatives merit further exploration in HB treatment.

Carcinoembryonic antigen (CEA) and its receptor hnRNP M are mediators of metastasis and the inflammatory response in the liver

This article discusses the role of carcinoembryonic antigen (CEA) as a facilitator of the inflammatory response and its effect on colorectal cancer hepatic metastasis. Colorectal cancer accounts for 11% of all cancers in the United States and the majority of deaths are associated with liver metastasis. If left untreated, median survival is only six to 12months. Resection of liver metastases offers the only chance for cure. Of the small number of patients who have operable cancer most will have further tumor recurrence. The molecular mechanisms associated with colorectal cancer metastasis to the liver are largely unknown. However CEA production has been shown both clinically and experimentally to be a factor in an increased metastatic potential of colorectal cancers to the liver. CEA also has a role in protecting tumor cells from the effects of anoikis and this affords a selective advantage for tumor cell survival in the circulation. CEA acts in the liver through its interaction with its receptor (CEAR), a protein that is related to the hnRNP M family of RNA binding proteins. In the liver CEA binds with hnRNP M on Kupffer cells and causes activation and production of pro- and anti-inflammatory cytokines including IL-1, IL-10, IL-6 and TNF-α. These cytokines affect the up-regulation of adhesion molecules on the hepatic sinusoidal endothelium and protect the tumor cells against cytotoxicity by nitric oxide (NO) and other reactive oxygen radicals. HnRNP M signaling in Kupffer cells appears to be controlled by beta-adrenergic receptor activation. The cells will respond to the β-adrenergic receptor agonist terbutaline resulting in reduced TNF-α and increased IL-10 and IL-6 production following CEA activation. This has implications for the control of tumor cell implantation and survival in the liver.

Possible association of CEA expression with oxyphilic change but not with C-cell hyperplasia in Hashimoto's thyroiditis

Reactive C-cell hyperplasia (CCH) has been observed in cases of autoimmune Hashimoto's thyroiditis; however, its occurrence in Graves' disease, the other major autoimmune disorder, has not yet been investigated. On the other hand, although Carcinoembryonic Antigen (CEA) serum levels have been reported elevated in patients with autoimmune thyroid disease (ATD), the source of CEA production at the cellular level is not elucidated. The aim of this study was to evaluate CCH and CEA immunohistochemical expression and comparatively analyze them in 136 ATD cases (107 Hashimoto's and 29 Graves' disease cases) and 20 cases of nodular hyperplasia (NH). Immunohistochemistry using monoclonal antibodies to chromogranin and CEA was performed. A scoring system for CCH and semiquantitative evaluation for CEA expression were applied. C-cell hyperplasia was absent in NH cases. In contrast, it was detected in 11% of ATD cases being more frequently observed in Hashimoto's (12.1%) than Graves' disease (6.8%) CCH associated to male sex and older age of Hashimoto's patients. CEA was detected only in ATD cases (33.8%), in C-cells and in follicular cells as well, being more frequently detected in Graves' (44.8%) than Hashimoto's (30.8%) disease. An interesting finding was an emerging possible association of CEA expression with oxyphilic change but not with C-cell hyperplasia in Hashimoto's thyroiditis. No significant correlation was established between CCH and CEA follicular cell expression in neither disease. In conclusion, C-cell hyperplasia and CEA expression may be encountered in the setting of Hashimoto's thyroiditis and Graves' disease.

Engineered measles virus as a novel oncolytic therapy against prostate cancer

No curative therapy is currently available for locally advanced or metastatic prostate cancer. Oncolytic viruses represent a novel class of therapeutic agents that demonstrates no cross-resistance with existing approaches and can therefore be combined with conventional treatment modalities. Measles virus strains deriving from the Edmonston (MV-Edm) vaccine strain have shown considerable oncolytic activity against a variety of solid tumers and hematologic malignancies. In this study, we investigated the antitumor potential of recombinant MV-Edm derivatives as novel oncolytic agents against prostate cancer. The susceptibility of prostate cancer cell lines (PC-3, DU-145, and LNCaP) to measles virus infection was demonstrated using an MV-Edm derivative expressing green fluorescent protein (GFP). MV-Edm replication in prostate cancer cell lines was assessed by one step viral growth curves. The oncolytic effect of an MV-Edm strain engineered to express the human carcinoembryonic antigen (CEA) was demonstrated in vitro by MTT assays and in vivo in subcutaneous PC-3 xenografts. CEA levels were quantitated in cell supernatants and mouse serum samples. Recombinant MV-Edm strains can effectively infect, replicate in and kill prostate cancer cells. Intratumoral administration of MV-CEA at a total dose of 6 x 10(6) TCID50 resulted in statistically significant tumor growth delay (P = 0.004) and prolongation of survival (P = 0.001) in a subcutaneous PC-3 xenograft model. Viral growth kinetics paralleled CEA production. MV-CEA has potent antitumor activity against prostate cancer cell lines and xenografts. Viral gene expression during treatment can be determined by monitoring of CEA levels in the serum; the latter could allow dose optimization and tailoring of individualized treatment protocols.

Establishment of a carcinoembryonic antigen-producing cell line from human pancreatic carcinoma.

A human pancreatic carcinoma cell line of islet cell origin (QGP-1) has been established and maintained for over two years. The parent tumor and the cultured cell line produce carcinoembryonic antigen (CEA), and there is no evidence of hormone secretion from the tumor cells. The epithelioid cells, which had migrated from rounded, irregular cell aggregates, grow as a confluent monolayer with piling up of cells in some areas, and have a population doubling time of 3.5 days. The modal chromosome number was 50. Exponentially growing cultures produce 76.3 ng of CEA/10(6) cells after 7 days. CEA production was confirmed by immuno-peroxidase staining.

Carcinoembryonic antigen production in human gastric cancer cell lines in vitro and in nude mice.

A quantitative study of carcinoembryonic antigen (CEA) was made in nine human gastric cancer cell lines. Six of them were found to produce CEA in vitro. The production of CEA in the three cell lines derived from well differentiated tubular adenocarcinomas began at the mid-exponential phase of cell growth and reached its peak at the late stationary phase, the amount of CEA per 10(5) cells and the frequency of CEA-positive cells on immunostaining increased with culture time. In contrast, CEA in the three cell lines derived from poorly differentiated adenocarcinomas including a signet-ring cell carcinoma was produced immediately after plating and the amount of the antigen per 10(5) cells and the frequency of CEA-positive cells were almost constant throughout the cell growth phases. Serum CEA content in nude mice was low or not detectable in the case of subcutaneous heterotransplantation of gastric cancer cells, irrespective of CEA productivity of the cell lines in vitro. Intraperitoneal inoculation, however, led to high CEA levels in sera of nude mice bearing human gastric cancers. No significant difference was found between the two kinds of inoculation in terms of the total tumor weight and the frequency of CEA-positive cells in tumor tissues. One reason for the above findings may be that the transport of CEA in the subcutaneous tumors to the systemic blood flow is hindered.

Primary Mucinous Adenocarcinoma of Renal Pelvis with Carcinoembryonic Antigen Production

We report a case of primary mucinous adenocarcinoma of the renal pelvis associated with carcinoembryonic antigen (CEA) production. A 48-year-old woman was incidentally found to have an elevated serum CEA level. A series of examinations revealed a fat-containing tumor in the left kidney and excluded tumors in other sites. Radical nephrectomy was performed, and the histopathologic examination revealed a mucinous adenocarcinoma that was strongly positive for CEA. Postoperatively, her serum CEA level gradually returned to the normal range, and she had had no recurrence by 9 months postoperatively.

Large-cell carcinoma of the lung with a remarkable preoperative elevation of serum carcinoembryonic antigen level

Carcinoembryonic antigen, a serum tumor marker, is useful for diagnosing cancer and for following the response to therapy in cancer cases. Serum carcinoembryonic antigen levels are also important as a predictive tool in evaluating prognosis. A 56-year-old man presented with an abnormal shadow on a chest X-ray. His preoperative serum carcinoembryonic antigen was at an elevated level of 1274.0 ng/ml. Chest computed tomography revealed a tumor in the posterior segment of the right lung and a swollen right interlobar lymph node. Right lung pneumonectomy and node dissection were performed. A histological diagnosis determined that the tumor was a large-cell carcinoma at clinical stage IIA. Immunohistochemical analysis detected the production of carcinoembryonic antigen by the tumor cells. Following surgery, the patient's carcinoembryonic antigen levels were maintained within the normal range. This is a rare case of lung cancer with no evidence of recurrence and metastasis for 8 years despite markedly elevated preoperative carcinoembryonic antigen levels.

A measles virus vaccine strain derivative as a novel oncolytic agent against breast cancer

Breast cancer is the most common malignancy and the second leading cause of female cancer mortality in the United States. There is an urgent need for development of novel therapeutic approaches. In this study, we investigated the antitumor potential of a novel viral agent, an attenuated strain of measles virus deriving from the Edmonston vaccine lineage, genetically engineered to produce carcinoembryonic antigen (CEA) against breast cancer. CEA production as the virus replicates can serve as a marker of viral gene expression. Infection of a variety of breast cancer cell lines including MDA-MB-231, MCF7 and SkBr3 at different multiplicities of infection (MOIs) from 0.1 to 10 resulted in significant cytopathic effect consisting of extensive syncytia formation and massive cell death at 72-96 h from infection. All breast cancer lines overexpressed the measles virus receptor CD46 and supported robust viral replication, which correlated with CEA production. TUNEL assays indicated an apoptotic mechanism of syncytial death. The efficacy of this approach in vivo was examined in a subcutaneous Balb C/nude mouse model of MDA-MB-231 cells. Intravenous administration of MV-CEA at a total dose of 1.2 x 10(7) TCID50 resulted in statistically significant tumor growth delay ( p=0.005) and prolongation of survival ( p=0.001). In summary, MV-CEA has potent antitumor activity against breast cancer lines and xenografts. Monitoring marker peptide levels in the serum could serve as a low-risk method of detecting viral gene expression during treatment and could allow dose optimization and individualization of treatment. Trackable measles virus derivatives merit further exploration in breast cancer treatment.

Effective production of carcinoembryonic antigen by conversion of the membrane-bound into a recombinant secretory protein by site-specific mutagenesis

Carcinoembryonic antigen (CEA), the most widely used human tumor marker, is a heavily glycosylated protein over-expressed by a wide range of tumors. It has been indicated that CEA might be a useful target for human anti-tumor immunotherapy. CEA assay for research as well as clinical trials demands a continuous source of CEA protein preparations. In a multi-purpose research program to provide a reliable source for large production of CEA, we converted the membrane-bound carcinoembryonic antigen into a secretory protein by site-specific mutagenesis. We made the secretory CEA protein by introducing a new stop codon at 99 bp upstream of the original stop codon in CEA cDNA by PCR-based mutagenesis. The glycosylation of recombinant CEA proteins, especially those destined for administration to human trials is crucially important. To produce CEA with the same glycosylation pattern and immunogenicity as the native CEA expressed by human tumors in vivo, the truncated CEA cDNA which does not encode the last C-terminal 33-amino acid hydrophobic domain was transfected into HT29, a human colon carcinoma cell line by the calcium phosphate method. Stable transfectants were selected and pooled. CEA secretion from the cells was verified by analysis of the transfectant culture supernatant for CEA protein. As determined by ELISA, 16 microg/L of recombinant CEA was secreted per 106 transfectants within 48 hrs, an increase over 40 times relative to the untransfected cells. The size of the recombinant CEA secreted by HT29 transfectants in our experiment is identical to that of reference CEA secreted from tumors and is fully antigenic. It seems that the C-terminal truncation does not affect CEA glycosylation in HT29 cells. It is predicted that human cancer immunotherapy using recombinant CEA expressed in this system would be more effective than the commercial protein which is usually prepared from bacterial or other heterologous expression systems.

Postoperative serum carcinoembryonic antigen levels in patients with pathologic stage IA nonsmall cell lung carcinoma: subnormal levels as an indicator of favorable prognosis.

Elevated serum carcinoembryonic antigen (CEA) levels are sometimes attributable to the production of CEA by malignant cells, and in turn, the antigen itself can enhance the metastatic potential of malignant cells. The authors speculated that low serum CEA levels might be indicative of relatively low levels of malignant cells and a low probability of disease recurrence. This hypothesis led them to investigate whether low CEA levels in serum represented a useful prognostic factor for patients with pathologic Stage IA nonsmall cell lung carcinoma. Between 1993 and 2001, 724 patients underwent surgery for NSCLC at Toneyama National Hospital (Toyonaka, Japan). Of these patients, the 242 who were diagnosed with pathologic Stage IA disease were included in the current study. Smoking behavior, gender, age, tumor diameter, disease histology, and preoperative and postoperative serum CEA levels were chosen as study variables, with the cutoff level between subnormal and normal serum CEA levels set at 2.5 ng/mL and the cutoff level between normal and high serum CEA levels set at 5.0 ng/mL. Prognostic indicators were evaluated using a Cox hazard model. In addition, survival probabilities were calculated using the Kaplan-Meier method, and differences in survival were assessed by log-lank analysis. Subnormal postoperative serum CEA levels were found to be an independent prognostic indicator (hazard ratio, 2.3; 95% confidence interval, 1.1-4.7; P = 0.03 for comparison with patients who had normal CEA levels) on multivariate analysis. Furthermore, the 5-year survival rate was 87% for patients with subnormal postoperative CEA levels (n = 146), compared with 75% for patients with normal postoperative CEA levels (n = 80) and 53% for patients with high postoperative CEA levels (n = 16) (P < 0.0001). Among patients with pathologic Stage IA NSCLC, those who had an extremely favorable prognosis were distinguished by their subnormal postoperative serum CEA levels.