Podcasts about carcinoembryonic

40% CHANCE OF DEATH - What would you do if you heard this from your doctor? In this week's podcast episode, we are joined by the force behind The Good Property Company, which has sourced more than 200+ properties, all in Bristol, with a value of over £45 million, at a purchase price of £30 million(before refurb) - SUSANNAH COLE.  And while all her achievements in property are amazing, you'll find Susannah to be even more so as she shares with us her story of how she's beaten not one, not two, but THREE cancers in a span of one year and the lessons she's learned along the way. Productivity hacks & important health lessons whilst building a property business - all this and more in Episode 31. All this and more in Episode 31!! Want to be more proactive about your health but stuck where to start? Here's a list that Susannah has compiled to make your journey a bit easier: Low cost easy to do, easy to organise and available privately UK wide and often on post.  Poo test (fit test) - testing for colon cancer, do 2 in 2 weeks for greater accordance Mammogram for women Blood tests for common cancer markers. CA125, CEA, PSA the most common. Do at least these 3 (PSA is only for men) Full body MRI For smokers, highly suggest doing a CT chest scan   Scientists are still learning about known tumor markers and discovering new tumor markers. Some tumor markers currently used include:   Alpha-fetoprotein (AFP) for liver cancer Beta 2-microglobulin (B2M) and lactate dehydrogenase (LDH) for blood cancers Calcitonin for thyroid cancer Cancer antigen 125 (CA 125) for ovarian cancer Cancer antigens 15-3 and 27-29 for breast cancer Carcinoembryonic antigen (CEA) for colorectal cancer, lung cancer, stomach cancer, pancreatic cancer and others Human chorionic gonadotropin (HCG) for testicular cancer and ovarian cancer Prostate-specific antigen (PSA) for prostate cancer   If you find all of this interesting and want to know more, connect with Susannah Cole and The Good Property Company using the links below: Website: https://thegoodpropertycompany.co.uk/ YouTube: https://www.youtube.com/c/TheGoodPropertyCompanySusannahCole Instagram: https://www.instagram.com/susannahcoleuk Facebook: https://www.facebook.com/SusannahColeTGPC If you're interested in taking the Wealth Dynamics test but don't know where to start, email us at hi@property-strategy.com Subscribe to our newsletter www.property-strategy.com/insights Visit our website at www.property-strategy.com Connect with Jackie at www.facebook.com/jackietomes1 www.instragram.com/tomesjackie www.linkedin.com/in/jackietomes/

Dr. Carline Crevecoeur is a Haitian-American retired board-certified obstetrician and gynecologist. Dr. Crevecoeur attended St. John's University as an undergraduate, earning a Bachelor's Degree in chemistry. She received her medical degree from Downstate Medical School, where she went on to complete her obstetric and gynecological training. Her medical concentration was in perinatology, where she researched lung development in premature infants. She also worked extensively with breast cancer patients and victims of sexual violence. After 20 years of medical service in New York and Pennsylvania, Dr. Crevecoeur gave up her career to raise and homeschool her five children. She nonetheless kept up with her medical education, and also volunteered at Centre Volunteers in Medicine as an obstetrician and gynecologist. Although she had planned to return to her beloved profession after her children were grown, a cancer diagnosis in 2012 sidelined her plans and forced her to retire. A few highlights from the show: 1. Reach out to others. You can't do it alone! 2. Cancers do change and mutate. 3. Education is all around us. We never stop learning. 4. Learn more about Carcinoembryonic antigen (CEA) tumor marker. https://news.cancerconnect.com/colon-cancer/understanding-the-cea-test-in-colon-cancer Follow and learn more about Carline at: https://www.carlinecrevecoeur.com/ https://twitter.com/medicrev https://www.instagram.com/crevey22/ About Me: In 2011, I was diagnosed with Hodgkin's Lymphoma, out of the blue. I did not have any prior health concerns or issues. Fast forward, the dreaded cancer diagnosis opened my eyes, introduced me to my purpose, and lead me to where I am today. As a Cancer Doula, I use my 10-years of experience with cancer to support and guide others diagnosed with cancer. Many people are not familiar with what a cancer doula is. Think of me as a personal health care advocate. Schedule a free 30-minute meet and greet call to learn more. https://bit.ly/OTOSDiscovery Looking for a gift for yourself, a friend, or a loved one who has been diagnosed with cancer or they are a caregiver? Visit my shop. Thanks for joining us on today's episode of the Navigating Cancer TOGETHER podcast! If you enjoyed today's episode, please head over to Apple Podcasts and leave a rate and review to help me reach even more people that are facing cancer. Make sure you visit On the Other Side, follow me on Instagram, or sign up for my bi-weekly newsletter to get information and resources related to cancer. https://www.ontheotherside.life/ --- Send in a voice message: https://anchor.fm/navigatingcancertogether/message Support this podcast: https://anchor.fm/navigatingcancertogether/support

Dr. Edward S. Kim from the Levine Cancer Institute in Charlotte, NC describes the use of serum tumor markers in various types of cancer, and the lack of a useful serum tumor marker in lung cancer.

Dr. Edward S. Kim from the Levine Cancer Institute in Charlotte, NC describes the use of serum tumor markers in various types of cancer, and the lack of a useful serum tumor marker in lung cancer.

Dr. Edward S. Kim from the Levine Cancer Institute in Charlotte, NC describes the use of serum tumor markers in various types of cancer, and the lack of a useful serum tumor marker in lung cancer.

Dr. Seong-Wook Lee discusses his manuscript, "An RNA Aptamer That Binds Carcinoembryonic Antigen Inhibits." To view the print version of this abstract, go to http://www.gastrojournal.org/article/S0016-5085%2812%2900462-3/abstract

The tumor marker carcinoembryonic antigen (CEA) is predominantly expressed in epithelial cells along the gastrointestinal tract and in a variety of adenocarcinomas. As a basis for investigating its in vivo regulation and for establishing an animal model for tumor immunotherapy, transgenic mice were generated with a 33-kilobase cosmid clone insert containing the complete human CEA gene and flanking sequences. CEA was found in the tongue, esophagus, stomach, small intestine, cecum, colon, and trachea and at low levels in the lung, testis, and uterus of adult mice of independent transgenic strains. CEA was first detected at day 10.5 of embryonic development (embryonic day 10.5) in primary trophoblast giant cells and was found in the developing gut, urethra, trachea, lung, and nucleus pulposus of the vertebral column from embryonic day 14.5 onwards. From embryonic day 16.5 CEA was also visible in the nasal mucosa and tongue. Because this spatiotemporal expression pattern correlates well with that known for humans, it follows that the transferred genomic region contains all of the regulatory elements required for the correct expression of CEA. Furthermore, although mice apparently lack an endogenous CEA gene, the entire repertoire of transcription factors necessary for correct expression of the CEA transgene is conserved between mice and humans. After tumor induction, these immunocompetent mice will serve as a model for optimizing various forms of immunotherapy, using CEA as a target antigen.

We have determined the precise chromosomal location, the exon structure, and the expression pattern of CGM2, a member of the carcinoembryonic antigen (CEA) gene family. CGM2 cDNA was amplified by reverse transcription-polymerase chain reaction (RT/PCR) from the colon adenocarcinoma cell line, LS174T. A defective exon is missing from this cDNA clone, leading to a novel domain organization for the human CEA family with two immunoglobulin-like domains. The derived C-terminal domain predicts that the CGM2 protein is membrane-bound through a glycosyl phosphatidylinositol anchor. RT/PCR analyses identified CGM2 transcripts in mucinous ovarian and colonic adenocarcinomas as well as in adjacent colonic tissue, but not in other tumors including leukocytes from six chronic myeloid leukemia patients. Thus, unlike several other family members, CGM2 is not expressed in granulocytes but reveals a more CEA-like expression pattern. Northern blot analyses identified a 2.5-kilobase CGM2 mRNA that is strongly down-regulated in colonic adenocarcinomas compared with adjacent colonic mucosa, suggesting a possible tumor suppressor function. In addition, a 3.2- kilobase transcript was observed in a number of colon tumors that is not detectable in normal colonic tissue. This mRNA species could represent a tumor-specific CGM2 splice variant.

Carcinoembryonic antigen (CEA) is a tumor marker that belongs to a family of closely related molecules with variable expression patterns. We have developed sets of oligonucleotide primers for the specific amplification of transcripts from individual CEA-family members using the reverse transcriptase/ polymerase chain reaction (RT/PCR). Specific primer sets were designed for CEA, non-specific cross-reacting antigen (NCA), biliary glycoprotein (BGP), carcinoembryonic antigen gene-family members 1, 6 and 7 (CGMI, CGM6 and CGM7), and one set for all pregnancy-specific glycoprotein (PSG) transcripts. Primers were first tested for their specificity against individual cDNA clones and product-hybridization with internal, transcript-specific oligonucleotides. Total RNA from 12 brain and 63 gynecological tumors were then tested for expression of CEA-related transcripts. None were found in tumors located in the brain, including various mesenchymal and neuro-epithelial tumors. CEA and NCA transcripts were, however, present in an adenocarcinoma located in the nasal sinuses. In ovarian mucinous adenocarcinomas, we always found co-expression of CEA and NCA transcripts, and occasionally BGP mRNA. CEA-related transcripts were also found in some serous, endometrioid and clear-cell ovarian carcinomas. CEA, NCA and BGP transcripts were present in endometrial carcinomas of the uterus and cervical carcinomas, whereas uterine leiomyomas were completely negative. No transcripts were found from CGM 1, CGM6, CGM7 or from PSG genes in any of the tumors tested. The PCR data were compared with immunohistochemical investigations of ovarian tumors at the protein level using CEA (26/3/13)-, NCA-50/90 (9A6FR) and NCA-95 (80H3)-specific monoclonal antibodies.

The tumor marker carcinoembryonic antigen (CEA) belongs to a family of proteins which are composed of one immunogiobulin variable domain and a varying number of immunoglobulin constant-like domains. Most of the membrane-bound members, which are anchored either by a glycosylphosphatidylinositol moiety or a transmembrane domain, have been shown to convey cell adhesion in vitro. Here we describe two splice variants of CGMI. a transmembrane member of the CEA family without immunoglobulin constant.like domains. CGM1a and CGM1c contain cytopiasmic domains of 71 and 31 amino acids, respectively, The cytoplasmic region of CGM1a is encoded by four exons (Cyt1-Cyt4). Differential splicing of the Cyt1 exon (53 bp)...

The carcinoembryonic antigen (CEA) is a human tumor marker whose gene belongs to a family with more than 20 members. This gene family codes for a group of proteins with in vitro cell adhesion properties and for a group of abundantly expressed pregnancy-specific glycoproteins (PSG) with unknown functions. As a basis for in vivo functional studies, we have started to analyze the murine CEA gene family and have identified five new members (Cea-2 to Cea-6). cDNA clones were isolated for Cea-2, Cea-3, and Cea-6. The deduced amino acid sequences of Cea-2 and Cea-6 indicate three IgV-like (N), followed by one IgC-like (A) domain (N1-N2-N3-A). We have also partially characterized the Cea-2 gene and two additional ones, Cea-4 and Cea-5. Cea-2 and Cea-4 are separated by only 16 kb, suggesting a close linkage of murine CEA-related genes, as found for the human CEA gene family. Cea-5 was located to the proximal region of mouse Chromosome (Chr) 7, which is syntenic to part of human Chr 19, containing the human CEA gene family cluster. Cea-2, Cea-3, and a Cea-4-like gene are differentially transcribed in the placenta during pregnancy, but not in other organs tested. This expression pattern strongly suggests that they represent counterparts of the human PSG subgroup members, despite the presence of multiple IgV-like domains, a feature not found for human PSGs. The more distantly related Cea-5 seems to be ubiquitously expressed. The putative promoter region of Cea-2 lacks typical TATA-or CAAT-boxes, but contains other conserved motifs that could play a role in the initiation of transcription.

A long-range physical map of the carcinoembryonic antigen (CEA) gene family cluster, which is located on the long arm of chromosome 19, has been constructed. This was achieved by hybridization analysis of large DNA fragments separated by pulse-field gel electrophoresis and of DNA from human/rodent somatic cell hybrids, as well as the assembly of ordered sets of cosmids for this gene region into contigs. The different approaches yielded very similar results and indicate that the entire gene family is contained within a region located at position 19q13.1–q13.2 between the CYP2A and the D19S15/D19S8 markers. The physical linkage of nine genes belonging to the CEA subgroup and their location with respect to the pregnancy-specific glycoprotein (PSG) subgroup genes have been determined, and the latter are located closer to the telomere. From large groups of ordered cosmid clones, the identity of all known CEA subgroup genes has been confirmed either by hybridization using gene-specific probes or by DNA sequencing. These studies have identified a new member of the CEA subgroup (CGM8), which probably represents a pseudogene due to the existence of two stop codons, one in the leader and one in the N-terminal domain exons. The gene order and orientation, which were determined by hybridization with probes from the 5′ and 3′ regions of the genes, are as follows: cen/3′-CGM7-5′/3′-CGM2-5′/5′-CEA-3′/5′-NCA-3′/5′- CGM1-3′/3′-BGP-5′/3′-CGM9-5′/3′-CGM6-5′/5′-CGM8-3′/PSGcluster/qter.

We recently cloned members of the murine carcinoembryonic antigen (CEA) gene family, some of which are differentially expressed during placental development. By intra- and interspecies sequence comparisons, we identified an element in the putative promoter and/or 5′-nontranslated region which is conserved within all human and rodent CEA-related genes analyzed so far. Using gel retardation analysis and DNasel hypersensitive site mapping, we now show that ubiquitously expressed nuclear factors specifically bind to the conserved region derived from the mouse gene Cea-2 in vitro and probably also in vivo. Another DNasel hypersensitive site lies within or close to a simple sequence motif [(GGA)n] located in the first intron of Cea-2. Such sequences have been reported to play a role in the regulation of certain genes. Therefore, this analysis has identified putative regulatory regions for Cea-2 and possibly CEA-related genes in general.

The authors tried to differentiate malignancy-related from nonmalignant ascites with a sequence of sensitive followed by specific ascitic-fluid parameters. There were four results of this study. First, of nine parameters investigated in a first series of 48 patients, 28 with nonmalignant and 20 with malignancy-related ascites, ascitic-fluid cholesterol and fibronectin yielded the best negative predictive value of 92% each. Carcinoembryonic antigen (CEA) and cytologic examination both showed a positive predictive value of 100%. Second, combining cytologic examination (sensitivity, 70%) and CEA determination (sensitivity, 45%) increased the sensitivity to 80%. Third, cytologic findings were negative in all ascitic-fluid samples with a cholesterol concentration below the cutoff value of 45 mg/100 ml. Fourth, based on the results of the first series of 48 patients, the diagnostic sequence with cholesterol as a sensitive parameter, followed by the combination of cytologic examination and CEA determination as specific parameters, was tested in a second series of 71 patients, 37 with nonmalignant and 34 with malignancy-related ascites. Again cytologic examination was negative in all samples with cholesterol levels below 45 mg/100 ml. In the total of 119 patients, this diagnostic sequence did not identify 9% of patients with malignancy-related ascites, and 82% of samples classified as malignancy related by cholesterol levels above 45 mg/100 ml were confirmed by positive cytologic examination and/or CEA level above 2.5 ng/ml. Thus, a diagnostic sequence with ascitic-fluid cholesterol determination, followed by cytologic examination and CEA determination, in samples with cholesterol levels above 45 mg/100 ml should permit a cost-efficient routine differentiation of malignancy-related from nonmalignant ascites.

The carcinoembryonic antigen (CEA) gene family belongs to the immunoglobulin supergene family and can be divided into two main subgroups based on sequence comparisons. In humans it is clustered on the long arm of chromosome 19 and consists of approximately 20 genes. The CEA subgroup genes code for CEA and its classical crossreacting antigens, which are mainly membrane-bound, whereas the other subgroup genes encode the pregnancy-specific glycoproteins (PSG), which are secreted. Splice variants of individual genes and differential post-translational modifications of the resulting proteins, e.g., by glycosylation, indicate a high complexity in the number of putative CEA-related molecules. So far, only a limited number of CEA-related antigens in humans have been unequivocally assigned to a specific gene. Rodent CEA-related genes reveal a high sequence divergence and, in part, a completely different domain organization than the human CEA gene family, making it difficult to determine individual gene counterparts. However, rodent CEA-related genes can be assigned to human subgroups based on similarity of expression patterns, which is characteristic for the subgroups. Various functions have been determined for members of the CEA subgroup in vitro, including cell adhesion, bacterial binding, an accessory role for collagen binding or ecto-ATPases activity. Based on all that is known so far on its biology, the clinical outlook for the CEA family has been reassessed.

The carcinoembryonic antigen (CEA) gene family belongs to the immunoglobulin superfamily and can be subdivided into the CEA and pregnancy-specific glycoprotein subgroups. The basic structure of the encoded proteins consists of, in addition to a leader, one IgV-like and 2, 3, or 6 IgC-like domains. These domains are followed by varying COOH-terminal regions responsible for secretion, transmembrane anchoring, or insertion into the membrane by a glycosyl phosphatidylinositol tail. Here we report on the characterization of CGM6, a new member of the CEA gene subgroup, by complementary DNA cloning. The deduced coding region comprises 349 amino acids and consists of a leader, one IgV-like, two IgC-like domains, and a hydrophobic region, which is replaced by a glycosyl phosphatidylinositol moiety in the mature protein. CGM6 transcripts were only found thus far in leukocytes of chronic myeloid leukemia patients, in normal bone marrow, and in marginal amounts in normal granulocytes. The CGM6 gene product might, therefore, represent a myeloid marker. Analyses of CGM6 protein-expressing HeLa transfectants with monoclonal antibodies strongly indicate that the CGM6 gene codes for the CEA family member NCA-95.

Carcinoembryonic antigen (CEA) is a widely used tumor marker, especially in the surveillance of colonic cancer patients. Although CEA is also present in some normal tissues, it is apparently expressed at higher levels in tumorous tissues than in corresponding normal tissues. As a first step toward analyzing the regulation of expression of CEA at the transcriptional level, we have isolated and characterized a cosmid clone (cosCEA1), which contains the entire coding region of the CEA gene. A close correlation exists between the exon and deduced immunoglobulin-like domain borders. We have determined a cluster of transcriptional starts for CEA and the closely related nonspecific cross-reacting antigen (NCA) gene and have sequenced their putative promoters. Regions of sequence homology are found as far as approximately 500 nucleotides upstream from the translational starts of these genes, but farther upstream they diverge completely. In both cases we were unable to find classic TATA or CAAT boxes at their expected positions. To characterize the CEA and NCA promoters, we carried out transient transfection assays with promoter-indicator gene constructs in the CEA-producing adenocarcinoma cell line SW403, as well as in nonproducing HeLa cells. A CEA gene promoter construct, containing approximately 400 nucleotides upstream from the translational start, showed nine times higher activity in the SW403 than in the HeLa cell line. This indicates that cis-acting sequences which convey cell type-specific expression of the CEA gene are contained within this region.

Mon, 1 Jan 1990 12:00:00 +0100 https://epub.ub.uni-muenchen.de/7127/1/7127.pdf Zimmermann, Wolfgang; Barnett, T.

The gene encoding the human tumor marker carcinoembryonic antigen (CEA) belongs to a gene family which can be subdivided into the CEA and the pregnancy-specific glycoprotein subgroups. The corresponding proteins are members of the immunoglobulin superfamily, characterized through the presence of one IgV-like domain and a varying number of IgC-like domains. Since the function of the CEA family is not well understood, we decided to establish an animal model in the rat to study its tissue- specific and developmental stage-dependent expression. To this end, we have screened an 18-day rat placenta cDNA library with a recently isolated fragment of a rat CEA-related gene. Two overlapping clones containing the complete coding region for a putative 709 amino acid protein (rnCGM1; Mr = 78,310) have been characterized. In contrast to all members of the human CEA family, this rat CEA-related protein consists of five IgV-like domains and only one IgC-like domain. This novel structure, which has been confirmed at the genomic level might have important functional implications. Due to the rapid evolutionary divergence of the rat and human CEA gene families it is not possible to assign rnCGM1 to its human counterpart. However, the predominant expression of the rnCGM1 gene in the placenta suggests that it could be analogous to one of the human pregnancy-specific glycoprotein genes.

The pregnancy-specific glycoprotein (PSG) genes constitute a subgroup of the carcinoembryonic antigen (CEA) gene family. Here we report the cloning of four cDNAs coding for different members of the PSG family from a human fetal liver cDNA library. They are derived from three closely related genes (PSG1, PSG4 and PSG6). Two of the cDNA clones represent splice variants of PSG1 (PSG1a, PSG1d) differing in their C-terminal domain and 3′-untranslated regions. All encoded proteins show the same domain arrangement (N-RA1-RA2-RB2-C). Transcripts of the genes PSG1 and PSG4 could be detected in placenta by hybridization with gene-specific oligonucleotides. Expression of cDNA in a mouse and monkey cell line shows that the glycosylated PSG1a protein has a Mr of 65–66 kD and is released from the transfected cells. Sequence comparisons in the C-terminal domain and the 3′-untranslated regions of CEA/PSG-like genes suggests a complex splicing pattern to exist for various gene family members and a common evolutionary origin of these regions

Various rodent and primate DNAs exhibit a stronger intra- than interspecies cross-hybridization with probes derived from the N-terminal domain exons of human and rat carcinoembryonic antigen (CEA)-like genes. Southern analyses also reveal that the human and rat CEA gene families are of similar complexity. We counted at least 10 different genes per human haploid genome. In the rat, approximately seven to nine different N-terminal domain exons that presumably represent different genes appear to be present. We were able to assign the corresponding genomic restriction endonuclease fragments to already isolated CEA gene family members of both human and rat. Highly similar subgroups, as found within the human CEA gene family, seem to be absent from the rat genome. Hybridization with an intron probe from the human nonspecific cross-reacting antigen (NCA) gene and analysis of DNA sequence data indicate the conservation of noncoding regions among CEA-like genes within primates, implicating that whole gene units may have been duplicated. With the help of a computer program and by calculating the rate of synonymous substitutions, evolutionary trees have been derived. From this, we propose that an independent parallel evolution, leading to different CEA gene families, must have taken place in, at least, the primate and rodent orders.

Five members of the human CEA gene family [human pregnancy-specific β1-glycoprotein (PSβG), hsCGM1, 2, 3 and 4] have been isolated and identified through sequencing the exons containing their N-terminal domains. Sequence comparisons with published data for CEA and related molecules reveal the existence of highly-conserved gene subgroups within the CEA family. Together with published data eleven CEA family members have so far been determined. Apart from the highly conserved coding sequences, these genes also show strong sequence conservation in their introns, indicating a duplication of whole gene units during the evolution of the CEA gene family.

The existence of a carcinoembryonic antigen (CEA)-like gene family in rat has been demonstrated through isolation and sequencing of the N- terminal domain exons of presumably five discrete genes (rnCGM1-5). This finding will allow for the first time the study of functional and clinical aspects of the tumor marker CEA and related antigens in an animal model. Sequence comparison with the corresponding regions of members of the human CEA gene family revealed a relatively low similarity at the amino acid level, which indicates rapid divergence of the CEA gene family during evolution and explains the lack of cross- reactivity of rat CEA-like antigens with antibodies directed against human CEA. The N-terminal domains of the rat CEA-like proteins show structural similarity to immunoglobulin variable domains, including the presence of hypervariable regions, which points to a possible receptor function of the CEA family members. Although so far only one of the five rat CEA-like genes could be shown to be transcriptionally active, multiple mRNA species derived from other members of the rat CEA-like gene family have been found to be differentially expressed in rat placenta and liver.

Fri, 1 Jan 1988 12:00:00 +0100 https://epub.ub.uni-muenchen.de/5375/1/Zimmermann_Wolfgang_5375.pdf Thompson, John A.; Kleist, Sabine von; Shively, John E.; Fiebig, Heinz-Herbert; Schempp, Werner; Rudert, Fritz; Ortlieb, Barbara; Weber, Bernhard; Zimmermann, Wolfgang

The molecular cloning of carcinoembryonic antigen (CEA) and several cross-reacting antigens reveals a basic domain structure for the whole family, which shows structural similarities to the immunoglobulin superfamily. The CEA family consists of approximately 10 genes which are localized in two clusters on chromosome 19. So far, mRNA species for five of these genes have been identified which show tissue variability in their transcriptional activity. Expression of some of these genes in heterologous systems has been achieved, allowing the localization of some epitopes. The characterization of a CEA gene family in the rat and a comparison with its human counterpart has been utilized in the development of an evolutionary model.

Fri, 1 Jan 1988 12:00:00 +0100 https://epub.ub.uni-muenchen.de/5385/1/Zimmermann_Wolfgang_5385.pdf Shively, John E.; Riggs, Arthur D.; Hinoda, Yuji; Shively, Louise; Zimmermann, Wolfgang; Neumaier, Michael

For the isolation of cDNA clones encoding the carcinoembryonic antigen (CEA), we have constructed a cDNA library from human colon tumor mRNA. The library was screened with various oligonucleotides whose sequence had been deduced from partial amino acid sequence data for CEA. Positive candidate clones were hybridized with a probe for repetitive DNA, because CEA mRNA contains an Alu repetitive element, and with a fragment of a genomic clone of nonspecific cross-reacting antigen, an antigen closely related to CEA. Here we report the nucleotide sequence of the two overlapping CEA cDNA clones comprising 1422 nucleotides of CEA mRNA. This sequence encodes the 372 COOH-terminal amino acids of CEA followed by 305 nucleotides of 3' untranslated sequence containing a truncated Alu repeat. The predicted protein sequence is composed of two repeats comprising 178 amino acids, each with an exceptionally high homology of 67%. Each repeat unit contains four conserved cysteine residues and six to nine putative N-glycosylation sites. CEA mRNA is most strongly expressed in primary colon tumors and, to a lesser extent, in normal colonic tissue. No CEA mRNA is found in HeLa cells and normal human fibroblasts.