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Biomedical subjects

S Hojo

Publications and source records attributed to S Hojo.

At least 19 recordsLinked to original sources
PubMed2006

Spontaneous rupture of sacrococcygeal teratoma associated with acute fetal anemia.

Sacrococcygeal teratoma (SCT) is the most common congenital tumor, with affected fetuses having a high risk of perinatal complications and death. We report a case of a fetus with an SCT that developed acute anemia due to spontaneous rupture of the tumor in utero. The fetus was referred at 25 weeks' gestation for evaluation of a large solid and cystic mass in the sacral region. There were no signs of hydrops or placentomegaly. At 33 weeks' gestation, loss of variability in the fetal heart rate pattern was recorded. Doppler ultrasonography showed increased middle cerebral artery peak systolic velocity, suggesting fetal anemia. Markedly bloody amniotic fluid, with 82% hemoglobin F, was observed on amniocentesis, suggesting rupture of the SCT with active fetal bleeding. An emergency Cesarean section was performed. At delivery, the tumor was bleeding actively and the neonatal hemoglobin concentration was 3.1 g/dL. There were no findings of hemorrhage or necrosis within the tumor. The neonate received a blood transfusion, and surgical resection of the tumor was carried out on the first day after delivery. Postoperatively, the baby did well. We suggest that fetal SCTs run the risk of inducing acute fetal anemia due to intrauterine hemorrhage of the tumor, a finding which could lead to an earlier and more appropriate management of this condition.

Acute Disease↗
PubMed2001

The role of caspase 3 in producing cytokeratin 19 fragment (CYFRA21-1) in human lung cancer cell lines.

The CYFRA 21-1 assay, which detects cytokeratin 19 (CK19) fragment, is widely used as a tumor marker for lung cancer, particularly non-small cell lung cancer. However, the reason that some lung cancer cell lines release CYFRA 21-1 in culture supernatants and others do not remains unclear. We hypothesized that the release of CYFRA 21-1 might be related to the expression of CK19 and caspase 3. In order to prove this, the quantities of mRNA for CK19 were evaluated by the competitive reverse transcriptase-polymerase chain reaction (RT-PCR). CK19 protein synthesis was also evaluated by Western blotting and immunohistochemistry, and the levels of CYFRA 21-1 in the culture supernatant were measured by an immunoradiometric assay. The expression of mRNA for caspase 3 was evaluated by the RT-PCR, and caspase 3 protein synthesis was also evaluated by immunohistochemistry. In 13 lung cancer cell lines, the amounts of mRNA for CK19 correlated with the levels of CYFRA 21-1 in culture supernatants, results of Western blotting for CK19, and positivities of immunohistochemistry for CK19. In 5 cell lines that produced a significant amount of CYFRA 21-1, the level of CYFRA 21-1 correlated with the positivity of RT-PCR for caspase 3 and immunohistochmistry for caspase 3. This suggests that caspase 3 played a role in the formation of CYFRA 21-1. In addition, the specific inhibitor of caspase 3 significantly inhibited the release of CYFRA 21-1 in culture supernatants. In conclusion, we demonstrate that caspase 3, which cleaves several intermediate filaments and carries out cell apoptosis, played an important role in producing CYFRA 21-1 in human lung cancer cell lines.

Animals↗
PubMed2001

Primary lung cancer associated with polymyositis/dermatomyositis, with a review of the literature.

It has been suggested that lung cancer is frequently associated with polymyositis/dermatomyositis (PM/DM). The purpose of this study was to describe the clinical features of primary lung cancer associated with PM/DM. We first describe the clinical features of two cases treated in our hospital, and then provide a review of the literature. Finally, 24 patients (five females and 19 males) with primary lung cancer associated with PM/DM are retrospectively evaluated. Histological types of lung cancer were as follows: small cell lung cancer (n = 7), squamous cell carcinoma (n = 5), adenocarcinoma (n = 2), others (n = 5), and unknown (4). The onset of PM/DM is frequently observed before the detection of lung cancer. This is the first report to describe the clinical features of lung cancer associated with PM/DM.

Adult↗
PubMed2001

The point mutation in the promoter region and the single nucleotide polymorphism in exon 1 of the cytokeratin 19 gene in human lung cancer cell lines.

The CYFRA 21-1 assay which detects the cytokeratin 19 (CK19) fragment is widely used as a tumor marker for lung cancer. We previously suggested that the failure of PCR amplification of exon 1 is closely related to the inability of the expression of mRNA for CK19, and hypothesized that point mutations might exist within exon 1. In order to prove this, sequence analysis of the promoter region and exon 1 was performed in 14 human lung cancer cell lines. Among the 14 lung cancer cell lines evaluated, point mutations within the promoter region (at -99, G-->C) of the CK19 gene were demonstrated in two cell lines (Lu135 and HI1017). In addition, point mutations within exon 1 (at 90, T-->C, Ala-->Ala and at 179, G-->C, Gly-->Ala) were also demonstrated in three cell lines (LU135, HI1017, and LC2/AD). Point mutations within the promoter region of CK19 (at -99) and within exon 1 (at 179) were confirmed by analysis of digestion by specific restriction enzymes. Since the same point mutation within exon 1 (at 179) was observed in genomes of normal volunteers, this mutation was considered as a single nucleotide polymorphism. In contrast, there were no mutations within the promoter region of exon 1 in genomes of normal volunteers. After a computer search, it was demonstrated that several transcription factors bind to the sense primer sequence which was designed for amplification of exon 1. In addition, after point mutations within the promoter region occurred (at -99), new sequences appeared to which known transcription factors (AP2) bind. In conclusion, analysis of genomic DNA for CK19 suggested that expression of mRNA for CK19 was regulated by several transcription factors which bound to the specific sequence with the promoter region of the CK19 gene. It was also suggested that the mutation in the promoter region of the CK19 gene down-regulated the expression of mRNA for CK19.

Antigens, Neoplasm↗
PubMed2001

Anti-cytokeratin antibodies in sera of the patients with autoimmune hepatitis.

Antibodies to cytokeratin (CK) are found in some patients with autoimmune hepatitis (AIH). We hypothesized that serum antibodies to CK8, CK18 and CK19 may be formed in patients with AIH. We established an enzyme-linked immunosorbent assay (ELISA) to quantify anti-CK8, anti-CK18 and anti-CK19 antibodies in sera of patients with AIH. In addition, we quantified circulating CK8:anti-CK8 antibody as well as CK18:anti-CK18 antibody immune complexes in patients' sera, by an enzyme-linked immunosorbent assay (ELISA). Furthermore, to evaluate the expression of CK8, CK18 and CK19 in liver tissue, immunohistochemical stainings were performed. Significantly high levels of anti-CK8, anti-CK18 and anti-CK19 antibodies were demonstrated in patients with AIH compared with normal volunteers and patients with chronic active hepatitis C (CH-C). In addition, these antibodies were significantly decreased after steroid treatment. Levels of CK8:anti-CK8 and CK18:anti-CK18 immune complexes in sera of patients with AIH were significantly high compared with those of patients with CH-C and normal volunteers. Immunohistochemically, CK8 or CK18 were absent from some hepatocytes of AIH. CK19 was aberrantly expressed in periportal hepatocytes in patients with AIH, but not CH-C. This is the first study to quantify anti-CK8, anti-CK18, anti-CK19 antibodies and immune complexes in patients with AIH. The clinical significance of anti-CK antibodies and their immune complexes of AIH is also discussed.

Adolescent↗
PubMed2001

Retention of maxillary implant overdenture bars of different designs.

STATEMENT OF PROBLEM: The specific degree of retention for overdenture attachments is unknown in relation to design, location, and alignment to supporting dental implants. PURPOSE: The purpose of this study was to evaluate the initial retention characteristics of 5 implant maxillary overdenture designs under in vitro dislodging forces. MATERIAL AND METHODS: A simulated edentulous maxilla was fabricated with 4 screw-type 3.75 x 13-mm implants anteriorly. Five overdenture designs with the following attachments were evaluated: 4 plastic Hader clips with an EDS bar; 2 plastic anterior Hader clips with an identical EDS bar; 2 Hader clips with 2 posterior ERA attachments; 3 Zaag attachments on a bar; and 4 Zaag attachments with no bar. Overdentures were fabricated with full palatal coverage. Each design was subjected to 10 consecutive retention pulls on a universal testing machine. Data were subjected to analysis of variance and t tests to determine differences. RESULTS: The highest average value after 10 pulls was 19.8 lb for the combination ERA and Hader clip design. The lowest retentive values were recorded for the 2 and 4 Hader clip designs (5.08 +/- 0.89 lb and 5.06 +/- 0.67 lb, respectively). Retention decreased over the course of consecutive pulls for all designs, especially for the most retentive designs. The smallest retention decrease occurred with the least retentive designs. CONCLUSION: The results of this in vitro study suggest that the precise selection and placement of attachments may affect the clinical success of maxillary implant-retained overdentures.

Dental Clasps↗
PubMed2001

Expression of carcinoembryonic antigen in peripheral- or central-located small cell lung cancer: its clinical significance.

BACKGROUND: Small cell lung cancer (SCLC) has a higher percentage of hilar masses than other histological types of lung cancer. The primary site is usually adjacent to the hilum, but we often observe primary sites in the peripheral lung field. In this study, our objectives were to elucidate whether peripheral-located small cell lung cancer (PSCLC) is an independent entity and whether it differs clinically from central-located small cell lung cancer (CSCLC). METHODS: We reviewed the clinical and pathological features of 52 patients treated at Kagawa Medical University Hospital between 1987 and 1996 with a diagnosis of SCLC. We defined CSCLC as a tumor whose primary site is located in the segmental bronchi or more proximally and PSCLC as a tumor located distal to the subsegmental bronchi. Twenty-one PSCLC patients and 31 CSCLC patients were identified. Kaplan-Meier survival curves were constructed and comparisons were made between PSCLC and CSCLC by the log-rank test. The carcinoembryonic antigen (CEA) level was also evaluated in each group. RESULTS: Although the percentage of limited disease (LD) in the patients with PSCLC was higher than that in the patients with CSCLC, the 3-year survival rate of PSCLC tended to be worse than that of CSCLC (9% for patients with PSCLC and 29% for those with CSCLC). Survival curves of patients with PSCLC also tended to be worse than those of patients with CSCLC, not only in the limited disease group but also in the extensive disease (ED) group. In addition, the mean CEA value in patients with PSCLC was higher than that in patients with CSCLC (p < 0.001), whereas the neuron specific enolase (NSE) level was not significantly different between PSCLC and CSCLC. The median survival of patients with pretherapeutic CEA titers of > or =5 ng/ml was significantly shorter than that in patients with CEA levels <5 ng/ml. CONCLUSION: These findings suggest that the survival of SCLC patients with a high CEA level was significantly shorter than that of patients with a low CEA level. In addition, CEA levels in PSCLC patients were significantly higher than those in CSCLC patients. However, the survivals of LD or ED patients with PSCLC and CSCLC were not statistically different.

Adenocarcinoma↗
PubMed2001

Elevation of cytokeratin 19 fragment in serum in patients with hepatoma: its clinical significance.

OBJECTIVES: Cytokeratin 19 fragment (CK19) levels in serum have already been documented as a useful tumour marker for lung cancer. In the present study, we hypothesize that CK19 may be increased in serum from patients with hepatoma. METHODS: We measured the CK19 levels in serum from patients with hepatoma and evaluated the correlation between CK19 level and each clinical parameter. We studied 70 patients diagnosed with hepatoma, and used 14 patients with chronic hepatitis C and 45 patients with liver cirrhosis as controls. RESULTS: In 33 of 70 patients (47.1%) with hepatoma, the serum CK19 level was elevated to above the normal range. CK19 levels in serum from patients with hepatoma were significantly correlated with levels of alpha-fetoprotein and prothrombin induced by vitamin K absence for factor II (PIVKA-II). In 57 patients with hepatoma in whom both CK19 and alpha-fetoprotein were measured, only CK19 was elevated in seven patients (12.3%). Immunohistochemical studies using hepatoma tissues demonstrated that hepatoma cells were stained by anti-human CK19 antibody. We also demonstrated that the HepG2 cell line expressed CK1 9. CONCLUSIONS: Our data demonstrate that hepatomas aberrantly express CK19, and that measurement of CK19 might be a useful tumour marker in diagnosing hepatoma.

Adult↗
PubMed2001

[A case of malignant pericardial effusion due to breast cancer successfully controlled by intrapericardial chemotherapy using pirarubicin].

We report a case of malignant pericardial effusion due to breast cancer that was successfully controlled by intrapericardial chemotherapy using pirarubicin. A 53-year-old woman underwent breast conserving therapy for left breast cancer in 1996. She was given CAF therapy and UFT as adjuvant therapy. Three years and 10 months after operation, she had malignant pericardial and pleural effusion. Pericardiocentesis and pleurocentesis were performed immediately. Pericardial effusion relapsed after some time and she was treated with intrapericardial chemotherapy using pirarubicin. After this treatment she has not suffered from pericardial effusion for 1 year and 4 months to date. This case suggests that intrapericardial chemotherapy is effective for malignant pericardial effusion.

Adenocarcinoma↗
PubMed2000

Mechanisms of the release of CYFRA21-1 in human lung cancer cell lines.

The CYFRA 21-1 assay which detects cytokeratin 19 (CK19) fragment is widely used as a tumor marker for lung cancer. However, the reason why some lung cancer cell lines release CK19 fragment in culture supernatants and others do not, remains unclear. It was hypothesized that the release of CK19 fragment may be elucidated by the expression of mRNA for CK19. In order to prove this, the mRNA for CK19 was quantitatively evaluated by the competitive reverse transcriptase-polymerase chain reaction (competitive RT-PCR). The level of CYFRA 21-1 in the culture supernatant was measured by an immunoradiometric assay. CK19 protein synthesis was evaluated by a Western blotting and immunohistochemistry. Fourteen lung cancer cell lines were evaluated, and the amount of mRNA correlated well with the level of CYFRA 21-1 in culture supernatants. Analysis of genomic DNA for CK19 demonstrated that three cell lines which could not produce CYFRA 21-1, conjectured that some abnormalities in exon 1 or the 5'-region upstream from exon 1. In conclusion, it was demonstrated that the release of CK19 fragment was closely related to the expression of mRNA for CK19, and the possibility that genomic change of CK19 DNA down-regulated the expression of mRNA for CK19 was suggested.

Antigens, Neoplasm↗
PubMed2000

Circulating bronchoepithelial cells expressing mRNA for surfactant protein A in patients with pulmonary fibrosis.

There are several unsolved clinical findings in patients with idiopathic pulmonary fibrosis (IPF); (i) predominance of fibrosis in the lower lung fields, (ii) digital clubbing, and (iii) patchy distribution of pulmonary fibrosis. To explain these unsolved problems, we hypothesized that regenerated or premature bronchoepithelial cells may circulate in the blood in patients with IPF. To prove this, we performed the reverse transcriptase-polymerase chain reaction (RT-PCR) for cytokeratin 19 (CK19) and pulmonary surfactant protein A (SPA) in peripheral blood in patients with IPF and pulmonary fibrosis associated with collagen vascular disorders. In addition, 20 patients with chronic pulmonary emphysema as a disease control and 19 normal volunteers were also evaluated for the existence of circulating bronchoepithelial cells. RT-PCR analysis showed that CK19 was expressed in 12 of 38 blood samples (31.6%) of IPF and pulmonary fibrosis associated with collagen vascular disorders, seven of 20 (35.0%) blood samples of chronic pulmonary emphysema, and four of 19 (21.1%) blood samples of normal volunteers. mRNA for SPA was positive in eight of 38 (21.1%) blood samples of IPF. In contrast, SPA expressing cells were not detected in any blood samples obtained from patients with chronic pulmonary emphysema or normal volunteers. This evidence suggests that there were some circulating bronchoepithelial cells expressing mRNA for SPA in peripheral blood of patients with IPF and pulmonary fibrosis associated with collagen vascular disorders.

Adult↗
PubMed2000

Effect of JTP-2942, a novel thyrotropin-releasing hormone analog, on motor deficits after chronic focal cerebral ischemia in rats.

To investigate the chronic effects of a novel thyrotropin-releasing hormone analog, JTP-2942 (N(alpha)-[(1S, 2R)-2-methyl-4-oxocyclopentylcarbonyl]-L-histidyl-L-prolinamide monohydrate), on behavioral changes after stroke, the authors examined its effects on motor and neurologic deficits using a middle cerebral artery (MCA) occlusion model in rats. A left MCA was permanently occluded at a proximal site. From 1 week after occlusion, JTP-2942 was intravenously administered once a day for 4 weeks. Sensorimotor performance was evaluated weekly for 10 weeks after the occlusion. The ability of the rat to maintain its body position on an inclined plane and neurologic examination based on hemiparesis and abnormal posture were examined. After all behavioral examinations were completed, the degree of shrinkage of the left hemisphere was measured. The ability of MCA-occluded rats to maintain body position on an inclined plane in the left-headed position was significantly lower than that of sham-operated rats throughout the test period. JTP-2942 gradually improved this deficit dose dependently, and a dose of 0.03 mg/kg of JTP-2942 significantly improved performance to the levels of the sham-operated rats. Neurologic deficits were also observed in MCA-occluded rats. JTP-2942 also significantly improved these deficits dose dependently. On the other hand, CDP-choline (500 mg/kg, administered intravenously), a therapeutic agent for the disturbance of consciousness and hemiparesis after stroke, improved neurologic deficits but did not affect the motor deficits measured using the inclined plane. It is noteworthy that the effects of JTP-2942 on these deficits were observed 4 weeks after cessation of drug administration. Furthermore, there was no difference in the degree of shrinkage of the cerebrum among the MCA-occluded groups. In the present study, long-lasting improving effects of JTP-2942 on the impairment of motor and neurologic functions were observed in rats with MCA occlusion, which continued after cessation of drug administration and which were not attributable to a reduction in ipsilateral cerebral shrinkage. It is considered that the effect of JTP-2942 on functional recovery is attributable to the activation of substitutive functions such as neuronal reconstruction. These pharmacologic properties of JTP-2942 may be of interest for the treatment of patients with motor and neurologic deficits during the chronic or subacute phase of stroke.

Animals↗
PubMed2000

Sequential changes of KL-6 in sera of patients with interstitial pneumonia associated with polymyositis/dermatomyositis.

OBJECTIVE: KL-6 is a mucin-like high molecular weight glycoprotein, which is strongly expressed on type II alveolar pneumocytes and bronchiolar epithelial cells. It has been demonstrated that the KL-6 antigen is a useful marker for estimating the activity of interstitial pneumonia. In this study, it is hypothesised that serum KL-6 is a useful marker to evaluate the activity of interstitial pneumonia associated with polymyositis/dermatomyositis (PM/DM). METHODS: KL-6 was measured in sera in 16 patients diagnosed with PM/DM. Five had non-specific interstitial pneumonia (NSIP), three had diffuse alveolar damage (DAD), and eight had no pulmonary involvement, and 10 were normal non-smokers as a control group. The correlation was also evaluated between the KL-6 level and each clinical course in patients with pulmonary involvement associated with PM/DM. Immunohistochemical analysis using monoclonal anti-KL-6 antibody was also performed. RESULTS: KL-6 concentrations in sera of patients with interstitial pneumonia associated with PM/DM were significantly high compared with those of PM/DM without interstitial pneumonia, and normal non-smokers. KL-6 concentrations in sera in patients with DAD significantly increased compared with those of other groups. KL-6 values in sera changed according to the progression or improvement of interstitial pneumonia. Immunohistochemical study using pulmonary tissues obtained from patients with DAD demonstrated that the hyaline membrane, proliferating type II pneumocytes, bronchial epithelial cells and some endothelial cells in pulmonary veins were stained by antihuman KL-6 antibody. CONCLUSION: These data demonstrate that measurement of serum KL-6 was a useful marker to evaluate the activity of acute interstitial pneumonia associated with PM/DM.

Acute Disease↗
PubMed2000

Role of carbohydrate antigens sialyl Lewis (a) (CA19-9) in bronchoalveolar lavage in patients with pulmonary fibrosis.

BACKGROUND: It has been reported that carbohydrate antigen sialyl Lewis (a) (CA19-9) levels are elevated in serum as well as in bronchoalveolar lavage fluid (BALF) of patients with pulmonary fibrosis. However, the biological significance of CA19-9 is unclear. OBJECTIVE: The purpose of the present study was to evaluate correlations between CA19-9 levels in BALF and several biochemical as well as clinical parameters in patients with pulmonary fibrosis. In addition, biological functions of CA19-9 were also examined. METHODS: We studied 24 patients with a diagnosis of pulmonary fibrosis: 16 with idiopathic pulmonary fibrosis (IPF) and 8 with pulmonary fibrosis associated with a collagen vascular disorder (PF-CVD). In BALF, carbohydrate antigens sialyl Lewis (a) (CA19-9), elastase: alpha(1)-proteinase inhibitor complex (E-PI), hepatocyte growth factor (HGF), LDH, IgG, IgA, albumin, and cell differentiation were measured. We also evaluated the effects of CA19-9 on neutrophil functions. RESULTS: CA19-9/albumin levels in BALF significantly correlated with HGF/albumin, elastase/albumin, LDH/albumin, total number of alveolar macrophages, and total number of neutrophils. Purified CA19-9 had a chemotactic activity for neutrophils. In addition, neutrophil chemotactic activity to C5a, fMLP, and interleukin 8 was significantly stimulated after incubation with purified CA19-9. Furthermore, CA19-9 increased the expression of CD15s on neutrophils. CONCLUSIONS: Our data demonstrated (i) CA19-9 in BALF correlated with other markers of inflammation in pulmonary fibrosis, and (ii) CA19-9 can modify neutrophil functions. These results suggest that CA19-9 may play a role in the process of lung injury in patients with pulmonary fibrosis.

Adult↗
PubMed2000

Circulating cytokeratin 8:anti-cytokeratin 8 antibody immune complexes in sera of patients with pulmonary fibrosis.

BACKGROUND: It has been suggested that the humoral immune system plays a role in the pathogenesis of idiopathic pulmonary fibrosis (IPF) and pulmonary fibrosis associated with collagen vascular disorders (PF-CVD). Although circulating immune complexes in patients' sera have been suggested, none of the antigens have been characterized. OBJECTIVES: The purpose of this study is to characterize the antigen of the immune complexes in patients' sera of pulmonary fibrosis. METHODS: As we previously established that one of the antibodies against A549 cells (lung alveolar type II cells) was anti-cytokeratin 8 (CK8), we confirmed the existence of anti-CK8 antibody in patients' sera by Western immunoblot. In addition, we tried to demonstrate circulating CK8:anti-CK8 immune complexes in patients' sera by Western immunoblot. Furthermore, we established an enzyme-linked immunosorbent assay to quantitate CK8:anti-CK8 immune complexes. RESULTS: In patients with pulmonary fibrosis, anti-CK8 antibodies were clearly demonstrated in sera by Western immunoblot. In addition, circulating CK8:anti-CK8 immune complexes were also clearly demonstrated by Western immunoblot. It was possible to establish ELISA to quantitate CK8:anti-CK8 immune complexes. If the cutoff value, which was determined based on the highest value of normal volunteers, was introduced, high CK8:anti-CK8 antibody complexes were demonstrated in 9 of 31 patients (29.0%) with IPF and PF-CVD. CONCLUSIONS: This is the first study to clarify the antigen of the circulating immune complex in sera of patients with IPF. These results suggest that circulating CK8:anti-CK8 immune complexes may have played a role in the process of lung injury in pulmonary fibrosis.

Aged↗
PubMed2000

Binding of recombinant human cytokeratin 19 to laminin: a possible role in interaction between intermediate filament derived from epithelial cells and extracellular matrixes.

Cytokeratin 8 (CK8) and cytokeratin 19 (CK19) is a specific cytoskeletal component of simple epithelia, including bronchial epithelial cells. We hypothesized that CK8 or CK19 released from epithelial cells may bind to and cause damage to extracellular matrixes through binding of anti-CK8 or anti-CK19 autoantibodies. In the present study, bindings of recombinant human CK8 and CK19 to laminin (both derived from mouse sarcoma cells and human), collagen, gelatin, and fibronectin were evaluated by a modified enzyme-linked immunosorbent assay (ELISA). In addition, binding of CK19 to laminin was also confirmed by inhibition assay. As a result, CK19 strongly bound to mouse laminin as well as human laminin. Pretreatment with laminin significantly reduced the binding of CK19 to laminin. However, binding of recombinant CK19 to laminin was not demonstrated by Western immunoblot, suggesting that SDS treatment of laminin diminished the binding. These results suggest that released CK19 from epithelial cells may have played a role in the damage of basement membrane by accumulation of an immune complex composed by CK19 and anti-CK19 autoantibody.

Animals↗
PubMed1999

Expression of cytokeratin 19 mRNA in human lung cancer cell lines.

The present study was designed to clarify the mechanism by which some lung cancer cell lines can produce cytokeratin 19 (CK19) fragment and others cannot. We hypothesized that some lung cancer cell lines which cannot release CK19 express an incomplete sequence of CK19 mRNA. Expression of mRNA was evaluated by RT-PCR using several primer pairs for CK19. CK19 in the culture supernatant was measured by an immuno-radiometric assay. CK19 protein synthesis was evaluated by Western immunoblot and immunohistochemistry. Among 16 lung cancer cell lines, 7 released significant amounts of CK19 in the supernatant. In some cell lines, expression of CK19 mRNA was observed only in some combinations of primers, suggesting that incomplete mRNA was expressed. 3'-RACE analysis detected amplified products of a shorter size compared with normal amplified products in cell lines which expressed incomplete CK19 mRNA, suggesting that 3'-ends of mRNA for CK19 were deleted. Results of Western immunoblot and immuno-histochemical staining using anti-human CK19 monoclonal antibody completely correlated with the results on CK19 levels in culture supernatants as well as with complete expression of mRNA. We conclude that levels of CK19 closely relate to the expression of complete mRNA for CK19.

Adenocarcinoma↗