Human alpha-1-antitrypsin (AAT), the most abundant protease inhibitor found in the blood, was expressed in rice embryonic tissue suspension cell culture. This was accomplished by cloning the codon-optimized AAT gene into a vector containing the rice RAmy3D promoter and its signal sequence. The synthetic gene incorporates codons synonymous with those found in highly expressed rice genes. Approximately 1000 stable transformed calli were produced by particle bombardment mediated transformation and were screened for high AAT expression using a porcine elastase inhibitory activity assay. The band shift assay also confirmed that rice-derived AAT is functional regarding its binding capability to the elastase substrate. Time course studies were conducted to determine the optimum, postinduction expression levels from cell culture. AAT expression equivalent to 20% of the total secreted proteins was achieved, and a purification scheme was developed that yielded active AAT with purity greater than 95%. The potential applications of purified plant-derived AAT for treatments of various AAT-deficient diseases are discussed.

Animals↗

PubMedDate not supplied

Utilization of an alternative carbon source for efficient production of human alpha(1)-antitrypsin by genetically engineered rice cell culture.

Human alpha(1)-antitrypsin was produced by genetically engineered rice cells using promoter and signal peptide of a rice alpha-amylase isozyme. Batch and continuous cultures were employed to investigate the effects of alternative carbon sources on the alpha(1)-antitrypsin production. While this expression system is inducible by sugar depletion, we have found that the productivity of alpha(1)-antitrypsin increased 2.4- to 3.4-fold, compared with the control medium without carbon source, in medium containing an alternative carbon source, such as pyruvic acid and glyoxylic acid. The accumulated alpha(1)-antitrypsin in the medium containing pyruvic acid reached 18.2-24.2 mg/g-dry cell in 50-70 h by batch culture.

Carbon↗

PubMedDate not supplied

Sequential alteration of proto-oncogene expression in liver, spleen, kidney and brain of mice subjected to whole body irradiation.

Reverse transcription polymerase chain reaction (RT-PCR) was performed to evaluate the sequential alteration of proto-oncogene mRNA expression in liver, spleen, kidney and brain of mice after whole body irradiation (WBI). The mRNAs investigated in this study were Fas, c-fos, c-myc. bcl-2, and p53, and glyceraldehyde-3-phosphate dehydrogenase mRNA was employed as internal control. C3H/He mice aged 9-10 weeks were exposed to WBI of 7 Gy using a cobalt-60 teletherapy unit, without anesthesia, and sacrificed before and 0.1, 0.5, 1, 2, 3, 6, 12, 24, 48 and 96 h after irradiation. Their liver, spleen, kidney and brain were taken and immediately stored in liquid nitrogen until ready for RT-PCR. Each specimen was homogenized to extract RNA for conventional RT-PCR. The liver of mice administered 7 Gy of WBI revealed no significant changes in the expression of each of the mRNAs examined. In the spleen, c-fos mRNA expression decreased at 2 h following irradiation, and increased remarkably thereafter. In the kidney, no significant change in the expression of each mRNA was shown. In the brain c-fos mRNA expression decreased 1-24 h after irradiation, and showed a recovery thereafter. The remarkable differences in the sequential changes of c-fos mRNA expression following irradiation between each organ revealed by the present experiment may be an important aid in determining the tissue-specific radiosensitivity to ionizing radiation. Further investigations are, however, needed to clarify the signal transduction mechanisms which are mediated by the expression of these proto-oncogenes in each tissue following irradiation.

Animals↗

PubMedDate not supplied

ADP-ribosylation of myelin basic protein and inhibition of phospholipid vesicle aggregation.

Four isoforms of myelin basic protein (MBP) from chicken brain were ADP-ribosylated by chicken heterophil ADP-ribosyltransferase. The 21-kD isoform was the most preferential substrate of this transferase. With this isoform, the Km values were estimated to be 330 mumol/l for NAD and 30 mumol/l for MBP, and the optimal pH for ADP-ribosylation was 8.5. The stoichiometry of ADP-ribose incorporation into 21-kD MBP was 3.5 mol of ADP-ribose/mol MBP. We found the inhibition of ADP-ribosylation of MBP by hydroxylamine and L-arginine indicating that this modification was likely to be mediated by arginine residues. Proteolytic peptide maps of ADP-ribosylated MBP by chicken ADP-ribosyltransferase and cholera toxin showed partially different radio active bands. When 21-kD MBP was ADP-ribosylated by chicken transferase, the potential for phospholipid vesicle aggregation was reduced in proportion of the degree of ADP-ribosylation. The possibility that ADP-ribosylation of MBP may control stabilization of myelin through regulation of its affinity for phospholipid in vivo would need to be considered.

Adenosine Diphosphate Ribose↗

PubMedDate not supplied

Establishment and characterization of a new human extrahepatic bile duct carcinoma cell line (ICBD-1).

A new human extrahepatic bile duct carcinoma cell line (ICBD-1) was established from surgically resected tumor of a 71-year-old Japanese male patient. ICBD-1 cells proliferate in a layer with a population doubling time of 31.5 h and secrete tissue polypeptide antigen. ICBD-1 cells have a tetraploid pattern with a DNA index of 1.83 and chromosome counts showed equally distribution in a range from 65 to 69. IC50 values for ICBD-1 cells were 200 ng/ml for adriamycin, 400 ng/ml for mitomycin C, 2 microg/ml for cisplatin and 300 ng/ml for 5-fluorouracil. ICBD-1 cells were successfully transplanted to male nude mice, inducing progressive tumor growth. Histologically, nude mouse tumors were less differentiated than the original human tumor. Tumor cells showed alveolar structures with thin fibrous stroma, classified as poorly-differentiated adenocarcinoma. ICBD-1 is the fourth established cell line that originate from extrahepatic bile duct carcinoma and it will be applicable for the experimental studies of this disease.

Adenocarcinoma↗

PubMedDate not supplied

Carcinoembryonic antigen level in peritoneal washing is a prognostic factor in patients with gastric cancer.

This study was designed to evaluate the usefulness of carcinoembryonic antigen (CEA) and sialyl-Tn antigen (STN) levels in peritoneal washings in gastric cancer patients. At the time of laparotomy, peritoneal washings were collected from 96 gastric cancer patients and CEA and STN levels were determined. Patients with elevated CEA (100 ng/g protein) had a high incidence for peritoneal metastasis, lymph node metastasis and serosal invasion. In addition, prognosis in patients with high CEA level was significantly poorer than in those without it. The peritoneal CEA is a prognostic factor in patients with gastric cancer.

Adult↗

PubMedDate not supplied

Changes of mutant-type p53 expression in squamous cell carcinoma of the head and neck during radiation therapy and its clinical significance: comparison of an immunohistochemical method and PCR-SSCP assay.

P53 has been reported to be one of tumor suppressor genes that play a major role in signal transduction following many kinds of stresses, including ionizing radiation. Changes in p53 expression during radiation therapy in tumor tissues have not yet been reported. We determined whether radiotherapy changes p53 expression in human squamous cell carcinomas of the head and neck, and established the possible correlations between p53 expression and the therapeutic effects of radiation therapy. 30 patients with tumors of the oral cavity, oropharynx, and maxillary sinus were examined, and all the tumors were confirmed as squamous cell carcinomas. Biopsies were performed on the cancer tissues before treatment and at doses of 4, 10, and 20 Gy of radiotherapy, and the specimens were preserved in liquid nitrogen for further examination. Samples were immunohistochemically stained using streptoavidin-biotin peroxidase method and a monoclonal antibody against p53 (Ab-3, mutant type). For all the samples p53 PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) assays were performed. 14 of the 30 patients with squamous cell carcinomas showed expression of p53 in their tumor cells before and/or at 4 Gy or 10 Gy of radiotherapy. Eleven of the 14 tumors showed high radiosensitivity. Results of the p53 PCR-SSCP assays revealed mutations of p53 in 13 of 30 patients examined, and percentages of mutated p53 DNA varied at radiation doses of 4 Gy and 10 Gy. Ten of 12 patients with mutated p53 in their tumors showed decreased percentages of mutated p53 DNA during radiotherapy. The relationship between the immunohistochemical findings and the antitumor effect of a radiation dose of 20 Gy was examined on the correspondent hematoxylin-eosin sections. In patients whose p53 expressions in tumor cells were grades + or ++ or before radiotherapy and/or at 4 Gy of radiotherapy, the tumors responded significantly well to radiation therapy but the patients responded with significantly unfavorable clinical courses. The high radiosensitivity of squamous cell carcinomas in our samples could be explained by an overexpression of mutant type p53 in the tumor cells, and these mutant type p53-positive tumor cells possibly showed radioresponsiveness.

Adult↗

PubMedDate not supplied

Analysis of radiation pneumonitis and radiation-induced lung fibrosis in breast cancer patients after breast conservation treatment.

We examined radiation pneumonitis in breast cancer patients after breast conservation treatment (BCT) and analysed the degree of radiation-induced lung fibrosis by computed tomographies of the chest (chest CT). Fifty-two breast cancer patients were treated with BCT, including breast irradiation and chemotherapy. These patients symptomatic of radiation pneumonitis were examined every two to four weeks. Chest X-rays and chest CT were performed about one year after irradiation. symptoms due to radiation pneumonitis was registered in 9.6% of patients. lungs showed fibrotic changes by chest CT in 90% of the cases. Concurrent or alternative chemotherapy increased the incidence of symptomatic radiation pneumonitis and, to a certain extent, the degree of fibrotic change in the lung after BCT.

Adult↗

PubMedDate not supplied

Conservation treatment intensified with tamoxifen and CAF chemotherapy without axillary dissection for early breast cancer patients with clinically-negative axillary nodes.

Axillary node dissection has been a routine part of breast cancer treatment for more than 100 years. As so few patients have been shown to have positive nodes, more consideration should be given to eliminating axillary node dissection for duct carcinoma in situ (DCIS) and T1a lesions. And for patients with a T1/2N0M0 cancer of the breast, lumpectomy alone without axillary dissection followed by radiation therapy to the intact breast and regional lymph nodes should be a reasonable treatment method that avoids arm morbidity. Between September 1989 and December 1998, we treated 79 breast cancer patients with this method intensified with tamoxifen and CAF chemotherapy. Before the start of the therapy, we performed a thorough evaluation using helical CT and doppler ultrasonography to exclude patients with significant swelling of axillary lymph nodes (more than 5 mm in short diameter). Through the end of December 1998, the mean follow-up period was 52.6 months. Up to this date, only one patient of the 79 showed local recurrence within 5 years after the start of the treatment. This patient received a second lumpectomy. She then experienced lung metastases 6 months later. She is currently receiving combined chemotherapy with docetaxel and cisplatin. The cause-specific survival rate of these 79 patients maintained 100% at 6 years, and no axillary failure has been experienced so far. The cosmetic results in 50 (65.8%) of the 76 patients who were alive at the end of December 1998 were rated as excellent, 26 (34.2%) as good, and none as fair or poor. Therefore, we have concluded that this method of treatment for early breast cancer could eliminate surgical damage and allow good cosmetic results, and that survival rates with this treatment are excellent.

Adult↗

PubMedDate not supplied

Conservation treatment intensified with an anti-estrogen agent and CAF chemotherapy for stage I and II breast cancer.

In order to improve both cosmetic results and survival rates, we performed breast-conservation treatment (BCT) intensified with tamoxifen and CAF chemotherapy to 218 out of 224 patients who visited our department with the desire of breast-conservation between August 1989 to December 1998. Of these patients, 68 presented with tumors of stage I, and another 122 stage II. All patients were administered tamoxifen (for pre-menopausal women) or tremifene (for post-menopausal women) orally: tamoxifen and tremifene administration was started just after confirmation of the breast cancer based on the findings of fine-needle aspiration cytology. All patients underwent lumpectomy with or without axillary dissection (level I and II). For patients with T2 tumors, the lumpectomy was performed following two to four times of CAF chemotherapy. Following conservative surgery, patients were treated with radiation therapy to the intact breast and ipsilateral axilla to a total dose of 4400 cGy with a conedown to a total median dose of 5300 cGy. At the end of March 1999, the mean follow-up time was 49.0 months. In spite of high-positivity (approximately 30%) of microscopically surgical margin, local recurrence rate is considerably low, and only 2 patients experienced local recurrence. Cause-specific survival rate for patients of stage I is 100%, and that of stage II is 91.7% at 5 years. The cosmetic results of therapy were also considered good.

Adult↗