Elucidation of the thermal stability of the neutral proteinase II from Aspergillus oryzae.

The neutral proteinase II from Aspergillus oryzae (NpII) is a zinc proteinase with three intramolecular disulfide bonds. NpII is most unstable after 10 min at about 75 degrees C, but regains stability beyond this temperature and is relatively stable at 100 degrees C. We analyzed the thermal stability of wild-type NpII and apo NpII. The results suggested that NpII unfolds reversibly upon incubation up to 100 degrees C, and that the irreversible inactivation observed is mainly due to autoproteolysis. To further understand the stability, a mutant NpII (Cys78-->Ala) lacking one of the disulfide bonds, was produced in a heterologous yeast expression system. The mutant NpII showed a similar stability profile, but the most unstable temperature and the most catalytically active temperature decreased to the same extent (around 10 degrees C), confirming that autoproteolysis is the main cause of the irreversible inactivation. Several lines of evidence presented in this study demonstrated that the thermal stability of o++NpII is attributed to reversible thermal unfolding and autoproteolysis.

Bilateral middle ear squamous cell carcinoma and clinical review of an additional 5 cases of middle ear carcinomas.

We reported a retrospective review of the clinical records for a 64 year old male patient with bilateral middle ear squamous cell carcinoma (MESCC), and for the five other patients with MESCC treated at our institution during the last 20 years. The patient with bilateral MESCC has survived and remained tumor free for more than 1.5 years after extended radical resection of the secondary tumor combined with intra-arterial and systemic chemotherapy, radiotherapy and immunotherapy. Four patients with unilateral MESCC were treated with multidisciplinary treatment (induction chemotherapy, surgery and radiotherapy), and the remaining patient was treated with radiotherapy and mastoidectomy. Five of the six patients are alive with no evidence of disease. The patient treated with radiotherapy and radical mastoidectomy died of local recurrence 3 years after diagnosis. We suggest that MESCC should be considered when refractory granulation, long-standing otorrhea, otalgia and facial paralysis are observed. Multidisciplinary treatment, including intra-arterial chemotherapy and en bloc resection of the temporal tumor is useful for the treatment of MESCC and will improve the prognosis of patients with this disease.

[Combined immuno-radio-chemotherapy of head and neck non-Hodgkin's lymphoma].

Twenty-one previously untreated cases, who underwent the same protocol at our department from January 1984 until December 1986, were investigated. The following results were obtained. Non-Hodgkin's lymphoma accounted for 10.5% of all the head and neck malignant tumors at our department. The age range was from 23 to 76 years of age and had a peak in the forties. Fourteen were male and seven were female. According to the stage distribution, six cases were stage I (28.6%), nine were stage II (42.9%), four were stage III (19.0%) and two were stage IV (9.5%). Stage I and II accounted for 71.4%. By site grouping, palatine tonsil and nasal cavity accounted for 38.1%, respectively. Surgical therapy was presumably useful for a solitary lesion which resisted all conservative therapies. By combined therapy with radiotherapy, VAPE-Chemotherapy and OK-432-immunotherapy, the survival rates were 100% (stage I), 77.8% (Stage II), 50% (stage III) and 50% (stage IV). The mean survival rate was 76.2%.

[Tissue and serum levels of 5-FU in the patients with head and neck malignant tumors--influence of a streptococcal preparation OK-432].

Concentrations of Tegafur, 5-FU, and Uracil were measured in the tissues and serum of 32 patients with malignant head and neck tumors after administration of UFT or UFT and OK-432. Of the 32 patients, 15 patients were treated with UFT alone and 17 patients with a combination of UFT and a clinical dose of OK-432. The level of 5-FU was higher in the tissues and serum in the patients who received the combined administration of UFT and OK-432 than in those the received UFT alone. In particular, levels of 5-FU in tumor tissue and metastatic lymph node tissue were higher than 0.05 micrograms/g even 14.6 hours after the last administration of UFT. No significant undesirable interactions between UFT and OK-432 were exhibited during combination therapy of these agents in clinically administered doses. From our satisfactory results, clinical cures would be expected by the combined immuno-chemotherapeutic action of these agents.

[Immunohistological study of fibrinolytic factors of head and neck squamous cell carcinomas].

We investigated immunohistochemically the localization of urokinase-type plasminogen activator (u-PA), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), plasmin inhibitor (PI), and transforming growth factor-beta (TGA-beta) in tissue sections to examine the relationships between their localization and local invasiveness, tumor size and cervical lymph node metastasis of head and neck squamous cell carcinomas (SCCs). In invasive carcinomas, u-PA, PAI-1 and PI were stained stronger in carcinoma cells than in surrounding connective tissues or normal epithelial cells. However, no relationship was found between cell invasiveness and the localization of t-PA and TGF-beta in invasive SCCs. The expression of these factors was not related to cervical lymph node metastasis or the size of head and neck SCCs. These results suggest a disorder of the fibrinolytic systems of carcinoma cells, and that u-PA play a part in the invasion of head and neck SCCs by degenerating connective tissue.

Effect of lipid materials on the production of lipase by Torulopsis ernobii.

The yeast Torulopsis ernobii produced approximately 50 units of extracellular lipase (glycerol ester hydrolase, E.C. 3.1.1.3) per ml when grown in 30-liter fermentors at 33 C for 40 hr in a base medium at pH 5.0. The addition of fats, oils, triglycerides, or higher fatty acids to this medium at concentrations of 0.2 to 0.6% markedly increased production; twofold increases in yield were obtained when 0.2% olive oil or a mixture of 0.14% oleic acid and 0.04% palmitic acid was added. The production of lipase paralleled growth, and the role of lipid materials in augmenting lipase production appears to be related to cell growth.

Purification and properties of gamma-glutamyltranspeptidase from Bacillus subtilis (natto).

To understand the mechanism by which gamma-polyglutamic acid (gamma-PGA) in the sticky material of natto was synthesized, we purified the gamma-glutamyltranspeptidase (gamma-GTP) (EC 2.3.2.2) from the culture broth of Bacillus subtilis (natto) to homogeneity. gamma-GTP was composed of two subunits with molecular weight of 45,000 and 22,000. The N-terminal amino acid sequence of light subunit was homologous with that of gamma-GTP from Escherichia coli. The optimum pH and temperature of activity were 8.5 and 60 degrees C. The enzyme was inactivated by incubation for 15 min at pH 8.0 and 55 degrees C, but little loss of the activity was detected at 40 degrees C. gamma-GTP used glutamine as a gamma-glutamyl donor and acceptor for gamma-PGA synthesis. Dipeptides were better gamma-glutamyl acceptors than free amino acids.

A new immobilization technique of whole cells and enzymes with colloidal silica and alginate.

A mixed gel composed of colloidal silica and alginate (As gel) was prepared for the immobilization of enzymes or microorganisms. The physical strength of AS gel increased with the amount of colloidal silica. The ethanol production rate of Saccharomyces cerevisiae (IFO 0224) immobilized in AS gel was higher than in alginate gel (Al gel) in the early phase of growth. At a concentration of glucose of more than 10%, the ethanol production of immobilized yeast in AS gel was higher than in Al gel. Any difference was not recognized in the diffusion coefficient of glucose between AS and Al gels. The AS gel had an ability to retain proteins such as bovine serum albumin and gamma-globulin. The alkaline protease and beta-galactosidase in AS gel continued their function for a long time, but those immobilized in Al gel did not. Immobilized beta-galactosidase in AS gel had a higher thermal stability than in Al gel or free enzymes.

Detection of γ-Polyglutamic Acid (γ-PGA) by SDS-Page.

γ-Polyglutamic acid (γ-PGA) produced by Bacillus suhtilis (natto) was detected by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and basic dye staining. Using this method, the molecular weight of γ-PGA was estimated at 275,000. This value was almost the same in all bacterial strains tested. As other applications of this SDS-PAGE method, degradation of γ-PGA by acid and heat treatment and a cross-linking reaction with carbodiimide and ethylenediamine were made visible in acrylamide gel. In the growth curve of the bacteria, γ-PGA production was detected in early stationary phase by SDS-PAGE.

Relationship between head and neck squamous cell carcinomas and fibrinolytic factors. Immunohistological study.

Localization of t-PA, u-PA, PAI-1, PI and TGF-beta within tumors was examined immunohistologically in 31 patients with squamous cell carcinoma (SCC) of the head and neck, and correlations between the localization of these factors and local cancer infiltration, tumor size or cervical lymph node metastasis were investigated. The results revealed that u-PA, PAI-1 and PI tend to stain more intensely in infiltrating tumors than in peripheral connective tissue or normal epithelium, whereas neither t-PA nor TGF-beta showed any such tendency. Not all of these fibrinolytic factors participated in lymph node metastases or influenced tumor size in head and neck SCCs. These results suggest a disorder of fibrinolytic systems in carcinoma cells and that u-PA plays a part in the infiltration of head and neck SCCs by degenerating connective tissue.

Final report of a randomized controlled study with streptococcal preparation OK-432 as a supplementary immunopotentiator for laryngeal cancer.

We conducted a randomized controlled study of streptococcal preparation OK-432 on 120 newly identified cases of laryngeal squamous cell carcinoma who were registered at 10 participating institutions between November 1984 and October 1989. The patients were divided into two groups: those in early stages (stage I or II) and those in advanced stages (stage III or IV); these groups were further subdivided into an immunotherapy group (receiving OK-432) and a control group (who did not receive OK-432). The usefulness of OK-432 was studied using the sealed envelope method. The basic therapy for all cases was radiotherapy and, when required, surgery. As adjuvant therapy, 5Fu or derivatives were administered to all cases from the beginning of the treatment period to one year after the basic therapy, with the exception of cases in whom side effects were serious enough to contraindicate use of the drug. The target administration period was 5 years. Of the initial 120 cases, 11 cases were disqualified (3 cases of double cancer and 8 of incomplete primary therapy) and the remaining 109 were used for evaluation. The 5-year survival rate and the 5-year recurrence-free rate were 76% and 84%, respectively, in the immunized groups (both the early and advanced groups), whereas the same rates for the control groups were 78% and 75%. There was a tendency for the immunized groups to enjoy a slightly longer recurrence-free period. Over a 24-month observation period the immunized group always had higher levels of peripheral leukocytes and peripheral lymphocytes; this difference was significant for the first 21 months. Inhibition of bone marrow function is sometimes observed with radiotherapy. It is hoped that, if this inhibition can be mitigated, it will be possible to assist the compromised immune system and maintain a certain level of immune performance which will prevent recurrence and improve survival rate. In the present study we observed a tendency of the lower recurrence rate in the immunized group, and we hypothesize that OK-432 is effective in extending the recurrence-free period.

Therapeutic results in 40 patients with tongue cancer.

The therapeutic results in 40 newly diagnosed patients with tongue cancer treated in our department between January 1981 and December 1991 were evaluated. The 5-year survival rate of the 40 patients was 61.4%, and the cumulative 10-year survival rate was 53.7%. The 5-year survival rate in 15 patients who were in Stage I or Stage II was poor at 66.5%, and recurrence by metastasis to cervical lymph nodes was observed in 6 out of 8 patients who underwent surgery alone as the primary treatment.

DNA sequence of Bacillus subtilis (natto) NR-1 gamma-glutamyltranspeptidase gene, ggt.

The ggt encoding gamma-glutamyltranspeptidase (GGT) from Bacillus subtilis (natto) was cloned and sequenced. The DNA sequence contains a single open reading frame of 1761 bp that might be translated to a protein of 587 amino acid residues, and indicates that B. subtilis (natto) GGT is synthesized as prepro-GGT and processed later into large and small subunits. The putative catabolite responsive element (CRE) was located upstream of the ggt coding region.

Isolation and characterization of the alkaline protease gene of Aspergillus oryzae.

The genomic DNA for the alkaline protease (Alp) of the fungus Aspergillus oryzae was isolated using synthetic oligonucleotides as hydridization probes, and the complete nucleotide sequence was identified. The Alp gene is 1374 nucleotides long and contains three introns, one of which is in the pro region and two in the mature coding region. Sequences related to the TATA box (TATAAAT) and the CAAT box (CCAAAT) were found in the 5'-noncoding region. Primer extension analysis showed that three transcriptional start points are present.

A full length cDNA clone for the alkaline protease from Aspergillus oryzae: structural analysis and expression in Saccharomyces cerevisiae.

We have cloned and determined the nucleotide sequence of a cDNA fragment for the entire coding region of the alkaline protease (Alp) from a filamentous ascomycete Aspergillus oryzae. According to the deduced amino acid sequence, Alp has a putative prepro region of 121 amino acids preceding the mature region, which consists of 282 amino acids. A consensus sequence of a signal peptide consisting of 21 amino acids is found at the N-terminus of the prepro region. The primary structure of the mature region shares extensive homology (29%-44%) with those of subtilisin families, and the three residues (Asp 32, His 64 and Ser 221 in subtilisin BPN') composing the active site are preserved. The entire cDNA, coding for prepro Alp, when introduced into the yeast Saccharomyces cerevisiae, directed the secretion of enzymatically active Alp into the culture medium, with its N-terminus and specific activity identical to native Aspergillus Alp.

Secretion of Aspergillus oryzae alkaline protease in an osmophilic yeast, Zygosaccharomyces rouxii.

To produce Aspergillus oryzae alkaline protease (Alp) in an osmophilic yeast Zygosaccharomyces rouxii, we constructed an expression plasmid consisting of the Z. rouxii glyceraldehyde-3-phosphate dehydrogenase (GAPDH) promoter, the prepro-Alp cDNA of A. oryzae, the whole sequence of Z. rouxii plasmid pSR1, and the G418 resistant gene. The resulting plasmid, when introduced into Z. rouxii cells, directed the secretion of a large amount (about 300 mg/l) of Alp into the culture medium. The N-terminus and specific activity of the enzyme were identical to those of A. oryzae Alp.

Cloning and expression in yeast of a cDNA clone encoding Aspergillus oryzae neutral protease II, a unique metalloprotease.

The neutral protease II (NpII) from Aspergillus oryzae is a zinc-containing metalloprotease with some unique properties. To elucidate its structure, we isolated a full-length cDNA clone for NpII. Sequence analysis reveals that NpII has a prepro region consisting of 175 amino acids preceding the mature region, which consists of 177 amino acids. As compared with other microbial metalloproteases, NpII is found to be unique in that it shares only a limited homology with them around two zinc ligand His residues and that the positions of the other zinc ligand (Glu) and the active site (His) cannot be established by homology. When a plasmid designed to express the prepro NpII cDNA was introduced into Saccharomyces cerevisiae and the transformant was cultured in YPD medium (2% glucose, 2% polypeptone, 1% yeast extract), it secreted a proNpII. However, in a culture of the same medium containing 0.2 mM ZnCl2, it secreted a mature NpII with a specific activity and N-terminus identical to those of native NpII. This observation suggests that either an autoproteolytic activity or a yeast protease effected the processing.

Chemotherapy and granulocyte-colony stimulating factor for non-Hodgkin's lymphoma of the head and neck.

Granulocyte colony-stimulating factor (G-CSF) is believed to be useful for shortening the duration of granulocytopenia and for minimizing the decrease in the granulocyte count caused by chemotherapy for non-Hodgkin's lymphoma. In the present study we investigated the effect of G-CSF on bone marrow suppression caused by chemotherapy for non-Hodgkin's lymphoma of the head and neck. The leukocyte and neutrophil nadirs were significantly higher, while the duration of leukopenia, the time to recovery, and the time to the nadir were significantly shorter when G-CSF was administered prophylactically from 48 h after the completion of chemotherapy than when it was administered after the leukocyte and neutrophil counts had reached nadir. G-CSF had no influence on other blood cell components and caused no severe adverse events.

Tracking of hypopharyngeal carcinoma over 10 years.

Between September 1981 and July 1991 we treated 27 patients with squamous cell carcinoma of the hypopharynx. Almost all of the patients in the early stages received radiotherapy only, while patients in advanced stages received combination therapy involving chemotherapy, surgery and/or radiotherapy. Since 1987, chemotherapy has often been used to treat hypopharyngeal carcinoma in our department. Twelve patients received neo-adjuvant chemotherapy before surgery and/or radiotherapy. The 3-year survival rate for patients in the advanced stage treated with neo-adjuvant chemotherapy was 16.7% by the Kaplan-Meier method, and the 5-year survival rate of those treated without neo-adjuvant chemotherapy was 45.8%. The overall 5-year survival rate was 37.0%.