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PubMed1976

Studies on specific humoral immunity in leukemia.

The paper concerns some results in studies on humoral immunity in human and animal leukemia obtained in author's laboratory (1970-1974). The data presented here disclose immunological mechanisms of mice viral leukemogenesis (cytotoxic and blocking antibodies interrelations). The existence of specific humoral immune response in acute leukemia patients was established (immunoglobulins with the properties of antibodies were revealed in 42.6% of patients). Different forms of specific humoral immunity manifestations in different types of leukemia were distinguished (areactive, nonspecific, cytotoxic, blocking and mixed forms.

Animals↗
PubMed1994

Kinetics of tissue disposition of cis-ammine/cyclohexylamine-dichloroplatinum(II) and cisplatin in mice bearing FSaIIC tumors.

The clinical potential of mixed amine platinum(IV) complexes has been identified, and interest in this new class of antitumor agents has been heightened by demonstration of their activity in cisplatin-resistant neoplasms. These tetravalent platinum agents are expected to undergo a reductive reaction to form the corresponding platinum(II) drug prior to eliciting biological activity. cis-Ammine/cyclohexylamine-dichloroplatinum(II) is one such product that we evaluated with cisplatin in vivo, and we found the two complexes given i.v. or i.p. to have comparable activities against a solid murine fibrosarcoma. Following i.v. administration of the two compounds at equitoxic dose levels (20 mg/kg) to tumor-bearing mice, platinum levels in the plasma were consistently higher for cisplatin. Tissue platinum levels, in contrast, were comparable between the agents or higher for the mixed amine analog at the earliest (3-h) time point. The temporal profiles determined for the concentrations over 48 h were tissue- and/or drug-specific and could be described by terminal-phase constants or half-lives of platinum in most tissues. In the plasma, kidney, lung, and jejunum, platinum levels arising from both compounds decayed with half-lives of 24-92 h. The terminal-phase constants of platinum determined in the heart for the two complexes were not significantly different from zero, indicative of levels remaining steady, whereas the constants were negative in the spleen, indicative of an increase in tissue drug concentration. In the tumor, liver, and testes, positive values for the decay-phase constants corresponding to half-lives of 47, 256, and 79 h, respectively, were seen with the mixed amine complex; this pattern contrasted with that found for cisplatin, for which the terminal-phase constant was either zero or negative. In vitro binding studies demonstrated the mixed amine complex to be more reactive. Thus, the presence of one ammine and one cyclohexylamine carrier ligand in the mixed amine complex, as opposed to the diammine ligands in cisplatin, leads to an increase in drug distribution and an alteration in the kinetics of tissue binding and removal of platinum.

Animals↗
PubMed2001

Key peptide processing enzymes are expressed by breast cancer cells.

The expression of the three key peptide processing enzyme families, represented by CPE, PAM, and PC1/3 plus PC2, were examined in MCF-7 and ZR-75-1 breast cancer cell lines. Both of these cell lines express vasopressin receptors as well as the vasopressin gene, but the processing of vasopressin gene-related proteins appears to be limited. Products of the expected size for, CPE, PAM and PC1/PC3 could be amplified by reverse transcription-polymerase chain reaction (RT-PCR) from both cell lines. Cloning and sequencing of these RT-PCR products revealed that each enzyme mRNA had a structure identical to that published for the human form of the respective enzyme. Western analysis provided evidence that mRNAs for these enzymes are translated into proteins. Alternatively, PC2 mRNA was identified to be present in MCF-7 cells both by RT-PCR and Western blot analysis, but could not be demonstrated for ZR-75-1 cells. Our findings suggest that the key processing enzymes needed to generate active vasopressin and other neuropeptide growth factors are present in breast cancer cells.

Blotting, Western↗
PubMed1988

Detection of new MHC mutations in mice by skin grafting, tumor transplantation and monoclonal antibodies: a comparison.

Two mechanisms of major histocompatibility complex (MHC) mutations have been described in mice; gene conversion and homologous but unequal recombination. However, our knowledge of mutations in MHC is incomplete because studies have been limited almost exclusively to two haplotypes, H-2b and H-2d, while hundreds of haplotypes exist in nature; it has been biased by the use of only one procedure of screening for mutation, skin grafting. We used three procedures to screen for MHC mutations: (1) conventional techniques of skin grafting, (2) syngeneic tumor transplantation and (3) typing with monoclonal anti-MHC antibodies (mAbs) and complement. The faster technique of tumor transplantation detected mutants similar to those discovered by skin grafting technique. Screening with mAbs allowed us to detect both mutants that are capable of rejecting standard skin grafts and those that are silent in skin grafting tests, and which therefore resulted in a higher apparent mutation frequency. Two mutants of the H-2a haplotype were found that carry concomitant class I and class II antigenic alterations. Both MHC mutants silent in skin grafting tests and mutants carrying concomitant class I and class II alterations have never been studied before and are expected to reveal new mechanisms of generating MHC mutations. 1-Ethyl-1-nitrosourea (ENU) failed to induce de novo MHC mutations in male mice in our skin grafting series.

Animals↗
PubMed1994

Epidermoid cyst of the testis: a review of clinical and histogenetic considerations.

OBJECTIVE: To review the records of patients with epidermoid cysts and those with germ cell tumours to determine the most appropriate method of treatment. PATIENTS AND METHODS: The records of the patients treated for epidermoid cysts and testicular germ-cell tumours in a period covering 22 years were analysed retrospectively. Nine specimens with an epidermoid cyst were examined by immunohistology for the presence of testicular intraepithelial neoplasia (TIN) (or carcinoma in situ of the testis). RESULTS: Ten patients with a simple epidermoid cyst and 481 patients with testicular germ-cell tumour were treated during the observation period. The relative incidence of epidermoid cysts in relation to the number of patients with testicular germ-cell tumours was 2.1% (95% confidence interval 0.8-3.35%). The mean age of the 10 patients with an epidermoid cyst was 24.1 years. The right testis was affected in seven patients and the left in three. Six of these patients received conservative surgery with excellent cosmetic results. No relapse had occurred after a median observation period of 30 months. Immunohistological staining for placental alkaline phosphatase disclosed the absence of TIN in the parenchyma surrounding the cysts. CONCLUSION: The absence of TIN calls into question the common assumption that an epidermoid cyst constitutes a monodermal teratoma. Two distinct entities of epidermoid cyst are proposed--one occurring in conjunction with a teratoma or a germ cell tumour (a 'complex' or 'mixed' epidermoid cyst) and the other a 'simple' epidermoid cyst without TIN in the adjacent tissue and thus representing a benign neoplasm that is not a teratoma. The absence of TIN near a simple epidermoid cyst justifies testis-sparing surgery.

Adolescent↗
PubMed2000

Endoscopic ultrasound characteristics of mucinous cystic neoplasms of the pancreas.

OBJECTIVE: Mucinous cystic neoplasms of the pancreas have a more favorable prognosis than ductal adenocarcinoma. Management of a subgroup, intraductal papillary-mucinous neoplasms, is controversial. Endoscopic ultrasound (EUS) with fine-needle aspiration biopsy may emerge as the imaging modality of choice. There are few studies describing the EUS features of these tumors. METHODS: A total of 35 consecutive cases of cystic tumors of the pancreas with an established pathological diagnosis were analyzed for characteristic EUS features. RESULTS: Mucinous cystadenocarcinomas (n = 14) were more likely to be characterized by hypoechoic cystic/solid mass or complex cyst and were frequently associated with a dilated main pancreatic duct. Benign mucinous duct ectasia (n = 6) were characterized by a dilated main pancreatic duct in conjunction with hyperechoic thickening of the duct wall. The two cases of intraductal mucinous hyperplasia additionally showed a hypoechoic mass. Intraductal papillary carcinoma (n = 11) had features in common with mucinous cystadenocarcinoma but also had echogenic foci in the mass and intraductal hyperechoic lesions. The two cases of microcystic cystadenoma showed either a mixed hypoechoic solid/cystic mass or a complex cyst without the additional features seen in mucinous cystadenocarcinoma. CONCLUSIONS: EUS features seem to exist that may help to differentiate cystic neoplasms from adenocarcinoma of the pancreas and, thus, to establish the preoperative diagnosis of cystic tumors of the pancreas.

Adult↗
PubMed1990

[Cytotoxicity of lymphocytes sensitized by autologous tumor cells in vitro, against autologous lung cancer cell lines].

In order to obtain killer lymphocytes that would have a strong cytotoxicity against autologous tumor cells, we conducted a cytotoxic assay of effector cells cultured from human peripheral blood lymphocytes (PBL) using 10 cultured lung cancer cell lines as target cells. We present this result. (1) Lymphocytes obtained by 17 days mixed lymphocyte tumor cell culture (MLTC: Fresh PBL from lung cancer patients was mixed with irradiated autologous tumor cells in a medium, and cultured for 3 days. Irradiated allogeneic lymphocytes were then added, and cultured for 14 days) were cytotoxic against 4 of the 10 autologous lung cancer cell lines. (2) Lymphocytes obtained by 14 days MLTC and 3 more days culture in a medium containing interleukin 2 were cytotoxic against all 10 of the autologous lung cancer cell lines. These lymphocytes proliferated to 4.13 times of the original cell number, and their surface marker was OKT3+. These killer lymphocytes are expected to be effective in adoptive immunotherapy as effector cells.

Adult↗
PubMed1984

Carcinogenic and toxicologic effects of inhaled ethylene oxide and propylene oxide in F344 rats.

The chronic inhalation toxicity and carcinogenicity of ethylene oxide (EO) and propylene oxide (PO) were evaluated in a 2-year inhalation bioassay. Five groups of male weanling Fischer 344 rats, 80 per group, were exposed at 0 ppm (shared control; filtered air), 50 ppm EO, 100 ppm EO, 100 ppm PO, or 300 ppm PO (7 hr/day, 5 days/week) for 104 weeks. Body weights from rats exposed to EO and PO at all exposure concentrations were significantly reduced compared to controls. A statistically significant increase in mortality was observed in all groups of exposed rats compared to controls. Skeletal muscle atrophy in the absence of any sciatic nerve neuropathology was found in rats exposed at 100 ppm EO and 300 ppm PO. Statistically significant associations between EO exposure and an increased incidence of the following rat neoplasms were observed: mononuclear cell leukemia, peritoneal mesothelioma, and mixed cell brain glioma. Among rats exposed to PO there was a dose-dependent increase in the incidence of complex epithelial hyperplasia in the nasal passages, and two adenomas were detected in the nasal passages of rats exposed at 300 ppm PO. The incidence of adrenal pheochromocytomas was elevated in both PO exposure groups, but not in a dose-related manner. All rat groups were affected by an outbreak of Mycoplasma pulmonis infection which occurred about 16 months into the study. This infection alone and in combination with the epoxide exposures affected the survival of rats in this study, and influenced the development of the proliferative lesions in the nasal mucosa of the PO-exposed rats. No treatment-related changes in any clinical chemistry or urinalysis indices were detected. PO exposure did not increase the incidence of the three neoplasms associated with EO exposure; however, adrenal pheochromocytomas and proliferative lesions of the nasal cavity were increased in rats exposed to PO.

Animals↗
PubMed1990

Carcinosarcoma of the spermatic cord.

The first case of carcinosarcoma in the spermatic cord is reported in a 40-year-old man. The tumor was a 2.5 X 2 cm pseudoencapsulated formation located in the connective tissue of the spermatic cord among the blood vessels. Light microscopy examination of the neoplasm revealed two different histological patterns: epithelial and sarcomatous. Mitoses and atypias were infrequent in both types of areas. The epithelial cells formed papillary and gland-like structures stained with PAS, Hale and mucicarmine stains, and showed positive reaction for immunohistochemical demonstration of both keratin and epithelial membrane antigen. The lumen content of the gland-like structures reacted positively for the carcinoembryonic antigen. Electron microscopy revealed that the epithelial cells were joined by junctional complexes and displayed numerous short microvilli. The sarcomatous areas consisted of spindle cells embedded in a ground substance that occasionally presented myxoid changes. Mast cells and focal calcifications were seen. Sarcomatous cells showed positive reaction for vimentin but not for the other histochemical and immunohistochemical techniques mentioned above. The ultrastructure of sarcomatous cells was similar to that of epithelial cells except for the occurrence of small desmosomes instead of junctional complexes. The differential diagnosis with adenomatoid tumor and malignant mixed mesothelioma is discussed.

Adult↗
PubMed1994

Bifunctional peptidylglcine alpha-amidating enzyme requires two copper atoms for maximum activity.

The conversion of C-terminal glycine-extended peptides to C-terminal alpha-amidated peptides occurs in two distinct reactions, both of which are catalyzed by bifunctional peptidylglycine alpha-amidating enzyme. The first step is the alpha-hydroxylation of the C-terminal glycine residue and the second step is the dealkylation of the alpha-hydroxyglycine-extended peptide to the alpha-amidated peptide and glyoxylate. We show that the bifunctional enzyme requires 1.9 +/- 0.2 mol of copper/mol of enzyme for maximal dansyl-Tyr-Lys-Gly amidation activity under the conditions of high enzyme concentration (approximately 80 microM) required to measure initial rates for this poor substrate. The enzyme, as purified, contains a substoichiometric amount of copper and has only trace levels of amidation activity. Addition of exogenous Cu(II) ions stimulates amidation activity approximately 3000-fold at the optimum copper stoichiometry and the enzyme is then inhibited by excess Cu(II). No stimulation of amidation activity is observed upon the addition of the following divalent metal ions: Mn(II), Fe(II), Ni(II), Cd(II), and the oxovanadium cation, VO(II). The enzyme-catalyzed dealkylation of alpha-hydroxyhippuric acid to benzamide shows no dependence on copper, indicating that the copper dependence of the amidation reaction must be attributed to a copper dependence in peptide alpha-hydroxylation.

Amino Acid Sequence↗
PubMed2000

Induction of peptidylglycine alpha-amidating monooxygenase in N(18)TG(2) cells: a model for studying oleamide biosynthesis.

The fatty-acid primary amide, oleamide, is a novel signaling molecule whose mechanism of biosynthesis is unknown. Recently, the N(18)TG(2) cell line was shown to synthesize oleamide from oleic acid, thereby demonstrating that these cells contain the necessary catalytic activities for generating the fatty-acid primary amide. The ability of peptide alpha-amidating enzyme, peptidylglycine-alpha-amidating monooxygenase (PAM; EC 1.14.17.3), to catalyze the formation of oleamide from oleoylglycine in vitro suggests this as a function for the enzyme in vivo. This investigation shows that N(18)TG(2) cells, in fact, express PAM and that cellular differentiation dramatically increases this expression. PAM expression was confirmed by the detection of PAM mRNA, PAM protein, and enzymatic activity that exhibits the functional characteristics of PAM isolated from mammalian neuroendocrine tissues. The regulated expression of PAM in N(18)TG(2) cells is consistent with the proposed role of PAM in the biosynthesis of fatty-acid primary amides and further establishes this cell line as a model for studying the pathway.

Animals↗
PubMed1992

Selective inactivation of the hydroxylase activity of bifunctional rat peptidylglycine alpha-amidating enzyme.

Conversion of dansyl-Tyr-Val-Gly to dansyl-Tyr-Val-NH2 by recombinant type A rat 75-kDa peptidylglycine alpha-amidating enzyme (alpha-AE) is inactivated by ascorbate, dehydroascorbate, and hydrogen peroxide in a time- and concentration-dependent manner. Both ascorbate- and dehydroascorbate-mediated inactivation are saturable with apparent kinact/Kinact values of 1.7 and 0.23 s-1 M-1, respectively. Hydrogen peroxide-mediated inactivation is not saturable with a second-order rate constant of 50 s-1 M-1. Peptidyl-Gly substrates, EDTA, and H2O2 scavengers protect against ascorbate-mediated inactivation while EDTA and semidehydroascorbate scavengers protect against dehydroascorbate-mediated inactivation. Under similar conditions, ascorbate, dehydroascorbate, and H2O2 have no effect on the alpha-AE-catalyzed conversion of dansyl-Tyr-Val-alpha-hydroxyglycine to dansyl-Tyr-Val-NH2 which is consistent with the hypothesis that the 75-kDa enzyme consists of distinct peptidyl-Gly hydroxylase and peptidyl-alpha-hydroxyglycine lyase active sites.

Amino Acid Sequence↗
PubMed1994

Incomplete processing of progastrin expressed by human colon cancer cells: role of noncarboxyamidated gastrins.

Gastrin is mitogenic for several colon cancers. To assess a possible autocrine role of gastrin in colon cancers, we examined human colon cancer cell lines for expression of gastrin mRNA and various forms of gastrin. Gastrin mRNA was not detected in the majority of colon cancer cell lines by Northern hybridization but was detected in all human colon cancer lines by the sensitive method of reverse transcriptase-polymerase chain reaction (PCR). Gastrin mRNA was quantitated by the competitive PCR method. The majority of cell lines expressed very low levels of gastrin mRNA (< 1-5 copies/cell); only one cell line expressed > 20 copies/cell. The mature carboxyamidated form of gastrin was not detected in any of the cell lines by radioimmunoassay or immunocytochemistry. Results suggested that either gastrin mRNA expressed by colon cancer cells was altered (mutated) or posttranslational processing of progastrin was incomplete. Gastrin cDNA from all the colon cancer cell lines had an identical sequence to the published sequence of human gastrin cDNA. Specific antibodies against precursor forms of gastrin were used, and significant concentrations of nonamidated (glycine-extended) and prepro forms of gastrin were measured in tumor extracts of representative colon cancer cell lines. The presence of precursor forms of gastrin suggested a lack of one or more of the processing enzymes and/or cofactors. Significant concentrations of the processing enzyme (peptidylglycine alpha-amidating monooxygenase) were detected in colon cancer cells by immunocytochemistry. Therefore, lack of other cofactors or enzymes may be contributing to incomplete processing of precursor forms of gastrin, which merits further investigation. Since low levels of gastrin mRNA were expressed by the majority of human colon cancer cell lines and progastrin was incompletely processed, it seems unlikely that gastrin can function as a viable autocrine growth factor for colon cancer cells. High concentrations of glycine-extended gastrin-17 (GG) (> 10(-6) M) were mitogenic for a gastrin-responsive human colon cancer (DLD-1) cell line in vitro. It remains to be seen if GG or other precursor forms of gastrin are similarly mitogenic in vivo, which may then lend credibility to a possible autocrine role of gastrinlike peptides in colon cancers.

Base Sequence↗
PubMed1997

Artificial-capillary-system development of human alloreactive cytotoxic T-lymphocytes that lyse brain tumours.

The production of alloreactive cytotoxic T-lymphocytes (CTL) for therapy of recurrent brain tumours was performed in the CELLMAX artificial capillary system composed of cell-culture modules containing cellulose acetate or cuprammonium rayon hollow fibres. Lymphocytes, obtained from the brain-tumour patient to be used for sensitization, were stimulated with OKT3 (anti-CD3) and interleukin-2 (IL-2) and inoculated into the extracapillary space of artificial capillary modules. For allogeneic CTL production, the expanded patient lymphocytes were harvested, irradiated and placed into a second artificial capillary system with allogeneic lymphocytes from a healthy donor. In a one-way mixed lymphocyte reaction, CTL developed in the presence of low-concentration IL-2 (60 i.u. of IL-2/ml). In 18-21 days the cell preparation usually displayed a predominantly CD3+, CD8+ phenotype, which consorted with the dual-labelled CD8/CD11a markers used to identify CTL. Chromium (Cr)-release assays demonstrated lysis of patient tumour in relation to allogeneic glioma; the response observed in cold-target-inhibition assays confirmed lysis of the relevant tumour by the CTL.

Antibodies, Monoclonal↗
PubMed1990

Effect of secretagogues on components of the secretory system in AtT-20 cells.

The mouse corticotrope tumor cell line AtT-20/D16v was used to investigate the effects of chronic treatment with various secretagogues on individual components of the secretory pathway. Secretagogues acting in part through receptors linked to guanine nucleotide-binding regulatory proteins [CRF and somatostatin (SS)] and agents by-passing membrane receptors (phorbol myristate acetate and dexamethasone) were examined. Effects on the secretory product were evaluated by measuring levels of pro-ACTH/endorphin mRNA and hormone secretion. Effects on posttranslational processing enzymes were evaluated by measuring levels of the mRNAs encoding carboxypeptidase-E and peptidyl-glycine-alpha-amidating monooxygenase (PAM); cellular levels of PAM activity were also measured. The mRNAs encoding the G-proteins in AtT-20 cells were identified, and secretagogue effects on the G-protein signal transduction system were evaluated by measuring levels of the mRNAs encoding (alpha s, alpha)i2, and beta 2. No single parameter adequately characterizes the regulatory state of the complex secretory apparatus. Although levels of pro-ACTH/endorphin (PAE) mRNA accurately reflected hormone secretion after chronic CRF or dexamethasone treatment, chronic SS treatment elevated PAE mRNA levels in the face of reduced hormone secretion. Levels of PAM mRNA generally changed in parallel with levels of PAE mRNA; in contrast, levels of carboxypeptidase-E mRNA were unaffected by any of the secretagogues tested. Secretagogues acting through distinct G-proteins (CRF and SS) as well as dexamethasone brought about a coordinate increase in the level of the mRNAs encoding the three G-protein subunits examined. Treatment with phorbol myristate acetate caused a slight decrease in the levels of the G-protein subunit mRNAs.

Animals↗