Transfection of BLV containing DNA into NIH 3T3 cells.

Cell DNA isolated from bovine leukosis virus (BLV) productive cell clones was transfected into the NIH3T3 cells. DNA from some cell clones was able to transform NIH3T3 cells. The transformed cells were cloned, and in 4 cell clones out of 33 bovine leukosis virus specific sequences were detected by hybridization with labeled BLV probe. According to the restriction analysis the BLV sequences were incomplete, they were rearranged, deleted, or both. The DNA from NIH3T3 transformants with BLV sequences was able to transform in the second round transfection experiments NIH3T3 cells again, but in these transformants BLV specific sequences were not detected. Cell DNA from sheep tumors induced by BLV was able to transform the NIH3T3 cells too, but BLV specific sequences were not present in the transformants. It appears that BLV specific sequences are not required for NIH3T3 cell transformation.

Medroxyprogesterone acetate versus tamoxifen in the therapy of advanced breast cancer.

A comparison of efficacies of medroxyprogesterone acetate (MPA) and the antiestrogen tamoxifen (TX) in the therapy for advanced breast cancer in patients who had already previously been intensely treated showed that, as to the objective remissions, the two drugs can be looked upon as equivalent. Nevertheless, with MPA a better analgetic and anabolic effect--a marked improvement in the performance status (Karnofsky index)--was achieved.

The investigation of the monocyte-mediated tumor-specific rosette formation and cytotoxic capacity of patients with thyroid cancer.

Fourteen patients suffering from highly differentiated thyroid cancer and 10 patients with autoimmune thyroid disease were tested in the present study. The tumor-specific autologous rosette formation of peripheral monocytes was determined and was found to be increased in cancer patients. Using the monocytes as effector and the covered, prelabelled autologous red blood cells as target, a cytotoxic assay was carried out. The rosette formation and cytotoxic ability correlated with the time passed since the operation, present clinical stage and the expansion of tumor found during the operation. In Hashimoto thyreoditis and Graves' disease elevated rosette formation and normal cytotoxic ability were detected.

Treatment of refractory leukemia with high-dose cytosine arabinoside.

Thirteen patients with refractory acute nonlymphocytic leukemia or with accelerated phase of chronic myeloid leukemia have been treated with high dose of cytosine arabinoside (Alcysten, Spofa). The drug was administered in doses of 3 g/m2/day. Six of 10 evaluable patients responded to the therapy. The mean duration of complete remission, achieved in 3 patients, was 18 weeks. The duration of partial remission ranged from 5 to 11 weeks. The treatment was well tolerated. Apart from expected hematological toxicity, transitory nausea and vomiting were the most frequently encountered side effects.

G-banding chromosome studies of acute lymphoblastic Lewis rat leukemia (KPH-Lw-I).

Changes of karyotype in spontaneous acute lymphoblastic Lewis rat leukemia have been studied by conventional Giemsa staining method and by G- and C-banding techniques. Comparing with previously published normal findings in first passages on rats, an increasing number of breaks, gaps and fragments in the 5th and 14th passages has been proved. Chromosomal investigation performed after two-year transplantation of leukemia on syngenic animals revealed pseudodiploid karyotype of leukemic lymphoblasts with the persistence of cell line 42, XX, del 2, -7, -18, +2 mar, that remained unchanged up to the latest examination in April 1984. Remarkable stability of chromosomal changes such as del 2 and 7/18 translocation might indicate possible insertion sites of transforming (viral) agent and/or localization of putative oncogenes.

Distribution of subpopulations of T lymphocytes in Hodgkin's disease.

In this paper, two aspects of T cell subsets are investigated. Splenic mononuclear cells (MNC) of untreated Hodgkin's disease (HD) patients have been investigated for proportion of immunoregulatory T gamma and T mu cells from 8 uninvolved spleens and 13 involved splenic tissues from HD patients with splenic involvement. As controls, two normal spleens from accident cases were used. It was found that irrespective of the involvement of splenic tissue in the disease process, the HD spleens showed lower percentage of T gamma cells (23.77 +/- 1.03) and higher sequestration of T mu cells (31.6 +/- 2.13) compared to normal spleens (42.5% and 13% resp.). However, there was no significant difference in the total T cell percentages of HD and normal spleens (49.1 +/- 1.13% and 52% resp.). The results therefore indicated the possibility of abnormal sequestration and traffic of T cell subsets in HD. We have also reported here a comparison between T cell subsets from the PBMNC of treated and untreated HD patients and normal healthy donors as assessed by the FcR markers and monoclonal antibodies of Leu series. It was found that the abnormality in T cell subsets could be demonstrated by FcR markers, while Leu 2a and Leu 3a reactivities did not differ in HD and normal PBMNC. The subset proportions identified by two tests did not tally with each other.

Spontaneous pulmonary metastasis of human cancer cells in X-irradiated and nonirradiated nude mice.

Effect of whole body X-irradiation on the spontaneous pulmonary metastasis of human cancer cells transplanted into adult nude mice was investigated. Human cancer cells were inoculated into footpads of adult nude mice following 3 Gy whole body X-irradiation. The incidence of pulmonary metastasis was increased in the irradiated mice. Cytotoxicity of the splenocytes, particularly adherent cells, was lower in the irradiated mice than in the nonirradiated mice. Histological examinations revealed decreased mononuclear cell infiltration around the primary tumor and pulmonary metastatic foci in the irradiated mice. The suppressive effect of cytotoxicity of the splenocytes by whole body X-irradiation may thus relate to ensuing metastasis both in the phase of release and intravasation from the primary tumor and in the phase of lodgement and proliferation in the target organ.

Monitoring of effects of cis-diamminedichloroplatinum II (Platidiam). Part II. Tests for mutagenic activity in the indicator system of Salmonella typhimurium his- strains (Ames test).

The mutagenic activity of the cytostatic drug Platidiam (cis-diamminedichloroplatinum II complex, cis-DDP) produced in Czechoslovakia was tested. In the used Ames test, as an indicator system, Salmonella typhimurium his- strains were employed. The tests for mutagenicity were performed in vitro using assays both without metabolic activation and therewith, as well as with metabolic activation under in vivo conditions. The analyses revealed a mutagenic effect of the cis-DDP complex in Platidiam in all of the followed tests. These effects were direct, no metabolic activation was observed. Furthermore, the mutagenic activity of the drug was influenced by the duration of interaction between Platidiam and the mammalian organism, which was apparently due to the pharmacokinetic properties of the active substance.

Stimulatory effect of potassium ions on MNU- and MNNG-induced mutagenesis in Salmonella typhimurium TA1535 and TA100.

The liquid suspension modification of the standard Salmonella mutagenicity assay employing Ames tester strains of Salmonella typhimurium TA1535 and T100 was used to study the influence of potassium, sodium and calcium on the mutagenic activity of MNU and MNNG. The toxic and mutagenic activities of MNU and MNNG were better expressed when potassium-containing solution was used as a solvent. Short-term pretreatment of bacteria cells with potassium-containing solutions increased the mutagenic efficiency of both chemicals. Potassium-induced increased sensibility of S. typhimurium TA1535 to MNU was completely reversible after 20 min incubation of bacteria in a nutrient broth at 37 degrees C. The mutagenic activity of MNU was reduced after a short-term pretreatment of S. typhimurium TA1535 with a 0.9% solution of CaCl2, while NaCl did not change the mutagenic response of bacteria to MNU.

New cytotoxic and antitumor agents. VII. Derivatives of 1-benzylidenisoindolin-3-one and 5,6-dihydro-8H-isoquinolo(2,3-a)phthalasin-5-one.

The in vitro cytotoxic effects on P388 leukemia cells of 19 derivatives and analogs of 1-benzylidenisoindolin-3-one, 5,6-dihydro-8H-isoquinolo(2,3-a)phthalasin-5-one and 4-benzyl-1,2-dihydrophthalasin-5-one were studied. The derivatives of the first group which preferentially inhibited uridine utilization were more effective. The cytotoxic effects of these substances depended on the quality of substituents, on the presence of a nitrogen atom in the 5-membered heterocycle of the molecule as well as on the spatial arrangement of the molecule. (Z)-narceine imide-N-oxide II and (Z)-3-(6-ethyl-2-methoxy-3,4-methylenedioxy) benzyliden-6,7-dimethoxy-isoindolin-3-one III were the most active agents, both of them causing a decrease in the proliferation rate of P388 cells. After its addition to the culture medium, compound III caused irreversible damages leading to death of the cells. The removal of the inhibitor did not lead to the repair of the damages either. Of the other two groups of substances, 5-hydroxy-3,4,12-trimethoxy-8-methyl-10,11-methylenedioxy-8H-isoquino lo (2,3-a)phthalasin (XVIII) had a marked inhibitory effect which, at concentrations of up to 25 micrograms ml-1, inhibited the proliferation rate of P388 cells.

Mouse testis weight loss and survival of differentiated spermatogonia following irradiation with 250 kV X-rays and 5.5 MeV fast neutrons.

Twenty eight after whole body irradiation of male BALB/c mice with 0.1-4.0 Gy of 250 kV X-rays or with 0.05-1.0 Gy of 5.5 MeV fast neutrons a decrease in testis weight and number of spermatozoa were observed. After plotting the testis weight loss against the radiation dose a mono-component curve characterized by D0 equal to 6.2 Gy and 1.31 Gy for X-rays and neutrons, respectively, was obtained. Relative biological effectiveness (RBE) was 4.25. Similar relation between the number of spermatozoa and the dose had a form of a two component curves. The sensitive components of the testis were characterized by the A-type curves with D0 equal to 0.49 Gy and 0.10 Gy for X-rays and neutrons, respectively. The resistant components were characterized by the B-type curves with D0 equal to 5.07 and 0.97 Gy for X-rays and neutrons, respectively. The RBE was 4.57. The obtained RBE values allowed to modify the total neutron dose and its fractionation in the therapy of malignant tumors at the Institute of Oncology, Krakow.

The role of blood platelet and fibrinogen in experimental metastasis in nude mice following whole body X-irradiation.

Human tumor cells were injected intravenously into nude mice following whole body X-irradiation and the number of platelets and the serum fibrinogen level in the blood were examined. Pulmonary metastasis was present in the irradiated mice but not in the non-irradiated mice. The number of platelets decreased rapidly after intravenous injection of the tumor cells and remained low in the irradiated mice, yet there was a recovery in the number in the non-irradiated mice. Serum fibrinogen level was increased in the irradiated mice and was decreased after intravenous injection in the irradiated mice, to a greater extent than seen in the non-irradiated mice. These findings may be related to trapping and lodgement of tumor cells in the target organ.

Humoral leukocyte adherence inhibition (H-LAI) before and after surgery in human breast cancer.

Eighty-four breast cancer patients were tested by the H-LAI method before and after surgery. In the cancer groups positive H-LAI responses could be stated in 90--100%. In benign breast diseases 94% positivity was also detected. The H-LAI values of the cancer patients did not change significantly at their discharge from hospital and only insignificant reduction in the H-LAI indices were detected even 3--12 months after mastectomy. The benign cases showed, however, a definite declining tendency in H-LAI after surgery.

Monoclonal antibodies against MHC class II antigens elicited with a human non-T, non-B acute lymphoblastic leukemia cell line.

A series of seven monoclonal antibodies recognizing cell surface antigens of similar distribution on a panel of leukemia/lymphoma and lymphoblastoid human cell lines was prepared by hybridoma technique after immunization with non-T, non-B acute lymphoblastic leukemia cell line REH. Immune reactivity of these monoclonal antibodies with B-lymphoblastoid and lymphoma cell lines, as well as with non-T, non-B leukemia cell lines but not with T-leukemic and myeloid leukemic cell lines (with the exception of myeloid leukemia cell line KG 1) was demonstrated by indirect immunofluorescence. No reactivity was observed with the examined human non-hemopoietic tumor cell lines, except melanoma cell lines HMB-2 and SK 1477. These antibodies immunoprecipitated a similar cell surface bimolecular glycoprotein complex consisting of two glycosylated chains (gp30, 35), as demonstrated by immunoprecipitation of cell surface 125I-lactoperoxidase radioiodinated, periodate/tritiated borohydride radiolabeled and 35S-methionine metabolically radiolabeled proteins of REH cells. These properties, typical of MHC class II antigens correspond also to immunoperoxidase staining of lymph nodes with some selected antibodies.

Hemopoietic cell line distribution and immunoprecipitation of cell surface proteins recognized by two newly prepared monoclonal antibodies elicited by a human non-T, non-B leukemia cell line.

Two newly prepared monoclonal antibodies elicited by a human non-T, non-B acute lymphoblastic leukemia cell line REH recognized distinct antigenic specificities characterized by the pattern of their immunofluorescence reactivities with a panel of hemopoietic cell lines and by immunoprecipitation of 125I-lactoperoxidase radioiodinated cell surface proteins, as well as periodate/tritiated borohydride radiolabeled cell surface sialoglycoproteins. Monoclonal antibody anti-p30 (BraFB6; IgG2b) recognized an antigen similar in its distribution to MHC class II antigens and immunoprecipitated a p30 cell surface protein, radiolabeled by lactoperoxidase catalyzed radioiodination. Monoclonal antibody anti-gp95 (BraEA10; IgG3) reacted in immunofluorescence intensively with non-T, non-B, T-leukemia and myeloid leukemia cell lines, less intensively with lymphoblastoid and lymphoma cell lines of B-phenotype and no reactivity was observed with examined non-hemopoietic human tumor cell lines. This antibody immunoprecipitated a lactoperoxidase radioiodinated and periodate/NaB3H4 tritium-radiolabeled cell surface sialoglycoprotein of approximately 95k (gp95) with variability in its apparent molecular weight, related to the origin of cells utilized for radiolabeling and immunoprecipitation.

A comparison of methods of monoclonal immunoglobulin quantitation.

Quantitation of monoclonal immunoglobulins was carried out using the following methods: densitometric scanning of electrophoretograms on cellulose acetate gel, single radial immunodiffusion, nephelometry and, in monoclonal IgM, also sedimentation analysis. To compare the methods, 20 sera with monoclonal IgG, 16 sera with monoclonal IgA and 19 sera with monoclonal IgM were used. The methods correlated well in monoclonal IgM and IgG while in IgA correlation was found only between densitometry and radial immunodiffusion. Closest correlation was observed between densitometry and sedimentation analysis in quantifying monoclonal IgM (r = 0.954). Despite good correlation, the individual values of monoclonal immunoglobulins established by different methods showed marked differences. In comparison with the immunochemical methods, the quantitation of monoclonal immunoglobulins using densitometric scanning of electrophoretograms is accessible, quick and relatively more precise method.

The Hp, Gc, Gm, Km and beta 2-glycoprotein I genetic variants in hairy cell leukemia: no apparent association.

No significant differences could be observed when Hp, Gc, Gm, Km and beta 2-glycoprotein I phenotypes of 50 patients with hairy cell leukemia were compared with healthy unrelated adults.

Technical evaluation of factors interfering in the carcinoembryonic antigen assay.

Storage of serum or plasma at room temperature (RT) or 4 degrees C for eight days did not alter the level of carcinoembryonic antigen (CEA). However, storage of whole blood at RT for 8 days resulted in false elevated CEA levels compared to controls. Heating of serum or plasma at 56 degrees C for 30 min or freezing and thawing for fifteen times did not change the CEA levels in these specimens. Comparison of CEA levels in the serum and plasma of the same specimens showed significantly higher levels of CEA in plasma than serum specimens. Collection of blood in tubes with different anticoagulants showed significantly false elevated levels of CEA only when blood was collected in heparinized tubes. These data indicate the importance of knowing the factors interfering in the CEA assay when interpreting its results.

Studies of metronidazole radiosensitizing effect in radiation treatment of patients with oral cavity cancer.

Clinical observations of 26 patients with tongue, oral cavity and oropharyngeal cancer receiving telegammatherapy by dynamic dose fractionation scheme in combination with metronidazole (MZ) and of 38 patients from control group treated by identical schedule without MZ suggest that MZ favors increasing of the radiation damage in tumors of those sites without changing the character or intensifying early radiation reactions. After oral administration of MZ in single doses of 5-6 g/m2 it reaches its maximum in the blood serum within 2-4 h. When the total dose of 30-60 g of MZ was used, a marked toxic effect manifested by gastrointestinal symptoms was observed in 33.3% of patients. MZ has a negative effect on liver functions, however, changes in biochemical tests illustrating it, are reversible and within the norm. Simultaneous studies of biopsy material from 22 patients (11 from each group) in terms of proliferation activity showed that oral cavity tumors contain a significant portion of proliferating cells which notably decrease in the course of radiation therapy. To a greater extent that decrease is marked after irradiation with MZ.

Epidemiological features of biliary tract cancer incidence in Slovakia.

This descriptive study is based on detailed data of biliary tract cancer incidence in Slovakia in the period 1968-1977. Age-adjusted incidence rates of biliary tract cancer in the given decade decreased in females while in males they showed a slight increase. The study of geographic distribution revealed diminishing incidence rates from west to the east in both sexes with extremely elevated rates in towns and suburban districts in males. Different shapes of age-specific incidence curves together with the identified histological types suggested different epidemiological characteristics of individual subsites within this site. Relatively high incidence rates of biliary tract cancer in Slovakia as well as in whole Czechoslovakia, in comparison with other countries or areas of Europe, could be related to the excessive prevalence of gallstones and high number of surgical interventions upon biliary tract in this country while the decreasing incidence rates in women coincided with elevated number of cholecystectomies. The significance of detailed descriptive data from cancer registries for further analytic and etiologic study of biliary tract cancer according to subsites for a better delimitation of high risk groups and primary prevention strategies is stressed.

Malignant tumors and embolizing paraneoplastic endocarditis.

A group of 4495 autopsied patients was evaluated. In 1011 (22.5%) of them various malignancies were found. In 20 of these cancer patients (2%) also a nonbacterial verrucous endocarditis was observed. The most serious complication of this paraneoplastic syndrome was central arterial embolization resulting in cerebral and myocardial infarctions. In our group this was observed in 12 patients (60%), in 9 cases of them infarction was the immediate cause of death. Fatal complications due to central embolization were seen also in 3 patients who had a malignant disease without symptoms of generalization. The most frequent tumors observed among the autopsied patients were adenocarcinomas of the digestive tract (40%). In the group of revealed tumors adenocarcinomas clearly prevailed (70%) in 10 cases (50%) also mucin production could be detected.

Alkaline phosphatase from human uterine myoma. II. Kinetic and immunological properties.

Thermostability of the purified alkaline phosphatase derived from human uterine muscle and myoma was established before and after desialization. Both enzymes were inhibited by sucrose, glucose and maltose in proportion to the carbohydrate concentration. L-Homoarginine inhibits the myoma enzyme in 90%, L-leucine, L-histidine and L-tryptophan in about 60%, and L-phenylalanine in less than 15%. The type of inhibition and Ki values were determined. Muscle and myoma enzymes cross-reacted with antisera against human liver and placental isoenzymes. Molecular and kinetic properties of the enzyme were compared with known human isoenzymes of alkaline phosphatase.

DNCB and PPD skin tests and prognosis in 152 patients with breast cancer. A prospective 2-year follow-up.

The relationship of pretreatment immunologic status in terms of skin tests to prognosis within stages was studied in 152 breast cancer patients. DNCB and PPD testing was used. As for DNCB, no relationship was found at early stages of the disease. In locoregionally advanced disease, patients with stronger test grades had longer disease-free intervals. In case of distant dissemination significant difference in reactivity with respect to survival was found: short survivors were more frequently nonresponders or mild responders. Anergy was, however, more frequent in patients with general ill health and therefore this test does not provide an important additional prognostic information as compared to that given by conventional clinical findings. As for PPD, no relationship between reactivity to this antigen and prognosis at any stage of the disease was found.

Changes in serum cathepsin B-like activity in patients with colorectal cancer.

Cathepsin B-like activity (CB-like) was estimated in sera of 30 male patients with colorectal cancer (n = 20), benign polyps of the rectum (n = 10) and in sera of control subjects (n = 50). Both total and residual activities of the enzyme in colorectal cancer patients showed a significant elevation in comparison with control subjects and patients with benign polyps. In the course of antitumor therapy a decline in catheptic activity was observed when a reduction in the volume of tumor tissue was present. On the other hand, an increment in CB-like activity was observed when antitumor therapy had no effects or tumor relapse was present.

Postnatal carcinogenic study of dimethylnitrosamine in rats.

Wist: Han/Pce SPF strain rats were administered dimethylnitrosamine (DMNA) in 0.04% concentration since the first day after birth. Total dose of 0.2 mg per infant rat was administered on 1st to 5th day of life, 0.4 mg/infant rat on 1st to 10th day and 0.5 mg on 1st to 20th day of life. Maximum survival time was one year. Both higher DMNA doses were already toxic the effect manifesting itself by increased mortality of the infant rats (liver hemorrhages, bleeding into the intestinal lumen) and reduced weight increment. Hepatic and renal tumors were detected in the rats beginning with their 19th week of life. In the liver they were hepatocellular carcinomas, to a lesser extent also cholangiomas and cavernomas. Further, increased incidence of preneoplastic nodular hyperplasia and benign hepatomas was demonstrated. In the kidney it was always the case of mixed mesenchymal tumor. Comparison of the results of postnatal study with a long-term carcinogenic DMNA study is discussed and possible reasons of different localization and characteristics of tumors dependent on DMNA administered were demonstrated.

bis-Mannich bases of styryl ketones as antileukemic agents.

A novel series of bis-Mannich bases have been synthesized and evaluated against P388 lymphocytic leukemia in mice. Two compounds showed a perceptible beneficial response in this screen and all the compounds displayed marked murine toxicity. A representative compound inhibited respiration in mitochondria isolated from rat and mouse liver cells by 90% approximately at a dose of 2.5 mumol and it caused a small elevation in mouse liver glutathione equivalent concentrations at 5 mg/kg.

Identification of a tumor-related protein antigen in immune complexes derived from pleural effusions of patients with bronchial carcinoma.

Pleural effusions from 15 patients with advanced primary bronchial carcinoma, from 2 patients with metastatic lung cancer and from 6 patients with nonmalignant disease were studied. Immune complexes were found in examined fluids in amounts corresponding to 2.5-210 mg/100 ml of aggregated IgG by means of ELISA solid phase anti C3 and 125ICIq binding radioimmunoassay. Following determination of protein content and salting out by ammonium sulfate of examined fluids, the sediments were subjected to subsequent chromatographic procedure including molecular sieving (Sephadex G-200, Sepharose 4B) and affinity chromatography on Protein A-Sepharose CL-4B. The yield--apparently pure immune complexes--was then split by means of chaotropic agent 2.5 M KSCN. It permitted to obtain 2 fractions: one contained IgG while the other was a non-Ig protein of m. w. = 150 000. The latter isolated from malignant effusions possessed antigenic activity in the leukocyte migration inhibition (LMI) assay. It resulted in inhibition of migration of allogenic peripheral blood leukocytes from lung cancer patients in 87% of cases. It had no activity against leukocytes from nonmalignant disease patients. LMI activity of the final second fraction derived from malignant effusion was significantly different from that of other fractions obtained both from malignant and nonmalignant fluids.

An experimental model for predicting the synergism of hyperthermia with cytostatics.

A simple prediction test for a combination of hyperthermia and chemotherapy checked on three experimental tumors and cells of the normal murine thymus is described. The testing procedure is based on checking the incorporation of labeled 125I 5-iodo-2-deoxyuridine into the DNA of tested cells affected solely by the enhanced temperature or by the cytostatic itself, or by a combination of both agents. The statistical analysis of repeated results demonstrated the reproducibility of the test. Testing of the potentiation effect of different non-cytostatic substances with enhanced temperatures also gave results corresponding to findings of other authors, performed in vivo or by the use of other techniques. Thus, this simple method is recommended for a screening, before considering the individual use of the combination of hyperthermia and chemotherapy in patients.

Immunological markers of peripheral blood and lymph node lymphocytes in Hodgkin's disease.

The lymphoid subpopulations of peripheral blood and cell suspensions of lymph nodes were investigated in a series of 20 patients with Hodgkin's disease (HD) by conventional surface markers and a panel of 11 monoclonal antibodies (McAb). In peripheral blood of HD, the number of T lymphocytes and the distribution of helper and suppressor/cytotoxic subpopulations was normal, suggesting that the alteration in cell immunity in this condition is either due to a functional defect in T cells or to an alteration in the immunoregulatory mechanisms which are not directly dependent on T lymphocytes. The lymph nodes involved by HD showed an increase in the number of T helper lymphocytes (OKT4+) as compared with the reactive lymph nodes from 14 subjects used as a control group. In involved lymph nodes there was a good correlation between the number of lymphocytes reacting with the McAb OKT3 and EEAT rosette--forming cells, whereas in most hyperplastic nodes the number of T3 lymphocytes was greater than that of E+ rosettes. Hodgkin and Reed-Sternberg cells did not react either with T, B lineage specific McAb or with myelomonocytic (OKM1) or monocytic (Mo2, FMC-17, FMC-33) McAb. These results would make a monocyte-macrophage lineage origin unlikely also for these cells.

Carcinoembryonic antigen fraction in digestive cancer.

A clinical study in a group of patients with digestive cancers was done with a radioimmunoassay technique employing a carcinoembryonic antigen (CEA) fraction. Among 45 patients with colorectal carcinomas, 51% showed CEA levels in the pathologic range before therapy, those with metastatic disease from well differentiated adenocarcinomas showed the higher values. Measurement of the circulating levels of this CEA fraction proved to be more useful in the monitoring of the course of disease during and after antineoplastic treatment. Sensitivity of the radioimmunoassay technique for the remaining digestive cancers was over 50%, but pathologic CEA values are not exclusive for malignant digestive disease, since 22% of patients with benign diseases also showed raised serum levels of CEA.