bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum lipoproteins of rats bearing transplanted morris hepatoma 7777
Authors: Narayan K. Ananth , Morris Harold P.
Published: February 2007

The serum lipoprotein patterns of Buffalo‐strain rats bearing hepatoma 7777 were determined in the 2nd, 4th and 5th weeks after transplantation of the tumor. The result indicated the presence of a slow‐moving HDL component which was similar to that observed previously in Holtzman rats given 0.03% N‐2‐fluorenylacetamide. Five weeks after transplantation of the tumor, the serum lipoproteins were isolated ultracentrifugally and quantified by chemical analyses and by disc electrophoresis using a protein stain. These results have confirmed the increase in serum lipoproteins, especially the high density lipoprotein, HDL2, in these tumor‐bearing rats. The serum total lipid, cholesterol and phospholipid were considerably increased while the total serum proteins were only slightly elevated in rats with tumors as compared to control rats. A new α1‐globulin component was observed in the serum protein patterns in the tumor‐bearing rats.
Clinical features and treatment of childhood malignant lymphoma in Uganda
Authors: Ziegler J. L. , Morrow R. H. , Templeton A. C. , Templeton C. , Bluming A. Z. , Fass L. , Kyalwazi S. K.
Published: February 2007

A series of 66 patients with Burkitt's lymphoma or childhood lymphoma of the histiocytic or lymphoblastic type has been analysed. The six patients with histiocytic lymphomas had clinical features, response to therapy and survival rates which clearly distinguished this group from Burkitt's lymphoma. Of the six patients with lymphoblastic lymphomas, however, three presented with clinical features indistinguishable from Burkitt's lymphoma while two had facial tumors which showed atypical features. The response to chemotherapy with CTX was more favorable in the lymphoblastic than in the histiocytic group, and the survival rate in this small number of patients falls midway between those of histiocytic lymphoma and Burkitt's lymphoma. Thus, the clinical evaluation of Ugandan children with lymphoblastic lymphoma did not clearly distinguish this group from patients with Burkitt's lymphoma, and casts some doubt on the use of clinical features or response to therapy as diagnostic criteria.
Cancer in the parsi community of bombay
Authors: Paymaster J. C. , Gangadharan P.
Published: February 2007

A study of the distribution of cancer in the Parsi community has brought to light certain important differences existing between this community and other communities of Western India. Such variations may be due to the habits and customs of the Parsis and perhaps in a small measure to ethnic characteristics. There is a striking preponderance of cancer at certain sites such as the anterior two‐thirds of the tongue, the female breast and the uterus. In contrast, the disease is far less frequent in the buccal mucosa, base of the tongue, cervix and lung than in other communities.
Burkitt's lymphoma and malaria
Authors: Kafuko G. W. , Burkitt D. P.
Published: February 2007

The distribution of Burkitt's lymphoma is related to endemicity of malaria, not only on a world‐wide basis, but also in more detailed studies in East Africa, particularly in Uganda. This geographical association, together with the diminished incidence of AS haemoglobulin in patients with this tumour and the increased susceptibility to lymphoma formation in mice infected with chronic malaria, suggest a causal relationship.
EB viral antigens in burkitt tumor biopsies and early cultures
Authors: Nadkarni J. S. , Nadkarni J. J. , Klein G. , Henle W. , Henle G. , Clifford P.
Published: February 2007

The emergence of cells producing EB viral antigens in cultures of Burkitt tumor biopsies was studied by means of immunofluorescence techniques. Definitely or questionably positive cells were seen in acetone‐fixed smears of 6% and 29% of the biopsies, respectively, which amounted to no more than a few cells among several hundred thousands. Yet in culture, specifically stainable cells often appeared within 3 to 10 days, occasionally in substantial numbers (up to 5%). Repeated biopsies from the same donors gave remarkably similar results. In time all cultures which developed into lines showed the presence of EBV. Arginine‐free medium failed to facilitate emergence of EBV antigen‐producing cells in young cultures or to increase their number, unless about 0.5% or more of the cells in the control cultures were productively infected. The implications of these findings are discussed.
Inheritance of susceptibility to friend mouse leukemia virus. VII. Establishment of a resistant strain
Authors: Odaka Takeshi
Published: February 2007

Based on the previous observation that a single major autosomal locus controls susceptibility to Friend leukemia virus in mice, an attempt was made to place the gene for resistance, Fvr, from resistant C57Bl/6 mice into the genetic background of susceptible D D D mice. The cross‐intercross system was adopted for this purpose, the mice with Fvr/Fvr genotype being selected by progeny test at each even‐numbered generation. During successive matings, the effect of gene Fvr was not diluted out, and progeny were almost always obtained as expected from the single gene hypothesis. After five to six cycles of cross‐intercross, brother‐sister mating was done between the mice with Fvr/Fvr genotype. The progeny are homozygous for gene Fvr and could be assumed to be congenic with D D D mice except for susceptibility to Friend leukemia virus. In the mice of this strain, the virus does not induce typical splenomegaly, but multiplies to a considerable level. It could therefore be concluded that the locus Fv is involved rather in cell proliferation than in virus multiplication.
Loss of T antigen by cells derived from a hamster tumour induced by adenovirus type 12
Authors: Vasconcelos‐Costa J.
Published: February 2007

Cells from a second transplantation of an adenovirus type 12‐induced hamster tumour were cultured and, at the seventh subculture, frozen in liquid nitrogen with 10% DMSO. Later, these cells were cultured in the same conditions as the parent cells. They kept the morphological and growth characteristics and the tumorigenicity of the cells from the former culture. The synthesis of surface antigen was maintained but T antigen and tumour‐specific transplantation antigen were not detectable. The possibility of a relation between the antigen loss and the freezing treatment is discussed.
Inactivation DU virus leucémogène de gross par les radiations UV, X et γ
Authors: Latarjet Raymond
Published: February 2007

A passage cell‐free extract from AKR leukemia was irradiated: a) with UV light (2,537 Å); b) with X‐ and γ‐radiation acting under direct effect conditions. After irradiation, the residual activity of the extract was compared to those of serial dilutions of the non‐irradiated extract. The criterion for activity was the “acceleration test” in new‐born AKR mice. Four experiments were carried out with UV light, 3 with X‐, and 2 with γ‐rays. In each experiment, the effects of 4 doses of radiation were compared to those of 4 10‐fold dilutions of the non‐irradiated control. In all, 1,835 new‐born mice were utilized. The Gross virus is inactivated according to an exponential function of the dose of radiation. The doses D10, which reduce the viral activity of the extract to one tenth of its original value were found to be:

The viral function, which is involved in these tests, seems to be the leukemogenic activity (transformation), rather than the infectivity (viral multiplication).
Tumor induction with single urethan injection in newborn and adult syrian golden hamsters. A study on age influence. I.
Authors: Toth B.
Published: February 2007

Single subcutaneous injections of 1 mg urethan per g body weight were administered to newborn and 8‐week‐old randomly bred Syrian golden hamsters. The treatment ersulted in the induction of higher numbers of forestomach papillomas in animals receiving urethan at adult age than or birth. It gave rise to similar incidences of dermal melamocytomas inthe ovo age groups. Other tumors were also observed in the animals. Since only a few were seen of each type, it is difficult to relate their appearnace to the treatments. It is concluded that ageplays a role inh the oncogenic response of golden hamsters challenged by a single chemical stimulus. The ersults aer discussed in the light of previous studies performed in this field.
Studies on the mechanisms of invasion in cancer. I. Isolation and purification of a factor chemotactic for cancer cells
Authors: Yoshida Kenshi , Ozaki Teruhisa , Ushijima Kenichiro , Hayashi Hideo
Published: February 2007

A substance chemotactic for cancer cells was extracted from the pseudoglobulin fraction of some tumor tissues of animal and human origin. It was highly purified by column chromatography using Sephadex G‐50 and CM‐Sephadex and then by disc electrophoresis; it behaved as a homogenous substance on disc electrophoresis. The substance was a protein with a molecular weight of approximately 70,000. It was thermolabile and had no proteolytic activity. The material was similarly active for rat ascites hepatoma AH109A cells, mouse ascites hepatoma MH134 cells and mouse myeloid leukemia C‐1498 cells, suggesting a common chemotactic action. It was ineffective for polymorphonuclear leukocytes of rats. No such chemotactic activity was demonstrated by the protein fraction from normal skin and muscle.
Inhibition by germ‐free status of development of liver and lung tumours in mice exposed neonatally to 7,12‐dimethylbenz(A)anthracene: Implications in relation to tests for carcinogenicity
Authors: Roe F. J. C. , Grant G. A.
Published: February 2007

Germ‐free (GF) status significantly “protected” male C3H mice from the early (before 40 weeks) development of liver‐cell tumours in response to 7,12‐dimethylbenz(a)anthracene (DMBA) given shortly after birth. GF status significantly protected C3H mice of both sexes from the early development of adenomas of the lung in response to the same treatment, and may have protected DMBA‐treated C3H female mice from the development of malignant lymphoma, mammary, ovarian and uterine tumours. Age in excess of 80 weeks counteracted the protective effect of GF status. GF status had no consistent effect on the incidence of sarcomas at the site of neonatal injection of DMBA. The fact that a factor as non‐specific as the difference between normal micro‐biological status and GF status may have such a profound effect on the age‐standardized risk of development of lung and liver tumours in mice, suggests that the term “carcinogen” should not be applied to an agent if the only evidence of relevant activity is that it increases the risk of development of either or both these types of tumour in mice. Possible mechanisms, including immunological mechanisms, by which GF status influences the response to DMBA are discussed and the need for further studies is stressed.
Group‐specific antigen of murine leukemia viruses in mice of low‐leukemic strains
Authors: Abelev G. I. , Elgort D. A.
Published: February 2007

The distribution of group‐specific antigen of murine leukemia viruses (MuL V‐gs) was studied in mice of low‐leukemic strains: C57BL/6, C57BL/10Sn, BALB/c and others. A rabbit monospecific anti‐MuLV‐gs serum was used for the antigen detection. The analyses were carried out by an indirect immunoradioautography technique which permitted the detection of trace amounts of the antigen. MuLV‐gs was found in the spleen of mice of all strains studied. It was present in mouse embryos as well as in adult animals.
Immunofluorescent study of the group‐specific antigen of murine leukemia viruses
Authors: Lejneva O. M. , Abelev G. I.
Published: February 2007

In the present work a method is described for obtaining monospecific antibodies to the group‐specific antigen of the murine leukemia viruses (MuLV‐gs). This antigen is demonstrated in normal and malignant tissues by the indirect immunofluorescence technique. The MuLV‐gs was demonstrated in Rauscher leukemic spleen cells of BALB/c mice and in normal spleen cells of high‐leukemic AKR and some low‐leukemic mice. The MuLV‐gs was shown in cells of methylcholanthrene‐induced sarcomas and in cells of tumors induced with polyoma virus. The MuLV‐gs was not revealed in III Af mouse sarcoma induced by Rous virus.

The specificity of the reaction was confirmed by the specific inhibition of the fluorescence after neutralization of the antibodies by the partly‐purified MuLV‐gs. The results obtained with the immunofluorescence technique coincided with those of agar precipitation analysis.
Studies on cellular immunity to human neuroblastoma cells
Authors: Hellström Ingegerd , Hellström Karl Erik , Bill Alexander H. , Pierce George E. , Yang James P. S.
Published: February 2007

A colony inhibition technique was used to demonstrate immune reactions mediated by peripheral blood lymphocytes against tumor‐associated (specific?) antigens of human neuroblastomas. Lymphocytes from all of 11 patients carrying actively growing neuroblastomas, as well as lymphocytes from all of 11 patients who were clinically symptomfree after therapy for neuroblastomas, inhibited colony formation of plated neuroblastoma cells. They did not inhibit normal skin fibroblasts derived from the same patients as the tumor cells. A specific colony inhibition of neuroblastoma cells was also seen with lymphocytes from 12 of 16 mothers of children with neuroblastomas and with lymphocytes from some fathers and siblings of such patients. No specific inhibition of neuroblastoma cell colony formation was seen with lymphocytes from patients not having neuroblastomas or from healthy subjects.

Serum from six of six patients with progressively growing neuroblastomas, but from none of four patients who were clinically symptom‐free after treatment for such tumors, could block lymphocyte‐mediated colony inhibition of plated neuroblastoma cells. It is suggested that the former sera contained antibodies which could mediate an efferent form of immunological enhancement.
Genetic deletions at specific loci by polycyclic hydrocarbons in relation to carcinogenesis
Authors: Fahmy O. G. , Fahmy Myrtle J.
Published: February 2007

The genetic properties of four benz[a]anthracene derivatives with varying carcinogenic potential were investigated on the stages of spermatogenesis in Drosophila melanogaster: two carcinogens, the 7,12‐dimethyl compound and its 7‐bromomethyl‐12‐methyl analogue; and two non‐carcinogens, methylated in the 1,7 or 3,9 positions. All proved virtually inactive with respect to the induction of point‐mutations: sex‐linked and autosomal recessive visibles and lethals. They were also ineffective in the production of chromosome breaks leading to major rearrangements, such as viable X‐fragments.

Specific mutability tests confirmed the inactivity of all compounds on representative loci within the euchromatin of the X‐chromosome. In contrast, they were active to various degrees in the deletion of those loci involved in the transcription of r‐RNA, as measured by the effect on the heterochromatic X‐nucleolar organizer region, yielding bobbed mutations. The carcinogenic derivatives induced a high frequency of these mutations, whereas the non‐carcinogens were virtually inactive. The compounds which were active on the nucleolar organizer were also effective on the Minute loci.

The mutagenic efficiency of the carcinogenic derivatives on the responsive loci proved to be differential, dependent on the chemical structure of the carcinogen and the metabolic activity of the target cells. The bearing of this phenomenon on specificity in carcinogenesis was discussed.
Development of resistance of novikoff hepatoma TO 5‐fluoro‐2'‐deoxyuridine
Authors: Wolberg William H.
Published: February 2007

Three strains of Novikoff hepatoma were studied in tissue culture; the N1‐S1 or FUDR‐sensitive strain, N1‐S1/FUDR which is grown in and is resistant to 1 × 10−5M FUDR, and the cells which emerged as FUDR‐resistant after 10 generations when N1‐S1 was exposed to 1 × 10−7M FUDR. Inhibition of growth of N1‐S1 cells by FUDR was related to the concentration of the drug in the medium. The uptake of formate and serine into DNA‐thymine of these cells was inhibited by FUDR and the degree of inhibition was likewise proportional to the concentration of drug in the medium. The cells derived from N1‐S1 which were resistant to FUDR resembled the stable resistant strain, N1‐S1/FUDR, in that they lacked the ability to incorporate thymidine into DNA at 4.0 × 10−8M. Such cells apparently had less thymidine kinase activity and consequently also had a decreased ability to convert FUDR to the active monophosphate. Because of the decrease in thymidine kinase activity, the resistant strain, N1‐S1/FUDR, utilized thymidine as a source for DNA‐thymidine to a lesser extent than did the sensitive strain N1‐S1. However, both strains used serine and formate as the source of the 5‐methyl carbon of DNA‐thymidine to a similar extent.

Growth studies in shaker flasks with a mixture consisting of 75% N1‐S1 and 25% N1‐S1/FUDR cells treated with FUDR demonstrated that rapid overgrowth by the 25% resistant cells obscured the significant killing of sensitive cells by the drug. Clonal studies revealed that a small portion of cells resistant to FUDR were present in the sensitive N1‐S1 strain of cells. The number of colonies which survived depended upon the concentration of the drug, but approximately 0.6% of the N1‐S1 cells grew in the presence of 1 × 10−5M FUDR. These studies led to the conclusion that the development of drug resistance in this system was actually a process of selection by which FUDR killed a certain percentage of cells determined by its concentration. Biochemically resistant cells which were present as a small proportion of the original “sensitive” tumor continued to proliferate and ultimately emerged as the dominant population.
Induction of lymphoma in BALB/c mice by Rowson‐Parr virus (RPV)
Authors: Carter R. L. , Chesterman F. C. , Rowson K. E. K. , Salaman M. H. , Wedderburn N.
Published: February 2007

The long‐term pathological effects of Rowson‐Parr virus (RPV), injected intravenously into 84 young adult BALB/c mice, are described. In the main experiment, 70 test mice and 30 uninjected control mice were examined serially between 4 and 48 weeks. A second group of 14 injected animals were allowed to live out their life‐span. Four stages in the host response have been defined. Splenic hyperplasia predominates in Stages I and II: there is initially a short‐lived phase of moderate splenic enlargement and reactive hyperplasia (Stage I) which partly resolves, to be followed by a persistent period of slight splenomegaly and low‐grade (non‐specific) reactive hyperplasia (Stage II). Neoplastic changes (Stages III and IV) developed in almost 45% of test mice in the serial study. In most instances, the neoplastic process appears to arise in reticulum cells in the Malpighian follicles of the spleen and is initially confined to these structures (Stage III). Later (Stage IV) there is progressive replacement of the splenic pulp and increasing involvement of lymph nodes, liver and thymus; some animals develop a terminal leukaemia. A similar reticulum‐cell neoplasm was found in many of the RPV‐infected mice which were allowed to live out their life‐span; none of these animals survived for more than a year after infection. Four RPV‐infected mice developed lymphomas and leukaemias of other histological types. No reticulum‐cell neoplasms were found in the uninjected control animals.

Certain features of the reticulum‐cell lymphoma associated with RPV are discussed. Emphasis is directed to two features; (1) the biphasic nature of the host response with respect to time, the lymphoma being preceded by long‐sustained reactive changes; and (2) the finding that reactive and neoplastic changes arise sequentially in the same organ, and perhaps involve the same cell‐type—splenic reticulum cells. In contrast to findings in several other murine lymphomas, the thymus is not apparently involved until late in the disease.

It is clear that RPV can no longer be regarded as “a virus of minimal pathogenicity”.
Possible carcinogenic hazards of several tars and of locacorten‐tar ointment (spectro‐fluorescent investigations and experiments in animals)
Authors: Shabad L. M. , Khesina A. Ja. , Linnik A. B. , Serkovskaya G. S.
Published: February 2007

The content of benz (a)pyrene (BP) in some tars and the carcinogenic effect of the ointment, Locacorten‐Tar, has been investigated in our laboratory. The determination of BP was performed by the spectrofluorescence technique based on Shpolsky's effect in frozen crystalline solution of normal paraffins. The concentration of BP in wood tars varied from 0 to 338.2 μg/g, whereas that of BP in coal tars is about 15 times higher (5,000μg/g). In Locacorten‐Tar it was 225 μg/g. Locacorten‐Tar ointment was tested in C57 X CBA mice by skin application. By the end of the treatment (after one year) all surviving animals had malignant skin tumours (carcinomas and sarcomas), which metastasized and were transplantable. BP estimation can apparently serve as an indicator of the carcinogenicity of tars and ointments. The determination of its content may serve as one of the criteria for selecting constituent compounds for ointments.
Tumor‐associated immunogolobulins. The elution of IgG2 from mouse tumors
Authors: Ran Maya , Witz Isaac P.
Published: February 2007

In an attempt to detect and characterize immunoglobulins fixed in vivo onto tumor cells, a low pH buffer was used to dissociate the tumor cells from the bound immunoglobulins. IgG2 could be eluted from intact cells and from a membrane‐rich‐sub‐cellular fraction originating from primary muose banzo (a)pyrene‐indueced tumors and from spontaneous mammary tumors, indicating the association of this immunoglobulin with the surfac of the tumor cells. Significantly lower amounts of IgG2 were present in eluates of membrane‐rich fractioins originating from transplantable benzo(a) pyrene induced sarcomas. IgG1 was not detecetd in most of the tumor eluates. Membrane‐rich sub‐celluar fraction originating from normal mouse muscle did not contain any detectable immunoglobulin.

On the basis of a semi‐quantitative estimation of IgG2 and IgGi in the serum of normal and tumor‐bearing mice, it was concluded that IgG2 is preferentially bound to tumor cells and is not a random contaminant of the cells or of the membrane‐rcih sub‐cellular fractions.
Detectioni and isolatinio of tumour‐specific antigen associated with a spontaneously arising rat mammary carcinoma
Authors: Baldwin R. W. , Embleton M. J.
Published: February 2007

Cell surface expressed tumour‐specific antigen was detected in one (Sp4) of eight spontaneously arising rat mammary carcinomas by membrane immnofluorescence tests with viable tumour cells in suspensioni and sera from syngeneic rats immunized against each tumour. These findings are consistent with the frequency of expression of significant tumour antigenicity as defined by transplantation methods. Also the tumour antigen detected by membrane immunofluorescence tests in mammary carcinoma Sp4 showed the individual characteristics as the tumour‐specific transplantation antigens, and no evidence was obtained of weak common antigens in these tumours.

Tumour‐specific antigen in subcellular fractions of mammary carcinomas Sp4 was assayed by its capacity to absorb antibody from tumour‐immune sera. By this criterion, it was established that plasma membrane fractionis retained tumour‐specific antigen although recoveries were low, amounting to less than 5% of cell‐surface experssed antigen. In comparison, almost total recovery was obtained of alloontigen experessed on mammary carcinoma Sp4 cells. Plasma membrane fractioins from mommary carcinoma Sp4 lacked the capacity to induce tumour rejectino reactions in syngeneic rats although a weak humoral antibody response was obtained. These findings contrast with the more consistent immune response elicted by heavily irradiated mammary carcinoa Sp4 cells.
Transplantation immunity following immunization with extracts of adenovirus 12 tumour cells
Authors: Potter C. W. , Oxford J. S.
Published: February 2007

Extracts were prepared from transplanted adenovirus‐12 tumours of both hamsters and CBA mice by freezing and thawing and centrifugation at 100,000 x g/1 h. Extracts from CBA mice were also filtered through Millipore filters. These extracts were found to induce immunity to tumour cell challenge. Immunization with similar extracts of hamster tumours induced by SV40 of CELO virus did not induce immunity in CBA mice to tumour development. The results indicate that a possibly soluble extracts of adenovirus 12 tumour transplantation antigen can be obtained, and this antigen can be assayed in the adenovirus‐12‐induced CBA mouse tumour system.
Humoral responses to tumour xenografts in ALS‐treated mice
Authors: Beverley P. C. L. , Simpson Elizabeth
Published: February 2007

An isotopic antiglobulin technique was used to study the humoral response to a hamster tumour grafted into ALS‐treated or normal mice. Approximately 50% of ALS‐treated animals fail to reject the tumour after cessation of ALS treatment. All ALS‐treated animals show a delayed humoral response compared to controls but in those animals which fail to reject tumours, a high level of serum antibody is maintained even in the presence of a large tumour mass.
Lethal reticuloproliferative disease induced in Cebus albifrons monkeys by Herpesvirus saimiri
Authors: Meléndez L. V. , Hunt R. D. , Daniel M. D. , Fraser C. E. O. , García F. G. , Williamson M. E.
Published: February 2007

Four cinnamon ringtail monkeys (Cebus albifrons) inoculated intramuscularly with Herpesvirus saimiri died between 18 and 20 days after inoculation. Each of the four monkeys presented an extensive infiltration of reticulum cells in various organs (liver, lungs, kidney, pancreas, spleen, thymus, lymph node). The character of the infiltrate closely resembled reticulum cell sarcoma thus providing further evidence of the high oncogenic capacity of Herpesvirus saimiri.
Epstein‐Barr virus (EBV)‐associated antibody patterns in malignant lymphoma and leukemia. I. Hodgkin's disease
Authors: Johansson Bo , Klein George , Henle Werner , Henle Gertrude
Published: February 2007

Sera from Swedish patients with Hodgkin's disease as well as control sera from donors without known disease were titrated for antibodies to the Epstein‐Barr virus (EBV) by the indirect immunofluorescence technique. In the same sera antibodies capable of blocking the direct membrane immunofluorescence reaction obtained between Epstein‐Barr virus carrying lymphoblastoid cell lines and a fluorescein‐conjugated reference serum from a patient with Burkitt's lymphoma (F‐Mutua conjugate) were tested. The serological reactivity of the control sera was very similar to that described in previous reports. In contrast, sera from Hodgkin's disease patients showed an increased reactivity in both tests. When the donors were grouped in relation to clinical and histological data of prognostic importance, an inverse relationship was found between the frequency of lymphoid cells and EBV‐associated serological reactivity. Whereas paragranuloma cases did not exceed the reactivity level of the controls, patients with Hodgkin's sarcoma were highly reactive in both tests, reaching levels comparable to those seen in Burkitt's lymphoma and nasopharyngeal carcinoma. The granuloma group was intermediate with regard to serological reactivity.
Effects of prolactin or growth hormone on growth of carcinogen‐induced mammary tumors of adreno‐ovariectomized rats
Authors: Nagasawa Hiroshi , Yanai Reiko
Published: February 2007

The effects of exogenous administration of bovine prolactin and bovine growth hormone (GH) on 7,12‐dimethylbenz(a)anthracene (DMBA)‐induced mammary tumor were investigated in female Sprague‐Dawley rats. Rats were bilaterally adrenoovariectomized 15 days after the appearance of the first palpable mammary tumors and were treated with either prolactin or GH beginning the next morning. Marked stimulation of incidence and growth of mammary tumor and of normal mammary gland growth followed subcutaneous injections of 1.25 or 2.5 mg prolactin twice daily for 20 days. GH had no effects on mammary tumor, whereas it accelerated the growth of normal mammary gland and increased the body weight. The administration of 2.5 mg prolactin twice daily for 10 days, beginning 20 days after adreno‐ovariectomy, raised the number and size of regressed mammary tumors to the pre‐operative levels, while the half dose of prolactin had no effects.

These results indicate that prolactin is the principal hormone responsible for the growth of DMBA‐induced mammary tumor of the rat, whereas GH has only a minimal role in the growth of the tumor.
The relation of metabolism to macromolecular binding of the carcinogen benzo[a]pyrene, by mouse embryo cells in culture
Authors: Duncan Margaret E. , Brookes P.
Published: February 2007

The metabolism of tritiated benzo[a]pyrene (B[a]P) by primary mouse embryo cells in culture was studied. At concentrations of B[a]P in the medium below about 2–3 mμ moles/ml, metabolism was exponential with time, but at higher concentrations a period of rapid metabolism was followed by a progressive decline. The extent of binding of the hydrocarbon to DNA, RNA and protein was studied under the above conditions. It was found that at low doses of hydrocarbon the binding to macromolecules was proportional to the overall metabolism, with the result that the binding index, i.e. the amount of hydrocarbon bound divided by the amount metabolized, was constant. At higher dose levels, overall metabolism did increase with dose whereas macromolecular binding reached a plateau value. This resulted in a fall in the “binding index” below the constant value found at low doses of B[a]P.

As a consequence of these results and those of other workers, a model scheme is proposed for the enzymic metabolism of B[a]P which accords with the known facts of metabolism and macromolecular binding.
Effect of neuraminidase on electrophoretic mobility and immune cytolysis of human uterine cervix carcinoma cells
Authors: Vasudevan D. M. , Balakrishnan K. , Talwar G. P.
Published: February 2007

The electrophoretic mobility of human uterine cervix carcinoma cells at pH 7.2 was found to be 0.89 μ/sec/v/cm at 25®C, while normal human cervix cells had a mobility of 0.58 μ/sec/v/cm. Treatment of the carcinoma cells with neuraminidase for 30 min reduced the electrophoretic mobility to 0.46 μ/sec/v/cm. Neuraminidase liberated more N‐acetyl‐neuraminic acid from carcinoma cells than from normal cells. Immune cytolysis of carcinoma cells by lymphocytes was studied by means of.

51.

Cr‐release technique. Autologous and homologous lymphocytes from carcinoma cervix patients had a lytic effect on carcinoma cervix cells; and the cytolysis was increased about two‐fold when the malignant cells were treated with neuraminidase. Homologous lymphocytes from healthy donors had comparatively little cytolytic action on malignant cells. Autologous lymphocytes had virtually no effect on normal cervical cells and neuraminidase treatment did not affect their susceptibility to lymphocytes. Autologous and homologous serum from cancer patients had a cytolytic influence on malignant cells; but normal serum was without effect. Although calcium chloride reduced the negative surface charge on the malignant cells, as gauged by their electrophoretic mobilities, no increase in the cytolysis of carcinoma cells by autologous lymphocytes was observed in the presence of charge‐reducing concentrations of calcium chloride.

These results suggest the possibility that in the case of cervical carcinoma, sialic‐acid‐containing moieties partially mask tumor‐specific antigens on cell surface and prevent their recognition by immunologically competent cells of the host.
Modifications ultrastructurales de la surface des cellules BHK 21/13 transforméES, DÉPENDANT DE NUCLÉOTIDES DE L'ADÉNINE
Authors: Torpier G. , Montagnier L.
Published: February 2007

ULTRASTRUCTURAL CHANGES OF THE SURFACE OF BHK 21/13 TRANSFORMED CELLS, DEPENDING ON ADENINE NUCLEOTIDES

BHK 21/13 cells transformed by either RNA or DNA oncogenic viruses have a modified surface, as shown, at the ultrastructural level, by an increase in the affinity of this surface for the dye ruthenium red. This increase takes place only when the cells have been grown in the presence of adenine nucleotides. Since the same nucleotides are required for the growth of these cells in agarose medium containing sulfated polysaccharides, it is suggested that this transformation character is related to the observed surface changes.
Demonstration of cell‐mediated immunity to human neoplasms of various histological types
Authors: Hellström Ingegerd , Hellström Kark Erik , Sjögren Hans Olov , Warner Glenn A.
Published: February 2007

Peripheral blood lymphocytes from a total of 373 tumor patients were tested by either a colony inhibition or a cytotoxicity test for cell‐mediated immunity against human neoplasms of various histological types. Lymphocytes from 51 of 59 patients studied (88%) either reduced colony numbers formed by plated autochthonous tumor cells or were cytotoxic to them, and lymphocytes from 78 of 87 patients tested (89%) had a similar effect on allogeneic tumor cells of the same histological type as those of the lymphocyte donors. Evidence indicating antigenic cross‐reactivity between tumors of the same histological type was obtained for the following seven groups of neoplasms: malignant melanomas, carcinomas of the colon, breast, testis, endometrium and ovary, and various sarcomas. Lymphocytes affecting tumor cells had no effect on normal cells from the same patient, or on cells from other types of neoplasms than the target cells under study.

The degree of cell‐mediated immunity, as detectable with the techniques employed, was approximately the same in patients having active neoplastic disease as in patients who were clinically symptom‐free. Eleven of 12 patients who were tested after having been symptom‐free for more than 2 years had a lymphocyte‐mediated anti‐tumor immunity.
Lysosomal changes and enhanced metastatic growth: An experimental study of the effects of some non‐ionic surfactants
Authors: Carter R. L. , Birbeck M. S. C. , Stock J. A.
Published: February 2007

The effects on metastatic growth of Triton WR‐1339 and three chemically related non‐ionic detergents have been investigated in 40 hamsters bearing subcutaneous transplants of a metastasizing lymphoma (ML). Ten further untreated animals with tumour grafts and 20 normal animals without tumour grafts acted as controls. In hamsters without tumours, the four detergents commonly produced three hepatic changes: an increase in the liver/body weight ratio, an increase in stainable acid phosphatase, and an increase in the number and size of the lysosomes, together with ultrastructural changes. In tumour‐bearing animals, the detergents all produced a paradoxical effect, partially inhibiting growth of the tumour graft but markedly facilitating metastatic spread. More organs contained secondary tumours in the test groups, and the pattern of involvement in certain organs (liver, kidneys) was strikingly altered, with diffuse rather than focal metastatic growth. Detailed investigations of the liver established that treated animals all showed the same (but more profound) changes as those seen in detergent‐treated hamsters without tumours‐i.e., high liver/body weight ratios, high acid phosphatase scores, and lysosomal damage. No lysosomal lesions were found in untreated tumour‐bearing hamsters.

In the discussion, it is stressed that the detergents tested acted principally on host (cf. tumour) tissues, and it is suggested that local lysosomal damage in lysosome‐rich organs such as the liver may be one factor whereby these detergents facilitate local tumour spread. Ways in which lysosomal lesions may affect local tumour growth are discussed, and analogies are drawn from previous work relating to lysosomal changes and the (associated) enhanced growth of mycobacteria. The implication of the present findings in relation to the old “soil” hypothesis of metastatic growth are indicated but the fallacies of premature generalizations about lysosomal changes and metastasis are stressed.
Malignant transformation induced by 7,12‐dimethylbenz(a)anthracene in rat embryo cells infected with rauscher leukemia virus
Authors: Rhim Johng S. , Vass William , Cho Han Y. , Huebner Robert J.
Published: February 2007

This report describes morphological transformations observed approximately 6 weeks after treatment of Rauscher leukemia virus (RLV) infected rat embryo (RE) cells with various levels of 7,12‐Dimethylbenz(a)‐anthracene (DMBA) for 7 days. Uninfected cells treated with DMBA and RLV‐infected RE cells untreated with DMBA failed to show any evidence of transformation. When stained with Giemsa, the foci of transformed cells consisted of randomly oriented criss‐crossing spindle‐shaped cells, having much more rapid replication rates than the untreated and untransformed RE cells. The transformed cells were more resistant to the toxicity of DMBA than were the untransformed RE cells. Local subcutaneous sarcomas were produced when the transformed cells were transplanted into newborn rats, whereas the infected or DMBA‐treated untransformed cells produced no tumors. Cells derived from the tumors, when re‐established in tissue culture, like the tumor tissue itself contained group‐specific (GS) complement‐fixing antigens characteristic of the murine leukemia‐sarcoma virus complex and the C‐type RNA particles. These results, which showed that both chemical and virus were required for transformation, suggest that the C‐type RNA viral genome of RLV provided specific oncogene information for the malignant transformation.
Studies on the mechanism of action of 5‐aziridinyl‐2,4‐dinitrobenzamide (CB 1954), a selective inhibitor of the walker tumour
Authors: Connors T. A. , Melzack D. H.
Published: February 2007

CB 1954, a monofunctional alkylating agent, has exceptional activity against the Walker carcinoma yet is inactive against a large number of other animal tumours. A line of the Walker tumour with acquired resistance to CB 1954 was cross‐resistant to Melphalan, implying a common mechanism of action, although other tumours highly sensitive to Melphalan were not affected by CB 1954. CB 1954 was also similar to Melphalan in its effects on DNA and RNA synthesis. No correlation was observed between binding of CB 1954 to the DNA of tumour cells and their sensitivity to it. Differences in response of the Walker tumour when incubated with Melphalan and CB 1954 suggest that the latter agent may have some features of an anti‐metabolite. In preliminary experiments, its selective anti‐tumour effect against the Walker carcinoma has been completely reversed by an intermediate in purine biosynthesis.
Studies on murine sarcoma virus: II. Detection of group‐specific antigens by immunofluorescence
Authors: Chuat Jean‐Claude , Lasquellec Françoise , L'hirondel Anne‐Marie , Boiron Michel
Published: February 2007

The group‐specific (GS) antigen of murine tumor viruses was demonstrated by immunofluorescence in mouse cells recently infected by mouse sarcoma virus, strain Moloney (MSV‐M), with the serum of rats carrying long‐transplanted MSV‐M tumors. GS antigen was detected 15 h post‐infection and was also present in various mouse and rat cell lines chronically infected with murine tumor viruses. The antigen was strictly localized in the cytoplasm of infected cells and was also found in mouse and rat cells chronically infected by members of the two major subgroups of murine tumor viruses. Further, the sera employed were shown to contain exclusively GS antibodies and the tumors used for immunization were found by several techniques to be free of virus envelope (V) antigens after a given number of passages in vivo. V antigens were visible only at the cell membrane and the time course of appearance of both GS and V antigens in recently infected cells was parallel. In contrast, GS antigen was not observed in two hamster tumor lines transformed by MSV‐M.
Recherche de particules virales dans des lignées cellulaires de hamster transformées par le virus de rous investigations on the presence of viral particles in rous transformed hamster cell lines
Authors: Gazzolo L.
Published: February 2007

In the framework of a study on the recovery of the Rous Sarcoma Virus (RSV) from transformed mammalian cells, nine Syrian hamster cell‐lines transformed by RSV were examined by electron microscopy. Six of these lines were obtained from BHK 21/Clone 13 cells transformed in vitro by RSV, either Schmidt‐Ruppin strain (SR‐RSV) or Bryan strain (B‐RSV), one of them being supertransformed by polyoma virus. Another line (RSH) was obtained from embryonic hamster cells transformed in vitro by SR‐RSV. Two lines resulted from in vivo experiments: SR/Cl2 was obtained from a SR‐RSV‐induced tumour in a Syrian hamster; and RS2‐TH2 represented an in vitro cultured tumour obtained in a Syrian hamster by the inoculation of RS2 cells transformed in vitro by SR‐RSV. All these lines had the group‐specific antigen (GS) and it was possible to rescue RSV from all lines except SR/Cl2 when they were cultivated in association with permissive chick cells.

No C‐type virus particles could be observed either in the six lines transformed in vitro or in two lines (RSH and SR/Cl2) transformed in vitro. On the contrary, the line RS2‐TH2 contained C‐type particles, morphologically similar to murine leukemia virus, and probably representing a latent hamster virus. In line SR/Cl2, A‐type particles were found associated with mitochondria. The significance of the presence of these particles in this only non‐virogenic line is discussed. Finally, in all the hamster lines examined, R‐type particles were observed. They were more numerous in the in vivo transformed lines than in the in vitro transformed lines.
Some biophysical aspects of e‐b virus adsorption to the surfaces of three types of mammalian cells
Authors: Weiss L. , Horoszewicz J. S.
Published: February 2007

The electrokinetic properties of the surfaces of three types of cultured mammalian cells, in established lines, were studied to determine whether these properties could be correlated with adsorption of EB virus, as observed by electron microscopy and immunofluorescent techniques.

As both viruses and cells carry a net negative surface charge, computations were made of the interactions between them using colloid theory. The results show that knowledge of various macroscopic surface parameters does not enable predictions to be made on whether viruses will adsorb or not. Modification of net surface charge by treatment of cells and viruses with neuraminidase, ribonuclease or with reagents reacting with amino‐groups, did not demonstrably affect adsorption, which was also apparently insensitive to calcium concentration.

The results may be interpretable in terms of structural microheterogeneity of the surfaces of the cells and/or virus particles.
Effect of combination treatment with cyclophosphamide and isogeneic or allogeneic spleen and bone marrow cells in leukemic (l1210) mice
Authors: Vadlamudi S. , Padarathsingh M. , Bonmassar E. , Goldin A.
Published: February 2007

Generalized leukemia was observed on day 3 following intra‐peritoneal inoculation of leukemic (L1210) ascites cells in CDF1 mice. On day 3 after tumor implantation, residual viable leukemic cells were detected in the peritoneal cavities and spleens of leukemic mice 6 h following treatment with 180 mg/kg of cyclophosphamide. Mice receiving weekly intraperitoneal injections of X‐irradiated leukemic (L1210) cells for 6 weeks were resistant to a challenge of tumor cells. When incubated in vitro, spleen and bone marrow cells of immune mice were able to inactivate viable leukemic cells, as evidenced by failure of tumor growth in mice inoculated with these cells. Leukemic mice injected with immune spleen or bone‐marrow cells from isogeneic mice following treatment with cyclophosphamide survived a 60‐day observation period. In one such experiment 90‐day survivors were able to resist re‐inoculation of tumor cells. Leukemic (DBA/2) mice inoculated with allogeneic spleen cells following cyclophosphamide treatment survived for longer periods than mice injected with isogeneic spleen cells.
Immunofluorescent study of alpha‐foetoprotein (αfp) in liver and liver tumours. II. Localization of αfp in the tissues of patients with primary liver cancer (PLC)
Authors: Goussev A. I. , Engelhardt N. V. , Masseyeff R. , Camain R. , Basteris B.
Published: February 2007

Localization of αfp independent of the presence of serum was demonstrated only in a limited number of tumour cells in αfp‐positive hepatocellular carcinomas. These cells usually formed three‐dimensional groups with a definite tendency to localize near blood vessels and capillaries. Haematoxylin‐eosin staining did not reveal any morphological difference between αfp‐positive and ‐negative tumour cells.
Isoenzyme and protein profiles of normal, leukemic and fetal mouse tissues
Authors: Tyndall R. L. , Allen R. C. , Friedman E. , Moore D. J.
Published: February 2007

Electrophoretic characterization of extracts from normal, leukemic and fetal mouse tissues indicated that infection with RLV results in the subsequent emergence of cells having profiles similar to fetal thymus and spleen tissues. Microdensitometric analyses showed diminution of prealbumin and haptoglobin esterase activity with concomitant predominance of postalbumin esterase activity in both fetal and leukemic thymus and spleen tissues. Both JLS V9 and JLS V6 infected cell cultures showed marked enhancement of postalbumin esterase activity. Leukemic and fetal thymus and spleen tissues also showed increased activity in LDH isoenzyme V, relative to the total LDH activity, compared to normal adult tissues. Increased relative activity in Band V LDH was also noted in infected V6 cells compared to uninfected cells. Increased amounts of proteins with electrophoretic mobilities similar to serum albumin and transferrin were evident in extracts of fetal and leukemic thymus and spleen tissues. Protein profiles of purified RLV showed a predominant band migrating similarly to serum albumin with minor bands migrating similarly to serum transferrin and haptoglobin.
Studies on friend virus‐induced viremia in lethally irradiated mice with or without hematopoietic repopulation
Authors: Rossi G. B. , de Harven E. , Haddad J. R. , Friend C.
Published: February 2007

No detectable viremia was recovered from supralethally irradiated mice which had been infected with Friend Leukemia Virus (FLV) although large amounts of virus were recovered from non‐irradiated control mice.

When irradiated mice were repopulated with either spleen or bone‐marrow cells from syngeneic donors and then infected with FLV, viremia was readily detectable in these hosts, both by electron microscopy and by bioassay into susceptible mice. In similarly irradiated mice given thymus cells, however, no virus was detected by titration although extremely rare particles were observed in the plasma pellets examined by electron microscopy.

These data indicate that the appearance of virus in the plasma depends upon the presence in the infected animals of FLV target cells, found primarily to be the hematopoietic components of both bone marrow and spleen.
Concomitant immunity in hamsters bearing syngeneic transplants of tumors induced by para‐adenovirus 7, simian adenovirus 7, or 9,10‐dimethylbenzanthracene
Authors: Lausch Robert N. , Rapp Fred
Published: February 2007

Studies in an inbred line of hamsters have revealed that animals bearing tumor transplants reject a second graft of the same cells. This resistance was specific and was manifested against tumor cells induced by viruses (PARA‐adenovirus 7, simian adenovirus 7) or chemicals (9,10‐dimethylbenzanthracene). Studies designed to measure dose‐response revealed that tumor‐bearing hamsters were 10 to more than 100 times as refractory to challenge by a given cell line as were normal hamsters. Nevertheless, this immunity did not prevent continued growth of the primary transplant.