bluuebunny/crossref_metadata_2025 huggingface dataset:
Failure to induce cervical cancer in mice by long‐term frequent vaginal exposure to live or inactivated herpes simplex viruses
Authors: Meignier Bernard , Norrild Bodil , Thuning Claire , Warren Joel , Frenkel Niza , Nahmias Andre J. , Rapp Fred , Roizman Bernard
Published: February 2007

C57 mice aged 8–10 weeks in groups of 50 each received vaginal cotton pellets soaked in lysates of HEp‐ 2 cells, either mock‐infected or infected with herpes simplex virus I, herpes simplex virus 2, and highly attenuated recombinant viruses 5 times a week for 89 to 114 weeks. An untreated group was also included. The mock‐infected and some of the infected cell lysates were exposed to ultraviolet light at a dose sufficient to inactivate virus. Smears of exfoliated vaginal cells collected once a month and histopathologic sections of genital organs removed at autopsy were coded and examined blind for the presence of abnormal cells indicative of malignant changes and cervical cancer, respectively. Sera collected before termination of the study were tested blind for the presence of antibody to infected cell lysates and to purified herpes simplex virus glycoprotein B. The results were as follows: (i) Over 74% of 826 mice examined at autopsy contained tumors at non‐genital sites. The tumors were randomly distributed among the various groups, (ii) Gross genital abnormalities were less common in untreated animals than in mice receiving vaginal implants, (iii) The fraction of mice which developed cervical cancer diagnosed by histopathologic examination was small (7.2%) and not significantly different among various groups, (iv) There was no correlation between the presence of abnormal exfoliated cells indicative of early invasive or invasive cancer lesions and the histopathologically proven diagnosis of micro‐invasive or invasive cervical cancer, (v) The incidence and levels of antibody were highest in animals exposed to live virus; some mice exposed to inactivated virus also developed weak or moderately high antibody levels. The presence of antibodies did not correlate with the presence of histopathologically proven cervical cancer. The results do not support the ability of herpes simplex viruses to cause genital neoplasia in mice.
Analyses of transplanted murine tumors for HSV DNA sequences
Authors: Yehiely Fruma , Thuning Claire , Meignier Bernard , Norrild Bodil , Warren Joel , Nahmias Andre J. , Rapp Fred , Roizman Bernard , Frenkel Niza
Published: February 2007

Meignier et al. (1986) report the results of exposure of C57BL/6NCr mice to vaginal plugs containing live or inactivated herpes simplex virus 1 or 2 (HSV‐1 or HSV‐2) or recombinant viruses 5 times a week for up to 114 weeks. Genital organs showing abnormalities were transplanted into nude mice. Of 33 transplants, 13 produced subcutaneous tumors in nude mice and 12 were subsequently transplanted into C57BL/6NCr mice. We report that the DNA extracted from coded tumor tissues of nude mice and from normal viscera of the same rodents did not hybridize with HSV‐1 and HSV‐2 DNA probes representing the viral genomic regions shown previously to be capable of morphologically transforming cells in culture. The sensitivity of the assays was such that we could detect 0.5 copies of the HSV sequences of complexity equal to or greater than 1 Kbp per cell DNA equivalent. To control for the sensitivity of the assays in the actual hybridizations, the tumor‐cell DNA was also hybridized with a β‐globin mouse DNA probe. A striking feature of these control hybridizations was the detection of β‐globin polymorphism in some nude mouse tumors. The β‐ globin polymorphism allowed us to conclude that the analyzed tissues contained significant amounts of the tumor cells occurring in the C57BL/6NCr mice.
cAMP metabolism in B16 melanoma clones during the formation of experimental and spontaneous metastases
Authors: Lester Bruce R. , Greig Russell G. , Buscarino Charles , Sheppard Jack R. , Corwin Steven P. , Poste George
Published: February 2007

The ability of B16 melanoma clones to form tumor colonies in the lung after i.v. injection (experimental metastases) correlates positively with their capacity to respond to activators of cyclic adenosine 3‐, 5‐ monophosphate (cAMP) metabolism (such as melano‐ cyte‐stimulating hormone and forskolin). To investigate whether this relationship is causal, the cAMP responses of 4 B16 melanoma clones of differing colonizing potential have been examined in freshly established stock cell cultures, in pulmonary colonies in vivo and in cultures established from these lesions. In all cases, the cAMP responsiveness of the excised colonies (and cultures derived from them) mimicked the responsiveness of the cultures from which they arose. B16 clones exhibiting low cAMP responsiveness gave rise to few experimental metastases all of which were poorly responsive to activators of cAMP metabolism. Similarly, clones with high cAMP responsiveness formed multiple lung colonies which displayed a marked sensitivity to agents that stimulated cAMP production. Parallel experiments on the spontaneous metastatic behavior of the same clones revealed that the cAMP responsiveness of cells in the primary (intra‐ footpad) tumor and spontaneous metastatic lesions in the lung faithfully reflected the response profile of the original tumor‐cell inoculum but no correlation was found between cAMP responsiveness and the capacity to form spontaneous metastases. These data suggest that cAMP‐dependent events may influence the survival, arrest and organ colony formation by cells injected directly into the circulation but appear to be of little or no importance in determining the early event(s) involved in the evolution of spontaneous metastases prior to the entry of cells into the circulation.
Density distributions of human squamous carcinoma cells: Influence of growth conditions, proliferative status and DNA content
Authors: Ng C. E. , Keng P. C. , Sutherland R. M.
Published: February 2007

Human squamous carcinoma cells (A43I, CaSki) were grown in vitro as multicellular spheroids or as exponential and plateau‐phase monolayer cultures. Single‐cell suspensions were obtained by disaggregating the spheroids and monolayer cultures with trypsin‐EDTA. Their buoyant density distributions were then compared by centrifuging the suspensions for 30 min at about 800 gave and 4°C in linear, continuous Percoll gradients. We found differences in buoyant density related to the growth condition (i.e. cells grown as spheroids or plateau‐phase cultures were more dense than those from exponential cultures) and to the cell‐line (i.e. CaSki cells were more dense than the A43I cells). Cells isolated from the inner layers of the spheroids appeared to be less dense than those from the outer layers. In addition, quiescent cells separated from the A431 spheroids by centrifugal elutriation, a technique based on cell size, were more dispersed in buoyant density than the corresponding proliferating cells recovered from the same spheroids. Flow cytometric analysis with mithramycin was performed to measure the DNA content of the cells. We found that the CaSki cells contained relatively more DNA than the A431 cells whereas, for the same cell line, growth as monolayer cultures or as multicellular spheroids did not influence their relative DNA content. We conclude that the growth conditions, the proliferative status of the cells and possibly their relative DNA content may influence the density distribution of these cells.
Interactions with host macrophages and ability of human melanoma cell lines to grow in nude mice
Authors: Benomar Abdeljalil , Gerlier Denis , Doré Jean‐Franc̨ois
Published: February 2007

The interactions of nude mouse macrophages with five human melanoma cell lines, characterized by their resistance to mouse NK activity and varying in their ability to grow s.c. in nude mice, were investigated. These lines were equally susceptible in vitro to both cytostatic and tumoricidal activities of activated peritoneal macrophages collected from nude mice inoculated 3 days previously with Brucella abortus B19R strains, I.p. injection of a poorly tumorigenic melanoma cell line (PTCL) in nude mice was followed by the local appearance of macrophages able to kill these cells in a 48‐hr 3H‐thymidine cytotoxicity assay. The level of tumoricidal macrophages was maximum for the first week and then slowly declined to disappear by the 4th week following PTCL inoculation. The use of an HTCL instead of a PTCL also induced macrophages able to kill HTCL cells, but the cytotoxicity level was lower and the activity disappeared more rapidly. In cross‐experiments using PTCL‐activated macrophages as effectors on HTCL targets, these cells were found to be less sensitive than PTCL cells when macrophages were taken at weeks 2 and 3 following PTCL inoculation. To investigate whether tumoricidal macrophages activated In vivo with human melanoma cells could also act in vivo, we inoculated these s.c. into nude mice, simultaneously with live HTCL cells. Peritoneal cells rich in melanoma‐activated macro‐phages prevented HTCL growth in most recipients, whereas spleen cells from the same donor mice did not modify the tumor take. These data indicate that xenogeneic tumors could activate nude mouse macrophages in vivo and suggest that the ability of human tumors to grow in nude mice could be related to their capacity to activate host macrophages locally and to the susceptibility of human tumor cells to the tumoricidal activity of activated macrophages.
Epstein‐barr virus‐related herpesvirus from a rhesus monkey (Macaca Mulatta) with malignant lymphoma
Authors: Rangan S. R. S. , Martin Louis N. , Bozelka Brian E. , Wang Nancy , Gormus Bobby J.
Published: February 2007

A herpesvirus (RhEBV) was isolated from a lympho‐blastoid cell line (LCL) that became established from a malignant lymphoma in a rhesus monkey. The predominant cell marker in the LCL was that of B lymphocytes. RhEBV‐induced viral capsid (VCA) and nuclear antigens (NA) in the LCL were serologically related to similar antigens known to be induced by human Epstein‐Barr virus (EBV). RhEBV was of non‐human primate origin and was clearly differentiated from EBV in the anti‐complement immunofluorescence reaction using human and non‐human primate sera with antibodies to the NA induced by the respective viruses. While human sera reacted with NA induced by both EBV and RhEBV, monkey sera failed to recognize the NA induced by EBV. RhEBV‐induced NA was present in nearly all the cells of a suspension prepared from the tumor tissue mass, but not in the monolayer fibroblasts derived from the tumor tissue or in the blood and lymph‐node lymphocytes of clinically healthy animals. RhEBV induced in vitro transformation and establishment of LCLs from peripheral blood lymphocytes of normal rhesus and cynomolgus monkeys but not from those of 6 other non‐human primate species tested. The LCLs, with predominant B‐lymphocyte markers, established after treatment with RhEBV, all had evidence of the virus infection since nearly all cells in the culture expressed the virus‐induced NA.
Characterization of melanoma‐associated surface antigens involved in the adhesion and motility of human melanoma cells
Authors: de Vries Jan E. , Keizer Gerrit D. , Te Velde Anje A. , Voordouw Arie , Ruiter Dirk , Rümke Philip , Spits Hergen , Figdor Carl G.
Published: February 2007

The functional properties of the melanoma‐associated antigens detected by monoclonal antibodies (MAbs) AMF‐6 and AMF‐7 were investigated. These MAbs were selected previously because of their capacity to block the anti‐melanoma reactivity of cytotoxic T‐lymphocyte clones AMF‐6 and AMF‐7 detect a melanoma‐associated proteoglycan (MW > 450–250 kDa) and a molecular complex, which under reducing conditions consists of 4 compounds of 120, 95, 29 and 25 kDa respectively. AMF‐6 reacted strongly with all 30 cultured melanomas and all 41 melanomas in frozen tissue sections. Significant cross‐reactivity was only observed with nevi and perineurium, whereas normal skin melanocytes were negative. AMF‐7 reacted with all 25 cultured melanomas and all 34 melanomas in frozen sections. AMF‐7 cross‐reacted with a proportion of nevi and endothelial cells from small vessels. The antigen detected by AMF‐6 and AMF‐7 could not be modulated by retinoic acid or recombinant 7‐IFN, which induced or enhanced the expression of HLA‐DR, HLA‐DQ and Class‐I MHC antigens. In addition, the antigens were not readily modulated when cells were incubated in excess amounts of AMF‐6 and AMF‐7. Interestingly, the antigen detected by AMF‐7 was strongly associated with the adhesion and cytoplasmic spreading of melanoma cells to plastic surfaces and monolayers of vascular endothelial cells. AMF‐6 did not block the adhesion of melanoma cells but delayed cytoplasmic spreading. Both AMF‐6 and AMF‐7 blocked fibronectin‐induced chemotaxic motility and chemokinesis of melanoma cells. In addition to their membrane localization, the antigens detected by AMF‐6 and AMF‐7 were also abundant in extracellular adhesion plaques deposited by cultured melanoma cells.

Our results indicate that the high‐MW melanomaassociated proteoglycan and the antigen detected by AMF‐7 are associated with adhesion and/or cytoplasmic spreading and motility of human melanoma cells, suggesting that these antigens are associated with the (hematogenic) dissemination of human melanoma. This is supported by the finding that AMF‐7 stained primary tumors heterogeneously, whereas metastases were homogeneously stained.
Monoclonal antibody G 250 recognizes a determinant present in renal‐cell carcinoma and absent from normal kidney
Authors: Oosterwdk E. , Ruiter D. J. , Hoedemaeker Ph. J. , Pauwels E. K. J. , Jonas U. , Zwartendijk I. , Warnaar S. O.
Published: February 2007

This report describes a monoclonal antibody designated G 250, subclass IgGI, that recognizes an antigen preferentially expressed on cell membranes of renalcell carcinoma cells (RCC) and not expressed in normal proximal tubular epithelium. G 250 antibody reacted with 46 of 47 primary RCC, with 7 of 8 RCC metastases and with a few other malignant tumors. The staining pattern of G 250 differs from that of other RCC‐related antibodies described. Preliminary experiments show that this antibody can be used to visualize RCC xenografts in nude mice by immunoscintigraphy.
Synergism of recombinant human interferon gamma with liposome‐encapsulated muramyl tripeptide in activation of the tumoricidal properties of human monocytes
Authors: Sone Saburo , Tandon Priti , Utsugi Teruhiro , Ogawara Mitsumasa , Shimizu Eiji , Nii Akihiko , Ogura Takeshi
Published: February 2007

Freshly isolated human peripheral blood monocytes from healthy volunteers are not cytotoxic to allogeneic A375 melanoma cells, but they were rendered tumoricidal by incubation in vitro with either liposomes containing 5 μg/μtmol phospholipid of muramyl tripeptide phosphatidylethanolamine (liposome‐MTP‐PE; optimal dose, 500 nmol/ml) or recombinant human interferon gamma (rIFN‐γ; optimal dose, 100 U/ml). A combination of sub‐threshold concentrations of liposome‐MTP‐PE (50 nmol/ml) and rIFN‐γ (1 or 10 U/ml) also induced significant tumor‐cell killing, indicating that the effects of rIFN‐γ and liposome‐MTP‐PE in monocyte activation are synergistic. In contrast to rIFN‐γ, recombinant INF‐α and IFN‐β had additive effects with liposome‐MTP‐PE in human monocyte activation. Since recombinant human IFN‐γ has a synergistic effect with liposome‐MTP‐PE in monocyte activation, unlike IFN‐α or IFN‐β, and liposome‐MTP‐PE as well as rIFN‐γ is available at standardized concentrations, this combination could be of clinical value in the treatment of disseminated malignant disease.
Somatic rearrangement of the c‐myc oncogene in primary human diffuse large‐cell lymphoma
Authors: Chenevix‐Trench Georgia , Behm Frederick G. , Westin Eric H.
Published: February 2007

Chromosome translocations involving 8q24, the band to which c‐myc has been mapped (Dalla‐Favera et al., 1982), are a uniform finding in Burkitt's lymphoma (Bernheim et al., 1981). However, in only a minority of the tumors is the rearrangement of the c‐myc locus sufficiently close to the gene to be detected with currently available probes (Dalla‐Favera et al., 1983). Approximately 25% of diffuse large‐cell lymphomas have also been reported to have translocations involving 8q24 (Mitelman, 1985), but there have been no reports of c‐myc rearrangements in this form of non‐Hodgkin's lymphoma. We have examined the structure of the c‐myc locus in primary tumor tissue of 10 cases of diffuse large‐cell lymphoma. In one patient, Southern blot analysis revealed additional c‐myc fragments in the tumor DMA but not in the germ‐line DNA. Southern blot analysis using probes from both the heavy‐and light‐chain immunoglobin loci showed that the myc rearrangement was unlikely to involve the immunoglobulin loci in this patient.
Reversible inhibition of lymphokine‐activated killer cell activity by lipoxygenase‐pathway inhibitors
Authors: Sibbitt Wilmer L. , Imir Turgut , Bankhurst Arthur D.
Published: February 2007

Natural killer (NK) cells and lymphokine‐activated killer (LAK) cells are anomalous cytotoxic cells which are potentially important in host defense against cancer. Several studies have demonstrated that natural killer (NK) cell activity can be suppressed by chemical inhibitors of the lipoxygenase pathway through inhibition of the production of leukotriene B4 (LTB4). The present study investigated the effects of the lipoxygenase inhibitors BW755C and nordihydroguaiaretic acid (NDGA) on NK and LAK cell activity. NK cell function of fresh peripheral blood mononuclear cells (PBMC) was determined via a standard chromium release assay employing K562 as the tumor target. The LAK cell activity of PBMC which had been stimulated with 10 IU of interleukin‐2 for 72 hr was determined against the NK‐resistant cell line Oaudi. Both BW755C and NDGA inhibited NK and LAK cell function at a variety of concentrations. Indomethacin, a prostaglandin synthesis inhibitor, did not bring about an appreciable diminution in NK or LAK cell activity. Inhibition of NK and LAK cell activities by BW755C and NDGA could be reversed by washing the effector cell suspensions prior to the cytotoxic assay or by adding LTB4(10−11–10−8 M) directly to the effectortarget suspensions. These data indicate that certain arachidonic acid oxidation products of the lipoxygenase pathway are essential for the function of LAK cells.
Epstein‐barr virus‐related ultrastructural modifications of plasma membrane during B‐cell transformation
Authors: Arancia G. , Ragona G. , Rocchi G. , Donelli G.
Published: February 2007

Ultrastructural modifications are described in the plasma membrane of in vitro established human B cells. By the freeze‐fracture technique, intramembrane particles (IMPs) are quantified in B lymphocytes following Epstein‐Barr virus (EBV) transformation in vitro, and in B‐lymphoma (Burkitt‐type) cells, either positive or negative for EBV genome. Analysis shows an overall increase in IMP density as compared to normal controls. Differences are observed between the protoplasmic and exoplasmic faces of fractured membranes as well as among in vitro transformed and clearly neoplastic cells. Results indicate that conformational changes in IMP distribution parallel neoplastic evolution of transformed cells.
Generation of mouse natural killer (NK) cell activity: Effect of interleukin‐2 (IL‐2) and interferon (IFN) on the in vivo development of natural killer cells from bone marrow (BM) progenitor cells
Authors: Riccardi Carlo , Giampietri Antonio , Migliorati Graziella , Cannarile Lorenza , D'Adamio Luciano , Herberman Ronald B.
Published: February 2007

The possible effect of IL‐2, α, β‐IFN and poly I:C (an IFN inducer) administration on the generation of NK cells of LI and BM‐reconstituted animals was investigated. B6D2F, mice were LI (9.5 Gy) by total‐body irradiation and reconstituted by i.v. injection of different doses (ranging from 106 to 2 × 107) of syngeneic BM, after which the levels of splenic NK activity were evaluated on days 4, 7, 9, 12 and 14 after LI and BM graft. After a marked decline on day 4 (no detectable NK activity at any effector to target ratio tested), NK activity gradually returned, reaching the levels of untreated controls on day 9. Groups of LI and BM‐reconstituted mice were also treated i.p. with mouse or human recombinant IL‐2 from day 0 through day 3 (15–50 U/day/mouse) after BM transplantation. It appears that an earlier reconstitution of NK activity occurs in IL‐2‐treated animals as compared to medium‐injected controls. LI and BM‐reconstituted animals were also treated i.p. with α, β‐IFN (104 U/mouse) or Poly I:C (1 mg/kg/mouse) from day 0 through day 3, and the splenic NK activity was evaluated at 4, 7, 9, 12 and 14 days after LI and BM graft. Our data indicate that in vivo administration of IFN or Poly I:C was able to cause an earlier maturation of NK activity as measured on days 7 and 9 after LI. In contrast, when the NK activity of IFN‐treated animals was compared with that of controls 14 days after LI and BM graft, a significant inhibition was found due to the induction of suppressor cells. Pre‐treatment of donor BM with Poly I:C or IFN was also able to induce a more rapid reconstitution of NK activity of recipient mice. The NK activity reconstitution paralleled the increase in the number of splenic LGL. A synergistic effect was obtained when LI mice were transplanted with Poly I:C‐pre‐treated BM and then treated with IL‐2. The effector cell in the IFN and IL‐2 treated chimeras is a typical NK cell: asialo GM‐1+, Thy 1±, Lyt 1−, Lyt 2−and reactive only against NK‐susceptible targets. These data suggest that IL‐2 as well as IFN may represent maturational signals in the in vivo physiological regulation of growth and differentiation of BM NK stem‐cells.
Expression of LY‐6.2 and Thy‐1 antigens on NIH 3T3 cells suppressed after transformation with activated human ras‐oncogenes
Authors: Ivanyi Dagmar , Janssen Johannes W. G. , Collard John G.
Published: February 2007

We have studied the expression of several cell surface antigens in NIH 3T3 cells after neoplastic transformation with activated human ras and myc oncogenes. The binding of monoclonal antibodies (MAbs), specific for mouse differentiation antigens Ly‐6.2, Thy‐1 and 9F3, to normal and transformed cells was assessed using a fluorescence‐activated cell sorter (FACS IV). Significant reduction of Ly‐6.2 and Thy‐1 antigen expression was detected in cells transformed with either the N‐ras, Ki‐ras or H‐ras oncogenes but not in c‐myc transfected cells. 9F3 antigen expression remained at the original high level in all transfectants studied. Normal levels of Ly‐6.2 and Thy‐1 expression reappeared in revertants derived from: unstable ras‐transfectants. These data indicate that ras sequences did not preferentially transform cells that were deficient in Ly‐6.2 and Thy‐l antigens. It was also shown that the reduced binding of anti‐Ly‐6.2 antibodies to ras‐transfectants was not due to a masking effect of increased cell‐surface sialylation occurring in ras‐transfected cell lines. Other possible explanations of the detected phenotypic changes are discussed. The results extend the range of tumor‐associated membrane alterations in NIH 3T3 cells following transfection with human tumor DNA containing activated ras oncogenes by a hitherto unreported alteration in the expression of Ly‐6 and Thy‐1 antigens.
Development of quantitative liquid competition radioimmunoassays for the ras oncogene and proto‐oncogene p21 products
Authors: Caruso Arnaldo , Schlom Jeffrey , Vilasi Vincent , Weeks Maureen O. , Hand Patricia Horan
Published: February 2007

The ras gene family of rodents and humans is highly conserved and consists of several distinct genes, i.e., rodent Harvey and Kirsten, and human Harvey, Kirsten and neuroblastoma. This gene family mediates transformation via (1) a point‐mutation resulting in the change of one amino acid in the 21 kDA ras gene product (p21) or (2) increased expression of ras p21. Group‐specific, type‐selective and interspecies indirect binding liquid competition radioimmunoassays (RIAs), capable of providing truly quantitative analyses of the 21 ras oncogene and protp‐oncogene products, have been developed. Using purified recombinant ras p21 from Escherichla coli expressing the full‐length T24 mutant human Harvey‐ras gene protein product as a standard in these RIAs, we have defined the absolute numbers of pg, fM and molecules of ras p21 in: (1) E. coli expressing the point‐mutated or proto‐ras p21 and (2) mammalian cell lines of human and murine origin. Two of the RIAs developed can be termed group‐specific in that they have the ability to detect the point‐mutated and proto forms of all 3 human ras genes (Harvey, Kirsten, and neuroblastoma), while the third RIA is type‐selective, since it detects an antigenic determinant located primarily on the Harvey ras p21. All 3 RIAs are interspecies‐specific since they are able to detect ras p21 in rodent as well as human cells. The adaptability of the RIAs to various assay conditions and ease of methodology make these immunoassays applicable to the study of several parameters associated with ras p21 expression. These assays, used in conjunction with specific cDNA probes to identify specific ras proto‐oncogenes or point‐mutated oncogenes being expressed, now provide truly quantitative analysis of ras p21 in mammalian cells to further the study of the association between ras p21 expression and transformation.
Binding of oestradiol to blood proteins and aetiology of breast cancer
Authors: Moore J. W. , Clark G. M. G. , Hoare S. A. , Millis R. R. , Hayward J. L. , Quinlan M. K. , Wang D. Y. , Bulbrook R. D.
Published: February 2007

A prospective study of 5,000 women has shown that, compared to controls, those who subsequently developed breast cancer had a higher proportion of their blood oestradiol in the non‐protein‐bound and albumin‐bound fractions (the bio‐available fraction) and a lower proportion in the sex‐hormone‐bound fraction. The increased proportion of bio‐available oestradiol was partly due to a lower concentration of sex‐hormone‐binding globulin. Weight was excluded as a confounding factor.
Characterization and chromosomal assignment of a human cell surface antigen defined by the monoclonal antibody AUAI
Authors: Spurr N. K. , Durbin H. , Sheer D. , Parkar M. , Bobrow L. , Bodmer W. F.
Published: February 2007

We describe the chromosomal assignment and biochemical characterization of the genetic locus controlled by a human cell surface antigen which is defined by the monoclonal antibody (MAb) AUAI. This gene product is only expressed on epithelial cells. Therefore, human‐mouse somatic cell hybrids of epithelial origin were used to assign this gene to chromosome 2. Cell surface iodination of the hybrids and parental cells followed by immunoprecipitation and polyacrylamide gel electrophoresis showed that AUAI detected a single 35‐kDa protein. The MAb AUAI reacted on tissue sections with a subset of normal epithelial cells, but in tumours it showed a much wider distribution, though still only on epithelium‐derived tumours.
Androgen, estrogen, and progesterone receptor levels in malignant and benign breast tumors: A multivariate analysis approach
Authors: Brentani Maria Mitzi , Franco Eduardo Luis , Oshima Celina Tizuko F. , Pacheco Mercia Medeiros
Published: February 2007

Androgens have been frequently used in the treatment of breast cancer. However, objective responses seem to vary according to the steroid hormone receptor expression of the tumor. We have studied the relationship between concentrations of androgen receptors (AR) and those of estrogen (ER) and progesterone (PR) receptors by multiple regression and stratified analysis techniques in 154 cases of primary breast carcinomas and 39 cases of benign tumors. Both the proportion of AR‐positive tumors and the concentration of AR were dependent upon the coexpression of ER and PR by the specimens. This association was evident for malignant tumors with predominance of the positive correlation between AR and ER over that of AR and PR in post‐menopausal patients. In premenopausal women, ER and PR concentrations were similarly correlated with AR levels. The PR, but not the ER concentration, was positively correlated to AR levels in benign breast tumors. These findings were confirmed by multiple regression, taking into consideration additional information about the patients to build statistical models allowing prediction of AR. Among the other variables considered in building these models—age, menopausal status, weight, height, and clinical stage—only height (using data from all patients) and age (data from post‐menopausal women) emerged in addition to ER and PR as significantly explaining the variability of AR as the dependent variable.
Evidence for HTLV‐III/LAV expression by primary cultures of T8 cells
Authors: Fouchard M. , Reveil B. , Mbayo K. , Lurhuma A. , Sarin P. S. , Gallo R. C. , Zagury D.
Published: February 2007

The selective targets for HTLV‐III/LAV, the causal infectious agent of AIDS and AIDS‐related complex (ARC), are T4 cells, apparently because the virus receptor is associated with T4 antigen determinants. This accounts for T4 cell depletion in AIDS and for a decrease of IL‐2 production by AIDS peripheral blood lymphocytes (PBL) after in vitro PHA activation. By contrast, T8 cells are not targets for HTLV‐III/LAV, since T8 cells from PBL and from long‐term cultured T cells (CTC) could not be infected by the virus. We describe 2 samples of PBL from Zairian patients with HTLV‐III infection in which HTLV‐III was expressed by T8 cells. Evidence that T8 cells were expressing virus was obtained by complement cytotoxicity experiments performed in the presence of OKT8 monoclonal antibody (MAb), which removed HTLV‐III‐positive cells from cultured T cells producing the virus, and by double labelling experiments, in which some cells exhibit both T8 antigens detected either by IFA (rhodamine) or by rosetting in presence of OKT8 MAbs and HTLV‐III antigens detected by IFA (fluorescein) with of anti‐HTLV‐III p24 and p15 MAbs. Since normal T cells have previously been shown to undergo antigenic diversity, we think these results can be explained by HTLV‐III infection of T4 cells which later lost T4 antigens and acquired the T8 phenotype.
Immunoresistant metastatic tumor variants can re‐express their tumor antigen after treatment with DNA methylation‐inhibiting agents
Authors: Altevogt P. , von Hoegen P. , Schirrmacher V.
Published: February 2007

Immuno‐escaping variants which arise during metastasis of ESb lymphoma cells in syngeneic DBA/2 mice have been shown to exhibit selective resistance to lysis by ESb‐specific cytotoxic T‐lymphocytes (CTL). The immuno‐resistant variants present no changes in the expression of H‐2Kd molecules which appear to be the restricting elements for ESb‐specific CTL. We now show that treatment of clonal immuno‐resistant ESb variant cells with MNNG or 5′azacytidine can restore the sensitivity to tumor‐specific CTL lysis in a high percentage of cloned progenitor cells. The acquisition of susceptibility to lysis by these clones is most likely due to re‐expression of ESb‐type tumor antigens because such cells (i) regain the capacity to compete with original 51Cr‐labelled ESb cells for lysis by ESb‐specific CTL, and (ii) regain the capacity to induce ESb‐specific CTL in vivo. Our data suggest that the immuno‐resistant variants are not cellular mutants but rather gene regulatory variants. This could explain: (i) their high frequency of occurrence during metastasis; (ii) the relative stability of the variant phenotype; and (iii) the reversibility observed after the use of DNA‐demethy‐lating and gene‐activating drugs like 5′‐azacytidine or MNNG.
Relationship between cellular levels of beta‐carotene and sensitivity to genotoxic agents
Authors: Stick Hans F. , Dunn Bruce P.
Published: February 2007

The usefulness of an in vitro test system to predict the inhibitory effect of beta‐carotene on the genotoxic activity of carcinogens/mutagens was explored. To facilitate the comparison of data obtained from cultured cells (CHO) and from exfoliated human cells, end‐points were used which can be quantitated in both cell systems: the frequency of micronuclei for estimating the effect of genotoxic agents, and cellular levels of beta‐carotene as a protective agent. In CHO cells, beta‐carotene inhibited the clastogenic and micronu‐cleus‐forming effect of methyl methanesulfonate (MMS) and 4‐nitroquinoline‐l‐oxide (4NQO), but had no protective action against gallic acid, tannic acid, an aqueous extract of areca nut or H2O2. The extent of inhibition depended on the ratio of beta‐carotene to MMS. Doses of beta‐carotene which exerted a protective effect in vitro ranged from approximately 2 to 5 ng per 106 CHO cells. Comparable levels of beta‐carotene were previously found to reduce the frequency of micronucleated exfoliated cells from the buccal mu‐cosa of tobacco and areca‐nut chewers (Stich et al., 1984b).
Rearrangement of c‐myc, pim‐1 and Mlvi‐1 and trisomy of chromosome 15 in MCF‐ and moloney‐MuLV‐induced murine T‐cell leukemias
Authors: Wirschubsky Zvi , Tsichlis Philip , Klein George , Sumegi Janos
Published: February 2007

Provirus insertion near the c‐myc, pim‐1 or MIvi‐I genes occurred in 7 out of 59 virally induced T‐cell leukemias. C‐myc was exclusively rearranged in approximately 10% of MCF 247‐induced tumors while MIvi‐I was rearranged to a similar frequency in Molo‐ney‐virus‐induced lymphomas. Out of 25 karyotyped tumors, 9 (36%) showed trisomy of chromosome 15. Provirus insertion near c‐myc, pim‐I or MIvi‐I occurred both in diploid lymphomas and in tumors with trisomy 15. These results suggest that the molecular and cytogenetic changes observed in murine T‐cell leukemias are independent tumor‐associated events and that trisomy of chromosome 15 is a common tumor‐progression‐related event.
In vivo anti‐tumour activity of recombinant human and murine TNF, alone and in combination with murine IFN‐γ, on a syngeneic murine melanoma
Authors: Brouckaert Peter G. G. , Leroux‐Roels Geert G. , Guisez Yves , Tavernier Jan , Fiers Walter
Published: February 2007

TNF, a protein released by induced macrophages, is believed to mediate, at least in part, the tumoritoxic effects of activated macrophages. In vitro, it has cyto‐toxic effects on transformed cells but not on normal cells, and in vivo it causes necrosis of tumours. Recently, both human and murine TNF became available as pure recombinant proteins. Subsequent work confirmed its in vitro cytotoxic activity, selective for transformed cells, and revealed other, non‐cytotoxic effects on some normal cells. In vitro, the B16BL6 melanoma cells, syngeneic with C57BL6 mice, are resistant to the cytotoxic effects of rTNF but become sensitive when they are also treated with rIFN‐γ. We report that established, s.c. B16BL6 tumours in vivo can be induced to necrotize and regress by a combined systemic treatment with rTNF and murine rIFN‐γ. Although TNF is not species‐specific in vitro, the effects of treatment with human and murine rTNF in vivo are different: with murine rTNF, the synergism with rIFN‐γ is relatively less clear, the addition of IFN‐γ is not necessary to induce regression, toxicity is more pronounced and additional mechanisms of tu‐moritoxicity could be involved. Relapses are frequent but complete cures have been observed. These results give further evidence in favour of a potential clinical use of TNF in combination therapy, e.g. with IFN‐γ. However, there is still a need to develop better regimens, especially for consolidation, and to continue research in order to understand and limit the toxicity, which could be mediated by the activating effects of TNF on some normal cell types.
Ethnic composition, age and sex, together with location and standard of housing as determinants of HLTV‐I infection in an urban trinidadian community
Authors: Miller George J. , Pegram Susan M. , Kirkwood Betty R. , Beckles Gloria L. A. , Byam Neville T. A. , Clayden Susan A. , Kinlen Leo J. , Chan Li C. , Carson Deborah C. , Greaves Melvyn F.
Published: February 2007

The presence of antibody to human T‐cell leukaemia virus (HLTV‐I) has been assessed in 2,143 men and women who represent 83% of all adults aged 35 to 69 years resident in a defined urban community in Trinidad. Individuals of African descent had a higher sero‐positivity rate (7.0%) than those originating from India (1.4%), Europe (0%) or of mixed descent (2.7%). Women were infected more frequently than men, and the prevalence of infection increased with age in both sexes. Sero‐positivity rates were significantly increased in adults who lived in housing of poor quality (p<0.001) or close to water courses (p< 0.025). These data and others raise the possibility that one route of HLTV‐I transmission may be via insect vectors under particular domestic circumstances.
Unsuitability of monoclonal antibodies to oncogene proteins for anti‐tumour drug‐targeting
Authors: Embleton M. J. , Habib N. A. , Garnett M. C. , Wood C.
Published: February 2007

Monoclonal antibodies (MAbs) to ras, sis, erb‐B, src, myb and myc oncoproteins were evaluated for their potential to target anti‐cancer drugs to malignant cells. Each antibody was tested for reactivity against both fixed and viable cultured human tumour cells by immunofluorescence, and all reacted against a variety of fixed tumour cell preparations. Reactions were also observed against fixed non‐malignant cells. None, however, reacted significantly with viable cells. Two antibodies (against ras and myc proteins) were tested for their ability to localize to tumour xenografts in nude mice, and conjugates were constructed by linking these antibodies to methotrexate using human serum albumin as an intermediate carrier. Neither antibody localized to tumour in vivo, and the methotrexate conjugates were not significantly cytotoxic for tumour cells in vitro, in contrast to similar conjugates simultaneously prepared with a proven anti‐tumour MAb (791T/36). It was concluded that currently available MAbs to oncogene proteins are not suitable vectors for targeting cytotoxic agents to tumour cells.
A t(8;14)(q24;q11) translocation in a T‐cell leukemia (L1‐all) with c‐myc and TcR‐alpha chain locus rearrangements
Authors: Mathieu‐Mahul Danièle , Sigaux François , Zhu Chen , Bernheim Alain , Mauchauffe Martine , Daniel Marie‐Thérèse , Berger Roland , Larsen Christian‐Jacques
Published: February 2007

Cell lines established from T‐cell leukemias have recently been reported to exhibit a chromosome translocation t(8;14) involving proto‐oncogene c‐myc and the gene of the T‐cell receptor α‐chain(TcR‐α). In this work, we have studied a case of T‐cell leukemia presenting a t(8;14)(q24;q11) translocation that was found in fresh Jeukemic cells taken during relapse, but was absent in cells collected at diagnosis. Hybridization analysis showed that the breakpoint on chromosome 8 was located 3′ to the c‐myc exon 3. A TcR‐α‐specific original probe (D14S7, Mathieu‐Mahul et al., 1985) revealed two differently rearranged patterns in DNA from leukemic cells obtained at diagnosis and during relapse. In contrast, the rearranged TcR‐β‐gene DNA pattern did not change during the course of the disease, indicating that leukemic cells were clonally related. These data indicate that the chromosome breakpoint in 14q11 is situated in the TcR‐α locus. These results suggest that translocations t(8;14) involving TcR‐α and c‐myc genes in T‐cell malignancies are analogous to variant t(2;8) and t(8;22) translocations observed in Burkitt lymphoma. They also establish that the same types of molecular rearrangements due to a t(8;14) (q24;q11) translocation, at first described in T‐cell lines established in culture, also exist in vivo and may play a role in the evolution of the leukemic process.
Tissue expression of the tumor marker CA 50 in benign and malignant pancreatic lesions. A comparison with CA 19‐9
Authors: Haglund Caj , Lindgren Jan , Roberts Peter J. , Nordling Stig
Published: February 2007

The expression of the tumor marker antigen CA 50, defined by the monoclonal antibody (MAb) C 50, was studied by the immunoperoxidase technique in formalin‐fixed, paraffin‐embedded tissue sections from normal pancreata, from pancreata with pancreatitis and from benign and malignant pancreatic neoplasms. The results were compared with those obtained with MAb 1116 NS 19‐9. The C 50 antibody reacts, like the 1116 NS 19‐9 antibody, with sialosylfucosyllactotetraose (corresponding to sialylated blood group antigen Lewisa), but also with another sugar moiety, sialosyl‐lactotetraose. Thirty‐two of 37 well‐to moderately‐differentiated adenocarcinomas and all cystadenocarcinomas were positive for CA 50. The staining was most intense in the apical border of the cells, and in the intraluminal mucus. The number of positive cells was smaller in poorly differentiated adenocarcinomas and only occasional cells were stained in anaplastic carcinomas. In acute and chronic pancreatitis small terminal ducts, centro‐acinar cells and some large ducts stained for CA 50. In normal pancreas only a few small terminal ducts were CA‐19‐9‐positive, whereas both ducts and centro‐acinar cells were C‐50‐positive. Normal pancreatic tissue adjacent to carcinoma usually stained more strongly for CA 50 than the carcinoma, whereas the opposite was true for CA 19‐9. Eight out of 11 CA‐19‐9‐negative carcinomas were CA‐50‐positive. Serous cystadenomas and malignant islet‐cell tumors were focally positive for CA 50, but negative for CA 19‐9. It seems apparent that the C 50 antibody reacts with another determinant than sialylated Lewis3 in CA‐19‐9‐negative specimens, serous cystadenomas and malignant islet‐cell tumors. Serum CA 50 and CA 19‐9 levels were determined in 29 patients with pancreatic cancer. The sensitivity was similar for both markers (76%), and there was a positive correlation between the serum levels. However, there was no correlation between the serum levels and the histological expression of the CA 50 and CA 19‐9 antigens.
Unusual cytogenetic findings in two patients with t(4;11) acute leukemia
Authors: Testa Joseph R. , Misawa Shinichi , Pollak Avrom , Leavitt Richard
Published: February 2007

Unusual cytogenetic findings are described in two patients with acute leukemia and rearrangements involving chromosomes 4 and 11. Both patients had clinical and phenotypic features often found in leukemia with t(4;11)(q21;q23). At initial diagnosis, one patient showed a standard t(4;11) with duplication of the 4q‐translocation derivative. The latter finding has been described previously in a few patients with t(4;11) in association with disease progression. By analogy with the Ph1 chromosome in chronic myelogenous leukemia, duplication of the 4q‐suggests that this derivative is the critical recombinant in the t(4;11). The second patient has a novel complex translocation, t(4;11;15)(q21;q23;q21). Analysis of this variant trans‐location implies that the 11 q + is the consistent chromosome rearrangement in this type of leukemia. The apparent contradiction of the findings in these and other relevant reported cases reviewed here suggests that genes on both the 11q+ and 4q‐recombinant chromosomes are important, in either the etiology or the progression of this disease.
Experimental inoculation of monkeys with autologous lymphoid cell lines immortalized by and producing human T‐cell leukemia virus type‐I
Authors: Nakamura Hideo , Tanaka Yuetsu , Komuro‐Tsujimoto Atsumi , Ishikawa Kohichi , Takadaya Kumiko Iijima , Tozawa Hideki , Tsujimoto Hajime , Honjo Shigeo , Hayami Masanori
Published: February 2007

Cynomolgus monkeys and squirrel monkeys were inoculated with autologous lymphoid cell lines immortalized by and producing human T‐cell leukemia virus type‐1 (HTLV‐I) in order to serve as an animal model of adult T‐cell leukemia (ATL). The autologous cell tines were established from peripheral blood mononuclear cells (PBMC) from each monkey by co‐cultivation with lethally irradiated MT‐2 cells producing HTLV‐I. All of these cell lines, which had monkey karyotypes, grew continuously without addition of interleukin‐2 (IL‐2) and expressed virus‐specific proteins of HTLV‐I and IL‐2 receptor. After inoculation with the autologous cell lines, specific antibodies against HTLV‐I proteins could be detected in their plasma, and transformed HTLV‐I‐infected cells could be recovered from their peripheral blood for at least 6 months. However, no signs of ATL have been observed to date, i.e. 2 years after inoculation.
Vitamin‐K‐dependent proteins in microsomes of primary lewis lung tumors
Authors: Wilson Adrian C. , Fasco Michael J.
Published: February 2007

Microsomes isolated from Lewis lung (LL) primary tumors raised in C57BL/6 mice have been shown to (i) contain a 4‐hydroxycoumarin (warfarin)‐sensitive cycle of vitamin K metabolism which is at least qualitatively similar to that of liver, and (ii) catalyze the incorporation of NaH14 CO3 into endogenous protein in a vitamin‐K hydroquinone‐dependent reaction to produce γ‐carboxyglutamate. As in liver microsomes, LL microsomal reduction of vitamin K 2,3‐epoxide to vitamin K was greatly enhanced by exogenous dithiols such as dithiothreitol, but under identical conditions the former was 10‐fold faster. The R(+) and S(−) warfarin enantiomers were highly and equally effective inhibitors of both the liver and tumor vitamin K 2,3‐epoxide reductases—the average I50 against the tumor enzyme was 0.25 μM. Partially purified reductases isolated by centrifugation of sodium‐cholate‐treated liver and LL tumor microsomes over a discontinuous sucrose gradient were also inhibited by the sulfhydryl reagent N‐ethylmaleimide following their reduction by dithiothreitol. Like the activity of the epoxide reductase, that of the γ‐carboxylase was much lower in tumor than in liver microsomes and was only detectable in microsomes isolated from tumor‐bearing mice previously administered S(−) warfarin. In view of the reported inhibition of LL tumor metastasis by warfarin and diet‐induced vitamin‐K deficiency, vitamin‐K‐dependent proteins may play a role in the spread and/or subsequent growth of LL cells.