bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of an anti‐idiotypic antibody reactive with an antibody defining the epitope R P A P in the muc‐1 epithelial mucin core
Authors: Bashford Jill L. , Adrian Robins R. , Price Michael R.
Published: February 2007

C595 is a murine lgG3 monoclonal antibody (MAb) raised against human urinary mucin. C595 antibody binds to the protein core of the MUC‐1 mucin (the polymorphic epithelial mucin, PEM) which is elevated in tissue and secretions from human breast carcinomas. The antibody defines the tetrameric epitope, R P A P. In the present study, a syngeneic antiidiotypic MAb, 911, was raised in BALB/c mice against the C595 antibody. This lgG2a anti‐idiotypic antibody blocked the binding of C595 to its mucin core antigen. In turn, pre‐blocking of C595 with a 20 amino‐acid mucin core peptide specifically inhibited binding of 911 antibody to C595. Cross‐reactivity of antibody 911 was only observed against the IgM MAb, 789/91, which has the same minimum antibody‐binding epitope as C595, namely, RPAP. Syngeneic and xenogeneic anti‐sera against 911 antibody displayed increased binding to heptameric peptide sequences containing the motif, R P A(P). The anti‐idiotypic antibody 911 therefore appears to recognize a site within or close to the binding site of the C595 antibody and thus carries an internal image of the parental mucin epitope. Consequently, the 911 idiotypic network offers a promising model system to investigate the mechanism of anti‐idiotype‐induced tumour immunity.
De‐regulation of endogenous retrotransposons in mouse mammary carcinomas of diverse etiologies
Authors: Asch Bonnie B. , Asch Harold L. , Stoler Daniel L. , Anderson Garth R.
Published: February 2007

Of the several families of endogenous retrovirus‐like elements present in the mouse genome, only mouse mammary tumor virus has been analyzed for its role in mammary carcino‐genesis. Very little is known about the expression and activities of other retro‐elements in normal and malignant mammary epithelium. We have begun investigating the possible involvement of the 3 retrotransposons, intracisternal A particles (IAPs), murine‐leukemia‐virus‐related (MuLVr) elements, and VL30 sequences, in neoplastic progression of the mammary gland in BALB/c mice. The purpose of the present study was to determine which of these elements was active in primary mammary carcinomas induced by chemical, hormonal and viral agents. Each of these cancers had aberrant expression of at least one of the latter retrovirus‐like components. IAP and/or MuLVr sequences were over‐expressed 3 to 100‐fold in most of the tumors as compared with normal mammary tissue, whereas VL30 expression was markedly decreased by 5‐ to 35‐fold in almost all of the neoplasms. Our results thus demonstrate that substantial changes in the expression of one or more of these 3 families of endogenous retrotransposons are triggered during mouse mammary tumorigenesis, regardless of etiology. Direct involvement of lAPs and MuLVr elements in neoplastic progression by transposition and insertional mutagenesis in the genome of several hematopoietic cell types has already been demonstrated. Their elevated expression in many mammary carcinomas suggests that these retrotransposons may also be potential participants in some pathways of mouse mammary carcinogenesis.
CD30‐antigen‐specific targeting and activation of T cells via murine bispecific monoclonal antibodies against CD3 and CD28: Potential use for the treatment of hodgkin's lymphoma
Authors: Pohl Christoph , Denfeld Ralf , Renner Christoph , Jung Wolfram , Bohlen Heribert , Sahin Ugur , Hombach Andreas , van Lier René , Schwonzen Martin , Diehl Volker , Pfreundschuh Michael
Published: February 2007

Cross‐linking of specific tumor antigens with the T‐cell‐associated CD3 and CD28 antigens can increase IL‐2 secretion, proliferation and antigen‐specific cytotoxicity in resting T cells. This cross‐linking can be achieved effectively by bispecific monoclonal antibodies (BiMAb) with specificity for both the tumor antigen and CD3 or CD28 antigen, respectively. To take advantage of the enhanced activation of CD3 pre‐activated T cells by additional activation via the CD28 antigen, BiMAb OKT3/HRS‐3 with reactivity to both CD3 and the Hodgkin's‐lymphoma‐associated CD30 antigen and the BiMAb 15E8/ HRS‐3 with reactivity to both CD28 and CD30 antigen were generated by hybridoma fusion. Resting T cells, represented by Jurkat cells (CD3+ /CD28+) were specifically activated to produce IL‐2 by co‐cultivation with an EBV‐transformed B‐cell line (LAZ509, CD30+/CD19+) only in the presence of the CD30/ CD28 cross‐linking BiMAb and an additional cross‐linking anti‐CD3/CDI9 BiMAb (OKT3/6A4). Neither the cross‐linking BiMAbs alone nor any combination of the monospecific parental MAbs induced a comparable IL‐2 production by Jurkat cells in the presence of LAZ509. In addition, using a combination of these BiMAbs, an antigen‐dependent cytotoxicity was induced by targeting APC‐depleted peripheral blood lymphocytes to CD30+ L540 cells. T cells, previously specifically activated by CD3/CD30 in the presence of CD30 antigen, were cytotoxic to CD30+ cell lines only after incubation with BiMAb anti‐CD28/ CD30. Neither of the BiMAbs nor any of the parental antibodies induced a comparable effect. Our results indicate that such BiMAbs may offer a new approach for specific immunotherapy of Hodgkin's lymphoma, which takes advantage of cytokine secretion and cytotoxicity of activated T cells.
An in vitro model of ovarian epithelial carcinogenesis: Changes in cell‐cell communication and adhesion occurring during neoplastic progression
Authors: Hoffman Anton G. , Burghardt Robert C. , Tilley Roger , Auersperg Nelly
Published: February 2007

To investigate the cellular mechanisms of ovarian epithelial carcinogenesis, a series of progressively transformed rat ovarian surface epithelial (ROSE) cell lines were developed and studied. Transfection of primary ROSE cells and an immortalized ROSE line (ROSE 199) with the pSV3neo plasmid (SV40 T‐antigen) yielded transformed lines which retained epithelial morphology. In vivo selection of these pSV3neo cell populations resulted in further phenotypic transformation. Transfection of ROSE 199 with pSV2neo/c‐H‐rosEJ (rasEJ p21) resulted in a malignant line which appeared fibroblast‐like and formed invasive sarcomas both in athymic mice and in immunocompetent rats. Gap junctional intercellular communication (GJIC) and cell‐cell adhesion were studied in this series of ROSE lines. Both c‐H‐rasEJ‐transformation and in vivo selection resulted in a significant reduction of GJIC between adjoining cells and a transition of in vitro migration as continuous epithelial sheets to the dissociation of individual cells. This apparent shift in cell adhesiveness was associated with reduced expression of the E‐cadherin adhesion molecule. Our data suggest that neoplastic progression of the ovarian surface epithelium may be associated with concomitant reductions in GJIC, E‐cadherin expression and functional adhesiveness.
An in vitro model of intra‐epithelial expansion of transformed urothelial cells
Authors: Rebel Johanna M. J. , De Boer Willem I. , Thijssen Cornelia D. E. M. , Vermey Marcel , Zwarthoff Ellen C. , Van Der Kwast Theo H.
Published: February 2007

Replacement of normal urothelium by pre‐cancerous epithelium may explain the high recurrence rate of human bladder cancer. An in vitro model was designed in order to study the mechanisms of expansion of transformed urothelial cells at the expense of normal urothelium. For this purpose, mouse bladder explants were allowed to expand on a transparent porous membrane. Subsequently, cell sheets of the non‐tumorigenic mouse urothelial cell line NUC‐5, the tumorigenic mouse urothelial cell line NUC‐5 Py and the human bladder‐carcinoma cell line T24 were inoculated adjacent to the primary explant. Daily measurements of the outgrowth of the bladder explant were performed, and all cultures were terminated on day 24. At this time the post‐confluent primary urothelial cell outgrowths still showed proliferative activity, as demonstrated by bromodeoxyuridine incorporation. In due course the non‐tumorigenic NUC‐5 cells were replaced by the bladder outgrowth. T24 and NUC‐5 Py cells were able to inhibit the bladder outgrowth, or even infiltrate or replace the explant. This was confirmed by immunohistochemistry with (species‐specific) anti‐cytokeratin antibodies and by microscopic evaluation of cross‐sections of the porous membrane. This co‐cultivation model appears to be suitable for the in vitro study of the mechanisms of intra‐epithelial expansion of transformed urothelial cell lines.
M‐CSF gene transduction in multidrug‐resistant human cancer cells to enhance anti‐P‐glycoprotein antibody‐dependent macrophage‐mediated cytotoxicity
Authors: Heike Yuji , Sone Saburo , Yano Seiji , Seimiya Hiroyuki , Tsuruo Takashi , Ogura Takeshi
Published: February 2007

A human macrophage‐colony‐stimulating‐factor(M‐CSF) gene inserted into an expression vector (pRc/CMV‐MCSF) was transfected into multidrug‐resistant (MDR) human ovarian cancer cells (AD 10) to induce secretion of human M‐CSF into the medium. The M‐CSF level in the culture medium of the transfected cells reached 100 ng/ml after 7 days, and the ability of the cells to secrete M‐CSF was stable for at least 3 months. Transfection of the M‐CSF gene did not result in any change in expression of MDRI (P‐glycoprotein), proliferation or chemosensitivity of the cells from those of the parent cells. There was also no difference between the transfected and the parent cells in susceptibility to NK cell‐ or interleukin‐2‐activated killer‐cell‐mediated cytotoxicity. Human blood monocytes that had been incubated for 4 days in medium with the culture supernatant of MH‐AD 10 cells exhibited higher ADCC activity than untreated monocytes against MDRI‐positive cancer cells. This effect of the supernatant of AD 10 cells was completely abolished by its treatment with a monoclonal anti‐M‐CSF antibody (MAb). When transfected human MDR cells were injected into nude mice, an inverse correlation was seen between the ability of the cells to produce M‐CSF and their tumorigenicity. Thus, gene modification of MDR cancer cells seems hopeful as a therapeutic method for enhancing anti‐MDRI ‐MAb‐dependent macrophage‐mediated cytotoxicity against human MDR cancer cells.
A role for the fyn oncogene in metastasis of methylcholanthrene‐induced fibrosarcoma a cells
Authors: Takayama Tetsuji , Mogi Yoshihiro , Kogawa Katsuhisa , Yoshizaki Naohito , Muramatsu Hirohito , Koike Kazuhiko , Semba Kentaro , Yamamoto Tadashi , Niitsu Yoshiro
Published: February 2007

Expression of various oncogenes (ras, myc, erbB2, src, fyn, yes and sis) in a high‐metastatic clone (MH‐02) derived from a murine methylcholanthrene‐induced fibrosarcoma A (Meth A) was compared with those of its parent clone (ML‐01) by Northern blot analysis. Two oncogenes, fyn, belonging to the tyrosine‐kinase family, and sis, belonging to the cellular‐growth‐factor family, were found to have higher signals (3.6‐fold and 1.8‐fold respectively) in MH‐02 than in ML‐01 cells. To explore the possibility that higher expression of these oncogenes is involved in enhanced metastasis of the MH‐02 clone, ML‐01 was transfected by a fyn vector and the metastatic potential of the transfectant was examined. Mice administered fyn‐transfected ML‐01 cells had significantly increased metastatic nodules in the lung, as compared with those whose ML‐01 cells were transfected with control vector without the fyn gene. The result indicates that the fyn gene is one of the factors governing the metastatic potential of Meth A cells.
Cancer‐cell traffic in the liver. III. Lethal deformation of B16 melanoma cells in liver sinusoids
Authors: Barbera‐Guillem Emilio , Weiss Leonard
Published: February 2007

It has previously been shown that most of the B16 F10 melanoma cells delivered to the mouse liver via the portal vein are rapidly killed in periportal zone 1 of the sinusoids. Few intact viable cells reach pericentral zone 3 of the sinusoids and of these, only a very small proportion leave the liver to colonize the lungs. The hypothesis has been advanced that one nonexclusive, potential mechanism for cancer‐cell destruction in the liver is a result of the deformation of cancer cells when they enter vessels of smaller diameter than themselves. Where entry is associated with change in shape from spheroid to cylindrical, a mandatory increase in cancer‐cell surface area occurs, which is first apparent and utilizes surface membrane excess (rugosity). If this increase is insufficient, a real increase occurs which, if in excess of approximately 4%, results in lethal surface membrane rupture. This hypothesis predicts that, under these circumstances, cancer‐cell resistance to mechanical trauma is favored by small diameter and utilizable surface membrane excess. To test this hypothesis, the traffic of melanoma cells in the liver following portal‐vein injection has been observed by confocal microscopy and image reconstruction. In accordance with the hypothesis, non‐disrupted cells within the sinusoids have a smaller mean diameter than that of the original inoculum, and show evidence of utilization of surface membrane excess. The results indicate that deformation‐associated trauma, suffered by cancer cells on entry and residence in the microvasculature, may well be an important factor contributing to metastatic inefficiency.
Intravesical administration of indium‐111‐labelled hmfg2 monoclonal antibody in superficial bladder carcinomas
Authors: Bamias A. , Bowles M. J. , Krausz T. , Williams G. , Epenetos A. A.
Published: February 2007

Tumour‐associated HMFG2 monoclonal antibody (MAb) was labelled with indium‐111 and administered intravesically to 20 patients with known or suspected superficial bladder carcinoma. The antibody solution was kept in the bladder for 1 hr and was then washed out. Cystoscopy was performed at 2 and 24 hr after instillation. Radioactivity of tumour and normal tissue obtained from the bladder during cystoscopy and cells recovered from urine after the instillation were counted in a gamma‐counter. Conventional histology, immunocytochemistry and autoradiography were also performed. Mean uptake at 2 and at 24 hr was higher in tumours than in normal samples. Autoradiography showed selective accumulation of radioactivity in cells which expressed the antigen detected by the HMFG2 MAb. There was no correlation of tumour uptake with the grade of tumour. No radioactivity was found in the blood of patients after the instillation. Based on dosimetric calculations, however, the radiation dose that can be delivered to the tumours is not sufficient to be cytotoxic, possibly due to inadequate penetration and retention by tumour tissue. Nevertheless, the significant difference between antibody uptake by the tumours and that by normal urothelium, observed in our study, allow for the possibility of using this approach therapeutically.
Nk‐cell activity in patients with hpv16‐associated anogenital tumors: Defective recognition of hpv16‐harboring keratinocytes and restricted unresponsiveness to immunostimulatory cytokines
Authors: Malejczyk Jacek , Malejczyk Magdalena , Majewski Slawomir , Orth Gerard , Jablonska Stefania
Published: February 2007

Peripheral blood mononuclear cells (PBMC) from patients with active HPV16‐associated pre‐malignant and malignant anogenital lesions display a significantly decreased NK‐cell activity against HPV16‐harboring SKv keratinocytes (NK/SKv) while their cytotoxicity against erythroleukemic K562 cells (NK/K562) remains unaffected. A similar defect can also be seen in some healthy individuals displaying no symptoms of HPV infection (low responders). Analysis with specific Leu I la monoclonal antibodies (MAbs) has revealed that all patients as well as weakly responding control subjects had normal numbers of circulating CD 16+ NK cells. However, PBMC from patients with active disease and weakly responding controls displayed a significantly decreased ability to bind SKv cells. Binding of K562 was in the normal range. In patients in whom the lesions were successfully removed or regressed spontaneously (patients with no lesions), NK/SKv activity did not differ from that of normally responding healthy subjects and the ability of their PBMC to bind SKv cells was unaffected. To determine whether an abrogated NK/SKv cytotoxicity may be corrected by NK‐cell stimulatory cytokines, PBMC were pre‐incubated overnight with IL‐2 and interferon‐α. Both cytokines stimulated NK/K562 activity in all tested groups. Significant stimulation of NK/SKv activity was observed in PBMC from normal and weakly responding controls as well as patients with no lesions. No increase could be seen in patients with active disease. Evaluations of NK‐cell activity before and after surgical removal or spontaneous regression of the lesions showed normalization of primarily depressed NK/SKv activity. Malignant progression was associated with a significant drop in SKv cell killing. Our results suggest that abrogation of NK‐cell activity against HPV16‐harboring targets in patients with HPV16‐associated anogenital neoplasia is associated with restricted inability to recognize the disease‐specific target cells, and may depend on persistence of the lesions.
Loss of heterozygosity on chromosome 13 and its association with delayed growth of retinoblastoma
Authors: Kato Mitsuo V. , Ishizaki Kanji , Ejima Yosuke , Kaneko Akihiro , Tanooka Hiroshi , Sasaki Masao S.
Published: February 2007

Loss of heterozygosity (LOH) on chromosome 13 and the age of patients at operation were studied in 46 cases of retinoblas‐toma (RB) tumors, of which 25 were hereditary and 21 were non‐hereditary. The frequency of LOH was 70% for all informative tumors, but significantly higher in non‐hereditary tumors (90%) than in hereditary ones (52%). Our results suggest that LOH might be involved in the initial somatic events in non‐hereditary tumors. Age at operation of patients with hereditary tumors was significantly lower than that of patients with non‐hereditary tumors. Even when tumors associated with a family history were omitted from among the hereditary cases, the difference was still significant. In the case of hereditary tumors, age at operation of LOH‐negative patients was significantly lower than that of LOH‐positive patients. When tumors associated with a family history were omitted, the difference was still significant. The delay in development of LOH‐positive tumors suggests that LOH for one chromosome 13 may be disadvantageous with respect to growth of RB tumors.
L‐myc Proto‐oncogene alleles and susceptibility to hepatocellular carcinoma
Authors: Taylor Jack A. , Bell Douglas A. , Nagorney David
Published: February 2007

A common inherited RFLP of the L‐myc proto‐oncogene has been reported to correlate with cancer susceptibility or prognosis for some tumors. Using a PCR‐based RFLP assay on DNA extracted from peripheral blood samples, we determined the L‐myc EcoRI genotype of patients with HCC, patients with other liver tumors, and healthy controls. In this polymorphism there are 2 alleles, L and S, which define 3 possible genotypes: LL, LS, and SS. While the genotype distribution of patients with other liver tumors and healthy controls do not differ from one another, both differ significantly from the genotype distribution of patients with HCC. This difference is primarily the result of a low frequency of the SS genotype among HCC patients compared to controls or other liver tumor patients. Persons with the SS genotype appear to be protected against HCC and have roughly one‐ninth the risk of persons who carry one or more copies of the L allele. Within HCC cases, patients with different L‐myc genotypes show slight, but not statistically significant, differences in tumor characteristics and survival.
Expression of the c‐erbB‐3 gene product in gastric cancer
Authors: Sanidas E. E. , Filipe M. I. , Linehan J. , Lemoine N. R. , Gullick W. J. , Rajkumar T. , Levison D. A.
Published: February 2007

The pattern of c‐erbB‐3 gene product was studied in 91 advanced gastric carcinomas, adjacent hyperplastic mucosa, intestinal metaplasia and dysplasia and in normal controls, using immunohistochemistry in archival material. All tumours showed positive c‐erbB‐3 staining in both cytoplasm and membrane. No significant differences of expression were observed between intestinal and diffuse‐type carcinomas or any other clinical parameters. Of interest is the expression in the adjacent mucosa, which is extensive, cytoplasmic, and of lower intensity than in the tumours. Further studies are currently being carried out to clarify the role of this protein in tumour behaviour and gastric carcinogenesis.
Pharmacokinetics and biological responses after treatment of the rat R‐1 rhabdomyosarcoma with methotrexate
Authors: Kipp J. B. A. , Leyva A. , Van Gennip A. H. , Kal H. B.
Published: February 2007

Time relationships of drug concentrations in tissue of a transplantable rat rhabdomyosarcoma and of tumour responses up to 120 hr after treatment with methotrexate (MTX) were analysed and compared. MTX was shown to be retained within the tumour in a substantial concentration for several days, although no evidence of MTX polyglutamation was obtained. The response data confirm that MTX is active in the tumour for up to at least 3 days after injection. Within the first day after MTX treatment the nucleotide pools are only partly depleted. This indicates that the inhibition of DNA synthesis is still incomplete at the time when salvage precursors in increasing amounts are becoming available from decaying cells. From flow cytometric analysis of cell‐cycle progression it is concluded that subsequent cohorts arriving in early S‐phase were retarded, but not inhibited, in their progression through the S phase. At 3 days after MTX treatment the mean rate of cell‐cycle progression as well as the relative clonogenic capacity were maximally reduced to 30% and 1% of control values, respectively. From 3 to 5 days the rate of cell‐cycle progression was gradually restored, whereas from day 5 onwards the clonogenic capacity increased at a high rate corresponding to the proliferation rate of exponentially growing rhabdomyosarcoma cells in culture. However, a continuous reduction of cell recovery lasting for at least 12 days after treatment contributed to an 8‐day delay in tumour volume growth.
Infection with a transforming growth factor α anti‐sense retroviral expression vector reduces the in vitro growth and transformation of a human colon cancer cell line
Authors: Ciardiello Fortunato , Bianco Catcrina , Normanno Nicola , Baldassarre Gustavo , Pepe Stefano , Tortora Giampaolo , Bianco A. Raffaele , Salomon David S.
Published: February 2007

Transforming growth factor α (TGFα) is a growth factor produced by colon cancer cells which may function as an autocrine growth regulator. Therefore, the proliferation and transformation of colon cancer cells might be attenuated by blocking the production of endogenous TGFα. GEO cells, from a human colon carcinoma cell line that expresses TGFα and functional epidermal growth factor (EGF) receptors, were infected with a replication‐defective, recombinant amphotropic retroviral expression vector containing the neomycin‐resistance gene and a 435‐bp Apal‐EcoRI coding fragment of the human TGF α cDNA oriented in the 3′ to 5′ direction under the transcriptional control of the heavy‐metal‐inducible mouse metallothionein 1 promoter. Following antibiotic selection, G418‐resistant colonies were pooled and expanded into a cell line (GEO TGFα AS cells). A 50 to 70% inhibition in the production of secreted and cell‐associated TGFα protein was observed in GEO TGFα AS cells that had been maintained in CdCI2‐supplemented medium. Moreover, a growth inhibition of 70% and 50% was observed in CdCI2‐treated GEO TGFα AS cells under anchorage‐dependent and anchorage‐independent culture conditions, respectively. In contrast, CdCI2 treatment of parental GEO cells had no significant effect upon these parameters. Our results suggest that TGFα may be involved in modulating the in vitro cell growth and transformation of human colon cancer cells that express both this growth factor and its cognate receptor.
Therapy of mouse mammary carcinomas with vincristine and doxorubicin encapsulated in sterically stabilized liposomes
Authors: Vaage Jan , Donovan Dorothy , Mayhew Eric , Uster Paul , Woodle Martin
Published: February 2007

This study tested the therapeutic effects of vincristine sulfate and doxorubicin hydrochloride, each drug in 2 different formulations: (i) as a solution in saline, and (ii) encapsulated in sterically stabilized, long‐circulating liposomes composed of hydroge‐natedsoy‐phosphatidylcholine/cholesterol/polyethylene‐glycer‐ol‐distearoyl‐ phosphatidylethanolamine. The 4 drug preparations were used to treat s.c. implants of the mouse mammary carcinoma MC2. The drugs were given by i.v. injection over 15 to 18 days, starting 3 days after tumor implantation. The single‐drug therapeutic effects of vincristine (S‐VCR) and doxorubicin (Doxil) in liposomes were compared, and the 2 preparations were also tested in alternate and in simultaneous combinations. These new liposome formulations of vincristine and doxorubicin were significantly more effective than the free drugs in curing the mice. Alternate, semi‐weekly injection of both drugs gave the best therapeutic effect. Prolonged circulation time with increased accumulation in tumors are considered likely reasons for the improved therapeutic efficacy of both drugs when encapsulated in these liposomes.
Characterization of four new cell lines derived from small‐cell gastrointestinal carcinoma
Authors: Fujiwara Takato , Motoyama Teiichi , Ishihara Noriko , Watanabe Hidenobu , Kumanishi Toshiro , Kato Kanefusa , Ichinose Hiroshi , Nagatsu Toshiharu
Published: February 2007

Four human small‐cell gastrointestinal carcinoma cell lines were established from tumor tissues of patients with esopha‐geal, gastric or rectal cancer, and were studied morphologically and biochemically in comparison with small‐cell lung carcinoma (SCLC) cell lines and common gastric cancer cell lines. Cells from all the small‐cell gastrointestinal carcinoma lines were as small as classic SCLC cells and had characteristic neurosecre‐tory granules. Cells from only one line grew as tightly packed spherical aggregates of floating cells, and those of the other 3 grew attached to substrate. Although high levels of creatine kinase brain isoenzyme (CK‐BB) were detected in all 4 cell lines, 2 of them showed low levels of aromatic L‐amino‐acid decarbox‐ylase and 3 had low levels of neuron‐specific enolase (NSE). None of the lines showed simultaneous elevation of enzymes. C‐myc, N‐myc, and L‐myc were not amplified in any of the cell lines, but c‐myc mRNA was expressed in 2 lines. Our findings indicate that all small‐cell gastrointestinal carcinoma cells examined belong to the variant type which is used in the classification of SCLC. Furthermore, the ECC18 line, derived from esopha‐geal cancer, seemed to be of true endocrine cell origin, while the 3 other small‐cell gastrointestinal carcinoma lines seemed to arise via neoplastic neometaplasia from adenocarcinoma cells to endocrine cells.
Possible role of activated ras genes in human esophageal carcinogenesis
Authors: Galiana C. , Fusco A. , Martel N. , Nishihira T. , Hirohashi S. , Yamasaki H.
Published: February 2007

Activation by point mutation of the H‐, K‐ and N‐ras genes is found in many tumors. However, no such mutation has yet been found in human esophageal carcinomas from various parts of the world. We have confirmed the absence of mutation at codons 12, 13 and 61 of K‐ and N‐ras and at codons 12 and 61 of H‐ras in 25 primary tumors obtained in France. In contrast, among 7 human esophageal carcinoma cell lines (TE1, TE2, TE3, TE8, TE9, TE TE10, TE 13) with different degrees of tumorigenicity in nude mice, 3 highly tumorigenic lines (TE1, TE2 and TE8) exhibited activation of ras oncogenes; 2 showed a G35 to A35 transition of K‐ras gene and one a H‐ras G35 to T35 transversion. Since these cell lines had been established from tumors of Japanese patients from Sendai, we examined 3 primary esophageal tumors from Tokyo and 19 from Sendai, including the primary tumors from which the TE cell lines had been derived. No ras mutation was detected, which suggests that the ras gene mutations in the TE cell lines are either due to their long‐term culture or that only a small portion of the original tumors contained such mutations. In order to directly examine the effect of ras gene mutation, one of the non‐tumorigenic cell lines, TE 13, was transfected with a plasmid coding for a mutated H‐ras gene (G35 to T35). Transfected clones expressing high levels of mutated ras gene were able to induce tumors in nude mice. Thus, although no primary human esophageal tumor contained mutated ras genes, our studies do not exclude a significant role of mutated ras genes in cell proliferation and malignant transformation of human esophageal cells.
Effect of reactive oxygen intermediates on the in vitro invasive capacity of tumor cells and liver metastasis in mice
Authors: Nonaka Yasuyuki , Iwagaki Hiromi , Kimura Toshikazu , Fuchimoto Sadanori , Orita Kunzo
Published: February 2007

We studied the role of reactive oxygen intermediates (ROls) in experimental liver metastasis induced in mice by the inoculation of COLON 26‐M5 murine colon cancer cells, a highly metastatic variant of COLON 26 cells, and the effect of ROIs on the invasive capacity of the cells in an in vitro chemo‐invasion assay model using reconstituted basement membrane matrigel. We also measured the release of ROIs from cells using electron spin resonance (ESR) spectrometry. Hydroxyl radicals (.OH) were constitutively released from the cells. This release was augmented by pre‐treatment with phorbol 12‐myristate 13‐acetate (PMA). In experimental liver metastasis in CDF1 mice, the administration of recombinant human superoxide dismu‐tase (r‐hSOD) significantly increased the number of metastatic nodules, while administration of catalase significantly inhibited metastasis formation. In vitro pre‐treatment of cells with PMA significantly increased the number of metastatic nodules. Invasive capacity of the cells was markedly augmented by pre‐treatment with PMA. PMA‐induced augmentation was significantly inhibited by the simultaneous addition of r‐hSOD to the assay. Catalase had no significant effect. Our findings suggest that ROIs play an important role in tumor invasion and metastasis, and that hydrogen peroxide (H2O2) may contribute to the retention or extravasation of circulating tumor cells. Furthermore, the superoxide anion (O2 ‐) released by tumor cells may play an important role in basement membrane degradation.
Increased yield in GST‐P‐positive liver pre‐neoplastic foci induced by dena or enu in rats pre‐treated with estradiol or tamoxifen
Authors: Servais P. , Galand P.
Published: February 2007

We investigated the mechanisms by which partial hepatec‐tomy (PH) increases the ability of chemical hepatocarcinogens to induce pre‐neoplastic liver foci. Comparison of the effects of pre‐treatment with PH, estradiol (E2) or tamoxifen (TAM) on the yield in glutathione‐S‐transferase(GST‐P)‐positive pre‐neoplastic foci in rat liver induced by subsequent treatment with ethylnitrosourea (ENU) or diethylnitrosamine (DENA) showed that pre‐treatment with E2 increased the yield in foci induced by subsequent treatment with ENU or DENA, as compared with that in animals not pre‐treated, the increase being of similar magnitude with either carcinogen. Compared with that of PH, the effect of the hormone was much more pronounced than would be expected from the relative mito‐genic effect of the hormonal and surgical pre‐treatments if the mitotic rate were the cause. On the other hand, the average volume of pre‐neoplastic liver lesions in rats treated with ENU or DENA was 2.5 to 5.0 times higher than in rats not pre‐treated whenever PH was included in the pre‐treatment, whereas it was not affected by any other pre‐treatment.
Transplantation of colon carcinoma into granulation tissue induces an invasive morphotype
Authors: Dingemans Koert P. , Zeeman‐Boeschoten Ingrid M. , Keep Robert F. , Das Pranab K.
Published: February 2007

The stroma surrounding many malignant tumors resembles granulation tissue. To test the hypothesis that such stroma stimulates tumor invasiveness, we compared, by electron microscopy and immunohistochemistry, the growth patterns of CC531 rat colon adenocarcinoma in 2 experimental situations: (i) after transplantation into the undisturbed subcutaneous connective tissue of rats, and (ii) after transplantation into experimentally induced subcutaneous granulation tissue in rats. For the latter experimental situation, a subcutaneous „tissue chamber”︁ was designed allowing fragments of tumor tissue to be transplanted into the very center of developing granulation tissue. In the undisturbed subcutaneous tissue, the whole tumor was generally encapsulated, and the tumor cells were arranged in compact groups with a strong tendency to form acini. In the pre‐formed granulation tissue, on the other hand, the tumor tissue closely matched descriptions of invasive colon carcinomas in the literature and met the criteria for the „invasive morphotype”︁. In this situation, the tumor consisted of thin, unorganized, widely dispersed strands of irregular tumor cells with numerous protrusions that deeply penetrated the surrounding matrix. Our results show that an invasive morphotype can be evoked by pre‐inducing granulation tissue at the transplantation site.
Characterization of mouse urothelial cell lines in different phases of transitional‐cell carcinogenesis
Authors: De Boer W. I. , Rebel J. M. J. , Foekens J. A. , Vermey M. , Van Der Kwast T. H.
Published: February 2007

Altered cellular responsiveness to growth factors is one of the factors involved in carcinogenesis. In order to study the role of growth factors in transitional‐cell carcinogenesis, we established 3 urothelial cell lines from normal mouse urothelium, designated g/G, NUC‐5 and NUC‐I. These cell lines were studied by light and transmission electron microscopy, karyotyp‐ing, grafting in syngeneic mice, growth‐factor response in vitro under serum‐free conditions, and EGF receptor expression. In the presence of insulin or insulin‐like growth factors I and II, proliferation of the non‐tumorigenic DNA‐tetraploid g/G and DNA aneuploid NUC‐5 cells is stimulated by EGF, TGFα, bFGF and aFGF. This stimulation can be abolished in g/G but not in NUC‐5 cells by simultaneous addition of TGFβ. Proliferation of g/G and NUC‐5 cells can also be stimulated by PDGF‐AA. The spindle‐cell‐like NUC‐I cells are DNA aneuploid and tumori‐genic in syngeneic mice; they express low levels of EGF receptors and their autonomous proliferation is only affected by insulin or insulin‐like growth factors. Each of these cell lines seems to reflect a different phase in transitional‐cell carcinogenesis: g/G cells have gained immortality, have become tetraploid, but are non‐tumorigenic and growth‐factor‐dependent. NUC‐5 cells have become aneuploid, have a growth‐factor responsiveness different from that of normal epithelial cells, but are still non‐tumorigenic. NUC‐1 cells are aneuploid, tumorigenic, and growth‐factor‐independent. These urothelial cell lines provide a suitable tool for further studies in transitional‐cell carcinogenesis.
Risk of kidney cancer among patients using analgesics and diuretics: A population‐based cohort study
Authors: Lindblad Per , McLaughlin Joseph K. , Mellemgaard Anders , Adami Hans‐Olov
Published: February 2007

The aim of this study was to determine the risk of kidney cancer in 2 cohorts defined on the basis of hospital discharge diagnoses associated with analgesic or diuretic use during the period 1965 to 1983. Patients were followed up through 1984 for cancer incidence. After excluding cancers in the first year of observation, 161 kidney cancers were observed vs. 138 expected among 54,662 patients in the analgesics cohort. The relative risk was higher for women than for men. When examined by sub‐site within the kidney, risk for cancer of the renal pelvis was similar in magnitude to that for the renal parenchyma. Among 115,616 patients in the diuretics cohort, 278 kidney cancers occurred vs. 209 expected. The risk for women was higher than for men. This elevation in risk was confined to cancer of the renal parenchyma, with no significantly increased risk seen for cancer of the renal pelvis. Although we observed little excess risk among members of the analgesics cohort, the significantly elevated risk among patients using diuretics supports a number of recent studies, but inability to adjust for confounding factors such as obesity preclude drawing any conclusion regarding diuretics. Further research is warranted to assess in detail the relationship between diuretic use and cancer of the renal parenchyma. © 1993 Wiley‐Liss, Inc.
Demonstration of a TGF‐α‐EGF‐receptor autocrine loop and c‐myc protein over‐expression in papillary thyroid carcinomas
Authors: Haugen D. R. F. , Akslen L. A. , Varhaug J. E. , Lillehaug J. R.
Published: February 2007

Autocrine growth stimulation has been identified in several types of human cancer. In the present study we wanted to establish whether autocrine stimulation of the epidermal‐growth‐factor receptor (EGF‐r) by its ligand, transforming growth factor alpha (TGF‐α) occurs in thyroid neoplasia. We examined 190 fresh, frozen thyroid tissue samples from 70 patients by immunohistochemistry with antibodies to EGF‐r, TGF‐α, c‐erbB‐2 and c‐myc. EGF‐r expression was detected in 17 out of 19 papillary carcinomas, TGF‐a expression in 10, and c‐erbB‐2 expression in IS. No papillary carcinoma expressed TGF‐a without also expressing EGF‐r. Concomitant expression of EGF‐r, TGF‐α and c‐erbB‐2 was seen in 7 papillary carcinomas. No EGF‐r, TGF‐α or c‐erbB‐2 immunopositivity was found in normal‐appearing thyroid tissue (25 cases), whereas a few of the non‐neoplastic lesions (colloid goitres and diffuse hyperplasias) expressed either EGF‐r or TGF‐α. c‐myc expression was detectable in all tissue samples, and expression was invariably nuclear. Increased expression was observed in 10 out of 19 papillary carcinomas, and 8 of these also co‐expressed EGF‐r and TGF‐α. In situ hybridization confirmed the presence of TGF‐α mRNA in tumour epithelium of TGF‐α‐immunopositive samples. The concomitant expression of EGF‐r, TGF‐α and TGF‐α mRNA gives evidence for a TGF‐α‐EGF‐r autocrine loop in thyroid papillary carcinomas. The increased c‐myc expression may reflect the proliferative advantage of these tumours. © 1993 Wiley‐Liss, Inc.
Cytogenetic findings in 33 osteosarcomas
Authors: Mertens F. , Mandahl N. , Örndal C. , Baldetorp B. , Bauer H. C. F. , Rydholm A. , Wiebe T. , Willén H. , Åkerman M. , Heim S. , Mitelman F.
Published: February 2007

Thirty‐three osteosarcomas (OS) were analyzed cytogenetically. Clonal chromosome changes were detected in 17 cases. Six tumors had chromosome numbers in the diploid range, 6 in the triploid range, 1 in the tetraploid range and 1 in the pentaploid range, while 3 tumors had multiple clones with different ploidy levels. Including the present 17 tumors, a total of 27 OS with clonal aberrations have been reported. The recognizable structural rearrangements in these 27 tumors clustered to chromosome arms 1p, 1q, 3p, 3q, 7q, 11p, 17p and 22q. Chromosome bands 1q11, 1q21, 1q42 and 7q11 were the most frequently rearranged, and the most common numerical rearrangements were ‐3, ‐ 10, ‐ 13 and ‐ 15. Supernumerary ring chromosomes, in 2 tumors as the sole change, were found in all 3 parosteal OS, which is in agreement with the findings in 1 previously reported parosteal OS. The association between ring formation and parosteal morphology represents the first cytogenetic‐morphologic entity among OS. © 1993 Wiley‐Liss, Inc.
p53 protein expression in breast cancer as related to histopathological characteristics and prognosis
Authors: Lipponen P. , Ji H. , Aaltomaa S. , Syrjänen S. , Syrjänen K.
Published: February 2007

Formalin‐fixed, paraffin‐embedded biopsies of 193 women with primary breast cancer followed‐up for over 10 years were analysed immunohistochemically for the expression of p53 protein. Altogether, 58% (113/193) of the tumors were positive for p53 protein. Over‐expression of p53 was associated with the ductal type, high‐grade tumors, dense stromal inflammatory cell infiltrate, high S‐phase fraction, high mitotic frequency and high values of the nuclear factors. In univariate analysis, intense p53 over‐expression predicted a poor outcome, whereas a short recurrence‐free survival (RFS) was related to p53 negativity. In axillary lymph‐node‐negative (ANN) tumors, p53 negativity was related to short RFS, and in axillary lymph‐node‐positive (ANP) tumors this inverse relationship was statistically significant. In Cox's analysis, p53 protein over‐expression had no independent prognostic value comparable with the well‐established prognostic factors. However, p53 protein accumulation was an independent indicator of long RFS in the entire cohort, in ANP tumors and in rapidly proliferating tumors. The results indicate a dual role for p53 protein over‐expression in breast cancer prognosis. The low survival probability associated with intensively p53‐positive tumors is probably related to rapid cancer‐cell proliferation, whereas the long RFS of p53‐positive tumors might be explained by the development of circulating antibodies to p53 protein. The role of p53 protein in breast cancer is incompletely understood, and the p53 gene should be subjected to detailed analysis of specific mutations. © 1993 Wiley‐Liss, Inc.
Cancer among teenagers in Denmark, 1943‐1987
Authors: Martos M. Carmen , Winther Jeanette F. , Olsen Jørgen H.
Published: February 2007

A population‐based study was carried out on 3,988 tumours in teenagers (aged 10‐19 years) diagnosed during the period 1943‐87 in Denmark and abstracted from the files of the National Cancer Registry. In that Registry, codes for tumours were based solely on topography until the end of 1977. In order to obtain a uniform data set, coded by the system of the International Classification of Diseases for Oncology (ICD‐O) now used at the Cancer Registry, all cases of teenage cancer diagnosed prior to 1978 were re‐evaluated, and an ICD‐O code was applied. Tumours were further aggregated into diagnostic groups using an internationally agreed scheme. The average incidence rates for all histological types combined were 136 per million for boys and 108 per million for girls, which are close to those reported in Connecticut, USA. Central nervous system tumours, leukaemia and malignant lymphomas accounted for 60% of all cancers among teenagers. An overall excess of cancers among boys was mainly due to more frequent occurrence of leukaemias, malignant lymphomas, sarcomas and germ‐cell tumours. Increasing trends with time were seen for malignant lymphomas in both boys and girls and for subtypes of non‐seminoma germ‐cell tumour among boys aged 15‐19. For other diagnostic groups, including the main group of leukaemias, the rates have remained largely unchanged, suggesting that environmental factors associated with modern society play a minor role in the aetiology of cancer among teenagers. © 1993 Wiley‐Liss, Inc.
Reduced expression of nm23‐H1, but not of nm23‐H2, is concordant with the frequency of lymph‐node metastasis of human breast cancer
Authors: Tokunaga Yuji , Urano Takeshi , Furukawa Koichi , Kondo Hisayoshi , Kanematsu Takashi , Shiku Hiroshi
Published: February 2007

The nm23 gene is a potential metastasis‐suppressor gene originally identified in a murine melanoma line. Several investigators have reported the probable inverse association of nm23 expression with disease prognosis and/or metastasis. Since there are now 2 known isotypes of human nm23, namely nm23‐H1 and ‐H2, we immunohistochemically examined expression of these isotypes in human breast‐cancer tissues using monoclonal antibodies (MAbs) specific for each isotype protein. We also analyzed expression of c‐erbB‐2 in the same collection of cancer tissues, in order to examine the significance of nm23 expression in comparison with c‐erbB‐2 expression. Of 130 tumors from breast‐cancer patients, 73 (56%) and 69 (53%) positively expressed nm23‐H1 and ‐H2 respectively. Expression of c‐erbB‐2 was positive in 36 (28%). Expression of nm23‐H1, but not nm23‐H2, was inversely associated with lymph‐node metastasis (p < 0.01). Expression of c‐erbB‐2 was associated with Tnm stage, tumor size and lymph‐node metastasis (p < 0.01, p < 0.05 and p < 0.05 respectively). Overall survival was better (p = 0.014) in patients in whom expression of nm23‐H1 was positive than in those in whom it was negative. In multivariate analyses using a Cox's proportional‐hazards regression model with 9 variables, nm23‐H1 showed the fourth greatest contribution to patient survival following lymph‐node metastasis, Tnm stage and menopausal status. No significant contribution was shown for c‐erbB‐2 expression. nm23‐H1, but not nm23‐H2, may perform a role in disease prognosis in addition to its participation in cancer metastasis. It may have value for predicting long‐term survival of human breast‐cancer patients. © 1993 Wiley‐Liss, Inc.
Cytotoxicity, differentiating activity and metabolism of tiazofurin in human neuroblastoma cells
Authors: Pillwein Konrad , Schuchter Katharina , Ressmann Gabi , Gharehbaghi Kamran , Knoflach Andreas , Cermak Benedikt , Jayaram Hiremagalur N. , Szalay Stefan M. , Szekeres Thomas , Chiba Peter
Published: February 2007

The IMP dehydrogenase inhibitor, tiazofurin (TR)‐2‐β‐D‐ribofuranosylthiazole‐4‐carboxamide, which exhibited oncolytic activity in patients with chronic myelogenous leukaemia (CML) in blast crisis was found to inhibit the growth of human neuroblastoma SK‐N‐SH cells with an IC50 of 4.2 μM. TR treatment of cells perturbed nucleic acid and catecholamine pathways. As biochemical markers of TR action decreased cellular GTP pools, increased inosine and hypoxanthine concentrations and depleted dopamine content were found. Incubation of tumour specimens obtained from paediatric patients with grade‐IV neuroblastoma with TR resulted in the formation of the active metabolite, thiazole‐4‐carboxamide adenine dinucleotide, in concentrations sufficient to inhibit tumour growth. Cytotoxic and biochemical effects of TR were enhanced by combining it with allopurinol (an inhibitor of xanthine dehydrogenase), and hypoxanthine (an alternate substrate for hypoxanthine‐guanine phosphoribosyltransferase). Induction of transdifferentiation of SK‐N‐SH cells from a neuroblast to an epitheloid, substrate‐adherent phenotype was more pronounced with TR than with all‐trans‐retinoic acid. Transdifferentiating treatment with TR resulted in a 2‐fold‐enhanced sensitivity towards adriamycin. However, differentiation with all‐trans‐retinoic acid rendered the cells more resistant to adriamycin. Our results suggest that TR might be a promising agent for the treatment of children suffering from neuroblastoma. © 1993 Wiley‐Liss, Inc.