bluuebunny/crossref_metadata_2025 huggingface dataset:
Blood coagulation changes in nude mice bearing human colon carcinomas
Authors: Bani M. R. , Falanga A. , Alessio M. G. , Radice E. , Consonni R. , Giavzzi R. , Donati M. B.
Published: February 2007

We studied several blood coagulation parameters and tumor tissue procoagulant activity (PCA) in nude mice bearing human colorectal carcinomas (HCC). In a control group of 51 tumor‐free nude mice, platelet number was 1.2 ± 0.03 ± 106/μl, thrombotest activity 90% ± 2.6 and fibrinogen 172 ± 11 mg/dl. The same parameters were studied in nude mice (n = 71) bearing 7 different HCC lines subcutaneously (s.c.). The results did not significantly differ from those in control mice but there was broad variability among groups of mice injected with different HCC lines, ranging from 0.36 to 2.55 ± 106/μl for platelets, from 100 to 28% for thrombotest activity and from 42 to 460 mg/dl for fibrinogen. The results were significantly (p < 0.05) different from those in the tumor‐free group when each group of HCC‐bearing animals was analyzed individually. A malignant HCC line that grew in the liver of nude mice (n = 24) significantly (p < 0.001) reduced thrombotest activity (58% ± 5.9). The PCA of tissue extracts from tumors grown s.c. in nude mice was assayed. All the HCC xenografts expressed PCA which differed significantly for the various tumor lines (from 25.5 ± 1.9 to 2.8 ± 0.6 unit/mg in tumor tissue). Cancer procoagulant (CP), a cysteine proteinase with a direct factor‐X‐ activating effect, was present in different amounts (84.7 ± 4.3 to 59.5 ± 9.0%) in the tumors. Our results indicates that the nude mouse is a suitable model for evaluating the hemostatic changes induced by human tumors and may represent a tool for investigating the underlying biochemical mechanisms.
Insulin dependence of murine lymphoid T‐cell leukemia
Authors: Pillemer Graciela , Lugasi‐Evgi Hefziba , Scharovsky Graciela , Naor David
Published: February 2007

The in vitro proliferation of the spontaneous lymphoid T‐cell leukemia designated LB was enhanced by physiological, intermediate and supraphysiological concentrations of insulin. The enhancing effect was observed in both serum‐free medium (SFM) and medium containing low concentrations of serum. Guinea‐pig anti‐insulin serum, but not guinea‐pig normal serum, inhibited the proliferation of LB cells incubated either in medium containing serum alone or in medium containing serum and supplemented with insulin. This finding suggests that LB cells use serum insulin as a growth factor. Insulin‐like growth factors I (IGF‐I) and II (IGF‐II) failed to stimulate an appreciable proliferation in LB cells, whereas in the same experiment insulin markedly enhanced the proliferation of this lymphoid leukemia. Furthermore, the concentration of unlabelled insulin required to displace 50% of 125I‐insulin bound to LB cells was 3 orders of magnitude lower than the concentration of IGF‐I required to achieve the same displacement. Our findings indicate that interaction of insulin with its own receptor, and not with IGF‐I receptor, triggers the proliferation of LB cells. Radio‐receptor assays revealed that LB cells express approximately 3,200 molecules of high affinity (Kd = 10−9 M) insulin receptor per cell. None of 7 other tumor cell lines tested responded to insulin. The proliferation of insulin‐stimulated LB cells was also inhibited with tyrphostin, a tyrosine kinase blocker analogous to tyrosine, which perhaps blocks the tyrosine kinase activity of the insulin receptor β‐chain.
Tumor‐antigen‐specific humoral immune response of animals to anti‐idiotypic antibodies and comparative serological analysis of patients with small‐cell lung carcinoma
Authors: Lehmann Hans‐Peter , Zwicky Caroline , Waibel Robert , Stahel Rolf A.
Published: February 2007

We have previously developed 3 monoclonal anti‐idiotypic antibodies (Ab2) of LOU rat origin directed against the binding site of the murine monoclonal IgM LAM8, which recognizes the small‐cell lung carcinoma (SCLC)‐associated sialoglycoprotein antigen sGP90–135. The aim of this study was to compare the efficiencies of these 3 Ab2, designated LY8–229, LX8–531 and LX8–632, to induce antigen‐specific immunity in different animal species without prior exposure of the recipients to the nominal antigen, and thereby possibly select an Ab2 candidate for active immunotherapy against SCLC in patients. The feasibility of this approach was further evaluated by a serological analysis of patients with SCLC compared with healthy individuals, in whom the spontaneous antibody reactivities against SCLC cell lines and Ab2 were tested. LY8–229 was shown to be the most effective Ab2 in inducing antigen‐specific antibodies in BALB/c mice, CBA/J/Zur mice and one NZW rabbit. Furthermore, LY8–229 was the only Ab2 against which significantly elevated idiotype‐specific antibody reactivities existed in sera of patients with SCLC. These reactivities correlated positively with binding to antigen‐positive tumor cells. Our findings suggest that LY8–229 represents in its reactivity pattern the nominal SCLC antigen in humans also, and therefore may be of diagnostic and possibly therapeutic relevance for patients with SCLC.
Tissue vitamin a repletion is impaired by exposure to carcinogen
Authors: Edes Thomas E. , Kwan Sandra M. , Buckley Christopher S. , Thornton William H.
Published: February 2007

Vitamin A appears to exert a protective effect against certain cancers. Epithelial cancers, such as those of the skin, bladder, oropharynx and respiratory tract, have the strongest association with vitamin A. These same cancers are causally associated with exposure to carcinogens such as benzo(α)pyrene (BP), a product of combustion found in cigarette smoke and charbroiled meat. This study was designed to determine whether BP exposure affects tissue vitamin A nutriture. Female Sprague‐Dawley rats were randomized to purified diets, sufficient or deficient in vitamin A, and with or without 200 mg BP/kg feed. Rats were killed after 4 or 6 weeks. Serum, liver and lungs were assessed for vitamin A levels; trachea, stomach, small intestine and bladder were examined for histologic change. Lack of dietary vitamin A resulted in a profound decrease in vitamin A in the serum, liver and lungs (p < .005). No histologic changes were evident in any tissues examined. Serum vitamin A was not affected by dietary BP. In vitamin‐A‐sufficient rats, dietary BP caused a significant decline in hepatic and lung vitamin A. In rats fed vitamin‐A‐deficient diets, dietary BP had no effect on tissue vitamin A. We conclude that chronic exposure to the carcinogen BP leads to tissue depletion of vitamin A, despite a vitamin‐A‐sufficient diet. We postulate that BP impairs tissue repletion by metabolizing incoming vitamin A rather than in situ vitamin A, since BP had no effect on tissue vitamin A levels in rats fed a diet devoid of vitamin A. This BP‐induced vitamin depletion may eventually have a deleterious effect on epithelial tissue health, and may help to explain the association between vitamin A and cigarette‐smoke‐related cancers.
Enhanced induction of colon carcinogenesis by azoxymethane in wistar rats fed a low‐protein diet
Authors: Tatsuta Masaharu , Iishi Hiroyasu , Baba Miyako , Taniguchi Haruo
Published: February 2007

The effects of ad libitum feeding of synthetic, low‐protein diets on the incidence, number and histology of colon tumors induced by azoxymethane (AOM), on the norepinephrine concentration in the colon wall tissue and on the labelling index of colon mucosa were investigated in Wistar rats. Rats received 10 weekly injections of 7.4 mg/kg body weight of AOM and were given synthetic diets of equal calory content containing 25% casein (normal‐protein diet), 10% casein (low‐protein diet) or 5% casein (very‐low‐protein diet). Administration of the low‐ and very‐low‐protein diets resulted in significant increases in the incidence and number of colon tumors at week 30. However, it did not affect the histology of the colon tumors. The low‐ and very‐low‐protein diets also resulted in significant increases in norepinephrine concentration in the proximal and distal portions of the colon wall and in the labelling indices of both parts of the colon mucosa. Our findings indicate that low‐ and very‐low‐protein diets enhance colon carcinogenesis and that this may be related to their effects in increasing the norepinephrine level in the colon wall and in stimulating proliferation of colon epithelial cells.
Comparative biological responses of rabbits infected with human T‐lymphotropic virus type I isolates from patients with lymphoproliferative and neurodegenerative disease
Authors: Lairmore Michael D. , Roberts Beverly , Frank David , Rovnak Joel , Weiser M. Glade , Cockerell Gary L.
Published: February 2007

An experimental rabbit model was used to determine host responses to infection by various human T‐lymphotropic virus type‐I (HTLV‐I) strains. Seven groups of 4 to 5 rabbits each were inoculated with lethally‐irradiated HTLV‐I‐infected cell lines derived from patients with adult T‐cell leukemia/lymphoma or from patients with HTLV‐I‐associated myelopathy. Four separate control groups of 2 rabbits each were inoculated with similarly prepared HTLV‐I‐negative cells derived from rabbits or humans. Anti‐viral antibody responses were assessed by immunoblot assay and hematologic parameters were measured using automated cell counters and cytologic staining. The virologic status of challenged rabbits was determined by co‐culture and HTLV‐I antigen capture assay, as well as by polymerase chain reaction (PCR) amplification of HTLV‐I DNA from peripheral blood mononuclear cells (PBMC) or tissues. The HTLV‐I inocula could be separated into groups based upon their infectivity to rabbits: highly infectious strains elicited intense serologic responses and were detected frequently in tissues by antigen and PCR assays, while other strains were moderately to poorly infectious, induced weak antibody responses and were infrequently detected by antigen and PCR assays. Overall, PBMC appeared to have the greatest quantity of HTLV‐I containing cells, while bone marrow was a poor source of virus. No clinical or hematologic abnormalities were evident during the 24‐week course of infection. Taken together, our results suggest there is heterogeneity in the biological response to HTLV‐I infection which is, in part, dependent on the infecting strain of virus.
Elevated activities of protein kinase C and tyrosine kinase correlate to leukemic cell aggressiveness
Authors: Aflalo Esther , Wolfson Marina , Ofir Rivka , Weinstein Yacob
Published: February 2007

We report a linkage between cell aggressiveness, protein kinase C (PKC) activity, tyrosine kinase (PTK) activity and serum requirement. We used 2 leukemic cell lines induced by Moloney murine leukemia virus (MLV). One line was highly aggressive (BS‐24‐1) and required low serum concentrations (3%) for optimal growth in comparison to the less aggressive line (RO2T) that needed 10% serum for optimal growth. The more malignant cells exhibited higher PKC and PTK activity. This activity was independent of serum concentration between 0.01–10%. In contrast, the weakly malignant cells need a high serum concentration (10%) for optimal PKC or PTK activity. Immunoblot analysis revealed a higher level of PKC protein in the BS‐24‐1 cells than in the RO2T cells. Serum induction of PKC activity did not change the amount of PKC protein in the cytosol or the membrane fractions, indicating post‐translational mechanism regulation of PKC. We suggest that the aggressiveness of BS‐24‐1 resulted from its ability to become independent of growth regulation by serum factors, via autocrine stimulation of PKC and PTK.
Immunization against polyoma tumors with synthetic peptides derived from the sequences of middle‐and large‐T antigens
Authors: Reinholdsson‐Ljunggren Git , Ramqvist Torbjörn , Ährlund‐Richter Lars , Dalianis Tina
Published: February 2007

We have used 9 synthetic peptides corresponding to sequences of polyoma virus small‐T, middle‐T and large‐T antigens as immunogens in order to map antigenic epitopes that can induce polyoma‐tumor‐specific immunity in different mouse strains. We found that immunization of mice with synthetic peptides derived from amino acid (aa) sequences common to all 3 T‐antigens (aa 1–19), or sequences common to only middle‐T and small‐T (aa 162–176), as well as synthetic peptides unique for middle‐T (aa 269–282 and 371–381), or unique for large‐T (aa 108–124, 316–333 and 436–449) can induce immunity against polyoma tumors. The synthetic peptides can be divided into 3 types with regard to immunogenicity; (i) peptides that immunize in more than one mouse strain and may represent immunodominant sites, (ii) peptides that may be immunogenic in only one strain, and thus strain‐specific, and finally (iii) peptides that do not immunize in the strains tested so far.
Tumor‐cell dissociation at the invasion front: A new prognostic parameter in gastric cancer patients
Authors: Gabbert H. E. , Meier S. , Gerharz C. D. , Hommel G.
Published: February 2007

Tumor‐cell dissociation (TCD) is a well‐known feature at the invasion front of malignant tumors, but little attention has so far been paid to its biological significance. Therefore, the aim of the present study was to score the degree of TCD at the invasion front (TCD 0–3) in a retrospective series of 445 gastric cancer patients and to compare its prognostic significance with the parameters T‐stage, tumor size, grade of tumor differentiation, lymph‐node involvement and vascular invasion. We could show that highly significant differences (p < 0.0001, log‐rank test) existed between the 5‐year survival rates of patients with different degrees of TCD (TCD 0:92.3%; TCD 1:62.1 %; TCD 2: 41.2%. TCD 3:38.5%) and that these differences were independent of T‐stage 2, tumor size and grade of tumor differentiation. Univariate Cox regression analysis showed that in intestinaltype carcinomas, T‐stage (Chi‐square: 45.2) followed by blood vessel and lymphatic vessel invasion (Chi‐square: 43.6 and 40.0) had the highest prognostic value, whereas TCD (Chi‐square: 31.5) revealed a prognostic value quite similar to that of lymph‐node involvement (Chi‐square: 35.1). This prognostic relevance was still present in multivariate Cox regression analysis, showing that the determination of TCD provided an increase in prognostic information which significantly (p = 0.026) exceeded the information obtained by the combination of T‐stage and lymph‐node involvement. Our data suggest that TCD is a new prognostic parameter, especially in those gastric carcinomas in which lymph‐node involvement or vascular invasion are not present.
Type‐1 plasminogen activator inhibitor in human breast carcinomas
Authors: Reilly David , Christensen Use , Duch Mogens , Nolan Naimh , Duffy Michael J. , Andreasen Peter A.
Published: February 2007

We have investigated the occurrence of type‐1 inhibitor of plasminogen activators (PAI‐I) in human breast tumors. PAI‐I levels, measured by enzyme‐linked immunosorbent assay, were significantly higher in malignant breast carcinomas (n = 178) than in benign breast tumors (n = 25). The levels of PAI‐I were found to be correlated with those of urokinase‐type plasminogen activator (u‐PA). The presence of PAI‐I in tumor extracts was also demonstrated by immunoblotting analysis. Immunohis‐tochemical investigations by the use of monoclonal and polyclonal antibodies showed that PAI‐I was mostly localized in the tumor islands, associated with the tumor cells; in addition, it was present in vessel walls and in normal duct epithelia, but absent from the stroma. Analysis of RNA extracted from tumors by polymerase chain reaction revealed the presence of PAI‐I mRNA. We conclude that PAI‐I is present in human breast carcinoma cells, and that it is‐at least partially produced locally, either by the cancer cells or by other cells in the tumors. We have previously demonstrated that a high level of u‐PA in human breast carcinomas is associated with poor prognosis. These results, combined with our present findings, present 2 possibilities: either the cancer cells need PAI‐I in order to utilize the u‐PA‐mediated pathway of plasminogen activation for invasion and metastasis; or PAI‐I represents a defense mechanism against tumor invasion.
A case‐control study for evaluating lung‐cancer screening in Japan
Authors: Sobue Tomotaka , Suzuki Takaichiro , Naruke Tsuguo
Published: February 2007

In order to evaluate the efficacy of lung‐cancer screening, a case‐control study was conducted using the data from 50 areas where population‐based lung‐cancer screening programmes have been operated by local municipalities. In most areas, chest X‐ray examinations for all participants and sputum cytology for high‐risk participants were offered annually. Case series consisted of 273 deceased lung‐cancer cases. For each case, 2 to 5 controls (a total of 1, 269 controls) were collected from those who were alive at the time of diagnosis of the corresponding case, matched by sex, age, smoking status and type of health insurance. Cases and controls were limited to a high‐risk group for males and a non‐high‐risk group for females. Screening histories, which were obtained from the list of screenees, were compared between case and matched controls for the identical calendar period before the time of diagnosis of the case. The odds ratio of dying from lung cancer for those screened within 12 months vs. those not screened was 0.72 (95% confidence interval 0.50–1.03; p = 0.07). The odds ratios increased towards unity, as the length of time in which screening histories were compared increased. After adjusting for some other variables, which appeared to be associated with the opportunities of chest X‐ray examination, the estimated odds ratio did not change. These results suggest some benefits from lung‐cancer screening in terms of reduction of lung‐cancer mortality and should be subject to further research.
Spontaneous metastatic potential of rat hepatocarcinoma cells after cell fusion or DNA transfection
Authors: Cassingena Roland , Lafarge‐Frayssinet Christiane , Frayssinet Charles , Nardeux Pierre , Estrade Simone , Viegas‐Pequignot Evani , Dutrillaux Bernard
Published: February 2007

Eight LF × ICIG cell hybrid clones, isolated upon fusion of normal ICIG‐7 human fibroblasts with tumorigenic, non‐metastatic LF CI.2A cells derived from a DAB‐induced rat hepatocarcinoma, were studied. 'They were all highly tumorigenic and were capable of developing spontaneous lung metastases in syngeneic animals. All the hybrids were characterized by a rapid loss of human chromosomes. However, in long‐term culture, they all revealed a persistence of human genetic information as assessed by Southern blotting. In hybrid lines in which human chromosomes were still visible, the most recurrent were numbers 7 and 9. Neither chromosome 7, previously reported to bear some of the genes controlling metastasis in human × mouse T‐cell hybrids, nor chromosome 9 appeared to be correlated with the metastatic potential of LF × ICIG hybrids. The same conclusion applied (I) to a human 3.3‐kb EcoRI DNA fragment which was amplified (approx. 10‐fold) only in metastases induced by one out of 3 metastatic hybrids tested; (2) to the transcription level of c‐Ha‐ras and c‐Ki‐ras genes which was enhanced (approx. 4‐fold) in metastatic and non‐metastatic lines as well. Co‐transfection of LF CI.2A cells with pHSG 272 selectable marker DNA and genomic DNA from normal ICIG‐7 human cells or from a hybrid‐induced metastasis, reproducibly gave rise to geneticin‐resistant transfectants capable of producing spontaneous lung metastases. Neither transfectants nortransfectant‐induced metastases harbored detectable human DNA sequences but all harbored pHSG 272 DNA. These results again call for caution in gene transfer studies of the metastatic process.
Precursor frequency analysis of human cytolytic T lymphocytes directed against autologous melanoma cells
Authors: Coulie Pierre G. , Somville Michel , Lehmann Frédéric , Hainaut Philippe , Brasseur Francis , Devos René , Boon Thierry
Published: February 2007

Limiting numbers of peripheral‐blood mononuclear cells (PBMC) from melanoma patients were stimulated with irradiated autologous tumor cells in the presence of interleukins‐2 and −4 and in the absence of feeder cells. The responder cells were restimulated every week. After 2 to 4 weeks, the micro‐ cultures were tested for their lytic activity against the autologous tumor cells. Significant lysis of the tumor cells was observed with a fraction of these microcultures, whereas no lysis was observed with control microcultures seeded without stimulator melanoma cells. Because our aim was to measure the precursor frequency of CTL showing specificity for the tumor, and not that of NK‐like effectors that were also capable of lysing the melanoma cells, we used cold‐target inhibition with an excess of NK target K562 to inhibit the NK‐like activity. Microcultures whose lysis on the tumor cells was not abolished by K562 competition were observed. The specificity of these CTL clones was confirmed by the absence of lytic activity on autologous T‐cell blasts. The numbers of microcultures with anti‐tumor CTL activity fitted the zero‐order of the Poisson distribution equation, indicating that they resulted from the activity of single T‐cell clones. The frequency of anti‐tumor CTL precursor cells (CTL‐P) of 7 melanoma patients ranged from 1/900 to 1/33,000. Frequencies of anti‐tumoral CTL‐P were higher and NK‐like effectors were less frequent when sorted CDS+ T lymphocytes were used as responder cells.
An immunohistochemical survey of pS2 expression in human epithelial cancers
Authors: Luqmani Yunus A. , Ryall Glenys , Shousha S. , Coombes R. Charles
Published: February 2007

The oestrogen‐inducible pS2 protein isolated from human breast‐cancer cells appears to have prognostic significance in breast‐cancer patients. Using both monoclonal and polyclonal pS2 anti‐sera, we have carried out an immunocytochemical survey of 9 epithelial cancers. Some degree of specific tumour staining was observed in 4 tissues, the extent varying greatly between specimens. Most (11/13) of the colorectal cancers showed immunoreactivity, as did 4/5 pancreatic carcinomas. In some of these cases, patchy staining was also observed in adjacent non‐tumour cells. Two bronchio‐alveolar carcinomas showed positivity, but 5 poorly differentiated adenocarcinomas of the lung did not. In the ovary, staining was observed in 3/3 mucinous cystadenocarcinomas but only in 1 /8 of the serous type. No reactivity was seen in specimens of salivary gland, kidney, liver, prostate or uterus. This pilot study indicates that pS2 may be a useful marker of adenocarcinomas in human neoplasms apart from those in the breast, and suggests that more extensive surveys might be worthwhile.
Attenuating effect of ornithine decarboxylase inhibitor (1,3‐diaminopropane) on bombesin enhancement of gastric carcinogenesis induced by N‐methyl‐N'‐nitro‐N‐ nitrosoguanidine
Authors: Iishi Hiroyasu , Tatsuta Masaharu , Baba Miyako , Okuda Shigeru , Taniguchi Haruo
Published: February 2007

The effects of combined administration of bombesin and the ornithine decarboxylase (ODC) inhibitor 1,3‐diaminopropane (DAP) on the incidence and number of gastric tumors induced by N‐methyl‐N'‐nitro‐N‐nitrosoguanidine (MNNG), the ODC activity of the gastric wall and the labelling index of the gastric mucosa were investigated in inbred Wistar rats. Rats were given drinking water containing MNNG (50 μg/ml) for 25 weeks and then drinking water containing DAP (2.5 g/l) and/or injections of 40 (μg/kg) body weight of bombesin in depot form every other day. Administration of bombesin alone resulted in significant increases in the incidence of gastric cancers, the ODC activity of the antral portion of the gastric wall and the labelling index of the antral mucosa. Administration of DAP with bombesin significantly reduced enhancement by the latter of gastric carcinogenesis, ODC activity of the antral portion of the gastric wall and the labelling index of the antral mucosa. Our results suggest that ODC inhibition attenuated the enhancement of gastric carcinogenesis by bombesin, and that this enhancement by bombesin was mediated by polyamine biosynthesis.
Identification and characterization of a rat protein (P 105) auto‐antigenic in rats bearing a progressive syngeneic colon carcinoma
Authors: Blottière Hervé M. , Menoret Antoine , Burg Cédric , Douillard Jean Yves , Pendu Jacques Le
Published: February 2007

Sera from BDIX rats inoculated with 2 tumor clones derived from a single syngeneic colon carcinoma were assayed by Western blotting for the presence of antibodies against the grafted tumor. The PROb clone is progressive and produces metastases. We observed that rats bearing this tumor developed antibodies against an unglycosylated water‐soluble protein of 105 kDa. The magnitude of this humoral response, as assessed by the intensity of the signal on immunoblots, was inversely correlated with survival of the rats. Furthermore, rats inoculated with the REGb clone, which is immunologically rejected, never developed detectable antibodies against the tumor. Antisera from rats injected with PROb tumor detected p 105 antigen in cellular extracts from the REGb clone and from a series of rat and human cell lines. This protein was also detected in variable amounts in some normal adult and fetal tissues. Treatment of PROb or REGb cells by either interferon‐γ or heat shock did not significantly alter the expression of the p 105 auto‐antigen.
Comparison of spontaneous mutagenesis in early‐passage human mammary cells from normal and malignant tissues
Authors: Eldridge Sandra R. , Gould Michael N.
Published: February 2007

Spontaneous mutant frequencies were determined in early‐ passage epithelial‐cell strains derived from either normal or malignant human breast tissues, as well as a non‐tumorigenic immortalized human mammary epithelial cell line (I84BS) derived from normal cells. Mutations at the hypoxanthine‐ guanine phosphoribosyltransferase (HPRT) locus were quantified by determining the 6‐thioguanine resistance. Mutant frequencies in human mammary epithelial cells (HMEC) from 4 normal and 5 carcinoma tissue samples did not differ significantly. In contrast, the mutant frequency in the immortalized HMEC was approximately 10 times higher than in average normal HMEC and normal non‐immortalized cells from early‐passage cultures of the same cell lineage. Our data suggest that the progression of normal breast cells to invasive carcinoma cells does not necessarily involve the establishment of a general genetic instability during this progression.
Enhanced CMP‐NeuAc:Galβ1, 4GlcNAc‐R α2, 6 sialyltransferase activity of human colon cancer xenografts in athymic nude mice and of xenograft‐derived cell lines
Authors: Olio Fabio Dall' , Malagolini Nadia , Serafini‐Cessi Franca
Published: February 2007

The activity of an α2,6 sialyltransferase acting on N‐acetyllac‐tosaminic sequences (α2,6 ST E.G. 2.4.99.1) has previously been found to be increased in 90% of human colon cancer specimens. In the present study, the α2,6 ST activity of 6 human colon cancer cell lines grown in culture was compared with that expressed by the corresponding nude mice xenografts and by the cell lines derived from the xenografts. We found that xenografts of COLO 205, HT‐29, SW 620, SW 948 and SW 948 FL (a non‐adherent sub‐line of SW 948) cells express an α2,6 ST activity much higher than that of the in vitro‐grown cells. SW 48 cells grown either in culture or as xenografts lack the enzyme activity. All the xenograft‐derived cell lines except HT‐29 retained the increased α2,6 ST activity at least for the first 6 passages. Those derived from SW 948 xenografts showed an enrichment of round, non‐adherent cells, strongly reactive with the NeuAcα2,6Gal/GalNAc‐specific lectin from Sambucus nigra (SNA), thus indicating that a selection of these cells has occurred.
Sister chromatid exchanges and chromosome aberrations in lymphocytes of nurses handling antineoplastic drugs
Authors: Goloni‐Bertollo Eny Maria , Tajara Eloiza Helena , Manzato Antonio José , Varella‐Garcia Marileila
Published: February 2007

Chromosomal aberrations (CA) and sister‐chromatid exchanges (SCE) were investigated in peripheral lymphocytes of 15 nurses and nurse's aides handling cytostatic agents in hospital oncology units. Significantly increased frequencies were noted for both CA and SCE rates when the exposed individuals were compared with 15 nurses working in other hospital units and to a control sample matched by sex and age. This points to the need for emphasizing protective measures in the handling of anti‐neoplastic agents.
Plasminogen activator system in human breast cancer
Authors: Sumiyoshi K. , Serizawa K. , Urano T. , Takada Y. , Takada A. , Baba S.
Published: February 2007

We measured antigen levels of 2 kinds of plasminogen activator, tissue‐type plasminogen activator (t‐PA) and uroki‐ nase‐type plasminogen activator (UK), as well as those of their primary inhibitors, type‐1 plasminogen activator inhibitor (PAI‐I) and type‐2 plasminogen activator inhibitor (PAI‐2), in tissue extracts from benign and malignant breast tumors. Tumor tissue samples from 40 fibroadenomas and 40 breast cancers were examined. t‐PA antigen levels were the same in the 2 groups. Malignant tumors contained higher levels of UK antigen than did benign tumors. In the case of breast cancer, UK antigen levels of tumors with axillary lymph‐node involvement were significantly higher than those of tumors without lymph‐ node involvement. PAI‐1 and PAI‐2 antigen levels of breast‐ cancer tissue samples were higher than those of fibroadenoma samples. PAI‐1 antigen levels of carcinomas with lymph‐node involvement were also significantly higher than those of carcinomas without node involvement. PAI‐2 antigen levels, on the contrary, were higher in carcinomas without node involvement. UK, PAI‐1 and PAI‐2 antigen levels are potentially excellent independent factors for prediction of the metastatic potential of breast cancers.
Detection of antibodies to a linear epitope on the major coat protein (L1) of human papillomavirus type‐16 (HPV‐16) in sera from patients with cervical intraepithelial neoplasia and children
Authors: Cason John , Kambo Parminder K. , Best Jennifer M. , McCance Dennis J.
Published: February 2007

Antibodies to the major (L1) coat protein of human papilloma‐ virus type 16 (HPV‐16) in sera from patients with cervical intra‐epithelial neoplasia (CIN) have been investigated by means of recombinant proteins and synthetic peptides. When L1‐ HPV‐16 fusion proteins were used in immunoblot assays, no antibody reactivity was found in sera from 52 patients with CIN or from 21 unrelated children. Amino‐acid sequence analyses indicated that L1‐HPV‐16 amino acids 473 to 492 may contain an HPV‐16 type‐restricted epitope since the greatest diversity occurs in this region. In the ELISA, seropositivity to peptides 473 to 492 was more common among CIN patients whose biopsies contained HPV‐16 DNA (91%, 21 of 23) than among their children (24%, 5 of 21; p < 0.001) or other CIN patients with HPV‐16 DNA‐negative biopsies (66%, 19 of 29; p < 0.05), but was unrelated to the severity of the CIN lesion. Antibodies to L1‐HPV‐16 peptide 473 to 492 among seropositive CIN patients cross‐reacted with the analagous L1‐HPV‐33, but not with the L1‐HPV‐6b peptide, and were predominantly IgM. In contrast, antibodies which recognized a less variable region of L1 ‐HPV‐16 (amino acids 279 to 293) showed no association with HPV‐16 DNA status. Seropositivity to the L1‐HPV‐6b (amino acids 473–492) was less frequent (33%) among CIN patients and unassociated with HPV‐16 DNA status (p > 0.1); however 51% (37 of 72) of patients with genital warts had antibodies to this peptide.
Expression and splicing patterns of human papillomavirus type‐16 mrnas in pre‐cancerous lesions and carcinomas of the cervix, in human keratinocytes immortalized by HPV 16, and in cell lines established from cervical cancers
Authors: Sherman L. , Alloul N. , Golan I. , Durst M. , Baram A.
Published: February 2007

We have analysed the splicing patterns of human papillomavirus (HPV) type‐16 mRNAs in a human epithelial cell line immortalized by HPV 16 (HPKII), in cell lines established from cervical carcinomas (SiHa and CaSki) and in pre‐invasive and invasive carcinomas of the cervix. The presence of mRNA species previously described, which could encode the E6, E6I, E6II, E6III, E7, E2, E2C, E4, E5 and L1 proteins, was determined, using the RNA polymerase chain reaction (PCR) technique with primers that flank unique splice sites. The state of the viral DNA in the tumor biopsies was established by Southern blot analysis. The various HPV 16 transcripts could be detected in cell lines and in tumor biopsies. The size of the RNA PCR products were in agreement with the previously mapped splice sites. The full range of transcripts was revealed in the HPKII cell line and in a number of pre‐invasive carcinomas. Messenger RNAs which could encode the E6III, E4 and E5 proteins were most prevalent in all types of tumor. The overall results of DNA and RNA analyses in cell lines and tumor specimens indicate that (1) expression of either of the early or late transcripts studied is not specifically related to (a) tumor stage or (b) the physical state of the viral genome; and (2) alterations in the splicing patterns of HPV 16 transcripts may not be involved in tumor progression.
Association between childhood rhabdomyosarcoma and maternal history of stillbirths
Authors: Ghali Mohammad H. , Yoo Keun‐Young , Flannery John T. , Dubrow Robert
Published: February 2007

A case/control study of childhood rhabdomyosarcoma (RMS) was conducted utilizing information from birth records. Cases among Connecticut residents age 19 and younger diagnosed between 1960 and 1988 were identified from the Connecticut Tumor Registry files. Connecticut birth certificates were located for 103 of the 130 cases identified. A random sample of control birth certificates was frequency‐matched to the cases by year of birth, sex, and ethnic origin, with a control:case ratio of 2:1. Information abstracted from birth certificates included birth weight, length of pregnancy, plurality, birth order, mother's prior stillbirths, mother's age, father's age, and father's occupation. Data were analyzed by conditional logistic regression. The major finding was an association between RMS and the mother having had one prior stillbirth or more (odds ratio = 3.7; 95% confidence interval = 1.5 to 8.9). Particularly noteworthy was the observation that 6 mothers of cases, but no mothers of controls, had had 2 or more prior stillbirths. The trend for increasing risk of RMS with increasing number of mother's prior stillbirths was highly significant (p = 0.0004). This association suggests that RMS and a class of stillbirths share a common etiologic factor. This factor may be genetic or may involve in utero exposure to an exogenous or endogenous agent.
Smoking and colorectal cancer risk: Data from the Melbourne colorectal cancer study and brief review of literature
Authors: Kune Gabriel A. , Kune Susan , Vitetta Luis , Watson Lyndsey F.
Published: February 2007

Lifetime smoking data were obtained from 715 colorectal cancer cases and 727 age/sex matched community controls as one part of a large, comprehensive, population‐based study of colorectal cancer aetiology and survival in Melbourne, Australia, The Melbourne Colorectal Cancer Study. Statistically significant associations were found for those males smoking hand‐ rolled cigarettes and for cigar‐/pipe‐smoking males with colon cancer. Review of 18 previous case control studies of colorectal cancer showed an elevated risk for cigar‐smoking black males in one study, a statistically non‐significant increased risk for current smokers in one of 3 cohort studies and a statistically significant elevation of risk for smokers in 2 of 3 studies of adenomatous large‐bowel polyps. Although at present there is insufficient evidence to link smoking with large‐bowel cancer, the possibility that ingested tobacco is in some way carcinogenic for the colorectal mucosa may be worth further study.
Immunological analysis of 17β‐hydroxysteroid dehydrogenase in benign and malignant human breast tissue
Authors: Poutanen M. , Isomaa V. , Lehto V.‐P. , Vihko R.
Published: February 2007

The expression of 17β‐hydroxysteroid dehydrogenase (17‐ HSD) enzyme protein was studied in benign and malignant human breast tissue using the time‐resolved immunofluorometric assay (IFMA), immunoblotting and immunohistochemistry. The presence and distribution of estrogen and progestin receptors was also analyzed immunohistochemically. Cytosolic 17‐HSD concentrations in malignant breast specimens were highly variable (⩽ 0.2–311 ng/mg protein). As was previously found for the placental enzyme, the molecular weight of the 17‐HSD expressed in malignant breast tissue was 35 kDa, estimated following polyacrylamide gel electrophoresis and immunoblotting. The cellular distribution of 17‐HSD was further studied by immunohistochemistry. Immunostaining for 17‐HSD was observed in 71% of the benign breast lesions (fibroadenomas and cases of mastopathia chronica) and in 47% of the cancer specimens (intra‐ductal carcinomas, invasive ductal carcinomas). In benign lesions, the staining was exclusively localized in the cytoplasm of epithelial cells, with no immunoreactivity in the stromal cells. The staining in the cancer specimens was also detected only in the cytoplasm of malignant epithelial cells. A strong or moderate expression of 17‐HSD was related to the presence of PR in the specimen (x2 ‐ 4.657, p = 0.031). However, the expression of PR was not a prerequisite for expression of 17‐HSD in all the cancer specimens. Our data suggest that, in addition to the reported regulation of 17‐HSD by progestins, other factors are also involved in this process in breast tissue.
Clinical and biological significance of HSP89 alpha in human breast cancer
Authors: Jameel A. , Skilton R. A. , Campbell T. A. , Chander S. K. , Coombes R. C. , Luqmani Y. A.
Published: February 2007

In order to isolate and characterize genes whose expression may be altered in breast malignancy, we screened a cDNA library with a polyclonal anti‐serum against breast‐cancer‐ metastasis membranes and isolated several immunopositive clones. One of these, AJ I, was analyzed in detail and found to be expressed at varying levels as a 3.3‐kb mRNA in all of 143 breast cancers. High expression was associated with lymph‐node involvement (p = 0.03). Comparison between high‐ and low‐ expressing groups showed a significant difference at 4 and 6 years for both overall (p = 0.004 and p = 0.002 respectively) and disease‐free (p = 0.0001 and p = 0.04 respectively) survival, but not at 11 years. AJ I was expressed at much lower levels in non‐malignant biopsies as compared with malignant tissue (p = 0.001). Expression was observed in breast‐cancer cell lines MCF‐7, ZR‐75‐1, T47D, MDA‐MB‐231 and HBL 100. Partial sequence analysis of the 620 bp clone showed complete homology with human heat‐shock protein 89 alpha. In addition to being heat‐inducible in all the breast cell lines examined, AJ I levels were increased by estradiol (blocked by cyclohexamide and tamoxifen), EGF, oxytocin and vasopressin in a time‐ dependent manner in MCF‐7 cells and by estradiol, EGF, prolactin and hydrocortisone in T47D cells. In MDA‐MB‐231 cells, EGF caused down‐regulation of AJ I mRNA levels. The increasing evidence for the association of heat‐shock proteins with steroid receptors suggests that Aj I may play an important role in the control of estrogen‐receptor transcriptional activity in breast cancers.
Different behaviour of mouse‐human chimeric antibody F(ab')2 fragments of IgG1, IgG2 and IgG4 sub‐class in vivo
Authors: Buchegger Franz , Pèlegrin Andre , Hardman Norman , Heusser Christoph , Lukas John , Dolci Wanda , Mach Jean‐Pierre
Published: February 2007

Mouse‐human chimeric monoclonal antibodies (MAbs) of 3 different human IgG sub‐classes directed against carcinoembryonic antigen (CEA) have been produced in SP‐0 cells trans‐ fected with genomic chimeric DNA. F(ab')2 fragments were obtained by pepsin digestion of the purified chimeric MAbs of human IgG1, IgG2 and IgG4 sub‐class and of parental mouse MAb IgG. The 4 F(ab')2 fragments exhibit similar molecular weight by SDS‐PAGE. They were labelled with 125I or 131I and high binding (80 to 87%) to purified unsolubilized CEA was observed. In vivo, double labelling experiments indicate that the longest biological half‐life and the highest tumour‐localization capacity is obtained with F(ab')2 from chimeric MAb of human IgG2 sub‐class, whereas F(ab')2 from chimeric MAb IgG4 give very low values for these 2 parameters. F(ab')2 from chimeric MAb IgG1 and from parental mouse MAb yield intermediate results in vivo. Our findings should help to select the appropriate human IgG sub‐class to produce chimeric or reshaped MAb F(ab')2 to be used for tumour detection by immunoscintigraphy and for radioimmunotherapy.
Regulation of natural antibody binding and susceptibility to natural killer cells through Zn++‐inducible ras oncogene expression
Authors: Tough David F. , Haliotis Tina , Chow Donna A.
Published: February 2007

Changes in the natural resistance phenotype were examined for the 2H1, 10T½ cells expressing the activated human H‐ros oncogene under the transcriptional regulation of the zinc‐ inducible mouse metallothionein‐1 promoter. Culture of the cells in 50 μM ZnSO4 induced an increase in ras protein p21 levels which were maximal within I day. Natural‐antibody (NAb) binding was significantly increased following 2 days of cell culture in ZnSO4 and continued to increase up to 4 days. The increased NAb binding returned to uninduced levels within 2 days following the removal of added zinc ions from the culture medium. The cells also exhibited a significant increase in natural killer (NK) cell sensitivity following 2 days in ZnSO4. This was maintained as long as the zinc was in the medium, but returned to uninduced levels within I day following its removal. The results show that NAb binding and susceptibility to NK cells increased following ras oncogene expression in 10T½ cells and that both parameters were regulated by p21 expression. Repeated i.v. administration of whole‐serum NAb prior to tumor inoculation reduced the number of early tumors following s.c. injection of Zn++‐induced 2HI cells into Zn++‐treated C3H/ HeN mice, consistent with an in vivo role for NAb in the defense against ras‐transformed cells. In contrast, small but statistically significant reductions in NAb binding were observed following v‐H‐ras transformation of NIH 3T3 cells or v‐src transformation of 10T½. The data argue for an NAb‐ and NK‐cell‐susceptible phase of ras‐induced tumor development which is a prerequisite for these mediators to contribute to a first line of defense against incipient neoplasia, and suggest that characteristics of the recipient cell and the transforming oncogene are important in determining the natural resistance phenotype.
Interleukin‐1 production by transformed fibroblasts. II. Influence on antigen presentation and T‐cell‐mediated anti‐tumor response
Authors: Zöller Margot , Douvdevani Amos , Segal Shraga , Apte Ron N.
Published: February 2007

Oncogene‐transformed fibroblasts which expressed IL‐1, spontaneously or after activation with conditioned medium (CM) and lipopolysaccharide (LPS), regressed in the syngeneic host. Since regression was significantly influenced by the immune competence of the host (see companion report), we speculated that regression was T‐cell‐mediated. Frequencies of cytotoxic T‐cell precursors (CTLp) were in the same range for activated and non‐activated, transformed fibroblasts. Furthermore, it was found that lysability of transformed fibroblasts was not influenced by expression of IL‐1. These findings exclude the possibility that regression of CM‐ and LPS‐treated transformed fibroblasts may have been due to the appearance of new, strongly immunogenic epitopes. On the other hand, frequencies of CTL were significantly increased after in vivo immunization with IL‐1‐expressing as compared to IL‐1‐non‐expressing transformed fibroblasts. The in vivo maturation/expansion of CTL could have been the consequence of activation of helper T cells (TH), transformed fibroblast‐associated IL‐1 delivering the co‐ stimulatory signal. Analysis of frequencies and proliferation rates of TH confirmed this assumption. Both parameters were significantly increased after stimulation with transformed fibroblasts expressing IL‐1, in comparison to transformed fibroblasts not expressing IL‐1. Furthermore, purified T cells apparently depleted of cells expressing MHC class‐II antigens, i.e. antigen‐ presenting cells, proliferated in the presence of transformed fibroblasts expressing IL‐1. Since IL‐1 rather than MHC class‐II antigen expression was the limiting factor, antigen presentation by IL‐1‐expressing transformed fibroblasts appears unlikely. Instead, maturation of antigen‐presenting cells could well have been initiated by tumor‐associated IL‐1. We conclude that IL‐1 expression of transformed fibroblasts plays an important role in the induction of a T‐cell‐mediated anti‐tumor response. The effect is due to increased efficiency in the activation of helper T cells and may be supported by activation of antigen‐presenting cells.
Induction of synthesis of manganous superoxide dismutase in L‐M(pNtnF) cells carrying an inducible TNF gene
Authors: Himeno Takeshi , Watanabe Naoki , Yamauchi Naofumi , Maeda Masahiro , Okamoto Tetsuro , Tsuji Naoki , Tsuji Yasushi , Akiyama Shinichiro , Sasaki Hiroyoshi , Niitsu Yoshiro
Published: February 2007

Based on findings that the cytotoxic effects of tumor necrosis factor (TNF) are closely related to levels of intracellular oxygen radicals, and on the results of TNF gene transfection studies, the hypothesis was made that endogenous TNF (enTNF) acts as a protective factor against exogenous TNF by inducing inhibitors or scavengers of oxygen radicals. In order to test this hypothesis, we investigated the intracellular levels of manganous superoxide dismutase (MnSOD) and glutathione (GSH) in L‐M(pNTnF) cells carrying a TNF gene induced by dexametha‐ sone (DM). When L‐M(pNTnF) cells were treated with DM they expressed enTNF, and acquired resistance to exogenous TNF. There was no change in the GSH concentration after enTNF induction, but a 1.9‐ to 3.9‐fold increase in MnSOD levels was noted. Our findings suggest that enTNF exerts its protective function against the cytocidal effect of exogenous TNF by inducing MnSOD production.
Influence of dose and schedule on the therapeutic efficacy of 131I‐labelled monoclonal antibody 139H2 in a human ovarian cancer xenograft model
Authors: Molthoff Carla P. M. , Pinedo Herbert M. , Schlüper Hennie M. M. , Boven Epie
Published: February 2007

The therapeutic efficacy of various doses and schedules of 131I‐labelled anti‐episialin monoclonal antibody (MAb) 139H2 was assessed in the NIH:OVCAR‐3 human ovarian cancer xenograft model. Radioimmunotherapy was started at the time s.c. tumors were well established (100 to 300 mm3). The anti‐tumor effects induced by i.v. injections of 131I‐MAb 139H2 were dose‐ and schedule‐dependent. Optimal growth inhibition and long‐lasting complete tumor regressions were obtained with 2 injections of 500, 700 or 750 μCi 131I‐MAb 139H2 per mouse given with a 2‐week interval. The percentage of tumors with more than 50% reduction of their initial volume after treatment with a total dose of 1,000 μCi 131I‐MAb 139H2 per mouse, given as 10 injections of 100 μCi (3 ± /week), 4 injections of 250 μCi (2 × /week), 10 injections of 100 μCi (5 ×/week) within a period of 3 weeks, or 2 injections of 500 μCi with a 2‐week interval, was 9%, 40%, 64% and 75% respectively. Unlabelled MAb 139H2 did not affect tumor growth, while the effects of 131I‐control MAb were minor and transient. 131I‐MAb 139H2 treatment did not select for outgrowth of episialin‐ negative cells in the OVCAR‐3 xenografts. Highest absorbed doses of whole‐body‐radiation were calculated for 2 injections (500 to 750 μCi 131I‐MAb 139H2) given with the 2‐week interval. The radiation dose to, the tumor after a single injection of 500 μCi 131I‐MAb 139H2 was 1,300 cGy over 7 days, which appeared slightly lower than the dose calculated after administration of a tracer dose of iodinated MAb 139H2.