bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of syngeneic anti‐idiotypic antibody on the biodistribution of an anti‐tumour monoclonal antibody in balb/c mice
Authors: Pimm M. V. , Durrant L. G. , Baldwin R. W.
Published: February 2007

BALB/c mice were immunized against syngeneic murine 791T/36 monoclonal antibody (MAb) by intraperitoneal (i.p.) injection of the antibody conjugated to ricin toxin A chain. Subsequently, in these and control mice, the biodistribution of radioiodinated 791T/36 antibody and isotype‐matched (IgG2b) control immunoglobulin was examined. Pre‐treated mice showed marked perturbation of biodistribution of the 791T/36 antibody but not of control IgG2b. This was manifest as rapid hepatic clearance of the antibody which was followed by accelerated catabolism and excretion of the radiolabel. Anti‐idiotypic antibodies were identified in immunotoxin pre‐treated mice by their ability to inhibit the binding of FITC‐labelled 791T/36 antibody to tumour target cells. These studies show that antibody responses, even to only the idiotype of a MAb, may produce marked perturbation of its biodistribution. This has implications for the clinical use of human or chimeric MAbs for tumour imaging or targeting of therapeutic agents since, if anti‐idiotypic antibodies are evoked, they could still prevent tumour localization of antibody or conjugate.
Levels of myc protein, as analyzed by flow cytometry, correlate with cell growth potential in malignant b‐cell lymphomas
Authors: Holte Harald , Stokke Trond , Smeland Erlend , Watt Rosemary , Blomhoff Heidi Kiil , Kaalhus Olav , Ohlsson Rolf
Published: February 2007

We have analyzed c‐myc protein expression during the cell cycle in malignant B‐cell lymphomas by dual flow cytometric detection of a fluoresceinated polyclonal anti‐myc antibody and propidium iodide which binds stochiometrically to DNA. The data obtained were correlated to other parameters of cell activation such as histopathological grading, expression of the activation antigen 4F2, light scatter (proportional to cellular volume), DNA synthesis and percentage of S‐phase cells. The c‐myc protein level was strongly correlated to parameters of DNA synthesis/content. In addition, the oncoprotein level was largely unvarying from the late G1 phase through the rest of the cell cycle in both malignant cells and normal purified B cells stimulated to proliferate in vitro.
Seroprevalence of HTLV‐I in portugal and evidence of double retrovirus infection of a healthy donor
Authors: Cardoso E. A. , Robert‐guroff M. , Franchini G. , Gartner S. , Moura‐Nunes J. F. , Gallo R. C. , Terrinha A. M.
Published: February 2007

The prevalence of antibodies to HTLV‐I in 5,475 Portuguese from 6 regions spanning the country was studied. Overall seroprevalence was 0.55%, indicating that Portugal is not an endemic area for this virus. Seropositives were distributed throughout the country, and no geographic clustering was observed. The seroprevalence of individuals who had lived in former Portuguese colonies in Africa (0.7%) was significantly higher than that of individuals who had not been in Africa (0.36%). An increase in seroprevalence with age was noted, and more females than males were antibody‐positive, though not significantly so. Serum from one donor (1711), originating from Guinea‐Bissau, was shown by Western blot and radioimmune precipitation to react with various proteins of HTLV‐I, HIV‐I and ‐2, and SIV. Based on the serologic profiles and isolation of bona fide HTLV‐I from her lymphocytes (confirmed by immunologic analysis, molecular cloning of the provirus and restriction enzyme analysis and sequencing of the DNA), together with the reactivity of her sera with an HIV‐2 isolate obtained from her husband, we conclude that this donor was doubly infected with HTLV‐I and HIV‐2, rather than being the host to an as yet unidentified retrovirus.
Distribution of fibronectin and laminin in early and advanced signet‐ring‐cell carcinomas of the stomach
Authors: Sugihara H. , Hattori T. , Fujita S. , Fukuda M.
Published: February 2007

An immunoperoxidase method was used to compare the distribution of fibronectin and laminin between superficially spreading and deeply infiltrating parts of signet‐ring‐cell carcinoma of the stomach. In both parts, laminin‐containing basement membranes were generally scarce, but they were observed on some of the cancer cells which had differentiated to glandular cells. Intramucosal invasion fronts of superficially spreading cancers often showed a layered structure, consisting of a middle zone of small cancer cells together with a superficial and a deep zone of signet‐ring cells. In this structure, linear fibronectin and laminin deposits were common on the cancer cells in the deep zone, but rare in the superficial zone. However, fibrillar fibronectin deposits in the stroma were not considerably larger in either zone. At extramucosal invasion fronts of deeply infiltrating (advanced) cancers, a stromal remodelling with an increased amount of fibrillar fibronectin deposits was often observed around the cancer cells, whose cell surface fibronectin was largely lost even from some basement membranes. These findings suggest that invasive activity of signet‐ring‐cell carcinoma may not be related to the mere presence or absence of cell‐surface fibronectin and laminin but to the amount of stromal fibronectin, which could reflect a cell‐stroma interaction. Signet‐ring‐cell carcinomas have a stage of intramucosal growth in which cancer cells may live in dependence upon the pre‐existing stroma and form the layered structure, while in advanced stages cancer cells seemed to have acquired an ability to elicit their own “tumor stroma”.
Reversion of tumorigenicity and decreased agarose clonability after EBV conversion of an igh/myc translocation‐carrying be line
Authors: Torsteinsdóttir Sigurbjörg , Andersson Monika L. , Avila‐Cariño Javier , Ehlin‐Henriksson Barbro , Masucci Maria G. , Klein George , Klein Eva
Published: February 2007

The Epstein‐Barr virus (EBV)‐negative Burkitt lymphoma (BL) line BL‐41, and 5 independently established EBV‐converted sublines, derived by infection with a transforming (B95‐8) or a nontransforming (P3HRI) strain of EBV, were compared for clonability in semi‐solid agarose and for tumorigenicity in immuno‐suppressed mice. One P3HRI viral convertant and 3 out of 4 B95‐8 virus‐converted sublines had a high (>40%) agarose clonability, like the BL 41 parent, and were slightly more tumorigenic than BL‐41. In contrast, the fourth B95‐8 converted subline, BL‐41/95, was virtually non‐tumorigenic and its agarose clonability was much lower (3–23%). It showed a more drastic shift towards an LCL‐like phenotype than the other convertants as reflected by high HLA class‐I and EBV‐encoded latent membrane protein (LMP) expression. BL 41/95 still contains the 8;14 IgH/myc translocation, carried by the parental line, and maintains the same relatively high steady‐state level of c‐myc mRNA and protein as the highly tumorigenic convertants. We conclude that the tumorigenicity of BL41/95 has been suppressed by a gene that acts at a level beyond the expression of the activated oncogene, in the same way as the revertants isolated from ras and SV‐40‐transformed cultures (Klein, 1987b; Bassin and Noda, 1987).
Anti‐tumor and differentiation‐inducing activity of n,n‐dimethylformamide (dmf) in head‐and‐neck cancer xenografts
Authors: Van Dongen Guus A. M. S. , Braakhuis Boudewijn J. M. , Leyva Albert , Hendriks Hans R. , Kipp Bart B. A. , Bagnay Marian , Snow Gordon B.
Published: February 2007

The anti‐tumor activity of the putative differentiation‐inducing agent dimethylformamide (DMF) was assessed in 7 head‐and‐neck xenograft (HNX) lines transplanted into nude mice. The drug was administered intra‐peritoneally at the maximum tolerated dose. A significant growth‐inhibitory effect was observed in 3 out of 7 tumor lines tested. When compared with 5 conventional drugs active in patients with squamous‐cell carcinoma of the head and neck (HNSCC), DMF was as effective as the most active drugs (cisplatin and bleomycin). The most sensitive xenograft line, the poorly differentiated tumor HNX‐14C, was used to test the hypothesis that differentiation induction might play a role in the antitumor activity of DMF. Light microscopic examination did not show clear‐cut alteration of differentiation characteristics such as keratin and keratin pearl formation. Furthermore, we used a monoclonal antibody to study the expression of cytokeratin 10 which is useful as a differentiation marker of human HNSCC tumors. Keratin 10, not present in HNX‐14C tumors grown under control conditions, became expressed in some cells upon DMF treatment. Further evidence for a differentiation‐inducing activity of DMF was found in electron‐microscopic studies. In treated HNX‐14C tumors, in addition to cells with normal ultrastructural features, better‐differentiated cells were observed, as manifested by an increase in the number of tonofilaments and desmosomes. The results show that DMF has a potential value for the treatment of patients with head‐and‐neck cancer, and that differentiation induction might play a role in the anti‐tumor action of the drug.
Suppression of transformation and immortality in human/chinese hamster fibroblast hybrids—a model for suppressor gene isolation
Authors: Wynford‐Thomas D. , Bond J. A. , Paterson H.
Published: February 2007

Somatic cell hybrids were produced by fusion of normal human (foreskin) fibroblasts and a transformed Chinese hamster fibroblast line V79‐8. Overall, approximately 30% of hybrid clones showed stable reversion to normal morphology and growth control in vitro as shown by serum and anchorage dependence. In one‐third of these clones, senescence was observed after a number of generations similar to that required for the human fibroblast parent cells to senesce. The remainder appear to be immortal. Normal human chromosomes can therefore restore growth control with or without finite life‐span to this transformed cell. V79 cells were found to be transfectable at an efficiency compatible with detection of single‐copy gene transfer from genomic DNA. Furthermore, these cells were exceptionally sensitive to negative (“suicide”) selection. Taken together, our data suggest that the V79 line represents an ideal system for isolation of human tumour suppressor genes.
in vitro proliferative responses of spleen lymphocytes from rats bearing progressive or regressive tumors induced by cell variants of a syngeneic colon carcinoma
Authors: Dearden‐Badet Marie‐Théarèse , Pelletier Hélène , Caignard Anne , Martin François
Published: February 2007

From one colonic carcinoma chemically induced in the rat, 2 sublines of tumor cells have been cloned, one (PROb) inducing progressive tumors, the other (REGb) generating tumors that regress a few weeks after s.c. injection into syngeneic hosts. Our study was aimed at comparing cellular immunity between animals bearing PROb or REGb tumors. Spleen cells were first tested for in vitro proliferation in response to mitomycin‐treated PROb or REGb cells. Only spleen cells from rats injected with REGb cells proliferated significantly when mixed with PROb or REGb cells. The proliferative response induced by REGb cells was considerably higher than the response to PROb cells. When spleen cells from rats bearing REGb tumors were cultured with a mixture of REGb and PROb cells at various PROb/REGb cell ratios, PROb cells significantly suppressed the strong proliferative response generated by the same number of REGb cells alone. REGb‐immune spleen cells, after in vitro stimulation by PROb or REGb cells, were not cytotoxic for either cell variant. REGb‐immune spleen cells did not differ in their content of T lymphocytes expressing CD4 or CD8 markers when they were stimulated by PROb or REGb cells in vitro, but REGb cells induced a larger number of activated lymphocytes expressing the IL‐2 receptor. Our results indicate that, compared to REGb cells, PROb cells are poorer stimulators of proliferation of tumor‐immune spleen cells, and that they are able to suppress the proliferative response induced by REGb cells.
Correlative study on neuro‐endocrine differentiation and presence of somatostatin receptors in breast carcinomas
Authors: Papotti M. , Macri L. , Bussolati G. , Reubi J. C.
Published: February 2007

To correlate the expression of neuro‐endocrine (NE) markers with the presence of somatostatin receptors (SSR) in human breast cancer, a series of 100 cases was stained with the Grimelius silver procedure, by immunocytochemistry with specific NE markers (i.e., chromogranin A and B and synaptophysin) and by autoradiography for SSR. Nine cases were positive for at least one NE marker, while 4 cases were positive for all of them. SSR were detected in 17 cases, either with low (10 cases) or with high receptor density (7 cases). A highly significant correlation was established between the expression of NE markers and high SSR density. Our findings are additional evidence of the existence of a group of breast cancers showing morphological and cytochemical similarity with neuro‐endocrine tumors present in other organs. The identification of this type of breast cancer is of biological and potential therapeutic interest.
Pathologic prognostic factors for cutaneous malignant melanoma: The western canada melanoma study
Authors: Worth Ann J. , Gallagher Richard P. , Mark Elwood J. , Yang Paul C. , Lamb Charles , Spinelli John J. , Wood William S. , Threlfall William J. , Hill Gerry B.
Published: February 2007

An analysis of data for histopathologic factors influencing survival was conducted on 798 cases of invasive cutaneous malignant melanoma. On univariate analysis, a number of factors influenced survival; however, when these factors were examined using a proportional‐hazards model, sex and log of depth of penetration were the only factors governing survival. Moreover, these factors were only important in patients with lesions up to 4 mm in depth with no evidence of other disease. For patients with solitary lesions deeper than 4 mm, or patients with regional or distant disease, none of the factors examined in our study was of predictive value for survival assessment.
Increased serum ferritin in chronic liver disease: A risk factor for primary hepatocellular carcinoma
Authors: Hann Hie‐Won L. , Kim Chung Yong , Thomas London W. , Blumberg Baruch S.
Published: February 2007

Previous studies from this laboratory support the view that increased serum ferritin levels are associated with an increased risk of primary hepatocellular carcinoma (PHC). We have tested this hypothesis in a population of Korean patients with chronic liver disease followed for development of PHC. Serum ferritin levels were measured over time in 249 patients with liver diseases (mostly chronic) followed for 2 to 17 years in Seoul, Korea. Most of the patients were chronically infected with hepatitis B virus. During the first 8 months of follow‐up, there were no cases of PHC and no deaths. During this same period, no patient had a serum ferritin level initially below 300 ng/ml and rising above 300 ng/ml, but some patients with ferritin levels above 300 ng/ml experienced decreases to below 300 ng/ml. Therefore, patients were grouped by ferritin level during the first 8 months of follow‐up into 3 categories according to the above criteria. Multivariate analysis showed that consistently elevated ferritin levels (category 3) were significantly associated with the development of PHC. Men were more likely to have elevated ferritin levels than women and were at higher risk of developing PHC. Men who were chronically infected with HBV and had ferritin levels above 300 ng/ml had a 50% chance of developing PHC during the follow‐up period, compared with a 20% risk of PHC for men with lower ferritin levels (categories 1 and 2). This elevated risk of PHC in men with elevated ferritin levels was confined to the first 3 years of follow‐up.
Expression of transforming growth factor alpha messenger rna in the normal and neoplastic gastro‐intestinal tract
Authors: Malden L. T. , Novak U. , Burgess A. W.
Published: February 2007

The presence of TGFα mRNA has been reported previously to occur in primary colon cancers. We report the expression of the normal 4.5 kb TGFα transcript in the mucosa of the normal human gastro‐intestinal tract from oesophagus through to colon. The highest levels of human TGFα mRNA occurred in the duodenum but significant levels were present in all of the mucosa. Similarly, in the rat gastro‐intestinal tract, TGFα transcripts were detected in the lower gastro‐intestinal tract mucosa. The relative abundance of the TGFα mRNA appeared to decrease in distal regions of the gastrointestinal tract. The level of the TGFα mRNA was similar in both the normal and the neoplastic colon tissue. Similarly, in 2 patients with carcinomas, the TGFα mRNA was expressed at similar levels in the tumour and in adjacent mucosa. Although TGFα mRNA is associated with transformed cells from the gastro‐intestinal tract, the presence of this mRNA at equivalent concentrations in normal mucosa suggests that over‐production of TGFα is not an essential feature of carcinomas in the gastro‐intestinal tract.
Sensitivity to genotoxic effects of bleomycin in humans: Possible relationship to environmental carcinogenesis
Authors: Hsu T. C. , Johnston Dennis A. , Cherry Lorraine M. , Ramkissoon Dindyal , Schantz Stimson P. , Jessup John M. , Winn Rodger J. , Shirley Linda , Furlong Cynthia
Published: February 2007

Responses to the genotoxic effect of bleomycin in lymphocytes of blood cultures, expressed as the average number of chromatid breaks per cell (b/c), varied from less than 0.20 to more than 2.00 in 335 normal individuals. More than 11% of the subjects tested showed a b/c rate above 1.00 and more than 22% showed a b/c rate above 0.80. These individuals are considered sensitive to this radiomimetic drug. The distributional profile of bleomycin responses of the control individuals appears to be representative of the normal human population. In patients with cancers of the colon (83), upper aerodigestive tract (head/neck) (77), and lung (71), the frequencies of subjects in the hypersensitive class were found to be between 40 and 50%, and the response profiles were distinctly different from those of the control population. On the other hand, in a group of elderly cigarette smokers, who exhibited no symptoms of lung cancer, the bleomycin sensitivity profile was significantly skewed toward the more resistant stratum, with only one hypersensitive case among 56 individuals tested (1.78%). The sensitivity profile of patients with breast cancer (82) was similar to that of the control population. Our data suggest that: (1) mutagen sensitivity may play an important role in carcinogenesis of organs and tissues that have direct contact with the external environment (respiratory, digestive, and integumentary systems); (2) it appears to have no significant influence on carcinogenesis of tissues that are not directly exposed to the environment (e.g., breast, brain); and (3) it also has little impact on carcinogenesis in individuals with a hereditary predisposition to cancer (e.g., retinoblastoma, Gardner's syndrome). Development of more effective and precise test systems for carcinogen sensitivity is highly desirable for identification of persons at risk.
Histocompatibility antigens in primary and metastatic squamous cell carcinoma of the larynx
Authors: Esteban F. , Concha A. , Huelin C. , Pérez‐ayala M. , Pedrinaci S. , Ruiz‐Cabello F. , Garrido F.
Published: February 2007

A series of 38 primary laryngeal and hypopharyngeal tumours, 15 lymph‐node metastases and normal tissue were evaluated in frozen sections for the expression of MHC class I and II antigens, using monomorphic monoclonal antibodies (MAbs) to HLA‐ABC, β2‐microglobulin, DR, DP, DQ, HLA‐B and polymorphic HLA‐ABC antigens. Normal distant mucosa of larynx reacted to anti‐class I antibodies but not to anti‐class II. In 9 primary tumours (23.7%) HLA class I antigens were not observed. The remaining 29 showed a strong reaction to anti‐HLA‐ABC (heavy chain) and anti‐β2‐microglobulin, although in 3 cases out of 29 no staining was observed with anti‐HLA‐B locus‐specific MAbs. These selective losses were confirmed using the corresponding anti‐HLA polymorphic MAbs. For HLA class II molecules, only DR was observed in 3 of 38 cases. Defective HLA class I expression statistically correlates with high scores according to Jakobsson's criteria for histopathological tumour grading. Loss of HLA‐ABC antigens was most frequent among the cases with poor differentiation (6/8 cases). On the contrary, class II antigen expression was correlated with a well differentiated pattern and a more favourable prognosis (p < 0.001). We have found differences in HLA class I expression when comparing primary tumours and autologous metastases (3/9 cases). Immunoprecipitation and SDS‐PAGE of class I antigens, Northern and Southern blot analyses of MHC class I genes were performed. We have not detected class I gene rearrangement using HLA coding and locus‐specific non‐coding probes. However, we have found a class I transcription defect that corresponds with a class‐I‐negative phenotype.
Effects of propranolol and cimetidine on cysteamine inhibition of gastric carcinogenesis induced in wistar rats by n‐methyl‐n′‐nitro‐n‐nitrosoguanidine
Authors: Tatsuta Masaharu , Iishi Hiroyasu , Baba Miyako , Mikuni T. , Taniguchi Haruo
Published: February 2007

The effects of propranolol and cimetidine on inhibition by cysteamine (2‐aminoethanethiol hydrochloride) of gastric carcinogenesis induced by N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG) and on gastric acid secretion, serum gastrin level, and labelling index of the gastric mucosa were investigated in inbred Wistar rats. Rats received alternate‐day injections of cysteamine (25 mg/kg body weight) with or without propranolol (dl‐propranolol hydrochloride) (2 mg/kg bw) or cimetidine (50 mg/kg bw) in depot form after 25 weeks of oral treatment with MNNG. Prolonged administration of cysteamine significantly reduced the incidence of adenocarcinoma of the glandular stomach. A combination of cysteamine and propranolol significantly accelerated the inhibitory effect of cysteamine on gastric carcinogenesis. However, with concomitant administration of cysteamine and cimetidine, the incidence of adenocarcinoma was slightly but not significantly increased as compared to that after treatment with cysteamine alone. Administration of cysteamine caused a significant increase in gastric acid secretion and serum gastrin level, and a significant decrease in the labelling index of the antral mucosa. A combination of cysteamine and propranolol significantly increased gastric acid secretion by cysteamine alone and significantly decreased the labelling index of the antral mucosa. With this treatment, the serum gastrin level was significantly higher than the basal level, but the stimulated serum gastrin level was significantly lower than observed that after administration of cysteamine alone. In contrast, concomitant administration of cysteamine and cimetidine caused a significant decrease in gastric acid secretion and a significant increase in the serum gastrin level as compared to the levels seen after treatment with cysteamine alone, but had no influence on the labelling index of the antral mucosa. These findings indicate that hypersecretion of acid, but not hypergastrinemia associated with hyposecretion of acid or achlorhydria, exerts a protective effect against gastric carcinogenesis, and that this effect may be related to its activity in decreasing proliferation of the antral mucosa.
Immunodetection of cathepsins b and l present in and secreted from human pre‐malignant and malignant colorectal tumour cell lines
Authors: Maciewicz Rose A. , John Wardale R. , Etherington David J. , Paraskeva Christos
Published: February 2007

Pre‐malignant and malignant human colorectal tumour epithelial cell lines both secreted precursor forms of the 2 cysteine proteinases, cathepsins B and L. The amount of proteinases secreted by these cell lines varied according to the cell density. Comparison at similar cell densities showed that the pre‐malignant, adenoma‐derived cell line (PC/AA) secreted as much, or more, of both cathepsin B and L precursors as did the malignant, carcinoma‐derived cell line (PC/JW/FI). However, mature forms of cathepsins B and L were detected in the culture media of only the carcinoma‐derived cell line, thus indicating that the invasive potential of a tumour may be related to its ability to process extracellularly the secreted precursor enzyme to a mature and consequently active enzyme, rather than to the amount of proteinase synthesized and/or secreted. Similar results were obtained using 2 other epithelium‐derived tumour cell lines, HT/29 (carcinoma) and SP/AN (adenoma). Immunolocation studies showed that cathepsin B was lysosomal while cathepsin L appeared to have a distribution more consistent with a plasma membrane association. Purified human cathepsins B and L (mature form) were capable of solubilizing an isolated basement membrane matrix (bovine anterior lens capsule) In vitro, thus indicating that the secreted mature enzymes and the membraneassociated cathepsin L could potentially degrade basal laminae or sub‐endothelial basement membranes in vivo.
Circumvention of adriamycin resistance by dipyridamole analogues: A structure‐activity relationship study
Authors: Ramu Nili , Ramu Avner
Published: February 2007

Dipyridamole restores sensitivity to Adriamycin (ADR) in drug‐resistant cells. In an effort to elucidate the relationship between activity and chemical structure of dipyridamole, the ability to enhance the growth inhibitory effect of ADR, in multidrug‐resistant (MDR) P388 murine leukemia cells, was determined for 43 derivatives and related compounds. Since both substituted pyrimidopyrimidines and pteridines enhanced the growth‐inhibitory effect of ADR in drug resistant cells, the core skeleton may not be directly involved and rather serve as a carrier for the substituents connected with this activity. The exact positions of the active substituents on the core skeleton did not seem to be critical for exertion of the activity. Activity was dependent on the presence of 3 tertiary amine groups. However, not all tertiary amines showed the same potency which might be related to the degree of basicity and/or the spatial structure of these groups. The most active derivatives carried piperidine and pyrrolidine groups while derivatives with thiomorpholine, 3‐hydroxypiperidine or dimethylamine groups had low activity. Activity was also dependent on the presence of a substituent with partial electronegative charges as found in a diethanolamine group. However, this function could be carried out, with even higher efficiency, by a substituent containing 6π electrons.
Biological activities and cellular uptake studies of fluorescent derivatives of indole alkaloid tumor promoter teleocidin
Authors: Irie Kazuhiro , Okuno Shigenori , Koshimizu Koichi , Tokuda Harukuni , Nishino Hoyoku , Iwashima Akio
Published: February 2007

To investigate the interaction between tumor promoters and their cellular targets, 6 new fluorescent derivatives of indole alkaloid tumor promoter teleocidin were synthesized from (–)‐indolactam V, and examined for induction of Epstein‐Barr virus, binding ability to the TPA receptor on mouse skin and activation of protein kinase C. (–)‐7‐(2‐N‐Dansylaminoethyl)indolactam V (dansyl‐ILV) had strong activities and proved to be a potent tumor promoter in a 2‐stage carcinogenesis experiment. (–)‐2‐Formyl‐7‐decanoylindolactam V (FD‐ILV) showed a weak but significant activity. The other 4 derivatives had little activity. Treatment of HeLa cells with dansyl‐ILV and FD‐ILV resulted in intense fluorescence in the entire cytoplasm and on the nuclear membrane. Inactive or less active derivatives with hydrophobicity similar to that of dansyl‐ILV showed significant cytoplasmic fluorescence, and those far less hydrophobic than dansyl‐ILV or far more hydrophobic than FD‐ILV showed little fluorescence. This suggested that hydrophobicity rather than biological activity determines the cellular uptake of these fluorescent probes.
Effect of erythromycin and tumour necrosis factor on the drug resistance of multidrug‐resistant cells: Reversal of drug resistance by erythromycin
Authors: Hofsli Eva , Nissen‐Meyer Jon
Published: February 2007

WEHI 164 murine fibrosarcoma cells were rendered multidrug‐resistant (MDR) by culture in the presence of actinomycin D. In addition to resistance to actinomycin D, the cells acquired resistance to doxorubicin, mitomycin, vincristine and cycloheximide. The fact that development of resistance to one type of lipophilic chemotherapeutic drug also results in resistance to other structurally unrelated lipophilic drugs suggests that non‐toxic lipophilic agents may interfere with drug resistance by saturating the pathway by which MDR‐cells inhibit drug cytotoxicity. We show that the antibiotic erythromycin significantly reverses the resistance of MDR WEHI 164 cells to doxorubicin and actinomycin D. In addition to crossresistance to chemotherapeutic drugs, 3 out of 4 actinomycin D‐resistant WEHI 164 cell lines also showed higher resistance to tumour necrosis factor (TNF) than the parental WEHI 164 cells. However, whereas verapamil, a calcium antagonist known to reverse multidrug‐resistance, rendered resistant cells more sensitive to chemotherapeutic drugs, it protected the cells from killing by TNF, suggesting that drug resistance and TNF resistance may not be directly connected. A synergistic cytotoxic effect of TNF and actinomycin D was obtained on both the parental and the MDR cells. However, higher concentrations of TNF and actinomycin D were required to obtain a cytotoxic effect in the MDR cells, reflecting actinomycin D and TNF resistance in these cells.
Limiting dilution cloning of B cells from patients with multiple myeloma: Emergence of non‐malignant B‐cell lines
Authors: Clofent G. , Klein B. , Commes T. , Vincent C. , Ghanem N. , Lenoir G. , Lefranc M. P. , Bataille R.
Published: February 2007

Multiple myeloma (MM) is a B‐cell malignancy characterized by the accumulation of slowly proliferating malignant plasma cells in the bone marrow (BM). Several reports have shown the existence of an abnormal B‐cell compartment including proliferative idiotypic B cells (i.e., B cells bearing the same idiotypic determinants as the myeloma protein) in the BM and peripheral blood (PB) of patients with MM. In order to study whether this abnormal compartment can be grownin vitro, we cultured the PB and BM of 23 patients with MM using limiting dilution methods. Our purpose was to restrict the effect of suppressor cells and the possible overgrowth of the cultures by the more rapidly growing B cells, which occurs in bulk cultures. Spontaneously growing cells were obtained only from patients seropositive for the Epstein‐Barr virus (EBV) and all the cultures were composed of B cells carrying the EBV genome. Thus, positive cultures were generated only in the presence of B cells latently infected with EBVin vivo. The mean frequency of these B cells (1 in 25,000 B cells) was as low in MM patients as in healthy donors. This low frequency indicated that malignant cells do not bear the EBV genomein vivoand that thein vivoregulation of the EBV infection is unaffected in patients with MM. No Ig‐gene rearrangements, specific of the autologous myeloma cells, were found in the cell lines obtained from BM or PB. Thus, the putative malignant B cells or myeloma cells were not able to generate cell linesin vitro, either spontaneously or after endogenous infection with EBV.
Natural killer cell immunodeficiency in patients with chronic myelogenous leukemia. III. Defective interleukin‐2 production by t‐helper and natural killer cells
Authors: Chang Weng‐Cheng , Fujimiya Yoshiaki , Casteel Nancy , Pattengale Paul
Published: February 2007

Even though they possess normal to increased numbers of circulating natural killer (NK) cells, patients with chronic myelogenous leukemia (CML) have a functional NK‐cell deficiency which is restorable in vitro in the presence of recombinant IL‐2. We therefore measured the level of IL‐2 production by both T‐helper and NK cells from CML patients as compared to normal controls using PHA‐stimulated peripheral blood mononuclear cells (PBMs) as well as FACS‐sorted CD4+ (OKT4+) lymphoid cells and FACS‐sorted CD16+(B73.1+) lymphoid cells. Peripheral blood mononuclear cells from CML patients demonstrated markedly defective IL‐2 production as compared to normal controls (4.0 ± 1.6 and 5.9 ± 1.4 units/ml after 24 hr of 5 and 10 μg/ml PHA stimulation as compared with 40.7 ± 10.3 and 69.3 ± 15.1 units/ml for normal subjects). In addition to the decreased relative percentage of CD4+ (OKT4+) lymphoid cells in CML patients, FACS‐sorted CD4+ (OKT4+) cells also demonstrated a significant defect in IL‐2 production, (10.8 ± 3.6 units/ml as compared to 39.0 ± 5.8 units/ml after 24 hr stimulation with 10 μg/ml PHA). FACS‐sorted CD16+ (B73.1+) lymphoid cells from CML patients also demonstrated significantly decreased IL‐2 production after 24 hr incubation with increasing concentrations of PHA or with the NK‐sensitive target K562 as compared to normal controls. Defective IL‐2 production by PBMs, CD4+(OKT4+), and CD16+(B73.1+) cells from CML patients was also evident after 48 hr of PHA stimulation. Although the percentages of both T4+2H4+ and T4+4B4+ subsets are significantly decreased in CML patients, CML patients have normal ratios of T4+4B4+/T4+2H4+ subsets as compared to normal controls. These and previous results support the hypothesis that decreased IL‐2 production by both T‐helper and NK cells from CML patients may be mechanistically related to the observed NK‐cell immunodeficiency in CML patients.
Milk drinking, other beverage habits, and lung cancer risk
Authors: Mettlin Curtis
Published: February 2007

The reported beverage habits of 569 lung cancer patients and 569 control patients admitted to Roswell Park Memorial Institute (RPMI) were studied, 355 male cases and 214 female cases being matched to controls within strata of age and residence. Smoking history and an index of vitamin A from vegetables had significant, dose‐response associations with risk. Animal fat intake as measured by an index of animal fats from meats showed elevated risks which were not significant. Three vegetables rich in vitamin A and 3 meats contributing to the animal fat index were, individually, associated with lung cancer risk. Frequency of consumption of milk, coffee, tea, soft drinks and alcoholic beverages was studied in multiple logistic regression analyses which controlled for smoking history, intake of vitamin A from vegetables and education level. Subjects reporting consumption of whole milk 3 or more times daily had a 2‐fold increase in lung cancer risk compared to those who reported never drinking whole milk (RR = 2.14). The same frequency of intake of reduced‐fat milk was associated with a significant protective effect (RR = .54). Significant risk variations were observed for other beverages but, with the exception of frequencies of reported diet cola and decaffeinated coffee intake, dose‐response patterns were not evident.
Chromosomal assignment of woodchuck hepatitis virus (WHV) dna integration sites in a woodchuck hepatocellular carcinoma‐derived cell line (WH257GE10)
Authors: Mizuno Yasutsugu , Murakami Seishi , Matsushita Fumiaki , Unoura Masashi , Kobayashi Ken‐Ichi , Migita Shunsuke , Hattori Nobu , Ohno Sinsuke
Published: February 2007

The chromosomal sites of woodchuck hepatitis virus (WHV) DNA integration were identified in a woodchuck hepatocellular carcinoma‐derived cell line (WH257GE10) by the in situ hybridization technique using 3H‐labelled WHV whole genome (WHV 2) as a probe. The G‐banded chromosome spreads from WH257GE10 were identified and diagrammed schematicaiiy according to their band patterns. WHV DNA was integrated into 2 sites: 33 region of the long arm of chromosome 6 (6q33) and 31 region of the long arm of chromosome 8 (8q31). Chromosomal sites of WHV DNA integration were stable during successive passage periods analyzed in vitro.
Preparation and in vitro cytotoxicity of a methotrexate‐anti‐MM46 monoclonal antibody conjugate via an oligopeptide spacer
Authors: Umemoto Naoji , Kato Yoshinori , Endo Noriaki , Takeda Yumiko , Hara Takeshi
Published: February 2007

A method was developed by which conjugates of methotrexate (MTX) with antibody were prepared via an oligopeptide spacer which, after internalization of the conjugates into the target cells, would be cleaved by lysosomal enzymes to liberate MTX or its derivative(s) for entry of the drug into the cytoplasm through the lysosomal membrane. The conjugate of MTX with a monoclonal antibody (MAb) (aMM46) to mouse mammary carcinoma MM46 cells prepared by this method via Leu‐Ala‐Leu‐Ala showed potent, antibody‐directed cytotoxicity through lysosomal degradation of the conjugate, most likely at the tetrapeptide spacer. This was supported by the following observations: (a) the cytotoxicity of the aMM46 conjugate was more potent than that of the corresponding normal γ‐globulin conjugate, the antibody alone not being cytotoxic; (b) the conjugate retained its potent cytotoxicity to MM46 cells even after removal, by hydroxylamine treatment, of a less stably bound MTX derivative which might have been released extracellularly and have caused non‐specific cytotoxicity by entering the cells via the membrane active transport system for MTX; (c) the cytotoxicity was not inhibited by thiamine pyrophosphate, an inhibitor of the MTX transport system; (d) the cytotoxicity was inhibited significantly with ammonium chloride, which inactivates lysosomal enzymes by raising the pH; and (e) the cleavability of the Leu‐Ala‐Leu‐Ala spacer by the lysosomal enzymes was verified by using bio‐undegradable poly(D‐lysine) and biodegradable poly(L‐lysine) as the lysosomotropic macromolecular carriers: unlike the poly(L‐lysine) counterpart, the direct MTX‐poly(D‐lysine) conjugate showed very weak cytotoxicity while the tetrapeptide‐mediated conjugate of MTX with poly(D‐lysine) exhibited potent cytotoxicity.
Evaluation of the carcinogenicity of different preparations of areca nut in mice
Authors: Rao A. Ramesha , Das Padma
Published: February 2007

Areca nut has been used as a masticatory since antiquity and it is estimated that more than 10% of the world population chews it in a variety of forms. We have evaluated the carcinogenicity of different preparations of areca nut: ripe‐uprocessedsundried nut (R‐UP‐SD), ripe‐processedsundried nut (R‐P‐SD), unripe‐processed‐sundried nut (UR‐P‐SD), ripe‐unprocessed‐sundried‐water‐soaked nut (R‐UP‐SD‐WS) and ripe‐unprocessed‐undried‐water‐soaked nut (R‐UP‐UD‐WS) in mice following diet‐feeding or oral feeding for 12 months. Only unprocessed areca nuts (R‐UP‐SD, R‐UP‐SD‐WS and R‐UP‐UD‐WS), at high doses, displayed a very weak carcinogenicity.
Laminin receptor expression on murine tumor cells: Correlation with sensitivity to natural cell‐mediated cytotoxicity
Authors: Laybourn Katherine A. , Hiserodt John C. , Varani James
Published: February 2007

Previous studies have identified a relationship between the presence of cell surface laminin receptors on murine tumor cells and sensitivity to killing by natural killer (NK) cells. On the basis of these observations, we suggested that laminin and laminin receptors may function to facilitate the interaction of NK‐sensitive murine target cells with NK cells. Our original studies were conducted with a number of genetically unrelated tumor cell lines. In order to extend these earlier observations, studies have now been conducted in which sensitivity to NK‐mediated lysis and responsiveness to laminin were compared in a number of variant populations derived from the NK‐sensitive cell lines Yac‐l and RL‐l and from the NK/ NC‐resistant line P815. All of the lines which interacted with murine NK cells as indicated by sensitivity to killing and/or by ability to “cold‐target” compete with the killing of sensitive Yac‐l cells were able to bind 125l‐laminin and to respond to laminin in an aggregation assay. Of 4 NK‐resistant populations identified in these studies, 3 failed to respond to laminin. These studies indicate that even among genetically related tumor cell lines there is a relationship between laminin receptor expression and interaction with NK cells.
Centchroman—a non‐steroidal anti‐cancer agent for advanced breast cancer: Phase‐II study
Authors: Misra N. C. , Nigam P. K. , Gupta Ruby , Agarwal A. K. , Kamboj V. P.
Published: February 2007

Treatment with Centchroman (3,4‐trans‐2,2‐dimethyl‐3‐phenyl‐4‐p‐(βpyrrolidinoethoxy) phenyl‐7‐methoxy chroman) has been evaluated in 4 male and 75 female patients with advanced breast cancer. The overall response rate, including both male and female cases, was 40.5%. Among the female patients, the overall response rate was 38.7%. The median duration of response was 6 months. One of the 4 male patients showed a complete response and 2 showed partial responses. The responses were more marked for bone, pulmonary, soft tissue, skin and lymph‐node metastases than for liver metastases.
A case‐control study of cancer of endometrium in athens
Authors: Koumantaki Yvonni , Tzonou Anastasia , Koumantakis Eugene , Kaklamani Evangelia , Aravantinos Dionisios , Trichopoulos Dimitrios
Published: February 2007

Eighty‐three women with invasive adenocarcinoma of the endometrium and 164 control women hospitalized for various orthopedic conditions were interviewed regarding demographic, reproductive, socio‐economic and biomedical characteristics, including their use of tobacco, drugs and exogenous estrogens. The data were analyzed by modelling rate ratio (r) through multiple logistic regression. The main results were as follows: women with invasive adenocarcinoma of the endometrium had earlier menarche (r = 0.82 for every additional year; one‐tailed p approx. 0.04), later menopause (r = 1.50 for a 5‐year difference; one‐tailed p approx. 0.004), and fewer live‐born children (r = 0.86 for every additional child; one‐tailed p approx. 0.08); they were also taller (r = 1.33 for a 5‐cm difference; one‐tailed p approx 0.03), whereas weight, adjusted for height, was not a statistically significant risk indicator (one‐tailed p approx. 0.38). Regular use of combination oral contraceptives was associated with a reduced risk of endometrial cancer (r = 0.56), whereas intake of menopausal estrogens for more than 6 months was associated with an increased risk (r = 2.04); however, because of the low frequency of use of exogenous estrogen preparations in Greece, neither of these 2 results was statistically significant. Tobacco smoking was associated with a significantly reduced risk of endometrial cancer; smoking 15–20 cigarettes per day for 20 years was associated with a rate ratio of 0.49 (one‐tailed p approx. 0.03). The protective effect of tobacco smoking was evident only among post‐menopausal women. These results indicate that the risk profile of endometrial cancer is similar in high‐risk and low‐risk countries, and underline the importance of unopposed estrogenic stimulation in the pathogenesis of this cancer.
The use of a monoclonal antibody against a proliferating cell nuclear matrix antigen in the study of solid human tumors
Authors: Yankulov K. Y. , Hadjiolova K. V. , Kounev K. V. , Getov Chr. , Hadjiolov A. A.
Published: February 2007

A monoclonal antibody (MAb) identifies the nuclear antigen p125/6.5 associated with the nuclear matrix and present in proliferating human cells. By direct and indirect immunofluorescence, the presence and distribution of the antigen p125/6.5 in cryostat sections from primary and metastatic solid human tumors has been investigated. The antigen is present in nuclei of malignant and benign tumor cells, but is not detected in adjacent normal tissues. The antigen displays a speckled nucleoplasmic distribution, while nucleoli are negative. The intensity of the immunofluorescence reaction is markedly higher in the nuclei of some individual or grouped tumor cells.
Systemic immunity against a murine colon tumor (CT‐26) produced by immunization with syngeneic cells expressing a transfected viral gene product
Authors: Schackert Hans K. , Itaya Toshiyuki , Schackert Gabriele , Fearon Eric , Vogelstein Bert , Frost Philip
Published: February 2007

We have previously shown that CT‐26 tumor cells expressing the transfected hemagglutination antigen of influenza virus elicit an immune response in syngeneic hosts that is cross‐protective against an s.c. challenge with non‐transfected parental cells. Since CT‐26 is a murine colorectal carcinoma we sought to determine whether the same immuno‐protective effect could be achieved after a challenge with parent tumor cells injected into the usual sites of colon tumor growth and metastasis. We now show that the protection afforded by this immunization protocol is systemic and that animals can be protected against tumor growth in the cecum, lymphatics of the mesentery, liver and lung.
Different class I antigen oligosaccharides on a murine tumor and a lectin‐resistant variant are not responsible for the differential recognition of the tumors by CTL
Authors: Degen Eric , Laferte Suzanne , Elliott Bruce E. , Williams David B.
Published: February 2007

Previous studies have shown that whereas a highly malignant mouse cell line termed MDAY‐D2 (d haplotype) does not elicit a detectable response by cytotoxic T lymphocytes (CTL) in DBA/2 mice, strong anti‐tumor CTL are generated against a wheat‐germ‐agglutinin‐resistant variant, designated MDW3. Additional evidence suggests these anti‐MDW3 CTL may not be a consequence of a unique antigenic determinant on the variant cells. Because MDW3 cells are expected to differ from MDAY‐D2 cells in their surface carbohydrate structures (due to their lectin resistance) and Class 1 major histocompatibility molecules play a crucial role in CTL‐mediated responses, we speculated that the Asn‐linked oligosaccharides present on Class 1 molecules of MDAY‐D2 and MDW3 might be different and could potentially influence recognition by the anti‐MDW3 CTL. High‐resolution gel filtration analyses and Con A‐Sepharose affinity chromatography clearly demonstrated that the oligosaccharides isolated from the H‐2Dd molecule of MDAY‐D2 cells are larger and more highly branched than those of the MDW3 variant. Taken together with the finding that anti‐MDW3 CTL are restricted by H‐2Dd, these results suggested that the larger H‐2DD oligosaccharides on MDAY‐D2 cells could potentially mask or perturb determinants required for recognition by these CTL. To test this postulate, the surface Class I oligosaccharides of both MDAY‐D2 and MDW3 cells were converted to simpler hybrid structures by treatment with the oligosaccharide processing inhibitor, swainsonine. However, no effect was observed on the lysis or binding of either MDAY‐D2 or MDW3 cells by anti‐MDW3 CTL. Thus, the results do not support the possibility that the larger H‐2Dd oligosaccharides on MDAY‐D2 cells are, in themselves, responsible for the poor recognition of the parent tumor by anti‐MDW3 CTL. Our data to indicate, however, that CTL target binding and effector functions are not dependent on the fine structure of complex Asnlinked carbohydrates present on Class 1 molecules and possibly on other, accessory molecules at the target cell surface, since MDW3 cells maintained their sensitivity to lysis by CTL following swainsonine treatment.