bluuebunny/crossref_metadata_2025 huggingface dataset:
Reverse‐zymographic analysis of protease nexin‐II/amyloid β protein precursor of human carcinoma cell lines, with special reference to the grade of differentiation and metastatic phenotype
Authors: Kataoka Hiroaki , Seguchi Kohji , Iwamura Takeshi , Moriyama Takuzou , Nabeshima Kazuki , Koono Masashi
Published: February 2007

Trypsin inhibitors in serum‐free conditioned media (SFCM) of various human carcinoma cell lines were analyzed by reverse zymography. Most of the cells secreted high‐molecular‐weight trypsin inhibitors (HMTI) larger than 100 kDa. The cell lines of colorectal carcinoma origin had a tendency to secrete HMTI whose molecular weight was a little higher than that of the other cell lines. Analysis of SFCM of subclones with different histological differentiation and metastatic/invasive potentials derived from a single pancreatic carcinoma cell line SUIT‐2 showed that the HMTI activity in SFCM was correlated to the degree of histological differentiation in vivo and tended to be inversely correlated to their metastatic/invasive capabilities. Immunoblotting analysis revealed that these HMTI were protease nexin‐ll/amyloid β protein precursors (PN‐II/APP). Semi‐quantificative reverse‐transcriptase/polymerase‐chain reaction study for PN‐II/APP mRNAs suggested that the differences in PN‐II/APP activities in SFCM between the subclones might be post‐transcriptional or post‐secretional events. In addition, SFCM of a highly metastatic subclone contained 43‐kDa protein which reacted to anti‐APP monoclonal antibody (MAb) suggesting that the subclone may have APP‐degrading activity. © 1995 Wiley‐Liss, Inc.
Inhibition of aberrant crypt growth by non‐steroidal anti‐inflammatory agents and differentiation agents in the rat colon
Authors: Wargovich Michael J. , Chen Chi Dai , Harris Charles , Yang Eileen , Velasco Marco
Published: February 2007

Aberrant crypts are aggregates of single to multiple colonic crypts evidencing hallmarks of dysplasia and may be the earliest detectable pathological lesions for colon cancer. The aberrant crypt assay has been developed in 2 protocols. In one, putative chemoprevention agents are tested for inhibitory effects when administered concomitantly with a carcinogen. In the other, the objective of this study, aberrant crypts were induced in F344 rats by parenteral injection of the colon carcinogen azoxymeth‐ane (AOM) and allowed to develop for 4 weeks, when an average of 90‐100 aberrant crypt foci per colon were found in the methylene blue‐stained colon. Then, during the second 4 weeks of the experiment, aberrant crypts were allowed to further develop to a frequency of > 150 foci per colon, a time when multi‐crypt foci were observed. During this time we tested the inhibitory effects of 4 analgesic drugs and 2 differentiation agents for effects of aberrant crypt growth and development. We found the non‐steroidal anti‐inflammatory drugs piroxicam, aspirin and ibuprofen, but not acetaminophen, to be effective in suppressing aberrant crypt formation or the progression to foci of multiple aberrant crypts. Treatment with chemo‐suppressing agents 13‐cis‐retinoic acid (13‐cRA) and 4‐hydroxy‐phenretinamide (4‐HPR), known differentiating agents, however, did suppress expansion of aberrant crypt foci, with 13‐cRA being the much more potent agent.
Catechol interferes with TGF‐β‐induced elimination of transformed cells by normal cells: Implications for the survival of transformed cells during carcinogenesis
Authors: Schaefer Dirk , M. Jürgensmeier Juliane , Bauer Gcorg
Published: February 2007

We have recently shown that TGF‐β‐treated normal fibroblasts are able to induce apoptosis of transformed fibroblasts, leading to their elimination. Here we describe a test system that allows the quantitative analysis of the elimination of G418‐resistant transformed cells by TGF‐β‐treated normal cells. This assay system was used to screen for substances that interfere with the elimination of transformed cells. Catechol and hydro‐quinone, but not resorcinol, were found to represent potent antagonists of TGF‐β‐induced elimination of transformed cells by normal cells. Protection of transformed cells from negative effects derived from their cellular environment defines a hitherto unrecognized crucial mechanism for the survival of transformed cells. The protective effect of catechol as seen in this experimental system may act in concert with its co‐carcinogenic and promoting activities during carcinogenesis.
Tumor‐promoting activity of 2,4‐dinitrofluorobenzene
Authors: Maldve Rcgina E. , Fischer Susan M.
Published: February 2007

The aim of this study was to determine whether the skin‐sensitizing agent 2,4‐dinitrofluorobenzene (DNFB) would elicit the same morphological and biochemical events that are characteristic of 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA). While single applications of 0.1% or 0.2% DNFB produced only mild epidermal hyperplasia, multiple applications produced pronounced hyperplasia. Compared with TPA, a single application of DNFB produced small increases in ODC activity, although a second DNFB treatment produced a greater response. Both DNFB and TPA caused marked induction of ODC, c‐fos and c‐jun mRNA. Vascular permeability increased significantly in response to DNFB, such that after 15 hr the response was quantitatively the same as for TPA. Repeated TPA produced the same response as a single application, but repeated DNFB resulted in a response that was half that of TPA. In contrast to TPA, DNFB failed to activate partially purified protein kinase C (PKC), although it did cause transient down‐regulation of activity 15 hr after treatment. The ability of DNFB to induce ODC activity, however, was unaffected by prior down‐regulation of PKC. DNFB was also shown to promote tumors in initiated SSIN mice. Twice‐weekly applications of 0.1 % or 0.2% DNFB resulted in approximately 65% and 85% of the mice developing an average of 2.0 or 3.2 tumors each, respectively. These results demonstrate that DNFB elicits many of the same changes as TPA and that it does so in a PKC‐independent manner.
Induction of ICAM‐1 and LFA‐3 by Tax1 of human T‐cell leukemia virus type 1 and mechanism of down‐regulation of ICAM‐1 or LFA‐1 in adult‐T‐cell‐leukemia cell lines
Authors: Tanaka Yoshikazu , Fukudome Kenji , Hayashi Masahito , Takagi Shin , Yoshie Osamu
Published: February 2007

The present study was undertaken to determine the role of HTLV‐I TaxI in the up‐regulation of ICAM‐1 and LFA‐3 in human T cells transformed with HTLV‐I and the mechanism of down‐regulation of ICAM‐1 and LFA‐I in ATL‐derived cell lines. Induction of Taxl in a human T‐cell line Jurkat carrying the Taxi gene under the metallothionein promoter led to increases in mRNA and surface expression of ICAM‐1. The response of LFA‐3 to Taxl induction was, on the other hand, relatively slow and weak, and might be indirect. Transactivation of the ICAM‐1 promoter by Taxl was further shown by co‐transfection of a CAT reporter construct with the ICAM‐1 promoter and a plasmid expressing Taxl. The mechanism of down‐regulation of ICAM‐1 or LFA‐1 in 4 ATL cell lines was next examined. ICAM‐1 mRNA was quite low in MT‐1, but no genomic changes were found. The CAT reporter with the ICAM‐1 promoter was inactive in MT‐1. Finally, combined treatment of MT‐1 with 5‐azacytidine and IFN‐γ induced re‐expression of ICAM‐1. Collectively, (a) transcriptional factor(s) necessary for expression of ICAM‐1 gene may be repressed in MT‐1 through DNA methylation. Three other ATL cell lines (TL‐Oml, H582, HuT 102) were found to have little mRNA for the LFA‐1 β chain (CD 18). H582 and HuT 102 were also negative for the LFA‐1 α chain (CDI la) mRNA. No genomic changes were found, and a CAT reporter gene with the CD 18 promoter was inactive in the 3 of them, again suggesting lack of (a) transcriptional factor(s) necessary for CD 18 expression.
Decreased macrophage‐mediated cytotoxicity in mammary‐tumor‐bearing mice is related to alteration of nitric‐oxide production and/or release
Authors: Sotomayor Eduardo M. , Dinapoli Michael R. , Calderón Cesar , Colsky Arthur , Fu Yang‐Xin , Lopez Diana M.
Published: February 2007

Peritoneal‐exudate macrophages (PEM) from mammarytumor‐bearing mice have impaired cytotoxic activity against syngeneic and allogeneic tumor targets. The ability of PEM from normal and tumor‐bearing mice to bind tumor targets was found to be similar in the presence or the absence of surrogate receptors, which enhanced the binding but not the killing of tumor targets by PEM from tumor‐bearing mice, suggesting that other mechanisms are involved in their impaired cytolytic activity. Soluble and membrane‐bound TNF‐α, as well as H2O2, were found in higher amounts in PEM from tumor bearers upon stimulation with LPS, as compared with PEM from normal mice. However, tumor‐bearers' macrophages displayed decreased capacity to produce and/or release nitric oxide, which could be reversed by the addition of increasing levels of IFN‐γ. These results indicate that the lack of macrophage cytotoxicity in mammary‐tumor‐bearing mice is related to impaired production and/or release of NO by these effector cells, possibly aggravated by the insufficient IFN‐γ production previously reported in these animals. Moreover, mammary‐tumor progression results in dis‐regulation of synthesis of macrophage‐mediators, with over‐production of molecules to which mammary‐tumor cells are insensitive and deficient production of NO, the crucial molecule to which these cells appear to be highly sensitive.
Clinical characteristics of metachronous colorectal tumors
Authors: Rennert G. , Robinson E. , Rennert H. S. , Neugut A. I.
Published: February 2007

A cancerregistrybased study was conducted to investigate the survival patterns associated with metachronous colorectal tumors and to compare the survival of patients with single and metachronous colorectal tumors. The study included all 1,396 White patients with metachronous colorectal tumors diagnosed among 143,283 patients with primary colorectal tumors reported between 1973‐1986 to the SEER program. The influence on survival of age at diagnosis, site of tumor and stage was evaluated by means of multivariate survival analysis, using Cox Proportional Hazards Models. Metachronous tumors developed more often following leftcolon tumors. Stage distribution of the second tumors was better than that of single tumors but 47% of the second tumors were discovered in regionallyadvanced or distantmetastatic stages. Survival from the second tumor diagnosed in the rectum was worse than that of a single tumor in the same stage and site. Only the stage of the second tumor was found to influence survival from metachronous tumors. The relatively high rate of diagnosis of advanced second colorectal tumors may reflect either improper followup after the diagnosis of the first tumor, or more aggressive biological characteristics of the second tumors. © 1995 Wiley‐Liss, Inc.
Possible significance of VLA‐4 (α β1) for hematogenous metastasis of renal‐cell cancer
Authors: Tomita Yoshihiko , Saito Toshihiro , Saito Kazuhide , Oite Takashi , Shimizu Fujio , Sato Shotaro
Published: February 2007

Very late antigen‐4 (VLA‐4) composed of α and β, a member of the β ‐integrin subfamily, facilitates cell‐to‐cell interaction with vascular celladhesion molecule‐1 (VCAM‐1) on endothelial cells (EC). Attachment of bloodborne tumor cells to EC is a crucial step for hematogenous metastasis, and VLA‐4‐positive tumor cells can attach to EC by binding to VCAM‐1. Renalcell cancer (RCC) reveals proportionally greater percentages of metastases than other carcinomas at initial diagnosis. We investigated whether VLA‐4 is expressed on RCC, and how such expression on RCC correlates with the metastatic potential of RCC. Immunohistochemical staining on 66 primary and 4 metastatic RCC showed that 4 out of 4 metastatic and 5 out of 8 primary RCC from patients with lung and /or brain metastases expressed α4 and β1 chains. On the other hand, 13 of 58 RCC without metastases expressed α4 chain. α4 and β expressions were also detected on 5 out of 5 human RCC cell lines, ACHN,KRC/Y, A498, Caki1 and Caki2, by flowcytometric analysis. Reversetranscriptasepolymerasechainreaction (RT‐PCR), followed by Southernblot hybridization with cDNA probe for a α4 chain, also confirmed mRNA production in 4 out of 5 RCC cell lines. Furthermore, adhesion of α4‐positive RCC cell lines to human umbilicalvein endothelial cells (HUVEC) was augmented by treatment of HUVEC with tumor necrosis factor‐α (TNF‐α). This adhesion was inhibited by anti‐α4 or anti‐VCAM‐1 antibodies, suggesting that VLA‐4‐VCAM‐1 interaction was involved in the adhesion between RCC cells and HUVEC. Taken together, VLA‐4 on RCC cells might play a crucial role in their hematogenous metastasis. © 1995 Wiley‐Liss. Inc.
Purification and characterization of a new 85‐kDa glycoprotein antigen from human breast tumor
Authors: Pal Saumitra , Sanyal Utpal , Chattopadhyay Utpala
Published: February 2007

A new breasttumorassociated antigen (BTAA) was purified and partially characterized from human breast tumor. By DEAE‐cellulose discontinuous NaCl‐gradient chromatography of a crude extract of human malignant breast tumor, 3 major protein peaks were obtained. Circulating antibodies against one of the protein peaks, HF1, was observed in breastcancer patients. The antibodies were absent in patients with carcinoma of the uterine cervix, lung, stomach and liver or with benign breast diseases and in healthy women. Absorption of the sera of breastcancer patients with normal human breast tissue pellet did not remove the HF1‐reactive circulating antibodies. The BTAA was partially purified from HF1 by subjecting the fraction to SDS‐PAGE and eluting the band 3 (HF1‐3). Westernblot analysis confirmed the presence of the BTAA in HF1‐3. Using an affinity column of protein‐A‐Sepharosebound IgG, purified from breastcancer patients' sera, the BTAA was also recovered from HF1. Purification of the BTAA was achieved by subjecting HF1 to sizeexclusion highperformance liquid chromatography (SE‐HPLC). The antigen was characterized as a glycoprotein with MW of approximately 85 kDa and appeared not to be related either to murine mammarytumor virus (MuMTV) structural antigens or to human fetal antigens. The BTAA‐reactive circulating antibodies in the breastcancer patients were of lgG2 subtype, and the level of these antibodies significantly decreased in patients following surgical removal of the breast tumors. © 1995 Wiley‐Liss, Inc.
Interleukin 2 receptor expression and interleukin 2 localisation in human solid tumour cells in situ and in vitro: Evidence for a direct role in the regulation of tumour cell proliferation
Authors: McMillan D. N. , Kernohan N. M. , Flett M. E. , Heys S. D. , Deehan D. J. , Sewell H. F. , Walker F. , Eremin O.
Published: February 2007

Frozen sections of 52 human solid tumours (38 malignant and 14 benign) of varied histogenesis were immunohistochemically stained with well characterised monoclonal antibodies (MAbs) to human interleukin 2 (IL‐2) and the α and β chains of its receptor (R). In all malignant specimens, the tumour cells expressed the IL‐2R β subunit (p75) but not the IL‐2R α subunit (CD25). In 36 of 38 malignant tumours examined, there was conspicuous staining for IL‐2 in the tumour cell nuclei/nucleoli and perinuclear cytoplasm. In the human solid tumour cell lines G361 (melanoma), A549 (lung), MCF‐7 (breast) and WiDR (colorectal), both subunits of the IL‐2R appeared to be expressed, although the α subunit only weakly. Exogenous addition of human recombinant (r) interleukin 2 altered cell numbers in 3 of the 4 cell lines (WiDR was refractory). When grown in the absence of exogenously added rIL‐2, IL‐2 staining was observed in all cell lines. The pattern of distribution was similar to that exhibited by the tumour cells in situ (i.e., a nuclear/nucleolar localisation). In G361 melanoma cells, this IL‐2 staining was present in proliferating cells but disappeared as the cultures approached confluence. Addition of an IL‐2R β subunit blocking antibody to growing G361 cultures (grown in the absence of rIL‐2) resulted in a significant reduction in cell numbers. We propose, therefore, that the presence of immunoreactive IL‐2 and IL‐2R expression is characteristic of human malignant cells and that IL‐2 may play a role in the autocrine stimulation of proliferation of malignant cells, such as G361 melanoma cells. © 1995 Wiley‐Liss, Inc.
Nation‐wide breast cancer screening in the Netherlands: Support for breast‐cancer mortality reduction
Authors: De Koning Harry J. , Fracheboud Jacques , Boer Rob , Verbeek André L. M. , Collette Hubertine J. A. , Hendriks Jan H. C. L. , Van Ineveld B. Martin , De Bruyn Arry E. , Van Der Maas Paul J.
Published: February 2007

The nationwide 2‐yearly breastcancer screening programme in The Netherlands, for women aged 50‐69, started around 1988, and was predicted to result eventually in a 16% reduction in breastcancer mortality in the total female population. We present the results of screening up to January 1, 1993, and compare these with the predicted results from the costeffectiveness analysis, on which basis this mortality reduction had been calculated. At least 550,000 women aged 50‐69 were invited to screening in 1990‐1992, and 75% of these participated. Cancer was suspected from 5,162 examinations and further investigation was therefore required. Excision biopsy was done in 72% of referrals, and 2,515 breast cancers were detected. The results for 404,000 newly invited women compare favourably with expected values (in parentheses): 78% attendance rate (70%), 1.4% screen positive (1.6%), 6.8 cancers detected per 1,000 women screened (6.4) and 38% of these cancers were DCIS or invasive carcinomas smaller than 11 mm in diameter (36%). More data, e.g., on treatment and interval cancers, will follow in the years to come. These first results can be interpreted as strong early signs of a reduction in breastcancer mortality of at least the predicted size. Screening has sufficiently advanced the diagnosis, as well as or better than expected. Breast cancers diagnosed in this age group without screening are diagnosed at a worse stage than expected. Unfavourable sideeffects, especially falsepositive referrals, might be kept lower than those reported in other countries. © 1995 Wiley‐Liss, Inc.
The lower level of natural anti‐thomsen‐friedenreich antigen (TFA) agglutinins in sera of patients with gastric cancer related to ABO(H) blood‐group phenotype
Authors: Kurtenkov Oleg , Klaamas Kersti , Miljukhina Ljudmila
Published: February 2007

The TFA is a tumorassociated, bloodgrouprelated glycosidic precursor structure [Gal(β1‐3)GalNAc]. Its expression in carcinomas is accompanied by a decrease of natural TFA antibodies in serum. The relationship between the ABO(H)‐bloodgroup phenotype and natural anti‐TFA immune response in patients with gastric cancer was studied. The level of TFA agglutinins in the sera of patients with gastric cancer and of healthy controls was examined by the hemagglutination of neuraminidasetreated bloodgroup‐O donor erythrocytes. Individuals were classified as weak or strong TFA responders. They were also classified by ABO(H)‐bloodgroup status, age, cancer stage, tumor morphology and level of isohemagglutinins. The proportion of weak TFA responders (WR) in cancer patients was 33, 50, 50 and 20% (for O, A, B and AB blood groups respectively), as compared with 11.7, 14.5, 13.9 and 26.1% for bloodgrouprelated controls. The difference between cancer patients and controls was significant for all blood groups except group AB. Further analysis showed agedependence in bloodgroup‐O and ‐B controls, with a high level of WR in the older group. Bloodgroup‐A cancer patients had the greatest and uniform suppression of the level of TFA agglutinins, irrespective of age, cancer stage or tumor morphology, and lower levels of anti‐B isohemagglutinins. © 1995 Wiley‐Liss, Inc.
Chromosomal abnormalities in glioblastoma multiforme tumors and glioma cell lines detected by comparative genomic hybridization
Authors: Kim Dong H. , Mohapatka Gayatry , Bollen Andrew , Waldman Frederic M. , Feuerstein Burt G.
Published: February 2007

Comparative genomic hybridization (CGH) is a recent molecular cytogenetic method that detects and localizes gains or losses in DNA copy number across the entire tumor genome. We used CGH to examine 9 glioma cell lines and 20 primary and 10 recurrent glioblastoma tumors. More than 25% of the primary tumors had gains on chromosome 7; they also had frequent losses on 9p, 10, 13 and Y. The losses on chromosome 13 included several interstitial deletions, with a common area of loss at 13q21. The recurrent tumors not only had gains on chromosome 7 and losses on 9p, 10, 13 and Y but also frequent losses on 6 and 14. One recurrent tumor had a deletion of 10q22‐26. Cell lines showed gains of 5p, 7 and Xp; frequent amplifications at 8q22‐24.2, 7q2l‐32 and 3q26.2‐29 and frequent losses on 4, 10, 13, 14 and Y. Because primary and recurrent tumors and cell lines showed abnormalities of DNA copy number on chromosomes 7, 10, 13 and Y, these regions may play a fundamental role in tumor initiation and/or progression. The propensity for losses on chromosomes 6 and 14 to occur in recurrent tumors suggests that these aberrations play a role in tumor recurrence, the development of resistance to therapy or both. Analysis of common areas of loss and gain in these tumors and cell lines provides a basis for future attempts to more finely map these genetic changes.
Oesophageal cancer in never‐smokers and never‐drinkers
Authors: Cheng K. K. , Duffy S. W. , Day N. E. , Lam T. H.
Published: February 2007

Alcohol, tobacco and diet are the most important determinants of oesophageal cancer. Previous studies which examined smoking in non‐drinkers and drinking in non‐smokers did not report the main effects of dietary factors or the smoking and drinking effects adjusted for dietary factors. Data from a hospital‐based case‐control study in Hong Kong Chinese were used to examine the effects of dietary variables as well as tobacco and alcohol in never‐drinkers and never‐smokers. Among the 400 cases, there were 68 never‐smokers and 53 never‐drinkers; 540 were never‐smokers and 407 were neverdrinkers among 1598 controls. In never‐smokers, alcohol drinking was strongly associated with risk. Use of green leafy vegetables and citrus fruits was protective. Among neverdrinkers, smokers had increased risk, but the protective effect of vegetables and fruits did not reach statistical significance. In never‐smokers and in never‐drinkers alike, frequent consumption of pickled vegetables and being born in Teochew or Hokkien were associated with increased risks. This study provides further support for the independent effects of alcohol, tobacco and diet in oesophageal cancer. © 1995 Wiley‐Liss, Inc.
Promotion of experimental liver metastasis by tumor necrosis factor
Authors: Orosz Peter , Krüger Achim , Hubbe Marcus , Rüschoff Josef , Hoegen Paul Von , N. Männel Daniela
Published: February 2007

Models for experimental metastasis were established to investigate the influence of rmTNF on tumor‐colony formation in the liver. Highly metastatic lymphoma tumor cells were either injected i.v. or inoculated s.c. to form spontaneous metastases. In both systems, administration of rmTNF to the animals led to significant enhancement of the number of liver metastases in comparison with control groups. The number of metastatic tumor‐cell colonies at an early stage of metastasis was increased, as well as the number of surface metastases in a late stage. Consequently, TNF‐treated animals revealed a higher mortality. The optimal time for TNF to exert this metastasis‐enhancing effect was found to be 7 days after tumor inoculation, In vitro adhesion of the lymphoma tumor cells to a mouse endothelioma cell line was strongly inhibited by monoclonal antibodies interfering with the interaction of VCAM‐1 with VLA‐4. These results support and extend earlier results with a fibrosarcoma lung colonization model. In addition, they show that stimulation of the immune system in tumor‐bearing hosts activates tumor‐promoting pathways, in addition to having possible beneficial effects.
Analysis of the p53 gene in relation to tobacco and alcohol in cancers of the upper aero‐digestive tract
Authors: Franceschi S. , Gloghini A. , Maestro R. , Barzan L. , Bidoli E. , Talamini R. , Vukosavuevic T. , Carbone A. , Boiocchi M.
Published: February 2007

To elucidate the relationship, if any, of p53 gene expression according to smoking and drinking habits, 135 subjects with cancer of the upper aero‐digestive tract were sampled from a case‐control investigation conducted in Pordenone province, Northeast Italy, between 1986 and 1991. Adequate pathological material for immunohistochemical analysis was available for 83 subjects. Level of p53 expression was classified according to intensity on immunoreaction and percentage of p53‐positive cells. Mutations were analyzed by means of single‐strand conformation polymorphism and sequencing in 8 p53‐positive life‐long non‐smokers exposed to various levels of alcohol intake. The association between p53 expression and smoking status and alcohol intake was evaluated by means of odds ratios, and 95% confidence intervals. Significantly, more men (39/65) than women (6/18) had elevated p53 expression. No significant trend of increasing percentage of p53‐positive cancers with increasing smoking and drinking level was detected, especially after allowance for gender. With respect to specific mutation pattern, in 8 life‐long non smokers who drank alcohol, 6 mutations involved G:C base pairs. G‐to‐A transitions were identified in 4 cases. The present study does not support an association between elevated p53 expression and tobacco smoking or alcohol intake. It provides an example of a molecular biology study in the framework of a large epidemiological investigation.
Organisation and gel contraction by human colonic carcinoma (HCA‐7) sublines grown in 3‐dimensional collagen gel
Authors: Kirkland Susan C. , Henderson Karen , Liu Dan , Pignatelli Massimo
Published: February 2007

The role of cell‐matrix interactions in controlling phenotypic heterogeneity in human colonic carcinoma sublines has been investigated. Four cell lines (colony 1, colony 3, colony 6 and colony 30) previously isolated from a single human colonic carcinoma cell line, HCA‐7, were grown in 3‐dimensional collagen gels. In collagen, the growth of the 4 sublines ranged from well‐organised glandular structures (colony 30) to elongated branching structures (colony 3). The capability of cells to organise into glandular structures in collagen correlated with the degree of differentiation observed in their xenografts. Certain sublines, most notably colony 3, were able to contract the collagen gel. Gel contraction could be partially inhibited by a function‐blocking antibody directed to the α2 integrin chain but not by an antibody directed to the α3 integrin chain demonstrating a role for α2 integrin in the contraction process. In addition, colony 3 cultures treated with the function‐blocking α2 antibody formed more compact structures with limited outgrowth, suggesting a role for α2 integrin in cell migration. Gel contraction and cell migration in collagen gel was largely restricted to 1 subline, colony 3. The subsequent demonstration that α2 integrin is involved in both of these processes suggests that integrin expression and function has a role in generating the phenotypic heterogeneity exhibited by these cell lines.
Identification of genital human papillomaviruses in cervical biopsy specimens: Segregation of specific virus types in specific clinicopathologic lesions
Authors: Matsukura Toshihiko , Sugase Motoyasu
Published: February 2007

We have established a critical identification method for the full spectrum of genital human papillomaviruses (HPVs) in clinical specimens. It was based on the recognition of Pstl, Banl and Mspl cleavage patterns of HPV DNA detected by blot hybridization with HPV 58 DNA probe at Tm—40°C. By this method, we identified 24 different types of genital HPV including 5 novel types (HPV 59, 61, 62, 64 and 67) in the specimens collected at one hospital and found almost all the HPVs with the authentic cleavage patterns of their respective prototypes. In 235 cervical biopsy specimens, HPV 6 or 11 was found in exophytic condyloma acuminatum (15/15) but not in any cervical intraepithelial neoplasia (CIN) specimens. In contrast, HPV 18, 30, 43, 54, 56, 59, 62, 66 and 67 were identified in CIN I (28/71) or II (4/56) but not in CIN III, while HPV 16, 31, 33, 35, 39, 51, 52 and 58 were identified in CIN III (83/93) as well as in CIN I (34/71) and II (47/56). The result indicates that heterogeneous genital HPVs prevail all over the world. In addition, HPV 6 and 11 are etiologic agents only of exophytic condyloma, whereas the other HPVs are etiologic agents of CIN with the segregation of specific HPVs in CIN III. We propose a new clinicopathologic grouping of genital HPVs founded on nucleotide homology of the HPV genome. © 1995 Wiley‐Liss, Inc.
Multiple forms of cathepsin b in human lung cancer
Authors: Křepela Evžen , Procházka Jan , Mynaříková Helena , Kárová Bohdana , Polák Jaroslav , Čermák Jan , Roubková Helena
Published: February 2007

In this study we have examined, by means of isoelectric focusing (IEF) in native polyacrylamide gel and contact‐print fluorescence zymography, whether human lung carcinomas and the lung parenchyma contain different pools of multiple charge forms of the cysteine proteinase cathepsin B. The isoelectric point (pl) patterns of cathepsin B from lung carcinoma and matched lung were similar, particularly with regard to 2 major intermediate acidic enzyme pl forms designated as I and II (plapp of 5.10 and 4.93 in tumors, and 5.11 and 4.94 in lungs, respectively). The slightly acidic cathepsin B pl forms (plapp 5.47–5.19) in squamous‐cell lung carcinoma (SQCLC) were significantly more numerous than such enzyme pl forms in lungs. The numbers of the highly acidic cathepsin B pl forms (plapp 4.82–4.33) were significantly higher in SQCLC and lung adenocarcinoma (ACL) than in matched lung. The activity distribution percentage in the set of highly acidic cathepsin B pl forms was significantly higher in SQCLC and ACL than in matched lung. We also observed that cathepsin B from SQCLC and matched lung was fully recoverable by IEF from inhibition by leupeptin. Using the cysteine‐proteinase‐specific inactivator E‐64, we revealed by IEF that some cathepsin B isoforms (charge forms) from SQCLC were more resistant to inactivation by this compound than the corresponding enzyme isoforms from lungs. After IEF, the enzyme isoforms apparently lost their resistance to E‐64. Our results indicate that the pool of multiple charge forms of cathepsin B in SQCLC and ACL is different from that in the lung, and also that there may be an increased level of loose complexes between cathepsin B and some proteins or polypeptides in SQCLC compared to the lung. © 1995 Wiley‐Liss Inc.
Regulation of cytoskeletal organization in tumor cells by protein phosphatases‐1 and ‐2A
Authors: Maier George D. , Wright Mark A. , Lozano Yvonne , Djordjevic Andelka , Matthews John P. , Young M. Rita I.
Published: February 2007

Non‐metastatic Lewis lung carcinoma cells (LLC‐C8) become more motile when protein phosphatases (PP‐1 and ‐2A) are inhibited by okadaic acid, attaining the same level of motility as metastatic LLC (LLC‐LN7) variants. This stimulation of LLC‐C8 motility was tempered when protein kinase A activity was inhibited. We examined whether the okadaic acid–stimulated LLC‐C8 motility was associated with alterations in the cytoskeletal organization so that these non‐metastatic cells acquire the rounded morphology and diffuse cytoskeletal organization previously described for metastatic LLC‐LN7 cells. Non‐metastatic LLC‐C8 are typically adherent during culture, achieving a spread morphology. Treatment of non‐metastatic LLC‐C8 cells with okadaic acid resulted in a contraction of most of their extended processes, formation of spikes and membrane blebs within 10 min, and complete cell rounding within 20 min for most of the cells. While the overall level of F‐actin was minimally affected by the okadaic acid, its uniform distribution shifted to localization toward the periphery of the rounded cells, often concentrating at a single focus. Immunofluorescent staining for vimentin showed a similar shift to the cell periphery and similar capping. After okadaic acid treatment, the filamentous network of microtubules in non‐metastatic LLC‐C8 cells disappeared and was replaced with a diffusely staining distribution of β‐tubulin. These results show that PP‐1 and‐2A maintain cytoskeletal organization and that inhibition of this control reduces cytoskeletal organization and increases tumor cell motility. © 1995 Wiley‐Liss, Inc.
The role of TGF‐β production in growth inhibition of breast‐tumor cells by progestins
Authors: Kalkhoven Eric , Kwakkenbos‐Isbrücker Linda , Mummery Christine L. , De Laat Siegfried W. , Van Den Eijnden‐Van Raaij Adriana J. M. , Van Der Saag Paul T. , Burg Bart Van Der
Published: February 2007

We have studied the influence of synthetic progestins on the estrogen‐induced proliferation and type‐β transforming‐growth‐factor (TGF‐β) production of 3 breast‐tumor cell lines. In long‐term growth experiments, progestins inhibited proliferation of T47D cells, while a specific T47D variant and MCF7 cells were not affected, despite the presence of functional progesterone receptors. The effect of progestins was biphasic, since an initial stimulation of proliferation was followed by a prolonged inhibition. This response suggests the involvement of a progestin‐induced negative growth regulator. We show here that TGF‐βs do not fulfill this role since (i) the progestin‐induced T47D cells are not sensitive to TGF‐βI, ‐β2 or ‐β3, (ii) secretion of TGF‐βs is decreased by progestins in all 3 cell lines, and (iii) TGF‐β neutralizing antibodies do not reverse progestin‐induced growth inhibition. Furthermore, evidence was obtained that medium conditioned by T47D cells does not contain any other growth inhibitor to which this cell line responds in a negative autocrine manner. In contrast, MCF7 cells are growth‐inhibited by all 3 TGF‐β isoforms, but are not growth‐inhibited by progestins, suggesting that there is no correlation between growth inhibition by progestins and responsiveness to and production of TGF‐β in vitro. Although TGF‐β is a strong growth inhibitor of normal mammary tissue, recent evidence suggests that, in malignant tissue, enhanced TGF‐β secretion correlates with increased malignancy. Therefore, a progestin‐induced decrease in TGF‐β production, as observed here, may lead to enhanced proliferation of normal but not malignant mammary epithelium. © 1995 Wiley‐Liss, Inc.
Aberrations of p16Ink4 and retinoblastoma tumour‐suppressor genes occur in distinct sub‐sets of human cancer cell lines
Authors: Aagaard Louise , Lukas Jiri , Bartkova Jirina , Kjerulff Anne‐Arnt , Strauss Michael , Bartek Jiri
Published: February 2007

The p16Ink4/MTSI/CDKN2 is a cell‐cycle regulatory inhibitor of cyclin‐dependent kinase 4 (cdk4), and a candidate tumour suppressor whose gene on chromosome band 9p21 is frequently deleted or mutated in diverse types of cancer. Cdk4 in association with its D‐type cyclin partners, together with p16Ink4, and the product of the retinoblastoma tumour‐suppressor gene (pRB), appear to constitute a G1‐phase‐controlling pathway which can become de‐regulated through oncogenic aberrations of any of the components. In an attempt to elucidate the underlying molecular mechanisms, we have now surveyed expression of p16Ink4, at the protein and the mRNA levels, in 21 human cell types expressing normal pRB, as compared with another series of 21 cell lines whose pRB is mutant and/or inactivated through sequestration by DNA tumour virus onco‐proteins. In contrast to aberrant lack of p16 expression in the majority of RB‐positive cell types, expression of apparently normal (as shown by electrophoretic mobility and/or the ability to form protein‐protein complexes with cdk4 in vivo) p16 was uniformly preserved in the cancer cell lines whose RB function was compromised. These data indicate that p16 operates upstream of pRB along the same pathway in G1. The results are discussed in view of the nature of a selective growth advantage potentially gained by cells through de‐regulation of this key cell‐cycle control mechanism. © 1995 Wiley‐Liss, Inc.
Descriptive epidemiology of oral neoplasms in sudan 1970‐1985 and the role of toombak
Authors: Idris A. M. , Ahmed H. M. , Mukhtar B. I. , Gadir A. F. , El‐Beshir E. I.
Published: February 2007

Data from 1,916 cases of oral neoplasms occurring in the Sudan in a 16‐year period, from January 1970 to December 1985, were retrieved and analysed. The study revealed a relatively high frequency of oral neoplasms in comparison with neighbouring countries. In this study, squamous‐cell carcinoma was the most common oral malignancy (66.5%), followed by tumours of the salivary gland (14.7%), neoplasms of non‐odontogenic and non‐epithelial origin (9.6%) and odontogenic neoplasms (8.6%). Men had a higher frequency than women. The older age group of both genders showed a relatively high frequency of squamous‐cell carcinoma. Among northern Sudanese there was a high rate of squamous‐cell carcinoma, while southern Sudanese showed a high rate of odontogenic and salivary‐gland neoplasms. The use of toombak has been stated to play a major role in the aetiology of oral squamous‐cell carcinoma in the Sudan, and is suspected to be associated with neoplasms of the salivary glands. © 1995 Wiley‐Liss, Inc.
Detection of two epstein‐barr‐virus (EBV)‐carrying leukemic cell clones in a patient with chronic lymphocytic leukemia (CLL)
Authors: Lewin Nongnit , Avila‐Cariño Javier , Minarovits Janos , Lennette Evelyne , Brautbar Chaim , Mellstedt Håakan , Klein George , Klein Eva
Published: February 2007

The leukemic‐cell population of one CLL patient, PG, was found to contain a sub‐set of EBV‐genome‐carrying cells. It was detected directly by the expression of EBNA (EBV‐encoded nuclear antigen) and by its capacity to grow in vitro. The proportion of EBNA‐positive cells (0.1%) was maintained constantly during the period of this study, the final 3 years of the patient's life. EBV‐carrying clonal sibling B‐cell lines were established on 5 occasions. They had identically rearranged JH bands and chromosomal markers corresponding to the ex vivo CLL cells. Analysis of the viral episomes in the lines proved that they were the descendants of one cell. On the last occasion of blood sampling, 8 B‐cell lines were established; 4 of these contained the same clonal markers as the previous lines, while 4 other lines belonged to another clone with identical JH rearrangement. Their abnormal karyotypes were different from the first clone. The chromosomal markers were only partly identical, suggesting secondary diversifications. The EBV sub‐strain carried by this group of lines was different from the sub‐strain of the first clone, as judged by the EBNA size distributions (EBNOtype) and EBV‐DNA analysis. Analysis of the terminal repeat in the viral episomes also showed that the first and the second set of clones represented 2 independent EBV‐infection events in vivo. © 1995 Wiley‐Liss, Inc.
Sensitive detection of numerical and structural aberrations of chromosome 1 in neuroblastoma by interphase fluorescence in situ hybridization. comparison with restriction fragment length polymorphism and conventional cytogenetic analyses
Authors: Combaret Valérie , Turc‐Carel Claude , Thiesse Philippe , Rebillard Anne‐Catherine , Frappaz Didier , Haus Odile , Philip Thierry , Favrot Marie C.
Published: February 2007

Chromosome 1 abnormalities are indicators of prognosis in neuroblastoma (NB) but are not yet routinely exploited because conventional methods are technically demanding. We evaluated the pertinence of interphase cytogenetics fluorescence in situ hybridization (FISH) for the analysis of chromosome 1 in NB, compared with conventional methods. Deletion of 1p was detected in 8 of 9 cell lines analyzed by both FISH and restriction fragment length polymorphism (RFLP), but was evidenced in only 2 cases by conventional cytogenetics, painting analysis being required to reveal the other cases. The chromosome 1 number evaluated by FISH reflected the total chromosome modal number obtained by cytogenetics. Twenty‐eight specimens obtained from ultrasound‐guided punctures, surgical biopsies of the primary tumor and bone‐marrow aspirates were studied by FISH on frozen cytocentrifuged smears; 12 had a chromosome 1 trisomy and 16 a disomy. Requirements for a reliable control analysis of 1p deletion by RFLP were met in only 23 cases. The retention of 2 alleles was observed in 15 cases and 1p deletion in 7, by both techniques. In one case, an interstitial deletion of 1p was evidenced only by RFLP, and one of 5 cases analyzed only by FISH had a 1p deletion. Although FISH might be improved by using additional probes, it presents major advantages for routine exploitation. Determining 1p deletion in individual cells makes it possible to analyze small and heterogeneous tumoral specimens; the technique requires only a few hours and can easily be standardized in non‐specialized laboratories. The number of chromosome 1 homologues per cell might serve as a rapid screening for ploidy. © 1995 Wiley‐Liss, Inc.
Direct tumorigenic conversion of human gallbladder carcinoma cells by v‐src but not by activated c‐H‐ras oncogene
Authors: Tatsumoto Takashi , Nakano Shuji , Shimizu Kenji , Ono Mayumi , Esaki Taito , Ohshima Koh‐Ichi , Niho Yoshiyuki
Published: February 2007

The roles of activated ras and src oncogene products in the acquisition of fully neoplastic phenotype by human gallbladder adenocarcinoma cells were investigated by co‐transfecting non‐tumorigenic HAG‐1 human gallbladder carcinoma cells with the pSV2neo plasmid and a plasmid carrying either activated c‐H‐ras or v‐src oncogene. G‐418‐resistant clones were isolated and assessed for the acquisition of anchorage‐independent growth potential. Neither the 10 established clones transfected with pSV2neo alone nor the 17 clones transfected with activated c‐H‐ras, including 4 clones expressing the mutated p21H‐ras protein, could form colonies in soft agar. By contrast, out of 10 clones transfected with v‐src, 2 formed colonies in soft agar and produced tumors in athymic nude mice, the resulting progressive neoplasms being poorly differentiated adenocarcinomas. These tumorigenic clones were shown to have v‐src DNA and mRNA levels with p60v‐src protein, but there were no significant chromosomal alterations following tumorigenic conversion. Moreover, herbimycin A, a selective src‐kinase inhibitor, markedly reduced clonogenic growth of these cells in soft agar rather than monolayer growth, suggesting that anchorage‐independent growth of the v‐src‐transformed HAG‐1 cells might be driven directly by p60v‐src kinase activity. Taken together, our data suggest that the fully neoplastic conversion of HAG‐1 cells depends on src‐related tyrosine‐kinase activity, but not solely on the function mediated by activated ras, thus providing evidence of an src‐related signaling pathway for the acquisition of tumorigenic potential by human gallbladder adenocarcinoma cells. © 1995 Wiley‐Liss, Inc.
Hypergastrinemia in rats with azoxymethane‐induced colon cancers
Authors: D'Agostino Luciano , Pignata Sandro , Tritto Giovanni , D'Adamo Giuseppe , Contegiacomo Alma , Daniele Bruno , Calderopoli Rita , Pizzi Claudia , Squame Giovanni , Mazzacca Gabriele
Published: February 2007

Gastrin has been suggested to be involved in the promotion and progression of colon cancer. Mice colon cancers and colon‐carcinoma cell lines are stimulated to grow by gastrin, and gastrin receptors have been found in the majority of human colon‐tumor specimens. High serum gastrin levels have been reported in patients with colon polyps and cancers, together with increased ornithine decarboxylase (ODC) activity. Since gastrin stimulates ornithine decarboxylase in colon cancer cells in vitro it has been suggested that increased synthesis of intracellular polyamines is one of the mechanisms activated by the hormone. In order to confirm the presence of hypergastrinemia in colon cancer and to investigate the relationship between plasma gastrin and tumor growth, we used an animal model of colon carcinogenesis that minimizes the possible bias of human studies, related to varying diet, age and environmental factors. We evaluated blood gastrin levels in 35 rats with colon cancer induced by the carcinogen azoxymethane (AOM), and we correlated gastrinemia with tumor proliferation, assessed by thymidine‐labeling index (TLI) and ODC activity; 6 animals constituted the control group. Gastrin levels in rats with AOM‐induced tumors were significantly higher than in controls. Significantly higher TLI and ODC activity were found in the tumors of hypergastrinemic rats than in neoplasms of animals with normal gastrin levels. Our data provide additional evidence of a role for gastrin as trophic hormone for colon neoplastic cells. © 1995 Wiley‐Liss, Inc.
Glycoconjugate profile and cd44 expression in human melanoma cell lines with different metastatic capacity
Authors: Van Muijen Goos N. P. , Danen Erik H. J. , Veerkamp Jacques H. , Ruiter Dirk J. , Lesley Jayne , Van Den Heuvel Lambert P. W. J.
Published: February 2007

Changes in glycoconjugate production have been reported for tumor cells. In this study, we investigated the glycoconjugate expression pattern in normal human melanocytes and in a panel of 6 human melanoma cell lines with different metastatic capacity after s.c. inoculation into nude mice. Glycoconjugates were labeled in vitro with [35S] sulphate and [3H] glucosamine, purified from cells and culture medium by column chromatography and identified by treatment with specific glycosidases. Characterization of the purified glycoconjugate fractions as well as alcian‐blue staining of xenograft lesions revealed that hyaluronic acid (HA) is the main glycoconjugate produced by all cell lines. Highly metastatic cell lines expressed higher levels of HA than melanocytes and than weakly metastatic or non‐metastatic cell lines. In addition, a shift in dominance from chondroitin‐sulphate proteoglycan to heparan‐sulphate proteoglycan was observed with increasing metastatic capacity. We also studied the expression and binding activity of the HA receptor CD44. Immunoprecipitation experiments indicated high CD44 synthesis only in highly metastatic cell lines, but FACS analysis demonstrated approximately the same surface expression in melanocytes as in all cell lines. Adhesion assays to immobilized HA showed that CD44 can be present in an inactive or an active conformation. Our data suggest that a combination of increased HA production and the expression of CD44 on the cell surface may be associated with high metastatic potential of human melanoma cell lines in nude mice. © 1995 Wiley‐Liss, Inc.