bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and characterization of 5T4, a tumour‐associated antigen
Authors: Hole Nicholas , Stern Peter L.
Published: February 2007

The monoclonal antibody (MAb) 5T4 defines a human trophoblast antigen marker with a restricted pattern of expression in normal adult tissues but this antigen is expressed on a variety of carcinomas. The purification of 5T4 antigenic molecules is described from term syncytiotrophoblast by a combination of lectin‐ and immunoaffinity chromatography and gel filtration giving up to 10,000‐fold purification with 70% yield. The antigen is carried by non‐associated glycoprotein molecules with an apparent molecular weight of 72 kDa on SDS‐PAGE and a neutral pl. Removal of N‐linked sugars by N‐glycanase reveals a core protein of 42 kDa. Treatment with enzymes that cleave O‐linked sugars does not substantially alter the molecular size. The native 5T4 molecules are very resistant to proteolysis until the N‐linked sugars are removed or the glycoprotein is denatured and reduced. Glycopeptides generated by these approaches will be suitable for amino acid sequencing.
Vaccination against polyoma virus (PYV) tumors using vaccinia‐PYV recombinants: A major tumor‐specific transplantation antigen (TSTA) epitope resides within the C‐terminal segment of middle‐T protein
Authors: Kieny M. P. , Gautier C. , Tomasetto C. , Kuhn I. , Hareuveni M. , Clertant P. , Lathe R.
Published: February 2007

We previously reported that inoculation of rats with live vaccinia virus (VV) recombinants VVpyMT, VVpyLT expressing either the middle‐T (MT) or large‐T (LT) proteins of polyomavirus (PyV) can elicit immunity to challenge with syngeneic PyV‐tumor cells. We now report the results of cross‐vaccination studies. VVpyMT was ineffective against cells expressing LT protein but prevented development of MT‐expressing cells. Conversely, the VVpyLT was ineffective against MT‐expressing cells. In the two experiments performed, tumor growth enhancement rather than retardation was observed in VVpyLT‐vaccinated animals receiving PyV‐LT (FRLTI) challenge tumor cells. To determine the location of the major TSTA within MT, a further VV recombinant (VVpyMT/Cfr) was constructed that expresses only the unique C‐terminal segment of MT. VVpyMT‐Cfr and VVpyMT were equally effective in eliciting tumor immunity, indicating the presence of a major TSTA epitope within the unique C‐terminal region of MT.
Adeno‐associated parvoviruses inhibit growth of cells derived from malignant human tumors
Authors: Bantel‐Schaal Ursula
Published: February 2007

Infection of freshly established malignant human tumor cells with the adeno‐associated viruses AAV‐2 or AAV‐5 inhibits cell proliferation. Normal human fibroblasts are also affected, but appear to partially escape the inhibition. In cell cultures of permanent lines of human and rodent origin, cell number reduction could not be observed. The AAV‐mediated influence on cell growth is not due to helper‐independent replication of the virus, since neither of the cell cultures supported AAV propagation in the absence of a viral helper.
Prognostic significance of alpha‐1‐antitrypsin in early stage of colorectal carcinomas
Authors: Karashima Seiichiro , Kataoka Hiroaki , Itoh Hiroshi , Maruyama Riruke , Koono Masashi
Published: February 2007

We have previously shown that human colorectal carcinoma cell lines, RCM‐1 and CoCM‐1, synthesize alpha‐1‐antitrypsin (α1‐AT) in culture. We have studied immunohistochemically the incidence of α1‐AT on histologic sections from paraffin‐embedded tissues of surgically resected colorectal carcinomas and their metastatic foci, polypectomized adenomas, and normal mucosae. α1‐AT was detected in 89 (61%) of 145 carcinomas (including 14 carcinomas in adenoma), and 12 (39%) of 31 adenomas. But only 2 (4%) of 55 normal colorectal mucosae were positive for α1‐AT. In metastatic tumor cells of colorectal carcinomas in lymph nodes and other organs, α1‐AT positivity was 60% and 82%, respectively. The incidence of α1‐AT was markedly higher in advanced adenocarcinomas than in early ones and more frequent in adenocarcinomas of right side (including transverse colon) than those of left side and rectum, regardless of their histological malignancy grades. In mucinous carcinomas the frequency was greater (8 of 9 cases) than in conventional adenocarcinomas.

Clinical follow‐up of the patients with colorectal carcinomas suggested that α1‐AT positivity in Dukes' stage A/B tends to correlate with unfavorable prognosis irrespective of the grade of histologic differentiation of carcinoma, but there is no significant relation in Dukes' stage C/D. Our findings suggest that α1‐AT in colorectal carcinoma is related to the invasive and metastatic capacity. It may thus serve as a biologic marker for prognosis of colorectal carcinomas at relatively early stages (Dukes' stage A/B).
Overexpression of the MDRL gene in blast cells from patients with acute myelocytic leukemia is associated with decreased anthracycline accumulation that can be restored by cyclosporin‐A
Authors: Nooter Kees , Sonneveld Pieter , Oostrum Robert , Herweijer Hans , Hagenbeek Ton , Valerio Dinko
Published: February 2007

Typical multi‐drug resistance (MDR) in human and animal cell lines is caused by overactivity of a unidirectional drug efflux pump. This pump is composed of a 170‐kDa transmembrane glycoprotein (P‐glycoprotein) that is encoded by the so‐called mdrl gene. The functionally relevant characteristic of MDR cells is a defect in drug accumulation that can be restored by agents which inhibit the P‐glycoprotein pump. The purpose of our study was to find out whether Pglycoprotein inhibitors could increase the daunorubicin (DNR) accumulation in acute myelocytic leukemia (AML) cells, overexpressing the mdrl gene. Using dot blot analysis with an mdrl‐specific cDNA probe, we identified leukemic cell samples, obtained from chemotherapy‐resistant AML patients, that had relatively high levels of mdrl expression. These leukemic cells showed a reduced ability to accumulate DNR in vitro, as quantitated by flow cytometry. Addition of cyclosporin‐A (Cy‐A), a drug known to inhibit the P‐glycoprotein pump, to the incubation medium resulted in an increase (up to 60%) in steady‐state drug uptake by the leukemic cells. The degree of Cy‐A‐induced increase in drug accumulation in the leukemic cells correlated approximately with the level of overexpression of the mdrl gene. Our data indicate that Cy‐A is a good candidate for combination chemotherapy with cytotoxic drugs in clinical trials, aimed at the treatment of drug resistance in AML.
Comparison of dna cleavage induced by etoposide and doxorubicin in two human small‐cell lung cancer lines with different sensitivities to topoisomerase ii inhibitors
Authors: Binaschi Monica , Capranico Giovanni , De Isabella Paola , Mariani Mariangela , Supino Rosanna , Tinelli Stella , Zunino Franco
Published: February 2007

In an attempt to clarify the role of drug‐induced proteinassociated DNA breaks (i.e., DNA topoisomerase II‐mediated DNA cleavage) in the cytotoxic activity of doxorubicin and etoposide, their cellular effects were compared in 2 human small‐cell lung cancer (SCLC) lines, characterized by differential sensitivity to DNA topoisomerase II inhibitors. These drugs were selected for comparative studies since they are among the most effective agents in the treatment of SCLC. H146 and N592 cell lines were obtained from pleural effusion and bone‐marrow aspirate of pretreated patients, respectively. Both cell lines grew as floating aggregates with similar doubling times (30 and 33 hr for N592 and H146 cells, respectively). Although, immediately after 1 hr exposure to equitoxic drug levels, the extent of DNA cleavage produced by doxorubicin was markedly lower than that produced by etoposide, DNA lesions produced by doxorubicin persisted and even increased following drug removal. In contrast, an almost complete disappearance of etoposide‐Induced DNA breaks was noted 1 hr after drug removal. Resealing of strand breaks was faster in N592 than in H146 cells. These findings suggest that reversal of these lesions plays a major role in cell survival rather than the occurrence of DNA breaks immediately following drug exposure. This observation is consistent with the view that inhibition of DNA re‐ligation rather than stimulation of DNA cleavage is the critical step for drug action. The different response of these cell lines to cytotoxic action of the topoisomerase inhibitors is associated with a differential drug effect on DNA integrity (detected as DNA double‐strand breaks and DNA‐protein cross‐links). However DNA lesions were comparable when cells were exposed to equitoxic drug levels. The observation that etoposide‐induced DNA breaks were similar in isolated nuclei from both cell lines suggests that drug‐target interaction is modulated in a different manner in the intact cell. As indicated by doxorubicin uptake and retention, cellular drug pharmacokinetics do not account for the different drug response of the studied SCLC lines, presumably reflecting a different extent of DNA break formation and/or a different cytotoxic consequence of DNA damage.
Estrogen‐ and androgen‐responsive growth of human ovarian adenocarcinoma heterotransplanted into nude mice
Authors: Sawada Masumi , Terada Nobuyuki , Wada Akira , Mori Yoichi , Yamasaki Masato , Saga Tsuneo , Endo Keigo
Published: February 2007

A new line of human serous cystadenocarcinoma of the ovary, designated OVA‐5, has been established in athymic nude mice. A strong correlation was noted between tumor volume and plasma CA 125 levels in mice bearing OVA‐5 tumor. Growth of the OVA‐5 tumor in castrated male nude mice was accelerated by s.c. administration of estradiol‐17β and 5α‐dihydrotestosterone but not by progesterone. Estradiol‐17β and 5α‐dihydrotestosterone also accelerated the growth of the OVA‐5 tumor heterotransplanted into sialoadenectomized castrated male nude mice. No remarkable change was observed in the histological appearances of the tumors between control groups and hormone‐treated groups. Receptor assays revealed that the OVA‐5 tumor had both estrogen and androgen receptors. Growth of the OVA‐5 tumor is thus responsive to estrogen and androgen.
Importance of interferon α in the resistance of allogeneic C57B1/6 mice to the multiplication of friend erythroleukemia cells in the liver
Authors: Gresser Ion , Maury Chantal , Bandu Marie‐Thérèse , Belardelli Filippo
Published: February 2007

Friend erythroleukemia cells (FLC) (H‐2d) injected intravenously multiply extensively in the livers of syngeneic DBA/2 mice and not at all in the livers of allogeneic C57B1/6 mice. Our results indicate that interferon α (IFN‐α) is an important factor in the resistance of allogeneic mice to the multiplication of FLC in the liver. (a) After i.v. inoculation of FLC there was an inverse correlation between the presence of IFN‐α in the serum and the capacity of FLC to multiply in the liver. Thus, all 44 FLC‐injected adult C57B1/6 mice had circulating IFN‐α and FLC did not multiply in the liver of any of the mice. Interferon was not detected in the serum of 83% of 41 FLCinjected DBA/2 mice (and was found only at a low titer in 17% of the mice) and FLC multiplied in the liver of all mice. (b) FLC did multiply in the livers of newborn C57B1/6 mice and in the livers of irradiated adult C57B1/6 mice, and IFN‐α was not detected in their sera. In contrast, after i.v. inoculation of FLC, IFN‐α was detected in the sera of 3‐week‐old and athymic nu/nu adult C57B1/6 mice while FLC failed to multiply in the liver. (c) FLC also induced IFN‐α in congenic B10.D2 (H‐2d) mice and FLC did not multiply in the liver. We suggest that, depending on the site of tumor implantation, different host mechanisms have various degrees of importance in controlling the growth and/or rejection of allogeneic tumor cells, and that IFN‐α is particularly important when FLC are injected i.v.
Anthropometric variables and risk of breast cancer
Authors: Parazzini Fabio , Lavecchia Carlo , Negri Eva , Bruzzi Paolo , Palli Domenico , Boyle Peter
Published: February 2007

The role of anthropometric variables in the risk of breast cancer has been investigated using pooled data from 2 hospital‐based case‐control studies conducted in Italy for a total data‐set of 3,247 cases and 3,263 controls. No association was observed in pre‐menopausal women between breast cancer risk and height, weight, indices of body mass (W/H2; W/H1.5) and surface area. In post‐menopausal women, the risk of breast cancer was inversely related to height, being 0.8 in taller women (>165 cm) compared with women 155 cm tall or less; the trend in risk, although not constantly decreasing, was statistically significant (ptrend = 0.03). A direct, statistically significant association emerged with weight and indices of body mass and post‐menopausal breast cancer risk. Considering 2 indices of body weight (W/H2 and W/H1.5) and relative to thinner women, the respective estimated risks of post‐menopausal breast cancer increased to 1.4 and 1.3 for grossly obese women, and the corresponding p values for trend were respectively 0.002 and 0.02. The role of overweight was more evident in women with early age at menopause, thus suggesting a duration‐risk effect.
Metallothionein gene expression and resistance to cisplatin in human ovarian cancer
Authors: Schilder R. J. , Hall L. , Monks A. , Handel L. M. , Fornace A. J. , Ozols R. F. , Fojo A. T. , Hamilton T. C.
Published: February 2007

Intracellular thiols have been proposed as mediators of resistance to alkylating agents and cisplatin. As metallothionein is the predominant protein thiol, we examined its relationship to cisplatin resistance in human ovarian cancer cell lines. A human ovarian carcinoma cell line, A2780, derived from an untreated patient, was treated with cisplatin in several ways and the induced resistance to cisplatin ranged from 13‐ to 68‐fold. The degree of resistance was dependent upon the method of selection. The drug‐resistant cell lines also developed low levels of cross‐resistance to cadmium. Additional cell lines established from untreated patients or ovarian cancer patients refractory to cisplatin‐ and/or carboplatin‐containing combination chemotherapy were studied. The most cisplatin‐resistant cell lines, OVCAR‐8 and ‐10, were from patients previously treated with intensive chemotherapy. OVCAR‐8 was relatively cross‐resistant to cadmium while OVCAR‐10 appeared relatively sensitive. Cell lines were examined for expression of metallothionein mRNA to evaluate the relationship between cisplatin resistance, cadmium cross‐resistance and metallothionein expression. Only two of the cell lines with in vitro‐induced resistance to cisplatin, 2780E80 and 2780CP70B3, had detectable metallothionein mRNA. The other cell lines selected in vitro for cisplatin resistance, as well as the parental A2780 ovarian cancer cell line, showed no expression at our level of detection. There was variable expression of metallothionein among the OVCAR cell lines. Cell lines from untreated patients, OVCAR‐5 and ‐7, did express metallothionein, while the most cisplatin‐resistant cell lines, OVCAR‐8 and ‐10, did nat. We also examined cisplatin induction of metallothionein mRNA in the cell lines. Only 2780CP70B3 among the cell lines with in vitro‐induced cisplatin resistance showed increased expression after short‐term exposure to cisplatin. OVCAR‐4 also had a slight increase in expression after exposure to cisplatin. Mouse C127 cells transfected with a bovine papilloma virus‐metallothionein gene construct were compared for cisplatin sensitivity to the same cell type transfected with bovine papilloma virus alone. In this model system, metallothionein expression did not influence cisplatin cytotoxicity. On the basis of these studies, we conclude that there is no causal relationship between metallothionein expression and cisplatin resistance.
The locus of the polymorphic epithelial mucin (PEM) tumour antigen on chromosome 1q21 shows a high frequency of alteration in primary human breast tumours
Authors: Gendler Sandra J. , Cohen Edward P. , Craston Ann , Duhig Trevor , Johnstone Gillian , Barnes Diana
Published: February 2007

Tumour and blood leukocyte DNAs from sporadic breast cancer patients were examined for chromosome 1 loss of heterozygosity using a probe for a polymorphic epithelial mucin, PEM, which is expressed in >92% of breast carcinomas as well as in normal lactating breast tissue. Expression is detected by the monoclonal antibodies (MAbs) HMFG‐1,‐2 and SM‐3 which react with epitopes in the 20 amino‐acid repeat unit of the core protein. The PEM probe has been mapped to the chromosome band 1q21, a region that is often incriminated in chromosomal rearrangements in breast tumours. Loss of heterozygosity or alteration at the PEM locus was detected in 34% of the 70 informative patients examined. Twenty of the 24 individuals showed loss of an allele, whereas 4 showed gain of an additional allele or amplification of an existing allele. Twenty‐eight percent of informative cases exhibited alterations at the MS32 locus, 1q42–43, and 20% had alterations at the short arm locus MSI at 1p33–35. These findings identify the long arm of chromosome 1 and in particular the region around the PEM gene for localization of a gene whose loss or alteration may, in some tumours, contribute to the progression of disease in breast cancer patients.
Detection and isolation of antigen‐specific immune complexes from sera of melanoma patients
Authors: Wong Jan H. , Xu Shihong , Saxton Romaine E. , Gupta Rishab K. , Morton Donald L.
Published: February 2007

Detection of antigen‐specific circulating immune complexes (IC) in sera from cancer patients provides an approach for defining tumor antigens that induce a host immune response and could prove useful for purposes of immunoprognosis. In the present study, a sandwich ELISA was developed to detect antigen‐specific IC in cancer patients, utilizing a murine monoclonal antibody designated MAb JSI. The MAb was produced by cell fusion using standard hybridoma technology following immunization with a partially purified fetal antigen that had been isolated from the spent culture medium of a melanoma cell line. The partially purified antigen appeared to be broadly expressed on melanomas, sarcomas, and carcinomas. The MAb was mass‐produced in pristine‐primed mice. MAb JSI reacted with the cultured melanoma cell M14 but not the autologous lymphoblastoid cell L14. Following purification by ammonium sulfate precipitation, the MAb was immobilized on polystyrene plates and utilized to capture antigen‐specific immune complexes from sera of melanoma patients which were detected with anti‐human globulins. The second antibody in the sandwich was shown to be endogenous human IgG. Antigen‐specific immune complexes were present in melanoma patients but only infrequently in sera from normal individuals and patients with active autoimmune disease. Antigen‐specific immune complexes detected in melanoma sera were isolated by affinity chromatography utilizing the MAb JSI. The assay described in this report is simple and reproducible, without plate effect (p = 0.97) or time effect (p = 0.34) and could provide a useful new approach to examine the role of antigen‐specific circulating immune complex analysis in cancer patients.
Simultaneous monitoring of P53 protein and dna content of colorectal adenocarcinomas by flow cytometry
Authors: Remvikos Y. , Laurent‐Puig P. , Salmon R. J. , Frelat G. , Dutrillaux B. , Thomas G.
Published: February 2007

The p53 transformation‐related gene is located on 17p, a chromosomal segment frequently under‐represented in colorectal adenocarcinoma karyotypes. We have developed a flow cytometric method for detection of its gene product on isolated nuclei by indirect immunofluorescence. Criteria for defining the presence of p53 were established, using parameters related to the difference of fluorescence obtained by incubating nuclei with a specific monoclonal antibody (MAB) versus isotypic control. This method allowed simultaneous quantitation of p53 and DNA in tumor nuclei to be made. Twenty‐two of the 41 tumors analyzed (54%) were found to overexpress p53 when compared to 13 normal mucosa specimens. Repeated preparations from different fragments of the same tumor gave reproducible results for the 21 cases tested. p53 was detected in a higher proportion of disseminated tumors (64%) compared to localized disease (39%), but the difference did not reach statistical significance (X2 = 2.4, p > 0.10). Tumors containing aneuploid cell subpopulations were also more frequently positive (65%) than diploid ones (20%), the difference being significant (Fisher's exact test, p < 0.03). This dual parameter flow cytometric method, evaluating both DNA ploidy and p53 expression, may prove useful in identifying different biological subgroups of colorectal cancer.
Transcriptional down‐regulation of the rearranged c‐myc expression in murine cell hybrids between a plasmacytoma and a T‐cell lymphoma
Authors: Oikawa Tsuneyuki , Kondoh Nobuo , Fujita Hisakazu , Satoh Chiharu , Li Song Zhi , Yoshida Michihiro C. , Imamura Masahiro , Onoé Kazunori , Kuzumaki Noboru
Published: February 2007

Regulation of the rearranged and non‐rearranged c‐myc expression was studied in murine cell hybrids (SBWI and SBWII) between plasmacytoma (S194) and T‐cell lymphoma (BWS147) cells. Expression of the rearranged c‐myc of heterogeneous mRNA sizes (1.8 ∼ 2.4 kb) was markedly down‐regulated in these hybrids regardiess of retention of the gene. On the other hand, expression of the non‐rearranged c‐myc (2.4 kb) was not significantly affected in these hybrids. Treatment of SBWI hybrid ceiis with cycloheximide enhanced the non‐rearranged c‐myc 2‐ to 4‐fold but did not release the down‐regulation of the rearranged c‐myc at all, suggesting that the down‐regulation of the rearranged c‐myc in the hybrid cells was mainly at a transcriptional rather than a post‐transcriptional level. This was supported by the results of nuclear run‐on assay: the high level of run‐on transcripts in S194 cells declined in SBWI hybrid cells comparable to the level in BW5147 cells. The rearranged c‐myc was hemi‐methylated in S194 cells and the pattern was the same in SBWI hybrid cells. Furthermore, down‐regulation of the rearranged c‐myc in the hybrid was also not restored by treatment with 5‐azacytidine (5‐AzaC), 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) or forskolin, suggesting no causative involvement of DNA methylation or protein phosphorylation in down‐regulation. Higher DNase I sensitivity of the rearranged c‐myc in S194 cells decreased to a similar extent to that of the non‐rearranged c‐myc after cell fusion with BW5147 cells. These results suggest that expression of the rearranged c‐myc is down‐regulated at the level of transcription in murine cell hybrids between a plasmacytoma and a T‐cell lymphoma, probably by changing chromatin configuration around the gene from the open to the closed state.
Heterogeneity of polyoma tumors in hamsters: Analysis of cytoskeletal proteins and viral gene expression
Authors: Combette J. M. , Sappino A. P. , Türler H.
Published: February 2007

Murine polyomavirus‐induced hamster tumors revealed an unexpected heterogeneity with respect to patterns of cytoskeletal proteins expressed in different visceral and subcutaneous tumors and with respect to viral gene expression early during tumor outgrowth. All tumors analyzed expressed vimentin. Desmin was found in all heart tumors, to variable degrees in kidney tumors and in trace amounts only in I out of 4 s.c. tumors. The α‐smooth‐muscle actin isoform was observed in heart tumors only and was restricted to structures that we interpret as being proliferating pericytes or proliferating smooth‐muscle cells of the media. in kidneys of infected newborn animals and before the appearance of macroscopic tumors, viral early mRNAs were transcribed from free viral genomes. In tumor tissue the size of the viral transcripts was altered, suggesting that they were transcribed from integrated viral DNA. Since in each tumor discrete bands of viral RNAs were detected, individual tumors arose presumably from single cells and one functional integration event. In contrast, in situ hybridizations of kidney tissue and tumors showed large quantitative differences in viral gene expression not only between different tumors but also between individual cells of the same tumor.
Enhancement of the antiproliferative activity of cis‐diamminedichloroplatinum(II) by quercetin
Authors: Hofmann Johann , Fiebig Heiner H. , Winterhalter Bernd R. , Berger Dietmar P. , Grunicke Hans
Published: February 2007

We have shown previously that the flavonoid quercetin (3,3′,4′,5,7‐pentahydroxyflavone) enhances the antiproliferative activity of cis‐diamminedichloroplatinum(II) (cis‐DDP) in vitro. In order to investigate whether this observation could be exploited in cancer treatment, we tested this drug combination in human tumor xenografts. The established human large‐cell cancer of the lung (LXFL 529) was implanted s.c. into nude mice. Tumors were allowed to grow to a mean diameter of approximately 5 mm and the animals were subsequently treated intraperitoneally with quercetin, cis‐DDP or a combination of both. Treatment was given 3 times at 3‐day intervals. Twenty milligrams quercetin per kg body weight caused no inhibition in tumor growth compared to untreated controls; 3 mg cis‐DDP per kg body weight with the same time schedule reduced tumor growth, compared to quercetin‐treated and control animals. Concomitant treatment with 20 mg quercetin and 3 mg cis‐DDP per kg body weight reduced tumor growth to a significantly greater degree than cis‐DDP alone. Toxicity of this treatment was relatively low as determined by measurements of the body weight of the mice. A combination of 4 mg or 5 mg cis‐DDP with 20 mg quercetin per kg body weight also reduced tumor growth compared to single cis‐DDP treatment. The toxicity of treatment with these increased doses was high, as shown by the high lethality and the loss of body weight of surviving animals.
Cessation of autonomous proliferation of mouse lymphoma EL4 by fusion with a T cell line
Authors: Kubota Koichi , Katoh Hideki
Published: February 2007

Benzanthracene‐induced C57BL/6 (H‐2b) mouse T‐cell lymphoma EL4 (a thymidine kinase‐deficient cell line) was fused by using polyethylene glycol with an Mlsa (Mls for minor lymphocyte stimulatory) antigen‐dependent T cell line, which was designated G4 and had been derived from a C3H/He mouse (H‐2k), and the fused cells were cultured in HAT medium. Although no growing cells appeared in most of these fusions, we consistently obtained growth‐arrested H‐2Kb‐positive cells from the fused cell populations by the panning method. The cells were tetraploid and were able to proliferate in response to Mlsa antigen. Three H‐2Kb‐positive clones, isolated by limiting dilution from three different fusions, were shown to be EL4 × G4 hybrids, because (I) they had both H‐2k and H‐2b antigens; (2) each of the clones had one submetacentric chromosome which was a marker chromosome of EL4, and they were tetraploid with modal chromosome numbers of 74, 78, and 79, respectively; (3) they had 4 isozymes of both parental cells. These results indicate that EL4 lymphoma cells cease to proliferate when fused with T cell line G4. The malignant phenotype of lymphoma EL4 is thus suppressed at the level of cell transformation by the introduction of the G4 cell genome.
N‐myc gene is amplified in alveolar rhabdomyosarcomas (RMS) but not in embryonal RMS
Authors: Dias P. , Kumar P. , Marsden H. B. , Gattamaneni H. R. , Heighway J. , Kumar S.
Published: February 2007

DNA from 13 (6 alveolar and 7 embryonal) childhood rhabdomyosarcomas (RMS) was examined to determine the incidence and prognostic relevance of N‐ and c‐myc genes. Southern analysis showed 5‐ to 20‐fold amplification of N‐myc gene in 4 of 6 alveolar but in none of 7 embryonal RMS (p < 0.04; Fisher's exact test). The number of children who died with multiple‐ and single‐copy N‐myc gene was 4/4 and 5/9 respectively (p > 0.05; Chi‐squared test). There was no statistically significant correlation between N‐myc amplification and age, gender, site, stage or survival time. There was no amplification or gross rearrangement of c‐myc in any of the 13 RMS.
General primer‐mediated polymerase chain reaction permits the detection of sequenced and still unsequenced human papillomavirus genotypes in cervical scrapes and carcinomas
Authors: Van Den Brule Adriaan J. C. , Snijders Peter J. F. , Gordijn Roel L. J. , Bleker Otto P. , Meijer Chris J. L. M. , Walboomers Jan M. M.
Published: February 2007

A newly developed general primer‐mediated polymerase chain reaction (GP‐PCR) was used for the detection of a broad spectrum of Human Papilloma‐virus (HPV) genotypes, including unsequenced types, in cytologically normal and abnormal cervical smears and in biopsies of cervical carcinomas. This PCR method used different general primer sets, located in strongly conserved E1 and L1 regions of the HPV genome. Comparison between results of GP‐PCR and HPV‐type‐specific PCR (TS‐PCR) revealed an increase in overall HPV prevalence to 25%, 80% and 88% in scrapes with normally, slightly and severely dysplastic cells, respectively. Unsequenced HPV types were detected in 11% of cytologically normal swabs and in up to 30% of scrapes with dysplastic cells. Further characterization showed that unsequenced types concern HPV 13, 30, 31, 45, 51 and some other, possibly unknown HPV types. More than 90% of carcinomas in situ and invasive cervical carcinomas contained HPV. In the latter, only HPV16 and HPV18 were present. HPV16 was most frequently found in both normal and dysplastic cells, the rate being highest in neoplastic tissue. These results indicate that GP‐PCR is a powerful approach for detecting as yet uncharacterized HPV types associated with neoplastic transformation of cervical squamous cell epithelium.
Expression of the gene coding for human prostate‐specific antigen and related hGK‐1 in benign and malignant tumors of the human prostate
Authors: Henttu P. , Lukkarinen O. , Vihko P.
Published: February 2007

Human glandular kallikrein‐1 gene (hGK‐1) is closely related to the gene of human prostate‐specific antigen (PSA) and both genes are expressed in the human prostate. We have studied PSA and hGK‐1 mRNAs in human prostatic tissue samples from patients with benign prostatic hyperplasia (BPH) or adenocarcinoma (CA), using Northern and slot‐blot analysis in order to gain insight into the expression of these highly similar genes. Multiple mRNAs were found to originate from both genes. The major mRNA species of 1.6 kb accounted for 57% to 76% of the total coding capacity for PSA in different tissue specimens, but a variant mRNA species of 1.9 kb was also abundant. Most of the BPH samples contained marked amounts of an aberrant 0.9 kb mRNA, and long PSA mRNAs of 6.1 kb, 4.5 kb and 3.1 kb were found in elevated amounts in some of the CA samples. The amount of PSA mRNAs that would produce aberrant PSA proteins if translated into protein varied from 18% to 38% in these tissue samples. The major mRNA species originating from hGK‐1 was of 1.6 kb, but other less abundant mRNA species could also be observed. The amount of PSA and hGK‐1 mRNAs was determined from slot blots hybridized with specific oligonucleotide probes. No significant differences could be found in the PSA gene expression between BPH and CA samples. The total amount of the PSA mRNAs in all the different BPH specimens was fairly similar, but there was a 3‐fold difference between the highest and lowest PSA mRNA levels in the CA samples. The hGK‐1 mRNA levels in the BPH specimens studied demonstrated greater variance than the PSA mRNA levels in the same samples. The correlation between PSA gene and hGK‐1 expression in the BPH samples was good, suggesting that there are similarities in the regulation of these genes. However, the lack of correlation between the amounts of PSA and hGK‐1 mRNAs in the CA samples except in sample CI indicates that there are also differences in the gene regulation. The observed 3.7‐ to 6.5‐fold excess of PSA mRNAs as compared with the amount of hGK‐1 mRNAs present in the same tissue specimen also indicated differences in the cis‐ or trans‐acting regulatory elements of these genes.
O‐linked mucin‐type glycoproteins in normal and malignant colon mucosa: Lack of T‐antigen expression and accumulation of tn and sialosyl‐Tn antigens in carcinomas
Authors: Ørntoft Torben F. , Harving Niels , Langkilde Niels C.
Published: February 2007

The expression of carbohydrate core‐structures on O‐linked glycoproteins was examined in fetal (n = 6), infantile (n = 2), normal adult (n = 15), and malignant (n = 22) colorectal tissue by means of monoclonal antibodies (MAbs) specific for Tn (Ga1NAcα1‐O‐R), sialosyl‐Tn (NeuAcα2‐6Ga1NAcα1‐O‐R), and T (Ga1β‐3GalNAcα1‐O‐R) antigens. Immunolabelling of solubilized malignant tissue, separated by SDS‐PAGE, showed expression of Tn and sialosyl‐Tn antigens on 3 molecules of similar mw (230, 210, and 170 kDa), whereas no T antigens could be detected. Immunohistochemical techniques showed that fetal colon mucosa expressed Tn antigens but no sialosyl‐Tn antigens. Infantile colon mucosa, however, expressed Tn as well as sialosyl‐Tn antigens, and normal adult colon mucosa cells expressed no Tn antigens but sialosyl‐Tn in 2 out of 6 biopsies from cecum, which indicates occurrence post partum of α‐6‐NeuAc‐transferase. Endothelium in normal adult mucosa showed expression of both Tn and sialosyl‐Tn antigens; 82% of carcinoma tissue sections expressed Tn antigens, and 73% expressed sialosyl‐Tn antigens in mucin or cytoplasm, or on luminal cell membranes. T antigens could be detected neither in normal mucosa cells at any stage of development, nor in carcinomas. The possibility exists that this could be due to masking of T antigen. Mucin‐type blood‐group A antigens which contain an internal T‐disaccharide were demonstrated in 4 out of 4 A1 tumors by means of MAb HH5. However, urea‐containing SDS‐PAGE analysis demonstrated an HH5 binding to molecules different from those binding anti‐Tn. In remote morphologically normal and abnormal crypts in colons from carcinoma patients, both Tn and sialosyl‐Tn antigens were expressed in secreted mucin in 40% of the cases. The data indicate an expression of O‐linked Tn and sialosyl‐Tn core structures in fetal and infantile colon and in colorectal carcinomas.
Detection of somatic mutations in tumours of diverse types by DNA fingerprinting with M13 phage DNA
Authors: Hayward Nicholas , Chen Philip , Nancarrow Derek , Kearsley John , Smith Peter , Kidson Chev , Ellem Kay
Published: February 2007

Hybridization of M13 phage DNA to Southern blots of human DNA produces an individual‐specific DNA fingerprint. In this study, tumour and lymphocyte DNA from a series of patients with melanoma, Merkel‐cell carcinoma, Burkitt's lymphoma and Wilms' tumour was probed with M13 DNA to detect somatic mutations in the DNA of the tumours. Somatic changes were observed in tumour DNA of 16 out of the 28 cases examined. This frequency compared favourably with the frequency with which tumour‐specific changes have been found when using the Jeffreys DNA fingerprinting probe 33.15, and demonstrates that M13 DNA provides a useful additional probe for the study of somatic changes in tumours. The finding that multiple DNA fragments were lost or gained in DNA fingerprints from individual tumours indicates a marked degree of complexity in the genetic changes involved in the evolution of certain human cancers.
Plantar melanoma: Is the incidence of melanoma of the sole of the foot really higher in blacks than whites?
Authors: Stevens Nancy G. , Liff Jonathan M. , Weiss Noel S.
Published: February 2007

The overall incidence of malignant melanoma in black populations is considerably lower than that in whites. There have been repeated suggestions in the literature that black persons may have an increased incidence of melanoma of the sole, relative to whites, because among blacks with melanoma there is a high proportion with tumors of the sole of the foot. Whether this observed difference in site distribution represents a difference in incidence rates has never been demonstrated. Data on cancer incidence from 2 areas, western Washington State (1974–1983) and metropolitan Atlanta (1975–1984), were analyzed to examine this question. The annual area‐ and age‐adjusted incidence of plantar melanoma was 1.7 per million per year for blacks and 2.0 per million per year for whites (relative risk for blacks as compared with whites = 0.88, 95% confidence interval = 0.36–2.11). These data argue that in North America there is little difference between blacks and whites in the incidence of plantar melanoma, and that the well known proportional difference appears to be due instead to the decreased incidence in blacks of melanoma on skin surfaces other than the soles of the feet.
Hormone and cytotoxic drug responsiveness of cultured human breast cancer cells resistant to specific hormones
Authors: Coldham N. G. , Patel K. , Braunsberg H.
Published: February 2007

Attempts have been made to develop sublines of MCF‐7 cells resistant to the growth‐inhibitory actions of medroxyprogesterone acetate (MPA), dexamethazone (DEX), antioestrogens or high‐dose oestradiol (E2) by prolonged exposure to high hormone concentrations. While high degrees of resistance to MPA, DEX and E2 were achieved, cells remained anti‐oestrogen‐sensitive after prolonged treatment with 4 μM tamoxifen (TAM) or the anti‐oestrogen LY 117018 (LY), Cells resistant to DEX were also resistant to MPA, while cells resistant to high‐dose E2 remained sensitive to TAM. Cells resistant to MPA and E2 appeared to be less responsive to cytotoxic drugs than wild‐type cells, while resistance to DEX was associated with increased sensitivity. The responses of tumours to cytotoxic drugs may be affected by prior endocrine therapy.
Exacerbation of doxorubicin cardiotoxicity by digoxin administration in an experimental rabbit model
Authors: Reeves William C. , Griffith James W. , Wood Mary Ann , Whitesell Lawrence
Published: February 2007

The relationship between digoxin administration and the development of doxorubicin cardiomyopathy was evaluated in a chronic experimental rabbit model. We graded the myocardial pathology by conventional light microscopic histologic techniques. Additionally, myocardial fibrosis was quantified by hydroxyproline determinations and myocardial cellular damage by technetium‐99m pyrophosphate uptake. Twenty‐four rabbits were studied: 6 control, 6 doxorubicin‐treated, and 12 digoxin‐doxorubicin‐treated. Mortality in the digoxin‐doxorubicin group was 50%. All other rabbits lived throughout the entire experiment. The severest grades of histologic lesions were seen only in the digoxin‐doxorubicin group. Myocardial hydroxyproline content was greater (p < 0.05) in the digoxin‐doxorubicin group than in the doxorubicin or control groups. Myocardial technetium‐99m pyro‐phosphate content was also significantly greater (p < 0.05) in the digoxin‐doxorubicin group than in controls. In conclusion, the pretreatment and continued administration of digoxin, together with doxorubicin, increased the severity of myocardial damage and reduced longevity in this experimental model of doxorubicin cardiotoxicity.
Immune surveillance: Both CD3+ CD4+ and CD3+ CD8+ T cells control in vivo growth of P815 mastocytoma
Authors: Flamand Véronique , Biernaux Cécile , Van Mechelen Marcelle , Sornasse Thierry , Urbain Jacques , Leo Oberdan , Moser Muriel
Published: February 2007

The aim of this study was to examine whether a spontaneous immune response controls neoplastic growth in P815‐bearing DBA/2 mice, and to characterize the cells involved in tumor resistance in vivo. Several cell lineages such as T‐cell‐receptor (TcR)‐bearing T cells, NK cells and macrophages mediate some anti‐tumor activity in vitro. P815 was chosen as a model because it is weakly immunogenic and is a good target both for tumor‐specific, MHC‐restricted CTL‐mediated lysis and for MHC‐unrestricted lysis exerted by long‐term cultured lymphocytes or activated macrophages. Since most “NK‐like activity” in freshly isolated populations appears to be associated with CD3− cells, whereas antigen‐specific, MHC‐restricted T cells mostly express CD3 determinants, CD3 was a good marker for evaluating the role of T cells and “NK” cells in tumor resistance in vivo. The survival of anti‐CD3‐treated animals that were inoculated with tumor cells was strongly reduced (mean survival time: 17 days vs. 40 days for the control group) and was associated with increased tumor growth rate. We followed the same approach to define the T‐cell subset(s) that mediate(s) this immune response. Both CD4+ and CD8+ T cells were required for induction of immune control on neoplastic growth. The approach used has revealed the important role of CD4+ T cells in immune responses that control in vivo growth of a class‐1‐positive, class‐II‐negative tumor and suggests that these cells may play a central role in tumor resistance. Since CD4+ cells are activated by soluble, exogenous proteins, this finding may have important implications for immunotherapy.
Risk of pancreatic cancer in relation to medical history and the use of tobacco, alcohol and coffee
Authors: Farrow D. C. , Davis S.
Published: February 2007

A population‐based case‐control study was conducted to examine the relationship between certain medical conditions, the use of tobacco, alcohol and coffee, and the incidence of pancreatic cancer. Cases (N = 148) were married men ages 20 through 74 years diagnosed with pancreatic cancer from July 1982 through June 1986. Controls (N = 188) were identified by random digit dialing. Wives, responding as surrogates for both cases and controls, were interviewed by telephone and completed, alone, a food frequency questionnaire. The risk of pancreatic cancer was increased in individuals with a history of diabetes or pancreatitis, and decreased in those with a history of tonsillectomy. Individuals who had ever smoked cigarettes were at elevated risk of disease. This excess risk was confined to current smokers, in whom the odds ratio was 3.2 (95% CI 1.8‐5.7); the risk among former smokers resembled that in those who had never smoked. There was no excess risk of pancreatic cancer among those who had ever used other forms of tobacco, including pipe tobacco, cigars and chewing tobacco. After adjustment for demographic and dietary characteristics, there was no association between pancreatic cancer risk and the intake of coffee, beer, red wine, hard liquor or all alcohol combined; a slight reduction in risk was seen among those consuming white wine daily.
Association of oral contraceptive use and human papillomaviruses in invasive cervical cancers
Authors: Hildesheim Allan , Reeves William C. , Brinton Louise A. , Lavery Carol , Brenes Maria , De La Guardia Maria Elena , Godoy Julio , Rawls William E.
Published: February 2007

In a study of 197 cases of histologically confirmed invasive cervical cancer, 61% of biopsies were positive for human papillomavirus (HPV) DNA by Southern or dot‐blot hybridization. An association between detection of HPV DNA and oral contraceptive use was observed when HPV‐positive and ‐negative cases were compared. Women reporting recent or longterm (>4 yrs) oral contraceptive use were at 2.3 and 2.9‐fold increased risks of HPV positivity, respectively. An increased risk of HPV positivity was also associated with formal education and with urban residence, while long‐term smoking was negatively associated with HPV detection. A non‐significant trend of increasing risk of HPV positivity with increasing number of sexual partners of the women and of the male partners of monogamous women was observed. Detection of HPV DNA was not associated with other cervical cancer risk factors examined, including age at first coitus, number of pregnancies, and Pap smear screening history. Our findings suggest either an interaction between HPV infection and oral contraceptive use in the genesis of cervical cancer or an increased expression of HPV genome in neoplasms of oral contraceptive users. These observations also support a multifactorial model of cervical cancer causation.
Detection of a soluble form of the CD30 antigen in sera of patients with lymphoma, adult T‐cell leukemia and infectious mononucleosis
Authors: Pfreundschuh M. , Pohl C. , Berenbeck C. , Schroeder J. , Jung W. , Schmits R. , Tschiersch A. , Diehl V. , Gause A.
Published: February 2007

Using a sandwich enzyme‐linked immunosorbent assay (ELISA) we were able to detect a soluble form of the CD30 antigen (CD30s) in the supernatant of cell lines expressing membrane‐bound CD30 and in T and B cells after transformation with human T‐cell leukemia virus (HTLV‐1) and Epstein‐Barr‐Virus (EBV). While CD30s was not found in 250 healthy controls, it was detected in the sera of patients with Hodgkin's disease (23/100), anaplastic large‐cell (6/9), angioimmunoblastic (2/2) and one unclassified high‐grade non‐Hodgkin's lymphoma (NHL), as well as in 18/20 patients with acute adult T‐cell leukemia (ATL, HTLV‐1‐positive). It was absent in a large number of patients with other high‐grade NHL, all low‐grade NHLs, acute or chronic leukemias and solid tumors. The only non‐malignant disease with detectable levels of CD30s was infectious mononucleosis (9/10). The membrane‐bound form of CD30 has a molecular weight of 120 kDa. Western blot analysis revealed that CD30s in the serum of patients has a molecular weight of 88 kDa, identical to the antigen released by cell lines in vitro. CD30s disappeared in all originally positive cases after successful treatment and reappeared in relapsing patients. Thus, CD30s may be useful as a specific marker for disease activity of certain types of lymphoma and ATL.
Transcription of biliary glycoprotein I gene in malignant and non‐malignant human liver tissues
Authors: Hinoda Yuji , Imai Kohzoh , Nakagawa Naoaki , Ibayashi Yumiko , Nakano Tatsumi , Paxton Raymond J. , Shively John E. , Yachi Akira
Published: February 2007

Biliary glycoprotein I (BGP I) is a member of carcinoembryonic antigen (CEA) gene family consisting of at least II related genes. The transcription of BGP I gene was analysed in malignant and non‐malignant human liver tissues with a 396‐bp 3′‐untranslated region probe from a cDNA clone 4‐13 which was newly isolated from an adult human colon cDNA library. Among 21 tissue samples from 14 patients with hepatocellular carcinoma, 16 samples were clearly shown to express a single 3.9‐kb message. This message was also found in the hepatoma cell line HuH‐7. When the malignant tissues were compared to the non‐malignant ones for the intensity of the band, no significant difference was observed. mRNAs of CEA and non‐specific cross‐reacting antigen (NCA) were not detected in 5 samples which were shown to have the message of the BGP I gene. These data suggest that the human hepatocyte and its malignant transformant produce BGP I, and that this could correspond to the cross‐reacting antigen previously detected in the liver.