bluuebunny/crossref_metadata_2025 huggingface dataset:
Human peri‐tumoral and lung fibroblasts produce paracrine motility factors for recently established human sarcoma cell strains
Authors: Hu Mei , Pollock Raphael E. , Nakamura Toshikazu , Nicqlson Garth L.
Published: February 2007

Paracrine motogenic cytokines secreted by normal cells can stimulate metastatic cell invasion. For example, human fibroblasts secrete hepatocyte growth factor/scatter factor (HGF/ SF), which stimulates paracrine migration of epithelial and certain carcinoma cells, and migration‐stimulating factor (MSF), which stimulates autocrine migration of fibroblasts from certain breast carcinomas. We found that human peri‐tumoral and lung fibroblasts secrete motility‐stimulating activity for several recently established human sarcoma cell strains. Motility of lung metastasis‐derived SYN‐I sarcoma cells was preferentially stimulated by human lung and peri‐tumoral fibroblast motility‐stimulating factors (FMSFs). FMSFs were non‐dialyzable, susceptible to trypsin and sensitive to dIthiothreitol. Cycloheximide inhibited accumulation of FMSF activity in conditioned medium; however, addition of cycloheximide to the migration assay did not significantly affect motility‐stimulating activity. Purified HGF/SF, rabbit anti‐hHGF and RT‐PCR analysis of peri‐tumoral and lung fibroblast HGF/SF mRNA expression indicated that FMSF activity was unrelated to HGF/SF. Partial purification of FMSF by gel exclusion chromatography revealed several peaks of activity, suggesting multiple FMSF molecules or complexes. Since human soft tissue sarcomas have a distinctive hematogenous metastatic pattern (predominantly lung), FMSF may play a role in this process independent of HGF/SF. © 1995 Wiley‐Liss, Inc.
Characterization of a 95 kilodalton membrane glycoprotein associated with multi‐drug resistance
Authors: Doyle L. Austin , Gao Yongming , Yang Weidong , Ross Douglas D.
Published: February 2007

Over‐expression of a 95‐kDa membrane protein (P‐95) has been reported previously in the multi‐drug‐resistant (MDR) breast cancer cell line MCF‐7/AdrVp and the MDR small cell lung cancer line NC1‐H1688. We have now developed anti‐sera against gel‐purified P‐95 protein from each of these cell lines. Western blotting with each serum demonstrates a broad band at 95‐kDa with detergent‐solubilized membrane proteins from MCF‐7/AdrVp and NC1‐H1688 cells, which is barely detectable in membrane proteins from drug‐sensitive parental MCF‐7 cells. Each anti‐serum cross‐reacts with a 190‐kDa membrane protein (P‐190) in NC1‐H1688 but not MCF‐7/AdrVp cells. Immunoblotting and silver staining of NC1‐H 1688 membrane proteins separated by two‐dimensional gel electrophoresis demonstrates that P‐95 and P‐190 run as broad streaks with low iso‐electric points. Incubation of NC1‐H 1686 cells with tunicamycin or cleavage of carbohydrate residues of NCI‐H 1688 or MCF‐7/AdrVp membrane proteins with PNGase F leads to the appearance of a sharp 35‐kDa band reactive with anti‐P‐95 antisera. This 35‐kDa protein has been isolated by two‐dimensional gel electrophoresis. Neuraminidase digestion converts P‐95 to a broad 65‐kDa immunoreactive band, indicating the presence of terminal sialic acid residues. In conclusion, P‐95 is an N‐linked sialoglycoprotein with a 35‐kDa polypeptide core. © 1995 Wiley‐Liss, Inc.
Local delivery of the topoisomerase I inhibitor camptothecin sodium prolongs survival in the rat intracranial 9L gliosarcoma model
Authors: Weingart Jon D. , Thompson Reid C. , Tyler Betty , Colvin O. Michael , Brem Henry
Published: February 2007

Camptothecin, a naturally occurring inhibitor of the DNA‐replicating enzyme topoisomerase I, demonstrated promising anti‐tumor activity in pre‐clinical testing; however, because of unexpected toxicity and low anti‐tumor effects in the initial clinical trials, further testing was discontinued. We hypothesized that local controlled delivery of camptothecin sodium would achieve effective concentrations in brain tumors without the observed systemic side effects, thereby allowing this novel drug to be used to treat patients with malignant gliomas. To test this hypothesis, we evaluated the sensitivity of rat glioma lines and established human glioma lines to camptothecin in vitro. We found that the LD90 for the established rat and human lines was 0.3 to 1.4 μM after a 1 hr exposure and decreased to less than O.1 μM after continuous exposure for 7 days. We loaded camptothecin into a controlled‐release polymer (ethylene‐vinyl acetate co‐polymer; EVAc) and showed by high‐pressure liquid chromatography that controlled release occurred over at least 21 days. We then tested camptothecin against 9L gliosarcoma, implanted into the brain of Fischer 344 rats. Five days after tumor implantation, animals were treated with camptothecin delivered either systemically or locally by release from EVAc. Local controlled delivery by the polymer significantly extended survival: 59% of the treated animals were long‐term survivors (> 120 days) compared to 0% of controls. Systemic administration did not extend survival compared to controls. We compared the efficacy of camptothecin delivered locally with a polymer to camptothecin injected directly into the tumor. Camptothecin increased survival only when delivered locally by polymer. © 1995 Wiley‐Liss, Inc.
Suppression of human melanoma cell growth and metastasis by the melanoma‐associated antigen CD63 (ME491)
Authors: Radford Kristen J. , Mallesch Julia , Mersey Peter
Published: February 2007

CD63 has been identified in human melanoma cells by a number of different monoclonal antibodies (MAbs). Studies with MAbs have shown that expression is most marked in naevi and early forms of cutaneous melanoma and reduced in vertical growth phase and metastatic lesions. To investigate further the role of CD63 in progression of melanoma, genomic CD63 was transfected into a CD63‐negative human melanoma cell line using an episomal vector. The stable transfected melanoma cells had similar growth rates to control transfected melanoma cells in vitro but much lower growth rates when injected intradermally into athymic nude mice. The CD63‐transfected cells also had a reduced number of metastases in the peritoneal cavity and subcutaneous sites when injected intravenously. MAb against CD63 did not influence the growth of CO63‐transfected melanoma cells in vitro. Our results confirm previous studies using H‐ros‐transformed NIH3T3 fibroblasts and suggest that CD63 may have a role as a tumor suppressor gene in human melanoma that acts to limit invasion and progression of melanoma. © 1995 Wiley‐Liss, Inc.
Role of a small molecular weight phosphoprotein in the mechanism of action of CI‐994 (N‐acetyldinaline)
Authors: Rummel Sue A. , Kraker Alan J. , Steinkampf Randall W. , Hook Kenneth E. , Klohs Wayne D.
Published: February 2007

The mechanism of action of the novel anti‐cancer compound CI‐994 was studied in C26 murine colon tumor and HCT‐8 human colon adenocarcinoma cells. Treatment of either cell line resulted in the specific loss of a 16‐kDa phosphoprotein in a time‐ and concentration‐dependent manner. Treatment with salicylanilide, C1–940, mimosine, aphidicolin, quercetin or ciclo‐ pirolxalamine, which, like C1–994, block cells in the G,‐S phase of the cell cycle, did not affect the production of this protein. Loss of the 16‐kDa protein preceded the block in cell proliferation induced by C1–994 treatment, and recovery of this protein was evident prior to the resumption of cell growth. Cellular fractionation studies demonstrated that the 16 kDa phosphoprotein is confined to the nuclear compartment. Our data indicate that loss the 16‐kDa nuclear phosphoprotein appears to be a direct effect of C1–994 treatment and that the inhibition of this phosphoprotein may play a critical role in the mechanism of action of C1–994. © 1995 Wiley‐Liss, Inc.
Epidermal growth factor expression in human colon and colon carcinomas: Anti‐sense epidermal growth factor receptor rna down‐regulates the proliferation of human colon cancer cells
Authors: Rajagopal Sriram , Huang Shuang , Moskal Thomas L. , Lee Bang‐Ning , El‐Naggar Adel K. , Chakrabarty Subhas
Published: February 2007

Human colon cancer cell lines express epidermal growth factor (EGF) mRNA, secrete EGF and may respond to it via the cell‐surface EGF receptor (EGFR). Expression of these molecules in human colon and colon tumor, however, is not clear. Reverse transcription‐polymerase chain reaction (RT‐PCR) analyses of RNA prepared from paired normal human colon and colon tumor samples from 12 individuals followed by Southern blotting analyses of the RT‐PCR products revealed a major fragment of 527 bp and a minor fragment of 404 bp that hybridized to a human EGF cDNA probe under stringent conditions. Identical results were obtained from 8 human colon cancer cell lines. Cloning and sequencing of PCR products confirmed that both fragments were from the human EGF gene; the 527‐bp fragment corresponded exactly to nucleotides 2,891 to 3,417 of the human EGF mRNA reported by others. A deletion of 123 nucleotides (nucleotides 3,172 to 3,294) was found in the 404‐bp fragment. Immunohistochemical studies using cryostat sections of human colon specimens showed that EGF was expressed in the human colon and that expression was restricted to the epithelial colonic crypt cells and epithelium‐ derived cancer cells. Since EGF and EGF‐related molecules are potent mitogens that mediated their effect through the EGFR, we also determined the efficacy of anti‐sense EGFR RNA in circumventing the EGFR‐related pathway of proliferation. Expression of anti‐sense EGFR RNA, by transfection with an inducible anti‐sense EGFR expression vector, down‐regulated cell‐surface EGFR expression and proliferation of these cells and their ability to grow in soft agar. Anti‐sense EGFR RNA was found to be an anti‐proliferative agent in both relatively non‐ aggressive and highly aggressive human colon cancer cells. © 1995 Wiley‐Liss, Inc.
Characterization of a prostate carcinoma mucin‐like antigen (PMA)
Authors: Beckett Mary Lou , Wright George L.
Published: February 2007

A recently identified, high m.w. human tumor antigen, reactive with monoclonal antibody (MAb) PD41 and designated prostate mucin antigen (PMA), was found to have expression highly restricted to prostate carcinomas. Both biochemical and immunological characteristics of this antigen and its relationship to other tumor‐associated mucins and various species of submaxillary mucins were evaluated. Immunohistochemical examination of submaxillary tissues revealed differential expression of this antigen and other human tumor‐associated mucins, with MAb PD41 expression found only in bovine submaxillary gland serous cells. Neuraminidase treatment enhanced antibody binding by 50%, suggesting partial masking of the PD41 epitope by sialic acid. Antigenicity was reduced by treatment with alkaline‐borohydride, sodium metaperiodate, β‐galactosidase, O‐glycanase, and various proteolytic enzymes. MAb PD41 antibody binding also could be significantly reduced by selected lectins and sugars suggesting that the immunodominant carbohydrate involved in the epitope was an O‐linked oligosaccharide containing N‐acetyl galactosamine as a major component. This antigen was further distinguished from T, Tn, or Sialyl‐Tn antigens and blood group carbohydrate antigens by radioimmunometric analyses. Cross‐blocking and double determinant RIA experiments also showed a distinction between the PD41 epitope and several well‐characterized tumor‐associated mucin antigens such as MUCI, CEA, M344, OCI25, and AR3 as well as bovine submaxillary core protein. Our results indicate that the PD41‐reactive epitope is a non‐acidic O‐linked carbohydrate or glycopeptide epitope with restricted expression in prostate carcinomas and bovine submaxillary glands. This expression is distinct from other mucin‐like tumor‐associated antigens identified in human prostate carcinomas. © 1995 Wiley‐Liss, Inc.
Growth control of human colon‐adenocarcinoma‐derived Caco‐2 cells by vitamin‐D compounds and extracellular calcium in vitro: relation to c‐myc‐oncogene and vitamin‐D‐receptor expression
Authors: Hulla Wolfgang , Kállay Enikö , Krugluger Walter , Peterlik Meinrad , Cross Heide S.
Published: February 2007

The human colon‐cancer cell line Caco‐2, though of malignant origin, is still able to express the c‐myc proto‐oncogene in a regulable fashion. Transition from the logarithmic growth phase into the quiescent, i.e., confluent state, is accompanied by a significant increase in the number of cells in the G0/G1 phase of the cell cycle and a concomitant reduction of c‐myc mRNA and of nuclear association of c‐myc protein. Conversely, growth stimulation by lowering extracellular [Ca++]0 to 0.25 mM results in up‐regulation of c‐myc expression levels and consequently inhibition of re‐entry of Caco‐2 cells into the G0/G1 phase. In contrast, regulation of c‐myc in Caco‐2 cells is completely resistant to vitamin‐D sterols, since the anti‐mitogenic action of 1α,25‐dihdroxyvitamin D3 (1α,25(OH)2D3) and of 2 synthetic analogs, 1α,25(OH)2–16‐ene‐23‐yne‐D3 and 1α,25(OH)2–26,27‐F6–16‐ene‐23‐yne‐D3, occured independently of any change in c‐myc mRNA and nuclear protein levels. Although the anti‐proliferative effect of the vitamin‐D sterols requires high‐affinity binding to the cytoplasmic vitamin‐D receptor (VDR), vitamin‐D sterols have no effect on VDR mRNA levels in Caco‐2 cells. However, VDR mRNA expression changed in an anti‐parallel fashion to c‐myc regulation upon transition between different growth states. This suggests that VDR mRNA abundance could nevertheless be important for vitamin‐D‐related c‐myc‐independent growth control in Caco‐2 cells. © 1995 Wiley‐Liss, Inc.
DNA‐binding properties of novel cis‐ and trans platinum‐based anticancer agents in 2 human ovarian carcinoma cell lines
Authors: Mellish Kirste J. , Barnard Christopher F. J. , Murrer Barry A. , Kelland Lloyd R.
Published: February 2007

We have investigated the comparative initial DNA binding properties of 7 platinum‐based anticancer drugs: 5 cis‐oriented compounds, cisplatin, tetraplatin (Ormaplatin), JM118 [cis ammine dichloro (cyclohexylamine) platinum (II)], JM216 [bis‐acetato cis ammine dichloro (cyclohexylamine) platinum (IV)] and JM149 [cis ammine dichloro (cyclohexylamine) trans dihydroxo platinum (IV)], and 2 trans‐oriented compounds, transplatin and JM335 [trans ammine dichloro (cyclohexylamine) dihydroxo platinum (IV)] in SKOV‐3 and CH1 human ovarian carcinoma cells. Unlike transplatin, the trans complex JM335 was comparably cytotoxic to its cis isomer JM149 and cisplatin. No significant correlation was observed between levels of total platinum bound to DNA after exposure to the 7 drugs and cytotoxicity in either cell line. Using a competitive enzyme‐linked immunoabsorbent assay, DNA extracted from CM1 cells exposed to the 5 cis platinum drugs was recognized by the monoclonal antibody ICR4 (raised against DNA platinated by cisplatin) in the order JM118 > cisplatin > JM216 > tetraplatin > JM149; a strong positive correlation which just attained statistical significance was observed between recognition by ICR4 and cytotoxicity. In contrast, DNA extracted from CH1 cells exposed to the trans platinum drugs transplatin and JM335 was no more immunoreactive than control DNA. Using alkaline elution, interstrand cross‐link levels after exposure to drug did not correlate with cytotoxicity in either cell line. The 5 cis drugs formed interstrand cross‐links in both cell lines, whereas transplatin formed very low levels in SKOV‐3 and undetectable levels in CH1. JM335 was efficient at forming interstrand cross‐links in SKOV‐3 but, notably, none were observed in CH1. In contrast, in the CH1 cells, single‐strand breaks were observed with JM335 (but not with any other drug). The novel trans complex JM335 was unique, among the platinum drugs studied, in its ability to form both DNA interstrand cross‐links and single strand breaks (DNA lesion formation being cell line dependent), a property which may account for its cytotoxicity. © 1995 Wiley‐Liss, Inc.
Elevation of aldose reductase gene expression in rat primary hepatoma and hepatoma cell lines: Implication in detoxification of cytotoxic aldehydes
Authors: Takahashi Motoko , Funjii Junichi , Miyoshi Eiji , Hoshi Ayumu , Taniguchi Naoyuki
Published: February 2007

Aldose reductase and aldehyde reductase are members of the aldo‐keto reductase super‐family, and participate in the reduction of a wide range of carbonyl compounds. We have purified aldose reductase from rat lens and raised antiserum against it in rabbits. Immunoblot analyses using this antibody showed that a significant amount of aldose reductase was expressed in cell lines derived from hepatomas while it was negligible in normal hepatocytes. Elevated expression of aldose reductase was also observed in cancerous lesions of 3′‐methyl‐4‐dimethyl‐aminoazobenzene (3′‐Me‐DAB)‐induced hepatocarcinomas. Expression of aldose reductase mRNA was confirmed in these cells by Northern‐blot analysis, suggesting that the induction occurred at the stage of gene transcription. The level of aldehyde reductase, however, did not change in cancerous tissue or in the cell lines. The viability of hepatoma cells in the presence of 3‐deoxyglucosone and glyceraldehyde was decreased by an aldose reductase inhibitor, ONO‐2235 (5‐[(1Z,2E)‐2‐methyl‐3‐phenylpropenylidene]‐4‐oxo‐2‐thioxo‐3‐thiazolidin‐eacetic acid). Taken together, induction of aldose reductase gene expression during hepatocarcinogenesis may render cancer cells resistant to various toxic carbonyl compounds produced during metabolism or administered as anti‐cancer drugs. © 1995 Wiley‐Liss, Inc.
Migratory patterns of lac‐z transfected human glioma cells in the rat brain
Authors: Pedersen Paal‐Henning , Eovardsen Klaus , Garcia‐Cabrera Inmaculada , Mahesparan Rupavathana , Thorsen Jon , Mathisen Berit , Rosenblum Mark L. , Bjerkvig Rolf
Published: February 2007

Malignant brain tumors are characterized by extensive tumor‐cell infiltration into the normal brain tissue. The present work describes the migratory behavior of human glioma cells transplanted into the adult rat brain with the aim of exploiting the extent of active cell migration and passive cell displacement within the central nervous system. To detect every transplanted tumor cell, a stably bacterial β‐galactosidase (loc‐z) transfected human glioma cell line was used. To distinguish between an active cell migration process and passive cell displacement, rat brains were also implanted with inert fluorescent polystyrene microspheres and the distribution of tumor cells and micro‐ spheres was studied 1 hr and 3 days after implantation. One hour after implantation the tumor cells were strictly localized at the implantation site. However, 3 days after implantation, both tumor cells and microspheres showed an extensive distribution within the brain. Confirming earlier neuropathological and experimental studies, it is shown that the loc‐z‐transfected glioma cells had the capacity to move within the Virchow‐Robin and subarachnoid spaces. However, since fluorescent micro‐spheres were also found in these areas, this spread of tumor cells may be primarily mediated by the extensive cerebrospinal fluid flow that exists within the brain. Three days after implantation, the glioma cells also showed an active migration over the corpus callosum. In comparison, the fluorescent microspheres showed only limited spread along the callosal body. It is concluded that the bacterial lac‐z gene can be stably transfected into human glioma cells and, since every tumor cell can be visualized within the brain, this model provides a tool for studying the mechanisms behind tumor‐cell invasion of the brain. © 1995 Wiley‐Liss, Inc.
Bladder tumours following chemotherapy and radiotherapy for ovarian cancer: A case—control study
Authors: Kaldor John M. , Day Nicholas E. , Kittelmann Berndt , Pettersson Folke , Langmark Froydis , Pedersen Dorthe , Prior Patricia , Neal Frank , Karjalainen Sakari , Bell Janine , Choi Won , Koch Maria , Band Pierre , Pompe‐Kirn Vera , Garton Catherine , Staneczek Wolfhardt , Zarén Birgitta , Stovall Marilyn , Boffetta Paolo
Published: February 2007

A collaborative group of cancer registries and hospitals carried out a case—control study of tumours of the bladder in women who had previously been treated for ovarian cancer. A total of 63 cases of bladder tumours were identified, and 188 controls were selected matching for age, year of ovarian cancer diagnosis and survival time. Full details of the treatment for ovarian cancer were sought both for cases and for controls. The risk of bladder tumours was increased for patients who had been treated by radiotherapy alone (1.9; 95% confidence interval, 0.77–4.9), by chemotherapy alone (3.2; 0.97–10), and by chemotherapy and radiotherapy (5.2; 1.6–16), when comparison was made with patients treated only by surgery. Patients treated by chemotherapy were separated into 2 groups according to whether they had received cyclophosphamide. Among those who had, there was a clear increase in risk (approximately 4‐fold) regardless of whether or not they had also received radiotherapy. For those who received only other drugs, risk was increased substantially among patients who had also been treated by radiation, as compared with patients treated by surgery alone, and those who had received radiotherapy only. Both melphalan and thiotepa were implicated as potential bladder carcinogens on the basis of these results. The estimated risk of bladder tumours due to cyclophosphamide was more than twice the risk following radiation to the bladder, and it appeared substantially earlier. For both agents, the risk continued to increase more than 10 years after treatment began.
An ecological study of diet and lung cancer in the South Pacific
Authors: Le Marchand Loïc , Hankin Jean H. , Bach François , Kolonel Laurence N. , Wilkens Lynne R. , Stacewicz‐Sapuntzakis Maria , Bowen Phyllis E. , Beecher Gary R. , Laudon François , Baqué Pierre , Daniel Roro , Seruvatu Laijia , Henderson Brian E.
Published: February 2007

Incidence rates of lung cancer have been markedly lower for Fiji than for other South Pacific countries, despite similar rates of smoking. We conducted population‐based surveys in several island nations of the South Pacific (Cook Islands, Fiji, Tahiti and New Caledonia) and used data from Caucasian, Japanese, Hawaiian, Filipino and Chinese controls in a case‐control study of lung cancer in Hawaii to investigate the role of diet in explaining differences in lung cancer incidence among 20 ethnic‐sex groups. In a stepwise linear regression of lung cancer rates on smoking, diet and other variables, smoking, as expected, explained the majority (61%) of the variability in incidence. However, several dietary components also explained significant portions of the variance. Lutein intake explained 14% and vitamin E intake, cholesterol intake and height explained 5–7% each of the remaining variance in incidence. Associations with lutein and vitamin E were inverse, whereas those with cholesterol and height were direct. Dietary β‐carotene intake was not associated with lung cancer incidence. These ecological data provide evidence for a protective effect of lutein against lung cancer. A protective effect of dietary vitamin E and a risk‐enhancing effect of dietary cholesterol are also suggested.
Effectiveness of screening for breast cancer in women under 50 years at entry: The Kotka pilot project in Finland
Authors: Hakama Matti , Pukkala Eero , Kallio Mervi , Godenhjelm Kari , Svinhufvud Ulla
Published: February 2007

It is still uncertain whether mammography is beneficial to women under 50 years of age. We report a follow‐up of 4 I ‐year birth cohorts in 13 Finnish municipalities subjected to service screening. The women in these cohorts were born in even calendar years and they were 40–47 years old at the time of first screening, which was repeated every other year. At the beginning, 4, 163 women were invited and 86% attended. Women were screened with mammography, physical breast examination and information on detection and early diagnosis of breast cancer by breast self‐examination (BSE) was given. Incident cases of breast cancer and breast‐cancer deaths were recorded. The expected numbers of incident breast‐cancer cases and deaths from breast cancer were derived from control women who were residents of the same municipalities but who were born in adjacent calendar years (odd years) to those screened. In the screened cohorts 13 cancers were screen‐detected, 32 cancers were interval cases and 8 cases were diagnosed among the non‐attenders, while in the controls 85 cancers were detected during a 9‐year follow‐up from 1982 to 1990. One death from breast cancer occurred in the screened cohorts among cases diagnosed between 1982 and 1990, against 10 expected breast‐cancer deaths during a 10‐year follow‐up from 1982 to 1991 of women initially free of breast cancer. Breast‐cancer mortality in the screened cohorts was significantly lower than in the controls (Rate Ratio 0.11), but it is not clear how much of the reduction in mortality could be accounted for by the mammography itself and how much to other activities included in the screening programme (especially training in BSE) or to chance variation. It is unlikely that a programme sensitivity of 25% (13/53) would have resulted in 89% (100‐11) effectiveness or reduction in the risk of death from breast cancer.
Clonal heterogeneity in breast cancer: Karyotypic comparisons of multiple intra—and extra—tumorous samples from 3 patients
Authors: Teixeira Manuel R. , Pandis Nikos , Bardi Georgia , Andersen Johan A. , Mitelman Felix , Heim Sverre
Published: February 2007

Intratumor phenotypic heterogeneity is one of the characteristics of breast carcinomas, and genetic mechanisms are likely to contribute to it. We have studied breast cancer clonal heterogeneity by cytogenetic analysis of multiple tumor samples (one from each tumor quadrant) as well as samples of macroscopi‐cally normal surrounding breast tissue from 3 patients with this disease. Clonal chromosome aberrations were found in all 8 successfully analyzed samples from the carcinomas. Two to 6 cytogenetically unrelated clones were detected in each case, unevenly distributed among the tumor quadrants. Karyotypic abnormalities were also found in 4 out of 9 macroscopically tumor‐free samples from the surrounding tissue; in 2 of these samples, a ductal carcinoma in situ was detected histologically, and the cytogenetic evidence suggests that the remaining 2 samples also contained neoplastic cells. Quantitative analysis of the findings revealed a statistically significant higher frequency of karyotypically abnormal cells in samples with a histologic diagnosis of carcinoma vs. samples without any detected malignancy. That cells bearing cytogenetic evidence that they belong to the tumor parenchyma are left behind during breast‐conserving surgery for carcinoma of the breast may account for the relatively high long‐term local relapse rates seen in this disease.
Effect of gastrointestinal hormones and synthetic analogues on the growth of pancreatic cancer
Authors: Robertson John F. R. , Watson Susan A. , Hardcastle Jack D.
Published: February 2007

The effects of hormones and synthetic analogues have been examined on the growth of 2 human pancreatic cancer cell lines, MiaPaCa2 a well‐established cell line and PAN I which was derived in our own laboratories from a tumour specimen. The hormones/growth factors included gastrin (G‐17), epidermal growth factor (EGF) and bombesin, while the synthetic analogues used were a gastrin receptor antagonist (CR 1718), a somatostatin analogue (RC‐160) and a bombesin receptor antagonist (ICI 216, 140). Cell proliferation was assessed by the [75Se]selenomethionine uptake method which has been shown to correlate with cell counts. The effect of each hormone or growth factor on growth was expressed as a percentage of the untreated control. There were 5 replicates in each experiment, and each one was repeated at least 3 times. In vitro growth of both cell lines was unaffected by gastrin, bombesin or the respective antagonists (CR 1718 and ICI 216140). The somatostatin analogue RC‐160 also had no effect on basal growth. Significant growth stimulation of both MiaPaCa2 and PANI was seen with epidermal growth factor. We tested the hypothesis that somatostatin analogues may inhibit EGF‐stimulated growth on both MiaPaCa2, a somatostatin receptor positive cell line, and on PANI which is negative for somatostatin receptors. RC‐160 did not inhibit EGF‐stimulated growth of either Mia‐PaCA2 or PANI. Both cell lines were established in vivo as xenografts in nude mice. The effect of RC‐160 on tumour growth was measured. RC‐160 inhibited the growth of Mia‐PaCa2, the somatostatin receptor‐positive cell line, but not of PANI.
Human chromosome 11 suppresses the tumorigenicity of adenovirus transformed baby rat kidney cells: Involvement of the wilms' tumor 1 gene
Authors: Menke A. L. , Van Ham R. C. A. , Sonneveld E. , Shvarts A. , Stanbridge E. J. , Miyagawa K. , Van Der Eb A. J. , Jochemsen A. G.
Published: February 2007

Human chromosome 11 was introduced into adenovirus‐transformed baby rat kidney (BRK) cells by microcell‐mediated chromosome transfer. The resulting microcell hybrids (MCHs) showed a reduced ability to form tumors upon s.c. injection into athymic mice. Further analysis, with the use of defined deletion chromosomes of lip, indicated that the presence of region 11 p 13‐p 12 is necessary for the suppression of tumorigenicity. In contrast, the presence of region lip 15–14.1 appeared to increase the rate of tumor growth. Expression studies on the human Wilms' tumor I (WTI) and the insulin‐like growth factor II (IGF‐II) genes, which lie in regions 11 p 13 and 11 p 15, respectively, suggested the involvement of both genes in determining the degree of suppression of tumorigenicity. Finally, stable expression of a murine WTI protein in the adenovirus‐transformed cells resulted in almost complete suppression of tumorigenicity, establishing the WTI protein as a tumor suppressor in this cell system.
Loss of cell‐contact regulation and altered responses to autocrine motility factor correlate with increased malignancy in prostate cancer cells
Authors: Silletti Steve , Yao Ji Ping , Pienta Kenneth J. , Raz Avraham
Published: February 2007

Tumor cell migration and proliferation in new organ environments are critical steps in cancer progression and can be modulated by tumor‐ and host‐secreted molecules. Autocrine motility factor (AMF) is a tumor‐secreted cytokine which regulates growth and motility by a receptor‐mediated pathway. The AMF receptor, a 78‐kDa cell surface glycoprotein (gp78), is regulated by cell contact in normal fibroblastic and bladder cells; however, this mechanism is disrupted during tumor progression. A prostatic carcinoma cell line which is low‐ to non‐metastatic in nude mice (PC‐3) and a derived metastatic variant (PC‐3M) were examined to determine if gp78 cell density regulation is involved in prostate cancer progression. Both cell lines expressed gp78 and, although the basal migration of the parental PC‐3 cells was higher than that of the metastatic variant, only the PC‐3M cells were capable of responding to tumor‐derived AMF with increased motility. Furthermore, these cells exhibited differential patterns of wound closure in an experimental system whereby the low‐metastatic PC‐3 cells migrated primarily along the wound edge while individual high‐metastatic PC‐3M cells entered the cell‐free wound area directly. Cell surface gp78 distribution distinguished the cell populations with a markedly concentrated display of gp78 in polarized capped regions on the surface of the metastatic cells. Cell‐cell contact down‐regulated gp78 expression in the parental, but not the metastatic, cells, and mitogenic responses to exogenous AMF differed between these cell lines as well. In this model, metastasis appears to be associated with aberrant regulation of gp78 expression and distribution, coupled with enhanced exploitation of AMF's locomotory and prolifera‐tive effects.
Ultraviolet‐B‐light‐induced mutagenesis of C‐H‐ras codons 11 and 12 in human skin fibroblasts
Authors: Amstad Paul A. , Cerutti Peter A.
Published: February 2007

Mutations in the ras oncogene are detected with a high frequency in non‐melanoma skin cancer. Approximately half of the squamous‐cell carcinomas (SCC) and one third of the basal‐cell carcinomas (BCC) carry mutations at the second position of Ha‐ras codon 12 (GGC to GTC), whereas mutations in Ki‐ras codon 12 occur less frequently. Since the mutations in the Ha‐ras and Ki‐ras oncogenes are located opposite potential pyrimidine dimer sites (C‐C), it is likely that the mutations are induced by ultraviolet radiation present in sunlight. We studied the capacity of ultraviolet B (UVB) light to induce base‐pair changes in Ha‐ras codons 11 and 12 in human skin fibroblasts. UVB induced mostly C to T and G to A transitions and C to A and G to T transversions. The base‐pair change with the highest relative abundance was C to T in the middle position of codon 11 followed by (in diminishing relative abundance) C to A in the middle position of codon 11, G to A and G to T in the middle position of codon 12. The C to T and G to A transitions are compatible with pyrimidine photodimers as pre‐mutagenic lesions, whereas the C to A and G to T transversions could be generated due to the formation of 8‐hydroxyguanine, which is the major oxidation product of guanine. The relative abundance of mutations induced by UVB in Ha‐ras codons 11 and 12 does not correlate with mutations observed in the DNA from non‐melanoma skin cancer, where the G to T transversion in the middle position of codon 12 is selected.
Malignant transformation of human fibroblast strain MSU‐1.1 by v‐fes requires an additional genetic change
Authors: Lin Chiencheng , Maher Veronica M. , McCormick J. Justin
Published: February 2007

To determine whether the v‐fes oncogenc can malignantly transform human fibroblasts that have acquired an infinite life span and are partially growth‐factor‐independent, we trans‐fected cell strain MSU‐1.1 with a plasmid containing the v‐fes oncogene and a bacterial histidinol dehydrogenase gene. Of the 60 independent histidinol‐resistant clones isolated and assayed for v‐fes expression using a fes‐specific monoclonal antibody, 6 were found to express the v‐fes protein at a detectable level. When progeny cells from these 6 clones were further characterized, 3 of the 6 clonal populations exhibited a significant increase in the ability to form medium‐sized colonies in agarose, but none were tumorigenic in athymic mice. However, when the 6 populations were propagated for many generations, the same 3 populations acquired the ability to form very large colonies in agarose (± 100 μm in diameter) at a frequency of 2% to 17%, and formed malignant tumors in athymic mice. This suggests that an additional genetic change required for malignant transformation had been spontaneously acquired in 3 of the v‐fes ‐transformed cell strains. To determine whether the change or changes were the equivalent of an activated sis or ras proto‐oncogene, we transfected the v‐fes oncogene into derivative strains of MSU‐1.1 that express a transfected v‐sis, c‐H‐ras or c‐N‐ras oncogene, but that do not form tumors, and assayed the v‐fes‐expressing transfectants for tumorlgenicity. The results showed that when complemented either by a ras oncogene expressed at a somewhat enhanced level or by the v‐sis oncogene, v‐fes can supply the additional change required for malignant transformation.
Loh and mutation analysis of CDKN2 in primary human ovarian cancers
Authors: Campbell Ian G. , Beynon Gareth , Davis Michael , Englefield Pat
Published: February 2007

The CDKN2 gene encodes a cell cycle regulatory protein and is located on chromosome 9p21, a region deleted in a wide variety of primary tumours. While mutations in the CDKN2 gene itself are frequently observed in tumour cell lines, they are less common in primary tumours. We have investigated the role of the CDKN2 gene in ovarian cancer by analysis for allelic loss of 9p21 and single‐strand conformational polymorphism analysis of exons 1 and 2 of CDKN2 in 67 primary ovarian tumours. Loss of heterozygosity on 9p21 was frequently observed (24/50 informative tumours) and was common in early‐stage tumours, suggesting that it is an early event in ovarian tumorigenesis. Homozygous deletion of the CDKN2 gene was detected in only 1 tumour. No somatic or germline mutations were observed in CDKN2, though a codon 140 polymorphism was detected in 2 cases. This suggests that CDKN2 is not involved in ovarian tumorigenesis and that another gene(s) may be the target of the frequent 9p allelic losses observed.
CDKN2 in HPV‐positive and HPV‐negative cervical‐carcinoma cell lines
Authors: Kelley Michael J. , Otterson Gregory A. , Kaye Frederic J. , Popescu Nicholas C. , Johnson Bruce E. , Dipaolo Joseph A.
Published: February 2007

Human cervical cancers frequently contain retinoblastoma protein (Rb) that is inactivated by binding with human papilloma virus (HPV) E7 protein or through mutation. The CDKN2 gene encodes p 16INK4 which inhibits cdk4‐cyclin D phosphorylation of Rb, preventing the G1‐S transition. To determine whether abnormalities of CDKN2 occur in cervical‐cancer cells, 11 cervical cell lines, including 8 HPV‐positive cell lines, 2 HPV‐negative cell lines containing mutant Rb, and one tumorigenic cell line derived from normal cervical cells following transfection with HPV‐16 and v‐H‐ras (CX16‐2HR), were analyzed. No cell line had a homozygous deletion of exon 1 or 2 of CDKN2, and only one cell line, CX16‐2HR, had an altered DNA sequence, which represents a common polymorphism at codon 148. To exclude the possibility of other subtle inactivating mutations, immunoblot analysis of protein lysates was performed using a polyclonal anti‐p 16INK4 rabbit anti‐serum. Abundant levels of normal‐sized pl6INK4 were observed in all cell samples. Thus, no alterations of CDKN2 were detected in these cervical cell lines. These results confirm that mutational inactivation of p 16INK4 is a rare event in tumor samples with compromised Rb activity.
Development of new ricin A‐chain immunotoxins with potent anti‐tumor effects against human hodgkin cells in vitro and disseminated Hodgkin tumors in scid mice using high‐affinity monoclonal antibodies directed against the CD30 antigen
Authors: Schneix Roland , Linnartz Christoph , Katouzi Ali A. , Schon Gisela , Bohlen Heribert , Horn‐Lohrens Ottmar , Parwaresch Reza M. , Lange Hans , Diehl Volker , Lemke Hilmar , Engert Andreas
Published: February 2007

The lymphocyte activation marker CD30 has been shown to be an excellent target for the immunotherapy of human Hodgkin's lymphoma. In order to develop new potent immunotoxins (ITs) against CD30, we chemically linked 6 recently described monoclonal antibodies (MAbs) via SMPT to deglycosylated ricin A‐chain (dgA). Cross‐blocking experiments demonstrated that these MAbs, termed Ki‐2 to Ki‐7, recognize 3 different clusters on the CD30 antigen: Ki‐2, Ki‐4, Ki‐5 and Ki‐7 recognize cluster A; Ki‐6 recognizes cluster B; Ki‐3 binds to cluster C. Staining of 29 sections of normal human organs revealed no major cross‐reactivity of any MAbs tested. Binding to the CD30 antigen on LS40Cy Hodgkin cells was assessed by flow cytometry, and demonstrated high affinities for Ki‐2, Ki‐3 and Ki‐4. The concentration giving 50% of the mean fluorescence intensity (MFI50) was 0.58 μg/ml to 0.78 μg/ml. MAbs Ki‐5, Ki‐6, and Ki‐7 bound much more weakly. The staining intensity of the MAbs correlated with the cytotoxicity of the corresponding ITs. Ki‐2.dgA, Ki‐3.dgA and Ki‐4.dgA inhibited the protein synthesis of L540Cy cells by 50% at concentrations (IC50) of 3.5 × 10−l0 M to 4.0 × 10−11 M. The most effective IT, Ki‐4.dgA, is 5‐fold more potent than previously reported CD30 ricin A‐chain ITs. Ki‐4.dgA was subsequently used for the treatment of disseminated human Hodgkin's lymphoma in a SCID mouse model. The mean survival time (MST) of lymphoma‐bearing SCID mice was extended from 42 days in untreated controls to more than 132 days when Ki‐4.dgA was applied one day after tumor challenge. Ki‐4.dgA is a new potent IT suitable for further evaluation against Hodgkin's lymphoma in man.
Endogenous D‐factor activity partially mediates the toxic but not the therapeutic effects of tumor necrosis factor
Authors: Block Mark I. , Fraker Douglas L. , Strassmann Gideon , Billingsley Kevin G. , Arnold W. Scott , Perlis Cliff , Alexander H. Richard
Published: February 2007

We have earlier shown that passive immunization against differentiation‐inducing factor/leukemia‐inhibitory factor (D factor) activity improves the survival of endotoxemic mice, suggesting that D factor may contribute to the systemic toxicity associated with tumor necrosis factor (TNF). In the current experiments, TNF induced D‐factor gene expression in various tissues of non‐tumor‐bearing female C57B1/6 mice. Passive immunization against D‐factor significantly improved survival after a lethal TNF challenge in both non‐tumor‐bearing (p2 < 0.02) and tumor‐bearing mice (p2 < 0.01). In mice bearing 10‐days.c. MCA 105 sarcomas, D‐factor antibody alone had no effect on tumor growth as compared with control IgG. Tumor regression and regrowth in mice treated i.v. with TNF was not affected by pre‐treatment with D‐factor antibody, as compared with pre‐treatment with IgG. However, TNF‐treatment‐related mortality was abrogated by pre‐treatment with D‐factor antibody (0% vs. 36% for IgG‐pre‐treated controls). These results indicate that endogenous D‐factor activity contributes to the toxicity but not to the anti‐tumor effects of TNF therapy. With renewed interest in the use of TNF for the treatment of patients with cancer, improved understanding of the role of D factor in mediating the effects of TNF may have important clinical benefits.
Cell‐cycle‐dependent invasion in vitro by rat ascites hepatoma cells
Authors: Iwasaki Teruo , Shinkai Kiyoko , Mukai Mutsuko , Yoshioka Kiyoko , Fujii Yoshitaka , Nakahara Kazuya , Matsuda Hikaru , Akedo Hitoshi
Published: February 2007

The relationship between cell cycle and experimental metastasis of tumor cells in vivo has been investigated, but it remains to be elucidated which step of metastasis, or whether tumor‐cell invasion in particular, depends on cell cycle. We previously reported an in vitro cell‐monolayer invasion (transcellular migration) assay system, in which the invasive capacity of tumor cells is measured by counting tumor cells penetrating beneath a cultured mesothelial cell monolayer after tumor‐cell seeding. Using our invasion assay system, the relationship between invasive capacity and cell‐cycle distribution of MMI cells, a highly invasive clone of rat ascites hepatoma AH130, was investigated. Invasive capacity of aphidicolin‐ or hydroxyurea‐synchronized tumor cells enriched in G1/S—early S‐phase cells was about 2 to 6 times higher than that of asynchronous cells. According to time‐course experiments to examine the relationship between invasive capacity and the size of fraction of cells in each phase after release from an aphidicolin or a nocodazole block, it was suggested that MMI cells are most invasive in G1/S‐S phase. Phagokinetic assay using colloidal gold particles showed that one possible reason for the enhanced invasiveness might be the increased cell motility in such phases, as suggested by the in vitro invasion assay.
Cocktails of ricin a‐chain immunotoxins against different antigens on hodgkin and sternberg‐reed cells have superior anti‐tumor effects against H‐RS cells in vitro and solid Hodgkin tumors in mice
Authors: Engert Andreas , Gottstein Claudia , Bohlen Heribert , Winkler Ute , Schön Gisela , Manske Oliver , Schnell Roland , Diehl Volker , Thorpe Philip
Published: February 2007

Three ricin A‐chain immunotoxins (ITs) recognizing different antigens on Hodgkin‐Reed/Sternberg (H‐RS) cells were evaluated for their anti‐tumor effects when used in combination as “cocktails”. These ITs, BB10.dgA (CD2S), HRS3.dgA (CD30), and IRac.dgA (70 kDa), strongly inhibited the growth of L540Cy H‐RS cells in vitro. The protein synthesis of this cell line was reduced more efficiently by the combination of 2 of these ITs than by BB10.dgA, HRS3.dgA or IRac.dgA alone. A cocktail of all 3 ITs was most effective in vitro. This was at least in part due to the non‐homogeneous distribution of CD25, CD30 or IRac on the L540Cy H‐RS target cells and to the fact that sub‐populations deficient in one antigen nevertheless expressed appreciable levels of the other target antigens. IT cocktails were also superior as anti‐tumor agents in nude mice with solid L540Cy tumors. Ninety percent of mice treated with cocktails containing 2 or 3 ITs had continuous complete remissions (CCR), as compared with only 40% of mice treated with the same dose of a single IT. Analysis of 7 L540Cy sub‐lines re‐established ex vivo from mice that relapsed after having achieved complete remission (CR) after therapy with a single IT showed that the surviving tumor cells were antigen‐deficient variants which were resistant to the original IT, but which could be killed by ITs directed against other target antigens. Thus, IT cocktails give superior results against human H‐RS cells, both in vitro and in vivo.
Lung carcinoma and malignant mesothelioma in patients exposed to thorotrast: Incidence, histology and p53 status
Authors: Andersson Michael , Wallin Håkan , Jönsson Marzieh , Nielsen Lise L. , Visfeldt Jakob , Vyberg Mogens , Bennett William P. , De Benedetti Virna M. G. , Travis Lois B. , Storm Hans H.
Published: February 2007

In a previous registry‐based survey of 999 patients injected with α‐emitting 232ThO2 (Thorotrast), we identified elevated risks for lung carcinoma and malignant mesothelioma. Since injected Thorotrast is retained lifelong mostly in liver, spleen and lymph nodes, the mesothelial surfaces of these organs are constantly irradiated. Thorotrast‐administered patients also perpetually exhale 220Rn, a 232Th‐daughter. Study of Thorotrast‐exposed patients may, therefore, provide data with regard to carcinogenicity of radon exposure, a current public health concern, as well as the pathogenesis of malignant mesothelioma. The incidence and histologic types of lung carcinoma and malignant mesothelioma within the cohort were examined by review of available histopathologic material and medical records. Further, mutations of the p53 gene were analyzed whenever possible as it has previously been suggested that radon‐associated lung carcinomas exhibit specific mutational patterns. The cumulative risk for lung carcinoma reached 11.0% based on 20 confirmed cases. Nine were small cell lung cancer (SCLC), whereas the expected frequency was 18%. The risk for malignant mesothelioma reached 2.5% based on 7 cases. The actuarial risk of malignant mesothelioma for patients given more than 20 ml Thorotrast was 7.8% compared to 1.4% for patients administered smaller amounts. Seven lung carcinomas and 5 malignant mesotheliomas were analyzed for p53 mutations; only 1 (in a lung adenocarcinoma) was detected. A possible association between Thorotrast and SCLC is suggested. In addition, a possible dose‐response gradient exists for Thorotrast and malignant mesothelioma.
No preferential loss of one parental allele of chromosome 17p13.3 in childhood medulloblastoma
Authors: Scheurlen Wolfram G. , Krauss Jürgen , Kühl Joachim
Published: February 2007

Medulloblastomas are the most frequent malignant tumors of the central nervous system in childhood. Loss of heterozygosity of the telomeric part of chromosome 17p has been described frequently in these tumors, suggesting a possible second tumor‐suppressor gene in this region apart from the p53 gene. Using restriction‐fragment‐length polymorphism and microsatellite polymorphism analysis, we screened 16 medulloblastomas for 17p 13.3 deletions and compared the DNA patterns of patients' tumors and normal tissues with those of one or both parents. Loss of heterozygosity of chromosome 17p 13.3 could be detected in 6 out of 16 tumors (37.5%). In 4 of these 6 tumors the maternal allele was deleted, in 2 tumors the paternal allele. Although the number of tumors investigated is limited, we find no evidence that genomic imprinting of the chromosomal region most frequently deleted in medulloblastoma plays a role in tumorigenesis.