bluuebunny/crossref_metadata_2025_split huggingface dataset:
Allele‐specific detection of K‐ras oncogene expression in human non‐small‐cell lung carcinomas
Authors: Slebos Robert J. C. , Habets Gaston G. M. , Evers Siegina G. , Mooi Wolter J. , Rodenhuis Sjoerd 
Published: July 2010

AbstractPoint mutations in codon 12 of the K‐ras oncogene are frequent in human lung adenocarcinomas. To study the expression of the K‐ras gene in these tumors we have developed a mRNA detection technique based on the polymerase chain reaction (PCR). By this technique, K‐ras expression can be detected semi‐quantitatively in samples of less than 100 ng total RNA. Hybridization of the amplified cDNA sequences with mutation‐specific oligonucleotides allows separate quantification of the expression of normal and point‐mutated alleles in a single sample. RNA samples from 24 human non‐small‐cell lung carcinomas (NSCLC), from 2 lung metastases of colonic adenocarcinomas, from 3 human lung adenocarcinoma cell lines, and from normal lung tissue were analyzed. In most tumors, expression of K‐ras was detected at levels equal to or several times higher than those found in normal lung tissue. A lung metastasis from a colon adenocarcinoma, known to contain an amplified K‐ras gene, highly over‐expressed the K‐ras gene. In those tumors in which the K‐ras oncogene was activated by a point mutation, both alleles of the gene were expressed. Our results show that a high over‐expression of K‐ras is a rare event in human lung carcinomas, but that a certain degree of over‐expression of the mutated allele can be demonstrated in tumors with an activated K‐ras gene. With the technique we describe here, adequate estimation of the expression of specific genes in minimal amounts of tumor cells becomes possible.
Effects of steroids on laminin‐binding integrins in a human melanoma cell line
Authors: Lopes M. T. P. , Sonohara S. , Chammas R. , Brentani M. M. 
Published: July 2010

AbstractThe MEL‐85 human melanoma cell line was used to investigate the effects of both estradiol and dexamethasone on expression of laminin (LM) receptors and cell adhesion capacity. Immunoblotting of eluates from whole‐cell extracts applied to LM Sepharose indicates the presence of an LM‐binding protein of 116–130 kDa that reacted with an anti‐pi integrin antibody, suggesting that the putative LM receptor of MEL‐85 cells is a member of the integrin family. Analysis of l2Sl‐LM binding to whole cells indicates the existence of low‐affinity components which display positive co‐operativity. LM‐fragment‐8 competes for this binding to the same extent as unlabelled LM (75%), while fragment PI is inactive and fibronectin (FN) competes by about 30% only. Binding of labelled fragment‐8 exhibits a pattern similar to that of intact LM. Cell adhesion to substrates coated with LM and LM fragments closely parallels binding to cells in suspension. MEL‐85 cells were estradiol‐receptor‐negative. Estradiol treatment did not stimulate LM receptor levels or attachment to LM. Growth rate also remained unaltered. To characterize the glucocorticoid dependence of MEL‐85 cells, we first established the presence of glucocorticoid receptors and an inhibitory effect on growth rate. Dexamethasone treatment resulted in marked enhancement of adhesion to LM, without alterating LM receptor number or affinity. In addition, dexamethasone changed the morphology of MEL‐85 cells in conjunction with higher LM expression as evaluated by immunofluorescence.
Increased methotrexate‐induced DNA strand breaks and cytotoxicity following mutational loss of thymidine kinase
Authors: Sano Hirohiko , Kubota Masaru , Kasai Yasufumi , Hashimoto Hisako , Shimizu Tsunehiro , Adachi Souichi , Mikawa Haruki 
Published: July 2010

AbstractThe cytotoxicity and DNA lesions induced by methotrexate (MTX) were compared in wild‐type, hypoxanthine‐guanine phosphoribosyltransferase‐deficient (HGPRT) and thymi‐dine‐kinase‐deficient (TK) HL‐60 cells. TK‐ and HGPRT cells were approximately 10 and 3 times more sensitive to MTX than wild‐type cells, respectively. Following incubation with 2 m̈m MTX for 16 hr, TK‐ cells showed a significantly higher number of DNA strand breaks. Concomitantly, DNA fragmentation at the nucleosomal linker region was detected more prominently in TK‐ cells. Although MTX tended to decrease TTP pools similarly in all 3 cell types, the initial TTP level in TK‐ cells was only about one‐fifth of that found in the wild type. These results indicate that the thymidine salvage pathway has a pivotal role in mediating MTX‐induced toxicity and DNA lesions.
Therapeutic effectiveness against mopc—315 plasmacytoma of low or high doses of the synthetic thymic hormone THF—γ2 in combination with an “immunomodulating” or a “non—immunomodulating” drug
Authors: Ophir R. , Pecht M. , Burstein Y. , Harshemesh H. , Ben‐Efraim S. , Trainin N. 
Published: July 2010

AbstractWe reported previously that treatment of mice bearing MOPC—315 plasmacytoma with the drugs L—PAM (phenylalanine mustard) or S—FU (5—fluorouradl), in combination with low doses of THF—γ2, was more effective in increasing their survival time than treatment with the drug alone. We show here that in the combined treatment using a single injection of S—FU followed by multiple (8–15) injections of THF—γ2, the megadoses were more effective than the low doses in increasing the survival time of MOPC—315 tumor—bearing mice. On the other hand, in combination with L—PAM, both low and high doses of THF—γ2 were equally effective. The need for high doses of THF—γ2, when used in combination with 5—FU, could be due to the fact that 5—FU acts as a “non—immuno—modulating” drug and has to be used at a high, immunosuppressive dose.
The role of G‐protein in matrix‐mediated motility of highly and poorly invasive melanoma cells
Authors: Lester Bruce R. , Weinstein Lee S. , McCarthy James B. , Sun Zhengqi , Smith Ron S. , Furcht Leo T. 
Published: July 2010

AbstractMembranes from 2 K1735 murine melanoma clones of high invasive capacity show increased amounts of pertussis toxin (PT) substrate when compared to a weakly invasive cellular counterpart. Using a panel of specific G‐protein antibodies, we identified Giα2 as the PT‐sensitive G‐protein uniquely abundant in highly invasive cells. In addition, RNA hybridization results confirm the immunoblot observations that Giα2 is present at higher levels in strongly invasive cells. This result suggests that the elevated expression of Giα2 in highly invasive cells is not entirely due to differences in either translational efficiency or protein degradation but is related to altered RNA transcriptional initiation, processing and/or degradation. ADP‐ribosylation of G1 α‐subunits by PT inhibited the fi‐bronectin, laminin and collagen type‐IV‐stimulated motility of the 2 highly invasive clones, while PT treatment of cells from a poorly invasive clone resulted in little or no reduction of the fibronectin, laminin or collagen type‐IV‐stimulated lower motility. Furthermore, PT treatment of highly or poorly invasive KI735 clones does not result in any alteration in cellular cAMP accumulation, suggesting that the PT substrate is not linked with the adenylyl cyclase enzyme complex. The data suggest that a PT‐sensitive G‐protein, probably Giα2, regulates second messenger pathways that contribute to elevated motility in highly invasive KI735 cells.
Vascularity, perfusion rate and local tissue oxygenation of tumors derived from rus‐transformed fibroblasts
Authors: Kaixinowski F. , Wilkerson R. , Moore R. , Strauss W. , Vaupel P. 
Published: July 2010

AbstractTumors derived from ras‐transformed rat fibroblasts were investigated in order to gain insight into possible interrelationships between oncogenic transformations and therapeutically relevant parameters of the metabolic micromilieu of solid tumors in vivo. Tumors grew in nude mice after injection of in vitro‐passaged cells. Growth rates, early stages of angiogenesis, perfusion and tissue oxygenation were assessed. Compared with the parental cell line, both ras transformants grew very rapidly and exhibited an early onset of angiogenesis. Perfusion rates of one ras‐transformed tumor line were similar to those of the parental tumors whereas reduced flow values were detected in tumors of the other rats line. The better perfused tumors exhibited more adequate tissue oxygen levels whereas reduced oxygen levels were obvious in the poorly perfused ras line. These results indicate that ras transformation alters therapeutically relevant parameters of the tumor micromilieu. However, the tumor phenotype cannot be predicted even if the transforming oncogene is known.
Clonal dominance of select subsets of viral kirsten ras+‐transformed 3T3 cells during tumor progression
Authors: Radinsky Robert , Culp Lloyd A. 
Published: July 2010

AbstractLong‐term culturing of viral Kirsten‐ras‐oncogene (v‐Ki‐ras)‐transformed BALB/c 3T3 cells (KiMSV) selectively enriches for cells which have deleted the viral oncogene. In contrast, v‐Ki‐ras in vivo is amplified and expression increased in all late‐stage tumors and lung metastases relative to late‐passage KiMSV cells being injected. The nature and significance of these selection processes, in terms of the v‐Ki‐ras gene, have been explored using genetically‐tagged cells, as have the properties of v‐Ki‐ras‐ revertant subclones. Inoculation of KiMSV late‐passage cells (containing ≤5% v‐Ki‐ras+ cells) into nude mice, generated primary and lung metastatic tumors with the v‐Ki‐ras gene at increased dosage in all tumors and their single‐cell clones, isolated at both early and late stages of tumor development; this demonstrates early and specific in vivo selection for v‐Ki‐ras+ cells in both induction and progression of tumors in this system. v‐Ki‐ras‐ revertant subclones, isolated from late‐passage KiMSV cells and inoculated individually into athymic nude mice, yielded tumors for only I of the 4 revertants, with no evidence for v‐Ki‐ras sequences in these tumor cells, thereby revealing a v‐Ki‐ras‐independent mechanism for tumor formation in a small subset of revertant cells. Mixtures of the 4 subclones yielded tumors in all animals, although at a much longer latent period than observed with v‐Ki‐ras+ cells. Experiments with mixtures of v‐Ki‐ras‐ revertant cells and pSV2neo‐tagged/v‐Ki‐ras+ cells (both complex NeoR cell mixtures and individual Neo clones tested) at various cell ratios revealed clonal variability among v‐Ki‐ras+ cells for dominance during tumor formation. Moreover, the complex Neo cell mixtures yielded both primary and metastatic tumors with simplified patterns of pSV2neo integration sites, suggesting that secondary genetic or epigenetic events, in addition to v‐Ki‐ras, contribute to the tumor‐progressing phenotype. These experiments taken together demonstrate (a) clone‐specific early selection of distinct v‐Ki‐ras+ cells amongst themselves and over v‐Ki‐ras‐ cells in both induction and progression of tumors, (b) reduced tumorigenic competence of v‐Ki‐ras‐ revertant cells, with a small subset displaying a v‐Ki‐ras‐independent mechanism for tumor formation in this BALB/c 3T3 system, and (c) the significance of additional genetic or epigenetic events for tumor‐progressing competence in unique subsets of v‐Ki‐ras+ cells.
Definition of the expression of the human carcinoembryonic antigen and non‐specific cross‐reacting antigen in human breast and lung carcinomas
Authors: Robbins Paul F. , Eggensperger Diane , Qi Chen‐Feng , Schlom Jeffrey 
Published: July 2010

AbstractMouse cell lines transfected with carcinoembryonic antigen (CEA) and with 2 other members of the human CEA gene family, non‐specific cross‐reacting antigen (NCA) and biliary glycoprotein (BGP), were used to analyze the specificity of several monoclonal antibodies (MAbs). MAbs COL‐1 and COL‐6 were shown to react with the transfected CEA gene product but not with NCA, confirming previous results. Cells expressing the transfected BGP gene product also failed to react with COL‐1 and COL‐6. The MAb B6.2 reacted with cells expressing the NCA gene product but not with those expressing CEA or BGP. The MAb B1.1 reacted strongly with the transfected CEA and BGP gene products but only weakly with the NCA gene product. These antibodies were then utilized in the histochemical analysis of a number of primary and secondary breast and lung tumors. The results indicate that a majority of breast and lung tumors express CEA, and nearly all breast and lung tumors express NCA. Fairly homogeneous expression of CEA and NCA was seen in the majority of both breast and lung tumors. Our results indicate that CEA may be an important target for immunotherapy in a large number of patients with breast and lung tumors.
Prevalence of HPV in cytomorphologically normal cervical smears, as determined by the polymerase chain reaction, is age‐dependent
Authors: Melkert Peter W. J. , van den Brule Adriaan J.C. , Risse Elle K. J. , van Diest Paul J. , Meijer Chris J. L. M. , Walboomers Jan M. M. , Helmerhorst Theo , Hopman Ellen , Bleker Otto P. , Schipper Marguérite E. I. 
Published: July 2010

AbstractThe prevalence of human papillomavirus (HPV) genotypes in relation to age was investigated by the polymerase chain reaction (PCR) method in cytologically normal smears from 4 different groups of women. Group A consisted of young women from a district population, aged 15–34 years, using oral contraceptives and visiting general practitioners for a check‐up (n = 156); group B were asymptomatic women, aged 35–55, in a district population participating in a triennial screening program for cervical cancer (n = 1555); group C and D consisted of women, seen at the gynecological outpatient department for a wide spectrum of gynecological complaints or for control of their hormonal contraception, aged 15–34 years (n = 2320), and aged 35–55 years (n = 1826) respectively. An HPV (all types) prevalence of 14.1%, 4.1%, 13.9% and 6.6% and an HPV 16/18 prevalence of 3.8%, 0.9%, 3.3% and 1.5% were found in groups A, B, C and D respectively. Statistically significant differences (p value <0.001) in HPV prevalence were found between women aged 15–34 years and women aged 35–55 years in the district population and in the hospital population. No statistically significant differences in HPV 16/18 were observed after age‐matching between women in corresponding age‐classes of both populations. In a 5‐year interval analysis a strong age‐dependent relationship was demonstrated, with a maximum between 20 and 24 years. After the age of 35 a constant level of 1–2% HPV 16/18 was observed. These results indicate that genital HPV infections are age‐dependent and suggest that HPV infections at young age can be transient. The implications of these findings in the context of cervical cancer screening are discussed.
Expression of the different viral mRNAs of human papilloma virus 6 in a squamous‐cell carcinoma of the bladder and the cervix
Authors: Oft M. , Böhm S. , Iftner T. , Wilczynski S. P. 
Published: July 2010

AbstractThe prevalence of HPV6 and HPV11 in benign condylomata or mild dysplasias has led to the view of HPV6/11 as rather harmless viruses in relation to carcinogenesis. However, the detection of HPV6/11 DNA in a number of individual cases of squamous‐cell carcinomas of the anogenital/urinary tract could also point to a possible contribution of these viruses in the development of certain malignancies. Recently we have shown that the transcription of the E6 and E7 genes of HPV6 in benign anogenital condylomata is strictly confined to the basal cell layers of the epithelium, which express c‐fos mRNA. This report describes the in situ hybridization analysis of individual mRNA species of HPV6 in 2 malignant tumours. A consistent feature of both carcinomas was the lack of detectable amounts of E6 mRNA, while the E7 mRNA was the major transcript observed. In situ hybridization with a riboprobe for c‐fos revealed an expression pattern similar to that detected with the E7 probe. Hybridization with a probe specific for mRNA with a coding potential for a full‐length E2 protein yielded weak signals in both carcinomas. Using restriction‐enzyme analysis, we compared the long control region of HPV6 amplified by polymerase chain reaction from both tumours with already known HPV6 subtypes. In contrast to previous reports suggesting a correlation between genetic alterations in the long control region of HPV6 and increased malignant behaviour, our data do not support this hypothesis.
Interleukin 7 enhances the proliferation and effector function of tumor‐infiltrating lymphocytes from renal‐cell carcinoma
Authors: Sica Dante , Rayman Patricia , Stanley Jill , Finke James H. , Klein Eric , Klein Eric , Edinger Mark , Tubbs Raymond R. , Bukowski Ronald 
Published: July 2010

AbstractPrevious studies have documented the effects of IL2 on the growth and effector function of tumor‐infiltrating lymphocytes (TIL) in cancer patients. Since IL7 is known to induce T‐ and NK‐cell responses in the peripheral blood, we examined the immuno‐enhancing effects of IL7 on TIL derived from human renal‐cell carcinoma (RCC). Whereas IL2 induced the growth of freshly isolated TIL in vitro, IL7 was ineffective alone and failed to increase the total number of cells proliferating to IL2. However, IL7 did provide a proliferative signal to TIL that were initially expanded in culture with either IL2 or IL2/IL7 for 2 weeks. IL7 also induced the proliferation of CD4+ and CD8+ TIL lines that have specificity for RCC. The proliferative response induced by IL7 was independent of IL2, since anti‐IL2 antibodies did not block IL7‐induced proliferation of TIL. IL7 did cooperate with anti‐CD3 stimulation for the induction of proliferation; however, the magnitude of this interaction was variable and the response usually additive. In addition, IL7 synergized with anti‐CD3 to induce the secretion of IFNγ from short‐term‐cultured TIL and from a TIL line. Although IL7 did not promote the development of a tumor‐specific T‐cell response from IL2‐expanded TIL, IL7 enhanced lymphokine‐activated killer (LAK) activity from some short‐term‐cultured TIL. These results illustrate that IL7 can potentiate the growth and production of IFNγ from RCC‐reactive TIL and, to a lesser extent, enhance IL2‐induced LAK activity of TIL.
Shedding of GD2 ganglioside in patients with retinoblastoma
Authors: Portoukalian Jacques , David Marie‐Jeanne , Richard Michel , Gain Philippe 
Published: July 2010

AbstractRetinoblastoma is a rare tumor of the young child with an intraocular localization that leads to certain problems of diagnosis. With the aim of defining a biochemical marker—which is still lacking for this disease—the gangliosides of a pool of fresh retinoblastoma tumors were analyzed. The ganglioside pattern was shown to have GM3, GM2, GM1, GD3, GD2, GD1b and GT1b as the major components. The occurrence of a high concentration of GD2 in the tumors led us to investigate the possibility of changes in the level of GD2 in the sera of retinoblastoma patients, using quantitative immunostaining with GD2‐specific mouse monoclonal antibodies (MAbs). In 9 out of 10 tumor‐bearing patients, the serum level of GD2 ganglioside was significantly higher than the average value found in normal individuals. A 2‐year follow‐up of patients showed that successful treatment resulted in a rapid decrease in the serum level of GD2 down to the normal range, from which a subsequent elevation was seen only in relapsing patients. Although the clinical study needs further development, the results obtained to date suggest that GD2 is shed in the serum of tumor‐bearing patients and that the level of GD2 could be a potential serum marker of human retinoblastoma.
Involvement of p53 gene mutations in human endometrial carcinomas
Authors: Honda Tsuyoshi , Kato Hidenori , Imamura Toshiro , Gima Tomonao , Nishida Jun‐Ichi , Sasaki Masahiro , Wake Norio , Hoshi Kazuhiko , Sato Akira 
Published: July 2010

AbstractMutations in the p53 gene are associated with a wide variety of human malignancies. Point mutation in one allele and loss of the remaining one generally lead to inactivation of p53 protein. A high frequency of allelic losses corresponding to the 17p13.3 region that contained the p53 gene sequence was also noted in human endometrial carcinoma. Thus, in order to confirm involvement of the p53 gene in endometrial carcinogenesis, we searched for nucleotide sequence change in this gene in 42 endometrial carcinomas that had been subjected to previous LOH analyses. Using the polymerase‐chain‐reaction‐single‐strand conformation polymorphism (PCR‐SSCP) method, we detected p53 gene mutations in 4 specimens. Two adenocarcinomas with allelic loss on 17p contained a mutant p53 gene in the allele that was retained. One specimen with a p53 gene mutation contained a 17q deletion but was uninformative for LOH on 17p. p53 gene mutation was also noted in the remaining stage‐1 carcinoma, though the 17p deletion was not detected in the previous LOH examination. However, 5 specimens with the LOH on 17p retained the wild‐type p53 gene. In the remaining 33 specimens, both alleles of p53 gene seemed to be normal. The mutations observed in 2 specimens (cases 10 and 24), involving C‐to‐T and T‐to‐G substitutions, were located in a highly conserved region. However, the mutations identified in the remaining 2 cases (29 and 35) were at regions positioned outside conserved stretches.
Granulocyte‐macrophage colony‐stimulating factor induces human melanoma‐cell migration
Authors: Kohn Elise C. , Hollister Gambrill H. , Liotta Lance A. , Schiffmann Elliott , Kohn Elise C. , Wahl Sharon , Dipersio John D. 
Published: July 2010

AbstractTumor metastasis is the primary cause of death for cancer patients. The metastatic cascade requires successful tumor cell invasion into and through vascular and parenchymal barriers. We have shown that autocrine motility factor (AMF, autotaxin) and the insulin‐like growth factors (IGFs) induce tumor‐cell migration. Since granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) has been shown to prime neutrophils for chemotaxis, we have therefore studied the influence of GM‐CSF upon tumor cells and report that GM‐CSF stimulates migration of these cells in a dose‐dependent fashion. The ED50 for A2058 human melanoma cell line chemotaxis to GM‐CSF is approx. 60 pM. The motile response to GM‐CSF was additive to that of IGF‐1 and AMF, both of which are potent attractants for tumor cells. Pre‐treatment of cells for 2 hr with non‐toxic concentrations of pertussis toxin (PT) or amiloride resulted in a 50% inhibition of chemotaxis to GM‐CSF. Therefore, GM‐CSF, through PT‐ and amiloride‐sensitive signal pathways, is a potent attractant for melanoma cells, the response to which is additive to that of other attractants. The presence of the GM‐CSF receptor in A2058 melanoma cells was indicated by Northernblot analysis which identified message transcripts of 2.1 and 3.0 kb. These data emphasize the versatility of the melanoma cell migration response to an array of cytokines, including GM‐CSF.