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1.
Ann Surg Oncol ; 31(6): 3758-3768, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38453767

ABSTRACT

BACKGROUND: Before 2016, patients with isolated synchronous colorectal peritoneal metastases (PMCRC) diagnosed in expert centers had a higher odds of undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) and better overall survival (OS) than those diagnosed in referring centers. Nationwide efforts were initiated to increase awareness and improve referral networks. METHODS: This nationwide study aimed to evaluate whether the between-center differences in odds of undergoing CRS-HIPEC and OS have reduced since these national efforts were initiated. All patients with isolated synchronous PMCRC diagnosed between 2009 and 2021 were identified from the Netherlands Cancer Registry. Associations between hospital of diagnosis and the odds of undergoing CRS-HIPEC, as well as OS, were assessed using multilevel multivariable regression analyses for two periods (2009-2015 and 2016-2021). RESULTS: In total, 3948 patients were included. The percentage of patients undergoing CRS-HIPEC increased from 17.2% in 2009-2015 (25.4% in expert centers, 16.5% in referring centers), to 23.4% in 2016-2021 (30.2% in expert centers, 22.6% in referring centers). In 2009-2015, compared with diagnosis in a referring center, diagnosis in a HIPEC center showed a higher odds of undergoing CRS-HIPEC (odds ratio [OR] 1.64, 95% confidence interval [CI] 1.02-2.67) and better survival (hazard ratio [HR] 0.80, 95% CI 0.66-0.96). In 2016-2021, there were no differences in the odds of undergoing CRS-HIPEC between patients diagnosed in HIPEC centers versus referring centers (OR 1.27, 95% CI 0.76-2.13) and survival (HR 1.00, 95% CI 0.76-1.32). CONCLUSION: Previously observed differences in odds of undergoing CRS-HIPEC were no longer present. Increased awareness and the harmonization of treatment for PMCRC may have contributed to equal access to care and a similar chance of survival at a national level.


Subject(s)
Colorectal Neoplasms , Cytoreduction Surgical Procedures , Hyperthermic Intraperitoneal Chemotherapy , Peritoneal Neoplasms , Humans , Peritoneal Neoplasms/therapy , Peritoneal Neoplasms/secondary , Peritoneal Neoplasms/mortality , Cytoreduction Surgical Procedures/mortality , Male , Female , Colorectal Neoplasms/pathology , Colorectal Neoplasms/therapy , Colorectal Neoplasms/mortality , Middle Aged , Survival Rate , Combined Modality Therapy , Aged , Prognosis , Follow-Up Studies , Netherlands , Health Services Accessibility , Registries , Antineoplastic Combined Chemotherapy Protocols/therapeutic use
2.
J Shoulder Elbow Surg ; 33(1): 145-155, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37689102

ABSTRACT

BACKGROUND: Overloading of the elbow joint prosthesis following total elbow arthroplasty can lead to implant failure. Joint moments during daily activities are not well contextualized for a prosthesis's failure limits, and the effect of the current postoperative instruction on elbow joint loading is unclear. This study investigates the difference in elbow joint moments between simulated daily tasks and between flexion-extension, pronation-supination, and varus-valgus movement directions. Additionally, the effect of the current postoperative instruction on elbow joint load is examined. METHODS: Nine healthy participants (age 45.8 ± 17 years, 3 males) performed 8 tasks; driving a car, opening a door, rising from a chair, lifting, sliding, combing hair, drinking, emptying cup, without and with the instruction "not lifting more than 1 kg." Upper limb kinematics and hand contact forces were measured. Elbow joint angles and net moments were analyzed using inverse dynamic analysis, where the net moments are estimated from movement data and external forces. RESULTS: Peak elbow joint moments differed significantly between tasks (P < .01) and movement directions (P < .01). The most and least demanding tasks were, rising from a chair (13.4 Nm extension, 5.0 Nm supination, and 15.2 Nm valgus) and sliding (4.3 Nm flexion, 1.7 Nm supination, and 2.6 Nm varus). Net moments were significantly reduced after instruction only in the chair task (P < .01). CONCLUSION: This study analyzed elbow joint moments in different directions during daily tasks. The outcomes question whether postoperative instruction can lead to decreasing elbow loads. Future research might focus on reducing elbow loads in the flexion-extension and varus-valgus directions.


Subject(s)
Arthroplasty, Replacement, Elbow , Elbow Joint , Male , Humans , Adult , Middle Aged , Elbow Joint/surgery , Elbow , Activities of Daily Living , Movement , Biomechanical Phenomena
3.
Acta Oncol ; 62(8): 842-852, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37548150

ABSTRACT

BACKGROUND: This study investigates whether inequalities in the utilization of resection and/or ablation for synchronous colorectal liver metastases (SCLM) between patients diagnosed in expert and non-expert hospitals changed since a multi-hospital network started. MATERIALS AND METHODS: Patients diagnosed with SCLM between 2009 and 2020 were included. The likelihood of receiving ablation and/or resection was analyzed in the prenetwork (2009-2012), startup (2013-2016), and matured-network (2017-2020) periods. RESULTS: Nationwide, 13.981patients were diagnosed between 2009 and 2020, of whom 1.624 were diagnosed in the network. Of patients diagnosed in the network's expert hospitals, 36.7% received ablation and/or resection versus 28.3% in nonexpert hospitals (p < 0.01). The odds ratio (OR) of receiving ablation and/or resection for patients diagnosed in expert versus nonexpert hospitals increased from 1.38 (p = 0.581, pre-network), to 1.66 (p = 0.108, startup), to 2.48 (p = 0.090, matured-network). Nationwide, the same trend occurred (respectively OR 1.41, p = 0.011; OR 2.23, p < 0.001; OR 3.20, p < 0.001). CONCLUSIONS: Patients diagnosed in expert hospitals were more likely to receive ablation and/or resection for SCLM than patients diagnosed in non-expert hospitals. This difference increased over time despite the startup of a multi-hospital network. Establishing a multi-hospital network did not have an effect on reducing the existing unequal odds of receiving specialized treatment. SYNOPSIS: Specialized oncology treatments are increasingly provided through multi-hospital networks. However, scant empirical evidence on the effectiveness of these networks exists. This study analyzes whether a regional multi-hospital network was able to improve equal access to specialized oncology treatments.


Subject(s)
Colorectal Neoplasms , Liver Neoplasms , Humans , Hepatectomy , Colorectal Neoplasms/pathology , Liver Neoplasms/secondary , Hospitals , Probability , Treatment Outcome
6.
Clin Obes ; 12(2): e12507, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35040265

ABSTRACT

Postbariatric outcomes may improve by providing an additional preconditioning program (APP) in targeted patients. However, APPs are a demand for health resources while only little and inconsistent evidence consists to support their effectiveness. This cohort study aims to evaluate the effectiveness of APP, by comparing outcomes of patients with and without such APP. We carried out a retrospective single-centre cohort study in a before-after design. Patients signing up for primary gastric bypass or sleeve gastrectomy and eligible for surgery were included if screened as vulnerable patients. Vulnerable patients screened between September 2017 and March 2018 followed an APP and formed the APP-group. Due to a policy change, APPs were no longer performed since September 2018. Vulnerable patients screened between September 2018 and March 2019 thus did not receive an APP (comparator-group). Multidisciplinary follow-up remained unchanged. Endpoints included percentage total weight loss (%TWL), bodyweight, evolution of comorbidities, protein intake, and number of no-shows. The APP-group comprised 231 patients and the comparator-group 153. %TWL differed statistically significantly at 7 (Δ1.5%, p = .01) and 12 months postoperative (Δ2.8%, p < .01) in favour of the comparator-group, as did bodyweight 12 months postoperative (Δ1.8 kg, p < .01). Statistically significant differences were also found in the evolution of comorbidities, protein intake, and the number of no-shows, most in favour for the comparator-group. APP proofed not to be superior to Non-App. It is debatable whether statically significant differences are clinically relevant given their small magnitude. A care pathway without an APP seems at least as effective as a care pathway without.


Subject(s)
Bariatric Surgery , Gastric Bypass , Laparoscopy , Obesity, Morbid , Cohort Studies , Gastrectomy/adverse effects , Gastric Bypass/adverse effects , Humans , Obesity, Morbid/etiology , Obesity, Morbid/surgery , Retrospective Studies , Treatment Outcome , Weight Loss
7.
J Fish Biol ; 78(6): 1786-98, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21651528

ABSTRACT

This study showed that the mouth of Doryrhamphus dactyliophorus, a species with a relatively long snout, travels a greater distance compared with Doryrhamphus melanopleura, a species with a considerably shorter snout, allowing it to strike at prey that are farther away from the mouth. The long-snouted species also tended to reach significantly higher linear velocities of the mouth approaching the prey. On the other hand, D. melanopleura needed less time to capture its prey. A striking difference in prey-capture success was observed between species: D. melanopleura and D. dactyliophorus had a prey-capture success of 91 and 31%, respectively. The small prey size and the relatively large distance between eyes and prey are potential reasons why directing the mouth accurately to the prey is difficult in D. dactyliophorus, hence possibly explaining the lower prey-capture success in this long-snouted species.


Subject(s)
Feeding Behavior/physiology , Mouth/physiology , Predatory Behavior/physiology , Smegmamorpha/physiology , Animals , Biomechanical Phenomena , Mouth/anatomy & histology , Smegmamorpha/anatomy & histology
8.
J Exp Med ; 173(6): 1407-19, 1991 Jun 01.
Article in English | MEDLINE | ID: mdl-2033369

ABSTRACT

Antibodies producing an unusual immunofluorescent pattern were identified in the sera of patients with diverse autoimmune features. This pattern was characterized by the presence of up to six round discrete nuclear bodies in interphase cell nuclei. Immunoblotting analysis showed that these sera recognized an 80-kD nuclear protein, and affinity-purified anti-p80 antibody from the protein band reproduced the fluorescent staining of nuclear bodies. Colloidal gold immunoelectron microscopy showed that the affinity-purified anti-p80 antibody recognized the coiled body, an ultramicroscopic nuclear structure probably first described by the Spanish cytologist Ramon y Cajal. Five cDNA clones were isolated from a MOLT-4 cell lambda gt-11 expression library using human antibody and oligonucleotide probes. The longest cDNA insert was 2.1 kb and had an open reading frame of 405 amino acids. A clone encoding a 14-kD COOH-terminal region of the protein was used for expression of a beta-galactosidase fusion protein. An epitope was present in this COOH-terminal 14-kD region, which was recognized by 18 of 20 sera with anti-p80 reactivity, and affinity-purified antibody from the recombinant protein also reacted in immunofluorescence to show specific staining of the coiled body. This is the first demonstration and molecular cloning of a protein that appears to have particular identification with the coiled body, and it was designated p80-coilin. Autoantibody to p80-coilin may be useful for the elucidation of the structure and function of the coiled body, and the availability of a cDNA sequence could be helpful in further studies to clarify the clinical significance of this autoantibody response.


Subject(s)
Autoantibodies/immunology , Autoantigens/genetics , Autoantigens/immunology , Cell Nucleus/immunology , Nuclear Proteins/genetics , Nuclear Proteins/immunology , Amino Acid Sequence , Base Sequence , Blotting, Western , Cell Nucleus/ultrastructure , Cloning, Molecular , DNA/genetics , Fluorescent Antibody Technique , Humans , Molecular Sequence Data , Molecular Weight , Nuclear Proteins/chemistry , Recombinant Proteins/immunology
9.
J Exp Med ; 172(2): 419-29, 1990 Aug 01.
Article in English | MEDLINE | ID: mdl-1695666

ABSTRACT

A cDNA clone encoding full-length human proliferating cell nuclear antigen (PCNA) was used to generate a panel of in vitro translated labeled protein products with COOH-terminal deletions and to construct a set of fusion proteins with COOH- and NH2-terminal deletions. A rabbit antiserum raised against an NH2-terminal peptide, a well-characterized murine monoclonal antibody (mAb), and 14 human lupus sera with autoantibody to PCNA were analyzed for their reactivity with the constructs using both immunoprecipitation and immunoblotting techniques. The rabbit antiserum reacted in immunoprecipitation and immunoblotting with constructs containing the appropriate NH2-terminal sequence and mAb reacted with a sequence from the midregion of PCNA. These experimentally induced antibodies also reacted with 15-mer synthetic peptides in enzyme-linked immunosorbent assay (ELISA). In contrast, none of the lupus sera reacted with synthetic peptides in ELISA. 9 of the 14 lupus sera also failed to react in Western immunoblotting with any recombinant fusion protein, although they all immunoprecipitated in vitro translated full-length protein. Four of the nine had variable patterns of immunoprecipitation with shorter constructs. The remaining five lupus sera were able to immunoprecipitate translation products as well as Western blot recombinant fusion proteins. From analysis of the patterns of reactivity of human lupus sera, it was deduced that the apparent heterogeneity of human autoantibodies to PCNA could be explained by immune response to highly conformational epitopes. These observations demonstrate that there might be special features in "native" epitopes of intranuclear antigens that are recognized by autoantibodies, and that these special features of native epitopes might not be present in prepared antigen used for experimental immunization. These features may be related to protein folding or to association of the antigen with other intranuclear proteins or nucleic acids, as might occur with antigens that are components of subcellular particles.


Subject(s)
Epitopes/genetics , Nuclear Proteins/genetics , Amino Acid Sequence , Animals , Antibodies, Monoclonal , Antigen-Antibody Complex , Autoantigens/genetics , Cell Line , Chromosome Deletion , Cloning, Molecular , DNA, Recombinant/metabolism , Enzyme-Linked Immunosorbent Assay , Epitopes/analysis , Gene Library , Humans , Molecular Sequence Data , Nuclear Proteins/immunology , Peptides/chemical synthesis , Peptides/immunology , Proliferating Cell Nuclear Antigen , Rats , Restriction Mapping
10.
Br J Cancer ; 103(8): 1255-62, 2010 Oct 12.
Article in English | MEDLINE | ID: mdl-20842112

ABSTRACT

BACKGROUND: Wilms' tumour 1 (WT1) gene was discovered as a tumour suppressor gene. Later findings have suggested that WT1 also can be oncogenic. This complexity is partly explained by the fact that WT1 has a number of target genes. METHOD: WT1 and its target gene human telomerase reverse transcriptase (hTERT) were analysed in clear cell renal cell carcinoma (ccRCC). In vitro experiments were performed to examine the functional link between WT1 and hTERT by overexpression of WT1 isoforms in the ccRCC cell line, TK-10. RESULTS: WT1 demonstrated lower RNA expression in ccRCC compared with renal cortical tissue, whereas hTERT was increased, showing a negative correlation between WT1 and hTERT (P=0.005). These findings were experimentally confirmed in vitro. The WT1 generated effect on hTERT promoter activity seemed complex, as several negative regulators of hTERT transcription, such as SMAD3, JUN (AP-1) and ETS1, were activated by WT1 overexpression. Downregulation of potential positive hTERT regulators, such as cMyc, AP-2α, AP-2γ, IRF1, NFX1 and GM-CSF, were also observed. Chromatin immunoprecipitation analysis verified WT1 binding to the hTERT, cMyc and SMAD3 promoters. CONCLUSION: The collected data strongly indicate multiple pathways for hTERT regulation by WT1 in ccRCC.


Subject(s)
Carcinoma, Renal Cell/genetics , Kidney Neoplasms/genetics , Telomerase/genetics , Telomerase/metabolism , WT1 Proteins/physiology , Carcinoma, Renal Cell/enzymology , Cell Line, Tumor , Down-Regulation , Enzyme Activation , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , Genes, myc , Humans , Kidney Neoplasms/enzymology , Promoter Regions, Genetic , Protein Binding , Signal Transduction/genetics , Signal Transduction/physiology , Transfection , WT1 Proteins/genetics , WT1 Proteins/metabolism
11.
Leukemia ; 20(1): 77-81, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16307023

ABSTRACT

The G(-248)A polymorphism in the promoter region of the Bax gene was recently associated with low Bax expression, more advanced stage, treatment resistance and short overall survival in B-cell chronic lymphocytic leukemia (CLL), the latter particularly in treated patients. To investigate this further, we analyzed 463 CLL patients regarding the presence or absence of the G(-248)A polymorphism and correlated with overall survival, treatment status and known prognostic factors, for example, Binet stage, VH mutation status and genomic aberrations. In this material, similar allele and genotype frequencies of the Bax polymorphism were demonstrated in CLL patients and controls (n=207), where 19 and 21% carried this polymorphism, respectively, and no skewed distribution of the polymorphism was evident between different Binet stages and VH mutated and unmutated CLLs. Furthermore, no difference in overall survival was shown between patients displaying the G(-248)A polymorphism or not (median survival 85 and 102 months, respectively, P=0.21), and the polymorphism did not influence outcome specifically in treated CLL. Neither did the polymorphism affect outcome in prognostic subsets defined by VH mutation status or genomic aberrations. In conclusion, the pathogenic role and clinical impact of the Bax polymorphism is limited in CLL.


Subject(s)
Biomarkers, Tumor/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Polymorphism, Genetic/genetics , Promoter Regions, Genetic , bcl-2-Associated X Protein/genetics , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/biosynthesis , Cohort Studies , Cytogenetic Analysis , Female , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Male , Middle Aged , Prognosis , Retrospective Studies , Survival Rate , bcl-2-Associated X Protein/biosynthesis
12.
Cancer Res ; 51(17): 4570-4, 1991 Sep 01.
Article in English | MEDLINE | ID: mdl-1678682

ABSTRACT

The usefulness of different anti-proliferating cell nuclear antigen monoclonal antibodies as S-phase probes in flow cytometric analysis was evaluated after various fixation procedures on human cell lines. With a newly developed detergent extraction/fixation method the monoclonal antibody PC10 acted as a selective S-phase marker. A total of 27 human hematopoietic tumors were analyzed using PC10, and all exhibited the characteristic S-phase recognition pattern. The percentage of PC10-positive cells was easily calculated and showed strong correlation to the fraction of S-phase cells determined from DNA histograms. Using alternative fixation procedures PC10, on the other hand, could recognize all actively cycling cells, a feature also observed for the monoclonal antibodies, 19A2 and TOB7.


Subject(s)
Antibodies, Monoclonal , Antigens, Neoplasm/immunology , DNA Replication , DNA, Neoplasm/analysis , Nuclear Proteins/immunology , S Phase , Cell Line , Flow Cytometry , Humans , Proliferating Cell Nuclear Antigen
13.
Cancer Res ; 36(11 Pt 1): 4044-51, 1976 Nov.
Article in English | MEDLINE | ID: mdl-61800

ABSTRACT

A HeLa cell line synchronized by double thymidine block and mitotic shake off was shown to have a characteristic surface morphology for each of the different cell cycle stages. Inhibitors of cell multiplication were used to arrest cells in specific cell cycle phases, and these cells had a surface morphology similar to that of synchronized cells in the same phase. The results indicated a close association between the cell surface topography and the cycles of DNA synthesis in the cell nucleus of this HeLa line.


Subject(s)
Cell Division , HeLa Cells/ultrastructure , Bleomycin/pharmacology , Cell Division/drug effects , Cell Membrane/metabolism , Cell Membrane/ultrastructure , Cytarabine/pharmacology , HeLa Cells/metabolism , Humans , Hydrocortisone/pharmacology , Hydroxyurea/pharmacology , Microscopy, Electron, Scanning , Mitomycins/pharmacology , Mitosis/drug effects , Thymidine/metabolism , Time Factors , Vinblastine/pharmacology
14.
Cancer Res ; 54(1): 236-41, 1994 Jan 01.
Article in English | MEDLINE | ID: mdl-8261445

ABSTRACT

The ends of human chromosomes consist of a specialized structure, the telomere, composed of repeats of TTAGGG making up a total of 5-15 kilobase pairs, depending on age and proliferative activity of the tissue. The major function of telomeres is to provide stability to chromosomes and protect underlying unique coding sequences from degradation. There is a loss of telomeric sequences following every cell division estimated to be between 50 and 65 basepairs/cell division in human fibroblasts and embryonic kidney cells in vitro. This loss is due to the fact that DNA replication is incomplete for one strand at each telomere end. In lower eukaryotes there is a compensation mechanism provided by the enzyme telomerase, which is inactive in human somatic cells. Telomerase activation has also been detected in vitro immortalized human cells. In this study we analyzed renal cell carcinoma for the occurrence of telomere shortening using the probe (TTAGGG)4. Southern blots of HinfI-digested DNA revealed a shortening of mean telomere restriction fragment (TRF) length of 0.4 to 2.5 kilobase pairs in 2 or 3 intratumoral samples in all 10 tumors analyzed. No obvious intratumoral heterogeneity was found in mean TRF length values. However, heterogeneity was shown by the occurrence of at least two separate peak TRF values in 7 of 10 tumors, indicating the presence of different tumor cell clones. A conflicting observation was made when we evaluated the intensity of the hybridization signals, where three of the tumors showed an increase in hybridization signals despite concomitant TRF reduction. We found no correlation between tumor size and calculated tumor cell divisions undergone. In two tumors, the calculated cell division cycles were unrealistically low compared to the tumor size. These data suggest that telomerase activation might occur in human renal cell carcinoma.


Subject(s)
Carcinoma, Renal Cell/genetics , DNA, Neoplasm/analysis , Kidney Neoplasms/genetics , Telomere/chemistry , Base Sequence , Carcinoma, Renal Cell/pathology , Cell Division/genetics , Humans , Kidney Neoplasms/pathology , Molecular Sequence Data , Nucleic Acid Hybridization
15.
Cancer Res ; 48(11): 3165-7, 1988 Jun 01.
Article in English | MEDLINE | ID: mdl-3365699

ABSTRACT

Local and distant tumor spread was evaluated and compared with DNA content analyzed by flow cytometry of eight samples from each of 71 renal cell carcinomas. Twenty-six tumors were homogenously diploid while 45 tumors contained at least one aneuploid tumor sample. Diploid tumors generally respected the surrounding tissues and only three of 26 tumors (12%) had evidence of local tumor invasion. In contrast, 33 of 45 patients (73%) with aneuploid tumors had local invasion (p less than 0.001). Local metastases in lymph nodes and adrenal was found only in patients with aneuploid tumors. However, distant metastases appeared in about the same frequency in patients with diploid and aneuploid tumors (35 and 29%, respectively). Patients with diploid tumors had significantly more often solitary metastases and, most interestingly, the occurrence of lung metastases was a characteristic feature for patients with aneuploid tumors (p less than 0.02). The diploid primary tumors with distant metastases generally were devoid of local invasion while all aneuploid tumors with distant metastases had local invasion and mostly also local metastases. Thus, different characteristics of tumor spread were shown for diploid and aneuploid tumors and the pathways for spread with distant metastases might also differ between these tumors.


Subject(s)
Carcinoma, Renal Cell/pathology , DNA, Neoplasm/analysis , Kidney Neoplasms/pathology , Neoplasm Metastasis/pathology , Aneuploidy , Carcinoma, Renal Cell/surgery , Diploidy , Humans , Kidney Neoplasms/surgery , Neoplasm Invasiveness , Nephrectomy
16.
Cancer Res ; 44(6): 2358-62, 1984 Jun.
Article in English | MEDLINE | ID: mdl-6722775

ABSTRACT

A panel of 26 human hematopoietic cell lines was tested for sensitivity to growth inhibition towards interferon-alpha (IFN-alpha) by estimating the effects on cell cycle phase distribution using flow cytometry analysis. The proportion of proliferating cells was assessed by studying the fractional increase of cells in mitosis during a 24-hr vinblastine block. Of 26 cell lines tested, 17 were sensitive to IFN-alpha, and the main cell cycle effect was accumulation in the G0-G1 phase. One Burkitt's lymphoma line, Namalwa, showed a decreased rate of progress through S without any G0/G1 accumulation. Three of the cell lines were also tested with IFN-beta and with IFN-alpha 2 produced by recombinant DNA technology. The latter IFN did not affect one of the cell lines; otherwise, the results were similar to those of IFN-alpha. Six of 16 clinical specimens from patients with hematopoietic neoplasias were IFN-sensitive, all displaying a G0-G1 block. Our results indicate that IFN sensitivity is an individually linked property unrelated to cell origin.


Subject(s)
Cell Cycle/drug effects , Hematopoietic Stem Cells/physiology , Interferon Type I/toxicity , Leukemia/physiopathology , Lymphoma/physiopathology , Cell Division/drug effects , Cell Line , Hematopoietic Stem Cells/drug effects , Humans , Kinetics
17.
Cancer Res ; 42(5): 1955-61, 1982 May.
Article in English | MEDLINE | ID: mdl-7066906

ABSTRACT

Copper- and zinc-containing superoxide dismutase, manganese-containing superoxide dismutase, catalase, and glutathione peroxidase form the primary enzymic defense against toxic oxygen reduction metabolites. Such metabolites have been implicated in the damage brought about by ionizing radiation, as well as in the effects of several cytostatic compounds. These enzymes were analyzed in 31 different human normal diploid and neoplastic cell lines and for comparison in 15 normal human tissues. The copper- and zinc-containing superoxide dismutase appeared to be slightly lower in malignant cell lines in general as compared to normal tissues. The content of manganese superoxide dismutase was more variable than the content of the copper- and zinc-containing enzyme. Contrary to what has been suggested before, this enzyme did not appear to be generally lower in malignant cells compared to normal cells. One cell line, of mesothelioma origin (P27), was extremely abundant in manganese-containing superoxide dismutase; the concentration was almost an order of magnitude larger than in the richest normal tissue. Catalase was very variable both among the normal tissues and among the malignant cells, whereas glutathione peroxidase was more evenly distributed. In neither case was a general difference between normal cells and tissues and malignant cells apparent. The myocardial damage brought about by doxorubicin has been linked to toxic oxygen metabolites; particularly, an effect on the glutathione system has been noted. The heart is one of the tissues which have a low concentration of enzymes which protect against hydroperoxides. However, the deviation from other tissues is probably not large enough to provide a full explanation for the high doxorubicin susceptibility. In the present survey, no obvious relationship between generally assumed resistance to ionizing radiation or to radical-producing drugs and cellular content of any of the enzymes could be demonstrated.


Subject(s)
Catalase/analysis , Glutathione Peroxidase/analysis , Neoplasms/enzymology , Peroxidases/analysis , Superoxide Dismutase/analysis , Cell Line , Copper , Free Radicals , Humans , Manganese , Oxidation-Reduction , Zinc
18.
Cancer Res ; 57(3): 549-54, 1997 Feb 01.
Article in English | MEDLINE | ID: mdl-9012489

ABSTRACT

Deregulation of the cell cycle by abnormal expression of one or several cell cycle regulatory proteins is a common finding in malignant tumors and might be a prerequisite for cancer development. Telomerase activity is an immortalization marker that is found in most cancers and for which an association with an active cell cycle has been implicated. In the tissue of 106 human breast carcinomas, we analyzed the relationship between telomerase activity levels and defects in the cell cycle machinery with a focus on the retinoblastoma protein (pRB) pathway(s). The fraction of telomerase-positive tumors was 85%, and large differences in telomerase activity were found. Overexpression of cyclin D1 and/or cyclin E, in combination with a normal pRB, was a typical feature of tumors with high telomerase activity levels. Down-regulation of p16INK4 was not related per se to telomerase activity, but tumors with low p16INK4 in combination with cyclin D1 or E overexpression demonstrated high activity. Tumor cell proliferation, determined by Ki-67 expression, correlated significantly to telomerase activity levels. There was, however, not a strict association between proliferation rate and telomerase activity, because tumors with inactivated pRB had the highest Ki-67 fractions but intermediate telomerase activity. Also, cyclin D1 overexpression was associated with high telomerase levels without an increase in tumor cell proliferation. The present study indicates that telomerase activation occurs preferentially in breast cancers with certain cell cycle regulatory defects and that telomerase activity levels may depend on the specific defect(s).


Subject(s)
Breast Neoplasms/enzymology , Cell Cycle , Telomerase/metabolism , Breast Neoplasms/pathology , Carrier Proteins/analysis , Cell Division , Cyclin D1 , Cyclin-Dependent Kinase Inhibitor p16 , Cyclins/analysis , Female , Humans , Oncogene Proteins/analysis , Retinoblastoma Protein/analysis
19.
Oncogene ; 9(10): 3043-8, 1994 Oct.
Article in English | MEDLINE | ID: mdl-8084612

ABSTRACT

In somatic cells, each DNA replication round gives a shortening of the telomere ends as a consequence of incomplete lagging strand synthesis. Telomeres are essential for chromosomal integrity and extensive telomere length reduction is associated with increased instability of the genome. In germ line cells and in established cell lines, telomerase activity maintains the length of the telomeres by de novo synthesis of telomeric repeats, in humans (T2AG3)n. Recently, it was for the first time shown the existence of telomerase activity in human ovarian carcinomas. In the present study we show that telomerase activation can also occur in human hematopoietic tumor cells in vivo. Cell extracts from 19 cases with leukemia, lymphoma and myeloma were tested for telomerase activity using an in vitro assay with (T2AG3)3 or permutations of this sequence as primers. Eight cases demonstrated an RNAse A sensitive ability to add new nucleotides to the human telomere sequence. Nine acute leukemias were tested telomerase negative. Our data demonstrate that telomerase activation in vivo seems to be a common event in B cell neoplasias with a mature immunophenotype like non-Hodgkin's lymphoma and myeloma, in contrast to acute leukemias of B, T or myeloid cell origin. Telomere length evaluation indicated no marked differences between samples with or without telomerase activity which could argue for a telomere length independent mechanism for telomerase activation in at least some cases.


Subject(s)
DNA Nucleotidylexotransferase/metabolism , Leukemia/enzymology , Lymphoma/enzymology , Multiple Myeloma/enzymology , Base Sequence , DNA Primers , Humans , Molecular Sequence Data , Tumor Cells, Cultured
20.
Oncogene ; 13(1): 161-6, 1996 Jul 04.
Article in English | MEDLINE | ID: mdl-8700542

ABSTRACT

Telomeres have a vital role in maintaining chromosome stability and are essential for long term viability. Since the very ends of linear chromosomes cannot replicate, telomeres shorten in normal somatic cells eventually resulting in growth inhibition. However, most immortal cell lines maintain stable telomeres indicating that mechanisms exist to compensate for the end replication problem. Telomerase activity, leading to synthesis of telomeric DNA repeats, has been proposed to be an important step in the immortalization process of tumor cells. In the present study, 56 renal cell carcinomas were tested for telomerase activity using the sensitive TRAP (telomeric repeat amplification protocol). Forty of the analysed tumors (71%) were positive for telomerase activity, whereas none of the 56 corresponding normal kidney samples showed telomerase activity. All telomerase negative tumors had a reduction in mean telomere restriction fragment (TRF) length and a decrease in total telomere repeat hybridization signal, though cases were observed with an increase in peak TRF lengths. No obvious association between the presence of telomerase activity and clinicopathological parameters (histopathologic grade, DNA-ploidy, stage and clinical outcome) was found. The high frequency of detection of telomerase activity in the renal cell carcinomas indicates that this enzyme is likely to be an important factor involved in the evolution of this tumor type.


Subject(s)
Carcinoma, Renal Cell/metabolism , Kidney Neoplasms/enzymology , Neoplasm Proteins/metabolism , Telomerase/metabolism , Base Sequence , Carcinoma, Renal Cell/mortality , Carcinoma, Renal Cell/pathology , DNA, Neoplasm/genetics , DNA, Neoplasm/metabolism , Humans , Kidney Neoplasms/mortality , Kidney Neoplasms/pathology , Molecular Sequence Data , Repetitive Sequences, Nucleic Acid , Telomere/metabolism
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