| 1. |
- Johannsson, Oskar T, et al.
(författare)
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Characterization of a novel breast carcinoma xenograft and cell line derived from a BRCA1 germ-line mutation carrier
- 2003
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Ingår i: Laboratory Investigation. - 1530-0307. ; 83:3, s. 96-387
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Tidskriftsartikel (refereegranskat)abstract
- A human tumor xenograft (L56Br-X1) was established from a breast cancer axillary lymph node metastasis of a 53-year-old woman with a BRCA1 germ-line nonsense mutation (1806C>T; Q563X), and a cell line (L56Br-C1) was subsequently derived from the xenograft. The xenograft carries only the mutant BRCA1 allele and expresses mutant BRCA1 mRNA but no BRCA1 protein as determined by immunoprecipitation or Western blotting. The primary tumor, lymph node metastasis, and xenograft were hypodiploid by DNA flow cytometry, whereas the cell line displayed an aneuploidy apparently developed via polyploidization. Cytogenetic analysis, spectral karyotyping, and comparative genomic hybridization of the cell line revealed a highly complex karyotype with numerous unbalanced translocations. The xenograft and cell line had retained a somatic TP53 missense mutation (S215I) originating from the primary tumors, as well as a lack of immunohistochemically detectable expression of steroid hormone receptors, epidermal growth factor receptor, human epidermal growth factor receptor 2 (HER-2), and keratin 8. Global gene expression analysis by cDNA microarrays supported a correlation between the expression profiles of the primary tumor, lymph node metastasis, xenograft, and cell line. We conclude that L56Br-X1 and L56Br-C1 are useful model systems for studies of the pathogenesis and new therapeutic modalities of BRCA1-induced human breast cancer.
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| 2. |
- Adeyinka, Adewale, et al.
(författare)
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Comparative cytogenetic and DNA flow cytometric analysis of 242 primary breast carcinomas
- 2003
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Ingår i: Cancer Genetics and Cytogenetics. - 0165-4608. ; 147:1, s. 62-67
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Tidskriftsartikel (refereegranskat)abstract
- The cytogenetic and DNA flow cytometric findings in 242 breast carcinomas were compared. The combined use of both techniques improved the detection of abnormal cell populations from 65% by cytogenetic analysis alone and 59% by DNA flow cytometric analysis alone to 84%. Informative and comparable cytogenetic and flow cytometric data were obtained for 155 tumors. Among these 155 tumors, there was good concordance (64%) between the estimates of genomic changes by the two methods. Most discrepancies were among the DNA-diploid cases, where cytogenetic analysis detected small genomic changes. There were, however, also some exceptions in which large genomic changes detected by one method were missed by the other. Of the specific breast cancer-associated cytogenetic aberrations subjected to separate correlation analysis, polysomy for chromosome 20 was significantly associated with a high S-phase fraction, whereas loss of the long arm of chromosome 16 and/or the presence of a der(1;16) were significantly associated with a low S-phase fraction. Our data show that cytogenetic and DNA flow cytometric analyses of breast carcinomas give largely comparable results, and that combining data from both methods significantly improves the information obtained by either technique used alone on the genetic abnormalities in these tumors.
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| 3. |
- Bagwell, C B, et al.
(författare)
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Optimizing flow cytometric DNA ploidy and S-phase fraction as independent prognostic markers for node-negative breast cancer specimens
- 2001
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Ingår i: Cytometry. - : Wiley. - 0196-4763 .- 1097-0320. ; 46:3, s. 121-135
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Tidskriftsartikel (refereegranskat)abstract
- Developing a reliable and quantitative assessment of the potential virulence of a malignancy has been a long-standing goal in clinical cytometry. DNA histogram analysis provides valuable information on the cycling activity of a tumor population through S-phase estimates; it also identifies nondiploid populations, a possible indicator of genetic instability and subsequent predisposition to metastasis. Because of conflicting studies in the literature, the clinical relevance of both of these potential prognostic markers has been questioned for the management of breast cancer patients. The purposes of this study are to present a set of 10 adjustments derived from a single large study that optimizes the prognostic strength of both DNA ploidy and S-phase and to test the validity of this approach on two other large multicenter studies. Ten adjustments to both DNA ploidy and S-phase were developed from a single node-negative breast cancer database from Baylor College (n = 961 cases). Seven of the adjustments were used to reclassify histograms into low-risk and high-risk ploidy patterns based on aneuploid fraction and DNA index optimum thresholds resulting in prognostic P values changing from little (P < 0.02) or no significance to P < 0.000005. Other databases from Sweden (n = 210 cases) and France (n = 220 cases) demonstrated similar improvement of DNA ploidy prognostic significance, P < 0.02 to P < 0.0009 and P < 0.12 to P < 0.002, respectively. Three other adjustments were applied to diploid and aneuploid S-phases. These adjustments eliminated a spurious correlation between DNA ploidy and S-phase and enabled them to combine independently into a powerful prognostic model capable of stratifying patients into low, intermediate, and high-risk groups (P < 0.000005). When the Baylor prognostic model was applied to the Sweden and French databases, similar significant patient stratifications were observed (P < 0.0003 and P < 0.00001, respectively). The successful transference of the Baylor prognostic model to other studies suggests that the proposed adjustments may play an important role in standardizing this test and provide valuable prognostic information to those involved in the management of breast cancer patients.
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| 4. |
- Baldetorp, Bo, et al.
(författare)
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DNA and cell cycle analysis as prognostic indicators in breast tumors revisited
- 2001
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Ingår i: Clinics in Laboratory Medicine. - 0272-2712 .- 1557-9832. ; 21:4, s. 875-
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Tidskriftsartikel (refereegranskat)abstract
- Both DNA ploidy and S-phase ploidy are promising prognostic factors for node-negative breast cancer patients. Based largely on the analysis of one large study, much of the reported problems with these factors have been caused by some unappreciated complexities in categorizing DNA ploidy into low- and high-risk groups and the lack of some necessary adjustments to eliminate unwanted correlations between DNA S-phase and ploidy. When both DNA ploidy and S-phase are compensated properly, they become independent prognostic markers, forming a powerful prognostic model.
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| 5. |
- Baldetorp, Bo, et al.
(författare)
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Improved DNA flow cytometric, DNA ploidy, and S-phase reproducibility between 15 laboratories in analysis of breast cancer using generalized guidelines
- 2003
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Ingår i: Cytometry. - : Wiley. - 0196-4763 .- 1097-0320. ; 56A:1, s. 1-7
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundLack of generalized guidelines for DNA flow cytometric analysis (FCM) may be the main reason for its limited use in the clinical management of breast cancer.MethodsAfter an initial interlaboratory reproducibility study (Round I), we concluded that it was the evaluation of the DNA histograms rather than the technical performance of the analysis that was the main reason for discordant results between laboratories. Guidelines for the interpretation of DNA histograms were therefore drawn up. We present here data from a new reproducibility study (Round II) using these guidelines.ResultsFor 10 laboratories also participating in Round I, use of the guidelines increased the concordance in DNA ploidy status from 89% to 100% for the 46 samples used in both rounds. The concordance rate for SPF also increased; mean rs-value increased from 0.81 to 0.88, and mean kappa value (lower two-thirds versus upper third versus not reported) increased from 0.55 to 0.71. Five new laboratories, participating only in Round II, also agreed with the 10 original laboratories regarding DNA ploidy status. With the inclusion of all 15 laboratories, we obtained a mean rs-value of 0.81 and a mean kappa value of 0.72 for SPF.ConclusionsGeneralized guidelines for DNA FCM increase interlaboratory agreement, which is highly important in clinical routines and in multicenter studies. Furthermore, inexperienced FCM laboratories using generalized guidelines can produce and interpret DNA FCM data equally as well as experienced laboratories.
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| 6. |
- Dreinhofer, KE, et al.
(författare)
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DNA ploidy in soft tissue sarcoma: Comparison of flow and image cytometry with clinical follow-up in 93 patients : comparison of flow and image cytometry with clinical follow-up in 93 patients
- 2002
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Ingår i: Cytometry. - : Wiley. - 0196-4763. ; 50:1, s. 19-24
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Tidskriftsartikel (refereegranskat)abstract
- In soft tissue sarcoma, the prognostic importance of DNA ploidy status is limited. One possible explanation may be technical; small nondiploid stemlines will he diluted in relation to the presence of normal diploid cells and may not be detected by flow cytometry (FCM). We assessed DNA ploidy status in 93 tumors with both FCM and image cytometry (ICM). ICM may permit the exclusion of nonrelevant cells. The ability of the two methods to detect nondiploid stemlines was compared, as were the prognostic consequences. The patients (54 males) had a median age of 69 years. Surgical procedures were performed on all patients. None of the patients had received preoperative radiotherapy or chemotherapy. FCM and ICM were performed with standard methods. The prognostic value was assessed with univariate and multivariate analysis. In 82 of the 93 tumors, a concordant ploidy status by FCM and ICM was found. In 5 FCM type 1-2 tumors (diploid), the identification of nondiploid stemlines by ICM did not influence the metastatic rates. Increasing tumor size, histotype other than liposarcoma, increasing malignancy grade, tumor necrosis, and ICM nondiploidy were univariate prognostic factors for metastasis. In a multivariate analysis, only tumor size larger than 9 cm was a prognostic factor. In about 10% of the tumors, a discrepancy between FCM and ICM ploidy status was found, but we could not find a consistent prognostic consequence of this. Neither FCM nor ICM ploidy status was an independent prognostic factor. (C) 2002 Wiley-Liss, Inc.
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| 7. |
- Fernö, Mårten, et al.
(författare)
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Results of two or five years of adjuvant tamoxifen correlated to steroid receptor and S-phase levels
- 2000
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Ingår i: Breast Cancer Research and Treatment. - 1573-7217 .- 0167-6806. ; 59:1, s. 69-76
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Tidskriftsartikel (refereegranskat)abstract
- A Swedish cooperative trial demonstrated that 5 years of adjuvant tamoxifen was more beneficial than 2 years of tamoxifen in the treatment of postmenopausal women with estrogen receptor (ER) positive, early stage, invasive breast cancer. The main aim of the present study was to investigate the importance of progesterone receptor (PgR) and ER concentration levels for patients participating in the trial and still distant recurrence free two years after the primary operation. Subgroup analyses revealed that only patients with ER positive and PgR positive breast cancer had improved distant recurrence free survival (DRFS) by prolonged tamoxifen therapy (p = 0.0016). Patients with ER negative and PgR negative as well as ER positive and PgR negative tumors showed no significant effect of prolonged tamoxifen (p = 0.53 and p = 0.80, respectively). The percentage of ER negative and PgR positive breast cancers was too small (2.2%) for any meaningful subgroup analysis. There was a significant positive trend that the concentration level of PgR (high positive vs. low positive vs. negative) decreased the recurrence rate for those with prolonged therapy. No corresponding pattern was found for the ER content. S-phase fraction did not correlate to the recurrence rate of PgR positive breast cancers. Patients recurring during tamoxifen therapy had receptor negative tumors to a greater extent than those recurring after tamoxifen treatment. In conclusion, prolonged tamoxifen therapy for 5 years instead of 2 years was found to be beneficial for patients with ER positive and PgR positive breast cancer, whereas three extra years of tamoxifen had little or no effect for patients with ER positive but PgR negative tumors as well as for steroid receptor negative patients.
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| 8. |
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| 9. |
- Hakansson, P., et al.
(författare)
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Establishment and phenotypic characterization of human U937 cells with inducible P210 BCR/ABL expression reveals upregulation of CEACAM1 (CD66a)
- 2004
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Ingår i: Leukemia. - : Springer Science and Business Media LLC. - 0887-6924 .- 1476-5551. ; 18:3, s. 538-47
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Tidskriftsartikel (refereegranskat)abstract
- Chronic myeloid leukemia (CML) is characterized by the expression of the P210 BCR/ABL fusion protein. The molecular mechanisms behind this oncogene-mediated hematological disease are, however, not fully understood. Here, we describe the establishment and phenotypic characterization of U937 cells in which P210 BCR/ABL can be conditionally expressed using tetracycline. The induction of BCR/ABL in the obtained clones resulted in a rapid phosphorylation of the STAT1, STAT3 and STAT5 molecules, consistent with the findings in other model systems. Phenotypic characterization of the clones revealed that BCR/ABL induces a slight decrease in the proliferation and viability, without a marked effect on cell cycle distribution, the rate of apoptosis or on cellular differentiation, as judged by several cell surface markers and capacity to reduce nitro blue tetrazolium. Interestingly, BCR/ABL was found to upregulate the expression of carcinoembryonic-related antigen (CEA)CAM1 (CD66a), which is a plasma membrane-linked glycoprotein belonging to the CEAs and involved in signal transduction and cellular adhesion. The expression of CEACAM1 was reversible upon imatinib treatment in BCR/ABL-expressing U937 cells as well as in BCR/ABL-positive K562 cells. The established cell lines may prove useful in further modeling and dissection of BCR/ABL-induced leukemogenesis.
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| 10. |
- Högberg, Thomas, 1947-, et al.
(författare)
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A prospective population-based management program including primary surgery and postoperative risk assessment by means of DNA ploidy and histopathology. Adjuvant radiotherapy is not necessary for the majority of patients with FIGO stage I-II endometrial cancer
- 2004
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Ingår i: International Journal of Gynecological Cancer. - : BMJ. - 1048-891X .- 1525-1438. ; 14:3, s. 437-450
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Tidskriftsartikel (refereegranskat)abstract
- A management program for FIGO stage I-II nonserous, nonclear-cell adenocarcinomas was evaluated. Histopathology and DNA ploidy were used to estimate postoperatively the risk of progression or death of disease and to tailor treatment. The patient material was a population-based consecutive cohort of all women with endometrial cancer in the Southern Swedish Health Care Region diagnosed between June 1993 and June 1996 (n = 553). Of these, 335 were eligible for the management program. Patients estimated to be at low risk were treated by surgery only, while high-risk patients also received vaginal brachytherapy. A large low-risk group consisting of 84% (n = 283) of the patients with an estimated disease-specific 5-year survival of 96% (95% CI = 93-98%) was identified. The high-risk group (n = 52, 16%) showed a worse outcome with an 80% 5-year disease-specific survival (95% CI = 65-89%). The difference in survival between the groups was highly significant (P < 0.0001). Half of the progressions were distant in the high-risk group. Although there is a clear indication for adjuvant therapy for this group, locoregional radiotherapy could be expected to fail in cases with distant progression. Thus, effective systemic treatments need to be developed. Low-risk patients, constituting the majority (84%) of the patients, can be safely treated by surgery only.
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