Differences and homologies of chromosomal alterations within and between breast cancer cell lines : A clustering analysis

Background: The MCF7 (ER+/HER2-), T47D (ER+/HER2-), BT474 (ER+/HER2+) and SKBR3 (ER-/HER2+) breast cancer cell lines are widely used in breast cancer research as paradigms of the luminal and HER2 phenotypes. Although they have been subjected to cytogenetic analysis, their chromosomal abnormalities have not been carefully characterized, and their differential cytogenetic profiles have not yet been established. In addition, techniques such as comparative genomic hybridization (CGH), microarray-based CGH and multiplex ligation-dependent probe amplification (MLPA) have described specific regions of gains, losses and amplifications of these cell lines; however, these techniques cannot detect balanced chromosomal rearrangements (e.g., translocations or inversions) or low frequency mosaicism. Results: A range of 19 to 26 metaphases of the MCF7, T47D, BT474 and SKBR3 cell lines was studied using conventional (G-banding) and molecular cytogenetic techniques (multi-color fluorescence in situ hybridization, M-FISH). We detected previously unreported chromosomal changes and determined the content and frequency of chromosomal markers. MCF7 and T47D (ER+/HER2-) cells showed a less complex chromosomal make up, with more numerical than structural alterations, compared to BT474 and SKBR3 (HER2+) cells, which harbored the highest frequency of numerical and structural aberrations. Karyotype heterogeneity and clonality were determined by comparing all metaphases within and between the four cell lines by hierarchical clustering. The latter analysis identified five main clusters. One of these clusters was characterized by numerical chromosomal abnormalities common to all cell lines, and the other four clusters encompassed cell-specific chromosomal abnormalities. T47D and BT474 cells shared the most chromosomal abnormalities, some of which were shared with SKBR3 cells. MCF7 cells showed a chromosomal pattern that was markedly different from those of the other cell lines. Conclusions: Our study provides a comprehensive and specific characterization of complex chromosomal aberrations of MCF7, T47D, BT474 and SKBR3 cell lines.The chromosomal pattern of ER+/HER2- cells is less complex than that of ER+/HER2+ and ER-/HER2+ cells. These chromosomal abnormalities could influence the biologic and pharmacologic response of cells. Finally, although gene expression profiling and aCGH studies have classified these four cell lines as luminal, our results suggest that they are heterogeneous at the cytogenetic level. © 2014Rondón-Lagos et al.; licensee BioMed Central Ltd

Differences and homologies of chromosomal alterations within and between breast cancer cell lines: A clustering analysis

BACKGROUND: The MCF7 (ER+/HER2-), T47D (ER+/HER2-), BT474 (ER+/HER2+) and SKBR3 (ER-/HER2+) breast cancer cell lines are widely used in breast cancer research as paradigms of the luminal and HER2 phenotypes. Although they have been subjected to cytogenetic analysis, their chromosomal abnormalities have not been carefully characterized, and their differential cytogenetic profiles have not yet been established. In addition, techniques such as comparative genomic hybridization (CGH), microarray-based CGH and multiplex ligation-dependent probe amplification (MLPA) have described specific regions of gains, losses and amplifications of these cell lines; however, these techniques cannot detect balanced chromosomal rearrangements (e.g., translocations or inversions) or low frequency mosaicism. RESULTS: A range of 19 to 26 metaphases of the MCF7, T47D, BT474 and SKBR3 cell lines was studied using conventional (G-banding) and molecular cytogenetic techniques (multi-color fluorescence in situ hybridization, M-FISH). We detected previously unreported chromosomal changes and determined the content and frequency of chromosomal markers. MCF7 and T47D (ER+/HER2-) cells showed a less complex chromosomal make up, with more numerical than structural alterations, compared to BT474 and SKBR3 (HER2+) cells, which harbored the highest frequency of numerical and structural aberrations. Karyotype heterogeneity and clonality were determined by comparing all metaphases within and between the four cell lines by hierarchical clustering. The latter analysis identified five main clusters. One of these clusters was characterized by numerical chromosomal abnormalities common to all cell lines, and the other four clusters encompassed cell-specific chromosomal abnormalities. T47D and BT474 cells shared the most chromosomal abnormalities, some of which were shared with SKBR3 cells. MCF7 cells showed a chromosomal pattern that was markedly different from those of the other cell lines. CONCLUSIONS: Our study provides a comprehensive and specific characterization of complex chromosomal aberrations of MCF7, T47D, BT474 and SKBR3 cell lines. The chromosomal pattern of ER+/HER2- cells is less complex than that of ER+/HER2+ and ER-/HER2+ cells. These chromosomal abnormalities could influence the biologic and pharmacologic response of cells. Finally, although gene expression profiling and aCGH studies have classified these four cell lines as luminal, our results suggest that they are heterogeneous at the cytogenetic level

Vascular effects of serelaxin in patients with stable coronary artery disease:A randomized placebo-controlled trial

Aims: The effects of serelaxin, a recombinant form of human relaxin-2 peptide, on vascular function in the coronary microvascular and systemic macrovascular circulation remain largely unknown. This mechanistic, clinical study assessed the effects of serelaxin on myocardial perfusion, aortic stiffness, and safety in patients with stable coronary artery disease (CAD). Methods and results: In this multicentre, double-blind, parallel-group, placebo-controlled study, 58 patients were randomized 1:1 to 48 h intravenous infusion of serelaxin (30 µg/kg/day) or matching placebo. The primary endpoints were change from baseline to 47 h post-initiation of the infusion in global myocardial perfusion reserve (MPR) assessed using adenosine stress perfusion cardiac magnetic resonance imaging, and applanation tonometry-derived augmentation index (AIx). Secondary endpoints were: change from baseline in AIx and pulse wave velocity, assessed at 47 h, Day 30, and Day 180; aortic distensibility at 47 h; pharmacokinetics and safety. Exploratory endpoints were the effect on cardiorenal biomarkers [N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitivity troponin T (hsTnT), endothelin-1, and cystatin C]. Of 58 patients, 51 were included in the primary analysis (serelaxin, n = 25; placebo, n = 26). After 2 and 6 h of serelaxin infusion, mean placebo-corrected blood pressure reductions of −9.6 mmHg (P = 0.01) and −13.5 mmHg (P = 0.0003) for systolic blood pressure and −5.2 mmHg (P = 0.02) and −8.4 mmHg (P = 0.001) for diastolic blood pressure occurred. There were no between-group differences from baseline to 47 h in global MPR (−0.24 vs. −0.13, P = 0.44) or AIx (3.49% vs. 0.04%, P = 0.21) with serelaxin compared with placebo. Endothelin-1 and cystatin C levels decreased from baseline in the serelaxin group, and there were no clinically relevant changes observed with serelaxin for NT-proBNP or hsTnT. Similar numbers of serious adverse events were observed in both groups (serelaxin, n = 5; placebo, n = 7) to 180-day follow-up. Conclusion: In patients with stable CAD, 48 h intravenous serelaxin reduced blood pressure but did not alter myocardial perfusion

Differences and homologies of chromosomal alterations within and between breast cancer cell lines : A clustering analysis

Background: The MCF7 (ER+/HER2-), T47D (ER+/HER2-), BT474 (ER+/HER2+) and SKBR3 (ER-/HER2+) breast cancer cell lines are widely used in breast cancer research as paradigms of the luminal and HER2 phenotypes. Although they have been subjected to cytogenetic analysis, their chromosomal abnormalities have not been carefully characterized, and their differential cytogenetic profiles have not yet been established. In addition, techniques such as comparative genomic hybridization (CGH), microarray-based CGH and multiplex ligation-dependent probe amplification (MLPA) have described specific regions of gains, losses and amplifications of these cell lines; however, these techniques cannot detect balanced chromosomal rearrangements (e.g., translocations or inversions) or low frequency mosaicism. Results: A range of 19 to 26 metaphases of the MCF7, T47D, BT474 and SKBR3 cell lines was studied using conventional (G-banding) and molecular cytogenetic techniques (multi-color fluorescence in situ hybridization, M-FISH). We detected previously unreported chromosomal changes and determined the content and frequency of chromosomal markers. MCF7 and T47D (ER+/HER2-) cells showed a less complex chromosomal make up, with more numerical than structural alterations, compared to BT474 and SKBR3 (HER2+) cells, which harbored the highest frequency of numerical and structural aberrations. Karyotype heterogeneity and clonality were determined by comparing all metaphases within and between the four cell lines by hierarchical clustering. The latter analysis identified five main clusters. One of these clusters was characterized by numerical chromosomal abnormalities common to all cell lines, and the other four clusters encompassed cell-specific chromosomal abnormalities. T47D and BT474 cells shared the most chromosomal abnormalities, some of which were shared with SKBR3 cells. MCF7 cells showed a chromosomal pattern that was markedly different from those of the other cell lines. Conclusions: Our study provides a comprehensive and specific characterization of complex chromosomal aberrations of MCF7, T47D, BT474 and SKBR3 cell lines.The chromosomal pattern of ER+/HER2- cells is less complex than that of ER+/HER2+ and ER-/HER2+ cells. These chromosomal abnormalities could influence the biologic and pharmacologic response of cells. Finally, although gene expression profiling and aCGH studies have classified these four cell lines as luminal, our results suggest that they are heterogeneous at the cytogenetic level. © 2014Rondón-Lagos et al.; licensee BioMed Central Ltd

PEG Interferon a-2b (PEG-Intron) in Essential Thrombocythemia: Phase II Study for Determination of the Minimum Effective, Safe and Tolerated Dose. Preliminary Data.

In Essential Thrombocythemia (ET) various subsets of patients are satisfactorily treated with Interferons (IFN) alpha (Blood 1996; 87 suppl 1, 581a). Since long-lasting treatment is usually required, the patient compliance is difficult to be maintained mainly because frequent subcutaneous injections are necessary. On the basis of the optimized pharmacokinetics of the new pegilated IFNs alpha weekly administered, a phase II study was designed to determine the minimum effective, safe and tolerated dose of PEG Interferon alpha-2b (PEG-Intron, Schering-Plough) in a cohort of ET patients. The major endpoint of this study, with a sample size of 86 cases, is to evaluate if at the end of the first year of treatment at least 45% of patients reaches the Hematological Response (HR = platelet count 60 yrs (n=12), platelet count > 1000 x 109/L (n=65), previous thrombosis (n=5), peripheral granulocyte precursors (n=7), moderate splenomegaly (n=18), mean platelet count 1112 x109/L, mean Hb level 13.4 g/dl, mean WBC count 9.2 x109/L. Preliminary data of the platelet decrease are shown in the table: week cases platelets Hematological (x109/L) Response** mean % cases % 0 77 1112 100 / / 4 64 831 77 4 6 13 30* 700 64 2 7 18 21 594 52 9 42 22 10 580 47 4 40 * at week 13, 28/30 patients increased PEG-Intron dose (50ug/week) ** platelet count < 500 x 109/LInterestingly, after week 18 the mean platelet count was half of the baseline value and 40% of the patients showed a platelet count < 500 x 109/L. Notably, no WHO grade III or IV toxicity was observed and only one patient decided to withdraw from the study at week 6 due to WHO grade I orticaria. These preliminary data suggest that PEG-Intron, also at low dose, is able in ET patients to significantly decrease the platelet count with a negligible toxicity

Anagrelide in Essential Thrombocythemia: A Retrospective Analysis of 220 Patients. Session Type: Poster Session 646-III

This retrospective study analyses 220 patients with Essential Thrombocythemia (ET) treated with Anagrelide in 26 Institutions of the Gruppo Italiano Malattie Mieloproliferative Croniche (GIMMC). The patients, 81 males and 139 females, at diagnosis had a mean age of 39 years (13-40 years 55%; 41-60 years 35%; 61-82 years 10%) and showed a mean PLT count (109/L) of 1108, previous thrombosis (4.5%), previous hemorrhage (3%), disease related symptoms (20%), cardiovascular risk factors (32%) and splenomegaly (25%). At start of Anagrelide treatment the mean PLT count (109/L) was 907 (>1000 in 32%). The 68% of patients were receiving an antiplatelet treatment and the 74% received cytoreductive drugs (Alkylating agents and HU 17%, HU alone 20%, HU and IFN 21%, IFN alone 16%). The treatment with Anagrelide was started mainly because of the young age of patients, inefficacy and/or high dose required, toxicity and/or side effects of the other drugs and patient request. The mean daily Anagrelide dose from the baseline of 1.3 mg was increased to 1.5 mg after 1 month and to 1.8 mg since the 12th month. The most common side effects were cephalea/vertigo (24%), palpitation/tachycardia (24%), gastrointestinal (9%), asthenia (8%), oedema (5%). A transitory interruption of Anagrelide treatment was observed in 44/220 cases (20%) as a consequence of drug toxicity (3.7%), side effects (5%), no drug availability (4.5%), other causes (6.8%). A drug withdrawal was registered in 54/220 patients (24.5%) after a median treatment duration of 17 months when the mean Anagrelide dose was 1.8 mg/day and the mean PLT count was 665 x109/L), because of inefficacy (3%), toxicity (3%), side effects (9.5%), compliance loss (1%), no drug availability (3%),other causes (5%). The mean follow-up of all 220 patients was 21 months. The mean PLT count (109/L) from the baseline value of 907 decreased to 586, 505, 490, 458 and 449 after 1, 6, 12, 36 and 60 months, respectively. The mean WBC count (109/L) was 7.7 at the baseline and 9.2 after 60 months. The mean Hb level (g/dL) from the baseline of 13.2 decreased to 12.8 and 12.4 at months 6 and 60, respectively. Two minor hemorrhagic events (0.51/100 pt-yrs) and 3 major thrombotic events (0.77/100 pt-yrs) were observed during the follow-up. In this series of ET patients the treatment with the non-mutagenic Anagrelide has been confirmed to be effective and globally well tolerated. Nevertheless, new prospective studies are necessary to define the Anagrelide long-term toxicity, particularly in terms of thrombotic and/or hemorrhagic complications and anemia occurrence