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1.
Br J Surg ; 107(6): 655-661, 2020 05.
Article in English | MEDLINE | ID: mdl-32057103

ABSTRACT

BACKGROUND: Safe laparoscopic cholecystectomy may necessitate biliary imaging, and non-invasive fluorescence cholangiography may have advantages over contrast X-ray cholangiography. This trial compared fluorescence and X-ray cholangiography for visualization of the critical junction between the cystic, common hepatic and common bile ducts. METHODS: This non-inferiority blinded RCT included patients who had either intraoperative fluorescence cholangiography using 0·05 mg/kg indocyanine green or X-ray cholangiography during elective laparoscopic cholecystectomy. RESULTS: Between March 2015 and August 2018, a total of 120 patients were randomized (60 in each group). There were no drop-outs and 30-day follow-up data were available for all patients. In intention-to-treat analysis, there was no difference between the fluorescence and X-ray cholangiography groups in ability to visualize the critical junction (49 of 60 versus 51 of 60 respectively; P = 0·230). Fluorescence cholangiography was faster by a few minutes: median 2·0 (range 0·5-5·0) versus 4·8 (1·3-17·6) min (P < 0·001). CONCLUSION: Fluorescence cholangiography was confirmed to be non-inferior to X-ray cholangiography in visualizing the critical junction during laparoscopic cholecystectomy. Registration number: NCT02344654 ( http://www.clinicaltrials.gov).


ANTECEDENTES: La práctica de una colecistectomía laparoscópica segura puede requerir imágenes de la vía biliar, en las cuales la colangiografía con fluorescencia no invasiva puede tener ventajas sobre la colangiografía con contraste con rayos X. Este ensayo comparó la colangiografía con fluorescencia con la colangiografía con rayos X para la visualización de la unión crítica entre el conducto cístico, el conducto hepático común y los conductos biliares comunes. MÉTODOS: Ensayo clínico aleatorizado, ciego, de no inferioridad que incluyó a 120 pacientes en los que durante la colecistectomía laparoscópica electiva se practicó una colangiografía con fluorescencia intraoperatoria utilizando 0,05 mg/kg de verde de indocianina o una colangiografía con rayos X. RESULTADOS: De marzo de 2015 a agosto de 2018, se aleatorizaron un total de 120 pacientes (6 en cada grupo), en los que no hubo abandonos y con datos de seguimiento de 30 días disponibles en todos ellos. Basado en un análisis por intención de tratamiento, la capacidad de visualizar la unión crítica fue igual entre los dos grupos (49/60 versus 51/60, P = 0,23). La colangiografía con fluorescencia fue más rápida de realizar, en unos pocos minutos (mediana 2 min (rango 0,5-5,0) versus 5 min (rango 5,2-17,6), P < 0,001). CONCLUSIÓN: Se confirmó que la colangiografía con fluorescencia no fue inferior a la colangiografía con rayos X para visualizar la unión crítica durante la colecistectomía laparoscópica.


Subject(s)
Cholangiography/methods , Cholecystectomy, Laparoscopic , Elective Surgical Procedures , Intraoperative Care/methods , Optical Imaging/methods , Adult , Aged , Female , Fluorescent Dyes , Follow-Up Studies , Humans , Indocyanine Green , Intention to Treat Analysis , Male , Middle Aged , Outcome Assessment, Health Care , Single-Blind Method
2.
JSLS ; 14(1): 20-2, 2010.
Article in English | MEDLINE | ID: mdl-20412641

ABSTRACT

BACKGROUND: Cystic duct leakage after cholecystectomy is not uncommon and is a potentially serious complication. The aim of this study was to assess a bipolar sealing system (LigaSure) for closure of the cystic duct. METHODS: The records from consecutive laparoscopic cholecystectomies performed in 2 hospitals with closure of the cystic duct with LigaSure after informed consent were recorded and complications and morbidity registered. The records were compared with those of patients undergoing laparoscopic cholecystectomy with closure of the cystic duct with clips during the same period. RESULTS: During the study period, 218 laparoscopic cholecystectomies were performed; 102 of these were performed with the LigaSure. One patient was excluded due to violation of the protocol. We experienced no cases of cystic duct leakage, but in one patient, bile leakage from the gallbladder bed was observed probably due to a small aberrant duct. CONCLUSION: The LigaSure system was safe and effective for closure and division of the cystic duct in laparoscopic cholecystectomy.


Subject(s)
Cholecystectomy, Laparoscopic/instrumentation , Cystic Duct/surgery , Electrocoagulation/methods , Adult , Aged , Electrocoagulation/instrumentation , Female , Humans , Male , Middle Aged , Young Adult
3.
Curr Health Sci J ; 35(1): 5-12, 2009 Jan.
Article in English | MEDLINE | ID: mdl-24778810

ABSTRACT

BACKGROUND AND STUDY AIMS: Exact staging of patients with non-small-cell lung cancer (NSCLC) is important to improve selection of resectable and curable patients for surgery. Positron emission tomography with integrated computed tomography (PET/CT) and endoscopic ultrasound guided fine needle aspiration biopsy (EUS-FNA) are new and promising methods, but indications in lung cancer staging are controversial. Only few studies have compared the 2 methods. The aim of this study was to assess and compare the diagnostic values of PET/CT and EUS-FNA for diagnosing advanced lung cancer in patients, who had both procedures performed. PATIENTS AND METHODS: 27 patients considered to be potential candidates for resection of NSCLC underwent PET/CT and EUS-FNA. Diagnoses were confirmed either by open thoracotomy, mediastinoscopy or clinical follow-up. Advanced lung cancer was defined as tumour-stage ≥ IIIA(N2), corresponding to T4- and/or N2-N3- and/or M1 disease. Diagnostic values of PET/CT and EUS-FNA, with regard to the diagnosis of advanced lung cancer, were assessed and compared. RESULTS: The sensitivity of PET/CT and EUS-FNA were respectively 60% and 60% for T4 disease, 56% versus 100% for N2-N3 disease (p=0.12) and 100% versus 33% for M1 disease (p=0.50). For diagnosing advanced lung cancer PET/CT had a sensitivity of 79%, specificity of 61%, positive predictive value (PPV) of 69%, negative predictive value (NPV) of 73%, and an accuracy of 70%. EUS-FNA had a sensitivity of 79%, specificity of 100%, PPV of 100%, NPV of 81%, and an accuracy of 89% for advanced lung cancer. CONCLUSIONS: PET/CT and EUS-FNA had a comparable sensitivity and NPV for diagnosing advanced lung cancer, but EUS-FNA had superior specificity and PPV. The two methods seem to complement each other.

4.
Endocr Relat Cancer ; 12(3): 599-614, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16172194

ABSTRACT

Development of acquired resistance to antiestrogens is a major clinical problem in endocrine treatment of breast cancer patients. The IGF system plays a profound role in many cancer types, including breast cancer. Thus, overexpression and/or constitutive activation of the IGF-I receptor (IGF-IR) or different components of the IGF-IR signaling pathway have been reported to render breast cancer cells less estrogen dependent and capable of sustaining cell proliferation in the presence of antiestrogens. In this study, growth of the antiestrogen-sensitive human breast cancer cell line MCF-7 was inhibited by treatment with IGF-IR-neutralizing antibodies. In contrast, IGF-IR-neutralizing antibodies had no effect on growth of two different antiestrogen-resistant MCF-7 sublines. A panel of antiestrogen-resistant cell lines was investigated for expression of IGF-IR and either undetectable or severely reduced IGF-IR levels were observed. No increase in insulin receptor substrate 1 (IRS-1) or total PKB/Akt (Akt) was detected in the resistant cell lines. However, a significant increase in phosphorylated Akt (pAkt) was found in four of six antiestrogen-resistant cell lines. Overexpression of pAkt was associated with increased Akt kinase activity in both a tamoxifen- and an ICI 182,780-resistant cell line. Inhibition of Akt phosphorylation by the phosphatidylinositol 3-kinase (PI3-K) inhibitor wortmannin or the Akt inhibitor SH-6 (structurally modified phosphatidyl inositol ether liquid analog PIA 6) resulted in a more pronounced growth inhibitory effect on the antiestrogen-resistant cells compared with the parental cells, suggesting that signaling via Akt is required for antiestrogen-resistant cell growth in at least a subset of our antiestrogen-resistant cell lines. PTEN expression and activity was not decreased in cell lines overexpressing pAkt. Our data demonstrate that Akt is a target for treatment of antiestrogen-resistant breast cancer cell lines and we suggest that antiestrogen-resistant breast cancer patients may benefit from treatment targeted to inhibit Akt signaling.


Subject(s)
Estrogen Receptor Modulators/therapeutic use , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Breast Neoplasms/pathology , Cell Division/drug effects , Cell Line, Tumor , Drug Resistance, Neoplasm , Female , Humans , Protein Serine-Threonine Kinases/drug effects , Proto-Oncogene Proteins/drug effects , Proto-Oncogene Proteins c-akt , Tamoxifen/toxicity
5.
Endoscopy ; 37(9): 833-9, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16116534

ABSTRACT

BACKGROUND AND STUDY AIMS: It would be desirable to develop minimally invasive methods of tissue diagnosis from lymph nodes as well as solid lesions in the mediastinum. The aim of the present study was to test the combined method of transesophageal endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in the evaluation of mediastinal lesions. PATIENTS AND METHODS: EUS-FNA and EBUS-TBNA were compared in 33 patients, for the staging of lung cancer in patients with an established diagnosis of non-small-cell lung cancer (n = 20) or for diagnosis of a suspicious mediastinal lesion in patients with suspected lung cancer (n = 13). EBUS-TBNA and EUS-FNA were unsuccessful in one patient each. The diagnoses were verified in 28 of the remaining 31 patients either at thoracotomy (n = 9) or during the clinical follow-up (n = 19). RESULTS: A total of 119 lesions were sampled by EUS-FNA (n = 59) and EBUS-TBNA (n = 60). EUS-FNA and EBUS-TBNA demonstrated cancer in 26 and 28 lesions, respectively, and benign cytology in 30 and 28 lesions, respectively. Suspicious cells were found in three and four lesions by EUS-FNA and EBUS-TBNA, respectively. When the 60 EBUS-TBNA samples were compared with the 59 EUS-FNA samples, 11 additional cancer diagnoses and three samples with suspicious cells were obtained by EBUS-TBNA that had not been obtained by EUS-FNA. Conversely, EUS-FNA diagnosed 12 additional cancer diagnoses, one suspicious and one specific benign diagnosis (sarcoidosis) in addition to EBUS-TBNA. With a combined approach (EUS-FNA + EBUS-TBNA) in 28 of the 31 patients in whom a final diagnosis was obtained in the evaluation of mediastinal cancer, 20 patients were found to have mediastinal involvement, whereas no mediastinal metastases were found in eight patients. The accuracy of EUS-FNA and EBUS-TBNA, in combination, for the diagnosis of mediastinal cancer was 100 % (95 % CI, 83 - 100 %). CONCLUSIONS: EUS-FNA and EBUS-TBNA appear to be complementary methods. A combined approach with both EUS-FNA and EBUS-TBNA may be able to replace more invasive methods for evaluating lung cancer patients with suspected hilar or mediastinal metastases, as well as for evaluating unclear mediastinal or hilar lesions.


Subject(s)
Biopsy, Fine-Needle/methods , Carcinoma, Non-Small-Cell Lung/pathology , Endosonography , Lung Neoplasms/pathology , Mediastinal Neoplasms/pathology , Mediastinal Neoplasms/secondary , Adult , Aged , Bronchi , Esophagus , Female , Humans , Male , Middle Aged , Neoplasm Staging/methods
7.
Thorax ; 58(12): 1083-6, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14645981

ABSTRACT

BACKGROUND: The aim of the present study was to gain experience with a new method of endoscopic transbronchial ultrasonography with direct, real time guided fine needle aspiration biopsy (EBUS-FNA). METHODS: EBUS-FNA was performed in 11 patients. Selection of the patients for EBUS-FNA was based on computed tomographic (CT) scanning in 10 patients and on positron emission tomography in one. The ultrasonic bronchoscope used was a prototype with an outer diameter of 6.9 mm. The instrument has a small curved array transducer located in front of a 30 degrees oblique forward viewing optic lens and a biopsy channel of 2 mm. The procedures were performed under general anaesthesia. EBUS-FNA was performed by direct transducer contact with the trachea or main bronchi with a prototype 22 gauge needle. RESULTS: A total of 15 lesions were punctured. No complications were experienced. Four lesions were targeted in region 10L, four in region 10R, one in region 4L, three in region 4R, one in region 1, one in region 7, and one in region 2R. The size of the lesions ranged from 7 mm to 80 mm. EBUS-FNA identified malignant cells in 13 lesions and benign cells in two. CONCLUSIONS: EBUS-FNA is a promising technique for lymph node staging of lung cancer as well as for the primary diagnosis of solid lesions located adjacent to the trachea and main bronchi and not accessible by other methods apart from surgical intervention.


Subject(s)
Lung Neoplasms/pathology , Lymph Nodes/pathology , Lymphatic Metastasis/pathology , Adult , Aged , Biopsy, Needle/methods , Endosonography/methods , Female , Humans , Lung Neoplasms/diagnostic imaging , Lymph Nodes/diagnostic imaging , Lymphatic Metastasis/diagnostic imaging , Male , Mediastinal Neoplasms/diagnostic imaging , Mediastinal Neoplasms/secondary , Middle Aged , Ultrasonography, Interventional/methods
8.
Thorax ; 57(2): 98-103, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11828036

ABSTRACT

BACKGROUND: A study was undertaken to evaluate the clinical impact of endoscopic ultrasound guided fine needle aspiration biopsy (EUS-FNA) in patients with mediastinal masses suspected of malignancy. METHODS: From April 1993 to December 1999, 84 patients were referred for EUS-FNA. In all patients CT scanning had shown a lesion of the mediastinum suspected of malignancy located adjacent to the oesophagus. In order to evaluate the clinical impact of EUS-FNA, the history of each patient up to referral for EUS-FNA was reviewed. A board of thoracic specialists was asked to decide the further course of the patient if EUS-FNA had not been available, and this diagnostic strategy was compared with the actual clinical course after EUS-FNA. RESULTS: For the 79 patients in whom sufficient verification was obtained, EUS-FNA had a sensitivity of 92%, specificity of 100%, PPV of 100%, NPV of 80%, and an accuracy of 94% for cancer of the mediastinum. In 18 of 37 patients (49%) a thoracotomy/thoracoscopy was avoided as a result of EUS-FNA, and in 28 of 41 patients (68%) a mediastinoscopy was avoided. The direct result of the cytological diagnosis obtained by EUS-FNA was that a final diagnosis of small cell lung cancer was made in eight patients resulting in referral for chemotherapy, and in another three patients with benign disease specific treatment could be initiated (sarcoidosis, mediastinal abscess, and leiomyoma of the oesophagus). CONCLUSIONS: EUS-FNA is a safe and sensitive minimally invasive method for evaluating patients with a solid lesion of the mediastinum suspected by CT scanning. EUS-FNA has a significant impact on patient management and should be considered for diagnosing the spread of cancer to the mediastinum in patients with lung cancer considered for surgery, as well as for the primary diagnosis of solid lesions located in the mediastinum adjacent to the oesophagus.


Subject(s)
Biopsy, Needle/methods , Endosonography/methods , Mediastinal Neoplasms/diagnostic imaging , Adult , Aged , Aged, 80 and over , Disease Progression , Female , Humans , Lymphatic Metastasis , Male , Middle Aged , Prognosis , Sensitivity and Specificity , Tomography, X-Ray Computed/methods , Ultrasonography, Interventional
9.
Br J Cancer ; 84(5): 686-90, 2001 Mar 02.
Article in English | MEDLINE | ID: mdl-11237391

ABSTRACT

Most breast cancer patients treated with anti-oestrogens will eventually develop resistance towards treatment. Therefore it is important to find new therapeutic agents effective for treatment of patients relapsing on anti-oestrogen. The vitamin D analogue EB1089 (Seocalcitol(TM)) is a promising new agent for treatment of breast cancer patients with advanced disease, and in this study we show that two different anti-oestrogen-resistant human breast cancer cell lines are more sensitive towards treatment with EB1089, than the parent MCF-7 cell line. The two resistant cell lines both express a lower content of the anti-apoptotic protein Bcl-2, and we suggest that this may explain the higher sensitivity towards EB1089. The importance of Bcl-2 for response to EB1089 is supported by our observation that oestradiol abrogates the effect of EB1089 in cell lines which increase Bcl-2 in response to oestradiol treatment. Overall these results indicate that treatment with Seocalcitol(TM)may prove effective when patients become refractory to anti-oestrogen therapy, and that Bcl-2 may be used as a predictive marker.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Calcitriol/analogs & derivatives , Calcitriol/pharmacology , Drug Resistance , Estrogen Antagonists/pharmacology , Tamoxifen/pharmacology , Cell Division/drug effects , Down-Regulation , Estradiol/pharmacology , Estrogen Receptor alpha , Female , Humans , Proto-Oncogene Proteins c-bcl-2/biosynthesis , Receptors, Estrogen/metabolism , Tumor Cells, Cultured
10.
Scand Cardiovasc J ; 34(5): 511-5, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11191943

ABSTRACT

OBJECTIVE: Our aim was to chart the short-term results of the first 75 of our patients who had undergone first-time aortic valve replacement (AVR) with stentless xenografts. DESIGN: Our study included a complete follow-up (mean/max. 1.5/3.7 years) of the first 75 patients (42 males, 33 females; mean age 74, range 61-84 years) who underwent a first AVR with stentless xenografts. RESULTS: Forty-three percent of patients were in functional class II and 57% in classes III-IV preoperatively. Coronary artery bypass grafting (CABG) was performed in 33 patients. Early mortality (< or = 30 days) was 6.7%, with no significant relation to CABG or age. Crude survival was 81% (95% confidence interval, CI: 71-91 %) at 3 years. Using a multivariate analysis, we identified a low left ventricular ejection fraction as a predictor of early and late mortality. Late survival (early mortality excluded) was comparable with the survival of a matched Danish background population. There were six embolic events (all cerebral: 3 minor, 1 major, 2 fatal), while two patients underwent redo-AVR because of either endocarditis (fatal) or aortic regurgitation caused by malaligned commissures. There were no other valve-related complications. Cumulative freedom was 89% (95% CI: 79-99%) for embolism and 86% (95% CI: 76-96 %) for all complications at 3 years. At the end of the study, 64% of the survivors were in functional class I, 34% were in class II and 2% in class III. CONCLUSIONS: Considering the age composition of our patients, and compared with international results, our early mortality rates were acceptable. The absence of late excess mortality compared with the background population and the functional status at end-of-study may indicate the potential haemodynamic advantages of stentless aortic valves, at least in the short term.


Subject(s)
Aortic Valve , Heart Valve Diseases/surgery , Heart Valve Prosthesis , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Postoperative Complications , Survival Analysis , Treatment Outcome
11.
Ugeskr Laeger ; 161(45): 6169-73, 1999 Nov 08.
Article in Danish | MEDLINE | ID: mdl-10603752

ABSTRACT

Over the past 10 years, several studies of neoadjuvant chemotherapy for stage III Non Small Cell Lung Cancer (NSCLC) have been conducted. In eight Phase II studies, response rates of approximately 65% and resectability rates of approximately 50% have been achieved, with acceptable side effects. Two randomized trials with a total of 120 patients with stage IIIA cancer have been carried out to compare the effect of neoadjuvant chemotherapy plus surgery versus surgery alone. The trials were terminated early when interim analysis showed significantly increased survival in groups that received neoadjuvant chemotherapy. The incidences of treatment-related death did not differ significantly between the groups. Neoadjuvant chemotherapy for patients in stage III NSCLC is feasible and might prolong survival. However, the results of larger randomized trials must be awaited before firm general recommendations can be made.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Chemotherapy, Adjuvant/methods , Lung Neoplasms/drug therapy , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/surgery , Humans , Lung Neoplasms/pathology , Lung Neoplasms/surgery , Neoplasm Staging , Prognosis , Randomized Controlled Trials as Topic , Survival Rate
12.
Breast Cancer Res Treat ; 58(1): 41-56, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10634517

ABSTRACT

Development of acquired resistance against antiestrogen treatment is a serious problem in human breast cancer, and knowledge of alterations resulting in resistance is important for selection of further treatment. To mimic the clinical situation we have established a series of MCF-7 human breast cancer cell lines by long term treatment with the antiestrogens tamoxifen, ICI 164,384, and ICI 182,780. Common for these cell lines is a decreased expression of the estrogen receptor alpha (ER alpha). In human breast cancer, lack of response to endocrine therapy is often associated with decreased expression of the estrogen receptor and increased expression of epidermal growth factor receptor (EGFR) and/or HER-2/neu (ErbB-2). Our antiestrogen resistant cell lines did not express altered levels of EGFR, HER-2/neu, ErbB-3, or ErbB-4. Estrogen and antiestrogen regulation of HER-2/neu expression was essentially similar in parent and resistant MCF-7 cells. Treatment with antibodies to HER-2/neu (Herceptin) did not affect growth of MCF-7 cells or resistant cells, indicating that in this in vitro model system, acquired antiestrogen resistance does not emerge from activation of the HER-2/neu signaling pathway. In MCF-7 cells transfected with HER-2/neu and/or ErbB-3, overexpression alone did not result in resistance. However, addition of heregulinl-beta1 abolished the inhibitory activity of ICI 182,780 on both vector and HER-2/neu/ErbB-3 transfected MCF-7 cells, demonstrating that activation of the HER-2/neu receptor signaling pathway can override the growth inhibitory effect of ICI 182,780.


Subject(s)
Breast Neoplasms/metabolism , Estrogen Antagonists/pharmacology , Receptor, ErbB-2/metabolism , Blotting, Northern , Blotting, Western , Breast Neoplasms/genetics , DNA Primers , Drug Resistance, Neoplasm , Enzyme-Linked Immunosorbent Assay , Estradiol/analogs & derivatives , Estradiol/pharmacology , Female , Fulvestrant , Gene Expression Regulation, Neoplastic , Humans , Polyunsaturated Alkamides , Reverse Transcriptase Polymerase Chain Reaction , Tamoxifen/pharmacology , Tumor Cells, Cultured/drug effects
13.
Eur Surg Res ; 31(6): 491-6, 1999.
Article in English | MEDLINE | ID: mdl-10861345

ABSTRACT

It is crucial for the surgeon to know the physical properties of a surgical sealant. Current test methods of fibrin sealant involving animal testing or in vitro testing of sealant using artificial substrates have little clinical relevance. Most of these test methods also lack accuracy and reproducibility. A new model was developed for testing strength and in vitro adhesion of fibrin sealant to vital human tissue using fresh vein leftover from coronary artery bypass grafting. The vein leftover was cut into samples and fastened in a tensiometer linked to a computer. Patient-derived fibrin sealant (0.1 ml) was applied to the tissue, and the surfaces of the tissue samples were held together for 5 min, and then automatically pulled apart by the tensiometer. Data were generated in a load cell and recorded and analysed by the computer. The reproducibility for the adhesion strength was 6.6%, adhesion energy 9.8%, and elongation at break 8.4%. The method has been considered ethical and has good reproducibility. The method can be used for standardised measurements and comparison of different types of fibrin sealant without the sacrifice of animals.


Subject(s)
Fibrin Tissue Adhesive/chemistry , Models, Theoretical , Adhesiveness , Elasticity , Humans , Reproducibility of Results , Tensile Strength
14.
Int J Cancer ; 72(6): 1129-36, 1997 Sep 17.
Article in English | MEDLINE | ID: mdl-9378550

ABSTRACT

To elucidate the mechanisms responsible for the development of anti-estrogen resistance, we have cloned and established 3 stable ICI-182,780-resistant sub-lines, MCF-7/182R-1, MCF-7/182R-6 and MCF-7/182R-7 from the estrogen-receptor(ER)-positive and estrogen-responsive human breast-cancer MCF-7 cell line by long-term treatment with 10(-7) M ICI 182,780. The ICI-182,780-resistant MCF-7 sub-lines express ER, but compared with MCF-7 cells the level is significantly lower in all 3 sub-lines. In the MCF-7 cell line we find that ER expression is regulated by estrogen and anti-estrogens at the transcriptional and post-transcriptional level. This is in contrast to the ICI-182,780-resistant sub-lines, in which we find very little hormonal effects on the ER mRNA expression level. The resistant sub-lines also deviate from parent characteristics by the complete lack of expression of progesterone receptor even when grown in the presence of estradiol. All 3 resistant sub-lines have a lower basal expression of cathepsin-D mRNA comparable with the lower ER expression, but, in contrast, they have higher basal expression of the pS2 mRNA than the parent MCF-7 cell line. Although there are different basal expression levels of the pS2 and cathepsin-D genes, the resistant sub-lines behave like the parent MCF-7 cell line with respect to the hormonal regulation of both genes. The estrogen receptors in the resistant sub-lines have also maintained wild-type characteristics with respect to estrogen and anti-estrogen regulation of the estrogen-regulated proteins procathepsin D, alpha1-antitrypsin and a 42-kDa protein. The resistant cells require estrogen for growth in athymic nude mice. Our results clearly demonstrate that the ER in the resistant sub-lines have a normal function for most parameters investigated, supporting our earlier observation that only wild-type ER protein is expressed in these cells. The few observed differences in ER function between the parent MCF-7 cell line and the resistant sub-lines are not likely to be responsible for the ICI-182,780-resistant phenotype.


Subject(s)
Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Drug Resistance, Neoplasm , Estradiol/analogs & derivatives , Receptors, Estrogen/biosynthesis , Transcription, Genetic/drug effects , Animals , Antineoplastic Agents/toxicity , Breast Neoplasms/chemistry , Cell Nucleus/chemistry , Estradiol/toxicity , Estrogen Antagonists/toxicity , Female , Fulvestrant , Humans , Mice , Mice, Nude , Ovariectomy , RNA, Messenger/biosynthesis , Receptors, Estrogen/analysis , Receptors, Progesterone/analysis , Transplantation, Heterologous , Tumor Cells, Cultured
15.
Cancer Res ; 57(4): 585-9, 1997 Feb 15.
Article in English | MEDLINE | ID: mdl-9044830

ABSTRACT

Development of resistance to tamoxifen is a serious problem in treatment of breast cancer patients. Although the mechanisms for development of resistance are unclear, an altered expression of alternatively spliced estrogen receptor (ER) mRNA has been suggested to be involved. We have looked for differential expression of ER splice variants lacking exon 2 (ERdeltaE2), exon 3 (ERdeltaE3), exon 4 (ERdeltaE4), exon 5 (ERdeltaE5), exon 7 (ERdeltaE7), and exons 4 and 7 (ERdeltaE4, 7) in the human breast cancer cell line MCF-7 and 10 ER-positive MCF-7 sublines resistant to the antiestrogens tamoxifen, ICI 164,384 or ICI 182,780. No major differences in the expression were demonstrated between MCF-7 cells and resistant cells, indicating that ER splice variants are not involved in antiestrogen resistance in this model system. Furthermore, despite a high mRNA level of some of the ER splice variants, no corresponding proteins could be detected using Western blot analysis.


Subject(s)
Breast Neoplasms/genetics , RNA Splicing/genetics , RNA, Messenger/metabolism , RNA, Neoplasm/metabolism , Receptors, Estrogen/genetics , Antineoplastic Agents, Hormonal/pharmacology , Breast Neoplasms/chemistry , Drug Resistance, Neoplasm/genetics , Estradiol/analogs & derivatives , Estradiol/pharmacology , Estrogen Antagonists/pharmacology , Female , Fulvestrant , Genetic Vectors , Humans , Polyunsaturated Alkamides , Receptors, Estrogen/analysis , Tamoxifen/pharmacology , Transfection , Tumor Cells, Cultured/chemistry
16.
Int J Cancer ; 61(4): 529-34, 1995 May 16.
Article in English | MEDLINE | ID: mdl-7759159

ABSTRACT

The pure steroidal anti-estrogens ICI 164,384 and ICI 182,780 are very potent growth inhibitors of the estrogen receptor-positive human breast cancer cell line MCF-7. However, long-term treatment of MCF-7 cells with 10(-7) M concentrations of these compounds results in selection of proliferating colonies of resistant cells. Our report describes 4 ICI 164,384- and 3 ICI 182,780-resistant MCF-7 sublines established after long-term treatment. Resistant sublines are estrogen receptor-positive, and all sublines have lost expression and estrogen inducibility of the progesterone receptor protein. Based on IC50 concentrations, all tested resistant sublines had a reduced sensitivity to pure anti-estrogens on the order of 100- to 1000-fold compared with parent MCF-7 cells. All resistant cell lines have survived propagation for more than 15 subcultivations in the presence of 10(-7) M pure anti-estrogen. The MCF-7/182R-6 subline has been tested for stability of resistance and appeared to be stably resistant after 13 weeks of propagation without the selective pressure of ICI 182,780. Cell lines resistant to the ICI 182,780 compound are cross-resistant to the ICI 164,384 compound and vice versa. However, the sublines resistant to pure antiestrogens are sensitive to tamoxifen. Our results show that although the pure steroidal anti-estrogens are very potent growth inhibitors, they do not circumvent development of resistance.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Estradiol/analogs & derivatives , Estrogen Antagonists/pharmacology , Neoplasms, Hormone-Dependent/drug therapy , Tamoxifen/pharmacology , Animals , Breast Neoplasms/pathology , Breast Neoplasms/ultrastructure , Cell Division/drug effects , Dose-Response Relationship, Drug , Drug Resistance , Drug Screening Assays, Antitumor , Estradiol/pharmacology , Female , Fulvestrant , Humans , Male , Mice , Mice, Nude , Neoplasm Transplantation , Neoplasms, Hormone-Dependent/ultrastructure , Polyunsaturated Alkamides , Receptors, Estrogen/analysis , Receptors, Progesterone/analysis , Tumor Cells, Cultured/drug effects
18.
Sygeplejersken ; 88(16): 22-3, 1988 Apr 20.
Article in Danish | MEDLINE | ID: mdl-3394037
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