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1.
Eur Radiol ; 26(11): 3858-3864, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26920391

RESUMO

PURPOSE: This study evaluates the feasibility of performing less than two core biopsies per MRI-lesion when performing targeted MR-guided in-bore prostate biopsy. METHODS: Retrospectively evaluated were 1545 biopsy cores of 774 intraprostatic lesions (two cores per lesion) in 290 patients (66 ± 7.8 years; median PSA 8.2 ng/ml) regarding prostate cancer (PCa) detection, Gleason score, and tumor infiltration of the first (FBC) compared to the second biopsy core (SBC). Biopsies were acquired under in-bore MR-guidance. RESULTS: For the biopsy cores, 491 were PCa positive, 239 of 774 (31 %) were FBC and 252 of 771 (33 %) were SBC (p = 0.4). Patient PCa detection rate based on the FBC vs. SBC were 46 % vs. 48 % (p = 0.6). For clinically significant PCa (Gleason score ≥4 + 3 = 7) the detection rate was 18 % for both, FBC and SBC (p = 0.9). Six hundred and eighty-seven SBC (89 %) showed no histologic difference. On the lesion level, 40 SBC detected PCa with negative FBC (7.5 %). Twenty SBC showed a Gleason upgrade from 3 + 3 = 6 to ≥3 + 4 = 7 (2.6 %) and 4 to ≥4 + 3 = 7 (0.5 %). CONCLUSION: The benefit of a second targeted biopsy core per suspicious MRI-lesion is likely minor, especially regarding PCa detection rate and significant Gleason upgrading. Therefore, a further reduction of biopsy cores is reasonable when performing a targeted MR-guided in-bore prostate biopsy. KEY POINTS: • Higher PI-RADS overall score (IV-V) correlated well with PCa detection rate • In more than 80 % SBC was concordant regarding overall PCa detection • In almost 90 % there was no Gleason upgrading by the SBC • Only 2/54 (3.7 %) csPCa was missed when the SBC was omitted • For IB-GB a further reduction of biopsy cores is reasonable.


Assuntos
Biópsia com Agulha de Grande Calibre/métodos , Biópsia Guiada por Imagem/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico , Idoso , Humanos , Masculino , Gradação de Tumores , Reprodutibilidade dos Testes , Estudos Retrospectivos
2.
Pathologe ; 36(3): 261-70, 2015 May.
Artigo em Alemão | MEDLINE | ID: mdl-25986886

RESUMO

Neuroendocrine neoplasms (NEN) of the breast are specific tumor entities. According to the literature up to 5% of breast neoplasms are malignant epithelial neoplasms of the breast. They are defined by a neuroendocrine (NE) architecture and cytology combined with an expression of the neuroendocrine vesicle markers chromogranin A and/or synaptophysin. The diagnosis is supplemented by the receptor status and the proliferative activity. According to the World Health Organization (WHO) classification of 2012 the following groups of NEN are distinguished: (1) invasive breast carcinoma with NE differentiation, (2) well-differentiated neuroendocrine tumor (NET) and (3) poorly differentiated small cell carcinoma (NEC). This review article focuses on (1) the definition and basic principles of diagnostics, (2) the history, nomenclature and WHO classification from 2003 and 2012, (3) the frequency of breast NEN, (4) the hereditary background and functional activity, (5) the expression of receptors and (6) the possible clinical implications. In addition, the first results of a retrospective single center study (n = 465 patients with breast cancer over a time period of 4 years) on the frequency of NEN of the breast at the Breast Center of the University Hospital Düsseldorf are presented. In this study a frequency of 4.5% of NEN was found based on a diagnostic cut-off of > 50% Chromogranin A and/or synaptophysin positive tumor cells.


Assuntos
Neoplasias da Mama/patologia , Tumores Neuroendócrinos/patologia , Biomarcadores Tumorais/análise , Mama/patologia , Proliferação de Células , Cromogranina A/análise , Feminino , Humanos , Invasividade Neoplásica , Prognóstico , Sinaptofisina/análise
3.
Pathologe ; 35(3): 283-93; quiz 294, 2014 May.
Artigo em Alemão | MEDLINE | ID: mdl-24671468

RESUMO

Neuroendocrine neoplasms (NEN) of the distal jejunum and ileum derive from serotonin-producing enterochromaffin (EC) cells. Due to their low proliferation rate and their infiltrative growth, they are often discovered at an advanced disease stage when metastasis has already occurred. The biology of these tumours is different from other NEN of the digestive tract. In order to standardise and improve diagnosis and therapy, the guidelines for the diagnosis and clinical management of jejuno-ileal NEN as well as for the management of patients with liver and other distant metastases from NEN were revised by the European Neuroendocrine Tumour Society (ENETS) in 2012. This review focuses on aspects relevant for surgical pathology.


Assuntos
Neoplasias do Íleo/patologia , Neoplasias do Jejuno/patologia , Tumores Neuroendócrinos/patologia , Proliferação de Células , Diagnóstico Diferencial , Progressão da Doença , Células Enterocromafins/patologia , Humanos , Neoplasias do Íleo/cirurgia , Íleo/patologia , Íleo/cirurgia , Neoplasias do Jejuno/cirurgia , Jejuno/patologia , Jejuno/cirurgia , Tumores Neuroendócrinos/cirurgia , Guias de Prática Clínica como Assunto , Receptores de Somatostatina/análise
4.
Endoscopy ; 42(4): 300-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20306384

RESUMO

STUDY AIM: To assess the accuracy of ultrasound-guided fine-needle aspiration biopsy in the differential diagnosis of gastrointestinal stroma cell tumors (GIST) from other submucosal tumors, using both cytology and histology. PATIENTS AND METHODS: We conducted a prospective study from May 2005 to September 2008 in all patients presenting with upper gastrointestinal submucosal tumors. Only patients in whom surgical resection was carried out were included in the final analysis. In cases of mesenchymal tumor, immunocytochemistry was attempted for further differentiation between GIST and non-GIST. Surgical histopathology served as the gold standard. RESULTS: A total of 47 patients were analyzable, with a final histologic diagnosis of 35 mesenchymal tumors. Sufficient tissue for conventional cytologic diagnosis was obtained only in the 35 patients with mesenchymal tumors; in this subgroup, immunocytochemistry was possible in 46 %. If and only if enough material was available for immunocytochemistry, the sensitivity for (correct recognition of) GIST tumors was 93 %. In all 12 patients with nonmesenchymal tumors and lesions, cytology was nondiagnostic and the diagnosis had to be based on clinical suspicion and the appearance on endoscopy and endoscopic ultrasound (EUS). On an intention-to-diagnose basis, endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) had a positive predictive value for mesenchymal tumors of 100 %, but no value for the diagnosis of other lesions; using immunocytochemistry, a GIST tumor was recognized among the mesenchymal tumors with a sensitivity of 58 % and a specificity of 8 %. CONCLUSIONS: EUS-FNA-based cytology is safe and has only limited value for the differential diagnosis of submucosal tumors, mainly because insufficient material is harvested. Better tissue acquisition techniques are necessary for better differential diagnosis.


Assuntos
Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Criança , Pré-Escolar , Diagnóstico Diferencial , Endossonografia , Feminino , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/cirurgia , Tumores do Estroma Gastrointestinal/diagnóstico , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Mucosa Intestinal , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Adulto Jovem
5.
J Cell Biol ; 118(4): 877-87, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1323566

RESUMO

Two clonal rat rhabdomyosarcoma cell lines BA-Han-1B and BA-Han-1C with different capacities for myogenic differentiation have been examined for the expression of muscle regulatory basic helix-loop-helix (bHLH) proteins of the MyoD family. Whereas cells of the BA-Han-1C subpopulation constitutively expressed MyoD1 and could be induced to differentiate with retinoic acid (RA), BA-Han-1B cells did not express any of the myogenic control factors and appeared to be largely differentiation-defective. Upon induction with RA, BA-Han-1C cells expressed also myogenin, in contrast to BA-Han-1B cells which never activated any of the genes encoding muscle bHLH factors. The onset of myogenin transcription in BA-Han-1C cells required de novo protein synthesis and DNA replication suggesting that RA probably did not act directly on the myogenin gene. Although MyoD1 was expressed in proliferating BA-Han-1C myoblasts, muscle-specific reporter genes were not activated indicating that MyoD was biologically inactive. However, transfections with plasmid expressing additional MyoD1 protein resulted in the transactivation of muscle genes even in the absence of RA. mRNA encoding the negative regulatory HLH protein Id was expressed in proliferating BA-Han-1C cells and disappeared later after RA induction which suggested that it may be involved in the regulation of MyoD1 activity. The myogenic differentiation of malignant rhabdomyosarcoma cells strictly correlated with the activation of the myogenin gene. In fact, stable transfections of BA-Han-1C cells with myogenin expressing plasmids resulted in spontaneous differentiation. Together, our results suggest that the transformed and undifferentiated phenotype of BA-Han-1C rhabdomyosarcoma cells is associated with the inactivation of the myogenic factor MyoD1 as well as lack of myogenin expression. RA alleviates the inhibition of myogenic differentiation, probably by activating MyoD protein and myogenin gene transcription. BA-Han-1B cells did not respond to RA and the differentiated phenotype could not be restored by overexpression of MyoD1 or myogenin.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Proteínas Musculares/biossíntese , Músculos/efeitos dos fármacos , Proteínas Repressoras , Fatores de Transcrição/biossíntese , Tretinoína/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , DNA/biossíntese , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína 1 Inibidora de Diferenciação , Proteínas Musculares/genética , Músculos/citologia , Proteína MyoD , Miogenina , Biossíntese de Proteínas , Ratos , Fatores de Transcrição/genética , Células Tumorais Cultivadas
7.
J Cancer Res Clin Oncol ; 134(10): 1071-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18392850

RESUMO

OBJECTIVES: Due to PSA screening and increased awareness, prostate cancer (PCa) is identified earlier resulting in smaller diagnostic samples on prostate needle biopsy. Because Gleason grading plays a critical role in treatment planning, we undertook a controlled study to evaluate interobserver variability among German pathologists to grade small PCas using a series of tissue microarray (TMA) images. METHODS: We have previously demonstrated excellent agreement in Gleason grading using TMAs among expert genitourinary pathologists. In the current study, we identified 331 TMA images (95% PCa and 5% benign) to be evaluated by an expert PCa pathologist and subsequently by practicing pathologists throughout Germany. The images were presented using the Bacus Webslide Browser on a CD-ROM. Evaluations were kept anonymous and participant's scoring was compared to the expert's results. RESULTS: A total of 29 German pathologists analysed an average of 278 images. Mean percentage of TMA images which had been assigned the same Gleason score (GS) as done by the expert was 45.7%. GSs differed by no more than one point (+/-1) in 83.5% of the TMA samples evaluated. The respondents were able to correctly assign a GS into clinically relevant categories (i.e. <7, 7, >7) in 68.3% of cases. A total of 75.9% respondents under-graded the TMA images. Gleason grading agreement with the expert reviewer correlated with the number of biopsies evaluated by the pathologist per week. Years of diagnostic experience, self-description as a urologic pathologist or affiliation with a university hospital did not correlate with the pathologist's performance. CONCLUSION: The vast majority of participants under-graded the small tumors. Clinically relevant GS categories were correctly assigned in 68% of cases. This raises a potentially significant problem for pathologists, who have not had as much experience evaluating small PCas.


Assuntos
Patologia Cirúrgica/normas , Neoplasias da Próstata/patologia , Análise Serial de Tecidos , Biópsia por Agulha , Alemanha , Humanos , Masculino , Variações Dependentes do Observador , Neoplasias da Próstata/epidemiologia , Reprodutibilidade dos Testes
8.
Endocr Relat Cancer ; 14(2): 245-56, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17639041

RESUMO

Rac proteins of the Rho-like GTPase family, including the ubiquitous Rac1, the hematopoiesis-specific Rac2, and the least-characterized Rac3 play a major role in oncogenic transformation, tumor invasion and metastasis. However, the prognostic relevance of Rac expression in human tumors has not been investigated yet. In the present study, Rac protein expression was analyzed in benign secretory epithelium, high-grade prostatic intraepithelium neoplasia (HG-PIN), and prostate carcinomas of 60 R0-resected radical prostatectomy specimens by semiquantitative immunohistochemistry. Thus, Rac proteins were significantly strongly expressed in HG-PIN (P < 0.001) and prostate carcinomas (P < 0.001) when compared with benign secretory epithelium. Accordingly, all tumor tissues analyzed by isoform-specific real-time PCR (n = 7) exhibited significantly higher RNA expression levels of Rac (i.e. sum of Rac1 and Rac3 expression levels) than the respective benign counterparts (P = 0.018) and this appeared to result mainly from increased expression of the Rac3 isoform as verified by immunoblotting. Univariate analyses showed statistically significant associations of increased Rac protein expression in prostate cancer (P = 0.045), preoperative prostate-specific antigen levels (P = 0.044), pT stage (P = 0.002), and Gleason score (P = 0.001) with decreased disease-free survival (DFS). This prognostic effect of increased protein expression of Rac remained significant even in a multivariate analysis including all these four factors (relative risk = 3.22, 95% confidence interval = 1.04-10.00; P = 0.043). In conclusion, our data suggest that increased Rac protein expression in prostate cancer relative to the corresponding benign secretory epithelium is an independent predictor of decreased DFS and appears to result mainly from increased expression of the Rac3 isoform.


Assuntos
Carcinoma/diagnóstico , Neoplasias da Próstata/diagnóstico , Proteínas rac de Ligação ao GTP/análise , Proteínas rac1 de Ligação ao GTP/análise , Idoso , Carcinoma/patologia , Carcinoma/cirurgia , Intervalo Livre de Doença , Humanos , Immunoblotting , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Isoformas de Proteínas/análise , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Proteínas rac de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/genética
9.
J Cancer Res Clin Oncol ; 133(10): 749-59, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17530287

RESUMO

Only few clinical factors predict the prognosis of patients with Ewing tumors. Unfavorable outcome is associated with primary metastatic disease, age > 15 years, tumor volume above 200 ml, and the histological response to chemotherapy. The aim of this study was to elucidate the prevalence and clinical impact of microsatellite instability (MSI) together with the relation between MSI and mismatch repair protein expression in Ewing tumors. DNA from 61 primary Ewing tumors and 11 Ewing tumor cell lines was extracted and microsatellite analysis for the detection of instability or loss of heterozygosity was performed for the five markers of the Bethesda panel BAT25, BAT26, D5S346, D2S123, and D17S250, which represents the established marker panel for the analysis of hereditary non-polyposis colorectal carcinoma (HNPCC) patients. In addition, single nucleotide repeat regions of the two tumor genes BAX and transforming growth factor receptor II (TGFBR2) were also included. All of the 61 samples were suitable for LOH analysis and 55 for the determination of MSI-status. LOH of these microsatellite markers was detected in 9 of the 61 patients (14.8%). Over all, genetic instability, i.e. MSI and/or LOH, was detected in 17 tumors (27.9%). One out of the 11 tumor cell lines (STA ET1) was characterized by instability of all the five Bethesda markers, while from primary tumor samples, only one showed MSI in more than one microsatellite marker (D5S346 and D17S250, MSI-high). Eight of the fifty-five patients (14.5%) showed instability of one microsatellite locus (MSI-low). No instability was detected in BAT26, D2S123, BAX and TGFBR2. There was no significant correlation between MSI and loss of expression of mismatch repair proteins MLH1, MSH2, or MSH6. The impairment of the p53 signaling pathway (expression of TP53 and/or MDM2 by immunohistochemistry) was significantly associated with reduced overall survival (15 of 49 patients (30.6%), P = 0.0410, log-rank test). We conclude that MSI is not prevalent in Ewing tumor and that the nature of instability differs from the form observed in colorectal carcinoma, the model tumor of MSI. This is documented by the different pattern of MSI (no BAT26 instability) in Ewing tumors and the lack of a strict correlation between MSI-high and loss of expression of MSH2, MSH6 and MLH1.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Instabilidade de Microssatélites , Proteína 2 Homóloga a MutS/biossíntese , Proteínas Nucleares/biossíntese , Sarcoma de Ewing/genética , Sarcoma de Ewing/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , Análise Mutacional de DNA , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Perda de Heterozigosidade , Proteína 1 Homóloga a MutL , Proteínas de Fusão Oncogênica/biossíntese , Reação em Cadeia da Polimerase , Proteína Proto-Oncogênica c-fli-1 , Proteína EWS de Ligação a RNA , Sarcoma de Ewing/mortalidade , Análise de Sobrevida , Fatores de Transcrição/biossíntese , Proteína Supressora de Tumor p53/biossíntese
11.
Cancer Res ; 59(24): 6097-102, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10626797

RESUMO

Recently, a novel antiapoptosis gene, i.e., survivin, was identified as a structurally unique member of the inhibitor of apoptosis protein family. Survivin expression is turned off during fetal development and not found in non-neoplastic adult human tissues but is again turned on in the most common human cancers. The antiapoptotic properties of survivin might provide a significant growth advantage in tumors and possibly also contribute to chemoresistance of cancer. Therefore, we analyzed the expression of survivin in human renal cell carcinomas (RCCs), known to be largely resistant to chemotherapy. Northern blot analysis and RT-PCR revealed survivin expression in newly established RCC cell lines (n = 11) of all major histological types. Moreover, we identified two novel splice variants of survivin, lacking exon 3 (survivin-deltaEx3) or retaining a part of intron 2 as a cryptic exon (survivin-2B). Both sequence alterations cause marked changes in the structure of the corresponding proteins, including structural modifications of the baculovirus inhibitor of apoptosis protein repeat domain. The role of the novel isoforms in the regulation of apoptosis was assessed in transfection experiments, showing conservation of antiapoptotic properties for survivin-deltaEx3 and a markedly reduced antiapoptotic potential for survivin-2B. In conclusion, our observations suggest a complex regulatory balance between the different isoforms of survivin, which might determine the response to proapoptotic stimuli, not only in human RCCs but also in fetal tissues and other types of cancer.


Assuntos
Processamento Alternativo , Apoptose , Proteínas Associadas aos Microtúbulos , Proteínas/genética , Sequência de Aminoácidos , Sequência de Bases , Carcinoma de Células Renais/metabolismo , DNA de Neoplasias , Humanos , Proteínas Inibidoras de Apoptose , Neoplasias Renais/metabolismo , Dados de Sequência Molecular , Proteínas de Neoplasias , Biossíntese de Proteínas , Conformação Proteica , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Proteínas/química , Proteínas/fisiologia , Homologia de Sequência de Aminoácidos , Survivina , Células Tumorais Cultivadas
12.
Cancer Res ; 48(18): 5264-9, 1988 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-3409249

RESUMO

BA-HAN-1C is a clonal rat rhabdomyosarcoma cell line composed of proliferating mononuclear cells, which partly fuse to terminally differentiated postmitotic myotube-like giant cells. The exposure to retinoic acid in vitro resulted in time- and dose-dependent changes of both cell differentiation and cell growth. The mononuclear cells revealed bundles of newly formed thick and thin myofilaments, never observed in untreated cultures, and exhibited signs of contact inhibition. In addition, there was a statistically significant increase (P less than 0.001) in the number of terminally differentiated postmitotic myotube-like giant cells and in the creatine kinase activity (P less than 0.05) which was used as a biochemical differentiation marker. At the same time cell growth was significantly inhibited (P less than 0.001) in vitro and a decrease in plating efficiency, as well as in saturation density, was observed. These data demonstrate that retinoic acid can suppress cell growth and simultaneously initiate differentiation in a malignant mesenchymal tumor cell line. However, despite the clonal nature of BA-HAN-1C, the complete status of terminal differentiation was not achieved by all tumor cells. The reason why not all tumor cells responded to retinoic acid is unknown at the present time and will have to be the subject of further studies.


Assuntos
Rabdomiossarcoma/patologia , Tretinoína/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Fusão Celular , Linhagem Celular , Creatina Quinase/metabolismo , Microscopia Eletrônica , Ratos
13.
Cancer Res ; 46(10): 5320-9, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3756881

RESUMO

Oxygenation and development of necrosis were evaluated in multicellular spheroids of poorly differentiated (HT29) and moderately well-differentiated (Co112) human adenocarcinoma of the colon. Spheroids were grown in vitro under well-controlled oxygen and nutrient conditions in spinner flasks up to sizes of 2800-micron diameter after 5 wk of culture. Morphological studies showed that the Co112 spheroids contained pseudoglandular structures with lumen, very similar to the characteristics of the original tumor specimen from the patient and to the cells when grown as xenograft tumors in nude mice. Microelectrodes were used to measure the oxygen tension (PO2) profile within individual spheroids at different stages of growth. Histological sections through the centers of spheroids were measured to determine the thickness of the viable rim of cells surrounding spheroid necrotic centers in order to estimate the size of the severely hypoxic zone of cells by comparison with the PO2 profiles of the same spheroids. The data demonstrate significant differences between these two human colon tumor spheroid systems. Both spheroid types exhibited steep PO2 gradients at relatively small sizes of less than 600-micron diameter, but for any given size in this range, the more differentiated Co112 spheroids were more hypoxic. Although severe hypoxia (PO2, less than 10 mm of Hg) was present in both spheroid types at larger sizes, there was a significant difference in the central PO2 values which were between 5 and 10 mm of Hg in large Co112 spheroids but remained at or close to 0 mm of Hg in large HT29 poorly differentiated human colon tumor spheroids. The presence of pseudoglandular structures and lumen in the Co112 spheroids was associated with changes in the shape of PO2 profiles. Such profiles have not previously been seen in other poorly differentiated human or rodent tumor spheroids. Furthermore, the PO2 profiles of both of these human tumor spheroid types were often continuously curving with a very shallow gradient in the inner edge of the viable rim of cells surrounding the necrotic center. Regulation of oxygen consumption and/or diffusion in these inner regions of human spheroids could produce these continuously curving PO2 gradients.


Assuntos
Adenocarcinoma/ultraestrutura , Neoplasias do Colo/ultraestrutura , Oxigênio/análise , Adenocarcinoma/metabolismo , Diferenciação Celular , Células Cultivadas , Neoplasias do Colo/metabolismo , Humanos , Consumo de Oxigênio , Pressão Parcial
14.
Cancer Res ; 52(2): 474-7, 1992 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1728419

RESUMO

A novel type of multicellular spheroids was established and characterized with regard to growth behavior, proliferation, and differentiation. The spheroids were grown from clonal rat rhabdomyosarcoma cells using the spinner flask technique. The cell aggregates showed several unique properties that were different from those observed in most of the spheroids investigated to date. These properties include a non-Gompertzian volume growth; the coexistence of undifferentiated mononuclear cells and of differentiated, myotube-like giant cells with numerous nuclei; a relatively homogeneous intraspheroidal distribution of proliferating mononuclear cells with thymidine labeling even in the center of spheroids greater than 1 mm; the absence of necrosis in such large spheroids, and the accumulation of myotube-like cells in the center of these spheroids instead. There was a decrease in the overall proliferative activity of the mononuclear cells with increasing proportion of giant cells in the rhabdomyosarcoma spheroids.


Assuntos
Rabdomiossarcoma/patologia , Animais , Diferenciação Celular , Divisão Celular , Células Clonais , DNA de Neoplasias/biossíntese , Técnicas In Vitro , Organoides , Ratos
15.
Cancer Res ; 49(24 Pt 1): 7132-40, 1989 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-2582454

RESUMO

Three clonal subpopulations (A, B, C) isolated from the same rhabdomyosarcoma of the rat were tested and compared for their susceptibility to differentiation induction using retinoic acid (RA), dimethylformamide (DMF), and N-monomethylformamide (NMF). These subpopulations differ in that a block to spontaneous differentiation is imposed at different stages which are characteristic for each subpopulation. Whereas tumor cell proliferation was significantly inhibited (P less than 0.001) in all three subpopulations, the effects of RA, DMF, and NMF on tumor cell differentiation were strikingly heterogeneous. The response was most marked in subpopulation C, as evidenced by a significant increase in the number of terminally differentiated myotube-like giant cells (P less than 0.001) and in biochemical differentiation, as indicated by the creatine kinase activity (P less than 0.05). Between 5% (DMF and NMF) and 30% (RA) of the mononuclear cells in subpopulation C exhibited thick and thin myofilaments, which were never observed in the mononuclear cells of the control. In contrast, subpopulation A and B responded to RA, DMF, and NMF quite heterogeneously with an increase in biochemical differentiation, whereas terminally differentiated myotube-like giant cells were never observed. These results demonstrate that the therapeutic potential of differentiation induction in malignant tumors may be impaired by tumor heterogeneity.


Assuntos
Dimetilformamida/farmacologia , Formamidas/farmacologia , Rabdomiossarcoma/patologia , Tretinoína/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Fusão Celular/efeitos dos fármacos , Células Clonais , Creatina Quinase/metabolismo , Isoenzimas , Ratos , Células Tumorais Cultivadas
16.
Cancer Res ; 59(1): 198-204, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9892207

RESUMO

On the basis of epidemiological observations that nonsteroidal antiinflammatory drugs reduce the risk of esophageal carcinoma, we studied the expression of cyclooxygenase-2 (COX-2) in esophageal squamous cell carcinomas (SCCs; n = 172) and in esophageal adenocarcinomas (ADCs; n = 27). Using immunohistochemistry, we observed COX-2 expression in 91% of the SCCs and in 78% of the ADCs. Western blot analysis showed enhanced expression of the COX-2 protein in some tumors as compared with normal esophageal squamous epithelium, whereas similar amounts of the COX-1 protein were found in normal and cancerous tissues. COX expression was also studied in two esophageal cancer cell lines (OSC-1 and OSC-2) to evaluate the functional relevance of COX-2-derived prostaglandins (PGs). OSC-2 cells expressed COX-2 but not COX-1, whereas OSC-1 cells expressed high levels of COX-1 but showed only a very weak COX-2 expression. Accordingly, PGE2 synthesis was 600 times higher in the OSC-2 cells as compared with the OSC-1 cells. Treatment of OSC-2 cells with the selective COX-2 inhibitors flosulide and NS-398 concentration dependently suppressed PGE2 synthesis and proliferation and also induced apoptosis. In contrast, no effect of the COX-2 inhibitors was seen in OSC-1 cells. Our data demonstrate that COX-2 is expressed in the majority of esophageal SCCs and ADCs and that COX-2-derived PGs play an important role in the regulation of proliferation and apoptosis of esophageal tumor cells. It is concluded that inhibition of COX-2 may be useful in the therapy of esophageal cancer.


Assuntos
Carcinoma/enzimologia , Neoplasias Esofágicas/enzimologia , Isoenzimas/biossíntese , Prostaglandina-Endoperóxido Sintases/biossíntese , Carcinoma/patologia , Divisão Celular , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Neoplasias Esofágicas/patologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Proteínas de Membrana , Peroxidases/biossíntese , Células Tumorais Cultivadas
17.
Cell Death Differ ; 7(11): 1127-36, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11139287

RESUMO

TRAIL (APO-2L) is a newly identified member of the TNF family and induces apoptosis in cancer cells without affecting most non-neoplastic cells, both in vitro and in vivo. Our study focused on the expression and function of TRAIL and its receptors in renal cell carcinoma (RCC) cell lines of all major histological types. Here, we demonstrate that all RCC cell lines express TRAIL as well as the death-inducing receptors TRAIL-R1 (DR4) and TRAIL-R2 (Killer/DR5). Exposure to TRAIL induced apoptosis in 10 of 16 RCC cell lines. Remarkably, five of six TRAIL-resistant RCC cell lines exhibited high levels of TRAIL expression. Topotecan, a novel topoisomerase I inhibitor, induced upregulation of TRAIL-R2 as well as downregulation of TRAIL. Neutralization of TRAIL with recombinant soluble TRAIL-R1-Fc and TRAIL-R2-Fc failed to inhibit topotecan-induced apoptosis indicating that topotecan-induced cell death can occur in a TRAIL-independent fashion. However, exposure to topotecan resulted in an enhancement of TRAIL-induced apoptosis in all primarily TRAIL-resistant RCC cell lines. This synergistic effect of cotreatment with Topotecan and TRAIL may provide the basis for a new therapeutic approach to induce apoptosis in otherwise unresponsive RCC.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Renais/patologia , Inibidores Enzimáticos/farmacologia , Neoplasias Renais/patologia , Glicoproteínas de Membrana/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Topotecan/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose , Carcinoma de Células Renais/metabolismo , Genes p53 , Humanos , Neoplasias Renais/metabolismo , Glicoproteínas de Membrana/genética , Mutação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ligante Indutor de Apoptose Relacionado a TNF , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
18.
Cell Death Differ ; 9(12): 1334-42, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12478470

RESUMO

Survivin is an inhibitor of apoptosis protein (IAP) that is markedly overexpressed in most cancers. We identified two novel functionally divergent splice variants, i.e. non-antiapoptotic survivin-2B and antiapoptotic survivin-deltaEx3. Because survivin-2B might be a naturally occurring antagonist of antiapoptotic survivin variants, we analyzed the subcellular distribution of these proteins. PSORT II analysis predicted a preferential cytoplasmic localization of survivin and survivin-2B, but a preferential nuclear localization of survivin-deltaEx3. GFP-tagged survivin variants confirmed the predicted subcellular localization and additionally revealed a cell cycle-dependent nuclear accumulation of survivin-deltaEx3. Moreover, a bipartite nuclear localization signal found exclusively in survivin-deltaEx3 may support cytoplasmic clearance of survivin-deltaEx3. In contrast to the known association between survivin and microtubules or centromeres during mitosis, no corresponding co-localization became evident for survivin-deltaEx3 or survivin-2B. In conclusion, our study provided data on a differential subcellular localization of functionally divergent survivin variants, suggesting that survivin isoforms may perform different functions in distinct subcellular compartments and distinct phases of the cell cycle.


Assuntos
Processamento Alternativo/genética , Núcleo Celular/metabolismo , Células Eucarióticas/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Apoptose/genética , Compartimento Celular/genética , Núcleo Celular/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Citoplasma/genética , Citoplasma/metabolismo , Células Eucarióticas/citologia , Proteínas de Fluorescência Verde , Células HeLa , Humanos , Proteínas Inibidoras de Apoptose , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Proteínas Luminescentes , Proteínas Associadas aos Microtúbulos/genética , Dados de Sequência Molecular , Proteínas de Neoplasias , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes de Fusão , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Survivina
19.
Clin Cancer Res ; 3(12 Pt 1): 2263-8, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9815623

RESUMO

In the present study, urokinase-type plasminogen activator (uPA) expression in 150 potentially curatively resected SCCs of the esophagus was analyzed immunohistochemically by means of a murine monoclonal antibody (American Diagnostica, Greenwich, CT) and correlated with survival. Altogether, 122 of the 150 tumors (81.3%) expressed different levels of uPA. Among the 122 uPA-positive tumors, 104 (85.2%) showed a weak staining intensity, and 18 (14.8%) showed a strong staining intensity. Among the uPA-positive tumors, 29 (23. 8%) tumors showed a uPA immunoreactivity in 6-25% of all tumor cells, 30 (24.6%) showed a uPA immunoreactivity in 26-50% of all tumor cells, 41 (33.6%) showed a uPA immunoreactivity in 51-75% of all tumor cells, and 22 (18.0%) showed a uPA immunoreactivity in 76-100% of all tumor cells. No significant correlation could be shown between the different patterns of uPA expression and various clinicopathological parameters, such as pT category, pN category, tumor size, histological grade, blood vessel invasion, lymphatic vessel invasion, and inflammatory response. Concerning the overall postoperative survival, no significant differences between uPA-positive and uPA-negative tumors could be verified. This also held true when different cut points in the percentage of uPA-positive tumor cells were used. In contrast, the intensity of uPA staining provided significant prognostic information in that patients with strongly uPA-positive tumors had a poorer outcome than patients with weakly uPA-positive or uPA-negative tumors. Moreover, as shown by stepwise multivariate Cox regression analysis, the intensity of uPA expression was an independent prognostic factor.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Ativador de Plasminogênio Tipo Uroquinase/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Citoplasma/enzimologia , Citoplasma/patologia , Intervalo Livre de Doença , Neoplasias Esofágicas/enzimologia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/cirurgia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Inflamação , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Ativador de Plasminogênio Tipo Uroquinase/genética
20.
Clin Cancer Res ; 4(3): 577-83, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9533524

RESUMO

Bcl-X, a Bcl-2-related protein, is a potent antagonist of apoptosis in its long splice variant (Bcl-X(L)). The present study was performed to determine its expression in preneoplastic and neoplastic lesions of the esophagus, its correlation with other members of the Bcl-2 family, and its impact on the outcome of surgically treated esophageal cancer patients. Samples of normal esophageal squamous epithelium (n = 10), severe squamous cell dysplasias (n = 19), carcinomas in situ (n = 14), invasive squamous cell carcinomas (n = 172), and lymph node metastases (n = 21) were immunohistochemically analyzed for Bcl-X(L) expression using a polyclonal anti-Bcl-X(L) antibody. The immunostaining was evaluated according to a score system (0-12 points) based on the percentage of positive tumor cells and the relative immunostaining intensity. Cytoplasmic staining for Bcl-X(L) protein was invariably found in all cell layers of the normal esophageal squamous epithelium. In contrast, a considerable portion of preneoplastic and neoplastic lesions display a decreased Bcl-X(L) expression as compared with that in the normal esophageal epithelium. On comparison of the amount of Bcl-X(L) expression between the different types of lesions, however, no significant differences were found between severe squamous cell dysplasias (mean immunoreactive score +/- SD, 5.2 +/- 1.8), carcinomas in situ (5.2 +/- 2.2), invasive carcinomas (4.5 +/- 2.8), and lymph node metastases (4.2 +/- 2.6). In invasive carcinomas, Bcl-X(L) expression decreased continuously with decreasing tumor differentiation (P = 0.0001) and was also directly correlated with bcl-2-associated X protein expression (P = 0.0001). On the contrary, an inverse correlation was found between Bcl-X(L) expression and Bcl-2 protein expression (P = 0.0001). No correlation was found between Bcl-X(L) expression and the parameters pT category, pN category, and tumor size. In the univariate survival analysis, patients with low immunoreactive scores (< or = 4) of Bcl-X(L) expression in the tumor tissue showed lower 2-year and 5-year survival rates than patients with high immunoreactive scores (> 4; P = 0.0485). In multivariate survival analysis, however, only the parameters pN category and pT category, but not Bcl-X(L) expression, could be verified as independent prognostic factors. This tendency of decreasing levels of an antiapoptotic protein toward unfavorable outcome is supported by an increasing number of studies on the role of Bcl-2, another antiapoptotic protein, and must be interpreted against the backdrop of apoptosis as a result of the interaction of many cell death-promoting and protecting proteins.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Lesões Pré-Cancerosas/patologia , Proteínas Proto-Oncogênicas c-bcl-2/análise , Apoptose , Carcinoma in Situ/mortalidade , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/cirurgia , Esôfago/citologia , Esôfago/patologia , Humanos , Imuno-Histoquímica , Metástase Linfática , Mucosa/citologia , Mucosa/patologia , Invasividade Neoplásica , Lesões Pré-Cancerosas/mortalidade , Lesões Pré-Cancerosas/cirurgia , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Valores de Referência , Taxa de Sobrevida , Fatores de Tempo , Proteína bcl-X
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