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1.
Biomedicines ; 11(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36979734

RESUMO

Background and aims: Diagnosis of the biliary stricture remains a challenge. In view of the low sensitivity of brush cytology (BC), fluorescence in situ hybridization (FISH) has been reported as a useful adjunctive test in patients with biliary strictures. We aimed to determine performance characteristics of BC and FISH individually and in combination (BC + FISH) in the primary diagnosis of biliary strictures. Methods: This single-center prospective study was conducted between April 2019 and January 2021. Consecutive patients with unsampled biliary strictures undergoing first endoscopic retrograde cholangiopancreatography in our institution were included. Tissue specimens from two standardized transpapillary brushings from the strictures were examined by routine cytology and FISH. Histopathological confirmation after surgery or 12-month follow-up was regarded as the reference standard for final diagnosis. Results: Of 109 enrolled patients, six were excluded and one lost from the final analysis. In the remaining 102 patients (60.8% males, mean age 67.4, range 25-92 years), the proportions of benign and malignant strictures were 28 (27.5%) and 74 (72.5%), respectively. The proportions of proximal and distal strictures were 26 (25.5%) and 76 (74.5%), respectively. In comparison to BC alone, FISH increased the sensitivity from 36.1% to 50.7% (p = 0.076) while maintaining similar specificity (p = 0.311). Conclusions: Dual-modality tissue evaluation using BC + FISH showed an improving trend in sensitivity for the primary diagnosis of biliary strictures when compared with BC alone.

2.
Klin Onkol ; 32(5): 380-387, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31610672

RESUMO

BACKGROUND: Triple-negative breast cancers (TNBCs) are considered a morphologically heterogeneous group of breast carcinomas characterized by the absence or low protein expression of hormone receptors and HER2/neu/ERBB2 with a specific biological behavior and therapeutic response. This study aimed to evaluate correlations of the density of tumor-infiltrating lymphocytes/plasmocytes (TILs) in the tumor parenchyma, stroma, and invasive margins with tumor morphology, the proliferation rate, Bcl-2 expression, and selected clinical and pathological parameters in early breast cancer patients prior to mastectomy who had not received initial chemotherapy. MATERIALS AND METHODS: Samples of 3,544 breast cancer patients investigated in our department between 2007 and 2017 were re-examined. In total, 413 (11.65%) patients were diagnosed with TNBC. Only 61 cases did not undergo neoadjuvant therapy prior to mastectomy. Correlations between the density of TILs and tumor morphology, Bcl-2 expression, proliferative activity measured by Ki-67, patient age at diagnosis, tumor grade, and metastases were investigated. RESULTS: The samples were predominantly relatively well-localized invasive carcinomas of no special type with medullary features (80.32%) that measured on average 13.4mm (range 5-20mm, median 15mm) and exhibited central necrosis or fibrosis, a tendency to undergo spindle cell and/or apocrine-like differentiation, and intensive infiltration of TILs. There were significant positive correlations between TILs and premenopausal status (p=0.003), Ki-67 expression (p=0.015), and tumor grade (p=0.002), a marginal positive correlation between TILs and tumor size (p=0.065), and a significant negative correlation between TILs and Bcl-2 expression (p=0.035). In younger patients (< 50 years) with tumor size less than or equal to 20 mm (pT1a-pT1c) we recorded a lower number of women with metastatic lymph node involvement (p=0.001). CONCLUSION: The density and location of TILs in non-therapeutically influenced TNBCs, evaluated in the context of morphological changes and other clinicopathological parameters, may have prognostic significance and assist effective therapy planning.


Assuntos
Linfócitos do Interstício Tumoral , Neoplasias de Mama Triplo Negativas , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Antígeno Ki-67/metabolismo , Mastectomia , Pessoa de Meia-Idade , Terapia Neoadjuvante , Gradação de Tumores , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias de Mama Triplo Negativas/imunologia , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia
3.
Prostate ; 79(4): 352-362, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30499118

RESUMO

BACKGROUND: Castration-resistant prostate cancer (PCa) represents a serious health challenge. Based on mechanistically-supported rationale we explored new therapeutic options based on clinically available drugs with anticancer effects, including inhibitors of PARP1 enzyme (PARPi), and histone deacetylases (vorinostat), respectively, and disulfiram (DSF, known as alcohol-abuse drug Antabuse) and its copper-chelating metabolite CuET that inhibit protein turnover. METHODS: Drugs and their combination with ionizing radiation (IR) were tested in various cytotoxicity assays in three human PCa cell lines including radio-resistant stem-cell like derived cells. Mechanistically, DNA damage repair, heat shock and unfolded protein response (UPR) pathways were assessed by immunofluorescence and immunoblotting. RESULTS: We observed enhanced sensitivity to PARPi/IR in PC3 cells consistent with lower homologous recombination (HR) repair. Vorinostat sensitized DU145 cells to PARPi/IR and decreased mutant p53. Vorinostat also impaired HR-mediated DNA repair, as determined by Rad51 foci formation and downregulation of TOPBP1 protein, and overcame radio-resistance of stem-cell like DU145-derived cells. All PCa models responded well to CuET or DSF combined with copper. We demonstrated that DSF interacts with copper in the culture media and forms adequate levels of CuET indicating that DSF/copper and CuET may be considered as comparable treatments. Both DSF/copper and CuET evoked hallmarks of UPR in PCa cells, documented by upregulation of ATF4, CHOP and phospho-eIF2α, with ensuing heat shock response encompassing activation of HSF1 and HSP70. Further enhancing the cytotoxicity of CuET, combination with an inhibitor of the anti-apoptotic protein survivin (YM155, currently undergoing clinical trials) promoted the UPR-induced toxicity, yielding synergistic effects of CuET and YM155. CONCLUSIONS: We propose that targeting genotoxic and proteotoxic stress responses by combinations of available drugs could inspire innovative strategies to treat castration-resistant PCa.


Assuntos
Dissulfiram/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Vorinostat/uso terapêutico , Linhagem Celular Tumoral , Reparo do DNA/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Terapia de Alvo Molecular/métodos , Células PC-3 , PTEN Fosfo-Hidrolase/genética , Tolerância a Radiação , Reparo de DNA por Recombinação/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Proteína Supressora de Tumor p53/genética
4.
Oncol Lett ; 13(6): 4201-4207, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28599421

RESUMO

To date, no comprehensive prognostic or predictive marker profiling analysis has been performed in association with the age of patients with breast cancer. In the present study, 632 breast cancer tissue samples were analyzed for expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), B-cell lymphoma (Bcl)-2 protein, HER2 gene amplification, proliferation [as evaluated by proliferating cell nuclear antigen (PCNA) and Ki-67 index], tumor grade, histological type and molecular subtype. The data revealed correlations with the age of patients. A statistically significant positive correlation was identified between patient age and expression of ER (P<0.0001). There was no significant association between patient age and PR, HER2 protein expression, HER2 gene amplification or PCNA. A significant negative correlation between age and Ki-67 expression (P<0.0001) as well as grade of tumor (P=0.007) was identified. The spectrum of molecular subtypes differed according to age (P=0.0003). The highest incidence of aggressive triple-negative and HER2-positive breast cancer was present in patients aged between 20 and 39 years. Luminal A subtype was the most frequent cancer subtype in patients from age 40 onwards, where proliferation activity declined with age and expression of hormone receptors increased along with Bcl-2 expression. Aggressive forms of breast cancer were more common in younger patients. Prognostic and predictive markers have a complex age-specific distribution. The findings of less aggressive luminal A and B subtypes in older patients, and the positive correlation with ER, PR and Bcl-2 expression reveal the potential efficacy of Bcl-2 as a marker of hormone responsiveness in these patients.

5.
Oncotarget ; 7(32): 52045-52060, 2016 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-27409832

RESUMO

Asporin has been reported as a tumor suppressor in breast cancer, while asporin-activated invasion has been described in gastric cancer. According to our in silico search, high asporin expresion associates with significantly better relapse free survival (RFS) in patients with low-grade tumors but RFS is significantly worse in patients with grade 3 tumors. In line with other studies, we have confirmed asporin expression by RNA scope in situ hybridization in cancer associated fibroblasts. We have also found asporin expression in the Hs578T breast cancer cell line which we confirmed by quantitative RT-PCR and western blotting. From multiple testing, we found that asporin can be downregulated by bone morphogenetic protein 4 while upregulation may be facilited by serum-free cultivation or by three dimensional growth in stiff Alvetex scaffold. Downregulation by shRNA inhibited invasion of Hs578T as well as of CAFs and T47D cells. Invasion of asporin-negative MDA-MB-231 and BT549 breast cancer cells through collagen type I was enhanced by recombinant asporin. Besides other investigations, large scale analysis of aspartic acid repeat polymorphism will be needed for clarification of the asporin dual role in progression of breast cancer.


Assuntos
Neoplasias da Mama/patologia , Proteínas da Matriz Extracelular/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Intervalo Livre de Doença , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Estimativa de Kaplan-Meier , Prognóstico , Microambiente Tumoral/fisiologia
6.
Cell Cycle ; 11(20): 3837-50, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22983061

RESUMO

Impaired DNA damage response pathways may create vulnerabilities of cancer cells that can be exploited therapeutically. One such selective vulnerability is the sensitivity of BRCA1- or BRCA2-defective tumors (hence defective in DNA repair by homologous recombination, HR) to inhibitors of the poly(ADP-ribose) polymerase-1 (PARP-1), an enzyme critical for repair pathways alternative to HR. While promising, treatment with PARP-1 inhibitors (PARP-1i) faces some hurdles, including (1) acquired resistance, (2) search for other sensitizing, non-BRCA1/2 cancer defects and (3) lack of biomarkers to predict response to PARP-1i. Here we addressed these issues using PARP-1i on 20 human cell lines from carcinomas of the breast, prostate, colon, pancreas and ovary. Aberrations of the Mre11-Rad50-Nbs1 (MRN) complex sensitized cancer cells to PARP-1i, while p53 status was less predictive, even in response to PARP-1i combinations with camptothecin or ionizing radiation. Furthermore, monitoring PARsylation and Rad51 foci formation as surrogate markers for PARP activity and HR, respectively, supported their candidacy for biomarkers of PARP-1i responses. As to resistance mechanisms, we confirmed the role of the multidrug resistance efflux transporters and its reversibility. More importantly, we demonstrated that shRNA lentivirus-mediated depletion of 53BP1 in human BRCA1-mutant breast cancer cells increased their resistance to PARP-1i. Given the preferential loss of 53BP1 in BRCA-defective and triple-negative breast carcinomas, our findings warrant assessment of 53BP1 among candidate predictive biomarkers of response to PARPi. Overall, this study helps characterize genetic and functional determinants of cellular responses to PARP-1i and contributes to the search for biomarkers to exploit PARP inhibitors in cancer therapy.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias/tratamento farmacológico , Poli(ADP-Ribose) Polimerases/genética , Hidrolases Anidrido Ácido , Antineoplásicos/farmacologia , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Biomarcadores Tumorais/metabolismo , Camptotecina/farmacologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Dano ao DNA , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Raios gama/uso terapêutico , Genes MDR , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteína Homóloga a MRE11 , Masculino , Neoplasias/genética , Neoplasias/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/metabolismo , Reparo de DNA por Recombinação/efeitos dos fármacos , Reparo de DNA por Recombinação/efeitos da radiação , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
7.
J Nat Prod ; 67(7): 1100-5, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15270560

RESUMO

In this study, the relationships between the chemical structure and cytotoxic activity of betulinic acid (1) derivatives were investigated. Eight lupane derivatives (1-8), one of them new (6), five diosphenols (9-13), four of them new (10-13), two new norderivatives (14 and 15), five seco derivatives (16-20), four of them new (16, 17, 19, and 20), and three new seco-anhydrides (21-23) were synthesized from 1, and their activities were compared with the activities of known compounds. The effects of substitution on the A-ring and esterification of the carboxyl group in position 28 on cytotoxicity were of special interest. Significant cytotoxic activity against the T-lymphoblastic leukemia cell line CEM was found in diosphenols 9 and 13 (TCS(50) 4 and 5 micromol/L) and seco-anhydrides 22 and 23 (TCS(50) 7 and 6 micromol/L). All compounds were also tested on cancer cell lines HT 29, K562, K562 Tax, and PC-3, and these confirmed activity of diosphenols 9, 10, and 11 and anhydride 22. Diosphenols, as the most promising group of derivatives, were further tested on four more lines (A 549, DU 145, MCF 7, SK-Mel2).


Assuntos
Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Técnicas de Química Combinatória , Triterpenos/síntese química , Triterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Triterpenos Pentacíclicos , Relação Estrutura-Atividade , Células Tumorais Cultivadas , Ácido Betulínico
8.
J Med Chem ; 46(25): 5402-15, 2003 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-14640549

RESUMO

Cellular screening of various synthetic triterpenoid compounds formally derived from lupane has identified a number of analogues as potential anticancer drug candidates. Here we describe the synthesis and structure-activity relationships of betulin and betulinic acid derivatives containing an E-ring modified with different oxygen functions. Thus compounds containing the lup-18-en-21-one, lup-18-ene-21,22-dione, 18,19-secolupane, and the highly oxygenated 18,19-secolupane systems, as well as des-E-lupane derivatives, were prepared from the readily available natural pentacyclic triterpene betulin using oxidative procedures. These compounds were named betulinines. We demonstrate that only selected compounds, particularly those containing a lupane E-ring-derived unsaturated ketone or diketone function, possessed in vitro cytotoxic activity against tumor cell lines, suggesting a structure-activity relationship.


Assuntos
Antineoplásicos/síntese química , Apoptose , Triterpenos/síntese química , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos , Estereoisomerismo , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/farmacologia
9.
EMBO J ; 21(17): 4621-31, 2002 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-12198164

RESUMO

The mammalian SIN3 complex consists of histone deacetylases (HDAC1, HDAC2), several known proteins (SAP30, N-CoR) and as yet unidentified proteins. Here we show that the mouse tetradecanoyl phorbol acetate induced sequence 7 (TIS7) protein is a novel transcriptional co-repressor that can associate with the SIN3 complex. We have identified tis7 as a gene that is up-regulated upon loss of polarity in a mouse mammary gland epithelial cell line expressing an estrogen-inducible c-JunER fusion protein. In unpolarized cells, TIS7 protein levels increase and TIS7 translocates into the nucleus. Overexpression of tis7 causes loss of polarity and represses a set of genes, as revealed by cDNA microarray analysis. We have shown that TIS7 protein interacts with several proteins of the SIN3 complex (mSin3B, HDAC1, N-CoR and SAP30) by yeast two-hybrid screening and co-immunoprecipitations. TIS7 co-immunoprecipitated HDAC complex is enzymatically active and represses a GAL4-dependent reporter transcription. The transcriptional repression of endogenous genes by tis7 overexpression is HDAC dependent. Thus, we propose TIS7 as a transcriptional co-repressor affecting the expression of specific genes in a HDAC activity-dependent manner during cell fate decisions, e.g. scattering.


Assuntos
Células Epiteliais/metabolismo , Histona Desacetilases/metabolismo , Proteínas Imediatamente Precoces/metabolismo , Proteínas de Membrana/metabolismo , Complexos Multienzimáticos/metabolismo , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Polaridade Celular , DNA Complementar/genética , Estradiol/farmacologia , Feminino , Perfilação da Expressão Gênica , Células HeLa , Histona Desacetilase 1 , Histona Desacetilase 2 , Humanos , Glândulas Mamárias Animais/citologia , Camundongos , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Correpressor 1 de Receptor Nuclear , Análise de Sequência com Séries de Oligonucleotídeos , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-jun/fisiologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Complexo Correpressor Histona Desacetilase e Sin3 , Transcrição Gênica
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