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1.
EJHaem ; 5(3): 535-540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895084

RESUMO

This study reports the development activities for the Treatment Preference Myelodysplasia Questionnaires (TPMQ) for clinicians (mTPMQ), carers (cTPMQ), and patients (pTPMQ). These tools are intended to evaluate treatment preferences for patients with myelodysplastic syndromes (MDS). This was a non-interventional, cross-sectional qualitative interview study consisting of interviews with clinicians, patients, and those caring for patients with MDS. All participants were located in Australia and data were collected from qualitative mixed-method interviews composed of concept elicitation and cognitive debriefing related to initial drafts of the questionnaires. Fifteen individuals participated in interviews (five from each group). Based on the concept elicitation portion of interviews, concepts of importance were classified and reasons for treatment preference were documented. From cognitive debriefing, the questionnaires were generally deemed to be clear and easy to understand. Participant input from both concept elicitation and cognitive debriefing portions was used to revise initial drafts of the questionnaires. The mTPMQ, cTPMQ, and pTPMQ were developed with direct input from clinicians, patients, and caregivers to assess the key concepts of interest related to the preference for the treatment of MDS and are ready to be used and evaluated further in clinical trials.

2.
EJHaem ; 5(3): 527-534, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895081

RESUMO

Hypomethylating agents are the most widely used upfront therapy for patients with myelodysplastic syndrome (MDS) who are not suitable for hematopoietic stem cell transplantation. In Australia, azacitidine was, until recently, the only approved and subsidized treatment for patients with intermediate-2 and high-risk MDS, chronic myelomonocytic leukemia, and low blast acute myeloid leukemia. We analyzed prescription data to evaluate the real-world persistence and overall survival (OS) of patients prescribed azacitidine for the first time in Australia. A retrospective cohort analysis of patients who had been prescribed Pharmaceutical Benefits Scheme (PBS)-listed azacitidine for the first time, between January 2016 and April 2021, was conducted using the PBS 10% dataset. Treatment persistence and OS were estimated using Kaplan-Meier methods. The impact of the number of treatment cycles and treatment adherence on OS was also estimated. There were 351 patients in the PBS 10% dataset who initiated treatment with azacitidine. The average age (standard deviation [SD]) at azacitidine initiation was 71.9 (11.1) years and the average number (SD) of azacitidine prescriptions was 5.6 (0.2). The median persistence on azacitidine was 15.6 months, and the OS was 13.4 months. The median OS for patients who had six or more cycles of azacitidine treatment was greater compared to patients who had five or less cycles of treatment. The data from this real-world study illustrate the unmet medical needs of patients with MDS treated with azacitidine in Australia. The majority of patients are not treated with the optimal number of cycles of azacitidine, which is negatively correlated with patient outcomes.

3.
Cancer ; 103(12): 2558-65, 2005 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15887222

RESUMO

BACKGROUND: Early detection of hepatocellular carcinoma (HCC), one of the most common and deadly tumors worldwide, still is difficult due to the lack of adequate biomarkers that show high sensitivity and specificity. The authors recently demonstrated that squamous cell carcinoma antigen (SCCA) variants were overexpressed remarkably in all surgically resected HCCs. METHODS: For the current study, the authors assessed the presence of SCCA, as a free form and complexed with immunoglobulins, in serum from patients with HCC, cirrhosis, and chronic hepatitis and from healthy control participants and compared SCCA measurement with the measurement of alpha-fetoprotein (AFP) levels. RESULTS: Circulating immune complexes (ICs) composed by SCCA and immunoglobulin M (IgM) IC (SCCA-IgM IC) were undetectable (< 120 arbitrary units [AU]/mL) in serum from a healthy control population (0 of 73 controls); however, 35 of 50 patients with HCC (70%) were reactive for SCCA-IgM IC independent of etiology (mean +/- standard deviation [SD], 2568.5 +/- 6797.3 AU/mL). No correlation was found with AFP levels, which were elevated significantly in only 21 of 50 patients with HCC (42%). By using an AFP cut-off value of 20 ng/mL, 96% of patients with HCC were positive for at least 1 marker. Among cirrhotic patients, the presence of circulating SCCA-IgM IC was displayed in 13 of 50 patients (26%), but at lower levels compared with the patients who had HCC (mean +/- SD, 147.5 +/- 348.3 AU/mL; P < 0.01; Student t test), whereas 9 of 50 patients with chronic hepatitis (18%) were reactive (mean +/- SD, 39.5 +/- 89.7 AU/mL). No significant presence of free SCCA, free anti-SCCA variants IgG or IgM, or SCCA-IgG IC was found. CONCLUSIONS: The study results indicated that SCCA-IgM ICs represent novel serologic biomarkers, which, alone or in combination with AFP, can increase the sensitivity for diagnosing HCC significantly.


Assuntos
Antígenos de Neoplasias/sangue , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/diagnóstico , Imunoglobulina M/sangue , Serpinas/sangue , Adulto , Idoso , Antígenos de Neoplasias/química , Biomarcadores Tumorais/química , Carcinoma Hepatocelular/química , Feminino , Regulação Neoplásica da Expressão Gênica , Hepatite Crônica/sangue , Hepatite Crônica/diagnóstico , Humanos , Imunoglobulina M/química , Fígado/metabolismo , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/química , Neoplasias Hepáticas/diagnóstico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Serpinas/química , alfa-Fetoproteínas/metabolismo
4.
Eur J Biochem ; 270(9): 1980-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12709057

RESUMO

The dimeric structure of seminal ribonuclease (BS-RNase) is maintained by noncovalent interactions and by two intersubunit disulfide bridges. Another unusual feature of this enzyme is its antitumour action, consisting in a cytotoxic activity selective for malignant cells. This cytotoxic action is exerted when the protein reaches the cytosol of the affected cells, where it degrades ribosomal RNA, thus blocking protein synthesis and leading cells to death. The current model proposed for the mechanism of antitumour action of BS-RNase is based on the ability of the protein to resist the neutralizing action of the cytosolic RNase inhibitor, a resistance due to the dimeric structure of the enzyme. Monomeric RNases, and monomeric derivatives of BS-RNase, are strongly bound by the inhibitor and inactive as antitumor agents. Here we report on monomeric derivatives of BS-RNase that, although strongly inhibited by the cytosolic RNase inhibitor, are cytotoxic towards malignant cells. These monomers are produced by reductive cleavage of the intersubunit disulfides of the native, dimeric protein followed by linking the exposed sulfhydryls to small thiols through formation of mixed disulfides. We found that sulfhydryls from cell monolayers and cell membranes can attack these mixed disulfides in the monomeric derivatives, and reconstitute, through sulfhydryl-disulfide interchange reactions, the native dimeric protein, which is internalized as such, and displays its antitumour action.


Assuntos
Antineoplásicos , Sobrevivência Celular , Dissulfetos/química , Endorribonucleases/química , Endorribonucleases/metabolismo , Células 3T3 , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Bovinos , Linhagem Celular Transformada , Membrana Celular/química , Membrana Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dimerização , Ensaios de Seleção de Medicamentos Antitumorais , Endorribonucleases/farmacologia , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Fibroblastos , Iodoacetamida/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Subunidades Proteicas/farmacologia , Glândulas Seminais/enzimologia
5.
Biochem J ; 362(Pt 3): 553-60, 2002 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11879181

RESUMO

Bovine seminal RNase (BS-RNase) is a dimeric RNase selectively cytotoxic for malignant cells. No information is available on its pathway from the extracellular matrix through the cytosol, where it degrades rRNA. An investigation of this pathway is reported here, carried out by immunofluorescence studies, by assessing the effects on BS-RNase cytotoxicity of drugs that affect specific intracellular compartments and by assaying the behaviour of a protein variant, BS-RNase-KDEL (BS-RNase in which a Lys-Asp-Glu-Leu peptide segment is inserted at the C-terminal ends of the subunit chains), endowed with a consensus sequence that directs proteins to the endoplasmic reticulum. BS-RNase was found to bind both normal and malignant cells and to be internalized by both cell types in endosome vesicles. Non-cytotoxic RNases, such as RNase A and a monomeric derivative of BS-RNase, did not bind to the cell surface and were not internalized. However, an engineered, dimeric and cytotoxic variant of RNase A bound effectively and permeated cells. The results of immunofluorescence studies, the effects of nigericin, monensin and brefeldin A on the cytotoxic action of seminal RNase, and the behaviour of the BS-RNase-KDEL variant, led to the conclusion that the pathway of BS-RNase in malignant cells from the extracellular matrix to the cytosol has two essential intracellular stations: endosomes and the trans-Golgi network. In normal cells, however, the protein does not progress from the endosomal compartment to the Golgi complex.


Assuntos
Endorribonucleases/metabolismo , Células 3T3 , Animais , Bovinos , Linhagem Celular Transformada , Elementos de DNA Transponíveis , Endossomos/enzimologia , Fibroblastos/enzimologia , Variação Genética , Neoplasias dos Genitais Masculinos/enzimologia , Masculino , Camundongos , Proteínas de Neoplasias/metabolismo , Oligopeptídeos/química , Sinais Direcionadores de Proteínas , Subunidades Proteicas , Transporte Proteico , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Sêmen/enzimologia , Rede trans-Golgi/enzimologia
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