RESUMEN
MALDI-TOF MS was used to recognise serum peptidome profiles predictive of mortality in women affected by early BCa. Mortality was analysed based on signal profiling, and appropriate statistics were used. The results indicate that four signals were increased in deceased patients compared with living patients. Three of the four signals were individually associated with all-cause mortality, but only one having mass/charge ratio (m/z) 1,046.49 was associated with BCa-specific mortality and was the only peak to maintain an independent prognostic role after multivariate analysis. Two groups exhibiting different mortality probabilities were identified after clustering patients based on the expression of the four peptides, but m/z 1,046.49 was exclusively expressed in the cluster exhibiting the worst mortality outcome, thus confirming the crucial value of this peptide. The specific role of this peak was confirmed by competing risk analysis. MS findings were validated by ELISA analysis after demonstrating that m/z 1,046.49 structurally corresponded to Angiotensin II (ATII). In fact, mortality results obtained after arbitrarily dividing patients according to an ATII serum value of 255 pg/ml (which corresponds to the 66(th) percentile value) were approximately comparable to those previously demonstrated when the same patients were analysed according to the expression of signal m/z 1,046.49. Similarly, ATII levels were specifically correlated with BCa-related deaths after competing risk analysis. In conclusion, ATII levels were increased in women who exhibited worse mortality outcomes, reinforcing the evidence that this peptide potentially significantly affects the natural history of early BCa. Our findings also confirm that MALDI-TOF MS is an efficient screening tool to identify novel tumour markers and that MS findings can be rapidly validated through less complex techniques, such as ELISA.
Asunto(s)
Angiotensina II/sangre , Biomarcadores de Tumor/sangre , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Proteómica/métodos , Factores de RiesgoRESUMEN
INTRODUCTION: Non-small cell lung cancer (NSCLC) is a major cause of cancer-related death worldwide. Although advanced NSCLC is still incurable, various anti-neoplastic agents have become available for the treatment of this disease. Pemetrexed , a multi-target folate antagonist, has improved the survival of non-squamous NSCLC patients. Currently, pemetrexed is approved for first-line treatment in combination with a platinum derivate, for second-line treatment as a single agent and, more recently, as maintenance treatment after first-line chemotherapy. AREAS COVERED: The authors analyzed the state of the art of pemetrexed through a review of the literature. Clinical trials and meta-analyses involving pemetrexed in NSCLC were evaluated. Pemetrexed improved survival of non-squamous NSCLC in first-line, maintenance, and second-line treatments; this benefit is limited to non-squamous histology. Because pemetrexed has become part of the standard of care, current clinical trials are designed to compare it to other investigational combinations. Limited data on resectable disease are available, and additional clinical trials are being conducted. EXPERT OPINION: Pemetrexed has shown effectiveness and a favorable toxicity profile. Histology-driven indications and the relationship of pemetrexed with thymidylate synthase expression suggest that a more precise definition of predictive biomarkers could be further investigated.
Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Glutamatos/uso terapéutico , Guanina/análogos & derivados , Neoplasias Pulmonares/tratamiento farmacológico , Antineoplásicos/economía , Antineoplásicos/farmacología , Análisis Costo-Beneficio , Glutamatos/economía , Glutamatos/farmacología , Guanina/economía , Guanina/farmacología , Guanina/uso terapéutico , Humanos , PemetrexedRESUMEN
Gemcitabine is an inhibitor of ribonucleotide reductase (RR) and DNA polymerization with promising activity in hematologic malignancies. Gemcitabine enters the cell mostly via the human equilibrative nucleoside transporter-1 (hENT1), while drug metabolism occurs by phosphorylation by deoxycytidine kinase (dCK), 5'-nucleotidase (cN-II) and cytidine deaminase (CDA) are the main inactivating enzymes. The aim of this study was to investigate the role of these determinants in gemcitabine cytotoxicity and analyze their expression in lymphoid cells. Cytotoxicity was assessed by MTT, and modulated by simultaneous addition of 2'-deoxycytidine (dCK natural substrate), tetrahydrouridine (CDA competitive inhibitor) and diethylpyrocarbonate (cN-II non-competitive inhibitor), while the expression of hENT1, dCK, cN-II, CDA and RR in WIL2-S, Jurkat and CCRF-CEM cells as well as in lymphoid cells from 25 chronic lymphocytic B-leukemia (B-CLL) patients was studied with quantitative-PCR. Cell cycle modulation and induction of apoptosis were analyzed by cytofluorimetry and bisbenzimide staining. Gemcitabine was highly cytotoxic, increased the cells in S-phase and significantly enhanced apoptosis. The crucial role of metabolism in gemcitabine activity was confirmed by the significant modulation of cytotoxicity by inhibitors of dCK, CDA and cN-II. Furthermore, PCR demonstrated a correlation between gemcitabine sensitivity and expression of its determinants, and that their values were within those observed in patients. These data indicate that gemcitabine is cytotoxic against lymphoid cells, affecting cell cycle and apoptosis. Furthermore, chemosensitivity may be predicted on the basis of gene expression profile of critical determinants involved in gemcitabine mechanism of action, suggesting the use of pharmacogenetic profiling for treatment optimization.