RESUMO
Cancer cells efficiently transfer exosome contents (essentially mRNAs and microRNAs) to other cell types, modifying immune responses, cell growth, angiogenesis and metastasis. Here we analyzed the exosomes release by breast tumor cells with different capacities of stemness/metastasis based on CXCR4 expression, and evaluated their capacity to generate oncogenic features in recipient cells. Breast cancer cells overexpressing CXCR4 showed an increase in stemness-related markers, and in proliferation, migration and invasion capacities. Furthermore, recipient cells treated with exosomes from CXCR4-cells showed increased in the same abilities. Moreover, inoculation of CXCR4-cell-derived exosomes in immunocompromised mice stimulated primary tumor growth and metastatic potential. Comparison of nucleic acids contained into exosomes isolated from patients revealed a "stemness and metastatic" signature in exosomes of patients with worse prognosis. Finally, our data supported the view that cancer cells with stem-like properties show concomitant metastatic behavior, and their exosomes stimulate tumor progression and metastasis. Exosomes-derived nucleic acids from plasma of breast cancer patients are suitable markers in the prognosis of such patients.
Assuntos
Neoplasias da Mama/patologia , Proliferação de Células , Transformação Celular Neoplásica/patologia , Exossomos/genética , Regulação Neoplásica da Expressão Gênica , Células-Tronco Neoplásicas/patologia , Receptores CXCR4/metabolismo , Animais , Apoptose , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Movimento Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Camundongos , Camundongos Nus , Metástase Neoplásica , Células-Tronco Neoplásicas/metabolismo , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores CXCR4/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
AIM: To examine the endothelium-dependent relaxation of splanchnic arteries during cirrhosis as well as the role of reactive oxygen species in this relaxation using hepatic arteries from cirrhotic patients undergoing liver transplantation and mesenteric arteries from liver donors. METHODS: Arterial segments 3 mm long were mounted in organ baths for isometric tension recording and precontracted with the thromboxane A(2) analog U46619 (10(-7)-10(-6) M). RESULTS: The relaxation to acetylcholine (10(-8)-10(-4) M), but not to sodium nitroprusside (10(-8)-10(-4) M) was lower in hepatic arteries. The inhibitor of nitric oxide synthesis, N(omega)-nitro-l-arginine methyl ester (l-NAME, 10(-4) M), the inhibitor of cyclooxygenase, meclofenamate (10(-5) M), or l-NAME (10(-4) M) + meclofenamate (10(-5) M) diminished the relaxation to acetylcholine only in mesenteric arteries. l-NAME (10(-4) M) + meclofenamate (10(-5) M) combined with charybdotoxin (10(-7) M) + apamine (10(-6) M) inhibited the relaxation toacetylcholine in both types of arteries, and this inhibition was greater than with l-NAME + meclofenamate. The scavenger of hydrogen peroxide, catalase (1000 U/mL), the superoxide dismutase mimetic, tiron (10(-2) M) or the inhibitor of NAD(P)H oxidase, diphenyleneiodonium (5 x 10(-6) M), but not the inhibitor of superoxide dismutase, diethyldithiocarbamate (10(-3) M) potentiated the acetylcholine-induced relaxation only in hepatic arteries. l-NAME did inhibit the relaxation to acetylcholine in hepatic arteries pretreated with catalase or tiron. CONCLUSIONS: Cirrhosis may decrease endothelial release and/or bioavailability of nitric oxide and prostacyclin in splanchnic arteries, which might be caused partly by increased production of reactive oxygen species.
RESUMO
OBJECTIVE: To assess the real utility of orthotopic liver transplantation (OLT) in patients with cholangiocarcinoma, we need series with large numbers of cases and long follow-ups. The aim of this paper is to review the Spanish experience in OLT for hilar and peripheral cholangiocarcinoma and to try to identify the prognostic factors that could influence survival. SUMMARY BACKGROUND DATA: Palliative treatment of nondisseminated irresectable cholangiocarcinoma carries a zero 5-year survival rate. The role of OLT in these patients is controversial, due to the fact that the survival rate is lower than with other indications for transplantation and due to the lack of organs. METHODS: We retrospectively reviewed 59 patients undergoing OLT in Spain for cholangiocarcinoma (36 hilar and 23 peripheral) over a period of 13 years. We present the results and prognostic factors that influence survival. RESULTS: The actuarial survival rate for hilar cholangiocarcinoma at 1, 3, and 5 years was 82%, 53%, and 30%, and for peripheral cholangiocarcinoma 77%, 65%, and 42%. The main cause of death, with both types of cholangiocarcinoma, was tumor recurrence (present in 53% and 35% of patients, respectively). Poor prognosis factors were vascular invasion (P < 0.01) and IUAC classification stages III-IVA (P < 0.01) for hilar cholangiocarcinoma and perineural invasion (P < 0.05) and stages III-IVA (P < 0.05) for peripheral cholangiocarcinoma. CONCLUSIONS: OLT for nondisseminated irresectable cholangiocarcinoma has higher survival rates at 3 and 5 years than palliative treatments, especially with tumors in their initial stages, which means that more information is needed to help better select cholangiocarcinoma patients for transplantation.
