RESUMEN
Hearing loss is a major health concern affecting millions of people worldwide with currently limited treatment options. In clarin-2-deficient Clrn2-/- mice, used here as a model of progressive hearing loss, we report synaptic auditory abnormalities in addition to the previously demonstrated defects of hair bundle structure and mechanoelectrical transduction. We sought an in-depth evaluation of viral-mediated gene delivery as a therapy for these hearing-impaired mice. Supplementation with either the murine Clrn2 or human CLRN2 genes preserved normal hearing in treated Clrn2-/- mice. Conversely, mutated forms of CLRN2, identified in patients with post-lingual moderate to severe hearing loss, failed to prevent hearing loss. The ectopic expression of clarin-2 successfully prevented the loss of stereocilia, maintained normal mechanoelectrical transduction, preserved inner hair cell synaptic function, and ensured near-normal hearing thresholds over time. Maximal hearing preservation was observed when Clrn2 was delivered prior to the loss of transducing stereocilia. Our findings demonstrate that gene therapy is effective for the treatment of post-lingual hearing impairment and age-related deafness associated with CLRN2 patient mutations.
Asunto(s)
Células Ciliadas Auditivas , Pérdida Auditiva , Humanos , Animales , Ratones , Células Ciliadas Auditivas/metabolismo , Audición , Pérdida Auditiva/genética , Pérdida Auditiva/terapia , Estereocilios/metabolismo , Suplementos DietéticosRESUMEN
BACKGROUND: Hepatocellular carcinoma is the fifth most common cancer worldwide, with poor prognosis and resistance to chemotherapy. This gives novel cancer treatment methods an overwhelming significance. Epigenetic therapy of cancer is useful in reversing some of the cancer defects because of reversibility of the epigenetic alterations. Non-protein coding transcripts are the major part of our transcriptome. MEG3 is a tumor suppressor long non-coding RNA being expressed in many normal tissues. Methylation of MEG3 promoter region elicits the decrease in its expression in hepatocellular cancer cells. Bioactive nutrients including curcumin offer great potential in altering DNA methylation status which is catalyzed via DNMT1, DNMT3A and 3B. PURPOSE: Herein, we aimed to study RNA-based epigenetic effects of dendrosomal curcumin (DNC) on hepatocellular cancer (HCC). STUDY DESIGN: To this end miRNA-dependent regulation of MEG3 expression under treatment with DNC was studied by evaluating the modulatory involvement of miR-29a for DNMT3A and 3B and miR-185 for DNMT1. METHODS: We evaluated DNC entrance to HCC cells with the use of fluorescent characteristics of curcumin. Next we performed the MTT assay to evaluate DNC and dendrosome effects on HCC cell viability. The coding and non-coding genes expression analyses were done using quantitative-PCR. RESULTS: In result we found that the DNC dependent overexpression of miR-29a and miR-185 (P < 0.01) can down-regulate the expression of DNMT1, 3A and 3B (P < 0.05) and subsequently overexpresses MEG3 (P < 0.05). CONCLUSION: DNC potentially can induce DNA hypomethylation and reexpression of silenced tumor suppressor genes in HCC. These data suggest that DNC could be an effective choice for epigenetic therapy of HCC.
Asunto(s)
Curcumina/química , Metilación de ADN , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral/efectos de los fármacos , ADN (Citosina-5-)-Metiltransferasa 1 , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , ADN Metiltransferasa 3A , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Células Hep G2/efectos de los fármacos , Humanos , Neoplasias Hepáticas/patología , MicroARNs/genética , Regiones Promotoras Genéticas , ARN Largo no Codificante/genética , Regulación hacia Arriba , ADN Metiltransferasa 3BRESUMEN
Application of nanoparticles has recently promising results for water insoluble agents like curcumin. In this study, we synthesized polymeric nanoparticle-curcumin (PNPC) and then showed its efficiency, drug loading, stability, and safety. Therapeutic effects of PNPC were also assessed on two cell lines and in an animal model of breast cancer. PNPC remarkably suppressed mammary and hepatocellular carcinoma cells proliferation (P < 0.05). Under the dosing procedure, PNPC was safe at 31.25 mg/kg and lower doses. Higher doses demonstrated minimal hepatocellular and renal toxicity in paraclinical and histopathological examinations. Tumor take rate in PNPC-treated group was 37.5% compared with 87.5% in control (P < 0.05). Average tumor size and weight were significantly lower in PNPC group than control (P < 0.05). PNPC increased proapoptotic Bax protein expression (P < 0.05). Antiapoptotic Bcl-2 protein expression, however, was lower in PNPC-treated animals than the control ones (P < 0.05). In addition, proliferative and angiogenic parameters were statistically decreased in PNPC-treated animals (P < 0.05). These results highlight the suppressing role for PNPC in in vitro and in vivo tumor growth models. Our findings provide credible evidence for superior biocompatibility of the polymeric nanocarrier in pharmacological arena together with an excellent tumor-suppressing response.