RESUMO
The most common endocrine malignancy is thyroid cancer, and researchers have made a great deal of progress in deciphering its molecular mechanisms in the recent years. Many of molecular changes observed in thyroid cancer can be used as biomarkers for diagnosis, prognosis, and therapeutic targets for treatment. MicroRNAs (miRNAs) are important parts in biological and metabolic pathways such as regulation of developmental stages, signal transduction, cell maintenance, and differentiation. Therefore, their dysregulation can expose individuals to malignancies. It has been proved that miRNA expression is dysregulated in different types of tumors, like thyroid cancers, and can be the cause of tumor initiation and progression. In this paper, we have reviewed the available data on miRNA dysregulation in different thyroid tumors including papillary, follicular, anaplastic, and medullary thyroid carcinomas aiming to introduce the last updates in miRNAs-thyroid cancer relation.
Assuntos
MicroRNAs/genética , MicroRNAs/uso terapêutico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/terapia , Regulação Neoplásica da Expressão Gênica , Humanos , PrognósticoRESUMO
Breast cancer is a heterogeneous disease, and among all types, triple-negative breast cancer (TNBC) is characterised by high risk of recurrence. The discovery of microRNAs (miRNA) has opened the door for targeted therapy of TNBC. miR-340 down-regulation and sub-G1-accumulated cells in flowcytometry were observed in metastatic TNBC cells (data in publication), leading us to investigate the potential tumour suppressive role of this miRNA on cell-cycle-related genes. A lentiviral vector containing miR-340 was applied to over-express miR-340 in TNBC cell line, MDA-MB-231. Then, the expression of some cell-cycle-regulating genes including cyclin A2 (cyclin A2), Cyclin-dependent kinases 2 (CDK2), cyclin-dependent kinase inhibitors (P16, P18 and P27), Retinoblastoma (RB) and transcription factors (SMAD 4, SOX2 and SOX17) was investigated using quantitative RT-PCR. The results showed a decline in the expression of SOX2, P16 and P27 after miR-340 over-expression, whereas we observed an increase in the expression of cyclin A2, CDK2, SOX17, P18, SMAD 4 and RB. The over-expression of tumour suppressor genes such as RB and SOX17 and down-regulation of an oncogene such as SOX2 were in accordance to the inhibitory role of miR-340 that causes blockage of breast cancer metastasis which should be further investigated.
Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias de Mama Triplo Negativas/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Ciclina A2/genética , Quinase 2 Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p18/genética , Inibidor de Quinase Dependente de Ciclina p27/genética , Vetores Genéticos , Humanos , Lentivirus , Metástase Neoplásica , Proteína do Retinoblastoma/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXF/genética , Proteína Smad4/genética , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
BACKGROUND AND OBJECTIVES: Developed in 1991, nucleic acid sequence-based amplification (NASBA) has been introduced as a rapid molecular diagnostic technique, where it has been shown to give quicker results than PCR, and it can also be more sensitive. This paper describes the development of a molecular beacon-based multiplex NASBA assay for simultaneous detection of HIV-1 and HCV in plasma samples. MATERIALS AND METHODS: A well-conserved region in the HIV-1 pol gene and 5'-NCR of HCV genome were used for primers and molecular beacon design. The performance features of HCV/HIV-1 multiplex NASBA assay including analytical sensitivity and specificity, clinical sensitivity and clinical specificity were evaluated. RESULTS: The analysis of scalar concentrations of the samples indicated that the limit of quantification of the assay was <1000 copies/ml for HIV-1 and <500 copies/ml for HCV with 95% confidence interval. Multiplex NASBA assay showed a 98% sensitivity and 100% specificity. The analytical specificity study with BLAST software demonstrated that the primers do not attach to any other sequences except for that of HIV-1 or HCV. The primers and molecular beacon probes detected all HCV genotypes and all major variants of HIV-1. CONCLUSION: This method may represent a relatively inexpensive isothermal method for detection of HIV-1/HCV co-infection in monitoring of patients.
RESUMO
BACKGROUND AND OBJECTIVES: HIV-1 and HCV infections are life threatening problems in patients who receive blood products. Serological methods have proven useful in detecting these infections, but there are setbacks that make it challenging to detect these infectious agents. By the advent of Nucleic Acid Testing (NAT) methods, especially in multiplex format, more precise detection is possible. MATERIALS AND METHODS: We have developed a multiplex RT-PCR assay for simultaneous detection of HIV-1 and HCV. Primers were designed for highly conserved region of genome of each virus. Using these primers and standard plasmids, we determined the limit of detection, clinical and analytical specificity and sensitivity of the assay. Monoplex and multiplex RT-PCR were performed. RESULTS: Analytical sensitivity was considered to be 100 and 200 copies/ml for HIV-1 and HCV, respectively. High concentration of one virus had no significant effect on the detection of the other one with low concentration. By analysis of 40 samples, clinical sensitivity of the assay was determined to be 97.5%. Using different viral and human genome samples, the specificity of the assay was evaluated to be 100%. CONCLUSIONS: The aim of this study was to develop a reliable, rapid and cost effective method to detect HIV-1 and HCV simultaneously. Results showed that this simple and rapid method is perfectly capable of detecting two viruses in clinical samples.
