There is increasing evidence that some microRNAs change their levels in reaction to xenobiotic challenge. The aim of this study was to test the possible involvement of micro-RNAs in response to standard anticancer treatment. Tumor biopsies from 35 patients with rectal cancer before therapy and parallel tumor biopsies from 31 patients two weeks after starting preoperative capecitabine chemoradiotherapy were taken. The expression levels of single miRNA species were measured using TaqMan Micro-RNA assays after reverse transcription from isolated total RNAs. Many micro-RNAs (miR10a, miR21, miR145, miR212, miR339, miR361) responded to chemoradiotherapy in individual tumor samples, but there was profound intertumoral variability. However, other two micro-RNAs miR125b, miR137 showed a significant increase in median expression levels after starting therapy in most samples. Moreover, our results for the first time show that higher induced levels of miR125b and miR137 are associated with worse response to the therapy.
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Bull Exp Biol Med
June 2023
N. N. Blokhin National Medical Research Center of Oncology, Ministry of Health of the Russian Federation, Moscow, Russia.
The role of methylation of 9 miRNA genes in the pathogenesis of metastatic clear cell renal cell carcinoma was determined by quantitative methylation-specific PCR (MS-PCR). For 5 genes (MIR125B-1, MIR137, MIR193A, MIR34B/C, and MIR375), a significant correlation of high methylation level with late (III-IV) stages, large size (T3+T4) of the tumor, and metastasis to lymph nodes and/or distant organs was revealed. For another group of genes (MIR125B-1, MIR1258, MIR193A, MIR34B/C, and MIR375), a statistically significant correlation of high methylation level with loss of differentiation in the tumor (G3-G4) was found, and the opposite pattern was found for MIR203A.
View Article and Find Full Text PDFDiagnostics (Basel)
July 2023
Research Centre for Medical Genetics, 1 Moskvorechye St., Moscow 115522, Russia.
Clear cell renal cell carcinoma (ccRCC) is the most common and aggressive histological type of cancer in this location. Distant metastases are present in approximately 30% of patients at the time of first examination. Therefore, the ability to predict the occurrence of metastases in patients at early stages of the disease is an urgent task aimed at personalized treatment.
View Article and Find Full Text PDFBull Exp Biol Med
December 2022
P. K. Anokhin Research Institute of Normal Physiology, Moscow, Russia.
We studied changes in the level of methylation of a number of microRNA genes hypermethylated in non-small cell lung cancer and its histological subtypes as well as the relationship of methylation of a group of microRNA genes with clinical and morphological features of the tumor with smoking status. A significantly high level of methylation of 7 genes (MIR124-1/3, MIR125B-1, MIR129-2, MIR137, MIR1258, and MIR339) was revealed in adenocarcinoma and squamous cell lung cancer in comparison with samples of adjacent histologically unchanged lung tissue. In squamous cell lung cancer, a significantly high level of methylation of the MIR124-2 gene in the tumor was also shown.
View Article and Find Full Text PDFDiscov Oncol
September 2021
Clinical Laboratory, The Second Hospital of Jilin University, Changchun, 130000, China.
Sphingosine-1-phosphate (S1P), a pleiotropic lipid mediator, participates in various cellular processes during tumorigenesis, including cell proliferation, survival, drug resistance, metastasis, and angiogenesis. S1P is formed by two sphingosine kinases (SphKs), SphK1 and SphK2. The intracellularly produced S1P is delivered to the extracellular space by ATP-binding cassette (ABC) transporters and spinster homolog 2 (SPNS2), where it binds to five transmembrane G protein-coupled receptors to mediate its oncogenic functions (S1PR1-S1PR5).
View Article and Find Full Text PDFOur work aimed to differentiate 20 aberrantly methylated miRNA genes that participate at different stages of development and metastasis of ovarian carcinoma (OvCa) using methylation-specific qPCR in a representative set of clinical samples: 102 primary tumors without and with metastases (to lymph nodes, peritoneum, or distant organs) and 30 peritoneal macroscopic metastases (PMM). Thirteen miRNA genes (, , , , , , , , , , , , and ) were hypermethylated already at the early stages of OvCa, while hypermethylation of , , , and was pronounced in metastatic tumors, and showed high methylation levels specifically in PMM. We confirmed the significant relationship between methylation and expression levels for 11 out of 12 miRNAs analyzed by qRT-PCR.
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