Benefiting from the synergy of the enhancement of photonic crystals and enzymatic cycle amplification, we realize high sensitivity detection of miRNA-21 with a detection range of 1 pM-10 nM and a detection limit of about four orders of magnitudes lower than the method employs no amplification, showing an expectable prospect in the early diagnosis of cancer.
Emerging evidence has shown that macrophages could play an essential role in mediating the chemoresistance of cancer cells. miR-21 has been reported to be an oncogene, which promotes chemoresistance in cancer.
Taking advantage of the nonfouling property of PEG hydrogel, direct quantification of miRNA-21 was achieved from crude cancer cell lysates with a detection limit down to 10 equivalent cells.
Previous reports showed an over-expression of miRNA-21 (miR-21) in various cancer cells, and its up-regulation is closely related to cancer initiation, proliferation and metastasis.
Together, the findings demonstrated miR‑21 inhibitor facilitated the anti‑cancer activity of DLN in melanoma, and the mechanisms involved Bcl‑2, Bax and P53 expression.
MicroRNA (miRNA) are small, non-coding RNA involved in post-transcriptional regulation of gene expression. miR-21 is an oncomiR that is dysregulated in a significant fraction of human malignancies, and its overexpression is linked to poor overall survival, chemoresistance, and radioresistance in several human cancers.
Survival analysis showed that the survival time of patients with high expression of miR-21 was significantly shorter than that of patients with low expression of miR-21, while survival time of patients with high expression of miR-138 was significantly longer than that of patients with low expression of miR-138 (log-rank, P<0.05). miR-21 is highly expressed in colon cancer tissues and is positively associated with the degree of malignancy of patients but negatively associated with survival. miR-138 expression is low in colon cancer tissues and is negatively associated with the degree of malignancy of patients but positively associated with survival. miR-21 and miR-138 may be involved in the regulation of colon cancer cell proliferation.
Plasma levels of lncRNA HAND2-AS1 were lower in ESCC patients than in healthy controls, and downregulation of plasma lncRNA HAND2-AS1 distinguished early stage ESCC patients from healthy controls. lncRNA HAND2-AS1 overexpression resulted in downregulation of miRNA-21 in cells of ESCC cell lines and inhibited cell proliferation, migration, and invasion. miRNA-21 overexpression failed to affect lncRNA HAND2-AS1 expression but significantly attenuated the inhibitory effect of lncRNA HAND2-AS1 overexpression on cancer cell proliferation, migration, and invasion.
microRNA-21 was up-regulated in HER2 positive and Basal-like breast cancer types, while microRNA-206 was up-regulated in Luminal A and B types of breast cancer. microRNA-21 expression negatively correlated with the level of ER and PR but positively correlated with HER2 expression and tumor malignancy, while microRNA-206 showed the opposite trend.
<b>Conclusion:</b> Our findings suggested that the exosomal miR-21 and miR-10b induced by acidic microenvironment in HCC promote cancer cell proliferation and metastasis and may serve as prognostic molecular markers and therapeutic targets for HCC.
However, sensitive and accurate detection of miR-21 is very challenging in that up-regulation of miR-21 is highly associated with several types of malignant tumors.
Previous studies have reported that microRNAs regulate gene expression and transcription. miR-21 have been identified to play a role in many types of cancer.
To display the application of this novel terminal protection, a multifunctional DNA is designed to quantify the model circulating microRNA (hsa-miR-21-5p) in serums from different cancer patients.