As an illustration, colorimetric responses were obtained for lung cancer associated miRNA sequence (mir21) in human plasma, with a detection limit of 10 nM, illustrating the feasibility of proposed methodology for clinical applications without involving sophisticated instrumentation.
Lung cancer is the most common solid tumor and the leading cause of cancer-related mortality worldwide. miR-21 is one of the most commonly observed aberrant miRNAs in human cancers.
Herein, we develop an isothermal miRNA detection platform based on the highly efficient, multiple primer-mediated rolling circle amplification method coupled with a graphene oxide-based fluorescence (MPRCA-GO) assay, using lung cancer-associated miRNAs (miR-21 and miR-210) and a reference miRNA (miR-16) as model targets.
This background is then illuminated from a clinical perspective on microRNA-21 and microRNA-34 as general examples for the complex microRNA biology in lung cancer and its diagnostic value.
By monitoring the SERS signal quenching of the MBs in the presence of target miRNA biomarkers, three lung cancer related-miRNAs (miRNA-21, miRNA-486, and miRNA-375) in buffer and human serum were simultaneously assayed using the SERS sensor array, and the limits of detection of the three miRNAs in human serum are 393 aM, 176 aM, and 144 aM, respectively.
In the first experiment, three miRNAs, proposed in the literature as lung cancer biomarkers (miR-21, miR-126 and let-7a), were analyzed in a set of 15 human serum samples.
We utilize transgenic mice with loss-of-function and gain-of-function miR-21 alleles combined with a model of NSCLC to determine the role of miR-21 in lung cancer.
In conclusion, this study demonstrated that miR-21 silencing reversed lung cancer cell MDR by modulation of MDR-related gene expression and inhibition of the AKT signaling pathway, suggesting that miR-21 may be a potential therapeutic candidate in patients with MDR lung cancer.
Systemic delivery of LNA-anti-miR-21 in combination with cisplatin in vivo completely suppressed the development of lung tumors in a mouse model of lung cancer.
In summary, our results suggest that miR-21, miR-205, miR-30d, and miR-24 may serve as potential novel non-invasive biomarkers for diagnosis of lung cancer.
As a proof of concept, the proposed methodology is validated using two biomarkers; lung cancer associated microRNA (mir21) and hepatitis B virus DNA (HBV-DNA).
In addition, 4 microRNAs were investigated (miRNA 21, miRNA 155, miRNA 200c, and miRNA 34a) because their relation to lung cancer has been documented recently.
In summary, our data demonstrate that growth conditions especially expected in more malignant tumors result in microRNA-21 upregulation explaining the observed increase in higher staged lung cancer tissue, but not in lung cancer-derived cells.
Increased miR-21-5p delivery by MSC-EV after hypoxia pre-challenge can promote lung cancer development by reducing apoptosis and promoting macrophage M2 polarization.
The present study aimed to investigate the association between miR‑21 expression, cell viability and apoptosis in a lung cancer cell line, and to elucidate the potential mechanisms. miR‑21 or small interfering RNA against miR‑21 were transfected into A549 non‑small cell lung cancer cells.
The aim of this study was to evaluate for the first time in lung cancer the use of liquid-based cytology both for EGFR and KRAS mutational testing and for the expression trend of some miRNAs involved in lung cancer pathogenesis: miR-21, miR-155, miR-7, and let7a.