microrna-based-liquid-biopsy-experience-plasma-mirna-signature

MicroRNA Based Liquid Biopsy: The Experience of the Plasma miRNA Signature Classifier (MSC) for Lung Cancer Screening

The development of a minimally invasive test, such as liquid biopsy, for early lung cancer detection in its preclinical phase is crucial to improve the ...

Fondazione IRCCS Istituto Nazionale dei Tumori

Research efforts for the management of cancer, in particular for lung cancer, are directed to identify new strategies for its early detection. MicroRNAs (miRNAs) are a new promising class of circulating biomarkers for cancer detection, but lack of consensus on data normalization methods has affected the diagnostic potential of circulating miRNAs. There is a growing interest in techniques that allow an absolute quantification of miRNAs which could be useful for early diagnosis. Recently, digital PCR, mainly based on droplets generation, emerged as an affordable technology for precise and absolute quantification of nucleic acids.

Novel method to detect microRNAs using chip-based QuantStudio 3D digital PCR.

Lung cancer is the most frequent cause of cancer-related death worldwide, with limited therapeutic options and rapid development of drug resistance. MicroRNAs, a class of small non-coding RNAs that control different physiological processes, have been associated with cancer development, as either oncomiRNAs or tumor-suppressor miRNAs. In the present study we investigated the interaction between mir-486-5p and mir-660-5p, two independent tumor-suppressor miRNAs, to assess their possible role and synergistic effect in lung cancer treatment. Our data show that mir-660-5p over-expression in A549 lung cancer cells induced a remarkable increase in mir-486-5p expression level and activity, detected as a reduction of its target gene, p85. mir-486-5p expression was confirmed by microRNA in situ hybridization. mir-660-5p modulated mir-486-5p through the silencing of Mouse Double Minute 2 (MDM2), one of its direct target, and then through p53 stimulation. This regulatory pathway was effective in A549, but not in H1299; therefore, only in the context of a functional p53 protein. Our findings support the conclusion that mir-486-5p is positively regulated by mir-660-5p in lung cancer cell lines, through the mir-660-MDM2-p53 pathway, making mir-660-5p even more interesting for its potential successful use in lung cancer therapy.

mir-660-p53-mir-486 Network: A New Key Regulatory Pathway in Lung Tumorigenesis.

The issue of overdiagnosis in low-dose computed tomography (LDCT) screening trials could be addressed by the development of complementary biomarkers able to improve detection of aggressive disease. The mutation profile of LDCT screening-detected lung tumors is currently unknown.

Mutational Profile from Targeted NGS Predicts Survival in LDCT Screening-Detected Lung Cancers.

Digital PCR (dPCR) is an innovative approach for detection and quantification of nucleic acid that offers an alternative method to conventional real-time quantitative PCR for absolute quantification. dPCR is a highly precise and sensitive technique that does not require a standard reference, making it a suitable method for the detection of microRNAs. The potential of these small noncoding RNA as biomarkers is on the rise, especially due to their presence in body fluids, making them easily accessible. Nevertheless, the problem of lack of consensus regarding an optimal method for miRNAs normalization compromises their use. Here, we describe an innovative method for the absolute quantification of miRNAs across different types of biological samples using a chip-based platform, the QuantStudio 3D digital PCR.

Detection of microRNAs Using Chip-Based QuantStudio 3D Digital PCR.

Despite many years of research efforts, lung cancer still remains the leading cause of cancer deaths worldwide. Objective of this study was to set up a platform of non-small cell lung cancer patient derived xenografts (PDXs) faithfully representing primary tumour characteristics and offering a unique tool for studying effectiveness of therapies at a preclinical level. We established 38 PDXs with a successful take rate of 39.2%. All models closely mirrored parental tumour characteristics although a selective pressure for solid patterns, vimentin expression and EMT was observed in several models. An increased grafting rate for tumours derived from patients with worse outcome (p = 0.006), higher stage (p = 0.038) and higher CD133(+)/CXCR4(+)/EpCAM(-) stem cell content (p = 0.019) was observed whereas a trend towards an association with SUVmax higher than 8 (p = 0.084) was detected. Kaplan Meier analyses showed a significantly worse (p = 0.0008) overall survival at 5 years in patients with grafted vs not grafted PDXs also after adjusting for tumour stage. Moreover, for 63.2% models, grafting was reached before clinical recurrence occurred. Our findings strengthen the relevance of PDXs as useful preclinical models closely reflecting parental patients tumours and highlight PDXs establishment as a functional testing of lung cancer aggressiveness and personalized therapies.

Article	Year
Novel method to detect microRNAs using chip-based QuantStudio 3D digital PCR. BMC genomics\| PubMed ID: 26493562	2015
mir-660-p53-mir-486 Network: A New Key Regulatory Pathway in Lung Tumorigenesis. International journal of molecular sciences\| PubMed ID: 28124991	2017
Mutational Profile from Targeted NGS Predicts Survival in LDCT Screening-Detected Lung Cancers. Journal of thoracic oncology : official publication of the International Association for the Study of Lung Cancer\| PubMed ID: 28302568	2017
Detection of microRNAs Using Chip-Based QuantStudio 3D Digital PCR. Methods in molecular biology (Clifton, N.J.)\| PubMed ID: 28439837	2017
Establishment of patient derived xenografts as functional testing of lung cancer aggressiveness. Scientific reports\| PubMed ID: 28751748	2017

Cristina Borzi

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