What is Liquid Biopsy?
Cancer detection and monitoring method
Liquid Biopsy, also known as fluid biopsy, is a significant branch of in vitro diagnosis that is primarily based on blood or other body fluid for disease analysis and monitoring, such as cancer. With a simple blood draw, circulating tumor biomarkers in the blood sample provide information on tumor progression and treatment efficacy, and guiding personalized precision medication direction. Compared with traditional tissue biopsy, liquid biopsy has provided additional benefits of real-time monitoring, avoid unrepresentative sampling in heterogenous tumor, and provides comprehensive clinical information.
Liquid Biopsy is a branch of in vitro diagnostics that analyses and diagnoses diseases such as cancer through the use of body liquids like blood or urine. It was rated as one of the “Breakthrough Technologies 2015” by MIT Technology Review.
Compared to traditional tissue biopsy, liquid biopsy is equipped with unique advantages like real-time monitoring, ability to overcome tumor heterogeneity, and comprehensive diagnostic information. Currently, in clinical researches, liquid biosy mainly includes tests for CTC (Circulating Tumor Cell), ctDNA (Circulating Tumor DNA), exosomes, and Circulating miRNA etc. In comparison to traditional methods like observation of clinical symptoms or diagnostic imaging, using liquid biopsy can predict the risk of cancer earlier, enabling “Early discovery, early screening, early treatment”.
What is Circulating miRNA?
microRNAs or miRNAs are small RNA molecules that are non-coding and have important effects on gene expression, often inhibitory. By binding to mRNAs in the cells, the microRNAs inhibit DNA functioning, thus affecting important life functions in a cell. In many cancer types, miRNAs production is upregulated, converting an ordinary cell into a cancerous one. Additionally, these miRNAs can be transported outside the cell, in the tumour environment, in sacs/vesicles called 'exosomes'. The presence of a high number of exosomal miRNAs has been associated with the spread of certain types of cancer in the body. Isolation and detection of miRNAs from a patient’s blood can help in early cancer diagnosis, without the need for invasive surgeries.
What is Circulating Tumor Cell (CTC)?
Circulating tumor cell (CTCs) are the cancer cells that have detached from the primary tumor or metastatic tumor into circulatory system during tumor progression or metastases. CTC provides comprehensive information of cancer in cellular, genetics and protein levels. Hence, CTC detection is an effective tool for earlier detection, evaluation of therapeutic efficacy, individual precision medicine selection, drug resistance detection, earlier tumor recurrence evaluation and real-time monitoring of cancer.
How can we detect CTCs in blood?
Cellomics CTC detection Platform - New generation of CTC viable Cell Sorting.
The CTC detection platform has employed the leading microfluidic chip technology that select CTCs extensively by cell size, cell shape and multiple surface biomarkers. This technology has combined the physical, chemical and biological properties of CTCs to uphold the high sensitivity, high specificity and high accuracy of CTC detection.
What are companion diagnostics?
According to FDA: 'A companion diagnostic is a medical device, often an in vitro device, which provides information that is essential for the safe and effective use of a corresponding drug or biological product.'--These diagnostic tests help determine if patients have certain biological characters that allow them to positively respond to the corresponding drugs, and exclude patients who wont.
Staining Solution C - uses antibody CD45 to distinguish white blood cells and CTCs.
Staining Solution D - uses antibody DAPI to stain cells.
Staining Solution E - uses antibody EpCAM to show the epithelial phenotype of the CTC.
Staining Solution P - uses antibody PD-L1 to identify whether the CTC have PD-L1 antigen
The reagent in this kit is enough for 20 CTC tests.
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The ImmunoDx test can be used find out the whether the CTC has the PD-L1/ PD-1 antigen, helping medical specialists determine whether the patient is suitable for a specific immunotherapy.