Cancer Genetics and Epigenetics 2024, Vol.12, No.5, 254-269 http://medscipublisher.com/index.php/cge 258 Figure 1 Colorectal cancer development, CTC formation, and their distant spread and cluster composition a,the development process of colon cancer is divided into four stages.stage 0 to 1: The tumor is confined to the mucosa of the large intestine, forming polyps and spreading between the mucosa and muscle layer.stage 2: The tumor invades between the muscle layer and the serosal layer.stage 3: The tumor spreads through the serous membrane and metastasizes to nearby lymph nodes.stage 4: The tumor metastasizes to other organs, such as the brain, stomach, liver, or lungs.b,the multistep process of cancer metastasis involves tumor cell invasion at the primary site, intravasation into circulation, survival and interaction with blood cells as circulating tumor cells (CTCs), extravasation from the bloodstream, and colonization of the metastatic site.c,CTC clusters are made of cancer cells and non-cancerous stromal or immune cells bind through intracel lular junctions,including T cells, macrophages, white blood cells, fibroblasts, neutrophils, and platelets. 4.1.2 Molecular assays Molecular assays, including polymerase chain reaction (PCR) and next-generation sequencing (NGS), offer a highly sensitive approach to detecting CTCs by targeting specific genetic mutations and gene expressions associated with cancer. These techniques can identify CTCs based on the presence of tumor-specific DNA or RNA sequences, providing a detailed molecular profile of the cancer. The analysis of circulating tumor DNA (ctDNA) and other genetic markers in blood samples has shown great potential in early cancer detection, monitoring treatment response, and predicting disease recurrence (Marcuello et al., 2019). However, the rarity of CTCs in the bloodstream poses a significant challenge, requiring highly sensitive and specific assays to accurately detect and quantify these cells (Paterlini-Bréchot and Benali, 2007; Marcuello et al., 2019). 4.1.3 Microfluidic technologies Microfluidic technologies have revolutionized the isolation and detection of CTCs by offering a high-throughput, cost-effective, and precise method for capturing these rare cells from blood samples. These systems utilize the unique physical and biological properties of CTCs, such as size, deformability, and surface markers, to separate them from other blood components. Microfluidic devices, such as the CTC-chip, employ antibody-coated microposts to selectively capture CTCs under controlled flow conditions, achieving high sensitivity and specificity (Nagrath et al., 2007). Other microfluidic platforms leverage hydrodynamic size-based sorting and inertial lift forces to isolate CTCs without the need for pre-labeling or extensive sample processing (Warkiani et al., 2014; Jiang et al., 2017). The integration of microfluidic technologies with downstream molecular and immunological analyses enables comprehensive characterization of CTCs, enhancing our understanding of their role in cancer metastasis and improving non-invasive diagnostic capabilities (Qian et al., 2015; Jackson; et al., 2017; Jiang et al., 2017; Farshchi and Hasanzadeh, 2020; Li et al., 2020).
RkJQdWJsaXNoZXIy MjQ4ODYzNQ==