Molecular Approaches to Metastatic Colorectal Cancer: Better Diagnosis - Better Treatment?

Colorectal Cancer: Genetic Underpinning and Molecular Therapeutics for Precision Medicine

Colorectal cancer (CRC) accounts for about 10% of all cancer cases and 9% of cancer-related deaths globally. In the United States alone, CRC represents approximately 12.6% of all cancer cases, with a mortality rate of about 8%. CRC is now the first leading cause of cancer death in men younger than age 50 and second in women younger than age 50. This review delves into the genetic landscape of CRC, highlighting key mutations and their implications in disease progression and treatment. We provide an overview of the current and emerging therapeutic strategies tailored to individual genomic profiles.

Emerging Roles of Small Extracellular Vesicles in Gastrointestinal Cancer Research and Therapy

Discovered in the late eighties, sEVs are small extracellular nanovesicles (30-150 nm diameter) that gained increasing attention due to their profound roles in cancer, immunology, and therapeutic approaches. They were initially described as cellular waste bins; however, in recent years, sEVs have become known as important mediators of intercellular communication. They are secreted from cells in substantial amounts and exert their influence on recipient cells by signaling through cell surface receptors or transferring cargos, such as proteins, RNAs, miRNAs, or lipids. A key role of sEVs in cancer is immune modulation, as well as pro-invasive signaling and formation of pre-metastatic niches. sEVs are ideal biomarker platforms, and can be engineered as drug carriers or anti-cancer vaccines. Thus, sEVs further provide novel avenues for cancer diagnosis and treatment. This review will focus on the role of sEVs in GI-oncology and delineate their functions in cancer progression, diagnosis, and therapeutic use.

Consensus molecular subtypes of colorectal cancer in clinical practice: A translational approach

The identification of several genetic mutations in colorectal cancer (CRC) has allowed a better comprehension of the prognosis and response to different antineoplastic treatments. Recently, through a systematic process, consensus molecular subtypes (CMS) have been described to characterize genetic and molecular mutations in CRC patients. Through CMS, CRC patients can be categorized into four molecular subtypes of CRC by wide transcriptional genome analysis. CMS1 has microsatellite instability and mutations in CIMP and BRAF pathways. CMS2, distinguished by mutations in specific pathways linked to cellular metabolism, also has a better prognosis. CMS3 has a KRAS mutation as a hallmark. CMS4 presents mutations in fibrogenesis pathways and mesenchymal-epithelial transition, associated with a worse prognosis. CMS classification can be a meaningful step in providing possible answers to important issues in CRC, such as the use of adjuvant chemotherapy in stage II, personalized first-line chemotherapy for metastasic CRC, and possible new target treatments that address specific pathways in each molecular subtype. Understanding CMS is a crucial step in personalized medicine, although prospective clinical trials selecting patients by CMS are required to pass proof-of-concept before becoming a routine clinical tool in oncology routine care.

Circular RNA circ_0000372 contributes to the proliferation, migration and invasion of colorectal cancer by elevating IL6 expression via sponging miR-495

Circular RNAs are thought to play a vital function in the progression of various cancers, including colorectal cancer (CRC). However, the biological function and mechanism of circ_0000372 in CRC are still not clear. The expression of circ_0000372 and microRNA (miR)-495 was examined by quantitative real-time PCR. Cell proliferation was evaluated using cell counting kit 8 and colony formation assays. Further, cell migration and invasion were assessed using transwell assay. Additionally, western blot analysis was used to detect the expression of proteins associated with proliferation, metastasis, Janus kinase 2 (JAK2)/signal transducers and activators of transcription (STAT3) signaling pathway and interleukin 6 (IL6). Dual-luciferase reporter assay and RNA immunoprecipitation assay were employed to verify the interaction between miR-495 and circ_0000372 or IL6. Furthermore, the effect of circ_0000372 on CRC tumor growth in vivo was explored using the mice xenograft models. Circ_0000372 was markedly upregulated in CRC, and its high expression was associated with the poor prognosis of CRC patients. Silenced circ_0000372 was able to suppress CRC cell proliferation, migration and invasion in vitro and CRC tumor growth in vivo. Bioinformatics prediction and experimental verification proposed that circ_0000372 could sponge miR-495, and miR-495 could target IL6. Besides, the JAK2/STAT3 signaling pathway activation could be regulated by circ_0000372, miR-495 and IL6. Rescue assay results confirmed that the inhibition effect of circ_0000372 knockdown on the proliferation and metastasis of CRC could be reversed by miR-495 inhibitor or IL6 overexpression. In short, we concluded that circ_0000372 promoted CRC progression by regulating the miR-495/IL6 axis, suggesting that circ_0000372 could be used as a new prognostic biomarker and therapeutic target for CRC.