Plasma exosomal hsa_circ_0079439 as a novel biomarker for early detection of gastric cancer

Emerging roles of circular RNAs in tumorigenesis, progression, and treatment of gastric cancer

With an estimated one million new cases reported annually, gastric cancer (GC) ranks as the fifth most diagnosed malignancy worldwide. The early detection of GC remains a major challenge, and the prognosis worsens either when patients develop resistance to chemotherapy or radiotherapy or when the cancer metastasizes. The precise pathogenesis underlying GC is not well understood, which further complicates its treatment. Circular RNAs (circRNAs), a recently discovered class of noncoding RNAs that originate from parental genes through "back-splicing", have been shown to play a key role in various biological processes in both eukaryotes and prokaryotes. CircRNAs have been linked to cardiovascular diseases, diabetes, hypertension, Alzheimer's disease, and the occurrence and progression of tumors. Prior studies have established that circRNAs play a crucial role in GC, impacting tumorigenesis, diagnosis, progression, and therapy resistance. This review aims to summarize how circRNAs contribute to GC tumorigenesis and progression, examine their roles in the development of drug resistance, discuss their potential as biotechnological drugs, and summarize their response to therapeutic drugs and microorganism in GC.

Exosomal circRNAs in gastrointestinal cancer: Role in occurrence, development, diagnosis and clinical application (Review)

Gastrointestinal cancer is frequently detected at an advanced stage and has an undesirable prognosis due to the absence of efficient and precise biomarkers and therapeutic targets. Exosomes are small, living‑cell‑derived vesicles that serve a critical role in facilitating intercellular communication by transporting molecules from donor cells to receiver cells. circular RNAs (circRNAs) are mis‑expressed in a variety of diseases, including gastrointestinal cancer, and are promising as diagnostic biomarkers and tumor therapeutic targets for gastrointestinal cancer. The main features of exosomes and circRNAs are discussed in the present review, along with research on the biological function of exosomal circRNAs in the development and progression of gastrointestinal cancer. It also assesses the advantages and disadvantages of implementing these findings in clinical applications.

Comprehensive evaluation of serum circHAS2 as a novel diagnostic and prognostic biomarker for gastric cancer

The diagnosis and screening indicators for gastric cancer (GC) are not satisfactory, resulting in a large number of GC patients being missed and missing the best treatment time. Due to the special structure of circular RNAs (circRNAs), they have a more accurate and powerful ability to detect tumor occurrence. In addition, circHAS2 has been found to promote the proliferation, migration, and invasion of GC cells. Therefore, this study explored the potential of circHAS2 as a biomarker for GC. The expression level of circHAS2 in the specimens was detected by real-time fluorescent quantitative PCR. The molecular characteristics of circHAS2 were verified by agarose gel electrophoresis and Sanger sequencing. The feasibility of the circHAS2 detection method was verified by room temperature placement and repeated freezing and thawing. The diagnostic effect of circHAS2 on GC was evaluated by receiver-operating curve analysis. The correlation between circHAS2 expression level and clinical pathological parameters was analyzed using the χ2 -test. Kaplan-Meier survival curve analysis was used to analyze the survival situation of the circHAS2 high- and low-expression group. Univariate and multivariate Cox regression analysis was used to evaluate the influencing factors of prognosis in GC patients. CircHAS2 in cells can be secreted into the blood, and its expression level is significantly upregulated in the serum of patients with GC. The expression level of circHAS2 is correlated with the tissue differentiation, tumor node metastasis staging, classification, and lymph node metastasis of GC patients. CircHAS2 can effectively identify GC and even early GC. In addition, the expression levels of circHAS2 in postoperative GC patients significantly decreased and returned to normal after the second stage of chemotherapy. Finally, the circHAS2 low-expression group had better survival. The upregulated expression of circHAS2 in the serum of GC patients can effectively identify GC and early GC and can be used for effective monitoring of the prognosis of GC patients. In summary, circHAS2 can be used as an effective diagnostic and prognostic marker for GC.