Roles of circulating tumor DNA in PD-1/PD-L1 immune checkpoint Inhibitors: Current evidence and future directions

Exosomes in esophageal cancer: a promising frontier for liquid biopsy in diagnosis and therapeutic monitoring

Esophageal cancer is a common and lethal digestive system malignancy, and both treatment efficacy and patient survival rates face significant challenges. In recent years, exosomes have emerged as crucial mediators of intercellular communication, demonstrating tremendous clinical potential, particularly in the diagnosis, treatment, and prognostic evaluation of esophageal cancer. These exosomes not only serve as biomarkers for early diagnosis and prognosis but also modulate tumor growth, metastasis, and drug resistance by delivering bioactive molecules. Importantly, exosomes can act as carriers for esophageal cancer-related therapeutic agents, optimizing gene therapy strategies to enhance efficacy while reducing toxicity and side effects. Despite facing challenges in clinical applications such as purification, enrichment, and standardization of analytical methods, exosomes maintain broad prospects for application in esophageal cancer treatment, with the potential to significantly improve patient outcomes and quality of life. This review focuses on the innovative role of exosomes in the early diagnosis of esophageal cancer, exploring their application value and safety in disease monitoring and assessment of treatment response. Furthermore, this study outlines the challenges and limitations of transitioning exosome research from basic studies to clinical applications, as well as potential solutions and future research directions to address these obstacles.

Omics-based molecular classifications empowering in precision oncology

BACKGROUND

In the past decades, cancer enigmatical heterogeneity at distinct expression levels could interpret disparities in therapeutic response and prognosis. It built hindrances to precision medicine, a tactic to tailor customized treatment informed by the tumors' molecular profile. Single-omics analysis dissected the biological features associated with carcinogenesis to some extent but still failed to revolutionize cancer treatment as expected. Integrated omics analysis incorporated tumor biological networks from diverse layers and deciphered a holistic overview of cancer behaviors, yielding precise molecular classification to facilitate the evolution and refinement of precision medicine.

CONCLUSION

This review outlined the biomarkers at multiple expression layers to tutor molecular classification and pinpoint tumor diagnosis, and explored the paradigm shift in precision therapy: from single- to multi-omics-based subtyping to optimize therapeutic regimens. Ultimately, we firmly believe that by parsing molecular characteristics, omics-based typing will be a powerful assistant for precision oncology.

Predictive biomarkers of colon cancer immunotherapy: Present and future

Immunotherapy has revolutionized colon cancer treatment. Immune checkpoint inhibitors (ICIs) have shown clinical benefits for colon cancer patients, especially those with high microsatellite instability (MSI-H). In 2020, the US Food and Drug Administration (FDA)-approved ICI pembrolizumab as the first-line treatment for metastatic MSI-H colon cancer patients. Additionally, neoadjuvant immunotherapy has presented efficacy in treating early-stage colon cancer patients. Although MSI has been thought of as an effective predictive biomarker for colon cancer immunotherapy, only a small proportion of colon cancer patients were MSI-H, and certain colon cancer patients with MSI-H presented intrinsic or acquired resistance to immunotherapy. Thus, further search for predictive biomarkers to stratify patients is meaningful in colon cancer immunotherapy. Except for MSI, other biomarkers, such as PD-L1 expression level, tumor mutation burden (TMB), tumor-infiltrating lymphocytes (TILs), certain gut microbiota, ctDNA, and circulating immune cells were also proposed to be correlated with patient survival and ICI efficacy in some colon cancer clinical studies. Moreover, developing new diagnostic techniques helps identify accurate predictive biomarkers for colon cancer immunotherapy. In this review, we outline the reported predictive biomarkers in colon cancer immunotherapy and further discuss the prospects of technological changes for biomarker development in colon cancer immunotherapy.