Liquid Biopsies in Cancer Diagnosis, Monitoring and Prognosis

High-precision extracellular-vesicle isolation-analysis integrated platform for rapid cancer diagnosis directly from blood plasma

Cancer-derived small extracellular vesicles (sEVs) in body fluids hold promise as biomarkers for cancer diagnosis. For sEV-based liquid biopsy, isolation of sEVs with a high-purity and cancer-sEV detection with an extremely high sensitivity are essential because body fluids include much higher density of normal-cell-derived sEVs and other biomolecules and bioparticles. Here, we propose an isolation-analysis-integrated cancer-diagnosis platform based on dielectrophoresis(DEP)-ELISA technique which enables a three orders of magnitude higher sensitivity over conventional ELISA method and direct cancer diagnosis from blood plasma with high accuracy. The limit of detection (LOD) for sEVs in human plasma was as low as 104 sEVs/mL without a time-consuming and low-yield sEV isolation and purification process. The capability of this platform was validated by monitoring mice with cancer cell inoculation and assessing the effect of cancer-sEV-inhibiting drug. Using the developed sEV-based liquid biopsy, we diagnosed clinical samples from healthy donors (N = 39) and cancer patients (N = 90). The diagnostic accuracy was 94.2%, 98.6%, and 91.3% for breast, colon, and lung cancers, respectively. This integrated sEV isolation and analysis platform could be applied for high-sensitivity biomarker profiling and sEV-based liquid biopsy.

Detection of circulating tumor cells in peripheral blood of patients with tongue squamous cell carcinoma and its relationship with clinical features and prognosis: a retrospective study

BACKGROUND

Circulating tumor cells (CTCs) are a promising biomarker for assessment of prognosis. The study was to analyse the relationship between preoperative and postoperative peripheral blood CTC and clinical features and prognosis in patients with tongue squamous cell carcinoma (TSCC).

METHODS

85 with TSCC and 30 tongues with benign disease who underwent surgical treatment from May 2016 to May 2023 were retrospectively analysed. CTC testing was performed twice for TSCC group before and after surgery and only before the surgery for the benign disease group, only one test was performed before surgery.The association of CTCs with clinical features and progression-free survival (PFS) was also analyzed.

RESULTS

The positive rates of CTCs in patients with TSCC were 90.6% before treatment and 72.9% after treatment, respectively. CTCs were not detected in patients with benign disease group before treatment. There was no significant difference in the number of CTCs before and after treatment in patients with disease progression (P > 0.05). However, the number of CTCs after treatment in patients with disease remission (DR) and stable disease (SD) was significantly lower than before treatment, and the difference was statistically significant (P < 0.05). The results of the log-rank test demonstrated that the postoperative CTC was associated with the PFS (P < 0.05), whereas the preoperative CTC was not related to the PFS. The Cox proportional hazard regression model indicated that postoperative CTC and lymph node metastasis were independent risk factors.

CONCLUSIONS

Postoperative CTCs may be an independent risk factor for a poor prognosis in patients with TSCC and CTC may serve as a valuable biomarker for prognostic monitoring for TSCC patients.

Microbiome and lung cancer: carcinogenic mechanisms, early cancer diagnosis, and promising microbial therapies

Microbiomes in the lung, gut, and oral cavity are correlated with lung cancer initiation and progression. While correlations have been preliminarily established in earlier studies, delving into microbe-mediated carcinogenic mechanisms will extend our understanding from correlation to causation. Building upon the causative relationships between microbiome and lung cancer, a novel concept of microbial biomarkers has emerged, mainly encompassing cancer-specific bacteria and circulating microbiome DNA. They might function as noninvasive liquid biopsy techniques for lung cancer early detection. Furthermore, potential microbial therapies have displayed initial efficacy in lung cancer treatment, providing multiple avenues for therapeutic intervention. Herein, we will discuss the molecular mechanisms and signaling pathways through which microbes influence lung cancer initiation and development. Additionally, we will summarize recent findings on microbial biomarkers as a member of tumor liquid biopsy techniques and provide an overview of the latest advances in various microbe-assisted/mediated therapeutic approaches for lung cancer.

Prostate cancer-derived small extracellular vesicle proteins: the hope in diagnosis, prognosis, and therapeutics

Current diagnostic tools for prostate cancer (PCa) diagnosis and risk stratification are insufficient. The hidden onset and poor efficacy of traditional therapies against metastatic PCa make this disease a heavy burden in global men's health. Prostate cancer-derived extracellular vesicles (PCDEVs) have garnered attention in recent years due to their important role in communications in tumor microenvironment. Recent advancements have demonstrated PCDEVs proteins play an important role in PCa invasion, progression, metastasis, therapeutic resistance, and immune escape. In this review, we briefly discuss the applications of sEV proteins in PCa diagnosis and prognosis in liquid biopsy, focus on the roles of the PCa-derived small EVs (sEVs) proteins in tumor microenvironment associated with cancer progression, and explore the therapeutic potential of sEV proteins applied for future metastatic PCa therapy.