Clinical verification of vimentin/EpCAM immunolipid magnetic sorting system in monitoring CTCs in arterial and venous blood of advanced tumor

Immunolipid magnetic bead-based circulating tumor cell sorting: a novel approach for pathological staging of colorectal cancer

Objective

This study aimed to assess whether circulating tumor cells (CTCs) from colorectal cancer (CRC) could be used as an alternative to tissue samples for genetic mutation testing, overcoming the challenge of difficult tumor tissue acquisition.

Methods

We developed an immunolipid magnetic bead (IMB) system modified with antibodies against epithelial cell adhesion molecule (EpCAM) and vimentin to efficiently separate CTCs. We prepared EpCAM-modified IMBs (Ep-IMBs) and vimentin-modified IMBs (Vi-IMBs). The separation efficiency of the system was evaluated via in vitro experiments and by capturing and counting CTCs in blood samples from 23 CRC patients and 20 healthy controls. Hotspot mutations in patient tissue samples were identified via next-generation sequencing (NGS), whereas mutations in blood CTCs were detected via Sanger sequencing. The concordance between hotspot mutations in tumor tissue and blood CTCs was analyzed.

Results

The CTC sorting system exhibited good dispersion, stability, and low cytotoxicity, with a specificity of 90.54% and a sensitivity of 89.07%. CRC patients had an average of 8.39 CTCs per 7.5 mL of blood, whereas healthy controls had 0.09 per 7.5 mL of blood. The consistency of gene mutations was as follows: TP53 (91.31%), PIK3CA (76.00%), KRAS (85.36%), BRAF (51.00%), APC (65.67%), and EGFR (74.00%), with an overall gene mutation consistency of 85.06%.

Conclusion

Our CTC sorting system, which is based on Ep-IMBs and Vi-IMBs, effectively captures CTCs in the peripheral blood of CRC patients and enables clinical hotspot gene mutation testing via these enriched CTCs. This system partially solves the problem of difficult tumor tissue sample collection and provides a reference for gene mutation testing in early diagnosis, therapeutic efficacy evaluation, prognosis assessment, and minimal metastasis detection in CRC patients, showing significant potential for clinical application, especially in targeted therapy gene testing for CRC.

Detection and Characterization of Circulating Tumor Cells in Colorectal Cancer Patients via Epithelial-Mesenchymal Transition Markers

Background/Objectives: Liquid biopsy methods have gained prominence as minimally invasive tools to improve cancer treatment outcomes. Circulating tumor cells (CTCs) offer valuable insights into both primary and metastatic lesions. However, validating the CTC test results requires confirmation that the detected cells originate from cancer tissue. While studies have identified CTCs in colorectal cancer (CRC) patients using molecular markers, simultaneous validation of their cancer tissue origin remains unexplored. Methods: This study introduces a simple approach to detect adenomatous polyposis coli (APC) gene abnormalities alongside established CTC markers using a molecular imaging flow cytometer (MI-FCM). Given that APC gene abnormalities occur in 60-70% of CRC patients, their detection serves as strong evidence of cancer origin. Results: Our method achieved 92% concordance with DNA sequence analysis of tumor-derived cells. In a proof-of-concept study using 5 mL of whole blood from CRC patients, we observed a high frequency of cells exhibiting APC abnormalities, cytokeratin (CK), and vimentin (Vim) expression. Extending the study to 80 CRC patients across pathological stages I-IV confirmed CK and Vim as valid CTC markers. Three distinct cell populations were identified in blood: CK+/Vim-, CK+/Vim+, and CK-/Vim+. CTC number and frequency increased progressively with cancer stage. Conclusions: This is the first report demonstrating CK and Vim as effective markers for direct CTC detection in CRC patients. Our findings provide evidence-based validation of CTC markers, offering new insights and advancing approaches for patient care.

The Role of Epithelial Cell Adhesion Molecule Cancer Stem Cell Marker in Evaluation of Hepatocellular Carcinoma

Background and Objectives: Hepatocellular carcinoma (HCC) is a prevalent form of malignancy that is characterized by high mortality rates and prognosis that remain suboptimal, largely due to treatment resistance mechanisms. Recent studies have implicated cancer stem cells (CSCs), particularly those expressing epithelial cell adhesion molecule (EpCAM), in HCC progression and resistance. In the present study, we sought to assess EpCAM expression in HCC patients and its correlation with various clinicopathological parameters. Materials and Methods: Tissue samples from 42 HCC patients were subjected to immunohistochemical staining to evaluate EpCAM expression. Clinicopathological data were obtained including the size, grade and stage of tumors, vascular invasion status, alpha-fetoprotein levels, and cirrhosis status. The Chi square and Fisher's exact tests were employed to assess the association between categorical groups. Independent Student-t test or Mann-Whitney U test was used to investigate the association between continuous patient characteristics and survival. Results: Immunohistochemical analysis revealed EpCAM expression in 52.5% of HCC cases. EpCAM-positive tumors exhibited characteristics indicative of aggressive disease, including larger tumor sizes (p = 0.006), greater tumor multiplicity (p = 0.004), higher grades (p = 0.002), more advanced stages (p = 0.003), vascular invasion (p = 0.023), elevated alpha-fetoprotein levels (p = 0.013), and cirrhosis (p = 0.052). Survival analysis demonstrated that EpCAM expression was significantly associated with lower overall rates of survival and higher rates of recurrence in HCC patients. Conclusions: Our findings suggest that EpCAM expression may serve as a prognostic biomarker for HCC with a potential role in patient management. Targeting EpCAM-positive CSCs may represent a promising approach to overcome treatment resistance and improve clinical outcomes in HCC. However, further investigation into the molecular mechanisms underlying EpCAM's role in HCC progression is warranted to facilitate the development of personalized therapeutic interventions.

Circulating tumor cell-derived exosome-transmitted long non-coding RNA TTN-AS1 can promote the proliferation and migration of cholangiocarcinoma cells

BACKGROUND

Exosomes assume a pivotal role as essential mediators of intercellular communication within tumor microenvironments. Within this context, long noncoding RNAs (LncRNAs) have been observed to be preferentially sorted into exosomes, thus exerting regulatory control over the initiation and progression of cancer through diverse mechanisms.

RESULTS

Exosomes were successfully isolated from cholangiocarcinoma (CCA) CTCs organoid and healthy human serum. Notably, the LncRNA titin-antisense RNA1 (TTN-AS1) exhibited a conspicuous up-regulation within CCA CTCs organoid derived exosomes. Furthermore, a significant elevation of TTN-AS1 expression was observed in tumor tissues, as well as in blood and serum exosomes from patients afflicted with CCA. Importantly, this hightened TTN-AS1 expression in serum exosomes of CCA patients manifested a strong correlation with both lymph node metastasis and TNM staging. Remarkably, both CCA CTCs organoid-derived exosomes and CCA cells-derived exosomes featuring pronounced TTN-AS1 expression demonstrated the capability to the proliferation and migratory potential of CCA cells. Validation of these outcomes was conducted in vivo experiments.

CONCLUSIONS

In conclusion, our study elucidating that CCA CTCs-derived exosomes possess the capacity to bolster the metastasis tendencies of CCA cells by transporting TTN-AS1. These observations underscore the potential of TTN-AS1 within CTCs-derived exosomes to serve as a promising biomarker for the diagnosis and therapeutic management of CCA.

Investigating the role of circulating tumor cells in gastric cancer: a comprehensive systematic review and meta-analysis

Investigating the role of circulating tumor cells (CTCs) and their characteristics is still controversial in patients with gastric cancer (GC). Therefore, in this study, to provide a comprehensive review and meta-analyses of the literature on association of CTCs with gastric cancer, Scopus, Web of Science, Embase, and Medline were searched for systematic reviews and meta-analyses conducted during February 2022 using the keywords. Risk of bias, hazard ratios (HRs), and risk differences (RD) were assessed. Forty-five studies containing 3,342 GC patients from nine countries were assessed. The overall prevalence of CTC in GC was 69.37% (60.27, 77.78). The pooled result showed that increased mortality in GC patients was significantly associated with positive CTCs, poor overall survival (HR = 2.73, 95%CI 2.34-3.24, p < 0.001), and progression-free survival rate (HR = 2.78, 95%CI 2.01-3.85, p < 0.001). Subgroup analyses regarding markers, detection methods, treatment type, presence of distance metastasis, presence of lymph node metastasis, and overall risk of bias showed significant associations between the groups in terms of the incidence rates of CTCs, OS, and PFS. In addition, the results of risk differences based on sampling time showed that the use of the cell search method (RD: - 0.19, 95%CI (- 0.28, - 0.10), p < 0.001), epithelial marker (RD: - 0.12, 95%CI (- 0.25, 0.00), p 0.05) and mesenchymal markers (RD: - 0.35, 95%CI (- 0.57, - 0.13), p 0.002) before the treatment might have a higher diagnostic power to identify CTCs and also chemotherapy treatment (RD: - 0.17, 95%CI (- 0.31, - 0.03), p 0.016) could significantly reduce the number of CTCs after the treatment. We also found that the risk differences between the clinical early and advanced stages were not statistically significant (RD: - 0.10, 95%CI (- 0.23, 0.02), P 0.105). Also, in the Lauren classification, the incidence of CTC in the diffuse type (RD: - 0.19, 95%CI (- 0.37, - 0.01), P0.045) was higher than that in the intestinal type. Meta-regression analysis showed that baseline characteristics were not associated with the detection of CTCs in GC patients. According to our systematic review and meta-analysis, CTCs identification may be suggested as a diagnostic technique for gastric cancer screening, and the outcomes of CTC detection may also be utilized in the future to create personalized medicine programs.

Feasibility study of expressing epcam + /vimentin + CTC in prostate cancer diagnosis

PURPOSE

Prostate cancer (PCa) is one of the most common malignancies in men and one of the leading causes of cancer-related deaths; circulating tumor cells (CTC) are malignant cells that have broken off from original tumor or metastatic sites and extravasated into the blood vessels either naturally or maybe as a consequence of surgical procedures. This study aims to explore the feasibility of liquid biopsy technique to diagnose prostate cancer.

METHOD

We constructed an assay platform integrating magnetic separation and fluorescence in situ hybridization (FISH) to effectively capture prostate cancer CTCs and evaluate the distribution between healthy volunteers and prostate cancer patients, respectively.

RESULTS

There was a significant difference in the number of CTCs between the healthy population and prostate cancer patients (P < 0.001). The results of the study showed that the CTCs capture identification system has good sensitivity and specificity in identifying prostate cancer patients.

CONCLUSION

The CTCs test allows us to accurately identify patients who are at high risk for prostate cancer, allowing for early intervention and treating patients effectively.

Exosomal proteomics identifies RAB13 as a potential regulator of metastasis for HCC

BACKGROUND

Exosomal proteins from cancer cells are becoming new biomarkers for cancer monitoring and efficacy evaluation. However, their biological function and molecular mechanism underlying tumor metastasis are largely unknown.

METHODS

Bioinformatic methods such as bulk gene expression analysis, single-cell RNA sequencing data analysis, and gene set enrichment analysis were employed to identify metastasis-associated proteins. The in vitro and in vivo experiments were used to investigate the function of RAB13 in HCC metastasis.

RESULTS

We identified RAB13 as one of the critical regulators of metastasis in HCC-derived exosomes for the first time. In vitro, the invasiveness of HCC cell lines could be attenuated by RAB13 silence. In vivo, tumor size and proportion of high-grade lung metastatic nodule could be reduced in the mice with orthotopic transplantation of tumors and intravenously injected with exosomes derived from MHCC97H cell with RAB13 silence (si-RAB13-Exo), as compared with those without RAB13 silence (si-NC-Exo). Moreover, in si-RAB13-Exo group, circulating tumor cell counts were decreased at the third, fourth, and fifth weeks after orthotopic transplantation of tumors, and MMP2 (matrix metalloproteinase 2)/TIMP2 (tissue inhibitor of metalloproteinases 2) ratio was also significantly decreased. In addition, RAB13 expression was also associated with VEGF levels, microvessel density, and tube formation of vascular endothelial cells by both in vitro and in vivo models, indicating that RAB13 was associated with angiogenesis in HCC.

CONCLUSIONS

We have demonstrated exosomal RAB13 as a potential regulator of metastasis for HCC by in silico, in vitro, and in vivo methods, which greatly improve our understanding of the functional impact of exosomal proteins on HCC metastasis.

Understanding the versatile roles and applications of EpCAM in cancers: from bench to bedside

Epithelial cell adhesion molecule (EpCAM) functions not only in physiological processes but also participates in the development and progression of cancer. In recent decades, extensive efforts have been made to decipher the role of EpCAM in cancers. Great advances have been achieved in elucidating its structure, molecular functions, pathophysiological mechanisms, and clinical applications. Beyond its well-recognized role as a biomarker of cancer stem cells (CSCs) or circulating tumor cells (CTCs), EpCAM exhibits novel and promising value in targeted therapy. At the same time, the roles of EpCAM in cancer progression are found to be highly context-dependent and even contradictory in some cases. The versatile functional modules of EpCAM and its communication with other signaling pathways complicate the study of this molecule. In this review, we start from the structure of EpCAM and focus on communication with other signaling pathways. The impacts on the biology of cancers and the up-to-date clinical applications of EpCAM are also introduced and summarized, aiming to shed light on the translational prospects of EpCAM.

Research on the Construction of Bispecific-Targeted Sustained-Release Drug-Delivery Microspheres and Their Function in Treatment of Hepatocellular Carcinoma

Lenvatinib (LEN) is approved as one of the commonly used drugs in the treatment of hepatocellular carcinoma (HCC). It is recognized to be a novel therapeutic choice for the direct and targeted delivery of effective drugs to HCC tumor sites. The key to the proposed method lies in the requirement for efficient targeted drug delivery carriers with targeting performance to deliver effective drugs directly and safely to tumor lesions. Methods: Here, magnetic liposomes (MLs) were modified by phosphatidylinositol proteoglycan 3 (GPC3) and epithelial cell adhesion molecules (EpCAMs). Subsequently, bispecific-targeted sustained-release drug-loaded microspheres containing LEN (GPC3/EpCAM-LEN-MLs) were constructed. In addition, both cytotoxicity and magnetic resonance imaging (MRI) analyses were performed to establish a mouse model and further perform corresponding performance assessments. Results: The corresponding results showed that GPC3/EpCAM-LEN-MLs were spherical-shaped and evenly dispersed. The encapsulation and drug-loading efficiencies were 91.08% ± 1.83% and 8.22% ± 1.24%, respectively. Meanwhile, GPC3/EpCAM-LEN-MLs showed a high inhibition rate on the proliferation of HCC cells and significantly increased their apoptosis. Furthermore, MRI revealed that the system possessed the function of tracking and localizing tumor cells, and animal experiments verified that it could exert the function of disease diagnosis. Conclusions: Our experiments successfully constructed a safe and efficient bispecific-targeted sustained-release drug delivery system for HCC tumor cells. It provides a useful diagnostic and therapeutic scheme for the clinical diagnosis and targeted therapy of HCC. Moreover, it can be used as a potential tumor-specific MRI contrast agent for the localization and diagnosis of malignant tumors.