Molecular profiles of single circulating tumor cells from early breast cancer patients with different lymph node statuses

Systematic optimization and evaluation of culture conditions for the construction of circulating tumor cell clusters using breast cancer cell lines

BACKGROUND

Circulating tumor cell (CTC) clusters play a critical role in carcinoma metastasis. However, the rarity of CTC clusters and the limitations of capture techniques have retarded the research progress. In vitro CTC clusters model can help to further understand the biological properties of CTC clusters and their clinical significance. Therefore, it is necessary to establish reliable in vitro methodological models to form CTC clusters whose biological characteristics are very similar to clinical CTC clusters.

METHODS

The assays of immunofluorescence, transmission electron microscopy, EdU incorporation, cell adhension and microfluidic chips were used. The experimental metastasis model in mice was used.

RESULTS

We systematically optimized the culture methods to form in vitro CTC clusters model, and more importantly, evaluated it with reference to the biological capabilities of reported clinical CTC clusters. In vitro CTC clusters exhibited a high degree of similarity to the reported pathological characteristics of CTC clusters isolated from patients at different stages of tumor metastasis, including the appearance morphology, size, adhesive and tight junctions-associated proteins, and other indicators of CTC clusters. Furthermore, in vivo experiments also demonstrated that the CTC clusters had an enhanced ability to grow and metastasize compared to single CTC.

CONCLUSIONS

The study provides a reliable model to help to obtain comparatively stable and qualified CTC clusters in vitro, propelling the studies on tumor metastasis.

Expression of PTP4A1 in circulating tumor cells and its efficacy evaluation in patients with early- and intermediate-stage esophageal cancer

The objective of this study is to investigate the expression of protein tyrosine phosphatase type I (PTP4A1) in circulating tumor cells (CTCs) in patients with early- and intermediate-stage esophageal cancer and its clinical value in evaluating patient prognosis. Tissue and peripheral blood samples were collected from patients with esophageal cancer, as well as their clinical data. Follow-up was performed on all patients. PTP4A1 expression in the CTCs of patients were analyzed by regression analysis, and its correlation with the clinical characteristics of esophageal cancer was discussed. The numbers of mixed tumor cells and T-CTCs were significantly correlated with lymph node metastasis. Advanced tumor-node metastasis (TNM) stage (odds ratio = 12.063) and lymph node metastasis (odds ratio = 13.541) were influencing factors of PTP4A1+MCTC expression disorders in patients with esophageal cancer. The receiver operating characteristic curve showed that TNM stage and lymph node metastasis had a high predictive efficiency for PTP4A1+MCTCs, with an area under the ROC curve of 0.725. PTP4A1+mixed tumor cells had strong predictive value for the efficacy of neoadjuvant therapy, with a sensitivity of 94.7% and a specificity of 63.6%. Advanced TNM stage and lymph node metastasis are influencing factors for increased CTCs and poor expression of PTP4A1 in patients with esophageal cancer.

New insights into the correlations between circulating tumor cells and target organ metastasis

Organ-specific metastasis is the primary cause of cancer patient death. The distant metastasis of tumor cells to specific organs depends on both the intrinsic characteristics of the tumor cells and extrinsic factors in their microenvironment. During an intermediate stage of metastasis, circulating tumor cells (CTCs) are released into the bloodstream from primary and metastatic tumors. CTCs harboring aggressive or metastatic features can extravasate to remote sites for continuous colonizing growth, leading to further lesions. In the past decade, numerous studies demonstrated that CTCs exhibited huge clinical value including predicting distant metastasis, assessing prognosis and monitoring treatment response et al. Furthermore, increasingly numerous experiments are dedicated to identifying the key molecules on or inside CTCs and exploring how they mediate CTC-related organ-specific metastasis. Based on the above molecules, more and more inhibitors are being developed to target CTCs and being utilized to completely clean CTCs, which should provide promising prospects to administer advanced tumor. Recently, the application of various nanomaterials and microfluidic technologies in CTCs enrichment technology has assisted to improve our deep insights into the phenotypic characteristics and biological functions of CTCs as a potential therapy target, which may pave the way for us to make practical clinical strategies. In the present review, we mainly focus on the role of CTCs being involved in targeted organ metastasis, especially the latest molecular mechanism research and clinical intervention strategies related to CTCs.