[Enrichment and detection of circulating tumor cells and its application in head and neck squamous cell carcinoma]

A pilot study of the relative number of circulating tumor cells and leukocytes containing actin-binding proteins in head and neck cancer patients

Circulating tumor cells (CTCs) play an important role in tumor metastases, which is positively correlated with an increased risk of death. Actin-binding proteins, including cofilin (CFL1), profilin 1 (PFN1), and adenylate cyclase-associated protein 1 (CAP1), are thought to be involved in tumor cell motility and metastasis, specifically in head and neck squamous cell carcinoma (HNSCC). However, currently, there are no published studies on CFL1, PFN1, and CAP1 in CTCs and leukocytes in HNSCC patients. We assessed serum levels of CFL1, PFN1, and CAP1 and the number of CTCs and leukocytes containing these proteins in blood from 31 HNSCC patients (T1-4N0-2M0). The analysis used flow cytometry and an enzyme-linked immunosorbent assay kit. We found that CAP1 + CTCs and CAP1 + leukocyte subpopulations were prevalent in these HNSCC patient samples, while the prevalence rates of CFL1 + and PFN1 + CTCs were relatively low. Patients with stage T2-4N1-2M0 had CFL1 + and PFN1 + CTCs with an elevated PFN1 serum level, compared with the T1-3N0M0 group. In summary, the PFN1 serum level and the relative number of PFN1 +CD326 + CTCs could be valuable prognostic markers for HNSCC metastases. The current study is the first to obtain data regarding the contents of actin-binding proteins (ABPs) in CTCs, and leukocytes in blood from HNSCC patients. This is also the first to assess the relationship between the number of CTCs subgroups and disease characteristics.

Clinical significance of circulating tumor cells in patients with locally advanced head and neck squamous cell carcinoma

The present study aimed to investigate the clinical relevance of circulating tumor cells (CTCs) in patients with locally advanced head and neck squamous cell carcinoma (LA‑HNSCC), particularly in patients with nasopharyngeal and hypopharyngeal squamous cell carcinoma. CTCs were isolated using negative immunomagnetic bead enrichment and were identified by fluorescence in situ hybridization. Youden's index and the receiver operating characteristic (ROC) curve were used to select the optimal CTC baseline value. χ2 test or Fisher's test were used to determine the association between CTC counts and clinical parameters, curative effects and prognosis. The Kaplan‑Meier estimator was used to analyze overall survival (OS) and progression‑free survival (PFS). In the present study, 356 peripheral blood samples (178 pretreatment samples and 178 post‑treatment samples) from 178 patients were examined. The results revealed that the pretreatment CTC detection rate was 73.8%. The minimum, maximum and median CTC counts were 1, 22 and 2/3.2 ml, respectively. The number of polyploid CTCs was associated with distant metastasis (P=0.026). In addition, patients with undetectable CTCs, and decreasing or negative CTCs post‑treatment tended to have a good prognosis (P<0.05). For nasopharyngeal squamous cell carcinoma, the PFS of patients with increased CTCs and CTCs ≥2/3.2 ml after treatment was significantly lower (P<0.05). For hypopharyngeal squamous cell carcinoma, it was suggested that CTCs with a cutoff value of 3 may be used to evaluate PFS and OS before and after treatment. In conclusion, CTCs may be used to monitor disease progression and the response to chemoradiotherapy for patients with LA‑HNSCC. Furthermore, CTCs are a better predictor of the prognosis of hypopharyngeal squamous cell carcinoma than that of nasopharyngeal squamous cell carcinoma.