Detection of circulating tumor cells using oHSV1-hTERT-GFP in lung cancer

Evaluation of Liquid Biopsy in Patients with HER2-Positive Breast Cancer

Breast cancer is one of the common malignant tumors, and liquid biopsy has become a hot spot for clinical testing. To clarify the detection effect of liquid biopsy in breast cancer, we collected peripheral blood of HER2-positive (human epidermal growth factor receptor 2-positive) patients. Circulating tumor cells (CTCs) were isolated and analyzed. HER2 expression on CTCs was detected. The results showed that in the 198 HER2-positive samples, the CTC detection rate was 79.8% (158/198), and the mean number of CTCs was 21, ranging from 1 to 63/7.5 mL peripheral blood. Only 41.1% (65/158) of patients had histology and CTC HER2 status consistent with the remaining 58.9% (93/158) of patients, although their histological HER2 was positive, and CTC HER2 was negative. Our study confirmed the value of CTC HER2 real-time status testing in HER2-positive breast cancer patients. The inconsistency in HER2 status between CTCs and histology may be related to the time interval between CTCs and histological HER2 detection, suggesting that real-time HER2 detection is necessary for histological HER2-positive patients.

Prospective Exploratory Study of the Clinical Significance of Circulating Tumor Cells in Patients With Small Cell Lung Cancer Exposed to Prophylactic Cranial Irradiation

OBJECTIVE

Circulating tumor cells (CTCs) can predict the efficacy of anti-cancer treatments and indicate prognosis. Here we investigate the significance of CTCs in relation to the prediction of treatment efficacy and prognosis in patients with small cell lung cancer (SCLC) who have received prophylactic cranial irradiation (PCI).

METHODS

CTCs were detected in 20 patients with SCLC before and after PCI using the oHSV1-hTERT-GFP method. The primary endpoints were progression-free survival (PFS) and overall survival (OS).

RESULTS

Eleven patients had limited-stage SCLC, and nine had extensive-stage SCLC. All patients completed chemo-radiotherapy and received PCI. The median baseline CTC count before PCI was 12. After PCI, the median CTC count was 4. The median follow-up time for all enrolled patients was 39.2 months. The median PFS and OS were significantly reduced in patients with ≥4 CTCs after PCI compared to those with <4 CTCs (PFS, 28.1 months vs. not reached, p = 0.001; OS, not reached vs. not reached, p = 0.029). Seven of the 10 patients with ≥4 CTCs after PCI failed after treatment, whereas the10 patients with <4 CTCs after PCI remained alive without tumors. The median PFS and OS were significantly improved in patients who exhibited a rate of CTC decline of ≥58% after PCI compared with patients who exhibited a decline rate of <58% (PFS, 26.4 months vs. not reached, p = 0.006; OS, not reached vs. not reached, p = 0.029).

CONCLUSION

In SCLC patients who receive PCI, the CTC count and rate of CTC decline after PCI significantly correlate with prognosis.

Prognostic and therapeutic significance of circulating tumor cells in patients with lung cancer

BACKGROUND

Lung cancer is the second most common cancer and the main cause of cancer-related mortality worldwide. In spite of various efforts that have been made to facilitate the early diagnosis of lung cancer, most patients are diagnosed when the disease is already in stage IV, which is generally associated with the occurrence of distant metastases and a poor survival. Moreover, a large proportion of these patients will relapse after treatment, heralding the need for the stratification of lung cancer patients in addition to identifying those who are at a higher risk of relapse and, thus, require alternative and/or additional therapies. Recently, circulating tumor cells (CTCs) have been considered as valuable markers for the early diagnosis, prognosis and risk stratification of cancer patients, and they have been found to be able to predict the survival of patients with various types of cancer, including lung cancer. Additionally, the characterization of CTCs has recently provided fascinating insights into the heterogeneity of tumors, which may be instrumental for the development of novel targeted therapies.

CONCLUSIONS

Here we review our current understanding of the significance of CTCs in lung cancer metastasis. We also discuss prominent studies reporting the utility of enumeration and characterization of CTCs in lung cancer patients as prognostic and pharmacodynamic biomarkers for those who are at a higher risk of metastasis and drug resistance.

Circulating tumor cells in the pulmonary vein increase significantly after lobectomy: A prospective observational study

Background

It has been reported that there are more circulating tumor cells (CTCs) in the pulmonary vein (PV) than in the peripheral blood; however, it is unclear whether the CTC count changes in the PV after resection of a lung lobe.

Methods

Thirty‐three lung cancer patients were recruited for the study, including 17 who underwent lobectomy via video‐assisted thoracoscopic surgery and 16 via open thoracotomy. Sixty‐six blood specimens were sampled from the PV before the PV was interrupted and after lobectomy. The CTCs were quantified using the oHSV1‐hTERT‐GFP method.

Results

Before PV interruption, the CTC (pre‐CTC) detection rate was 79.0% (26/33), the mean number of CTCs was 3.36 (median 2, range: 0–18), and there was no significant relationship between the pre‐CTC count and clinical factors, such as histologic findings and pathological T stage (P > 0.05). After lobectomy, the CTC (post‐CTC) detection rate was 100% (33/33), the average number of CTCs was 14.88 (median 11, range: 1–69), and the post‐CTC count was significantly higher in patients in whom the PV was interrupted prior to the pulmonary artery (PA) than in patients in whom the PA was interrupted before the PV (P = 0.016). Overall, the CTC count was significantly higher following surgery (P < 0.001).

Conclusion

Post‐CTC counts were significantly higher than pre‐CTC counts, suggesting that surgical manipulation may potentially dislodge tumor cells into the PV. Interrupting the PV prior to the PA during lobectomy may prevent partial CTC entry into the circulation.

[Progress of Liquid Biopsy in Early Diagnosis of Lung Cancer]

肺癌的早期诊断有利于提高患者的生存率。应用影像学方法对肺癌高风险人群进行筛查，可以起到早发现、早诊断的作用。越来越多的研究显示，液体活检（liquid biopsy）可以对该方法进行替代和补充。检测肺癌患者外周血中的循环肿瘤细胞（circulating tumor cells, CTCs）、循环肿瘤DNA（circulating tumor DNA, ctDNA）、微小核糖核酸（microRNA, miRNA）、外泌体（exosomes）、肿瘤血小板（tumor educated platelets, TEPs）可以用于肺癌的早期诊断，并且可能为影像学检查阴性的高风险人群提供相应的诊疗建议。全文就以上标志物的检测手段、在肺癌早期诊断中的价值以及存在优势与局限性进行综述，以期促进液体活检在肺癌早期诊断、与其他筛查手段相结合方面的应用。