| Small cell lung cancer, accounting for about 15% of clinical lung cancer cases, is an aggressive malignancy with a distinct natural history and dismal prognosis. It displays a distinct natural history characterized by a high growth fraction, rapid doubling time and early establishment of widespread metastatic lesions. While about 30% of patients present with disease confined to one hemithorax, the majority of cases have disease not encompassed by one radiotherapy field.The circulating tumor cells have important value in early diagnosis, individualized treatment, the evaluation of therapeutic effect and mechanism of tumor metastasis. Telomerase activity is inhibited in normal human tissue cells, which is activated in tumor cells, so it can be used to trace circulating tumor cells. The study is to establish a method to detect circulating tumor cells in the peripheral blood of small cell lung cancer patients based on herpes simplex virus inserted with human telomerase promoter and green fluorescent protein gene.In this study, we infected different tumor cell lines with oHSV1-hTERT-GFP to observe the expression of GFP, and the captured cancer cells were validated by the expression of CD56. Models in vitro of circulating tumor cells were established. The results showed that in the model of NCI-H69, the check out rate was 87.7%. In NCI-H446, the check out rate was 89.8%. It showed that the efficiency of oHSVl-hTERT-GFP virus in capturing circulating tumor cells was not related to the content of small cell lung cancer cells in peripheral blood.We observed the relationship between the number of circulating tumor cells and the clinical effect by the clinical cases. We collected 100 cases of healthy human peripheral blood,4ml each case, the oHSV1-hTERT-GFP method was used to detect CD45-/GFP+ cells. The true negative rate was 98% (the number of cells detected was no more than 3/4ml). We collected peripheral blood samples from 40 cases of primary small cell lung cancer patients, including 28 patients with extensive stage small cell lung cancer, 12 cases of limited stage small cell lung cancer. These patients all accepted chemotherapy and thoracic radiotherapy, and among these patients,23 cases accepted the radiotherapy of brain prevention. We collected 4ml of peripheral blood from each patient every time. The circulating tumor cells were marked by oHSV1-hTERT-GFP and counted by flow cytometry. The mean number of CD45-/GFP+ cells in peripheral blood from small cell lung cancer patients before therapy was significantly higher than that of healthy people. Among the patients, the mean number of CD45-/GFP+ cells was 39.64± 6.23 in the cases of the extensive stage. While in the limited stage, the average number was 8.92±7.33. The detection rate of CD45-/GFP+in 40 patients with small cell lung cancer was 92.5%, and in the cases of extensive stage was 100%, in the limited stage was 75%. Paired comparison analysis showed that the average number of CD45-/GFP+cells in the cases before treatment was 30.42±15.66. It was significantly higher than that after radiotherapy and chemotherapy. The number of CD45-/GFP+ cells changed from 6 to 17 in one of the patients with disease progression. The number of CD45-/GFP+ cells detected was consistent with the clinical condition. These results show that the method has good sensitivity and specificity.In summary, this study established a new method to detect circulating tumor cells in small cell lung cancer. This method can be used to trace the circulating tumor cells of small cell lung cancer, and it has potential clinical application value.In the first part, we have established a new platform using oHSV1-hTERT-GFP method to detect the circulating tumor cells of small cell lung cancer. Finally, we conclude that this method does not depend on the surface markers of tumor cells, and is not restricted by the shape and size of the tumor cells.In this part, we will use this technique to detect the circulating tumor cells in the peripheral blood of NK/T cell lymphoma. The reliability and clinical application value were discussed. First, we infected different lymphoma cell lines with oHSV1-hTERT-GFP to observe the expression of GFP> and the captured cancer cells were validated by the expression of CD56 in SNK6.At last, we observed the relationship between the number of circulating tumor cells and the clinical effect by the clinical cases. We collected 50 cases of healthy human peripheral blood,4ml each case, the oHSVl-hTERT-GFP method was used to detect GFP+ cells. The true negative rate was 98% (the number of cells detected was no more than 50/105).20 samples from primary NK/T cell lymphoma patients were also collected, the mean number of GFP+ cells was 435.25±488.76/105, which is higher than that of healthy people of 28.78±14.05/105. And as the stage of the lymphoma being higher, the mean number of GFP+ cells was increasing. Paired comparison analysis showed that the average number of GFP+ cells in the cases before treatment.Therefore, this method can be used to trace the circulating tumor cells of NK/T cell lymphoma, and it has potential clinical application value. It has important value in the early diagnosis, individual treatment, curative effect evaluation and mechanism of tumor metastasis in NK/T cell lymphoma. |
