【Abstract】ObjectiveTo construct the eukaryotic expressing plasmid of tumor necrosis factor-related apoptosisinducing ligand（TRAIL），and study its inhibitory effect on hepatic tumor which implanted subcutaneously in nude BALB/c mice.MethodsTotal RNA of U937 cell was extracted, and its extracellular domain (114-281aa) was amplified by RTPCR, then signal peptide was ligated. The recombinant secreting plasmid for TRAIL was constructed successfully which was confirmed by enzyme cleavage identification and sequencing identification. Liver cancer cell (strain No.7402) was implanted subcutaneously in 32 nude BALB/c mice. These mice were randomly divided into two groups: study group and control group. The mice in study group received muscular injection of plasmids for transfection, and the mice in control group received the injection of normal saline at the same time. The size of implanted tumors were measured continuously till the day of sacrificing, tumor cell apoptosis effect was examined by TUNEL method. ResultsIn study group，tumor volume was smaller than that in control group and the bluepurple apoptosis cells were observed under microscope. ConclusionTRAIL plasmid can induce apoptosis of liver cancer cell and can inhibit the growth of liver tumor.
ObjectiveTo explore feasibility and security of conversion chemotherapy of stage Ⅳ gastric cancer.MethodThe research progresses of conversion chemotherapy of stage Ⅳ gastric cancer were summarized by reading relevant literatures.ResultsThe prognosis of stage Ⅳ gastric cancer was poor, its correct treatment strategy was still controversial. At present, the palliative chemotherapy and targeted therapy were mainly used for it. In recent years, the development of chemotherapeutic drugs had improved the survival of some patients who showed the excellent chemotherapy response rate and subsequently undergone surgery, which promoted the derivation of the concept of conversion therapy. For the patients with initial unresectable stage Ⅳ gastric cancer, these patients could get better pathological reaction and then perform R0 operation through the comprehensive measures such as the preoperative chemotherapy, so that the patients could acquire relatively longer survival time. The previous studies indicated that the single unresectable factor, chemotherapy response rate, and whether R0 resection were the important predictors of prognosis for patients with stage Ⅳ gastric cancer.ConclusionsConversion therapy is still at initial stage. Different conversion chemotherapy regime has different response rate. Moreover, expert consensus on case selection, chemotherapy regimen are absent due to lack of high-quality, multi-center, large-sample data. So higher levels of clinical randomized controlled trials are needed to support and guide this practice. In a word, conversion therapy of stage Ⅳ gastric cancer requires multi-disciplinary efforts to carry out an optimal classification to select out suitable candidates, which may provide efficient guidance for comprehensive treatment for stage Ⅳ gastric cancer.