BACKGROUND:Gastric cancer stem cels involved in the neoadjuvant chemotherapy and conventional treatment are closely associated with relapse of gastric cancer. However, this conclusion has not yet been confirmed.
OBJECTIVE:To investigate the effects of gastric cancer stem cels in tumor invasion and metastasis and its effect on angiogenesis ability.
METHODS:We prepared nude mouse models of gastric cancer to isolate and culture gastric cancer stem cels. Harvested gastric cancer stem cels were detected in cel scratch test, ring test, inhibition rate test, cel migration test and tumorigenicity test.
RESULTS AND CONCLUSION:After 7 days of culture, the cels exhibited adherent growth but a lack of regularity that most cels were in a tadpole shape. In the cel scratch test, the scratch width was significantly different at 0 and 24 hours (P < 0.05). Under an inverted microscope, the cels were found to form a ring in the ring test. The 50% inhibiting concentration of gastric cancer stem cels induced by oxaliplatin was significantly lower than that induced by 5-fluorouracil (P < 0.05). The number of cels passing through the basilar membrane was significantly increased after cel migration (P < 0.05). After implantation of gastric cancer stem cels, the gastric tissue quality was significantly higher than that in normal nude mice of gastric cancer (P < 0.05). These findings indicate that gastric cancer stem cels responsible for tumor invasion and migration have stronger angiogenesis ability.

Clinical research coordinator (CRC) can improve the efficiency of clinical research, ensure the accuracy and reliability of the research process, as well as the standardized implementation of research projects and the safety of subjects. However, the CRCs dispatched by the site management organization have problems such as high liquidity, uneven quality, low work initiative, and high management costs. Since 2004, a research hospital in South China had started to employ CRCs by itself, exploring and forming three self-employed CRC management modes: hospital employ-hospital manage, researcher employ hospital manage, and researcher employ-third-party labor dispatch agency manage. The CRCs under hospital employ-hospital manage mode were recruited and selected by the hospital. The hospital established a labor relationship with CRC, and the hospital′s personnel department was responsible for salary distribution and promotion management of professional titles/positions. The relevant labor costs were borne by the hospital′s funds, and the salary standards were also formulated by the hospital. This type of CRC could participate in the promotion of health technology series titles. The CRCs under researcher employ-hospital manage mode were recruited and selected by the researcher. The hospital established a labor relationship with them. The relevant labor costs were borne by the research funding, and the researchers determined the specific salary standards for CRCs based on the salary guidance plan formulated by the hospital. These kind of CRCs could not be promoted to professional titles in hospitals. The CRCs under researcher employ-third-party labor dispatch agency manage mode were recruited and selected by researchers. The third-party labor dispatch agency established an employment relationship with them and provided personnel services. The relevant labor costs were borne by the research funding, and the researchers formulated their own salary standards. Such CRCs could not be promoted to professional titles in hospitals. As of July 2023, the number of self-employed CRCs in the hospital had reached 185, with 75.8% having a bachelor′s degree or above and an average work experience of 4.58 years. Among them, there were 26 people in the hospital hiring-hospital management mode, 45 people in the researcher hiring-hospital management mode, and 114 people in the researcher hiring-third-party labor dispatch agency management mode. These measures had fully released management efficiency, effectively met manpower needs, promoted rapid growth in the number of clinical research projects, and reduced management costs through third-party labor dispatch mode, which could provide references for CRC management in clinical trial institutions of China.