microRNA (miRNA, miR) has attracted great interest in recent years. miR-138 is closely related to the occurrence, development and prognosis of different kinds of malignant tumors.Present studies have shown that miR-138 is frequently down-regulated in tumor cells and tissues. Down-regulation expression of miR-138 can promote the proliferation, invasion and metastasis in a variety of malignant tumor cells. Up-regulation expression of miR-138 may play a crucial role in tumor suppression, and enhance sensitivity of tumor cells to radiotherapy and chemotherapy. Therefore, miR-138 can be considered as a biomarker of tumor prognosis, and also one of the tumor therapeutic targets.

ObjectiveTo understand the concentration levels of benzene， toluene and xylene in the workplaces of enterprises involved in benzene and benzene series in Jinshan District， and to provide the basis for the government to formulate key occupational disease prevention and control strategies. MethodsFrom 2016 to 2021， enterprises involved in benzene and benzene series were sampled individually， and the monitoring results of benzene and benzene series were statistically analyzed through workplace air sampling and laboratory detection. ResultsFrom 2016 to 2021， a total of 80 enterprises were monitored， and the total passing rate of individual monitoring was 87.50%， which decreased first and then increased. The difference was not statistically significant. A total of 387 individuals were sampled with a total passing rate of 95.61% and a detection rate of 73.38% （284 individuals）. The detection rates of benzene， toluene and xylene were 6.46%， 29.97% and 36.95%， respectively. The exceedance rates were 1.03%， 0.26% and 3.10%， respectively. Among the companies exceeding the standard， the metal products industry had the highest rate of exceedance （19.05%）. For individuals， those working in the printing and recording media reproduction industry had the highest rate of exceedance （10.26%）. ConclusionThe passing rate and detection rate of benzene and benzene series are relatively high in Jinshan District. The metal products industry and the printing and recording media reproduction industry have a higher exceedance rate of benzene and benzene series.