AIM: To determine the relationship between the mutation of the RII gene and RER status in the tumorigenesis of sporadic colorectal cancer. METHODS: We screened RER status and mutation of the RII gene from 50 sporadic colorectal cancers (19 in the proximal colon, 31 in the distal colorectum). RESULTS: RER was found in 13 cases (8 in the proximal colon, 5 in the distal colorectum), and 5 of them showed mutations of the RII gene. All 5 cancers carrying a TGF-? RII gene mutation showed RER+, but there wasn't any mutation of RII gene in RER(-) cases. Four of 5 RII mutation were located at the cecum. CONCLUSION: These data indicate that the TGF-? RII gene is a major target of microsatellite instability and mutation of the RII gene play an important role in carcinogenesis of sporadic colorectal cancer with microsatellite instability, especially at the cecum. [

Lung cancer is the second most common cancer worldwide, and 40% of patients with non-small cell lung cancer may develop brain metastases. Radiotherapy is a classic treatment for brain metastases, and immunotherapy has emerged for advanced non-small cell lung cancer. This article discusses the theoretical bases, clinical efficacy and safety, and the optimum timing of radiotherapy combined with immunotherapy for brain metastases from non-small cell lung cancer to provide reference for clinical practice and scientific research.

Cell membrane-modified nanoparticles (NPs) have attracted widespread attention as a new approach for malignant brain tumors in recent years. This method can enhance the targeting, biocompatibility, and circulation time of NPs by preserving the characteristics of source cell membrane, thereby ensuring efficient drug delivery to intracranial lesions. This paper focuses on the research progress in this field, especially advantages of NPs penetrating the blood-brain barrier, immune evasion and drug delivery, as well as modified effect of different cell membrane on NPs, in order to provide help for treatment of malignant brain tumors.

Objective:To prepare PLGA electrospinning membranes doped with hollow mesoporous silica nanoparticles loaded with metformin and investigate their biological properties.Methods:PLGA(Control group)and PLGA/HMSN/Met electrospun membranes(Experimental group)were prepared by electrospinning technology.The microscopic morphology of the 2 groups of electrospun mem-branes was observed by SEM.The hydrophilicity,elemental composition and in vitro drug release were detected by contact angle meas-urement,EDS,and drug release test,respectively.SEM and laser scanning confocal microscope(LSCM)were used to observe the growth of periodontal ligament stem cells(PDLSCs)on the 2 groups of electrospun membranes,and CCK-8 assay was used to detect the cell proliferation.Results:Both electrospun membranes had extracellular matrix(ECM)-like fiber structures.The PLGA/HMSN/Met electrospun membranes could slowly release Met for up to 35 days,and the hydrophilicity of PLGA membranes was improved by HMSN-Met doped.The composite electrospun membranes had good cell biocompatibility in vitro,and could promote cell proliferation.Conclu-sion:Modification of PLGA with HMSN-Met can improve the hydrophilicity of PLGA electrospun membranes,continuously release Met,and have good cell biocompatibility.