Exosomal lncRNA KLF3-AS1 derived from bone marrow mesenchymal stem cells stimulates angiogenesis to promote diabetic cutaneous wound healing.

AIMS: We focused on BMSC-derived exosomal lncRNA KLF3-AS1 and its significance in diabetic cutaneous wound healing. METHODS: Potential interaction between KLF3-AS1 and miR-383, miR-383 and VEGFA were predicted using bioinformatic analysis and validated by luciferase reporter, RIP, and FISH assays. The proliferation, apoptosis, migration and tube formation of HUVECs were evaluated by CCK-8, flow cytometry, wound healing, and tube formation assays, respectively. A murine diabetic cutaneous wound model was used to investigate therapeutic effects of exosomal KLF3-AS1 in vivo. Histological alterations in skin tissues were examined using HE, Masson staining, and immunostaining of CD31. RESULTS: BMSC-derived exosomal KLF3-AS1 sufficiently promoted proliferation, migration, and tube formation, while inhibited apoptosis of HUVECs challenged by high glucose. The protective effects of exosomal KLF3-AS1 were achieved at least partially by down-regulating miR-383, and boosting the expression of its target, VEGFA. In vivo, exosomes from KLF3-AS1-expressing BMSCs demonstrated the best effects in promoting cutaneous wound healing in diabetic mice, which were associated with minimal weight loss, increased blood vessel formation, reduced inflammation, decreased miR-383 expression, and up-regulated VEGFA. CONCLUSIONS: Exosomal lncRNA KLF3-AS1 derived from BMSCs induces angiogenesis to promote diabetic cutaneous wound healing.

[Inverse correlation of S100A4 and E-cad protein expression and their clinical significance in non-small cell lung cancer].

OBJECTIVE: The purpose of the present study was to explore the relationship between the expression of S100A4 and E-cad protein and some clinicopathological factors such as histological types, TNM stages, lymph node metastasis and prognosis in non-small cell lung cancer (NSCLC), and analyze whether there is a correlation between them. METHODS: The expression of S100A4 protein and E-cad protein was detected with immunohistochemical SP technique in 116 non-small-cell lung cancers. RESULTS: The positive immunohistochemical staining for S100A4 protein was observed in 64 out of the 116 patients, with a positive rate of 55.2%. The expression rate of S100A4 protein was associated with age, tumor size, lymph node metastasis and prognosis of NSCLC. The expression of S100A4 protein was not significantly related with histological types, sex and TNM stages. The positive rate of E-cad protein expression was 65.5%. The expression of E-cad protein was associated with TNM staging, lymph node metastasis and prognosis of NSCLC. The expression of E-cad protein had no significant correlation with histological types, patient age and sex. An inverse correlation between the levels of S100A4 and E-cad protein expression was found (P < 0.005). CONCLUSION: Expression of S100A4 protein and loss of E-cad protein expression are significantly associated with tumor progression, and may become valuable markers in prediction of biological behavior and tendency of metastasis of non-small-cell lung cancers.

Knocking Down Nucleolin Expression Enhances the Radiosensitivity of Non-Small Cell Lung Cancer by Influencing DNA-PKcs Activity.

Nucleolin (C23) is an important anti-apoptotic protein that is ubiquitously expressed in exponentially growing eukaryotic cells. In order to understand the impact of C23 in radiation therapy, we attempted to investigate the relationship of C23 expression with the radiosensitivity of human non-small cell lung cancer (NSCLC) cells. We investigated the role of C23 in activating the catalytic subunit of DNA-dependent protein kinase (DNA- PKcs), which is a critical protein for DNA double-strand breaks (DSBs) repair. As a result, we found that the expression of C23 was negatively correlated with the radiosensitivity of NSCLC cell lines. In vitro clonogenic survival assays revealed that C23 knockdown increased the radiosensitivity of a human lung adenocarcinoma cell line, potentially through the promotion of radiation-induced apoptosis and adjusting the cell cycle to a more radiosensitive stage. Immunofluorescence data revealed an increasing quantity of γ-H2AX foci and decreasing radiation-induced DNA damage repair following knockdown of C23. To further clarify the mechanism of C23 in DNA DSBs repair, we detected the expression of DNA-PKcs and C23 proteins in NSCLC cell lines. C23 might participate in DNA DSBs repair for the reason that the expression of DNA-PKcs decreased at 30, 60, 120 and 360 minutes after irradiation in C23 knockdown cells. Especially, the activity of DNA-PKcs phosphorylation sites at the S2056 and T2609 was significantly suppressed. Therefore we concluded that C23 knockdown can inhibit DNA-PKcs phosphorylation activity at the S2056 and T2609 sites, thus reducing the radiation damage repair and increasing the radiosensitivity of NSCLC cells. Taken together, the inhibition of C23 expression was shown to increase the radiosensitivity of NSCLC cells, as implied by the relevance to the notably decreased DNA-PKcs phosphorylation activity at the S2056 and T2609 clusters. Further research on targeted C23 treatment may promote effectiveness of radiotherapy and provide new targets for NSCLC patients.