Extending the time window of mammalian heart regeneration by thymosin beta 4.

Recent studies demonstrated that the heart of 1-day-old neonatal mice could regenerate, with Wt1(+) EPDCs migrating into myocardial regions after partial surgical resection, but this capacity was lost by 7 days of age. By treatment with Tß4 to maintain Wt1 expression and retain the migrating feature of EPDCs in neonatal mice, we explored the possibility of restoring the cardiac regeneration potential of mice. We intraperitoneally injected Tß4 into 1-day-old mice on daily basis and then apical resection was performed on the mice 7 days later. Twenty one days after the resection, morphological analysis revealed that the Tß4-treated mice regenerated the resected ventricular apex, while the mice in PBS control group developed significant fibrosis without apical regeneration. The Tß4-treated mice had significantly better ventricular ejection fraction and fractional shortening than controls. During the process of regeneration, Wt1(+) EPDCs migrated into myocardial region and some of them expressed Islet1 and the markers for mature cardiomyocytes, such as cTnT and SαA. These characteristics of Wt1(+) EPDCs were also seen in the heart regeneration of mice subjected to apical resection 1 day after birth. Tß4 has no essential effect on cell cycle activity as no disruption of actin filaments was observed in Tß4-treated hearts. These results revealed that the cardiac regeneration potential of neonatal mice could be extended to the 7th post-natal day by Tß4 and Wt1(+) EPDCs mobilization might play an important role in the extension.

Application status of commonly used patches in breast reconstruction / 中国肿瘤临床

Breast reconstruction is an essential part in the comprehensive management of breast cancer. The clinical application of patches (e.g., acellular dermal matrix, ADM) is the most impactful innovation in implant breast reconstruction in recent years. The wide application of patches in implant breast reconstruction promotes the development of immediate prosthetic reconstruction, im-proves the aesthetic outcomes of reconstructed breasts, and avoids additional donor tissue damage caused by autologous flap breast reconstruction. At present, patches used in breast reconstruction are mainly ADMs, bovine pericardial patches, and TiLOOP, which are widely used because of their good histocompatibility and tissue defect repair ability. This article reviews the applications and research statuses of these patches.

Effect of cancer-associated fibroblasts-derived CCL7 on proliferation and invasion of triple-negative breast cancer cells / 国际生物医学工程杂志

Objective To investigate the effect of cancer-associated fibroblasts (CAFs)-derived chemokine ligands 7 (CCL7) on the proliferation and invasion of triple-negative breast cancer (TNBC) cells. Methods The mRNA expression level and protein level of CCL7 in CAFs and paracancerous fibroblasts were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western Blot respectively. To confirm the paracrine level of CCL7 in CAFs and paracancerous fibroblasts, the protein levels of CCL7 in the corresponding conditional medium were detected through enzyme-linked immunosorbent assay (ELISA). The effect of CCL7 on the proliferation and invasion of MDA-MB-231 (TNBC cell line) was investigated by MTS assay and Transwell assay, respectively. Results In comparison with paracancerous fibroblasts, the mRNA expression level and protein level of CCL7 in CAFs were significantly increased (both P<0.01). There was an obviously increase of paracrine level of CCL7 in CAFs-conditional medium (P<0.01). The MTS assay and Transwell assay results indicated that CCL7 was more able to promote the proliferation and invasion of MDA-MB-231. Conclusion CAFs in the TNBC stroma can produce more chemokine CCL7, and CCL7 can promote the proliferation and invasion of TNBC cells

Construction of EZH2 gene site-directed knock-in Hut78 cells by CRISPR/Cas9 system / 天津医药

Objective To construct the Hut78 cell line with EZH2 gene knocked into by CRISPR/Cas9 system. Methods The EZH2 expression vector pMD-18T-EZH2 with homologous arm and the sgRNA expression vector pSpCas9 (BB)-2A-Puro-sgRNA, which could cut the double stranded genomic DNA, were constructed, and the two vectors were co-transfected into Hut78 cells. Then the expression of EZH2 mRNA was detected by qPCR, and the expressions of EZH2 and H3K27me3 proteins were detected by Western blot assay. Results The pMD-18T-EZH2 and pSpCas9(BB)-2A-Puro-sgRNA recombinant vectors were confirmed by DNA sequencing. When Hut78 cells were transfected with the two recombinant plasmid, qPCR results showed that the expression of EZH2 mRNA was significantly increased, and Western blot analysis showed that the expressions of EZH2 and H3K27me3 proteins were significantly increased. Conclusion EZH2 gene is successfully knocked into Hut78 cells by CRISPR/Cas9 system.