Effects of Corticosterone, cAMP, cGMP, Ca^(2+), and Protein Kinase C on Apoptosis of Mouse Thymocytes Induced by X-ray Irradiation

Objective To observe the effects of signal factors of corticosterone （CS）, cAMP, cGMP, Ca^2＋ and protein kinase C （PKC） on lymphocyte apoptosis in mouse thymus induced by X-rays of 4 Gy in vitro. Methods The DNA lyric rate for thymocytes was measured by fluomspectrophotometry. Results The DNA lyric rate for thymocytes 4-8 hours after irradiation with 2-8 Gy was significantly higher than that in the control （P〈0.01）. As compared with the control, the DNA lyric rate for thymocytes treated with 0.01 μnol/L CS （P〈0.01）, 50 ng/mL cAMP （P〈0.01）, 0.05-0.4 μg/mL ionomycin （Iono, P〈0.05 or P〈0.01） or 0.05-0.4 ng/mL phorbol myristate acetate （PMA, P〈0.05 or P〈0.01）, respectively, was significantly increased, while the rate for thymocytes treated with 50 ng/mL cGMP was not significantly increased. The DNA lyric rate for thymocytes treated with 0.01 μmol/L CS （P〈0.01）, 50 ng/mL cAMP （P〈0.01）, 0.2 and 0.4 μg/mL Iono （P〈0.05）, and 0.2 and 0.4 ng/mL PMA （P〈0.05） plus 4-Gy irradiation, respectively, was significantly higher than that treated with single 4-Gy irradiation, while the rate for thymocytes treated with 50 ng/mL cGMP plus 4-Gy irradiation was not increased. When both 0.4 I.tg/mL Iono and 0.4 ng/mL PMA acted on the thymocytes, the DNA lyric rate for thymocytes was significantly higher than that in the control （P〈0.01）, the DNA lytic rate for thymocytes treated with both 0.4 μg/mL Iono and 0.4 ng/mL PMA plus 4-Gy irradiation was significantly higher than that treated with single 4-Gy irradiation （P〈0.05）, but was Iono plus 4-Gy irradiation or 0.4 ng/mL PMA plus 4-Gy irradiation. can promote thymocyte apoptosis induced by larger dose X-rays. not significantly higher than that treated with 0.4 μg/mL Conclusion CS, cAMP, Ca^2＋, and PKC signal factors can promote thymocyte apoptosis induced by larger dose X-rays.

血清肿瘤标记物在视网膜母细胞瘤诊断中的研究

目的:探讨血清肿瘤标记物神经元特异性烯醇化酶(NSE)、糖蛋白抗原CA153、CA199在视网膜母细胞瘤(RB)患者血清中的分泌水平。方法:选取2017-10/2019-10在深圳市人民医院进行化疗且临床资料完整的RB患儿42例为研究对象,检测首次化疗前空腹静脉血血清中肿瘤标记物NSE、CA153、CA199水平,比较不同性别、不同临床分期、单双眼受累患者血清肿瘤标记物水平的差异。结果:晚期组患儿血清肿瘤标记物NSE、CA153、CA199水平均高于早中期组(49.69±18.45ng/mL vs 36.18±14.92ng/mL,22.38±12.03U/mL vs 15.10±8.32U/mL,46.44±18.76U/mL vs 30.21±24.03U/mL,P<0.05),但不同性别、单双眼受累患儿血清各肿瘤标记物水平均无明显差异(P>0.05)。结论:血清NSE、CA153、CA199在临床晚期RB患者血清中的分泌水平明显高于早中期患者,其对RB分期诊疗可能具有重要意义。

BRAF_(V600E)mutant colorectal cancer cells mediate local immunosuppressive microenvironment through exosomal long noncoding RNAs

BACKGROUND BRAF^(V600E) mutated colorectal cancer(CRC)is prone to peritoneal and distant lymph node metastasis and this correlates with a poor prognosis.The BRAF^(V600E) mutation is closely related to the formation of an immunosuppressive microenvironment.However,the correlation between BRAF^(V600E) mutation and changes in local immune microenvironment of CRC is not clear.AIM To explore the effect and mechanism of BRAF^(V600E) mutant on the immune microenvironment of CRC.METHODS Thirty patients with CRC were included in this study:20 in a control group and 10 in a treatment group.The density of microvessels and microlymphatic vessels,and M2 subtype macrophages in tumor tissues were detected by immunohistochemistry.Screening and functional analysis of exosomal long noncoding RNAs(lncRNAs)were performed by transcriptomics.The proliferation and migration of human umbilical vein endothelial cells(HUVECs)and human lymphatic endothelial cells(HLECs)were detected by CCK-8 assay and scratch test,respectively.The tube-forming ability of endothelial cells was detected by tube formation assay.The macrophage subtypes were obtained by flow cytometry.The expression of vascular endothelial growth factor(VEGF)-A,basic fibroblast growth factor(bFGF),transforming growth factor(TGF)-β1,VEGF-C,claudin-5,occludin,zonula occludens(ZO)-1,fibroblast activation protein,andα-smooth muscle actin was assessed by western blot analysis.The levels of cytokines interleukin(IL)-6,TGF-β1,and VEGF were assessed by enzyme-linked immunosorbent assay.RESULTS BRAF^(V600E) mutation was positively correlated with the increase of preoperative serum carbohydrate antigen 19-9(P<0.05),and with poor tumor tissue differentiation in CRC(P<0.01).Microvascular density and microlymphatic vessel density in BRAF^(V600E) mutant CRC tissues were higher than those in BRAF wildtype CRC(P<0.05).The number of CD163+M2 macrophages in BRAF^(V600E) mutant CRC tumor tissue was markedly increased(P<0.05).Compared with exosomes from CRC cells with BRAF gene silencing,the expression of 13 lncRNAs and 192 mRNAs in the exosomes from BRAF^(V600E) mutant CRC cells was upregulated,and the expression of 22 lncRNAs and 236 mRNAs was downregulated(P<0.05).The biological functions and signaling pathways predicted by differential lncRNA target genes and differential mRNAs were closely related to angiogenesis,tumor cell proliferation,differentiation,metabolism,and changes in the microenvironment.The proliferation,migration,and tube formation ability of HUVECs and HLECs induced by exosomes in the 1627 cell group(HT29 cells with BRAF gene silencing)was greatly reduced compared with the HT29 cell group(P<0.05).Compared with the HT29 cell group,the expression levels of VEGF-A,bFGF,TGF-β1,and VEGF-C in the exosomes derived from 1627 cells were reduced.The expression of ZO-1 in HUVECs,and claudin-5,occludin,and ZO-1 in HLECs of the 1627 cell group was higher.Compared with the 1627 cell group,the exosomes of the HT29 cell group promoted the expression of CD163 in macrophages(P<0.05).IL-6 secretion by macrophages in the HT29 cell group was markedly elevated(P<0.05),whereas TGF-β1 was decreased(P<0.05).The levels of IL-6,TGF-β1,and VEGF secreted by fibroblasts in the 1627 cell group decreased,compared with the HT29 cell group(P<0.05).CONCLUSION BRAF^(V600E) mutant CRC cells can reach the tumor microenvironment by releasing exosomal lncRNAs,and induce the formation of an immunosuppressive microenvironment.