The expression of X-linked inhibitor of apoptosis protein (XIAP) gene and its effect on chemotherapeutic sensitivity in bladder carcinoma was explored. By using immunohistochemistry, the expression of XIAP was detecte...The expression of X-linked inhibitor of apoptosis protein (XIAP) gene and its effect on chemotherapeutic sensitivity in bladder carcinoma was explored. By using immunohistochemistry, the expression of XIAP was detected in 47 bladder carcinomas and 5 normal bladder tissues. The XIAP gene was transfected into bladder cancer cell line T24 by liposome and the positive clone was screened by G418. Cellular XIAP mRNA level was detected by RT-PCR. Low-dose mitocycin C was administered to induce the apoptosis of T24 cells. The in vitro growth of bladder carcinoma cells was analyzed by MTT colorimetry, and the apoptosis rate was assayed by TUNEL methods. It was found XIAP was moderately expressed in bladder carcinomas with the the positive rate being 78.73% (37/47), but the positive rate was not correlated with carcinoma stages and grades (P<0.05). XIAP mRNA level in transfected T24 cells was significantly increased by 3.8 times as compared with that in the cells not transfected with XIAP. After treatment with low-dose mitomycin C (0.005 and 0.05 mg/mL), the growth rate in XIAP no-transfected control group was increased by (11.60±0.25)% and (16.51±0.87)% (P<0.05), and the apoptosis rate was decreased by (10.1±0.2)% and (11.9±0.2%) (P<0.05) respectively as compared with XIAP transfected group. It was concluded that XIAP was expressed in most of bladder carcimoma samples. Overexpression of XIAP in T24 could significantly reduce the MMC-induced apoptosis of bladder carcinoma, suggesting its effect on the chemothera- peutic sensitivity of T24 cells.展开更多
目的:探讨高迁移率族蛋白B1(high mobility group box-1,HMGB1)对宫颈癌细胞化学治疗敏感性的影响及其机制。方法:采用Western印迹法检测宫颈癌细胞HeLa和CaSki经不同药物浓度顺铂处理后LC3,Beclin1及P62的表达水平,检测使用自噬抑制剂...目的:探讨高迁移率族蛋白B1(high mobility group box-1,HMGB1)对宫颈癌细胞化学治疗敏感性的影响及其机制。方法:采用Western印迹法检测宫颈癌细胞HeLa和CaSki经不同药物浓度顺铂处理后LC3,Beclin1及P62的表达水平,检测使用自噬抑制剂和/或顺铂处理后宫颈癌细胞HeLa和CaSki中LC3,Beclin1及P62的表达水平;采用细胞计数试剂盒8(cell counting kit-8,CCK-8)检测细胞增殖水平。构建HeLa-sh HMGB1,CaSkish HMGB1,HeLa-CTR及CaSki-CTR的稳定细胞系。以CCK-8检测上述细胞系顺铂半数抑制浓度(half maximum inhibitory concentration,IC50)水平;Western印迹法检测上述细胞系中HMGB1,LC3,Beclin1及P62的表达水平。结果:在一定浓度范围内,随着顺铂药物浓度的增加,宫颈癌细胞HeLa和CaSki中LC3及Beclin1的表达增加,P62表达降低。与单用顺铂组相比,顺铂联合自噬抑制剂组细胞存活率更低(P<0.05)。在宫颈癌细胞中,HMGB1的表达与顺铂药物敏感性有关(P<0.05),与LC3,Beclin1表达呈正相关,与P62表达呈负相关。结论:HMGB1可能通过调控宫颈癌细胞内自噬的水平,影响其对顺铂的敏感性。铂类药物结合自噬抑制剂可能成为宫颈癌治疗的新策略。HMGB1可能成为预测化学治疗药物敏感性的分子标志物。展开更多
DNA damage response(DDR)is a highly conserved genome surveillance mechanism that preserves cell viability in the presence of chemotherapeutic drugs.Hence,small molecules that inhibit DDR are expected to enhance the an...DNA damage response(DDR)is a highly conserved genome surveillance mechanism that preserves cell viability in the presence of chemotherapeutic drugs.Hence,small molecules that inhibit DDR are expected to enhance the anti-cancer effect of chemotherapy.Through a recent chemical library screen,we identified shikonin as an inhibitor that strongly suppressed DDR activated by various chemotherapeutic drugs in cancer cell lines derived from different origins.Mechanistically,shikonin inhibited the activation of ataxia telangiectasia mutated(ATM),and to a lesser degree ATM and RAD3-related(ATR),two master upstream regulators of the DDR signal,through inducing degradation of ATM and ATR-interacting protein(ATRIP),an obligate associating protein of ATR,respectively.As a result of DDR inhibition,shikonin enhanced the anti-cancer effect of chemotherapeutic drugs in both cell cultures and in mouse models.While degradation of ATRIP is proteasome dependent,that of ATM depends on caspase-and lysosome-,but not proteasome.Overexpression of ATM significantly mitigated DDR inhibition and cell death induced by shikonin and chemotherapeutic drugs.These novel findings reveal shikonin as a pan DDR inhibitor and identify ATM as a primary factor in determining the chemo sensitizing effect of shikonin.Our data may facilitate the development of shikonin and its derivatives as potential chemotherapy sensitizers through inducing ATM degradation.展开更多
Late-stage modification of peptides and proteins meets the increasing demand in biochemical and pharmaceutical communities. These modification strategies could provide functionalized nonproteinogenic analogues with en...Late-stage modification of peptides and proteins meets the increasing demand in biochemical and pharmaceutical communities. These modification strategies could provide functionalized nonproteinogenic analogues with enhanced biological activities or improved therapeutic capabilities compared to their natural counterparts. Recent years, transition-metal-promoted functionalization of ubiquitous C-H bonds has been emerged as a powerful and tunable tool in this area, both for backbone diversifications and labeling of specific moieties. These reactions were flexible and expedient in both academic and industrial laboratories, especially considering their atom and step-economy, good functional group compatibility, accurate site selectivity. This review surveys the progress achieved in the late-stage modification of peptides and proteins utilizing transition-metal-catalyzed C-H functionalization with C-C and C-X(F, Cl, O, N, B, etc.) bonds formation.展开更多
基金a grant from National Natu-ral Sciences Foundation of China (No. 30271301)
文摘The expression of X-linked inhibitor of apoptosis protein (XIAP) gene and its effect on chemotherapeutic sensitivity in bladder carcinoma was explored. By using immunohistochemistry, the expression of XIAP was detected in 47 bladder carcinomas and 5 normal bladder tissues. The XIAP gene was transfected into bladder cancer cell line T24 by liposome and the positive clone was screened by G418. Cellular XIAP mRNA level was detected by RT-PCR. Low-dose mitocycin C was administered to induce the apoptosis of T24 cells. The in vitro growth of bladder carcinoma cells was analyzed by MTT colorimetry, and the apoptosis rate was assayed by TUNEL methods. It was found XIAP was moderately expressed in bladder carcinomas with the the positive rate being 78.73% (37/47), but the positive rate was not correlated with carcinoma stages and grades (P<0.05). XIAP mRNA level in transfected T24 cells was significantly increased by 3.8 times as compared with that in the cells not transfected with XIAP. After treatment with low-dose mitomycin C (0.005 and 0.05 mg/mL), the growth rate in XIAP no-transfected control group was increased by (11.60±0.25)% and (16.51±0.87)% (P<0.05), and the apoptosis rate was decreased by (10.1±0.2)% and (11.9±0.2%) (P<0.05) respectively as compared with XIAP transfected group. It was concluded that XIAP was expressed in most of bladder carcimoma samples. Overexpression of XIAP in T24 could significantly reduce the MMC-induced apoptosis of bladder carcinoma, suggesting its effect on the chemothera- peutic sensitivity of T24 cells.
基金supported by Guangdong Basic and Applied Basic Research Foundation(2021A1515011244,China)to Jinshan Tangthe National 111 Project of China(No.B13038,China)to Xinsheng Yao。
文摘DNA damage response(DDR)is a highly conserved genome surveillance mechanism that preserves cell viability in the presence of chemotherapeutic drugs.Hence,small molecules that inhibit DDR are expected to enhance the anti-cancer effect of chemotherapy.Through a recent chemical library screen,we identified shikonin as an inhibitor that strongly suppressed DDR activated by various chemotherapeutic drugs in cancer cell lines derived from different origins.Mechanistically,shikonin inhibited the activation of ataxia telangiectasia mutated(ATM),and to a lesser degree ATM and RAD3-related(ATR),two master upstream regulators of the DDR signal,through inducing degradation of ATM and ATR-interacting protein(ATRIP),an obligate associating protein of ATR,respectively.As a result of DDR inhibition,shikonin enhanced the anti-cancer effect of chemotherapeutic drugs in both cell cultures and in mouse models.While degradation of ATRIP is proteasome dependent,that of ATM depends on caspase-and lysosome-,but not proteasome.Overexpression of ATM significantly mitigated DDR inhibition and cell death induced by shikonin and chemotherapeutic drugs.These novel findings reveal shikonin as a pan DDR inhibitor and identify ATM as a primary factor in determining the chemo sensitizing effect of shikonin.Our data may facilitate the development of shikonin and its derivatives as potential chemotherapy sensitizers through inducing ATM degradation.
基金the support from the National Key R&D Program of China(No. 2017YFA0505400)the National Natural Science Foundation of China (Nos. 21572214, 21702200)
文摘Late-stage modification of peptides and proteins meets the increasing demand in biochemical and pharmaceutical communities. These modification strategies could provide functionalized nonproteinogenic analogues with enhanced biological activities or improved therapeutic capabilities compared to their natural counterparts. Recent years, transition-metal-promoted functionalization of ubiquitous C-H bonds has been emerged as a powerful and tunable tool in this area, both for backbone diversifications and labeling of specific moieties. These reactions were flexible and expedient in both academic and industrial laboratories, especially considering their atom and step-economy, good functional group compatibility, accurate site selectivity. This review surveys the progress achieved in the late-stage modification of peptides and proteins utilizing transition-metal-catalyzed C-H functionalization with C-C and C-X(F, Cl, O, N, B, etc.) bonds formation.
