Personalized medicine modality based on patient-derived xenografts from a malignant transformed GCTB harboring H3F3A G34W mutation.

BACKGROUND: The function of H3F3A G43W mutation, which has been observed in almost all GCTB, remains poorly characterized. Breakthrough in malignant GCTB has been trapped by the lack of clinical available drugs, limited canonical patient samples and paucity of fidelity preclinical models. METHODS: Tumor samples obtained from a malignant GCTB was implanted in immunodeficient mice for the generation of PDX. Histological examination and short tandem repeat (STR) were used for inherited features analyses. An epigenetic/transcriptional targeted compound library was selected for drug screening. The in vivo effects of selected drug were validated in PDX model. RESULTS: We established the PDX model with recurrent malignant GCTB specimens, histological examination and STR analyses revealed that PDX and their corresponding parental patients shared the same STRs and histologic features, suggesting common origins. ITF-2357 was the most significant compound with an IC50 lower than 0.1 uM. The results of the drug screening and in vivo PDX validation demonstrated that ITF-2357 might be a promising drug targeted H3F3A G34W mutation MGCTBs. CONCLUSION: Our study demonstrates that PDX model maintained the same histologic and genetic features as those in the original patient. targeting HDAC through ITF-2357 effectively overcomes malignant GCTB progression in vitro and in vivo. TRANSLATIONAL POTENTIAL STATEMENT: As PDX retain the principal histologic and genetic characteristics of the primary tumors, mad it a valuable research tool in predictive clinical efficacy. In this study, we first established a malignant GCTB PDX model, which might further accelerate the progress of drug development in malignant GCTB.

Directed elimination of senescent cells attenuates development of osteoarthritis by inhibition of c-IAP and XIAP.

Aging drives the accumulation of senescent cells (SnCs) by secreting factors that cause the senescence-associated secretory phenotype (SASP), including stem cells in the bone marrow, which contribute to aging-related bone degradation. Osteoarthritis (OA) is a serious chronic injury disease, and increasing age is a major risk factor. The accumulation of SnCs may accelerate the development of OA, and the accumulation of SnCs may benefit from its resistance to apoptotic stimuli. Therefore, local elimination of SnCs could be a promising treatment for OA. Apoptosis inhibitor protein (IAP) is an important antiapoptotic protein in vivo. AT-406 is a small molecule inhibitor of the IAP genes and also regulates the transcription of several genes. Here, we show that SnCs upregulate the antiapoptotic proteins c-IAP1, c-IAP2 and XIAP.The combined inhibition of c-IAP1, c-IAP2 and XIAP using siRNA or AT-406 specifically induce the apoptosis of SnCs.In addition, XIAP and STX17 bind to each other to regulate the fusion of autophagosomes and lysosomes in SnCs, which in turn, affects the fate of SnCs. It is worth noting that the clearance of SnCs attenuated the secretion of SASP and created a proregenerative environment. Most importantly, local clearance of SnCs significantly attenuated the progression of osteoarthritis in rats without significant toxic effects. Thus, local elimination of SnCs may be a potential treatment for OA. This is the first report of inhibition of IAPs for clearing SnCs and suggests that eradication of SnCs may be a new strategy for the treatment of age-related diseases.

Porous Se@SiO2 nanocomposites for treatment of steroid-induced osteonecrosis of the femoral head / 中国组织工程研究

BACKGROUND:Steroid-induced osteonecrosis of the femoral head (SONFH) is a common bone disease characterized as high morbidity and poor prognosis,but the pathogenesis is unclear.Oxidative stress treatment is closely related to the occurrence and development of SONFH,and has tremendous potential in the treatment of SONFH,which can be realized by Nano-Se.OBJECTIVE:To observe the protective effect of porous Se@SiO2 nanocomposite on chondrocytes by antioxidant stress,and to further explore its mechanism of protection and treatment of SONFH.METHODS:(1) In vitro experiment:The rat chondrocytes were isolated,cultured and identified.Then,the chondrocytes were cultured with porous Se@SiO2 nanocomposite to suppress the production of reactive oxygen species (ROS).(2) In vivo experiment:A total of 36 rats were randomly divided into three groups.Steroid-induced group and experimental group were treated with intraperitoneal injection of lipopolysaccharide and intramuscular injection of methylprednisolone to induce SON FH models.Seven days after modeling,the experimental group was intraperitoneally injected with porous Se@SiO2 nanocomposite.No intervention was done in control group (blank control).At 8 weeks after modeling,rat bilateral femoral heads were taken for hematoxylin-eosin staining and Micro-CT scanning.RESULTS AND CONCLUSION:Results from the ROS detection and TUNEL apoptosis tests showed that the level of ROS in the chondrocytes was significantly reduced after intervention with Se@SiO2 (P ＜ 0.05).Micro-CT scanning findings showed that the bone mineral density,bone volume,bone area/bone volume,trabecular number,trabecular thickness,and trabecular separation in the steroid-induced and experimental groups were significantly different from those in the control group (P ＜ 0.05).Hematoxylin-eosin staining results showed smooth femoral head,normal bone cells,chondrocytes and trabecular bone,as well as few empty bone lacunae and fat cells in the control group,while in the steroid-induced group,there was bone trabecular fracture,fat cell hypertrophy fusion,a large number of empty bone lacunae and obvious osteonecrosis.These manifestations were significantly improved in the experimental group.To conclude,the porous Se@SiO2 nanocomposite has good antioxidative stress ability,suppresses the ROS production and exerts therapeutic effects on SONFH.