Rutin attenuates ensartinib-induced hepatotoxicity by non-transcriptional regulation of TXNIP.

Ensartinib, an approved ALK inhibitor, is used as a first-line therapy for advanced ALK-positive non-small cell lung cancer in China. However, the hepatotoxicity of ensartinib seriously limits its clinical application and the regulatory mechanism is still elusive. Here, through transcriptome analysis we found that transcriptional activation of TXNIP was the main cause of ensartinib-induced liver dysfunction. A high TXNIP level and abnormal TXNIP translocation severely impaired hepatic function via mitochondrial dysfunction and hepatocyte apoptosis, and TXNIP deficiency attenuated hepatocyte apoptosis under ensartinib treatment. The increase in TXNIP induced by ensartinib is related to AKT inhibition and is mediated by MondoA. Through screening potential TXNIP inhibitors, we found that the natural polyphenolic flavonoid rutin, unlike most reported TXNIP inhibitors can inhibit TXNIP by binding to TXNIP and partially promoting its proteasomal degradation. Further studies showed rutin can attenuate the hepatotoxicity of ensartinib without antagonizing its antitumor effects. Accordingly, we suggest that TXNIP is the key cause of ensartinib-induced hepatotoxicity and rutin is a potential clinically safe and feasible therapeutic strategy for TXNIP intervention.

Protective effect of borneol on the cutaneous toxicity of gilteritinib. / 吉列替尼皮肤毒性的机制及冰片的潜在保护作用.

OBJECTIVES: To investigate the effect of borneol on cutaneous toxicity of gilteritinib and to explore possible compounds that can intervene with the cutaneous toxicity. METHODS: C57BL/6J male mice were given gilteritinib by continuous gavage for 28 d and the damage to keratinocytes in the skin tissues was observed with hematoxylin and eosin (HE) staining, TUNEL assay and immunohistochemistry. Human keratinocytes HaCaT were treated with gilteritinib, and cell death and morphological changes were examined by SRB staining and microscopy; apoptosis of HaCaT cells was examined by Western blotting, flow cytometry with propidium iodide/AnnexinⅤ double staining and immunofluorescence; the accumulation of cellular reactive oxygen species (ROS) was examined by flow cytometry with DCFH-DA. Compounds that can effectively intervene the cutaneous toxicity of gilteritinib were screened from a natural compound library using SRB method, and the intervention effect of borneol on gilteritinib cutaneous toxicity was further investigated in HaCaT cells and C57BL/6J male mice. RESULTS: In vivo studies showed pathological changes in the skin with apoptosis of keratinocytes in the stratum spinosum and stratum granulosum in the modeling group. Invitro studies showed apoptosis of HaCaT cells, significant up-regulation of cleaved poly (ADP-ribose) polymerase (c-PARP) and gamma-H2A histone family member X (γ-H2AX) levels, and increased accumulation of ROS in gilteritinib-modeled skin keratinocytes compared with controls. Screening of the natural compound library revealed that borneol showed excellent intervention effects on the death of HaCaT cells. In vitro, cell apoptosis was significantly reduced in the borneol+gilteritinib group compared to the gilteritinib control group. The levels of c-PARP, γ-H2AX and ROS in cells were significantly decreased. In vivo, borneol alleviated gilteritinib-induced skin pathological changes and skin cell apoptosis in mice. CONCLUSIONS: Gilteritinib induces keratinocytes apoptosis by causing intracellular ROS accumulation, resulting in cutaneous toxicity. Borneol can ameliorate the cutaneous toxicity of gilteritinib by reducing the accumulation of ROS and apoptosis of keratinocytes in the skin tissue.

Regorafenib inhibits EphA2 phosphorylation and leads to liver damage via the ERK/MDM2/p53 axis.

The hepatotoxicity of regorafenib is one of the most noteworthy concerns for patients, however the mechanism is poorly understood. Hence, there is a lack of effective intervention strategies. Here, by comparing the target with sorafenib, we show that regorafenib-induced liver injury is mainly due to its nontherapeutic target Eph receptor A2 (EphA2). EphA2 deficiency attenuated liver damage and cell apoptosis under regorafenib treatment in male mice. Mechanistically, regorafenib inhibits EphA2 Ser897 phosphorylation and reduces ubiquitination of p53 by altering the intracellular localization of mouse double minute 2 (MDM2) by affecting the extracellular signal-regulated kinase (ERK)/MDM2 axis. Meanwhile, we found that schisandrin C, which can upregulate the phosphorylation of EphA2 at Ser897 also has protective effect against the toxicity in vivo. Collectively, our findings identify the inhibition of EphA2 Ser897 phosphorylation as a key cause of regorafenib-induced hepatotoxicity, and chemical activation of EphA2 Ser897 represents a potential therapeutic strategy to prevent regorafenib-induced hepatotoxicity.

Dasatinib causes keratinocyte apoptosis via inhibiting high mobility group Box 1-mediated mitophagy.

Dasatinib, a second-generation BCR-ABL inhibitor, is currently used as first-line treatment for patients with chronic myeloid leukemia. However, dasatinib treatment increases the risk of severe cutaneous toxicity, which limits its long-term safe use in clinic. The underlying mechanism for dasatinib-induced cutaneous toxicity has not been clarified. In this study, we tested the toxicity of dasatinib on human immortal keratinocyte line (HaCaT) and normal human epidermal keratinocytes (NHEK). We found that dasatinib directly caused cytotoxicity on keratinocytes, which could be the explanation of the clinical characteristic of pathology. Mechanistically, dasatinib impaired mitophagy by downregulating HMGB1 protein level in keratinocytes, which led to the accumulation of dysfunctional mitochondria. Mitochondria-derived ROS caused DNA damage and cell apoptosis. More importantly, we confirmed that overexpression of HMGB1 could reverse dasatinib-induced keratinocyte apoptosis, and preliminarily explored the intervention effect of saikosaponin A, which could increase HMGB1 expression, on cutaneous toxicity caused by dasatinib. Collectively, our study revealed that dasatinib induced keratinocyte apoptosis via inhibiting HMGB1-mediated mitophagy and saikosaponin A could be a viable strategy for prevention of dasatinib-induced cutaneous toxicity.

Regulation of p53 stability as a therapeutic strategy for cancer.

The tumor suppressor protein p53 participates in the control of key biological functions such as cell death, metabolic homeostasis and immune function, which are closely related to various diseases such as tumors, metabolic disorders, infection and neurodegeneration. The p53 gene is also mutated in approximately 50% of human cancer cells. Mutant p53 proteins escape from the ubiquitination-dependent degradation, gain oncogenic function and promote the carcinogenesis, malignant progression, metastasis and chemoresistance. Therefore, the stability of both wild type and mutant p53 needs to be precisely regulated to maintain normal functions and targeting the p53 stability is one of the therapeutic strategies against cancer. Here, we focus on compound-induced degradation of p53 by both the ubiquitination-dependent proteasome and autophagy-lysosome degradation pathways. We also review other posttranslational modifications which control the stability of p53 and the biological functions involved in these processes. This review provides the current theoretical basis for the regulation of p53 abundance and its possible applications in different diseases.

Enhanced proliferation inhibition and apoptosis in glioma cells elicited by combination of irinotecan and imatinib.

Glioma is a kind of lethal malignant tumor, and lacks efficient therapies. Combination therapy has been claimed to be a promising approach to combat cancer, due to its increased anti-cancer effects and reduced side effects. This study aimed to investigate the anti-cancer effect and mechanism of combining imatinib with irinotecan or its active metabolite 7-ethyl-10-hydroxycamptothecin (SN-38). First, we found that this drug combination exerted synergistic antitumor effects against glioma in vitro and in vivo. In addition, flow cytometry results proved that the SN-38-induced apoptosis was further enhanced by imatinib, and similar results were observed by determining the protein expression levels of apoptosis biomarkers. Interestingly, p53 expression was elevated by the SN-38 mono-treatment, and was not further increased after the co-treatment; besides, knockdown of p53 could only reduce the expression of cleaved-PARP partially, and weaken the enhanced proliferation inhibition induced by SN-38 plus imatinib, indicating that there might be other factors involved in the synergistic effects besides p53. Meanwhile, the markedly elevated p21 expression was observed only in the combination group, instead of the mono-treated groups. According to the results of p21 knockdown, we found that p21 was also required for the synergistic inhibitory effects. Moreover, we explored and ruled out the possibility of imatinib enhancing the sensitivity of irinotecan by inhibiting drug efflux pumps. Thus, our findings collectively suggest that combining irinotecan with imatinib could be a promising new strategy to fight against glioma.

Keratinocytes apoptosis contributes to crizotinib induced-erythroderma.

Crizotinib is a multi-target receptor tyrosine kinase inhibitor which is of great importance for the management of ALK-rearranged non-small cell lung cancer (NSCLC) patients. Serious erythroderma and toxic epidermal necrolysis have been reported associated with crizotinib treatment. The underlying mechanisms have not been examined. In this study, we tested the toxicity of crizotinib on immortal human keratinocytes (HaCaT) and human primary keratinocytes. We found that crizotinib directly cause cytotoxic on these two cells, which could be the explanation of the clinical characteristic of pathology. Apoptosis was observed and Z-VAD-FMK, a pan-caspase inhibitor can almost totally reverse the apoptosis induction effect of crizotinib. However, mitochondrial dysfunction and DNA damage were not involved in crizotinib-induced apoptosis, indicating the intrinsic apoptosis pathway have no connection with this cutaneous toxicity. Further studies showed that crizotinib significantly increased cleaved-caspase-8, a signaling protein of extrinsic apoptosis pathway, in a concentration and time-dependent manner. Moreover, we found the targets of crizotinib were not involved in HaCaT cells apoptosis. Collectively, our findings first report keratinocytes apoptosis is the key cause of crizotinib-induced cutaneous toxicity. We also reveal crizotinib induce apoptosis through the extrinsic apoptosis pathway due to detected up-regulated cleaved-caspase-8. Meanwhile, the apoptosis is independent of mitochondrial dysfunction, DNA damage and related drug targets inhibition.

Clinical practice guidelines for the management of neuropathic pain: a systematic review.

BACKGROUND: The management of neuropathic pain (NP) is challenging despite it being the recent focus of extensive research. A number of clinical practice guidelines (CPGs) for the management of NP have been published worldwide over the past 2 decades. This study aimed to assess the quality of these CPGs. METHODS: We performed a systematic review of published CPGs for the management of NP. Three reviewers independently assessed the quality of the CPGs using the Appraisal of Guidelines Research and Evaluation II (AGREE-II) instrument, and recommendations of CPGs were also appraised. RESULTS: A total of 16 CPGs were included. Thirteen CPGs were developed using an evidence-based approach, and the remaining CPGs were produced by consensus panels. None of CPGs obtained a score greater than 50% in all six AGREE II instrument domains mainly owing to poor performance in the "Applicability" domain. The highest score of the CPGs was achieved in "Clarity and Presentation" domain, followed by "Scope and Purpose" and "Editorial Independence" domains, and the lowest scores were found the in "Applicability" domain. The majority of the CPG recommendations on the management of patients with NP were relatively consistent, especially regarding the recommendation of stepwise treatment with medication. CONCLUSIONS: Greater efforts are needed not only to improve the quality of development and presentation of the CPGs, but also to provide more efficacy evidence for the management of patients with NP.

Enhanced osteointegration of orthopaedic implant gradient coating composed of bioactive glass and nanohydroxyapatite.

We conducted histologic and histomorphometric studies to evaluate the osteointegration of gradient coatings composed of bioactive glass and nanohydroxyapatite (BG-nHA) on titanium-alloy orthopaedic implants and surrounding bone tissue in vivo. Titanium-alloy implants with a gradient coating (gradient coating group), uncoated implants (uncoated group), and implants with a conventional hydroxyapatite (HA) coating (HA coating group) were randomly implanted in bilateral femoral condyles of 36 male New Zealand rabbits. The bone-implant contact at 12 and 24 weeks and the new bone volume in the notch created for observing bone ingrowth at 4, 12, and 24 weeks were found greater in the gradient coating group than those in both the uncoated group and the HA coating group (p < 0.05). Fluorescence micrographs showed active osteogenesis in the gradient coating group at 4 weeks after implantation. These findings indicated that BG-nHA gradient coatings could enhance the osteointegration of orthopaedic implant.