S670, an amide derivative of 3-O-acetyl-11-keto-ß-boswellic acid, induces ferroptosis in human glioblastoma cells by generating ROS and inhibiting STX17-mediated fusion of autophagosome and lysosome.

Glioblastoma (GBM) is the most common malignant tumor in the brain with temozolomide (TMZ) as the only approved chemotherapy agent. GBM is characterized by susceptibility to radiation and chemotherapy resistance and recurrence as well as low immunological response. There is an urgent need for new therapy to improve the outcome of GBM patients. We previously reported that 3-O-acetyl-11-keto-ß-boswellic acid (AKBA) inhibited the growth of GBM. In this study we characterized the anti-GBM effect of S670, a synthesized amide derivative of AKBA, and investigated the underlying mechanisms. We showed that S670 dose-dependently inhibited the proliferation of human GBM cell lines U87 and U251 with IC50 values of around 6 µM. Furthermore, we found that S670 (6 µM) markedly stimulated mitochondrial ROS generation and induced ferroptosis in the GBM cells. Moreover, S670 treatment induced ROS-mediated Nrf2 activation and TFEB nuclear translocation, promoting protective autophagosome and lysosome biogenesis in the GBM cells. On the other hand, S670 treatment significantly inhibited the expression of SXT17, thus impairing autophagosome-lysosome fusion and blocking autophagy flux, which exacerbated ROS accumulation and enhanced ferroptosis in the GBM cells. Administration of S670 (50 mg·kg-1·d-1, i.g.) for 12 days in a U87 mouse xenograft model significantly inhibited tumor growth with reduced Ki67 expression and increased LC3 and LAMP2 expression in the tumor tissues. Taken together, S670 induces ferroptosis by generating ROS and inhibiting STX17-mediated fusion of autophagosome and lysosome in GBM cells. S670 could serve as a drug candidate for the treatment of GBM.

A General Model to Explain Repeated Turnovers of Sex Determination in the Salicaceae.

Dioecy, the presence of separate sexes on distinct individuals, has evolved repeatedly in multiple plant lineages. However, the specific mechanisms by which sex systems evolve and their commonalities among plant species remain poorly understood. With both XY and ZW sex systems, the family Salicaceae provides a system to uncover the evolutionary forces driving sex chromosome turnovers. In this study, we performed a genome-wide association study to characterize sex determination in two Populus species, P. euphratica and P. alba. Our results reveal an XY system of sex determination on chromosome 14 of P. euphratica, and a ZW system on chromosome 19 of P. alba. We further assembled the corresponding sex-determination regions, and found that their sex chromosome turnovers may be driven by the repeated translocations of a Helitron-like transposon. During the translocation, this factor may have captured partial or intact sequences that are orthologous to a type-A cytokinin response regulator gene. Based on results from this and other recently published studies, we hypothesize that this gene may act as a master regulator of sex determination for the entire family. We propose a general model to explain how the XY and ZW sex systems in this family can be determined by the same RR gene. Our study provides new insights into the diversification of incipient sex chromosomes in flowering plants by showing how transposition and rearrangement of a single gene can control sex in both XY and ZW systems.

CDK1 serves as a therapeutic target of adrenocortical carcinoma via regulating epithelial-mesenchymal transition, G2/M phase transition, and PANoptosis.

BACKGROUND: Adrenocortical carcinoma (ACC) is an extremely rare, aggressive tumor with few effective therapeutic options or drugs. Mitotane (Mtn), which is the only authorized therapeutic drug, came out in 1970 and is still the only first-line treatment for ACC in spite of serious adverse reaction and a high recurrence rate. METHODS: By in silico analysis of the ACC dataset in the cancer genome atlas (TCGA), we determined that high expression levels of cyclin-dependent kinase-1 (CDK1) were significantly related to the adverse clinical outcomes of ACC. In vitro and in vivo experiments were performed to evaluate the role of CDK1 in ACC progression through gain and loss of function assays in ACC cells. CDK1 inhibitors were screened to identify potential candidates for the treatment of ACC. RNA sequencing, co-immunoprecipitation, and immunofluorescence assays were used to elucidate the mechanism. RESULTS: Overexpression of CDK1 in ACC cell lines promoted proliferation and induced the epithelial-to-mesenchymal transition (EMT), whereas knockdown of CDK1 expression inhibited growth of ACC cell lines. The CDK1 inhibitor, cucurbitacin E (CurE), had the best inhibitory effect with good time-and dose-dependent activity both in vitro and in vivo. CurE had a greater inhibitory effect on ACC xenografts in nude mice than mitotane, without obvious adverse effects. Most importantly, combined treatment with CurE and mitotane almost totally eliminated ACC tumors. With respect to mechanism, CDK1 facilitated the EMT of ACC cells via Slug and Twist and locked ACC cells into the G2/M checkpoint through interaction with UBE2C and AURKA/B. CDK1 also regulated pyroptosis, apoptosis, and necroptosis (PANoptosis) of ACC cells through binding with the PANoptosome in a ZBP1-dependent way. CONCLUSIONS: CDK1 could be exploited as an essential therapeutic target of ACC via regulating the EMT, the G2/M checkpoint, and PANoptosis. Thus, CurE may be a potential candidate drug for ACC therapy with good safety and efficacy, which will meet the great need of patients with ACC.

Anti-tumor effects of Skp2 inhibitor AAA-237 on NSCLC by arresting cell cycle at G0/G1 phase and inducing senescence.

Lung cancer is by far the leading cause of cancer death worldwide, and 85% of patients are diagnosed with non-small cell lung cancer (NSCLC), which is still very difficult to treat. Skp2 functions as an oncogene that participates in processes of many cancers. Here, we report a novel Skp2 inhibitor AAA-237 that binds to Skp2 protein and inhibits the proliferation of the NSCLC cells. We further investigated the anti-NSCLC mechanism of AAA-237 and found that it arrested the cell cycle at the G0/G1 phase by targeting Skp2 to reduce the degradation of p21Cip1 and p27Kip1 or by transcriptionally activating FOXO1 to increase the mRNA expression of p21Cip1 and p27Kip1. More importantly, we found that treatment of a high concentration AAA-237 could induce apoptosis of NSCLC cells and treatment of a low AAA-237 concentration for a longer time could induce senescence of NSCLC cells. Similar results were found in nude mice xenografted with A549 cells. AAA-237 inhibited tumor growth by inducing apoptosis and senescence in a dose-dependent manner. Considering these results, we propose that AAA-237 could be a promising therapeutic drug for treating patients with NSCLC.

Systematic pan-cancer analysis identifies APOC1 as an immunological biomarker which regulates macrophage polarization and promotes tumor metastasis.

Apolipoprotein C1 (APOC1) has been found to play an essential part in proliferation and metastasis of numerous cancers, but related mechanism has not been elucidated, especially its function and role in tumor immunity. Through systematic pan-cancer analysis, we identified that APOC1 was closely associated with the infiltration of various immune cells in multiple cancers. Besides, APOC1 was significantly co-expressed with the immune checkpoints, major histocompatibility complex (MHC) molecules, chemokines and other immune-related genes. Furthermore, single-cell sequencing analysis suggested that the vast majority of APOC1 was expressed in macrophages or tumor-associated macrophages (TAMs). Additionally, the expression of APOC1 was significantly related to the prognosis of different cancers. Since APOC1 was most significantly abnormally expressed in renal cell cancer (RCC), subsequent experiments were carried out in RCC to explore the role of APOC1 in tumor immunity. The expression of APOC1 was significantly elevated in the tumor and serum of RCC patients. Besides, APOC1 was mainly expressed in the macrophage and it was closely related to the immune cell infiltration of RCC. Co-culture with RCC cells could induce the generation of TAMs with M2 phenotype which be blocked by silencing APOC1. The expression of APOC1 was elevated in the M2 or TAMs and APOC1 promoted M2 polarization of macrophages through interacting with CD163 and CD206. Furthermore, macrophages overexpressing APOC1 promoted the metastasis of RCC cells via secreting CCL5. Together, these data indicate that APOC1 is an immunological biomarker which regulates macrophage polarization and promotes tumor metastasis.

ADH1C inhibits progression of colorectal cancer through the ADH1C/PHGDH /PSAT1/serine metabolic pathway.

Colorectal cancer (CRC) is the third most common cancer in men and the second most common cancer in women worldwide. CRC is the second leading cause of cancer-related deaths. Although some progress in the treatment of CRC has been achieved, the molecular mechanism of CRC is still unclear. In this study, alcohol dehydrogenase 1C(ADH1C) was first identified as a target gene closely associated with the development of CRC by the comprehensive application of transcriptomics, proteomics, metabonomics and in silico analysis. The ADH1C mRNA and protein expression in CRC cell lines and tumor tissues was lower than that in normal intestinal epithelial cell lines and healthy tissues. Overexpression of ADH1C inhibited the growth, migration, invasion and colony formation of CRC cell lines and prevented the growth of xenograft tumors in nude mice. The inhibitory effects of ADH1C on CRC cells in vitro were exerted by reducing the expression of PHGDH/PSAT1 and the serine level. This inhibition could be partially reversed by adding serine to the culture medium. These results showed that ADH1C is a potential drug target in CRC.

Benzimidazoles induce concurrent apoptosis and pyroptosis of human glioblastoma cells via arresting cell cycle.

Glioblastoma multiforme (GBM) is the most malignant and lethal primary brain tumor in adults accounting for about 50% of all gliomas. The only treatment available for GBM is the drug temozolomide, which unfortunately has frequent drug resistance issue. By analyzing the hub genes of GBM via weighted gene co-expression network analysis (WGCNA) of the cancer genome atlas (TCGA) dataset, and using the connectivity map (CMAP) platform for drug repurposing, we found that multiple azole compounds had potential anti-GBM activity. When their anti-GBM activity was examined, however, only three benzimidazole compounds, i.e. flubendazole, mebendazole and fenbendazole, potently and dose-dependently inhibited proliferation of U87 and U251 cells with IC50 values below 0.26 µM. Benzimidazoles (0.125-0.5 µM) dose-dependently suppressed DNA synthesis, cell migration and invasion, and regulated the expression of key epithelial-mesenchymal transition (EMT) markers in U87 and U251 cells. Benzimidazoles treatment also dose-dependently induced the GBM cell cycle arrest at the G2/M phase via the P53/P21/cyclin B1 pathway. Furthermore, the drugs triggered pyroptosis of GBM cells through the NF-κB/NLRP3/GSDMD pathway, and might also concurrently induced mitochondria-dependent apoptosis. In a nude mouse U87 cell xenograft model, administration of flubendazole (12.5, 25, and 50 mg · kg-1 · d-1, i.p, for 3 weeks) dose-dependently suppressed the tumor growth without obvious adverse effects. Taken together, our results demonstrated that benzimidazoles might be promising candidates for the treatment of GBM.

Apolipoprotein C1 promotes glioblastoma tumorigenesis by reducing KEAP1/NRF2 and CBS-regulated ferroptosis.

Glioblastoma (GBM), a malignant brain tumor, is a world-wide health problem because of its poor prognosis and high rates of recurrence and mortality. Apolipoprotein C1 (APOC1) is the smallest of apolipoproteins, implicated in many diseases. Recent studies have shown that APOC1 promotes tumorigenesis and development of several types of cancer. In this study we investigated the role of APOC1 in GBM tumorigenesis. Using in silico assays we showed that APOC1 was highly expressed in GBM tissues and its expression was closely related to GBM progression. We showed that APOC1 protein expression was markedly increased in four GBM cell lines (U251, U138, A172 and U87) compared to the normal brain glia cell lines (HEB, HA1800). In U251 cells, overexpression of APOC1 promoted cell proliferation, migration, invasion and colony information, which was reversed by APOC1 knockdown. APOC1 knockdown also markedly inhibited the growth of GBM xenografts in the ventricle of nude mice. We further demonstrated that APOC1 reduced ferroptosis by inhibiting KEAP1, promoting nuclear translocation of NRF2 and increasing expression of HO-1 and NQO1 in GBM cells. APOC1 also induced ferroptosis resistance by increasing cystathionine beta-synthase (CBS) expression, which promoted trans-sulfuration and increased GSH synthesis, ultimately leading to an increase in glutathione peroxidase-4 (GPX4). Thus, APOC1 plays a key role in GBM tumorigenesis, conferring resistance to ferroptosis, and may be a promising therapeutic target for GBM.

The U-box E3 ubiquitin ligase PalPUB79 positively regulates ABA-dependent drought tolerance via ubiquitination of PalWRKY77 in Populus.

The abscisic acid (ABA) signalling pathway is involved in the plant response to osmotic stress caused by drought and/or salinity. Although the ABA signalling pathway has been elucidated in Arabidopsis, it remains elusive in woody poplars. In this study, genome-wide analyses of U-box genes in poplars revealed that a U-box E3 ubiquitin ligase gene, PalPUB79, is significantly induced following drought, salinity and ABA signalling. PalPUB79 overexpression enhanced drought tolerance in transgenic poplars, while PalPUB79 RNAi lines were more sensitive to drought. PalPUB79 positively regulated ABA signalling pathway. Furthermore, PalPUB79 interacted with PalWRKY77, a negative transcriptional regulator of ABA signalling, and mediated its ubiquitination for degradation, therefore counteracting its inhibitory effect on PalRD26 transcription. However, the finding that PalWRKY77 negatively regulates PalPUB79 expression was indicative of a negative feedback loop between PalWRKY77 and PalPUB79 during ABA signalling in poplar. These findings provide novel insight into the mechanism through which PalPUB79 enhances the ABA-mediated stress response in woody poplars.

Avasimibe exerts anticancer effects on human glioblastoma cells via inducing cell apoptosis and cell cycle arrest.

Glioblastoma (GBM) is the most common and lethal primary brain tumor in adults, but there is no effective drug available for GBM. Avasimibe is a potent inhibitor of acyl-coenzyme A: cholesterol acyltransferase-1 (ACAT-1), which was used to treat atherosclerosis. Experimental evidence and bioinformatics have shown that avasimibe has anticancer activity. In this study we investigated the anticancer effects of avasimibe on human glioblastoma cells and the underlying mechanisms. Our results showed that avasimibe dose-dependently inhibited the proliferation of U251 and U87 human glioblastoma cells with IC50 values of 20.29 and 28.27 µM, respectively, at 48 h. Avasimibe (7.5, 15, 30 µM) decreased the DNA synthesis, and inhibited the colony formation of the tumor cells. Treatment of avasimibe also dose-dependently increased the apoptotic rate of tumor cells, decreased the mitochondrial membrane potential, induced the activity of caspase-3/7, and increased the protein expression of cleaved caspase-9, cleaved PARP and Bax in U251 and U87 cells. RNA-sequencing analyses revealed that avasimibe suppressed the expression of CDK2, cyclin E1, CDK4, cyclin D, CDK1, cyclin B1, Aurora A, and PLK1, while induced the expression of p53, p21, p27, and GADD45A, which was validated by Western blot analysis. These results demonstrated that avasimibe induced mitochondria-dependent apoptosis in glioblastoma cells, which was associated with arresting the cell cycle at G0/G1 phase and G2/M phase by regulating the p53/p21 pathway, p53/GADD45A and Aurora A/PLK1 signaling pathways. In U87 xenograft nude mice model, administration of avasimibe (15, 30 mg·kg-1·d-1, ip, for 18 days) dose-dependently inhibit the tumor growth. Taken together, our results demonstrated that avasimibe might be a promising chemotherapy drug in the treatment of GBM.

EZH2 regulates expression of FOXC1 by mediating H3K27me3 in breast cancers.

Triple-negative breast cancer (TNBC) is characterized by low expression of human epidermal growth factor receptor-2 (HER2), estrogen receptor (ER), and progesterone receptor (PR), which is the most aggressive subtype with poor outcome among breast cancers. The underlying mechanisms of TNBC remain unclear and there is a lack of biomarkers. In this study we conducted an in silico assay and found that FOXC1 was highly expressed in ER-/PR-/HER2- breast cancers, which was confirmed by qRT-PCR, immunohistochemistry, and Western blot analysis. FOXC1 was more highly expressed in TNBCs than the other breast cancers. Kaplan-Meier plotter revealed that expression of FOXC1 was associated with overall survival (OS) of patients with breast cancers. Expression of FOXC1 was reversely associated with level of H3K27me3, which was methylated by EZH2. In MCF-7 and T47D cells, inhibition of EZH2 by DZNeP or GSK343 concentration- and time-dependently increased expression of FOXC1. Finally, we demonstrated that the expression of FOXC1 was associated with resistance of doxorubicin treatment of breast cancer cells. In conclusion, these results suggest that FOXC1 may be a potential biomarker or drug target for TNBCs, and that downregulation of FOXC1 could have therapeutic value in treatment of TNBCs.

Novel Triazole Derivatives Containing Different Ester Skeleton: Design, Synthesis, Biological Evaluation and Molecular Docking.

Invasive fungal disease constitutes a growing health problem and development of novel antifungal drugs with high potency and selectivity are in an urgent need. In this study, a novel series of triazole derivatives containing different ester skeleton were designed and synthesized. Microdilution broth method was used to investigate antifungal activity. Significant inhibitory activity of compounds 5c, 5d, 5e, 5f, 5m and 5n was evaluated against the Candida albicans (I), Candida albicans clinical isolate (II), Candida glabrata clinical isolate (I), and Candida glabrata (II) with minimum inhibitory concentrations (MIC80) values ranging from 2 to 16 µg/mL. Notably, compounds 5e and 5n showed the best inhibition against Candida albicans (II), Candida glabrata (I), and Candida glabrata (II) at the concentrations of 2 and 8 µg/mL, respectively. Molecular docking study revealed that the target compounds interacted with CYP51 mainly through hydrophobic and van der Waals interactions. The results indicated that these novel triazole derivatives could serve as promising leads for development of antifungal agents.

Effects of Medical Chitosan on Capsular Formation Following Silicone Implant Insertion in a Rabbit Model.

BACKGROUND: Capsular contracture is a serious complication that occurs after breast implant surgery. This study was performed to confirm that medical chitosan (MC) affects capsule formation and elucidates a possible mechanism. MATERIALS AND METHODS: In this study, we used 18 female adult New Zealand White rabbits. In each rabbit, two silicone implants were placed under the pectoralis muscle layer on both sides (one side was included in the experimental group and the other side was included in the control group). MC was applied around the silicone implant of the experiment group, while the control group received no treatment. The capsular thickness was calculated by Masson's trichrome stain. The expression of MMPs and TIMPs were determined by real-time PCR, Western blotting, and immunohistochemistry. RESULTS: Compared to the control group, the capsular thickness of the MC group was significantly reduced at 4, 8, and 12 weeks after the operation (4 week: 229.3 ± 72.2 vs 76.1 ± 12.6 µm, p < 0.05; 8 week: 326.0 ± 53.8 vs 155.4 ± 61.7 µm, p < 0.0.5; 12 week: 151.2 ± 52.5 vs 60.0 ± 22.0 µm, p < 0.05). Compared to the control group, the MC group had significantly lower expressions of TIMP-1 and TIMP-2 (p < 0.05). However, compared to the control group, there was no statistically significant difference in the expressions of MMP-2 and MMP-9 in the experiment group (p > 0.05). CONCLUSION: MC reduced the risk of developing capsular contracture around silicone implants, possibly by blocking the signaling pathway of TIMPs. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Adipose tissue-derived stem cells treated with estradiol enhance survival of autologous fat transplants.

Autologous fat transplantation (AFT) is a common and important operation in plastic surgery for soft tissue defects and adipose tissue-derived stem cells (ADSCs) are considered as a promising supplement to decrease absorption and subsequent side effects due to the ability of multiple differentiation and production of vascular endothelial growth factor (VEGF). The capacities of ADSCs can be further enhanced by treatment with 17-ß estradiol (E2). Therefore, we hypothesized that E2 may promote the potential of ADSCs for AFT. In this study, ADSCs were extracted from three female patients by liposuction. In vitro studies showed that E2 supplementation at an optimal concentration of 10(-8) M resulted in enhanced proliferation, VEGF production, and adipogenic differentiation of human ADSCs, and reduced apoptosis rate in a serum-free environment. In addition, a nude mice model of fat transplantation was utilized to demonstrate the efficacy of ADSC for survival ratio in vivo. These results using the volume of fat tissues after 12 weeks compared original volume, revealed that the addition of E2-treated ADSCs induced a significantly higher tissue survival ratio (76.9 ± 1.9%) when compared with the ADSC-free system (55.5 ± 1.5%). Furthermore, increased capillary formation stained with hematoxylin-eosin (H&E) was observed in ADSCs systems after treatment with E2. Therefore, this study demonstrated E2 could promote the capacities of ADSCs about aspects of adipogenic differentiation, growth factor secretion and apoptosis reduction in vitro, vascularization improvement in vivo, and then enhanced the survival ratio of AFT.