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Ferroptosis is a lipid peroxidation-dependent cell death caused by metabolic dysfunction. Ferroptosis-associated enzymes are promising therapeutic targets for cancer treatment. However, such therapeutic strategies show limited efficacy due to drug resistance and other largely unknown underlying mechanisms. Here we report that cystine transporter SLC7A11 is upregulated in lung cancer stem-like cells (CSLC) and can be activated by stem cell transcriptional factor SOX2. Mutation of SOX2 binding site in SLC7A11 promoter reduced SLC7A11 expression and increased sensitivity to ferroptosis in cancer cells. Oxidation at Cys265 of SOX2 inhibited its activity and decreased the self-renewal capacity of CSLCs. Moreover, tumors with high SOX2 expression were more resistant to ferroptosis, and SLC7A11 expression was positively correlated with SOX2 in both mouse and human lung cancer tissue. Together, our study provides a mechanism by which cancer cells evade ferroptosis and suggests that oxidation of SOX2 can be a potential therapeutic target for cancer treatment.Significance:This study uncovers a SOX2–SLC7A11 regulatory axis that confers resistance to ferroptosis in lung cancer stem-like cells.

Ferroptosis is a lipid peroxidation-dependent cell death caused by metabolic dysfunction. Ferroptosis-associated enzymes are promising therapeutic targets for cancer treatment. However, such therapeutic strategies show limited efficacy due to drug resistance and other largely unknown underlying mechanisms. Here we report that cystine transporter SLC7A11 is upregulated in lung cancer stem-like cells (CSLC) and can be activated by stem cell transcriptional factor SOX2. Mutation of SOX2 binding site in SLC7A11 promoter reduced SLC7A11 expression and increased sensitivity to ferroptosis in cancer cells. Oxidation at Cys265 of SOX2 inhibited its activity and decreased the self-renewal capacity of CSLCs. Moreover, tumors with high SOX2 expression were more resistant to ferroptosis, and SLC7A11 expression was positively correlated with SOX2 in both mouse and human lung cancer tissue. Together, our study provides a mechanism by which cancer cells evade ferroptosis and suggests that oxidation of SOX2 can be a potential therapeutic target for cancer treatment. Significance: This study uncovers a SOX2–SLC7A11 regulatory axis that confers resistance to ferroptosis in lung cancer stem-like cells.

Ovarian cancer is the most lethal malignant tumor of female reproductive system. It is well-known that induction of STING-mediated type I interferons can enhance the resultant antitumor activity. However, STING pathway is usually inactivated in cancer cells at multiple levels. Here, we identified deubiquitinase USP35 is upregulated in ovarian cancer tissues. High level of USP35 was correlated with diminished CD8(+) T cell infiltration and poor prognosis in ovarian cancer patients. Mechanistically, we found that silencing USP35 reinforces the activation of STING-TBK1-IRF3 pathway and promotes the expression of type I interferons. Our data further showed that USP35 can directly deubiquitinate and inactivate STING. Interestingly, activation of STING promotes its binding to USP35 in a STING phosphorylation-dependent manner. Functionally, we found that knockdown of USP35 sensitizes ovarian cancer cells to the DNA-damage chemotherapeutic drug cisplatin. Overall, our study indicates that upregulation of USP35 may be a mechanism of the restricted STING activity in cancer cells, and highlights the significance of USP35 as a potential therapeutic target for ovarian cancer.

The content of medicinal components of Codonopsis pilosula differ greatly in various habitats. The development of specific molecular markers is of great significance for the identification of different varieties of C. pilosula . In this study, 1,379,041 primer pairs were designed based on the whole genome of C. lanceolata . Of these, 6 pairs of primers were able to amplify polymorphic bands. We performed genetic diversity analysis and constructed a cluster tree and DNA fingerprint of the three groups: mixed, wild and cultivated C. pilosula materials. The results were as follows: first, the mixed materials had an average observed number of alleles ( Na ) of 7.6667, an average effective number of alleles ( Ne ) of 4.6058, an average Shannon's information index ( I ) of 1.7128, an average expected homozygosty ( Exp Hom ) of 0.2118, an average expected heterozygosity ( Exp Het ) of 0.7882, an average expected heterozygosity of Nei’s ( Ht ) of 0.7798, and an average gene flow ( Nm ) of 0.1281. Second, the cultivated accessions were as follows: Na = 4.6667, Ne = 2.5956, I = 1.0702, Exp Hom = 0.4234, Exp Het = 0.5766, Ht = 0.5755, and Nm = 0.5253. Finally, the accessions of the wild materials were as follows: Na = 5.333, Ne = 2.8769, I = 1.2771, Exp Hom = 0.3556, Exp Het = 0.6444, Ht = 0.6433, and Nm = 0.5314. In addition, the results of cluster analysis showed that mixed, wild and cultivated materials were clustered into 4, 4 and 3 subgroups, respectively. Furthermore, we performed DNA fingerprinting of 47 mixed materials. These results are valuable for the identification and genetic analysis of C. pilosula from different sources in Shanxi Province.

Exposure to spaceflight and microgravity causes physiologic and psychologic changes including bone loss, cardiovascular dysfunction, and immune dysfunction. Anemia and hematopoietic disorders are observed in astronauts after spaceflight. Hematopoietic stem and progenitor cells (HSPCs), which can self-renew and give rise to all blood cells, play vital roles in hematopoiesis and homeostasis; however, the molecular mechanisms responsible for the impacts of microgravity on the proliferation of HSPCs remain unclear. We maintained mouse bone marrow HSPCs in the presence of stem cell factor for 12 d under spaceflight and simulated microgravity conditions, respectively, and analyzed cell proliferation and gene expression. Both spaceflight and simulated microgravity significantly decreased the number of HSPCs, mainly by blocking cell cycle at G(1)/S transition, but did not affect their differentiation abilities. RNA-sequencing data indicated that genes related to cell proliferation were down-regulated, whereas the genes related to cell death were up-regulated under microgravity. Among the gene signatures, we identified that the Kit-Ras/cAMP–cAMP response element-binding protein pathway might be one of the major microgravity-regulated pathways during HSPC proliferation. Furthermore, the quantification of notable genes was validated at the mRNA levels under simulated microgravity condition. Overall, these results would help us to understand the intracellular molecular mechanisms regulating microgravity-inhibited proliferation of HSPCs.—Wang, P., Tian, H., Zhang, J., Qian, J., Li, L., Shi, L., Zhao, Y. Spaceflight/microgravity inhibits the proliferation of hematopoietic stem cells by decreasing Kit-Ras/cAMP-CREB pathway networks as evidenced by RNA-Seq assays.

Spaceflight-associated immune system weakening ultimately limits the ability of humans to expand their presence beyond the earth's orbit. A mechanistic study of microgravity-regulated immune cell function is necessary to overcome this challenge. Here, we demonstrate that both spaceflight (real) and simulated microgravity significantly reduce macrophage differentiation, decrease macrophage quantity and functional polarization, and lead to metabolic reprogramming, as demonstrated by changes in gene expression profiles. Moreover, we identified RAS/ERK/NFκB as a major microgravity-regulated pathway. Exogenous ERK and NFκB activators significantly counteracted the effect of microgravity on macrophage differentiation. In addition, microgravity also affects the p53 pathway, which we verified by RT-qPCR and Western blot. Collectively, our data reveal a new mechanism for the effects of microgravity on macrophage development and provide potential molecular targets for the prevention or treatment of macrophage differentiation deficiency in spaceflight.

Hematopoietic stem cells (HSCs) are a major kind of pluripotent stem cells, which can give rise to all the other blood cells through the process of haematopoiesis and maintain the homeostasis of organism. HSCs are divided into three types based on their differentiation stage, including long-term self-renewing HSCs (LT-HSCs), short-term self-renewing HSCs (ST-HSCs) and multipotent progenitors (MPPs). These HSCs eventually differentiate into mature blood cells and immune cells after experiencing various common lymphoid progenitor (CLP) and common myeloid progenitor (CMP). The proliferation and differentiation of HSCs have been widely studied and revealed be controlled by various factors, molecules and transcription factors but litter is known about how microgravity affects HSCs. Our study was conducted in two flight programs, SJ-10 recoverable microgravity experimental satellite (SJ-10 satellite) program research and Tianzhou-1 cargo ship program, and mainly focuses on the maintaining and directed differentiation of hematopoietic stem cells. Our results revealed some new mechanisms for maintaining and directed differentiation under microgravity conditions, with the potential to boost immune system, and provide potential drugs for the prevention or treatment of immune system weakening in spaceflight.

Discrimination of species and geographical origins of traditional Chinese medicine (TCM) is essential to prevent adulteration and inferior problems. We studied Ephedra sinica Stapf, Ephedra intermedia Schrenk et C.A.Mey. and Ephedra przewalskii Bge. to investigate the relationship between inorganic element content and these three species and their geographical origins. 38 elemental fingerprints from six major Ephedra-producing regions, namely, Inner Mongolia, Ningxia, Gansu, Shanxi, Shaanxi, and Sinkiang, were determined to evaluate the importance of inorganic elements to three species and their geographical origins. The contents of 15 elements, namely, N, P, K, S, Ca, Mg, Fe, Mn, Na, Cl, Sr, Cu, Zn, B, and Mo, of Ephedra samples were measured using inductively coupled plasma mass spectroscopy. Elemental contents were used as chemical indicators to classify species and origins of Ephedra samples using a radar plot and multivariate data analysis, including hierarchical cluster analysis (HCA), principal component analysis (PCA), and discriminant analysis (DA). Ephedra samples from different species and geographical origins could be differentiated. This study showed that inorganic elemental fingerprint combined with multivariate statistical analysis is a promising tool for distinguishing three Ephedra species and their geographical origins, and this strategy might be an effective method for authenticity discrimination of TCM.

Molecular mechanisms of microgravity-caused immunosuppression are not fully elucidated. In the present study, we investigated the effects of simulated microgravity on macrophage functions and tried to identify the related intracellular signal pathways.Primary mouse macrophages were used in the present study. The gene expression and function of IL-4-treated mouse macrophages were detected after simulated microgravity or 1 g control.Freshly isolated primary mouse macrophages were cultured in a standard simulated microgravity situation using a rotary cell culture system (RCCS-1) and 1 g control conditions. Real-time PCR, western blots and flow cytometry were used to investigate the related intracellular signals and molecule expression.The arginase mRNA and protein levels in freshly isolated primary mouse macrophages under simulated microgravity using RCCS-1 were significantly higher than those under normal gravity. Meanwhile, simulated microgravity induced over-expression of C/EBPβ, a transcription factor of arginase promoter, and activation of p38 MAPK, which could increase C/EBPβ expression. Furthermore, up-regulation of Interleukin-6 (IL-6) and down-regulation of IL-12 p40 (IL-12B) in LPS-stimulated macrophages were also detected after simulated microgravity, which is regulated by C/EBPβ.Simulated microgravity activates a p38 MAPK-C/EBPβ pathway in macrophages to up-regulate arginase and IL-6 expression and down-regulate IL-12B expression. Both increased arginase expression and decreased IL-12B expression in macrophages during inflammation could result in immunosuppression under microgravity.

The quality control of Polygala tenuifolia Wild. is a major challenge in its clinical application. In this paper, a new strategy for the quality evaluation of P. tenuifolia extracts was verified through reverse-phase ultra-performance liquid chromatography (UPLC). The quantitative analysis of multi-components by a single marker (QAMS) was conducted with 3,6′-disinapoyl sucrose as an internal reference substance. Eight components (i.e., sibiricose A5, sibiricose A6, glomeratose A, tenuifoliside A, tenuifoliside B, tenuifoliside C, sibiricaxanthone B, and polygalaxanthone III) were determined based on the relative correction factors. The concentrations of these components were also determined by applying a conventional external standard method. The cosine value confirmed the consistency of the two methods (cosine ratio value >0.999920). Hierarchical cluster analysis, radar plots, and discriminant analysis were performed to classify 23 batches of P. tenuifolia extracts from Shanxi, Hebei, and Shaanxi in China. Results revealed that QAMS combined with radar plots and multivariate data analysis could accurately measure and clearly distinguish the different quality samples of P. tenuifolia. Hence, QAMS is a feasible and promising method for the quality control of P. tenuifolia.

Inorganic elements are important components of medicinal herbs, and provide valuable experimental evidence for the quality evaluation and control of traditional Chinese medicine (TCM). In this study, to investigate the relationship between the inorganic elemental fingerprint and geographical origin identification of cultivated Polygala tenuifolia, 41 elemental fingerprints of P. tenuifolia from four major polygala-producing regions (Shanxi, Hebei, Henan, and Shaanxi) were evaluated to determine the importance of inorganic elements to cultivated P. tenuifolia. A total of 15 elemental (B, Ca, Cl, Cu, Fe, K, Mg, Mn, Na, N, Mo, S, Sr, P, and Zn) concentrations of cultivated P. tenuifolia were measured using inductively coupled plasma mass spectroscopy (ICP-MS). The element composition samples were classified by radar plot, elemental fingerprint, and multivariate data analyses, such as hierarchical cluster analysis (HCA), principle component analysis (PCA), and discriminant analysis (DA). This study shows that radar plots and multivariate data analysis can satisfactorily distinguish the geographical origin of cultivated P. tenuifolia. Furthermore, PCA results revealed that N, Cu, K, Mo, Sr, Ca, and Zn are the characteristic elements of cultivated P. tenuifolia. Therefore, multi-element fingerprinting coupled with multivariate statistical techniques can be considered an effective tool to discriminate geographical origin of cultivated P. tenuifolia.

Microgravity environments in space can cause major abnormalities in human physiology, including decreased immunity. The underlying mechanisms of microgravity-induced inflammatory defects in macrophages are unclear.RAW264.7 cells and primary mouse macrophages were used in the present study. Lipopolysaccharide (LPS)-induced cytokine expression in mouse macrophages was detected under either simulated microgravity or 1g control.Freshly isolated primary mouse macrophages and RAW264.7 cells were cultured in a standard simulated microgravity situation using a rotary cell culture system (RCCS-1) and 1g control conditions. The cytokine expression was determined by real-time PCR and ELISA assays. Western blots were used to investigate the related intracellular signals.LPS-induced tumor necrosis factor-α (TNF-α) expression, but not interleukin-1β expression, in mouse macrophages was significantly suppressed under simulated microgravity. The molecular mechanism studies showed that LPS-induced intracellular signal transduction including phosphorylation of IKK and JNK and nuclear translocation of NF-κB in macrophages was identical under normal gravity and simulated microgravity. Furthermore, TNF-α mRNA stability did not decrease under simulated microgravity. Finally, we found that heat shock factor-1 (HSF1), a known repressor of TNF-α promoter, was markedly activated under simulated microgravity.Short-term treatment with microgravity caused significantly decreased TNF-α production. Microgravity-activated HSF1 may contribute to the decreased TNF-α expression in macrophages directly caused by microgravity, while the LPS-induced NF-κB pathway is resistant to microgravity.

Mineral elements serve as important components of medicinal herbs not only owing to their healing properties but also their nutritional supplement functions. In this study, 15 essential element contents of wild Ephedra sinica and its rhizosphere soil were measured by inductively coupled plasma mass spectroscopy. Influences of rhizosphere soil on these elements in plants were evaluated. Results showed that N, K, Cl, Sr, Na, Mn, B, Cu, and Mo contents in plants were all directly affected by one or more factors, including pH value, sand, silt, and organic matter contents. Herbaceous stems of E. sinica contained high contents of N, K, S, and Ca and could accumulate N, S, P, Cl, Sr, and Mg from soil with mean enrichment coefficients of 42.88, 34.37, 7.81, 4.38, 2.16, and 1.56, respectively. N, K, Ca, Sr, Mn, Zn, and Cu contents in the herbs were positively correlated with those in soil. Additionally, element prediction models were established to infer essential element contents of the herbaceous stems of E. sinica. This study provides scientific basis for mineral element regulation of E. sinica by adjusting soil fertility levels.

Macrophages acquire distinct phenotypes during tissue stress and inflammatory responses, but the mechanisms that regulate the macrophage polarization are poorly defined. Here we show that tuberous sclerosis complex 1 (TSC1) is a critical regulator of M1 and M2 phenotypes of macrophages. Mice with myeloid-specific deletion of TSC1 exhibit enhanced M1 response and spontaneously develop M1-related inflammatory disorders. However, TSC1-deficient mice are highly resistant to M2-polarized allergic asthma. Inhibition of the mammalian target of rapamycin (mTOR) fails to reverse the hypersensitive M1 response of TSC1-deficient macrophages, but efficiently rescues the defective M2 polarization. Deletion of mTOR also fails to reverse the enhanced inflammatory response of TSC1-deficient macrophages. Molecular studies indicate that TSC1 inhibits M1 polarization by suppressing the Ras GTPase-Raf1-MEK-ERK pathway in mTOR-independent manner, whereas TSC1 promotes M2 properties by mTOR-dependent CCAAT/enhancer-binding protein-β pathways. Overall, these findings define a key role for TSC1 in orchestrating macrophage polarization via mTOR-dependent and independent pathways.

Many landslides are triggered by rainfall in mountain areas especially in earthquake struck regions. To forecast these landslides, three questions need to be answered. Where and when will landslides occur? And what kind of slopes will slide? An early warning method based on statistical model integrated with landslide monitoring is proposed. Landslide susceptibility zonation gives the potential landslide location. With historical landslide and rainfall records, the correlation between them can be worked out with statistics analysis. Thus, the temporal possibility can be calculated when an intensive rainfall is coming. As for the specific slopes in high risk area, through some sensors can we learn the changes of surface displacement, internal displacement and soil moisture. Alarm or prediction can be deduced from the data. With this idea, a well-organized warning and monitoring system began to be built in west Chengdu, China. The victims and loss declined in 2010, which proved this method is useful.