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Both of nanoplastics (NPs) and Tetrabromobisphenol A (TBBPA) are organic pollutants widely detected in the environment and organisms. The large specific surface area of NPs makes them ideal vectors for carrying various toxicants, such as organic pollutants, metals, or other nanomaterials, posing potential threats to human health. This study used Caenorhabditis elegans (C. elegans) to investigate the neurodevelopmental toxicity induced by combined exposure of TBBPA and polystyrene NPs. Our results showed that combined exposure caused synergistic inhibitory effects on the survival rate, body length/width, and locomotor ability. Furthermore, the overproduction of reactive oxygen species (ROS), lipofuscin accumulation, and dopaminergic neuronal loss suggested that oxidative stress was involved in induction of neurodevelopmental toxicity in C. elegans. The expressions of Parkinson’s disease related gene (pink-1) and Alzheimer’s disease related gene (hop-1) were significantly increased after combined exposure of TBBPA and polystyrene NPs. Knock out of pink-1 and hop-1 genes alleviated the adverse effects such as growth retardation, locomotion deficits, dopaminergic loss, and oxidative stress induction, indicating that pink-1 and hop-1 genes play an important role in neurodevelopmental toxicity induced by TBBPA and polystyrene NPs. In conclusion, TBBPA and polystyrene NPs had synergistic effect on oxidative stress induction and neurodevelopmental toxicity in C. elegans, which was mediated through increased expressions of pink-1 and hop-1.

Hypoxia-inducible factor-1α (HIF-1α) plays central roles in the hypoxia response. It is highly expressed in multiple cancers, but not always correlated with hypoxia. Mutation of the von Hippel-Lindau (VHL) gene, which encodes an E3 ligase, contributes to the constructive activation of HIF-1α in specific tumor types, as exemplified by renal cell carcinoma; but how VHL wild-type tumors acquire this ability is not completely understood. Here, we found that the oncogene iASPP (inhibitor of apoptosis-simulating protein of p53) plays essential roles in such a context. Genetic inhibition of iASPP reduced tumor growth, accompanied by impaired angiogenesis, increased areas of tumor necrosis, and reduced glycolysis that was HIF-1α-dependent. These abilities of iASPP were validated by in vitro assays. Mechanistically, iASPP directly binds VHL at its β domain, a region also involved in HIF-1α binding, therefore blocking VHL's binding and the subsequent degradation of HIF-1α protein under normoxia. iASPP levels correlate with HIF-1α protein and vascular endothelial growth factor (VEGF) and the glucose transporter protein type 1(GLUT1), representative HIF-1α target genes, in human colon cancer tissues. Furthermore, inhibition of iASPP expression synergizes with low toxic dose of the HIF-1α inhibitor YC-1 to inhibit HIF-1α expression and tumor growth. Our findings suggest that iASPP contributes to HIF-1α activation in cancers, and that iASPP-mediated HIF-1α stabilization has potential as a therapeutic approach against cancer.

Numerous studies have revealed that ambient long-term exposure to fine particulate matter (PM

Long non-coding RNAs (lncRNAs) are emerging as essential players in multiple biological processes. Mitochondrial dynamics, comprising the continuous cycle of fission and fusion, are required for healthy mitochondria that function properly. Despite long-term recognition of its significance in cell-fate control, the mechanism underlying mitochondrial fusion is not completely understood, particularly regarding the involvement of lncRNAs. Here, we show that the lncRNA HITT (HIF-1α inhibitor at translation level), can specifically localize in mitochondria. Cells expressing higher levels of HITT contain fragmented mitochondria. Conversely, we show that HITT knockdown cells have more tubular mitochondria than is present in control cells. Mechanistically, we demonstrate HITT directly binds mitofusin-2 (MFN2), a core component that mediates mitochondrial outer membrane fusion, by the in vitro RNA pull-down and UV-cross-linking RNA-IP (CLIP) assays. In doing so, we found HITT disturbs MFN2 homo- or heterotypic complex formation, attenuating mitochondrial fusion. Under stress conditions, such as ultraviolet radiation, we in addition show HITT stability increases as a consequence of MiR-205 downregulation, inhibiting MFN2-mediated fusion and leading to apoptosis. Overall, our data provide significant insights into the roles of organelle (mitochondria)-specific resident lncRNAs in regulating mitochondrial fusion, and also reveal how such a mechanism controls cellular sensitivity to UV radiation-induced apoptosis.

N, N-dimethylformamide (DMF) is a widely existing harmful environmental pollutant from industrial emission which can threat human health for both occupational and general populations. Epidemiological and experimental studies have indicated liver as the primary target organ of DMF. However, the molecular mechanism under DMF-induced hepatoxicity remains unclear. In the present study, we identified that DMF could induce abnormal autophagy flux in cells. We also showed that DMF-induced mitochondrial dysfunction and lethal mitophagy which further leads to autophagic cell death. Next, miRNA microarray analysis identified miR-92a-1-5p as the most down-regulated miRNA upon DMF exposure. Mechanistically, miR-92a-1-5p regulated mitochondrial function and mitophagy by targeting mitochondrial protein BNIP3L. Exogenous miR-92a-1-5p significantly attenuated DMF-induced mitochondrial dysfunction and mitophagy in vitro and in vivo. Our study highlights the mechanistic link between miRNAs and mitophagy under environmental stress, which provided a new clue for the mitochondrial epigenetics mechanism on environmental toxicant-induced hepatoxicity.

Thermo-, pH- and glucose-responsive polymeric nanoparticles are of great interest in developing a self-regulated drug delivery system. The novel core-shell nanoparticles were synthesized by self-assembly of a phenylboronic acid-based block copolymer poly-(N-isopropylacrylamide)-block-poly(3-acrylamidophenylboronic acid) (PNIPAM136-b-PAPBA16) and a fluorescent complex glucosamine-poly(N-isopropylacrylamide)/Eu(III) (GA-PNIPAM)/Eu(III) based on the cross-linking between PBA- and GA-containing blocks in this work. The nanoparticles can be tuned via thermo-induced collapse or glucose-induced swelling at appropriate pH and temperatures; they had an average kinetic radius was about 80nm, and which showed excellent fluorescence. MTT assays revealed the nanocarriers had no significant cytotoxic response of the micelle when it was observed in the cell line over the concentration range from 0.1 to 1000 μg/ml at any exposure times., GRAPHICAL ABSTRACT 10.1080/14686996.2019.1700394-UF0001

Increasing evidence has indicated that long noncoding RNAs (lncRNAs) play important roles in human diseases, including cancer; however, only a few of them have been experimentally validated and functionally annotated. Here, we identify a novel lncRNA that we term HITT (HIF-1α inhibitor at translation level). HITT is commonly decreased in multiple human cancers. Decreased HITT is associated with advanced stages of colon cancer. Restoration of the expression of HITT in cancer cells inhibits angiogenesis and tumor growth in vivo in an HIF-1α-dependent manner. Further study reveals that HITT inhibits HIF-1α expression, mainly by interfering with its translation. Mechanically, HITT titrates away YB-1 from the 5'-UTR of HIF-1α mRNA via a high-stringency YB-1-binding motif. The reverse correlation between HITT and HIF-1α expression is further validated in human colon cancer tissues. Moreover, HITT is one of the most altered lncRNAs upon the hypoxic switch and HITT downregulation is required for hypoxia-induced HIF-1α expression. We further demonstrate that HITT and HIF-1α form an autoregulatory feedback loop where HIF-1α destabilizes HITT by inducing MiR-205, which directly targets HITT for degradation. Together, these results expand our understanding of the cancer-associated functions of lncRNAs, highlighting the HITT-HIF-1α axis as constituting an additional layer of regulation of angiogenesis and tumor growth, with potential implications for therapeutic targeting.

Isoniazid (INH), an effective first-line drug for tuberculosis treatment, has been reported to be associated with hepatotoxicity for decades, but the underlying mechanisms are poorly understood. N-acetyltransferase 2 (NAT2) is a Phase II enzyme that specifically catalyzes the acetylation of INH, and NAT2 expression/activity play pivotal roles in INH metabolism, drug efficacy, and toxicity. In this study, we systematically investigated the regulatory roles of microRNA (miRNA) in NAT2 expression and INH-induced liver injury via a series of in silico, in vitro, and in vivo analyses. Four mature miRNAs, including hsa-miR-15a-3p, hsa-miR-628-5p, hsa-miR-1262, and hsa-miR-3132, were predicted to target the NAT2 transcript, and a negative correlation was observed between hsa-miR-15a-3p and NAT2 transcripts in liver samples. Further experiments serially revealed that hsa-miR-15a-3p was able to interact with the 3′-untranslated region (UTR) of NAT2 directly, suppressed the endogenous NAT2 expression, and then inhibited INH-induced NAT2 overexpression as well as INH-induced liver injury, both in liver cells and mouse model. In summary, our results identified hsa-miR-15a-3p as a novel epigenetic factor modulating NAT2 expression and as a protective module against INH-induced liver injury, and provided new clues to elucidate the epigenetic regulatory mechanisms concerning drug-induced liver injury (DILI).

Lactic acid acidifies the tumor microenvironment and promotes multiple critical oncogenic processes, including immune evasion. Pyruvate kinase M2 (PKM2) is a dominant form of pyruvate kinase (PK) expressed in cancers that plays essential roles in metabolic reprograming and lactate production, rendering it as an attractive therapeutic target of cancer. However, the mechanism underlying PKM2 regulation remains unclear. Here, we show that long noncoding RNA (lncRNA) HIF-1 α inhibitor at transcription level (HITT) inhibits lactate production in a PKM2-dependent manner. Mechanistically, it physically interacts with PKM2 mapped to a region that has been involved in both dimer (less-active) and tetramer (more-active) formation, inhibiting PKM2 oligomerization and leading to dramatic reduction of PK activity. Under glucose starvation, HITT was reduced as a result of miR-106 induction, which subsequently facilitates PKM2 oligomerization and increases vulnerability to apoptosis under glucose starvation stress. In addition, the interaction also reduces lactate secretion from cancer cells, which subsequently polarizes macrophages toward an M2-like anti-inflammatory phenotype and thus possibly contributes to immune escape in vivo . This study highlights an important role of an lncRNA in regulating PKM2 activity and also reveals a metabolic regulatory effect of PKM2 on macrophage polarization.

In the field of industrial measurement and control, platinum resistance temperature signals are widely transmitted in the form of current signals. Platinum resistance temperature signals often need to participate in a variety of control or display process loops after being converted into current signals. The PT100 thermal resistance temperature signal isolation transmitter is mainly used for isolation and transmission of PT100 sensor signal. However, the transmitter has conversion errors and the conversion errors of different channels of the transmitter are generally different, so the current values of different output channels of the transmitter are generally inconsistent. With the long-term operation of the industrial process control system, this numerical difference may increase gradually be unbearable. To solve this problem, this paper proposes a design scheme of the isolation transmitter based on Field Programmable Gate Array(FPGA). In this design scheme, FPGA collects the current value of each output channel, runs the automation correction algorithm, adjusts the value of the output current dynamically, and finally makes the current value of each output channel remain consistent. The hardware implement and test of the current isolation transmitter are carried out and the test results show that this thermal resistance temperature signal transmitter implementation scheme is feasible.

15 patients successfully received submental artery perforator flaps with its pedicle elongated. The lesions were located in tongue,oropharynx,gingiva,mandible,auricle,infraorbital skin,buccal mucosa and parotid gland.All patients are satisfied with the reconstruction. 15 patients’ donor sites were recovered well and the flaps survival was 100% with no post-operation or further major complications occurred

The emerging data indicates that long noncoding RNAs (lncRNAs) are involved in fundamental biological processes, and their deregulation may lead to oncogenesis and other diseases. LncRNA fulfil its biological functions at least in part by interacting with distinctive proteins. Here, we described two methods to identify the direct or indirect interactions between lncRNA and proteins: cross-linking and immunoprecipitation (CLIP) and RNA pull-down assay. CLIP methods enable yield a list of lncRNAs that directly interact target protein in living cells, whereas immunoprecipitation of biotin-labeled RNA (RNA pull-down) assay represents a method for identification of proteins that directly and indirectly bind with a particular target lncRNA of interest.

Cytochrome P450 (CYP) enzymes play critical roles in drug transformation, and the total CYPs are markedly decreased in alcoholic hepatitis (AH), a fatal alcoholic liver disease. miRNAs are endogenous small noncoding RNAs that regulate many essential biological processes. Knowledge concerning miRNA regulation of CYPs in AH disease is limited. Here we presented the changes of key CYPs in liver samples of AH patients retrieved from GEO database, performed in silico prediction of miRNAs potentially targeting the dysregulated CYP transcripts, and deciphered a novel mechanism underlying miRNA mediated CYPs expression in liver cells. Nine miRNAs were predicted to regulate CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2J2, and CYP3A4, among which hsa-miR-148a-3p was selected as a case study. Biochemical and molecular evidences demonstrated that miR-148a promoted CYP2B6 expression by increasing mRNA stability via directly binding to the 3'UTR sequence, and that this positive posttranscriptional regulation was AGO1/2-dependent. Further, luciferase reporter gene assay and RNA secondary structure analysis illustrated that the seedless target site, not the seed target site, controlled miR-148a-mediated CYP2B6 upregulation. Moreover, we identified HNF4A as a liver-specific transcription factor of MIR-148A through EMSA and chromatin immunoprecipitation experiments. In conclusion, ethanol downregulated miR-148a in hepatocytes through HNF4A regulation, which eventually decreased CYP2B6 expression. Our finding will benefit the understanding of dysregulated drug metabolism in AH patients and highlight an unconventional mechanism for epigenetic regulation of CYP gene expression.

Acetaminophen (APAP) overdose is one of the leading causes of acute liver failure in the US and other developed countries, the molecular mechanisms of APAP-induced hepatotoxicity remain speculative. PIWI-interacting RNAs (piRNAs), a novel class of small non-coding RNAs, have been identified as epigenetic regulators of transposon silencing, mRNA deadenylation, and elimination. However, the functional role of piRNAs in APAP-induced liver injury remains unclear. In the current study, the piRNA profiles were constructed in HepaRG cells after APAP exposure, and the roles of piR-23210 in regulating nuclear receptors (NRs) expression, metabolizing enzymes expression, and consequently APAP-induced liver injury were systematically investigated. As a result, 57 upregulated piRNAs were identified after APAP exposure, indicating the stress-response characteristic of piRNA molecules. Subsequent in vitro and in vivo experiments proved that piR-23210 is a novel self-protective molecule that targets HNF1A and HNF4A transcripts by interacting with RNA binding protein Nucleolin (NCL), suppresses downstream CYPs (CYP2E1, CYP3A4, and CYP1A2) expression, and protects against APAP-induced liver injury. In conclusion, our findings provided new mechanistic clues revealing potential protective role of a piRNA against the hepatoxicity of APAP.

PM

The emerging data indicates that long noncoding RNAs (lncRNAs) are involved in fundamental biological processes, and their deregulation may lead to oncogenesis and other diseases. LncRNA fulfil its biological functions at least in part by interacting with distinctive proteins. Here, we described two methods to identify the direct or indirect interactions between lncRNA and proteins: cross-linking and immunoprecipitation (CLIP) and RNA pull-down assay. CLIP methods enable yield a list of lncRNAs that directly interact target protein in living cells, whereas immunoprecipitation of biotin-labeled RNA (RNA pull-down) assay represents a method for identification of proteins that directly and indirectly bind with a particular target lncRNA of interest.

In the field of industrial measurement and control, analog signals, such as pressure, temperature, valve opening, and flow, are widely transmitted in the form of current signals. Analog signals often need to participate in a variety of control or display process loops after being converted into current signals. To ensure the stable and reliable operation of the industrial process control system, the input current signal needs to be converted and output by an isolator. However, the isolator has conversion error and the conversion errors of different channels of the isolator are generally different, so the current values of different output channels of the isolator are generally inconsistent. With the long-term operation of the industrial process control system, this numerical difference may increase gradually be unbearable. To solve this problem, this paper proposes a design scheme of the current isolator based on FPGA. In this design scheme, FPGA collects the current value of each output channel, runs the automation correction algorithm, adjusts the value of the output current dynamically, and finally makes the current value of each output channel remain consistent. The hardware implement and test of the current isolator are carried out and the test results show that this isolator implementation scheme is feasible.

Bacteria were first detected in human tumors more than 100 years ago, but the characterization of the tumor microbiome has remained challenging because of its low biomass. We undertook a comprehensive analysis of the tumor microbiome, studying 1526 tumors and their adjacent normal tissues across seven cancer types, including breast, lung, ovary, pancreas, melanoma, bone, and brain tumors. We found that each tumor type has a distinct microbiome composition and that breast cancer has a particularly rich and diverse microbiome. The intratumor bacteria are mostly intracellular and are present in both cancer and immune cells. We also noted correlations between intratumor bacteria or their predicted functions with tumor types and subtypes, patients' smoking status, and the response to immunotherapy.

Mechanical phenotyping of complex cellular structures gives insight into the process and function of mechanotransduction in biological systems. Several methods have been developed to characterize intracellular elastic moduli, while direct viscoelastic characterization of intracellular structures is still challenging. Here, we develop a needle tip viscoelastic spectroscopy method to probe multidimensional mechanical phenotyping of intracellular structures during a mini-invasive penetrating process. Viscoelastic spectroscopy is determined by magnetically driven resonant vibration (about 15 kHz) with a tiny amplitude. It not only detects the unique dynamic stiffness, damping, and loss tangent of the cell membrane-cytoskeleton and nucleus-nuclear lamina but also bridges viscoelastic parameters between the mitotic phase and interphase. Self-defined dynamic mechanical ratios of these two phases can identify two malignant cervical cancer cell lines (HeLa-HPV18+, SiHa-HPV16+) whose membrane or nucleus elastic moduli are indistinguishable. This technique provides a quantitative method for studying mechanosensation, mechanotransduction, and mechanoresponse of intracellular structures from a dynamic mechanical perspective. This technique has the potential to become a reliable quantitative measurement method for dynamic mechanical studies of intracellular structures.

Cellular senescence is terminal cell cycle arrest that represents a prominent response to numerous anticancer therapies. The oncogene inhibitor of the apoptosis-stimulating protein of p53 (iASPP) plays essential roles in regulating cellular drug response by inhibiting apoptosis. However, whether or not it regulates chemotherapy-induced senescence (TIS) in cancer cells remains unclear. Here, using two commonly used cancer cell lines, HCT 116 and MCF-7, along with the xenograft mouse model, we found that iASPP inhibits senescence and also influences the senescence-associated secretory phenotype (SASP), which confers anticancer drug resistance independently of apoptosis. Mechanistically, iASPP is transcriptionally elevated by the p65 subunit of NF-κB in senescent cells and then translocates to the nucleus, where it binds p53 and NF-κBp65. This binding inhibits their transcriptional activities toward p21 and the key SASP factors interleukin (IL)-6/IL-8, respectively, and subsequently prevents senescence. Of note, we observed that iASPP knockdown sensitizes apoptosis-resistant cancers to doxorubicin treatment by promoting senescence both in vitro and in vivo. We conclude that iASPP integrates the NF-κBp65- and p53-signaling pathways and thereby regulates cell fate in response to TIS, leading to chemotherapy resistance. These findings suggest that iASPP inhibition might be a strategy that could help restore senescence in cancer cells and improve outcomes of chemotherapy-based therapies.

PM2.5 (particles matter smaller aerodynamic diameter of 2.5 μm) exposure, a major environmental risk factor for the global burden of diseases, is associated with high risks of respiratory diseases. Heme-oxygenase 1 (HMOX1) is one of the major molecular antioxidant defenses to mediate cytoprotective effects against diverse stressors, including PM2.5-induced toxicity; however, the regulatory mechanism of HMOX1 expression still needs to be elucidated. In this study, using PM2.5 as a typical stressor, we explored whether microRNAs (miRNAs) might modulate HMOX1 expression in lung cells. Systematic bioinformatics analysis showed that seven miRNAs have the potentials to target HMOX1 gene. Among these, hsa-miR-760 was identified as the most responsive miRNA to PM2.5 exposure. More importantly, we revealed a “non-conventional” miRNA function in hsa-miR-760 upregulating HMOX1 expression, by targeting the coding region and interacting with YBX1 protein. In addition, we observed that exogenous hsa-miR-760 effectively elevated HMOX1 expression, reduced the reactive oxygen agents (ROS) levels, and rescued the lung cells from PM2.5-induced apoptosis. Our results revealed that hsa-miR-760 might play an important role in protecting lung cells against PM2.5-induced toxicity, by elevating HMOX1 expression, and offered new clues to elucidate the diverse functions of miRNAs.

Ataxia-telangiectasia mutated (ATM) is an apical kinase of the DNA damage response following DNA double-strand breaks (DSBs); however, the mechanisms of ATM activation are not completely understood. Long noncoding RNAs (lncRNAs) are a class of regulatory molecules whose significant roles in DNA damage response have started to emerge. However, how lncRNA regulates ATM activity remains unknown. Here, we identify an inhibitor of ATM activation, lncRNA HITT (HIF-1α inhibitor at translation level). Mechanistically, HITT directly interacts with ATM at the HEAT repeat domain, blocking MRE11-RAD50-NBS1 complex–dependent ATM recruitment, leading to restrained homologous recombination repair and enhanced chemosensitization. Following DSBs, HITT is elevated mainly by the activation of Early Growth Response 1 (EGR1), resulting in retarded and restricted ATM activation. A reverse association between HITT and ATM activity was also detected in human colon cancer tissues. Furthermore, HITTs sensitize DNA damaging agent–induced cell death both in vitro and in vivo. These findings connect lncRNA directly to ATM activity regulation and reveal potential roles for HITT in sensitizing cancers to genotoxic treatment., ATM is a crucial kinase in the cellular response to double-strand DNA breaks, but its mechanism of activation is not fully understood. This study identifies a novel lncRNA, HITT, that plays an essential role in inhibiting ATM activity and sensitizes cancer cells to DNA-damaging agents.

WirelessHART network is an emerging wireless sensor network technology, famous for simplicity, safety, and reliability. WirelessHART network uses Time Division Media Access (TDMA) and Frequency Hopping Spread Spectrum (FHSS) access mechanism to avoid collisions and mitigate interference from other wireless networks. Many formulations of the link scheduling problem have been proven to be NP-complete, which is about how to assign slots and channels to links. In this paper, we propose a minimized buffered link scheduling algorithm for WirelessHART networks based on graph route (LBLSGR), which utilizes edge coloring to scheduling time slots according to the resource demand of nodes. We supply more communication resource to the nodes located nearer to the gateway, because of frequent packet forwarding. Utilizing this algorithm, the WirelessHART networks can make the average network delay least, the average network power assumption lower, and the packet buffers minimized. At last, the validity of our algorithm is proved and the test result is provided.

In view of the controlling issues such as the steering restraints on the water and the turbulence by wind, wave, current and else in the midst of voyage, this paper designed a type of surface USV heading controller on the basis of predictive function control principle. The controller adopted the thought of prediction prior to control. With full consideration of above mentioned restraints and disturbance that affect the heading control, when the optimum control quantity was solved online, it fulfilled timely compensation on the turbulence. After that, simulation experiment was carried on upon the heading controller that was steered by predictive function; moreover, in comparison with the heading controller that was steered by traditional PID, it validated the effectiveness of the newly designed controller. In addition, it provided support for subsequent design of indirect flight path algorithm.

At present, the track control of unmanned surface vessel (USV) is mainly divided into direct track control and indirect track control, both of which have their advantages in the aspect of USV track control. Though having high control precision, the former still fails to meet the related requirements. To tackle this problem, the nonlinear model predictive control (NMPC) algorithm was optimized based on the convolutional neural network (CNN) in order to design a direct USV track controller. In consideration of the nonlinearity and time lag problems that are likely to occur in USV track control, the convolutional neural network was used to solve the optimal control sequence of the predictive control algorithm. The simulation test indicates that this algorithm has effectively improved the accuracy and real-time performance of track control.

Renal cell carcinoma (RCC) is highly resistant to chemotherapies. The lack of efficacious treatment for metastatic RCC has led to a poor 5-year survival rate. Here, we found that Apoptosis-stimulating protein of p53-2(ASPP2) was frequently decreased in primary RCC tissues in comparison with non-tumoural kidney controls. Decreased ASPP2 was correlated with high grades and poor outcomes of RCC. Further studies revealed that ASPP2 downregulation promoted EMT and increased resistance to 5-Fluorouracil (5-FU)-induced apoptosis. To this end, the regulatory mechanisms of ASPP2 were further explored. Our data revealed that ASPP2 was inhibited by histone deacetylatlase 1 (HDAC1), which acted by preventing the binding between transcription factor (E2F1) and the ASPP2 promoter. Of particular importance, HDAC1 inhibitor vorinostat restored ASPP2 transcription and produced a synergistic effect with 5-FU in elevating ASPP2, promoting apoptosis and inhibiting EMT in both in vitro and in vivo RCC models. In summary, our data not only highlight an important role of ASPP2 in RCC progression and drug resistance, but also reveal new regulatory mechanisms of ASPP2, which provides important insights into novel treatment strategies by targeting ASPP2 dysregulation in RCC.

As promising drug delivery vehicles, previous investigations of liposomes as carriers are primarily focused on insertion and modification of lipid membrane interfaces. The utility of the inner core seems to be overlooked. Herein, we developed pH-sensitive liposomes (PSLs) containing an aqueous two phase system (ATPS), and intriguingly discovered their hierarchical release under acidic stimuli. ATPS containing two polymers (poly(ethylene glycol) (PEG) and dextran) is homogeneous above phase transition temperature when producing ATPS-liposomes, and separated into PEG-rich phase and dextran-rich phase after cooling down to room temperature. The overall release time of ATPS-liposomes is divided into two stages and prolonged compared to simple aqueous liposomes. The unique release profile is due to the disproportional distribution of drugs in two phases. Doxorubicin (DOX) is loaded in the ATPS-liposomes, and their half maximum inhibition concentration on HeLa cells is 0.018 μmol L-1, which means 27.5 fold increase in inhibition efficiency over free DOX.

Inactivation of p53 has been shown to correlate with drug resistance in tumors. However, in clear cell renal cell carcinoma (ccRCC), p53 is rarely mutated, yet the tumors remain highly insensitive to the conventional chemotherapeutic drugs. The underlying mechanisms responsible for the non-genetic p53 inactivation remain obscure. Here, we report, for the first time, that Apoptosis Stimulating of P53 Protein 1 (ASPP1) was remarkably downregulated at both mRNA (about 3.9-fold) and protein (about 4.9-fold) levels in ccRCC human specimens in comparison with the paired normal controls. In addition, lower ASPP1 was closely related to the higher grade of tumors and shorter life expectancy of ccRCC patients, both with p

The epithelial–mesenchymal transition (EMT) is one of the crucial procedures for cancer invasion and distal metastasis. Despite undergoing intensive studies, the mechanisms underlying EMT remain to be completely elucidated. Here, we identified that apoptosis-stimulating protein of p53-2 (ASPP2) is a novel target of MiR-205 in various cancers. Interestingly, the binding site of MiR-205 at the 3′-untranslated region of ASPP2 was highly conserved among different species. An inverse correlation between MiR-205 and ASPP2 was further observed in vivo in cervical cancers, suggesting MiR-205 may be an important physiological inhibitor of ASPP2. Hypoxia is a hallmark of solid tumor microenvironment and one of such conditions to induce EMT. Notably, MiR-205 was remarkably induced by hypoxia in cervical and lung cancer cells. A marked suppression of ASPP2 was observed simultaneously. Further studies confirmed that hypoxia-induced ASPP2 suppression was mainly attributed to the elevated MiR-205. Interestingly, the alteration of MiR-205/ASPP2 under hypoxia was accompanied with the decreased epithelial marker E-cadherin and increased mesenchymal marker Vimentin, as well as a morphological transition from the typical cobblestone-like appearance to the mesenchymal-like structure. More importantly, MiR-205 mimics or ASPP2 silencing similarly promoted EMT process. By contrast, ASPP2 recovery or MiR-205 inhibitor reversed MiR-205-dependent EMT. Further studies demonstrated that the newly revealed MiR-205/ASPP2 axis promoted cell migration and also increased cell proliferation both in vivo and in vitro. These data together implicated a critical impact of MiR-205/ASPP2 on promoting EMT. MiR-205/ASPP2 may be potential diagnostic and therapeutic biomarkers in cervical and lung cancers.

An intriguing biological question relating to cell signaling is how the inflammatory mediator NF-kB and the tumour suppressor protein p53 can be induced by similar triggers, like DNA damage or infection, yet have seemingly opposing or sometimes cooperative biological functions. For example, the NF-κB subunit RelA/p65 has been shown to inhibit apoptosis, whereas p53 induces apoptosis. One potential explanation may be their co-regulation by common cellular factors: inhibitor of Apoptosis Stimulating p53 Protein (iASPP) is one such common regulator of both RelA/p65 and p53. Here we show that iASPP is a novel substrate of caspases in response to apoptotic stimuli. Caspase cleaves the N-terminal region of iASPP at SSLD294 resulting in a prominent 80kDa fragment of iASPP. This caspase cleavage site is conserved in various species from zebrafish to Homo sapiens. The 80kDa fragment of iASPP translocates from the cytoplasm to the nucleus via the RaDAR nuclear import pathway, independent of p53. The 80kDa iASPP fragment can bind and inhibit p53 or RelA/p65 more efficiently than full-length iASPP. Overall, these data reveal a potential novel regulation of p53 and RelA/p65 activities in response to apoptotic stimuli.

Summary Reactive oxygen species (ROS) have emerged as important signaling molecules that play crucial roles in carcinogenesis and cytotoxic responses. Nrf2 is the master regulator of ROS balance. Thus, uncovering mechanisms of Nrf2 regulation is important for the development of alternative treatment strategies for cancers. Here, we demonstrate that iASPP, a known p53 inhibitor, lowers ROS independently of p53. Mechanistically, iASPP competes with Nrf2 for Keap1 binding via a DLT motif, leading to decreased Nrf2 ubiquitination and increased Nrf2 accumulation, nuclear translocation, and antioxidative transactivation. This iASPP-Keap1-Nrf2 axis promotes cancer growth and drug resistance both in vitro and in vivo . Thus, iASPP is an antioxidative factor and represents a promising target to improve cancer treatment, regardless of p53 status.