[Integrated Analysis of Soil Organic Matter Molecular Composition Changes Under Different Land Uses].

The application of biomarkers to study the molecular composition of soil organic matter (SOM) can be used to analyze the source and degradation of SOM and reveal the stability mechanism of soil organic carbon (SOC) at the molecular level. In order to further clarify the effects of different land use patterns (farmland, grassland, and forest) on the molecular composition of SOM, the changes in molecular composition of organic matter (free lipids, cutin, suberin, and lignin) on a global scale were studied using a meta-analysis method. The results showed that there were significant differences in the molecular composition of organic matter under different land use patterns. The contents of free lipids (n-alkanes, n-alkanols, n-alkanoic acids, and cyclic lipids), cutin, and lignin phenols in forest soil were significantly higher than those in grassland and farmland. There was no significant difference in the content of suberin between grassland and forest soil. The ratio of suberin to cutin in grassland was the highest, with an average of 2.96, and the averages of farmland and forest were 1.68 and 2.21, respectively. The ratio of syringic acid to syringaldehyde (Ad/Al)S and the ratio of vanillic acid to vanillin (Ad/Al)V of farmland soil were the largest, which were 1.25 and 1.58, respectively, and were significantly higher than those in grassland (0.46 and 0.69) and forest (0.78 and 0.7). The results of correlation analysis showed that in farmland soil, suberin was significantly correlated with mean annual precipitation (MAP) and clay; cutin was significantly correlated with clay; and lignin was significantly correlated with mean annual temperature (MAT), MAP, sand, and bulk density. In grassland soil, total free lipids were significantly correlated with MAP and bulk density; suberin and cutin were significantly correlated with MAT and MAP; and lignin was significantly correlated with MAP, pH, sand, and bulk density. However, only lignin was significantly correlated with MAP and sand in forest soils. Overall, the contents of SOC and molecular components in forest soil were higher under the three land use practices, and the contribution of plant roots to SOM in grassland soil was greater. In farmland soil, the degradation of lignin was accelerated due to human farming activities. Future research should focus on the regulation of soil physicochemical properties and climatic conditions on the molecular composition of SOM.

Low-dose imiquimod induces melanogenesis in melanoma cells through an ROS-mediated pathway.

BACKGROUND: Melanogenesis is the process of melanin maturation which not only protects skin from UV radiation but also plays an important role in antigenicity of melanomas. Imiquimod (IMQ) is a toll-like receptor 7 (TLR7) agonist that exhibits antiviral and anticancer activity. OBJECTIVE: To explore whether IMQ could induce melanogenesis in melanoma cells. METHODS: The mouse melanoma cell line B16F10, the mouse immortalized melanocyte Melan-A, and human melanoma cell lines MNT-1, C32 and A375 were utilized in this study. The pigmented level was observed by the centrifuged cell pellet. The intracellular and extracellular melanin levels were examined in the absorbance in NaOH-extracted cell lysate and cell-cultured medium, respectively. The expression of melanogenesis related proteins was examined by immunoblotting. The intracellular cyclic AMP amount was evaluated by the cAMP Glo assay kit. The activity of phosphodiesterase 4B (PDE4B) was investigated by CREB reporter assay with overexpressed PDE4B or not. RESULTS: We demonstrated that a low dose of IMQ could trigger melanogenesis in B16F10 cells. IMQ induced microphthalmia-associated transcription factor (MITF) nuclear translocation, upregulated the expression of melanogenesis-related proteins, increased tyrosinase (TYR) activity, and led to pigmentation in B16F10 cells. Next, we found that IMQ-induced melanogenesis was activated by excessive intracellular cAMP accumulation, which was regulated through IMQ-mediated PDE4B inhibition. Finally, IMQ-induced ROS production was found to be involved in melanogenesis by its control of PDE4B activity. CONCLUSIONS: Low dose of IMQ could activate melanogenesis through the ROS/PDE4B/PKA pathway in melanoma cells.

Comparison of senhance and da vinci robotic radical prostatectomy: short-term outcomes, learning curve, and cost analysis.

BACKGROUND: The Senhance® Robotic System is a new laparoscopy-based platform that has been increasingly used in radical prostatectomy (RP) procedures. The purpose of this study is to compare the outcome of Senhance RP (SRP) with da Vinci RP (DRP) cases. METHODS: From August 2019 to April 2022, we prospectively recruited 63 cases of SRP. We compared the perioperative data, postoperative complication rates, short-term surgical outcomes (3-month postoperative undetectable prostate-specific antigen (PSA) and incontinence rates), learning curves, and cost analysis with data from 63 matched da Vinci Xi RP cases. RESULTS: There was no difference in BL (180 versus 180 ml, p = 0.86) and postoperative surgical complication rate (Clavient -Dindo grade I-IV, 25.3 versus 22.2%, p = 0.21) between the SRP cases and the DRP. Regarding the oncologic and continence function, there was no difference between positive margin rate (36.5% versus 41.3%, p = 0.58), rate of undetectable PSA level at postoperative 3 months (68.3 versus 66.7%, p = 0.85), and incontinence rate (14.3 versus 15.9%, p = 1.0) at postoperative 3 months between the two cohorts. The learning curve showed a quick downward slope for laparoscopic experienced surgeons. The median pocket cost for SRP patients in our hospital was $4170, which was lower than $7675 for the DRP patients. CONCLUSIONS: Safety and short-term outcomes are comparable between SRP and DRP. For experienced LRP surgeons, using the Senhance system to perform RP is straightforward. With a more affordable price as its biggest advantage, the Senhance system may serve as a safe and effective alternative for robotic RP.

Survival outcomes and prognostic factors for first-line abiraterone acetate or enzalutamide in patients with metastatic castration-resistant prostate cancer.

PURPOSE: To investigate the survival outcomes of metastatic castration-resistant prostate cancer (mCRPC) patients receiving first-line novel androgen receptor axis-targeted therapies (ARATs) and prognostic factors for patient survival. METHODS: This retrospective study obtained data from 202 patients who started abiraterone acetate or enzalutamide as first-line therapy for mCRPC between 2016 and 2021 from a single academic center. The primary endpoint was overall survival (OS) defined as the interval from the start of ARAT to death, loss to follow-up, or the end of the study period. The secondary endpoints were PSA decline, PSA nadir, and time to nadir (TTN) after ARATs. Kaplan-Meier survival analyses were applied for depicting OS. Cox proportional hazards model with inversed probability of treatment weighing-adjustment was used to validate the effect of patient, disease, and treatment response factors on OS. RESULTS: Among 202 patients, 164 patients were treated with first-line ARATs alone and 38 patients received second-line chemotherapy. The median OS was not reached in patients with first-line ARATs alone and was 38.8 months in those with subsequent chemotherapy after failure from ARATs. OS was not different between the use of abiraterone and enzalutamide, though enzalutamide showed a higher rate of PSA decline ≧ 90% (56% versus 40%, p = 0.021) and longer TTN (5.5 versus 4.7 months, p = 0.019). Multivariable analysis showed that PSA nadir > 2 ng/mL [hazard ratio (HR) 7.04, p < 0.001] and TTN<7 months (HR 2.18, p = 0.012) were independently associated with shorter OS. Patients with both of these poor prognostic factors had worse OS compared to those who had 0-1 factors (HR 9.21, p < 0.001). CONCLUSIONS: Patients with mCRPC who received first-line ARATs had better survival if they had a PSA nadir[Formula: see text]2 ng/mL or a TTN[Formula: see text]7 months. Further study is needed to determine if an early switch in therapy for those in whom neither is achieved may impact OS.

BiTE-Secreting CAR-γδT as a Dual Targeting Strategy for the Treatment of Solid Tumors.

HLA-G is considered as an immune checkpoint protein and a tumor-associated antigen. In the previous work, it is reported that CAR-NK targeting of HLA-G can be used to treat certain solid tumors. However, the frequent co-expression of PD-L1 and HLA-G) and up-regulation of PD-L1 after adoptive immunotherapy may decrease the effectiveness of HLA-G-CAR. Therefore, simultaneous targeting of HLA-G and PD-L1 by multi-specific CAR could represent an appropriate solution. Furthermore, gamma-delta T (γδT) cells exhibit MHC-independent cytotoxicity against tumor cells and possess allogeneic potential. The utilization of nanobodies offers flexibility for CAR engineering and the ability to recognize novel epitopes. In this study, Vδ2 γδT cells are used as effector cells and electroporated with an mRNA-driven, nanobody-based HLA-G-CAR with a secreted PD-L1/CD3ε Bispecific T-cell engager (BiTE) construct (Nb-CAR.BiTE). Both in vivo and in vitro experiments reveal that the Nb-CAR.BiTE-γδT cells could effectively eliminate PD-L1 and/or HLA-G-positive solid tumors. The secreted PD-L1/CD3ε Nb-BiTE can not only redirect Nb-CAR-γδT but also recruit un-transduced bystander T cells against tumor cells expressing PD-L1, thereby enhancing the activity of Nb-CAR-γδT therapy. Furthermore, evidence is provided that Nb-CAR.BiTE redirectes γδT into tumor-implanted tissues and that the secreted Nb-BiTE is restricted to the tumor site without apparent toxicity.

Pemetrexed combined with dual immune checkpoint blockade enhances cytotoxic T lymphocytes against lung cancer.

Chemotherapy, in combination with immune checkpoint blockade (ICB) targeting to programmed death-1 (PD-1) or its ligand PD-L1, is one of the first-line treatments for patients with advanced non-small-cell lung cancer (NSCLC). However, a large proportion of patients, especially those with PD-L1 negative tumors, do not benefit from this treatment. This may be due to the existence of multiple immunosuppressive mechanisms other than the PD-1/PD-L1 axis. Human leukocyte antigen-G (HLA-G) has been identified as an immune checkpoint protein (ICP) and a neoexpressed tumor-associated antigen (TAA) in a large proportion of solid tumors. In this study, we evaluated the induction of HLA-G as well as PD-L1 using sublethal doses of chemotherapeutics including pemetrexed in different NSCLC cell lines. Except for gefitinib, most of the chemotherapeutic agents enhanced HLA-G and PD-L1 expression in a dose-dependent manner, whereas pemetrexed and carboplatin treatments showed the most consistent upregulation of PD-L1 and HLA-G in each cell line. In addition to protein levels, a novel finding of this study is that pemetrexed enhanced the glycosylation of HLA-G and PD-L1. Pemetrexed potentiated the cytotoxicity of cytotoxic T lymphocytes (CTLs) to treat NSCLC. Both in vitro and in vivo experiments revealed that CTL-mediated cytotoxicity was most pronounced when both anti-PD-L1 and anti-HLA-G ICBs were combined with pemetrexed treatment. In conclusion, anti-HLA-G could be an intervention strategy in addition to the anti-PD-1/PD-L1 pathway for NSCLC. Moreover, dual targeting of PD-L1 and HLA-G combined with pemetrexed might have a better extent of CTL-based immunotherapy.

CAR-T cells targeting HLA-G as potent therapeutic strategy for EGFR-mutated and overexpressed oral cancer.

Oral squamous cell carcinoma (OSCC) is a common malignancy in the world. Recently, scientists have focused on therapeutic strategies to determine the regulation of tumors and design molecules for specific targets. Some studies have demonstrated the clinical significance of human leukocyte antigen G (HLA-G) in malignancy and NLR family pyrin domain-containing 3 (NLRP3) inflammasome in promoting tumorigenesis in OSCC. This is the first study to investigate whether aberrant epidermal growth factor receptor (EGFR) induces HLA-G expression through NLRP3 inflammasome-mediated IL-1ß secretion in OSCC. Our results showed that the upregulation of NLRP3 inflammasome leads to abundant HLA-G in the cytoplasm and cell membrane of FaDu cells. In addition, we also generated anti-HLA-G chimeric antigen receptor (CAR)-T cells and provided evidence for their effects in EGFR-mutated and overexpressed oral cancer. Our results may be integrated with OSCC patient data to translate basic research into clinical significance and may lead to novel EGFR-aberrant OSCC treatment.

Risk of cognitive impairment in men with advanced prostate cancer treated with NHAs: A systematic review and network meta-analysis.

Novel hormonal agents (NHAs) have significantly improved outcomes in men with advanced prostate cancer. However, it remains unclear whether NHAs are associated with subsequent cognitive impairment. Thus, we sought to perform a network meta-analysis to compare the risk of cognitive impairment across NHA types. Databases (PubMed, Embase, Scopus, and Web of Science), trial registries (Clinicaltrial.gov), the European Medicines Agency, and the US Food and Drug Administration drug safety reports were searched from inception through July 30, 2021. Eligible studies were clinical trials evaluating the risk of cognitive impairment between NHAs and placebo/standard care. Two independent investigators extracted the data and performed quality assessments using the Cochrane Risk of Bias Tool and ROBINS-I. We estimated the risk ratios by the frequentist approach and calculated the ranking probabilities of all treatments with the surface under the cumulative ranking probabilities. The primary outcome and secondary outcome were odds ratio (OR) and incidence rate ratio of cognitive impairment, respectively. We identified 15 trials with 14,723 participants comparing HNAs with placebo/standard care. Treatments associated with cognitive impairment, from the most to the least, were enzalutamide (OR, 3.66; 95% confidence interval [CI], 2.84-4.73), apalutamide (OR, 1.76; 95% CI, 1.08-2.87), abiraterone acetate (OR, 1.64; 95% CI, 1.01-2.45), and darolutamide (OR, 1.11 95% CI, 0.51-2.39). After adjustment of treatment time duration, enzalutamide still had the highest risk of cognitive impairment with an incidence rate ratio of 2.17 (95% CI, 1.65-2.78). These findings suggest that NHAs, especially enzalutamide, may increase the risk of cognitive impairment compared with placebo/standard care.

Bladder Management Strategies for Urological Complications in Patients with Chronic Spinal Cord Injury.

Neurogenic lower urinary tract dysfunction, common in patients with chronic spinal cord injury, inevitably results in urological complications. To address neurogenic lower urinary tract dysfunction after spinal cord injury, proper and adequate bladder management is important in spinal cord injury rehabilitation, with the goal and priorities of the protection of upper urinary tract function, maintaining continence, preserving lower urinary tract function, improvement of SCI patients' quality of life, achieving compatibility with patients' lifestyles, and decreasing urological complications. This concise review aims to help urologists address neurogenic lower urinary tract dysfunction by focusing on the risks of long-term urological complications and the effects of different bladder management strategies on these complications based on scientifically supported knowledge.

Imiquimod-induced ROS production causes lysosomal membrane permeabilization and activates caspase-8-mediated apoptosis in skin cancer cells.

BACKGROUND: Lysosomal cell death is induced by lysosomal membrane permeabilization (LMP) and the subsequent release of lysosomal proteolytic enzymes, including cathepsins (CTSs), which results in mitochondrial dysfunction and apoptosis. Imiquimod (IMQ), a synthetic TLR7 ligand, has both antiviral and antitumor activity against various skin malignancies in clinical treatment. Previously, we demonstrated IMQ not only caused lysosomal dysfunction but also triggered lysosome biogenesis to achieve lysosomal adaptation in cancer cells. OBJECTIVE: To determine whether lysosomes are involved in IMQ-induced apoptosis. METHODS: The human skin cancer cell lines BCC, A375 and mouse melanoma cell line B16F10 were used in all experiments. Cell death was determined by the Cell Counting Kit-8 (CCK-8) assay and DNA content assay. Protein expression was determined by immunoblotting. Caspase-8 activity was assessed using a fluorescence caspase-8 kit and determined by flow cytometry and confocal microscopy. RESULTS: IMQ not only induced lysosome damage but also abrogated lysosome function in skin cancer cells. IMQ-induced caspase-8 activation contributed to the processes of lysosomal cell death. Moreover, the use of ROS scavengers significantly abolished caspase-8 activation and inhibited IMQ-induced LMP. Additionally, pharmacological inhibition of CTSD not only abrogated caspase-8 activation but also rescued IMQ-induced cell death. Finally, lysosome-alkalizing agents enhanced the cytotoxicity of IMQ in vitro and in vivo. CONCLUSIONS: IMQ-induced ROS accumulation promotes LMP, releases CTSs into the cytosol, stimulates caspase-8 activation and finally causes lysosomal cell death. Lysosomal cell death and the CTSD/caspase-8 axis may play a crucial role in IMQ-induced cell death.

Comparative risk of herpes zoster in patients with psoriatic disease on systemic treatments: a systematic review and network meta-analysis.

Background: Numerous previous studies have examined risk of herpes zoster (HZ) in psoriatic disease; however, the results of these studies are conflicting and the relative risks associated with different treatments remain largely unknown. In this meta-analysis, we examined the relative risk of HZ associated with systemic treatments for psoriatic disease. Methods: PubMed, EMBASE, Cochrane Library, and Web of Science databases were searched to identify relevant English-language studies published up to April 2021. Data were extracted using a standardized data extraction form. Network meta-analyses (NMA) was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. We examined the differences in HZ risk (incidence rate ratio; IRR) between treatments using a random-effects model for direct pairwise comparisons and NMA. The surface under the cumulative ranking area was calculated to rank the HZ risk for each treatment condition. Results: This study analyzed 13 studies including 19 treatment arms involving a total of 443,104 patients with psoriatic disease. Corticosteroids (CS) [IRR, 2.56; 95% confidence interval (CI), 1.59-4.13], a Janus kinase inhibitor (JAKi; tofacitinib) (IRR, 2.34; 95% CI, 1.03-5.32), infliximab (IRR, 2.32; 95% CI, 1.27-4.21), conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) + CS (IRR, 2.26; 95% CI, 1.23-4.17), anti-tumor necrosis factor-α (anti-TNF-α) + csDMARDs and/or CS (IRR, 2.13; 95% CI, 1.38-3.31), csDMARDs (IRR, 1.62; 95% CI, 1.18-2.22), and anti-TNF-α except infliximab (IRR, 1.61; 95% CI, 1.13-2.30) were all associated with a significantly higher HZ risk compared to controls. CS treatment possessed the highest HZ risk, followed by infliximab and JAKi (tofacitinib). Phosphodiesterase-4 inhibitor, anti-interleukin-17, -23 or -12/23, phototherapy, and acitretin showed a risk similar to controls without significant differences. Conclusion: The NMA demonstrated CS, infliximab, and JAKi (tofacitinib), and several combination treatments were associated with higher HZ risk in patients with psoriasis and psoriatic arthritis. Differences in HZ risk should be taken into consideration when considering optimal psoriasis treatment.

Targeting human leukocyte antigen G with chimeric antigen receptors of natural killer cells convert immunosuppression to ablate solid tumors.

BACKGROUND: Immunotherapy against solid tumors has long been hampered by the development of immunosuppressive tumor microenvironment, and the lack of a specific tumor-associated antigen that could be targeted in different kinds of solid tumors. Human leukocyte antigen G (HLA-G) is an immune checkpoint protein (ICP) that is neoexpressed in most tumor cells as a way to evade immune attack and has been recently demonstrated as a useful target for chimeric antigen receptor (CAR)-T therapy of leukemia by in vitro studies. Here, we design and test for targeting HLA-G in solid tumors using a CAR strategy. METHODS: We developed a novel CAR strategy using natural killer (NK) cell as effector cells, featuring enhanced cytolytic effect via DAP12-based intracellular signal amplification. A single-chain variable fragment (scFv) against HLA-G is designed as the targeting moiety, and the construct is tested both in vitro and in vivo on four different solid tumor models. We also evaluated the synergy of this anti-HLA-G CAR-NK strategy with low-dose chemotherapy as combination therapy. RESULTS: HLA-G CAR-transduced NK cells present effective cytolysis of breast, brain, pancreatic, and ovarian cancer cells in vitro, as well as reduced xenograft tumor growth with extended median survival in orthotopic mouse models. In tumor coculture assays, the anti-HLA-G scFv moiety promotes Syk/Zap70 activation of NK cells, suggesting reversal of the HLA-G-mediated immunosuppression and hence restoration of native NK cytolytic functions. Tumor expression of HLA-G can be further induced using low-dose chemotherapy, which when combined with anti-HLA-G CAR-NK results in extensive tumor ablation both in vitro and in vivo. This upregulation of tumor HLA-G involves inhibition of DNMT1 and demethylation of transporter associated with antigen processing 1 promoter. CONCLUSIONS: Our novel CAR-NK strategy exploits the dual nature of HLA-G as both a tumor-associated neoantigen and an ICP to counteract tumor spread. Further ablation of tumors can be boosted when combined with administration of chemotherapeutic agents in clinical use. The readiness of this novel strategy envisions a wide applicability in treating solid tumors.

[Effects of Wheat Straw-derived Biochar Application on Soil Carbon Content Under Different Tillage Practices].

This study intended to examine the influence of biochar application on soil carbon content under different tillage conditions. For this, an indoor incubation experiment was performed with treatments included wheat straw-derived biochar application (0, 5, and 20 g·kg-1) and soil with different tillage measures (ploughing and no-tillage). The effects of biochar addition on soil organic carbon (SOC), dissolved organic carbon (DOC), soil microbial biomass carbon (MBC), readily oxidized organic carbon (ROC), soil inorganic carbon (SIC), pH, water soluble calcium and magnesium, and soil CO2 emissions were analyzed. The results showed that:① Compared with the control, the contents of SOC, ROC, DOC, and water soluble Ca and Mg increased by 20.3%-105.6%, 0.5%-36.0%, 0.8%-30.5%, 3.5%-42.3%, and 2.4%-75.2% in the no-tillage treatments, respectively; and the contents of SOC, ROC, DOC, water-soluble Ca and Mg increased by 29.2%-145.1%, 1.3%-63.9%, 2.4%-55.6%, 18.2%-89.8%, and 10.1%-150.5% in the ploughing treatment, respectively, under different dosage biochar amendments, and was enhanced with an increase in the biochar application amount. Cumulative CO2 emissions were highest with biochar amendment at 5 g·kg-1 under the no-tillage soil condition; however, this increased with an increase in the biochar amount in the ploughing treatment. At the end of incubation experiment, the soil MBC content increased by 35.5%-45.7% compared with the control treatment; however, there was no significant effect on soil pH and SIC between the treatments. ② Compared with the ploughing treatment, the cumulative CO2 emissions, SOC, ROC, DOC, MBC, and water-soluble Ca and Mg contents of the no tillage treatment increased by 34.2%-79.0%, 8.9%-45.5%, 28.2%-73.9%, 40.4%-78.4%, 0.2%-131.7%, 8.7%-39.8%, and 0.3%-61.0%, respectively, while soil pH and SIC decreased by 0.08-0.17 unit and 2.4%-13.9%, respectively, under the same biochar amendment treatments. Overall, the addition of biochar significantly increased soil organic carbon, active organic carbon, soil water soluble calcium and magnesium content, and soil cumulative CO2 emissions, but no significant effect was observed on soil inorganic carbon content.

Exosomal HMGB1 Promoted Cancer Malignancy.

Reciprocal crosstalk between platelets and malignancies underscores the potential of antiplatelet therapy in cancer treatment. In this study, we found that human chronic myeloid leukemia K562 cell-differentiated megakaryocytes and murine platelets produced bioactive substances and these are released into the extracellular space, partly in their exosomal form. High-mobility group box 1 (HMGB1) is a type of exosomal cargo, and the antiplatelet drugs aspirin and dipyridamole interfered with its incorporation into the exosomes. Those released substances and exosomes, along with exogenous HMGB1, promoted cancer cell survival and protected cells from doxorubicin cytotoxicity. In a tumor-bearing model established using murine Lewis lung carcinoma (LLC) cells and C57BL/6 mice, the tumor suppressive effect of dipyridamole correlated well with decreased circulating white blood cells, soluble P-selectin, TGF-ß1 (Transforming Growth Factor-ß1), exosomes, and exosomal HMGB1, as well as tumor platelet infiltration. Exosome release inhibitor GW4869 exhibited suppressive effects as well. The suppressive effect of dipyridamole on cancer cell survival was paralleled by a reduction of HMGB1/receptor for advanced glycation end-products axis, and proliferation- and migration-related ß-catenin, Yes-associated protein 1, Runt-related transcription factor 2, and TGF- ß1/Smad signals. Therefore, exosomes and exosomal HMGB1 appear to have roles in platelet-driven cancer malignancy and represent targets of antiplatelet drugs in anticancer treatment.

Imiquimod Accelerated Antitumor Response by Targeting Lysosome Adaptation in Skin Cancer Cells.

Lysosomal adaptation is a cellular physiological process in which the number and function of lysosomes are regulated at the transcriptional and post-transcriptional levels in response to extracellular and/or intracellular cues or lysosomal damage. Imiquimod (IMQ), a synthetic toll-like receptor 7 ligand with hydrophobic and weak basic properties, exhibits both antitumor and antiviral activity against various skin malignancies as a clinical treatment. Interestingly, IMQ has been suggested to be highly concentrated in the lysosomes of plasmacytoid dendritic cells, indicating that IMQ could modulate lysosome function after sequestration in the lysosome. In this study, we found that IMQ not only induced lysosomal membrane permeabilization and dysfunction but also increased lysosome biogenesis to achieve lysosomal adaptation in cancer cells. IMQ-induced ROS production but not lysosomal sequestration of IMQ was the major cause of lysosomal adaptation. Moreover, IMQ-induced lysosomal adaptation occurred through lysosomal calcium ion release and activation of the calcineurin/TFEB axis to promote lysosome biogenesis. Finally, depletion of TFEB sensitized skin cancer cells to IMQ-induced apoptosis in vitro and in vivo. In summary, a disruption of lysosomal adaptation might represent a therapeutic strategy for synergistically enhancing the cytotoxicity of IMQ in skin cancer cells.

Imiquimod-induced ROS production disrupts the balance of mitochondrial dynamics and increases mitophagy in skin cancer cells.

BACKGROUND: Mitochondrial homeostasis is a highly dynamic process involving continuous fission and fusion cycles and mitophagy to maintain mitochondrial functionality. Imiquimod (IMQ), a Toll-like receptor (TLR) 7 ligand, is used to treat various skin malignancies. IMQ also induces apoptotic and autophagic cell death in various cancers through a TLR7-independent pathway. OBJECTIVE: To investigate whether IMQ-induced ROS production is involved in mitochondrial dysfunction, mitochondrial fragmentation and mitophagy in skin cancer cells. METHODS: BCC/KMC-1, B16F10 and A375 skin cancer cells, AGS gastric cancer cells and primary human keratinocytes were treated with 50 µg/mL IMQ. After 4 h, ROS were detected by CM-H2DCFDA, DHE, and MitoSOX Red staining. After 24 h, cell viability and the mitochondrial membrane potential were evaluated by a CCK-8 assay and JC-1 staining, respectively. Oxygen consumption was assessed with an Oroboros instrument. Mitochondrial morphology and mitophagy were evaluated by MitoTracker and LysoTracker staining. Mitochondrial dynamics markers, including MFN-1, DRP-1 and OPA1, and mitophagy markers, including LC3, S65-phosphorylated ubiquitin, PINK1 and TOM20, were detected by immunoblotting. RESULTS: IMQ not only induced severe ROS production but also resulted in increased mitochondrial membrane potential loss, mitochondrial fission and mitophagy and decreased oxygen consumption in skin cancer cells compared with normal keratinocytes. Pretreatment with the antioxidant NAC reduced IMQ-induced ROS production and attenuated IMQ-induced mitochondrial fission and mitophagy in skin cancer cells. CONCLUSIONS: IMQ-induced ROS might be associated with mitochondrial dysfunction, mitochondrial fission and mitophagy in cancer cells. Alleviating IMQ-induced ROS production would reduce mitochondrial fission-to-fusion skewing and further reduce IMQ-induced mitophagy.

Atorvastatin-induced senescence of hepatocellular carcinoma is mediated by downregulation of hTERT through the suppression of the IL-6/STAT3 pathway.

Hepatocellular carcinoma (HCC), a hepatic malignancy, has a poor prognosis and contributes to cancer-related death worldwide. Cellular senescence is an anticancer therapeutic strategy that causes irreversible cell cycle arrest and enables immune-mediated clearance of cancer cells. Atorvastatin, an HMG-CoA reductase inhibitor, has been shown to inhibit tumor growth and induce apoptosis or autophagy in malignant tumors. However, whether atorvastatin can induce HCC cell senescence and the mechanisms involved are poorly understood. The effects of atorvastatin-induced senescence were examined in both HCC cells and mouse xenograft models. The phenomenon and mechanism of senescence were examined by cell cycle analysis, senescence-associated ß-galactosidase (SA-ß-gal) staining and western blotting in HCC cells, and HCC tissues from mice were analyzed by immunohistochemical (IHC) staining. We demonstrated that atorvastatin induced cell growth inhibition and G0/G1 phase cell cycle arrest, leading to senescence in HCC cells. Atorvastatin-induced senescence was independent of p53, p14, and p16, and atorvastatin not only decreased the secretion of IL-6, a major senescence-associated secretory phenotype (SASP) factor, and the phosphorylation of STAT3 but also inhibited the expression of hTERT, a catalytic subunit of telomerase. Supplementation with exogenous IL-6 reversed both atorvastatin-induced suppression of STAT3 phosphorylation and hTERT expression and atorvastatin-induced senescence. Overexpression of constitutively activated STAT3 rescued HCC cells from atorvastatin-induced hTERT suppression and senescence. Moreover, atorvastatin decreased tumor growth in mouse xenograft models. Consistent with these results, atorvastatin decreased the IL-6, p-STAT3, and hTERT levels and increased ß-gal expression in tumor sections. Taken together, these data indicate that atorvastatin can induce atypical cellular senescence in HCC cells to inhibit tumor growth, an effect mediated by downregulation of hTERT through suppression of the IL-6/STAT3 pathway.

M2-like polarization of THP-1 monocyte-derived macrophages under chronic iron overload.

Macrophages are characterized by phenotypical and functional heterogeneity. In different microenvironments, macrophages can polarize into two types: classically activated macrophages (M1) or alternatively activated macrophages (M2). M1 macrophages are a well-known bacteriostatic macrophage, and conversely, M2 macrophages may play an important role in tumor growth and tissue remodeling. M1 macrophages have been reported to have high intracellular iron stores, while M2 macrophages contain lower intracellular iron. It has been well-described that disturbances of iron homeostasis are associated with altered immune function. Thus, it is important to investigate if chronic iron overload is capable of polarizing macrophages. Human monocytic leukemia THP-1 cells were maintained in culture medium that contained 100 µM ferrous sulfate heptahydrate (FeSO4) (I-THP-1) and differentiated into THP-1-derived macrophages (I-TDMs) by induction with phorbol 12-myristate 13-acetate (PMA). We characterized that I-TDMs not only enhanced the surface expression of CD163 and CD206 but also increased arginase and decreased iNOS protein expression. I-TDMs enhanced pSTAT6 expression and decreased pSTAT1 and NF-κB expressions. Furthermore, the gene expression profile of I-TDMs was comparable with M2 macrophages by performing human oligonucleotide DNA microarray analysis. Finally, functional assays demonstrated I-TDMs secreted higher levels of IL-10 but not M1 cytokines. Additionally, the conditional medium of I-TDMs had enhanced migration and increased invasion of A375 melanoma cells which was similar to the characteristics of tumor-associated macrophages. Taken together, we demonstrated that THP-1-derived macrophages polarized to a phenotype of M2-like characteristics when subjected to chronic iron overload.

Imiquimod Exerts Antitumor Effects by Inducing Immunogenic Cell Death and Is Enhanced by the Glycolytic Inhibitor 2-Deoxyglucose.

The induction of immunogenic cell death (ICD) in cancer cells triggers specific immune responses against the same cancer cells. Imiquimod (IMQ) is a synthetic ligand of toll-like receptor 7 that exerts antitumor activity by stimulating cell-mediated immunity or by directly inducing apoptosis. Whether IMQ causes tumors to undergo ICD and elicits a specific antitumor immune response is unknown. We demonstrated that IMQ-induced ICD-associated features, including the surface exposure of calreticulin and the secretion of adenosine triphosphate and HMGB1, were mediated by ROS and endoplasmic reticulum stress. In a B16F10 melanoma mouse model, vaccinating mice with IMQ-induced ICD cell lysate or directly injecting IMQ in situ reduced tumor growth that was mediated by inducing tumor-specific T-cell proliferation, promoting tumor-specific cytotoxic killing by CD8+ T cells, and increasing the infiltration of various immune cells into tumor lesions. The ICD-associated features were crucial in the induction of specific antitumor immunity in vivo. The glycolytic inhibitor 2-deoxyglucose enhanced IMQ-induced ICD-associated features and strengthened the antitumor immunity mediated by IMQ-induced ICD cell lysate in p53-mutant cancer cells, which were IMQ-resistant in vitro. We conclude that IMQ is an authentic ICD inducer and provide a concept connecting IMQ-induced cancer cell death and antitumor immune responses.

MicroRNA-203 diminishes the stemness of human colon cancer cells by suppressing GATA6 expression.

The interaction between hyaluronan and CD44, an important cancer stem-cell marker, stimulates various tumor cell-specific functions such as the stemness of tumor cells. microRNA-203 (miR-203) can be downregulated by this interaction in human colorectal cancer (CRC) cells, which increases their stemness; however, the underlying mechanism is not yet defined. Here, we show that overexpression and sequestration of miR-203 in HCT-116 and HT-29 human CRC cells reduces and enhances their stemness, respectively. We also show that GATA-binding factor 6 (GATA6) is a direct target of miR-203. Our results indicate that upregulated expression of this transcription factor not only restores the self-renewal abilities of miR-203-overexpressing HCT-116 and HT-29 cells but also promotes the stemness properties of their parental counterparts. More important, we show that silencing the expression of either LRH-1 or Hes-1 is sufficient to diminish the stemness-promoting effects of GATA6 in human CRC cells. Together, our findings delineate the stemness-inhibitory mechanism of miR-203 in human CRC cells and suggest that this miR is a potential therapeutic agent for colorectal cancer.