[Comparative study of percutaneous transfacet screw and pedicle screw in oblique lumbar interbody fusion for the treatment of single-level lumbar spinal stenosis]

Objective: To conduct a comparative study of radiological and clinical outcomes between percutaneous transfacet screw (TFS) and pedicle screw (BPS) in oblique lateral lumbar interbody fusion (OLIF) for single-level lumbar spinal stenosis. Methods: A retrospective cohort study. Patients who underwent OLIF with TFS or BPS for the treatment of single-level lumbar spinal stenosis at Beijing Jishuitan Hospital from January 2019 to June 2022 were retrospectively analyzed. Radiological parameters and clinical indicators were compared between the two groups. Radiological parameters included preoperative, immediate postoperative (within 5 days), and 1-year postoperative measurements of disc height and segmental lordosis angle, as well as interbody fusion status at 1 year postoperatively. Clinical indicators included operative time, blood loss, length of hospital stay, complications, and Oswestry Disability Index (ODI), visual analogue scale (VAS) scores for back pain, and leg pain before and 1 year after surgery. Results: Four male and 10 female patients with an average age of (61.0±11.2) years underwent OLIF with TFS, while 9 male and 12 female patients underwent OLIF with BPS, with a mean age of (60.9±6.7) years. There was no statistically significant difference in preoperative disc height between the TFS and BPS groups (P>0.05). The immediate postoperative disc height was (12.9±2.1) mm and it was (10.4±1.7) mm at 1-year follow-up in the TFS group; in the BPS group, it was (12.9±2.1) mm immediately postoperatively and (11.9±2.1) mm at 1-year follow-up; there was statistically significant difference between the two groups at 1-year follow-up (P=0.037). The segmental lordosis angle showed no significant differences within each group or between the two groups at preoperative, immediate postoperative, or 1-year postoperative follow-up (all P>0.05). At 1-year postoperative follow-up, the fusion rates was 92.9%(13/14) in the TFS group and 95.2%(20/21) in the BPS group, with no statistically significant difference between the two groups (P>0.05). The TFS group had a significantly shorter operative time and less blood loss compared to the BPS group [(164.3±33.9) minutes vs (191.7±31.8) minutes and (74.3±46.9) ml vs (124.8±54.0) ml, respectively] (both P<0.05). Both groups showed significant improvement in ODI and VAS scores at 1 year postoperatively compared to those preoperatively, but with no statistically significant difference was found between the groups (both P>0.05). Conclusions: OLIF with TFS fixation can effectively restore disc height and alleviate back and leg pain in patients with single-level lumbar spinal stenosis. Compared to the OLIF with BPS procedure, OLIF with TFS has shorter operative time and less blood loss.

Association between infarct location and haemorrhagic transformation of acute ischaemic stroke after intravenous thrombolysis

AIM

To evaluate the association between computed tomography (CT)-based imaging variables at the time of admission and haemorrhagic transformation (HT) after intravenous thrombolysis (IVT).

MATERIALS AND METHODS

One hundred and eight patients who were treated with IVT for acute ischaemic stroke (AIS) during January 2021 to July 2023 were analysed retrospectively. The infarct location was classified as cortical or subcortical in accordance with the Alberta Stroke Program Early CT Score (ASPECTS) system. Logistic regression and receiver operating characteristic curve analyses were performed to determine the relationship between ischaemic variables and HT.

RESULTS

Of the total, 18 (16.7%) patients had HT and seven (6.5%) had symptomatic intracerebral haemorrhage (sICH). Multivariate analysis revealed that cortical ASPECTS was independently associated with HT (odds ratio [OR], 0.197; 95% confidence interval [CI], 0.076-0.511; p=0.001) and cortical ASPECTS was independently associated with sICH (OR, 0.066; 95% CI, 0.009-0.510; p=0.009). To predict HT and sICH, cortical ASPECTS (HT area under the curve [AUC] = 0.881, sICH AUC = 0.971) provided a higher AUC compared with ASPECTS (HT AUC = 0.850, sICH AUC = 0.918).

CONCLUSION

Cortical ASPECTS seen on CT at the time of admission is associated with HT and sICH after IVT.

[Current status and prospects for the application of robot-assisted spine surgery]

Traditional spine surgery frequently encounters difficulties with inadequate surgical visualization and high risk.Robot-assisted spine surgery is quickly evolving,particularly in screw placement,providing three-dimensional imaging and precise positioning to optimize the surgical process. Robot-assisted systems can increase surgical precision,reduce operating time and radiation exposure,and improve patient prognosis. They also have strong image recognition and analysis capabilities,reducing intraoperative instability and fatigue and allowing remote manipulation.While robot-assisted spine surgery has demonstrated noteworthy advantages in regards to screw placement accuracy and reduced radiation exposure,its effects on operative time remain subject to debate,with cost being a significant hindrance to widespread implementation.Long-term clinical validation and studies of outcomes are necessary for the extensive use of robotic-assisted spine surgery.Future priorities include the enhancement of surgical navigation and imaging,integration of artificial intelligence,improvement of telesurgical capabilities,expansion of robotic functionality,and the development of policy guidance and clinical guidelines to accompany the growth of technology.Robot-assisted spine surgery enhances accuracy and safety,and is anticipated to assume an increasingly crucial role in spine surgery as technology advances and becomes more widely available.

Association of blood heavy metal concentrations with hearing loss: a systematic review and meta-analysis

OBJECTIVES

This study aimed to assess the associations between blood heavy metal concentrations and hearing loss.

STUDY DESIGN

This was a systematic review and meta-analysis.

METHODS

A comprehensive literature search was performed using Embase, PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Chinese Biomedical Literature, Wanfang and Weipu databases. Ten studies were included, and a random or fixed-effects model was used for the meta-analysis. Review Manager 5.4 software was used for data synthesis, and Stata 15.1 software was used for the publication bias and sensitivity analyses.

RESULTS

Blood lead concentrations were significantly and substantially associated with hearing loss (mean difference (MD) = 1.14; 95% confidence interval [CI] = 0.03, 2.26; P = 0.04; I2 = 81%), and iron deficiency was significantly related to hearing loss (MD = -0.42; 95% CI = -0.66, -0.18; P = 0.12; I2 = 60%).

CONCLUSIONS

These results suggest an association between blood heavy metal concentrations and hearing loss. However, there were limitations: confounding factors, lack of description for the specific methods of blinding and independent verification of case definition, limited sample size, Chinese publications comprising half of the primary data and the lack of assessment of the relationship between different blood heavy metal concentrations and the severity of hearing loss. Therefore, larger and well-designed prospective cohort studies are required for further exploration.

[Serum glycocalyx markers in patients after cardiac arrest: association with outcomes]

Objective: To assess the levels of serum glycocalyx markers in the first 24 hours after cardiac arrest (CA) and investigate their relationship with 30-day outcomes. Methods: A retrospective cohort study was conducted on prospectively collected data from CA patients, who were admitted to the intensive care units of the Affiliated Hospital of Xuzhou Medical University and obtained return of spontaneous circulation for more than 24 hours between September 2021 and October 2022. Serum samples obtained at the 24-hour after CA were utilized to measure the levels of glycocalyx markers, including heparan sulfate (HS), hyaluronic acid (HA), and syndecan-1 (Sdc-1). Patients were allocated into good function (CPC1-2) and poor function (CPC3-5) groups on the basis of cerebral performance category (CPC) at 30 days post-CA. Logistic regression analysis was used to determine the association between serum glycocalyx markers and neurological outcomes. Patients were regrouped in light of 30-d mortality and Cox regression analysis was used to determine the association between serum glycocalyx markers and 30-d mortality. Results: A total of 71 patients were included in the study, including 31 (43.7%) females and 40 (56.3%) males, with an average age of (59.0±17.0) years. The poor function group (n=49) demonstrated significantly elevated levels of HS and HA when compared to the good function group (n=22) [HS: 2 461.0(1 623.0, 5 492.0) μg/L vs 1 492.0 (914.0, 2 550.0) μg/L, P=0.008; HA: 124.0(97.0, 365.0)μg/L vs 337.0(135.0, 1 421.0) μg/L, P=0.033]. Adjusted logistic regression analysis revealed that HS was independently associated with poor neurological outcome [odds ratio (OR)=0.389, 95% confidence interval (CI): 0.182-0.828, P=0.014]. In the 30-day mortality analysis, the death group (n=32) exhibited significantly higher levels of HS and HA when compared to the survival group (n=39) [HS: 1 880.0(1 011.0, 3 554.0) μg/L vs 2 500.0(1 726.0, 6 276.0) μg/L, P=0.027; HA: 162.0(99.0, 537.0) μg/L vs 813.0(148.0, 1 531.0) μg/L, P=0.025]. Adjusted Cox regression analysis indicated that elevated levels of HS and HA were independent risk factors (HS: HR=1.697, 95%CI: 1.126-2.557, P=0.011; HA: HR=1.336, 95%CI: 1.047-1.705, P=0.020) for 30-day mortality. Conclusions: High level of serum HS in 24 hours after CA may serve as a potential predictive marker for both neurological function and 30-day mortality. However, high level of serum HA appears to primarily predict 30-day mortality. Sdc-1 does not seem to contribute to outcome prediction.

Experimental study of modified Tavis-Cummings model with directly-coupled superconducting artificial atoms

The Tavis-Cummings model is intensively investigated in quantum optics and has important applications in generation of multi-atom entanglement. Here, we employ a superconducting circuit quantum electrodynamic system to study a modified Tavis-Cummings model with directly-coupled atoms. In our device, three superconducting artificial atoms are arranged in a chain with direct coupling through fixed capacitors and strongly coupled to a transmission line resonator. By performing transmission spectrum measurements, we observe different anticrossing structures when one or two qubits are resonantly coupled to the resonator. In the case of the two-qubit Tavis-Cummings model without qubit-qubit interaction, we observe two dips at the resonance point of the anticrossing. The splitting of these dips is determined by Δ λ=2g12+g32, where g1 and g3 are the coupling strengths between Qubit 1 and the resonator, and Qubit 3 and the resonator, respectively. The direct coupling J12 between the two qubits results in three dressed states in the two-qubit Tavis-Cummings model at the frequency resonance point, leading to three dips in the transmission spectrum. In this case, the distance between the two farthest and asymmetrical dips, arising from the energy level splitting, is larger than in the previous case. The frequency interval between these two dips is determined by the difference in eigenvalues (Δ λ=ε 1+-ε 1-), obtained through numerical calculations. What we believe as novel and intriguing experimental results may potentially advance quantum optics experiments, providing valuable insights for future research.

Downregulation of EZH2 inhibits epithelial-mesenchymal transition in enzalutamide-resistant prostate cancer

BACKGROUND

Androgen signaling inhibitors (ASI) have been approved for treatment of metastatic castration-resistant prostate cancer (mCRPC). However, the limited success of ASI in clinic justifies an urgent need to identify new targets and develop novel approaches for treatment. EZH2 significantly increases in prostate cancer (PCa). Little is understood, however, regarding the roles of EZH2 in Enzalutamide-resistant (EnzR) mCRPC.

METHODS

We firstly investigated the levels of EZH2 and the altered pathways in public database which was comprised with primary and metastatic PCa patient tumors. To elucidate the roles of EZH2 in mCRPC, we manipulated EZH2 in EnzR PCa cell lines to examine epithelial-mesenchymal transition (EMT). To dissect the underlying mechanisms, we measured the transcription levels of EMT-associated transcription factors (TFs).

RESULTS

We found that EZH2 was highly expressed in mCRPC than that of primary PCa tumors and that EnzR PCa cells gained more EMT characteristics than those of enzalutamide-sensitive counterparts. Further, loss of EZH2-induced inhibition of EMT is independent of polycomb repressive complex 2 (PRC2). Mechanistically, downregulation of EZH2 inhibits transcription of EMT-associated TFs by repressing formation of H3K4me3 to the promotor regions of the TFs.

CONCLUSION

We identified the novel roles of EZH2 in EnzR mCRPC. EnzR PCa gains more EMT properties than that of enzalutamide-sensitive PCa. Loss of EZH2-assocaited inhibition of EMT is PRC2 independent. Downregulation of EZH2 suppresses EMT by impairing formation of H3K4me3 at the promotor regions, thus repressing expression of EMT-associated TFs.

Phosphorylation of AHR by PLK1 promotes metastasis of LUAD via DIO2-TH signaling

Metastasis of lung adenocarcinoma (LUAD) is a major cause of death in patients. Aryl hydrocarbon receptor (AHR), an important transcription factor, is involved in the initiation and progression of lung cancer. Polo-like kinase 1 (PLK1), a serine/threonine kinase, acts as an oncogene promoting the malignancy of multiple cancer types. However, the interaction between these two factors and their significance in lung cancer remain to be determined. In this study, we demonstrate that PLK1 phosphorylates AHR at S489 in LUAD, leading to epithelial-mesenchymal transition (EMT) and metastatic events. RNA-seq analyses reveal that type 2 deiodinase (DIO2) is responsible for EMT and enhanced metastatic potential. DIO2 converts tetraiodothyronine (T4) to triiodothyronine (T3), activating thyroid hormone (TH) signaling. In vitro and in vivo experiments demonstrate that treatment with T3 or T4 promotes the metastasis of LUAD, whereas depletion of DIO2 or a deiodinase inhibitor disrupts this property. Taking together, our results identify the AHR phosphorylation by PLK1 and subsequent activation of DIO2-TH signaling as mechanisms leading to LUAD metastasis. These findings can inform possible therapeutic interventions for this event.

Single-cell analysis characterizes PLK1 as a catalyst of an immunosuppressive tumor microenvironment in LUAD

PLK1 (Polo-like kinase 1) plays a critical role in the progression of lung adenocarcinoma (LUAD). Recent studies have unveiled that targeting PLK1 improves the efficacy of immunotherapy, highlighting its important role in the regulation of tumor immunity. Nevertheless, our understanding of the intricate interplay between PLK1 and the tumor microenvironment (TME) remains incomplete. Here, using genetically engineered mouse model and single-cell RNA-seq analysis, we report that PLK1 promotes an immunosuppressive TME in LUAD, characterized with enhanced M2 polarization of tumor associated macrophages (TAM) and dampened antigen presentation process. Mechanistically, elevated PLK1 coincides with increased secretion of CXCL2 cytokine, which promotes M2 polarization of TAM and diminishes expression of class II major histocompatibility complex (MHC-II) in professional antigen-presenting cells. Furthermore, PLK1 negatively regulates MHC-II expression in cancer cells, which has been shown to be associated with compromised tumor immunity and unfavorable patient outcomes. Taken together, our results reveal PLK1 as a novel modulator of TME in LUAD and provide possible therapeutic interventions.

A multiline fitting method for measuring ethylene concentration based on WMS-2f/1f

Coal spontaneous combustion risk assessment is a global technical challenge for the sustainable development of deep mining technology, and C2H4 is a key indicator for early warning of coal spontaneous combustion. Tunable diode laser absorption spectroscopy (TDLAS) has the advantages of high selectivity, high sensitivity, high accuracy and real-time on-line measurement, and it can detect multiple gases simultaneously, so it has significant advantages in the accurate detection of coal spontaneous combustion indicator gases. To address the problem of cross-interference between the near-infrared absorption lines of CH4 and C2H4, which are the indicator gases of spontaneous combustion in coal, a multi-line fitting method was proposed in this study to calibrate the concentration of C2H4. The high-precision Environics2000 automatic standard gas dispenser from the United States, which has a built-in CPU computer control and data control and processing system, was used. Its gas concentration accuracy: ± 1.0%, gas flow accuracy: ± 1.0%, gas repeatability accuracy: ± 1.0%, flow linearity accuracy: ± 0.5%, and inlet operating pressure: minimum 10 psig (0.67 bar) ~ 75 psig (5.04 bar). The measured and simulated WMS-2f/1f signals were multilinearly fitted using a multilinear fitting algorithm and wavelength modulation spectroscopy (WMS), and the measurement of C2H4 concentration was achieved based on the extracted spectral line information. The results show that the maximum relative error of C2H4 concentration measurement is 2.40%, which is 54% lower than that of the conventional 2f peak measurement method, thus demonstrating the effectiveness of the multilinear fitting algorithm in the inversion of C2H4 concentration under the interference of absorption lines. In addition, this study has far-reaching implications for the application of TDLAS technology in the accurate detection of coal spontaneous combustion indicator gases.

Phosphorylation of AHR by PLK1 promotes metastasis of LUAD via DIO2-TH signaling

Metastasis of Lung adenocarcinoma (LUAD) is a major cause of death in patients. Aryl hydrocarbon receptor (AHR) is an important transcription factor involved in the initiation and progression of lung cancer. Polo-like kinase 1 (PLK1), a serine/threonine kinase, is an oncogene that promotes the malignancy of multiple cancer types. Nonetheless, the interaction between these two factors and significance in lung cancer remains to be determined. Here, we demonstrate that PLK1 phosphorylates AHR at S489 in LUAD, which leads to epithelial-mesenchymal transition (EMT) and metastatic events. RNA-seq analyses show that type 2 deiodinase (DIO2) is responsible for EMT and enhanced metastatic potential. DIO2 converts tetraiodothyronine (T4) to triiodothyronine (T3), which then activates thyroid hormone signaling. In vitro and in vivo experiments demonstrate that treatment with T3 or T4 promotes the metastasis of LUAD, whereas depletion of DIO2 or deiodinase inhibitor disrupts this property. Taken together, our results identify the phosphorylation of AHR by PLK1 as a mechanism leading to the progression of LUAD and provide possible therapeutic interventions for this event.

The PLOD2/succinate axis regulates the epithelial-mesenchymal plasticity and cancer cell stemness

Aberrant accumulation of succinate has been detected in many cancers. However, the cellular function and regulation of succinate in cancer progression is not completely understood. Using stable isotope-resolved metabolomics analysis, we showed that the epithelial mesenchymal transition (EMT) was associated with profound changes in metabolites, including elevation of cytoplasmic succinate levels. The treatment with cell-permeable succinate induced mesenchymal phenotypes in mammary epithelial cells and enhanced cancer cell stemness. Chromatin immunoprecipitation and sequence analysis showed that elevated cytoplasmic succinate levels were sufficient to reduce global 5-hydroxymethylcytosinene (5hmC) accumulation and induce transcriptional repression of EMT-related genes. We showed that expression of procollagen-lysine,2-oxoglutarate 5-dioxygenase 2 (PLOD2) was associated with elevation of cytoplasmic succinate during the EMT process. Silencing of PLOD2 expression in breast cancer cells reduced succinate levels and inhibited cancer cell mesenchymal phenotypes and stemness, which was accompanied by elevated 5hmC levels in chromatin. Importantly, exogenous succinate rescued cancer cell stemness and 5hmC levels in PLOD2-silenced cells, suggesting that PLOD2 promotes cancer progression at least partially through succinate. These results reveal the previously unidentified function of succinate in enhancing cancer cell plasticity and stemness.

A kinome-wide CRISPR screen identifies CK1α as a target to overcome enzalutamide resistance of prostate cancer

Enzalutamide (ENZA), a second-generation androgen receptor antagonist, has significantly increased progression-free and overall survival of patients with metastatic prostate cancer (PCa). However, resistance remains a prominent obstacle in treatment. Utilizing a kinome-wide CRISPR-Cas9 knockout screen, we identified casein kinase 1α (CK1α) as a therapeutic target to overcome ENZA resistance. Depletion or pharmacologic inhibition of CK1α enhanced ENZA efficacy in ENZA-resistant cells and patient-derived xenografts. Mechanistically, CK1α phosphorylates the serine residue S1270 and modulates the protein abundance of ataxia telangiectasia mutated (ATM), a primary initiator of DNA double-strand break (DSB)-response signaling, which is compromised in ENZA-resistant cells and patients. Inhibition of CK1α stabilizes ATM, resulting in the restoration of DSB signaling, and thus increases ENZA-induced cell death and growth arrest. Our study details a therapeutic approach for ENZA-resistant PCa and characterizes a particular perspective for the function of CK1α in the regulation of DNA-damage response.

Abstract 2581: Fatty acid synthase regulates expression of Notum in colorectal cancer

Background: Upregulation of lipid synthesis has been associated with poor clinical outcomes in colorectal cancer (CRC). Fatty acid synthase (FASN) synthesizes 16-carbon fatty acid palmitate which can be utilized for post-translational modifications of various proteins. Notum, a palmitoleoyl-protein carboxylesterase, is involved in the negative regulation of the Wnt signaling via its role in de-palmitoylation of Wnt ligands and has been identified as a marker for poor prognosis in CRC. However, the crosstalk between FASN and Notum has not been reported. Our preliminary data suggest that FASN regulates β-catenin signaling and Notum expression. Therefore, the purpose of this study is to elucidate (I) the mechanisms of how FASN regulates expression of Notum and (II) the contribution of the FASN/Notum axis to CRC.

Methods: Tumor and normal intestinal organoids were established from transgenic mice models, ApcMin and Apc/VillinCre-ERT2, with inducible hetero- and homozygous deletion of FASN. The effect of genetic deletion and pharmacological inhibition of FASN on organoid growth and viability was assessed by 4-hydroxytamoxifen (4-OHT) and TVB-3664 (a FASN inhibitor) treatments, respectively. LIVE/DEAD™ Viability/Cytotoxicity Cell Viability Kit and Cell Titer-Glo® 3D Cell Viability Assays were used for quantitative analysis of growth and viability. HCT116, NTC and FASN shRNA, and SW480, control and FASN overexpression, cells were used for analysis.

Results: ERT2-mediated deletion of Apc leads to upregulation of FASN and Notum expression in mouse intestinal tissues and organoids. RNA-seq analysis of adenomas from Apc/VillinCre mice showed that hetero- and homozygous germline deletion of FASN is associated with a significant decrease in the number of adenomas, expression of Notum and CRC stem cell markers. Using qRT-PCR and Western blot, we confirmed that FASN downregulation is associated with a decrease in active β-catenin, Notum, and stem cell markers. Consistently with Apc/VillinCre model, downregulation of FASN results in a decrease in bud formation in Apc/VillinCre-ERT2 organoids, and viability and size in ApcMin organoids. Furthermore, overexpression of FASN increases the levels of active and total β-catenin, Notum, and stem cell markers expression in SW480 cells. In contrast, shRNA-mediated deletion of FASN decreases expression of Notum in HCT116 cells.

Conclusion: Downregulation of FASN leads to a decrease in expression of Notum and is associated with morphological changes and a significant decrease in viability in organoid models. Conversely, FASN overexpression upregulates Notum expression suggesting a potential cross-talk between de novo lipid synthesis and Notum. Delineating the role of FASN regulation of stemness via altered β-catenin signaling and expression of Notum and other stem cell markers will provide the rationale for targeting the FASN/Notum axis as a preventative or early-stage therapeutic approach in CRC.

Citation Format: Courtney Olivia Kelson, James Drury, Daheng He, Chi Wang, Yekaterina Zaytseva. Fatty acid synthase regulates expression of Notum in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2581.

Abstract 295: Targeting spermine synthase triggers lipid metabolism reprogramming as a new therapeutic option to combat colorectal cancer

Dysregulation of polyamine metabolism has been linked to the development of colorectal cancer (CRC). Our recent work demonstrates that spermine synthase (SMS), a polyamine biosynthetic enzyme that converts spermidine to spermine, is overexpressed in CRC, which is required for balancing cellular spermidine levels to facilitate CRC tumorigenesis (Nat Commun 11:3243, 2020). Our findings reveal SMS as an attractive therapeutic target in CRC; yet, genetic depletion of SMS expression only shows a limited antitumor effect. Using unbiased metabolomics and transcriptomics analyses, we identified a lipid metabolism reprograming as among the most impacted metabolic change by SMS depletion in CRC cells. Specifically, SMS depletion significantly altered long-chain fatty acid, triacylglycerol and phospholipid metabolism. Furthermore, targeted inhibition of SMS significantly increased the number of lipid droplets and the levels of long-chain fatty acid acylcarnitines for oxidative phosphorylation in mitochondria, and upregulated expression of genes associated with increased mobilization of polyunsaturated fatty acids and the genes associated with lipid peroxidation for induction of ferroptosis, an iron-dependent form of nonapoptotic cell death. The glutathione peroxidase 4 (GPX4) is a key negative regulator of ferroptosis by neutralizing lipid peroxides. Notably, pharmacological inhibition of GPX4 or its upstream regulator system xc − in combination with genetic depletion or pharmacologic inhibition of SMS synergistically caused lipid peroxidation leading to ferroptosis induction and marked suppression of CRC cell growth. Collectively, these findings highlight lipid metabolism reprograming as an adaptive response to targeted inhibition of SMS to enable CRC cell survival, which represents an Achilles’ heel that can be exploited for potential effective therapy for CRC.

Citation Format: Murong Ma, Yubin Guo, Qing Ye, Pan Deng, Daheng He, Chi Wang, Qing-Bai She. Targeting spermine synthase triggers lipid metabolism reprogramming as a new therapeutic option to combat colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 295.

Latexin regulates sex dimorphism in hematopoiesis via gender-specific differential expression of microRNA 98-3p and thrombospondin 1

Hematopoietic stem cells (HSCs) have the ability to self-renew and differentiate to all blood cell types. HSCs and their differentiated progeny show sex/gender differences. The fundamental mechanisms remain largely unexplored. We previously reported that latexin (Lxn) deletion increased HSC survival and repopulation capacity in female mice. Here, we find no differences in HSC function and hematopoiesis in Lxn knockout (Lxn-/-) male mice under physiologic and myelosuppressive conditions. We further find that Thbs1, a downstream target gene of Lxn in female HSCs, is repressed in male HSCs. Male-specific high expression of microRNA 98-3p (miR98-3p) contributes to Thbs1 suppression in male HSCs, thus abrogating the functional effect of Lxn in male HSCs and hematopoiesis. These findings uncover a regulatory mechanism involving a sex-chromosome-related microRNA and its differential control of Lxn-Thbs1 signaling in hematopoiesis and shed light on the process underlying sex dimorphism in both normal and malignant hematopoiesis.

Exome-wide screening identifies novel rare risk variants for bone mineral density

Bone mineral density (BMD) is an independent risk factor of osteoporosis-related fractures. We performed gene-based burden tests to assess the association between rare variants and BMD, and identified several BMD candidate genes.

PURPOSE

BMD is highly heritable and a major predictor of osteoporotic fractures, but its genetic basis remains unclear. We aimed to identify rare risk variants contributing to BMD.

METHODS

Utilizing the newly released UK Biobank 200,643 exome dataset, we conducted a gene-based exome-wide association study in males and females, respectively. First, 100,639 males and 117,338 females with BMD values were included in the polygenic risk scores (PRS) analysis. Among individuals with lower 30% PRS, cases were individuals with top 10% BMD, and individuals with bottom 10% BMD were the controls. Considering the effects of vitamin D (VD), individuals with the highest 30% VD concentration were selected for VD-BMD analysis. After quality control, 741 males and 697 females were included in the BMD analysis, and 717 males and 708 females were included in the VD-BMD analysis. The variants were annotated by ANNOVAR software, then BMD and VD-BMD qualified variants were imported into the SKAT R-package to perform gene-based burden tests, respectively.

RESULTS

The gene-based burden test of the exonic variants identified genome-wide candidate associations in ANKRD18A (P = 1.60 × 10^-5, P_{Bonferroni adjust} = 2.11 × 10^-3), C22orf31 (P = 3.49 × 10^-4, P_{Bonferroni adjust} = 3.17 × 10^-2), and SPATC1L (P = 1.09 × 10^-5, P_{Bonferroni adjust} = 8.80 × 10^-3). For VD-BMD analysis, three genes were associated with BMD, such as NIPAL1 (P = 1.06 × 10^-3, P_{Bonferroni adjust} = 3.91 × 10^-2).

CONCLUSIONS

Our study suggested that rare variants contribute to BMD, providing new sights for broadening the genetic structure of BMD.

ABL1/2 and DDR1 Drive MEKi Resistance in NRAS-Mutant Melanomas by Stabilizing RAF/MYC/ETS1 and Promoting RAF Homodimerization

Melanomas harboring NRAS mutations are a particularly aggressive and deadly subtype. If patients cannot tolerate or the melanomas are insensitive to immune checkpoint blockade, there are no effective 2nd-line treatment options. Drugs targeting the RAF/MEK/ERK pathway, which are used for BRAF-mutant melanomas, do little to increase progression-free survival (PFS). Here, using both loss-of-function and gain-of-function approaches, we show that ABL1/2 and DDR1 are critical nodes during NRAS-mutant melanoma intrinsic and acquired MEK inhibitor (MEKi) resistance. In some acquired resistance cells, ABL1/2 and DDR1 cooperate to stabilize RAF proteins, activate ERK cytoplasmic and nuclear signaling, repress p27/KIP1 expression, and drive RAF homodimerization. In contrast, other acquired resistance cells depend solely on ABL1/2 for their survival, and are sensitive to highly specific allosteric ABL1/2 inhibitors, which prevent β-catenin nuclear localization and destabilize MYC and ETS1 in an ERK-independent manner. Significantly, targeting ABL1/2 and DDR1 with an FDA-approved anti-leukemic drug, reverses intrinsic MEKi resistance, delays acquisition of acquired resistance, and doubles the survival time in a NRAS-mutant mouse model. These data indicate that repurposing FDA-approved drugs targeting ABL1/2 and DDR1 may be a novel and effective strategy for treating patients with treatment-refractory NRAS-driven melanomas.

Targeting Plk1 Sensitizes Pancreatic Cancer to Immune Checkpoint Therapy

Polo-like kinase 1 (Plk1) plays an important role in cell-cycle regulation. Recent work has suggested that Plk1 could be a biomarker of gemcitabine response in pancreatic ductal adenocarcinoma (PDAC). Although targeting Plk1 to treat PDAC has been attempted in clinical trials, the results were not promising, and the mechanisms of resistance to Plk1 inhibition is poorly understood. In addition, the role of Plk1 in PDAC progression requires further elucidation. Here, we showed that Plk1 was associated with poor outcomes in patients with PDAC. In an inducible transgenic mouse line with specific expression of Plk1 in the pancreas, Plk1 overexpression significantly inhibited caerulein-induced acute pancreatitis and delayed development of acinar-to-ductal metaplasia and pancreatic intraepithelial neoplasia. Bioinformatics analyses identified the regulatory networks in which Plk1 is involved in PDAC disease progression, including multiple inflammation-related pathways. Unexpectedly, inhibition or depletion of Plk1 resulted in upregulation of PD-L1 via activation of the NF-κB pathway. Mechanistically, Plk1-mediated phosphorylation of RB at S758 inhibited the translocation of NF-κB to nucleus, inactivating the pathway. Inhibition of Plk1 sensitized PDAC to immune checkpoint blockade therapy through activation of an antitumor immune response. Together, Plk1 suppresses PDAC progression and inhibits NF-κB activity, and targeting Plk1 can potentiate the efficacy of immunotherapy in PDAC.

SIGNIFICANCE

Inhibition of Plk1 induces upregulation of PD-L1 expression in pancreatic ductal adenocarcinoma, stimulating antitumor immunity and sensitizing tumors to immunotherapy.

The kinase PLK1 promotes the development of <i>Kras</i>/<i>Tp53</i>-mutant lung adenocarcinoma through transcriptional activation of the receptor RET

Increased abundance of polo-like kinase 1 (PLK1) is observed in various tumor types, particularly in lung adenocarcinoma (LUAD). Here, we found that PLK1 accelerated the progression of LUAD through a mechanism that was independent of its role in mediating mitotic cell division. Analysis of human tumor databases revealed that increased PLK1 abundance in LUAD correlated with mutations in KRAS and p53, with tumor stage, and with reduced survival in patients. In a mouse model of KRAS^G12D-driven, p53-deficient LUAD, PLK1 overexpression increased tumor burden, decreased tumor cell differentiation, and reduced animal survival. PLK1 overexpression in cultured cells and mice indirectly increased the expression of the gene encoding the receptor tyrosine kinase RET by phosphorylating the transcription factor TTF-1. Signaling by RET and mutant KRAS in these tumors converged to activate the mitogen-activated protein kinase (MAPK) pathway. Pharmacological inhibition of the MAPK pathway kinase MEK combined with inhibition of either RET or PLK1 markedly suppressed tumor growth. Our findings show that PLK1 can amplify MAPK signaling and reveal a potential target for stemming progression in lung cancers with high PLK1 abundance.

GSTM2 is a key molecular determinant of resistance to SG-ARIs

Prostate cancer (PCa) continues to threaten men's health, and treatment targeting the androgen receptor (AR) pathway is the major therapy for PCa patients. Several second-generation androgen receptor inhibitors (SG-ARIs), including enzalutamide (ENZ), apalutamide (APA) and darolutamide (DARO), have been developed to better block the activity of AR. Unavoidably, emergence of resistance to these novel drugs still persists. Herein, we identified glutathione S-transferase Mu 2 (GSTM2) as an important determinant in the acquisition of resistance to SG-ARIs. Elevated GSTM2 was detected in enzalutamide-resistant (ENZ-R) PCa, and overexpression of GSTM2 in naïve enzalutamide-sensitive (ENZ-S) cells effectively transformed them to ENZ-R PCa. Aryl hydrocarbon receptor (AhR), the upstream transcription factor, was implicated in the overexpression of GSTM2 in ENZ-R cells. Mechanistically, GSTM2 antagonized the effect of ENZ by rescuing cells from oxidative stress-associated damage and activation of p38 MAPK pathway. Surprisingly, high GSTM2 levels also associated with cross-resistance to APA and DARO. Taking together, these results provide new insight to ameliorate resistance to SG-ARIs and improve treatment outcome.

The RelB-BLNK Axis Determines Cellular Response to a Novel Redox-Active Agent Betamethasone during Radiation Therapy in Prostate Cancer

Aberrant levels of reactive oxygen species (ROS) are potential mechanisms that contribute to both cancer therapy efficacy and the side effects of cancer treatment. Upregulation of the non-canonical redox-sensitive NF-kB family member, RelB, confers radioresistance in prostate cancer (PCa). We screened FDA-approved compounds and identified betamethasone (BET) as a drug that increases hydrogen peroxide levels in vitro and protects non-PCa tissues/cells while also enhancing radiation killing of PCa tissues/cells, both in vitro and in vivo. Significantly, BET increases ROS levels and exerts different effects on RelB expression in normal cells and PCa cells. BET induces protein expression of RelB and RelB target genes, including the primary antioxidant enzyme, manganese superoxide dismutase (MnSOD), in normal cells, while it suppresses protein expression of RelB and MnSOD in LNCaP cells and PC3 cells. RNA sequencing analysis identifies B-cell linker protein (BLNK) as a novel RelB complementary partner that BET differentially regulates in normal cells and PCa cells. RelB and BLNK are upregulated and correlate with the aggressiveness of PCa in human samples. The RelB-BLNK axis translocates to the nuclear compartment to activate MnSOD protein expression. BET promotes the RelB-BLNK axis in normal cells but suppresses the RelB-BLNK axis in PCa cells. Targeted disruptions of RelB-BLNK expressions mitigate the radioprotective effect of BET on normal cells and the radiosensitizing effect of BET on PCa cells. Our study identified a novel RelB complementary partner and reveals a complex redox-mediated mechanism showing that the RelB-BLNK axis, at least in part, triggers differential responses to the redox-active agent BET by stimulating adaptive responses in normal cells but pushing PCa cells into oxidative stress overload.

Tumor Suppressor Par-4 Regulates Complement Factor C3 and Obesity

Prostate apoptosis response-4 (Par-4) is a tumor suppressor that induces apoptosis in cancer cells. However, the physiological function of Par-4 remains unknown. Here we show that conventional Par-4 knockout (Par-4^-/-) mice and adipocyte-specific Par-4 knockout (AKO) mice, but not hepatocyte-specific Par-4 knockout mice, are obese with standard chow diet. Par-4^-/- and AKO mice exhibit increased absorption and storage of fat in adipocytes. Mechanistically, Par-4 loss is associated with mdm2 downregulation and activation of p53. We identified complement factor c3 as a p53-regulated gene linked to fat storage in adipocytes. Par-4 re-expression in adipocytes or c3 deletion reversed the obese mouse phenotype. Moreover, obese human subjects showed lower expression of Par-4 relative to lean subjects, and in longitudinal studies, low baseline Par-4 levels denoted an increased risk of developing obesity later in life. These findings indicate that Par-4 suppresses p53 and its target c3 to regulate obesity.

Development and validation of an individualized nomogram for predicting the high-volume (> 5) central lymph node metastasis in papillary thyroid microcarcinoma

PURPOSE

Papillary thyroid microcarcinoma (PTMC) frequently presents a favorable clinical outcome, while aggressive invasiveness can also be found in some of this population. Identifying the risk clinical factors of high-volume (> 5) central lymph node metastasis (CLNM) in PTMC patients could help oncologists make a better-individualized clinical decision.

METHODS

We retrospectively reviewed the clinical characteristics of adult patients with PTC in the Surveillance, Epidemiology, and End Results (SEER) database between Jan 2010 and Dec 2015 and in one medical center affiliated to Chongqing Medical University between Jan 2018 and Oct 2020. Univariate and multivariate logistic regression analyses were used to determine the risk factors for high volume of CLNM in PTMC patients.

RESULTS

The male gender (OR = 2.02, 95% CI 1.46-2.81), larger tumor size (> 5 mm, OR = 1.64, 95% CI 1.13-2.38), multifocality (OR = 1.87, 95% CI 1.40-2.51), and extrathyroidal invasion (OR = 3.67; 95% CI 2.64-5.10) were independent risk factors in promoting high-volume of CLNM in PTMC patients. By contrast, elderly age (≥ 55 years) at diagnosis (OR = 0.57, 95% CI 0.40-0.81) and PTMC-follicular variate (OR = 0.60, 95% CI 0.42-0.87) were determined as the protective factors. Based on these indicators, a nomogram was further constructed with a good concordance index (C-index) of 0.702, supported by an external validating cohort with a promising C-index of 0.811.

CONCLUSION

A nomogram was successfully established and validated with six clinical indicators. This model could help surgeons to make a better-individualized clinical decision on the management of PTMC patients, especially in terms of whether prophylactic central lymph node dissection and postoperative radiotherapy should be warranted.

[Study on parameters of robot-assisted ultrasonic drilling on bovine vertebral body]

Objective: To investigate the effect of ultrasonic parameter settings on maximum temperatures in the drilling site and penetration time and determine the most suitable parameters for efficient and safe robot-based ultrasonic bone drilling in spinal surgery. Methods: Five adult bovine thoracic and lumbar vertebrae specimens (T10-L6) were cut into 10 mm thick slices. A total of 50 slices were obtained. Among them, 30 and 20 slices were used for cancellous bone experiments and cortical bone experiments, respectively. In the cancellous bone experiment, the slices were randomly divided into three groups, corresponding to different feed rates of 0.8 mm/s, 1.6 mm/s, and 2.4 mm/s, respectively, with 10 slices in each group. The cancellous part of each slice was drilled 9 times with different output powers from 20% (48 W) to 100% (120 W). In the cortical bone experiment, the slices were randomly assigned into two groups, corresponding to a different feed rate (0.8 mm/s and 1.6 mm/s). Drilling was performed on the cortical part of each slice 4 times with different output power, which increased from 70% (84W) to 100% (120 W). All experiments were conducted at room temperature of 25 ℃. Maximum temperature and penetration time were recorded. The maximum grinding temperature and penetration time of cancellous bone and cortical bone under different output power and feed rate were compared. Results: At the same feed rate, the maximum temperature of the cancellous bone decreased as output power increased. There were statistically significant differences in the maximum temperature between the output powers of 120 W and 24 W under different feed rates(61.2 ℃±9.4 ℃ vs 70.9 ℃±5.7 ℃, 59.2 ℃±7.1 ℃ vs 69.5 ℃±10.7 ℃, 55.5 ℃±5.5 ℃ vs 69.2 ℃±9.3 ℃, all P<0.05). At the premise of the same output power, there was no significant difference in the maximum temperature among different feed rates (all P>0.05). At the feed rate of 0.8 mm/s, the maximum temperature of cortical bone decreased as the output power increased. The maximum temperature at the output power of 120 W was significantly lower than that of 84 W (P=0.048). However, at the feed rate of 1.6 mm/s, the maximum temperature could not be significantly lowered by the increase in output power (P>0.05). Under the same output power, the maximum temperature at the feed rate of 1.6 mm/s were all significantly lower than those of 0.8 mm/s (all P<0.05). The penetration time of cancellous bone did not decrease significantly with the increase in the output power (all P>0.05) while it decreased significantly as the feed rate increased (all P<0.05). Regarding cortical bone at the feed rate of 0.8 mm/s, the increase in output power could not shorten the penetration time (P>0.05); at the feed rate of 1.6 mm/s, the penetration time at the output power of 120 W was significantly shorter than that of 96 W (P=0.008). With the same output power, the penetration time at the feed rate of 1.6 mm/s were significantly shorter than those at 0.8 mm/s (all P<0.05). There was no statistical difference in the penetration failure rate among different feed rates with the same output power (all P>0.05). The penetration failure rate was 0 when the output power of cancellous bone was 48 W and above and the output power of cortical bone were 108 W and 120 W. Conclusions: The maximum temperature of vertebral cancellous bone and the cortical bone is primarily influenced by the output power and the feed rate, respectively; the penetration time of cancellous bone and the cortical bone is affected by the feed rate and both of feed rate and output power, respectively. The most suitable parameters are output power of 120 W and feed rate of 2.4 mm/s for cancellous bone and output power of 120 W and feed rate of 1.6 mm/s for cortical bone.

Upregulation of CD36, a Fatty Acid Translocase, Promotes Colorectal Cancer Metastasis by Increasing MMP28 and Decreasing E-Cadherin Expression

Altered fatty acid metabolism continues to be an attractive target for therapeutic intervention in cancer. We previously found that colorectal cancer (CRC) cells with a higher metastatic potential express a higher level of fatty acid translocase (CD36). However, the role of CD36 in CRC metastasis has not been studied. Here, we demonstrate that high expression of CD36 promotes invasion of CRC cells. Consistently, CD36 promoted lung metastasis in the tail vein model and GI metastasis in the cecum injection model. RNA-Seq analysis of CRC cells with altered expression of CD36 revealed an association between high expression of CD36 and upregulation of MMP28, a novel member of the metallopeptidase family of proteins. Using shRNA-mediated knockdown and overexpression of CD36, we confirmed that CD36 regulates MMP28 expression in CRC cells. siRNA-mediated knockdown of MMP28 decreases invasion of CRC cells, suggesting that MMP28 regulates the metastatic properties of cells downstream of CD36. Importantly, high expression of MMP28 leads to a significant decrease in active E-cadherin and an increase in the products of E-cadherin cleavage, CTF1 and CTF2. In summary, upregulation of CD36 expression promotes the metastatic properties of CRC via upregulation of MMP28 and an increase in E-cadherin cleavage, suggesting that targeting the CD36-MMP28 axis may be an effective therapeutic strategy for CRC metastasis.

Potent Synergistic Effect on C-Myc-Driven Colorectal Cancers Using a Novel Indole-Substituted Quinoline with a Plk1 Inhibitor

Developing effective treatments for colorectal cancers through combinations of small-molecule approaches and immunotherapies present intriguing possibilities for managing these otherwise intractable cancers. During a broad-based, screening effort against multiple colorectal cancer cell lines, we identified indole-substituted quinolines (ISQ), such as N7,N7 -dimethyl-3-(1-methyl-1H-indol-3-yl)quinoline-2,7-diamine (ISQ-1), as potent in vitro inhibitors of several cancer cell lines. We found that ISQ-1 inhibited Wnt signaling, a main driver in the pathway governing colorectal cancer development, and ISQ-1 also activated adenosine monophosphate kinase (AMPK), a cellular energy-homeostasis master regulator. We explored the effect of ISQs on cell metabolism. Seahorse assays measuring oxygen consumption rate (OCR) indicated that ISQ-1 inhibited complex I (i.e., NADH ubiquinone oxidoreductase) in the mitochondrial, electron transport chain (ETC). In addition, ISQ-1 treatment showed remarkable synergistic depletion of oncogenic c-Myc protein level in vitro and induced strong tumor remission in vivo when administered together with BI2536, a polo-like kinase-1 (Plk1) inhibitor. These studies point toward the potential value of dual drug therapies targeting the ETC and Plk-1 for the treatment of c-Myc-driven cancers.

[Proximal incisal edge length and recent clinical observation of Siewert type Ⅱ advanced esophagogastric junction adenocarcinoma]

Objective: To investigate the clinical effect of the radical resection with a proximal incisal edge length of 20-25 mm and 30-35 mm in Siewert type Ⅱ advanced esophagogastric junction adenocarcinoma, to shorten the minimum safe distance of the proximal incisal edge to 20-25 mm. Methods: A retrospective cohort study method was used. The clinical data of 166 patients with Siewert type Ⅱ advanced esophagogastric junction adenocarcinoma who underwent total gastrectomy from January 2017 to August 2020 in the Department of Gastrointestinal Surgery, Heji Hospital Affiliated to Changzhi Medical College were retrospectively collected. According to the proximal incisal edge length, the patients were divided into two groups: the proximal incisal edge length of 20-25 mm group (69 cases) and 30-35 mm group (97 cases). The perioperative conditions and the 6-month follow-up after the operation were compared between the two groups. Results: There was no statistically significant difference in baseline information between the patients in the two groups (P>0.05). The operations of both groups were completed. The intraoperative operation time of the proximal incisal edge length of 20-25 mm group was shorter than that in the proximal incisal edge length of 30-35 mm group ((172±24)and(206±27)min, P<0.001). There were no significant differences in the amount of intraoperative blood loss, the treatment of the diaphragm during the operation and the positive rate of intraoperative freezing of the upper incisal edge between the patients in the two groups (all P>0.05). And there was no significant differences in the first exhaust time, gastric tube removal time, first feeding time and hospital stay after the operation of the two groups (all P>0.05). There was no significant differences in the incidence of anastomotic leakage, anastomotic stenosis, reflux esophagitis and intestinal obstruction after the operation between the patients in the two groups (all P>0.05). And there was no anastomotic leakage case among the 69 cases in the proximal incisal edge length of 20-25 mm group. Postoperative pathological treatment showed no significant differences in the vascular tumor thrombus and nerve infiltration between the two groups (both P>0.05). During the 6-month follow-up, there was no death or tumor recurrence in the two groups, and there was no significant difference in body weight loss at 6 months after the operation between the two groups (P=0.178). Conclusion: When radical resection of Siewert type Ⅱ advanced esophagogastric junction adenocarcinoma is performed, it is feasible to shorten the minimum safe distance of the proximal incisal edge to 20-25 mm under the premise of ensuring R0 resection. The operation time is shortened. Due to the shortening the incisal edge distance, the anastomotic tension is decreased, and the incidence of postoperative anastomotic leakage is also reduced.

Exogenous trehalose protects photosystem II by promoting cyclic electron flow under heat and drought stresses in winter wheat

Drought and rising global temperatures are important factors that reduce wheat production. Trehalose protects the reaction centres and improves photosystem II (PSII) activity under diverse stress conditions. However, the underlying mechanism remains unknown. Cyclic electron flow (CEF) plays an important role in protecting PSII under environmental stresses. Our study focused on the effects of exogenous trehalose on the activity of PSII, D1 protein content, plastoquinone (PQ) pool and ATP synthase activity in wheat seedlings under heat and drought stresses to explore the relationship between trehalose and CEF. The results indicated that heat and drought stresses decreased maximum photochemical efficiency of PSII (F_v /F_m ) and electron transport rate of PSII (EFR(II)), whereas the trehalose pretreatment improved photochemical efficiency and electron transport rate of PSII. The trehalose pretreatment stimulated CEF under heat and drought stresses. Furthermore, the proton gradient (ΔpH) across the thylakoid membrane and ATPase activity increased. The higher ΔpH and ATPase activity played a key role in protecting PSII under stresses. Trehalose pretreatment could reduce inhibition caused by heat and drought stresses on the PQ pool. Thus, our results indicated that photoinhibition in heat- and drought-stressed plants was alleviated by the trehalose pretreatment, which was mediated by CEF and the PQ pool.

Innate immune activation by checkpoint inhibition in human patient-derived lung cancer tissues

Although Pembrolizumab-based immunotherapy has significantly improved lung cancer patient survival, many patients show variable efficacy and resistance development. A better understanding of the drug’s action is needed to improve patient outcomes. Functional heterogeneity of the tumor microenvironment (TME) is crucial to modulating drug resistance; understanding of individual patients’ TME that impacts drug response is hampered by lack of appropriate models. Lung organotypic tissue slice cultures (OTC) with patients’ native TME procured from primary and brain-metastasized (BM) non-small cell lung cancer (NSCLC) patients were treated with Pembrolizumab and/or beta-glucan (WGP, an innate immune activator). Metabolic tracing with ¹³C₆-Glc/¹³C₅,¹⁵N₂-Gln, multiplex immunofluorescence, and digital spatial profiling (DSP) were employed to interrogate metabolic and functional responses to Pembrolizumab and/or WGP. Primary and BM PD-1⁺ lung cancer OTC responded to Pembrolizumab and Pembrolizumab + WGP treatments, respectively. Pembrolizumab activated innate immune metabolism and functions in primary OTC, which were accompanied by tissue damage. DSP analysis indicated an overall decrease in immunosuppressive macrophages and T cells but revealed microheterogeneity in immune responses and tissue damage. Two TMEs with altered cancer cell properties showed resistance. Pembrolizumab or WGP alone had negligible effects on BM-lung cancer OTC but Pembrolizumab + WGP blocked central metabolism with increased pro-inflammatory effector release and tissue damage. In-depth metabolic analysis and multiplex TME imaging of lung cancer OTC demonstrated overall innate immune activation by Pembrolizumab but heterogeneous responses in the native TME of a patient with primary NSCLC. Metabolic and functional analysis also revealed synergistic action of Pembrolizumab and WGP in OTC of metastatic NSCLC.

Co-Targeting Plk1 and DNMT3a in Advanced Prostate Cancer

Because there is no effective treatment for late-stage prostate cancer (PCa) at this moment, identifying novel targets for therapy of advanced PCa is urgently needed. A new network-based systems biology approach, XDeath, is developed to detect crosstalk of signaling pathways associated with PCa progression. This unique integrated network merges gene causal regulation networks and protein-protein interactions to identify novel co-targets for PCa treatment. The results show that polo-like kinase 1 (Plk1) and DNA methyltransferase 3A (DNMT3a)-related signaling pathways are robustly enhanced during PCa progression and together they regulate autophagy as a common death mode. Mechanistically, it is shown that Plk1 phosphorylation of DNMT3a leads to its degradation in mitosis and that DNMT3a represses Plk1 transcription to inhibit autophagy in interphase, suggesting a negative feedback loop between these two proteins. Finally, a combination of the DNMT inhibitor 5-Aza-2'-deoxycytidine (5-Aza) with inhibition of Plk1 suppresses PCa synergistically.

Reactive-oxygen-species-scavenging nanomaterials for resolving inflammation

Reactive oxygen species (ROS) mediate multiple physiological functions; however, the over-accumulation of ROS causes premature aging and/or death and is associated with various inflammatory conditions. Nevertheless, there are limited clinical treatment options that are currently available. The good news is that owing to the considerable advances in nanoscience, multiple types of nanomaterials with unique ROS-scavenging abilities that influence the temporospatial dynamic behaviors of ROS in biological systems have been developed. This has led to the emergence of next-generation nanomaterial-controlled strategies aimed at ameliorating ROS-related inflammatory conditions. Accordingly, herein we reviewed recent progress in research on nanotherapy based on ROS scavenging. The underlying mechanisms of the employed nanomaterials are emphasized. Furthermore, important issues in developing cross-disciplinary nanomedicine-based strategies for ROS-based inflammatory conditions are discussed. Our review of this increasing interdisciplinary field will benefit ongoing studies and clinical applications of nanomedicine based on ROS scavenging.

POS0664 A MULTICENTER RANDOMIZED STUDY IN RHEUMATOID ARTHRITIS TO COMPARE IGURATIMOD, METHOTREXATE, OR COMBINATION: 52 WEEK EFFICACY AND SAFETY RESULTS OF THE SMILE TRIAL

Background:

Iguratimod (IGU) has demonstrated efficacy and safety for active rheumatoid arthritis (RA) patients in double-blind clinical trials in China and Japan as a new disease-modifying anti-rheumatic drug (DMARD). There are no studies evaluating the radiographic progression of structural joint damage of IGU for the treatment of RA using the mTSS as the primary endpoint.

Objectives:

Our study was to evaluate the efficacy and safety of IGU monotherapy and IGU combined methotrexate (MTX) compared with MTX monotherapy, including the inhibitory effects of joint destruction.

Methods:

This randomized, double-blind, parallel-controlled, multicenter study in patients with active RA who have not previously used MTX and biological DMARDs (bDMARDs) (ClinicalTrials.gov Identifier NCT01548001) was carried out in China. Patients were randomized 1:1:1 to receive IGU 25 mg twice a day (bid), MTX 10mg once a week(qw) for the first 4 weeks and 15 mg once a week(qw) for week 5 to 52, or IGU combined MTX (IGU+MTX) for 52 weeks. The primary endpoints were to assess and compare American College of Rheumatology 20% (ACR20) response and the change of modified total Sharp scoring (mTSS) score over 52 weeks (Intention-to-treat, ITT analysis). The non-inferiority test was used to analyze the difference of ACR20 response at 52 weeks between the IGU monotherapy and the MTX monotherapy arms, and the non-inferiority limit value was 10%. The difference test was used for the comparison between the IGU+MTX and MTX monotherapy arms. Two-way ANOVA was used to analyze the difference of the changes of mTSS score of each arm compared with baseline value (0 week).

Results:

A total of 895 patients were randomized to IGU 25mg bid (n =297), MTX 10-15mg qw(n=293), and IGU+MTX (n=305). Baseline characteristics were comparable between the arms (Table 1).

Table 1.

Demographic and Other Baseline Characteristics (SAS)

IGUMTXIGU+MTXNumber of Subjects297293305Age, mean (SD) years46.87(10.67)47.63(10.70)48.37(10.69)Female/male, %77.44/22.5679.18/20.8278.03/21.97Duration of RA, mean(SD) years11.67±7.1611.60±7.9811.67±7.27CRP, mean(SD) mg/L222.32±35.4720.67±26.6119.74±31.38Tender joint count, mean (SD)14.59±9.1614.83±9.3014.93±9.88Swollen joint count, mean (SD)9.81±6.639.73±7.209.51±6.22DAS28-CRP, mean (SD)5.084±0.9945.102±0.9795.103±0.956HAQ score, mean (SD)15.82±11.2515.24±10.9316.06±10.92

SAS: Safety Analysis Set; CRP: C-reactive protein;

DAS28: disease activity score; HAQ: Health Assessment Questionnaire

The study met its primary endpoints. More concretely, IGU monotherapy and IGU+MTX were found to be superior to MTX at week 52 with a higher ACR20 response of 77.44%(230/297, P=0.0019) and 77.05%(235/305, P=0.0028) versus 65.87%(193/293) (fig 1). As shown in fig 1, the structural remission (ΔmTSS≤0.5) was statistically significant for IGU monotherapy (57.4%, P=0.0308) but not for IGU+MTX arm (55%) versus MTX monotherapy (47.8%).

Overall incidence of the adverse events (AEs) leading to study discontinuation were reported in 13.8% (41/297) in IGU monotherapy arm, 11.26% (33/293) in MTX monotherapy arm and 11.51% (35/305) patients in IGU+MTX arm. The incidence of adverse drug reactions (ADR) leading to study discontinuation were 11.45% (34/297), 8.53% (25/293) and 9.21% (28/305), respectively. There was no one death and no significant difference in all the safety indicators among the three arms.

Conclusion:

Iguratimod alone or in combination with MTX demonstrated superior efficacy with acceptable safety compared to MTX for patients with active RA who have not previously used MTX bDMARDs.

Disclosure of Interests:

None declared

[Cognitive and gait dysfunction in the elderly caused by age-related cerebral small vessel disease and idiopathic normal pressure hydrocephalus: a case series of three patients]

Three cases with age-related cerebral small vessel disease and normal pressure hydrocephalus in the Department of Neurology of Sun Yat-sen University were retrospectively reviewed. All the patients exhibited gait disturbance, cognitive impairment and urinary incontinence. Meanwhile, the Craniocerebral imaging demonstrated cerebral small vessel disease and communicating hydrocephalus. The cerebralspinal fluid (CSF) Aβ42 levels decreased, and apolipoprotein E (APOE) genotypes were ε3/ε4,ε3/ε3,ε2/ε3, respectively. After treatment in an all-cause individualized manner, the symptoms of 3 patients were stable or improved.

Association Between Obesity and Histological Tumor Budding in Patients With Nonmetastatic Colon Cancer

IMPORTANCE

Obesity is associated with increased risk of colorectal cancer (CRC) and a more aggressive disease course. Tumor budding (TB) is an important prognostic factor for CRC, but its association with obesity is unknown.

OBJECTIVE

To evaluate the association of TB with obesity and other prognostic factors in colon cancer.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study involved a histological review of colon cancer specimens obtained during 7 years (January 2008 to December 2015) at the University of Kentucky Medical Center; data analysis was conducted from February 2020 to January 2021. Specimens came from 200 patients with stage I to III colon cancer; patients with stage 0, stage IV, or incomplete data were excluded.

MAIN OUTCOMES AND MEASURES

TB was defined as 1 to 4 malignant cells at the invasive edge of the tumor, independently assessed by 2 academic pathologists. The primary outcome was the association of TB with obesity (defined as body mass index [BMI] of 30 or greater). Secondary outcomes include the association of TB with clinical features (ie, age, race, sex, TNM stage, tumor location) and pathological features (ie, poorly differentiated tumor clusters [PDCs], Klintrup-Mäkinen inflammatory score, desmoplasia, infiltrative tumor border, tumor necrosis, and tumor-to-stroma ratio).

RESULTS

A total of 200 specimens were reviewed. The median (interquartile range) age of patients was 62 (55-72) years, 102 (51.0%) were women, and the mean (SD) BMI was 28.5 (8.4). A total of 57 specimens (28.5%) were from stage I tumors; 74 (37.0%), stage II; and 69 (34.5%), stage III. Of these, 97 (48.5%) had low-grade (<5 buds), 36 (18.0%) had intermediate-grade (5-9 buds), and 67 (33.5%) had high-grade (≥10 buds) TB. Multivariable analysis adjusting for clinical and histological factors demonstrated that higher TB grade was associated with obesity (odds ratio [OR], 4.25; 95% CI, 1.95-9.26), higher PDC grade (grade 2 vs 1: OR, 9.14; 95% CI, 3.49-23.93; grade 3 vs 1: OR, 5.10; 95% CI, 2.30-11.27), increased infiltrative tumor border (OR, 1.03; 95% CI, 1.01-1.04), cecal location (OR, 2.55; 95% CI, 1.09-5.97), and higher stage (eg, stage III vs stage I for high-grade or intermediate-grade vs low-grade TB: OR, 2.91; 95% CI, 1.00-8.49). Additionally, patients with a higher TB grade had worse overall survival (intermediate vs low TB: hazard ratio, 2.20; 95% CI, 1.11-4.35; log-rank P = .02; high vs low TB: hazard ratio, 2.67; 95% CI, 1.45-4.90; log-rank P < .001).

CONCLUSIONS AND RELEVANCE

In this cohort study, a novel association between high TB grade and obesity was found. The association could reflect a systemic condition (ie, obesity) locally influencing aggressive growth (ie, high TB) in colon cancer.

MiR-129-5p protects against myocardial ischemia-reperfusion injury via targeting HMGB1

OBJECTIVE

To investigate the protective effect of miR-129-5p on ischemia-reperfusion (I/R) injury via targeting high mobility group box-1 (HMGB1).

MATERIALS AND METHODS

Rat models of myocardial I/R and hypoxia/reoxygenation (H/R) cardiomyocytes were established, and the miR-129-5p and HMGB1 expression levels in myocardium of I/R rats and in cardiomyocytes of H/R rats were quantified by RT-PCR. The over-expression of miR-129-5p was performed on I/R rats, and the over-expression of miR-129-5p and down-regulation of HMGB1 were performed on cardiomyocytes of H/R rats. Triphenyltetrazolium chloride (TTC) staining was used to measure myocardial infarct size (IS). TUNEL (TdT-mediated dUTP end nick labeling) staining was employed to observe cardiomyocyte apoptosis in the myocardium of rats, and flow cytometry to observe cardiomyocyte apoptosis of I/R and H/R rats respectively. Dual-Luciferase reporter assay was used to verify the target relation between miR-129-5p and HMGB1.

RESULTS

MiR-129-5p was lowly expressed and HMGB1 was highly expressed in myocardial I/R injury rats and cardiomyocytes of H/R rats. Over-expression of miR-129-5p effectively reduced myocardial IS and cardiomyocyte apoptosis in rats with myocardial I/R injury, and significantly down-regulated the pro-apoptotic protein Bax, as well as significantly up-regulated the anti-apoptotic protein Bcl-2. Either over-expression of miR-129-5p or low-expression of HMGB1 in cardiomyocytes of H/R rats also achieved the same effects as described above. Dual-Luciferase reporter assay determined that miR-129-5p was a target for HMGB1.

CONCLUSIONS

MiR-129-5p plays a protective role on myocardial I/R injury by regulating HMGB1 expression. Besides, it inhibits cardiomyocyte apoptosis and is expected to become a novel molecular marker or therapeutic target for myocardial I/R injury.

Construction of an MnO2 nanosheet array 3D integrated electrode for sensitive enzyme-free glucose sensing

MnO₂ based electrochemical enzyme-free glucose sensors remain significantly limited by their low electronic conductivity and associated complex preparation. In this paper, an MnO₂ nanosheet array supported on nickel foam (MnO₂ NS/NF) was prepared using a simple hydrothermal synthesis and employed as a 3D integrated electrode for enzyme-free glucose detection. It was found that MnO₂ NS/NF shows high performance with a wide linear range from 1 μM to 1.13 mM, a high sensitivity of 6.45 mA mM^-1 cm^-2, and a low detection limit of 0.5 μM (S/N = 3). Besides, MnO₂ NS/NF shows high selectivity against common interferences and good reliability for glucose detection in human serum. This work demonstrates the promising role of MnO₂ NS/NF as an efficient integrated electrode in enzyme-free glucose detection with high performance.

[Effect of piRNA NU13 in regulating biological behaviors of human Wilms tumor cells in vitro]

OBJECTIVE

To investigate the role of the differential piRNA NU13 derived from piwil2-induced cancer stem-like cells (piwil2-iCSCs) in regulating biological behaviors of Wilms tumor cells (G401).

OBJECTIVE

The expressions of piRNA NU13 and NOP56 were detected in Wilms tumor cell line G401 using RT-qPCR. G401 cells were transfected with piRNA NU13 mimics and inhibitor for its over-expression and inhibition, and the transfection efficiency was verified with RT-qPCR. The changes in proliferation of G401 cells after transfection were detected using CCK8 assay, and cell apoptosis was analyzed using flow cytometry. Wound healing assay and Transwell assay were performed to examine the changes in migration and invasion abilities of the transfected cells. The binding of NOP56 and piRNA NU13 was detected using dual luciferase experiment. The protein expressions of MMP2, MMP9, BAX, Bcl2, and NOP56 in the cells were detected with Western blotting.

OBJECTIVE

RTqPCR showed that the expression of piRNA NU13 decreased significantly in human Wilms tumor G401 cells as compared with that in renal tubular epithelial cell line HK2 (P < 0.05), and NOP56 was highly expressed in G401 cells and Wilms tumor tissues (P < 0.05). Over-expression of piRNA NU13 significantly suppressed the proliferation, migration and invasion of G401 cells, promoted cell apoptosis (P < 0.05), inhibited the expression of MMP2, MMP9 and Bcl2, and enhanced the expression of BAX (P < 0.05). The results of dual luciferase experiment showed that piRNA NU13 did not bind to NOP56 directly but regulated the expression of NOP56 in an indirect manner.

OBJECTIVE

piRNA NU13 is down-regulated and NOP56 is highly expressed in Wilms tumor. piNU13 may regulate the expression of NOP56 indirectly to inhibit the proliferation, migration and invasion and promote apoptosis of Wilms tumor cells in vitro.

[Analysis of the catastrophic health expenditure of HIV-positive maternal households in high AIDS endemic areas in Liangshan prefecture]

Objective: To analysis the income and expenditure of HIV-positive pregnant women and the catastrophic health expenditure of their households in high AIDS endemic areas in Liangshan prefecture. Methods: From December 2018 to January 2019, a total of 250 pregnant women were recruited from 2 of 17 counties in Liangshan Prefecture, including 133 HIV-positive pregnant women and 117 HIV-negative pregnant women. The data, including basic information of pregnant women, basic information of the family, annual family income in 2017, annual family health expenditure in 2017, and maternal and child-related expenditure in 2017, were collected for analyzing the incidence of catastrophic health expenditure in the family. Results: The average annual income and average annual health expenditure of HIV-positive pregnant women households were 7 000 CNY and 2 000 CNY, while those of HIV-negative pregnant women households were 10 000 CNY and 3 000 CNY, respectively. Based on the criteria of 15%, 25% and 40%, the incidence of catastrophic health expenditure of HIV-positive pregnant households was 39.10%, 33.83% and 27.82%, with average differences of 34.84%, 31.17% and 26.65%, respectively, while that of HIV-negative pregnant women households was 38.46%, 33.33% and 23.93%, with average differences of 31.68%, 28.35% and 24.22%, respectively. Conclusion: The incidence of catastrophic health expenditure of pregnant households in high AIDS endemic areas in Liangshan prefecture is high. The incidence of HIV-positive families is slightly higher than that of HIV-negative families. We suggest that medical insurance compensation in Liangshan prefecture should be improved to reduce the impact of catastrophic health expenditure.