[The influence of Ras-associated binding protein 23 knockdown on the migration and invasion of esophageal squamous cell carcinoma cells and its mechanism]

Objective: To investigate the role and the mechanism of Ras-associated binding protein23 (RAB23) in the migration and invasion of esophageal squamous cell carcinoma (ESCC) cells. Methods: RAB23 mRNA levels were measured in 16 pairs of ESCC and adjacent normal tissues via real-time polymerase chain reactions. RAB23 mRNA levels in the ESCC and adjacent normal tissues of dataset GSE20347 deposited in the Gene Expression Omnibus (GEO) database were also analyzed. Immunohistochemistry (IHC) was used to detect the RAB23 protein expressions in 106 pairs of ESCC and adjacent normal tissues, as well as in the lymph glands and primary tumor tissues of 33 patients with positive lymph nodes and 10 patients with negative lymph nodes. Endogenous RAB23 expression was transiently depleted using siRNAs (si-NC, si-RAB23-1, and si-RAB23-9) or stably reduced using shRNAs (sh-NC and sh-RAB23) in ESCC KYSE30 and KYSE150 cells, and the knockdown efficiency was tested using Western blot assays. Cell counting kit-8 assays and mouse xenograft models were used to test the proliferation of ESCC cells. Transwell assays and tail vein-pulmonary metastasis models in immunocompromised mice were used to examine the migration and invasion of ESCC cells. Cell adhesion assays were used to test the adhesion of ESCC cells. RNA-seq assays were used to analyze how RAB23 knockdown influenced the expression profile of ESCC cells and the implicated signal pathways were confirmed using Western blot assays. Results: The RAB23 mRNA expression in 16 cases of ESCC tissues was 0.009 7±0.008 9, which was markedly higher than that in adjacent normal tissues (0.003 2±0.003 7, P=0.006). GEO analysis on RAB23 expressions in ESCC and adjacent normal tissues showed that the RAB23 mRNA level in ESCC tissues (4.30±0.25) was remarkably increased compared with their normal counterparts (4.10±0.17, P=0.037). Among the 106 pairs of ESCC and tumor-adjacent normal tissues, 51 cases exhibited low expression of RAB23 and 55 cases showed high expression of RAB23, whereas in the paired tumor-adjacent normal tissues 82 cases were stained weakly and 24 strongly for RAB23 protein. These results indicated that RAB23 expression was markedly increased in ESCC tissues (P<0.001). Additionally, only 1 out of 33 primary ESCC tissues with positive lymph nodes showed low RAB23 protein expression. On the other hand, 7 samples of primary ESCC tissues with negative lymph nodes were stained strongly for RAB23 while its level in the other 3 samples was weak. These results showed that RAB23 expression was remarkably increased in primary ESCC tissues with positive lymph nodes compared with those with negative lymph nodes (P=0.024). Further tests showed that 32 out of 33 positive lymph nodes were stained strongly for RAB23, whereas no negative lymph nodes (n=10) exhibited high expression of RAB23 (P<0.001). Both transient and stable knockdown of endogenous RAB23 expression failed to cause detectable changes in the proliferation of KYSE30 cells in vitro and in vivo, but attenuated the migration and invasion of KYSE30 cells as well as the invasion of KYSE150 cells. RAB23 knockdown was found to significantly decrease the number of adhesive KYSE30 cells in the sh-RAB23 group (313.75±89.34) compared with control cells in the sh-NC group (1 030.75±134.29, P<0.001). RAB23 knockdown was also found to significantly decrease the number of adhesive KYSE150 cells in the sh-RAB23 group (710.5±31.74) compared with the number of control cells in the sh-NC group (1 005.75±61.09, P<0.001). RNA-seq assays demonstrated that RAB23 knockdown using two siRNAs targeting RAB23 mRNA markedly impaired focal adhesion-related signal pathways, and decreased the levels of phosphorylated FAK (p-FAK) and phosphorylated paxillin (p-paxillin) in KYSE30 and KYSE150 cells. Conclusions: Significantly increased RAB23 in ESCC tissues positively correlates with lymph node metastasis. Depleted RAB23 expression attenuates focal adhesion-related signal pathways, thus impairing the invasion, metastasis, and adhesion of ESCC cells.

[Clinical implications of Naples prognostic scores in patients with resectable Siewert type II-III adenocarcinoma of the esophagogastric junction]

Objective: To evaluate the clinical value of preoperative Naples prognostic scores (NPS) in patients with resectable Siewert type II-III esophagogastric junction adenocarcinoma (AEG). Methods: In this retrospective observational study we collected and analyzed relevant data of patients with Siewert Type II-III AEG treated in the Department of Gastric Cancer, Tianjin Medical University Cancer Institute and Hospital from January 2014 to December 2018. NPS were calculated using preoperative albumin concentration, total cholesterol concentration, neutrophil/lymphocyte ratio, and lymphocyte/monocyte ratio and used to allocate patients into three groups: NTS-0 (0 points), NTS-1 (1-2 points) and NTS-2 (3-4 points). Kaplan-Meier was used to calculate disease-free survival (DFS) and overall survival (OS) in each NPS group and the log-rank test to compare these groups. Univariate and multivariate survival analyes were performed using the Cox regression model. Time-dependent receiver operating characteristic curves were constructed to compare the relationships between four commonly used tools for evaluating inflammatory responses and nutritional status:NPS, systemic inflammatory response scores, nutrient control status (CONUT), and prognostic nutrition index (PNI). Results: The study cohort comprised 221 patients with AEG of median age 63.0 (36.0-87.0) years. There were 190 men (86.0%) and 31 women (14.0%). As to pTNM stage, 47 patients (21.3%) had Stage I disease, 68 (30.8%) Stage II, and 106 (48.0%) Stage III. One hundred and forty-seven patients (66.5%) had Siewert Type II disease and 74 (33.5%) Siewert type III. There were 45 patients (20.4%) in the NPS-0, 142 (64.2%) in the NPS-1 and 34 (15.4%) in the NPS-2 groups. Higher NPS scores were significantly associated with older patients (χ²=5.056, P=0.027) and higher TNM stages (H=5.204,P<0.001). The median follow-up was 39 (6-105) months; 16 patients (7.2%) were lost to follow-up. The median OS in the NPS-0, NPS-1, and NPS-2 groups were 78.4, 63.1, and 37.0 months, respectively; these differences are statistically significant (P=0.021). Univariate and multivariate Cox regression analysis identified the following as independently and significantly associated with OS in patients with Siewert Type II-III: TNM stage (Stage II: HR=2.182, 95%CI: 1.227-3.878, P=0.008; Stage III: HR=3.534, 95%CI: 1.380-6.654, P<0.001), tumor differentiation (G3: HR=1.995, 95%CI: 1.141-3.488, P=0.015), vascular invasion (HR=2.172, 95%CI: 1.403-3.363, P<0.001), adjuvant chemotherapy (HR=0.326, 95%CI: 0.200-0.531, P<0.001), NPS (NPS-1: HR=2.331, 95%CI: 1.371-3.964, P=0.002; NPS-2: HR=2.494, 95%CI: 1.165-5.341, P=0.019), SIS group (NPS-1: HR=2.170, 95%CI: 1.244-3.784, P=0.006; NPS-2: HR=2.291, 95%CI: 1.052-4.986, P=0.037), and CONUT (HR=1.597, 95% CI: 1.187-2.149, P=0.038). The median DFS in the NPS-0, NPS-1, and NPS-2 groups was 68.6, 52.5, and 28.3 months, respectively; these differences are statistically significant (P=0.009). Univariate and multivariate Cox regression analysis identified the following as independently and significantly associated with DFS in patients with Siewert Type II-III AEG: TNM stage (StageⅡ: HR=2.789, 95%CI:1.210-6.428, P=0.016; Stage III: HR=10.721, 95%CI:4.709-24.411, P<0.001), adjuvant chemotherapy (HR=0.640, 95% CI: 0.432-0.946, P=0.025), and NPS (NPS-1: HR=1.703, 95%CI: 1.043-2.782, P=0.033; NPS-2: HR=3.124, 95%CI:1.722-5.666, P<0.001). Time-dependent receiver operating characteristic curves showed that NPS was more accurate in predicting OS and DFS in patients with Siewert Type II-III AEG than were systemic inflammatory response scores, CONUT, or PNI scores. Conclusion: NPS is associated with age and TNM stage, is an independent prognostic factor in patients who have undergone resection of Siewert type II-III AEG, and is better than SIS, CONUT, or PNI in predicting survival.

Prognostic value of multiphase CT angiography: estimated infarct core volume in the patients with acute ischaemic stroke after mechanical thrombectomy

BACKGROUND AND PURPOSE

Recent studies reported the feasibility of quantifying a reliable infarct core (IC) volume using multiphase computed tomography (mCTA) based on deep learning, however its prognostic value was not fully clarified. Therefore, we aimed to evaluate the prognostic value of mCTA-estimated IC volume in patients with acute ischemic stroke (AIS) after mechanical thrombectomy (MT).

MATERIALS AND METHODS

We retrospectively reviewed patients who underwent mCTA and MT for large vessel occlusion in middle cerebral artery and (or) internal carotid artery within 6 hours after symptom onset between January 2018 and November 2019. Patients were dichotomized into good (modified Rankin Scale [mRS] score, 0-2) and poor (mRS, 3-6) outcome groups. mCTA-estimated IC volume were generated based on a multi-scale three-dimensional convolutional neural network. Univariate, multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were used to identify the independent variables, and evaluate their performances in predicting the clinical outcome.

RESULTS

Of 44 included patients, 27 (61.4%) patients achieved good outcome. National Institutes of Health Stroke Scale scores at admission [NIHSSpre] (odds ratio [OR], 1.191; 95%confidence interval [CI], 1.028-1.379; P=0.020) and mCTA-estimated IC volume (OR, 1.076; 95%CI, 1.016-1.140; P=0.013) were found to be independently associated with functional outcome in patients with AIS after MT. After integrating NIHSSpre and mCTA-estimated IC volume, optimal performance (area under the ROC curve, 0.874; 95%CI, 0.739-0.954) could be obtained in predicting the clinical outcome.

CONCLUSIONS

mCTA-estimated IC volume might be promising for predicting the prognosis, and assisting in making individualized treatment decision in patients with AIS.

Digital finance and M&As: An empirical study and mechanism analysis

With the rapid growth and wide application of digital technology, enterprises have entered the digital era with both opportunities and challenges existing. Mergers and acquisitions are one of the most efficient ways to integrate resources and achieve profit growth, giving enterprises advantages in competing in the new mode of economic growth. Based on this, this research tries to explore whether the development of digital finance will contribute to the emergence of M&As activities through combining M&As data of the Chinese stock market with the digital finance inclusion index between 2012 and 2020. The results show that the development of digital finance largely influences M&As activities through lower acquirers' financial constraints. We further replace digital finance with three sub-indexes including coverage breadth, usage depth, and digitalization level to explore the impact of different dimensions of digital finance on M&As. Results show that coverage breadth plays a more important role. In addition, heterogeneity tests reveal that the relationship between the development of digital finance and M&As activities varies significantly. The influences of digital finance on private and western and central enterprises are more significant compared with state-owned and eastern enterprises. According to the study, since the development of digital finance can be an efficient way to ease financial constraints and boost M&As activities, the government should promote the development of digital finance while companies strive to make the most use of it.

Mouth breathing induces condylar remodelling and chondrocyte apoptosis via both the extrinsic and mitochondrial pathways in male adolescent rats

The prevalence of mouth breathing is high in children and adolescents. It causes various changes to the respiratory tract and, consequently, craniofacial growth deformities. However, the underlying mechanisms contributing to these effects are obscure. Herein, we aimed to study the effects of mouth breathing on chondrocyte proliferation and death in the condylar cartilage and morphological changes in the mandible and condyle. Additionally, we aimed to elucidate the mechanisms underlying chondrocyte apoptosis and investigate any variations in the related pathways. Subchondral bone resorption and decreased condylar cartilage thickness were observed in mouth-breathing rats; further, mRNA expression levels of Collagen II, Aggrecan, and Sox 9 were lower in the mouth breathing group, while those of matrix metalloproteinase 9 increased. TdT-mediated dUTP nick end labelling staining and immunohistochemistry analyses showed that apoptosis occurred in the proliferative and hypertrophic layers of cartilage in the mouth breathing group. TNF, BAX, cytochrome c, and cleaved-caspase-3 were highly expressed in the condylar cartilage of the mouth-breathing rats. These results suggest that mouth breathing leads to subchondral bone resorption, cartilage layer thinning, and cartilage matrix destruction, inducing chondrocyte apoptosis via both the extrinsic and mitochondrial apoptosis pathways.

Abstract 5175: DX-002, a dual EP2 and EP4 antagonist, alters the tumor microenvironment to enhance tumor immunogenicity and responses to immune checkpoint inhibitors

Prostaglandin E2 (PGE2) generated by the cyclooxygenase (COX) pathways regulates both inflammation and tumor microenvironment (TME). Among the four E-type prostanoid receptors EP1-4, it has been demonstrated that PGE2 exhibits its immune suppression and tumorigenic function through engagement with EP2 and EP4. Mechanistically, tumor-derived PGE2 acts on EP2 and EP4 in immune cells (e.g., NK cells and dendritic cells) and elicits immunosuppression in TME1,2. Importantly, the deletion of both EP2 and EP4, but not deletion of either receptor, is required to reverse PGE2-mediated immune evasion. Furthermore, high levels of PGE2-EP2/EP4 associated inflammatory signature have been shown in multiple human cancer types to correlate with poor prognosis and worse response to immune checkpoint blockade in the clinic1. Therefore, PGE2-EP2/EP4 signaling likely acts as a key regulatory node linking inflammation and immunosuppression in TME, and its inhibition may lead to a less immunosuppressive TME and enhance the response to immune checkpoint inhibitors. COX inhibitors have been used to block PGE2 synthesis but cause cardiovascular and gastrointestinal risks due to the inhibition of all prostanoids synthesis3. Thus, therapeutically targeting both EP2 and EP4 is an effective and more selective approach to limit the immunosuppressive functions of PGE2 while avoiding potential side effects associated with COX inhibition.

Here we describe the discovery of a potent and selective EP2/EP4 dual antagonist DX-002. At 10 nM concentration, it displayed &gt;90% inhibition of PGE2 binding to EP2 or EP4, whereas no significant inhibition was seen towards PGE2 binding to EP1 or EP3. In human NK cells DX-002 reversed PGE2-mediated inhibition of IFN-γ production more potently than selective EP2 or EP4 antagonist. DX-002 has excellent pharmacokinetics profiles across all animal species. In the mouse tumor model, treatment of DX-002 produced superior tumor regression as a monotherapy over selective EP2 or EP4 antagonists. In addition, DX-002 also provided significant synergistical effect for tumor regression in combination with anti-PD1 in both immune checkpoint inhibitor insensitive and sensitive models, in association with increased tumor infiltration of CD8+ T cells. Based on its in vitro and in vivo profiles along with other properties, DX-002 is being profiled as a development candidate as a potential cancer immunotherapeutic agent.

Citation Format: Lintong Li, Guorui Yao, Wei Zheng, Yongshuai Chai, Zhongying Huang, Guojian Ma, Linlin Nie, Dengfeng Xu, Jiuquan Yang, Nanxin Li. DX-002, a dual EP2 and EP4 antagonist, alters the tumor microenvironment to enhance tumor immunogenicity and responses to immune checkpoint inhibitors. [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 5175.

Bacterial antibiotic resistance among cancer inpatients in China: 2016-20

BACKGROUND

The incidence of infections among cancer patients is as high as 23.2-33.2% in China. However, the lack of information and data on the number of antibiotics used by cancer patients is an obstacle to implementing antibiotic management plans.

AIM

This study aimed to investigate bacterial infections and antibiotic resistance in Chinese cancer patients to provide a reference for the rational use of antibiotics.

DESIGN

This was a 5-year retrospective study on the antibiotic resistance of cancer patients.

METHODS

In this 5-year surveillance study, we collected bacterial and antibiotic resistance data from 20 provincial cancer diagnosis and treatment centers and three specialized cancer hospitals in China. We analyzed the resistance of common bacteria to antibiotics, compared to common clinical drug-resistant bacteria, evaluated the evolution of critical drug-resistant bacteria and conducted data analysis.

FINDINGS

Between 2016 and 2020, 216 219 bacterial strains were clinically isolated. The resistance trend of Escherichia coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, cefotaxime, piperacillin/tazobactam and imipenem was relatively stable and did not significantly increase over time. The resistance of Pseudomonas aeruginosa strains to all antibiotics tested, including imipenem and meropenem, decreased over time. In contrast, the resistance of Acinetobacter baumannii strains to carbapenems increased from 4.7% to 14.7%. Methicillin-resistant Staphylococcus aureus (MRSA) significantly decreased from 65.2% in 2016 to 48.9% in 2020.

CONCLUSIONS

The bacterial prevalence and antibiotic resistance rates of E. coli, K. pneumoniae, P. aeruginosa, A. baumannii, S. aureus and MRSA were significantly lower than the national average.

Current census of oncology critical care medicine in China

OBJECTIVE

The purposes of this survey were to show the current situation of oncology critical care medicine in China by questionnaire, to understand the resource distribution of oncology critical care medicine and to analyze and evaluate the existing resources and reserve capacity of oncology critical care medicine in China.

METHODS

We conducted the survey mainly in the form of an online questionnaire. The Committee of Cancer Critical Care Medicine of the Chinese Anticancer Association (CACA) initiated the survey on 1 November 2017, and 36 member hospitals nationwide participated in the survey. The questionnaire included 10 items: investigator information, hospital information, general information of oncology critical care department, staffing of oncology critical care department, management in oncology critical care department, technical skills in oncology critical care department, patient source in oncology critical care department, equipment configuration in oncology critical care department, special skills in oncology critical care department and summary of the information.

RESULTS

The survey results included information from 28 member units, all of which were tertiary hospitals, distributed in 20 provinces and 4 direct-controlled municipalities. The results are as follows. (i) The total ratio of beds in the oncology critical care department to hospital beds was 1.06%, and the average number of beds in the oncology critical care department was 16.36. (ii) The ratio of physicians in the oncology critical care department to beds was ∼0.62:1, and the ratio of nurses to beds was ∼1.98:1. (iii) According to the census of the population and gross domestic product (GDP) of different regions conducted by the State Statistics Bureau in 2017, the ratio of beds in the oncology critical care department for tumor patients to the population was 4.55 beds per 10 million people, and the ratio of beds in the oncology critical care department to GDP was 8.00 beds per RMB 100 billion, on average. (iv) According to the requirements of the guidelines for the development and management of critical care medicine in China, the facilities in departments of oncology critical care medicine meet the requirements, and the technical skills of medical staff are competent.

CONCLUSION

The development of oncology critical care in China is becoming better, but there is still a certain gap compared with the intensive care unit standards in China and the average level of the nationwide. The development of oncology critical care medicine is urgent.

MRI-based radiomics analysis in differentiating solid non-small-cell from small-cell lung carcinoma: a pilot study

AIM

To investigate the ability of a T2-weighted (W) magnetic resonance imaging (MRI)-based radiomics signature to differentiate solid non-small-cell lung carcinoma (NSCLC) from small-cell lung carcinoma (SCLC).

MATERIALS AND METHODS

The present retrospective study enrolled 152 eligible patients (NSCLC = 125, SCLC = 27). All patients underwent MRI using a 3 T scanner and radiomics features were extracted from T2W MRI. The least absolute shrinkage and selection operator (LASSO) logistic regression model was used to identify the optimal radiomics features for the construction of a radiomics model to differentiate solid NSCLC from SCLC. Threefold cross validation repeated 10 times was used for model training and evaluation. The conventional MRI morphology features of the lesions were also evaluated. The performance of the conventional MRI morphological features, and the radiomics signature model and nomogram model (combining radiomics signature with conventional MRI morphological features) was evaluated using receiver operating characteristic (ROC) curve analysis.

RESULTS

Five optimal features were chosen to build a radiomics signature. There was no significant difference in age, gender, and the largest diameter. The radiomics signature and conventional MRI morphological features (only pleural indentation and lymph node enlargement) were independent predictive factors for differentiating solid NSCLC from SCLC. The area under the ROC curves (AUCs) for MRI morphological features, and the radiomics model, and nomogram model was 0.69, 0.85, and 0.90 (ROC), respectively.

CONCLUSIONS

The T2W MRI-based radiomics signature is a potential non-invasive approach for distinguishing solid NSCLC from SCLC.

Breakthrough Path of Low-Level Equilibrium of China's Policy-Oriented Financing Guarantee Market

Policy-oriented financing guarantee schemes are widely adopted in the world to alleviate the financing difficulties of small and medium-sized enterprises. However, the development level of policy-oriented financing guarantee market in China has not reached the desired high-level equilibrium target, even though governments have issued a series of guiding policies. Accordingly, based on the evolutionary game theory, this study establishes and analyzes the game model between local governments, guarantee institutions, and banks. Then, the breakthrough effects of different paths on the low-level equilibrium of the guarantee market are simulated. The results show that strengthening superior government's performance appraisal intensity can only partially delay the “window period” of the low-level equilibrium, while adjusting local governments' compensation coefficients or increasing banks' risk sharing ratio have further synergistic effects on the realization of the high-level equilibrium. Additionally, dynamic reward and penalty mechanism of the local governments can effectively restrain the unbalanced state of financing guarantee market caused by banks' excess compensation risk, and finally impel the stabilization of the high-level equilibrium state.

Detection of Appearance and Behavior Anomalies in Stationary Camera Videos Using Convolutional Neural Networks

The automatic detection and tracking of appearance and behavior anomalies in video surveillance systems is one of the promising areas for the development and implementation of artificial intelligence. In this paper, we present a formalization of these problems. Based on the proposed generalization, a detection and tracking algorithm that uses the tracking-by-detection paradigm and convolutional neural networks (CNNs) is developed. At the first stage, people are detected using the YOLOv5 CNN and are marked with bounding boxes. Then, their faces in the selected regions are detected and the presence or absence of face masks is determined. Our approach to face-mask detection also uses YOLOv5 as a detector and classifier. For this problem, we generate a training dataset by combining the Kaggle dataset and a modified Wider Face dataset, in which face masks were superimposed on half of the images. To ensure a high accuracy of tracking and trajectory construction, the CNN features of the images are included in a composite descriptor, which also contains geometric and color features, to describe each person detected in the current frame and compare this person with all people detected in the next frame. The results of the experiments are presented, including some examples of frames from processed video sequences with visualized trajectories for loitering and falls.

Detection of Brucella spp. during a serosurvey of pig-hunting and regional pet dogs in eastern Australia

Brucellosis is a zoonotic disease with worldwide distribution. Brucella suis serotype 1 is thought to be maintained in the Australian feral pig population, with disease prevalence higher in Queensland (Qld) than New South Wales (NSW). Pig hunting is a popular recreational activity in rural Qld and NSW, with feral pigs in these states thought to carry B. suis. Brucellosis associated with B. suis has been diagnosed in dogs engaged in pig hunting in some of these areas. A total of 431 dogs from northern Qld and north‐west NSW were recruited. Two distinct cohorts of clinically healthy dogs were tested – (1) 96 dogs from central, north and far north Queensland actively engaged in pig‐hunting and (2) 335 dogs from rural and remote north‐west NSW that were primarily companion (non‐pig hunting) animals. Serum samples were tested for antibodies to Brucella spp. using the Rose Bengal test (RBT) test followed by complement fixation testing (CFT) for RBT‐positive samples. A subset of samples was retested using RBT and CFT. Seven dogs were considered seropositive for B. suis from Qld and remote NSW, including 4/96 (4.2%; 95% CI 3.5% to 4.3%) from the pig‐hunting cohort and 3/335 (0.9%) from the regional pet dog cohort. The use of RBT and CFT in dogs to detect anti‐Brucella antibodies requires validation. Veterinarians treating pig‐hunting dogs and physicians treating pig hunters in central, north and far north Qld need to be aware of the zoonotic risk posed by B. suis to these groups.

Optical coherence tomography-defined vulnerable plaque characteristics in relation to functional severity of coronary stenoses stratified by quantitative flow ratio

Background

The functional severity and morphological features of epicardial lesions are both related to plaque vulnerability and adverse coronary events. However, their relationship remains controversial, especially in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

Purpose

This study aimed to examine whether quantitative flow ratio (QFR), an angiography-based computation of fractional flow reserve, was associated with optical coherence tomography (OCT)-defined vulnerable plaques such as thin-cap fibroatheromas (TCFAs) in a board spectrum of population, including patients presenting stable angina and NSTE-ACS.

Methods

We identified patients who underwent OCT examinations from 2 prospective cohorts and then assessed interrogated vessels with QFR. Lesions were divided into tertiles: QFR-T1 (QFR &lt;0.85)&lt;qfr),&gt;, QFR-T2 (0.85 to 0.93) and QFR-T3 (QFR &gt;0.93).

Results

This post-hoc analysis included 83 lesions from 79 patients (mean age: 61.5±9.8 years, males: 58%). Patients with NSTE-ACS accounted for the majority of the population (67%). The median % diameter stenosis and median QFR value were 42% (36 to 49%) and 0.88 (0.83 to 0.95), respectively. The prevalence of OCT-TCFA was significantly higher in QFR-T1 (50%) than in QFR-T2 (14%) and QFR-T3 (19%) (p=0.003 and 0.018, respectively). Overall significant differences were observed among tertiles in maximum lipid arc, thinnest fibrous cap thickness (FCT), and minimal lumen area (MLA) (p=0.017, 0.040, and &lt;0.001, respectively). The Spearman's correlation analysis showed that QFR was significantly related to MLA (ρ = 0.537, p&lt;0.001), % area stenosis (ρ = –0.512, p&lt;0.001), maximum lipid arc (ρ = –0.360, p=0.002), lipid length (ρ = –0.242, p=0.038), lipid index (ρ = –0.333, p=0.004), and thinnest FCT (ρ = 0.315, p=0.006). In the multivariable analysis, QFR ≤0.80 remained as a significant determinant of TCFAs regardless of the presence of NSTE-ACS and the level of low-density lipoprotein cholesterol (adjusted odds ratio = 4.387, 95% confidence interval: 1.297 to 14.839, p=0.017). In addition, QFR demonstrated moderate predictive ability for OCT-TCFA (area under the curve = 0.72, 95% confidence interval: 0.58 to 0.86, p=0.003) with the best cutoff of ≤0.86 (sensitivity: 65%; specificity: 73%; negative predictive value: 85%; accuracy: 71%).

Conclusions

Lower QFR was related to OCT-TCFA and other vulnerable plaque characteristics in angiographically mild-to-intermediate stable lesions and culprit lesions from NSTE-ACS. The QFR might be a useful tool for ruling out high-risk, rupture-prone plaques without using any pressure wires or vasodilators.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The Jiangsu Provincial Key Research and Development Program Flow diagram of patient selectionOCT findings according to QFR tertiles

A Broad-Spectrum Catalytic Amidation of Sulfonyl Fluorides and Fluorosulfates*

A broad-spectrum, catalytic method has been developed for the synthesis of sulfonamides and sulfamates. With the activation by the combination of a catalytic amount of 1-hydroxybenzotriazole (HOBt) and silicon additives, amidations of sulfonyl fluorides and fluorosulfates proceeded smoothly and excellent yields were generally obtained (87-99 %). Noticeably, this protocol is particularly efficient for sterically hindered substrates. Catalyst loading is generally low and only 0.02 mol % of catalyst is required for the multidecagram-scale synthesis of an amantadine derivative. In addition, the potential of this method in medicinal chemistry has been demonstrated by the synthesis of the marketed drug Fedratinib via a key intermediate sulfonyl fluoride 13. Since a large number of amines are commercially available, this route provides a facile entry to access Fedratinib analogues for biological screening.

Photoredox initiated azole-nucleophilic addition: oxo-azolation of gem-difluoroalkenes

A protocol for photoredox initiated oxo-azolation of gem-difluoroalkenes has been demonstrated. The strategy offers a facile access to a series of synthetically useful azolated difluoroacetonarenes and tolerates a wide range of functional groups.

Effect of COVID-19 on delivery plans and postnatal depression scores of pregnant women

INTRODUCTION

Owing to the coronavirus disease 2019 outbreak Hong Kong hospitals have suspended visiting periods and made mask wearing mandatory. In obstetrics, companionship during childbirth has been suspended and prenatal exercises, antenatal talks, hospital tours, and postnatal classes have been cancelled. The aim of the present study was to investigate the effects of these restrictive measures on delivery plans and risks of postpartum depression.

METHODS

We compared pregnancy data and the Edinburgh Postpartum Depression Scale (EPDS) scores of women who delivered between the pre-alert period (1 Jan 2019 to 4 Jan 2020) and post-alert period (5 Jan 2020 to 30 Apr 2020) in a tertiary university public hospital in Hong Kong. Screening for postpartum depression was performed routinely using the EPDS questionnaire 1 day and within 1 week after delivery.

RESULTS

There was a 13.1% reduction in the number of deliveries between 1 January and 30 April from 1144 in 2019 to 994 in 2020. The EPDS scores were available for 4357 out of 4531 deliveries (96.2%). A significantly higher proportion of women had EPDS scores of ≥10 1 day after delivery in the post-alert group than the pre-alert group (14.4% vs 11.9%; P<0.05). More women used pethidine (6.2% vs 4.6%) and fewer used a birthing ball (8.5% vs 12.4%) for pain relief during labour in the post-alert group.

CONCLUSIONS

Pregnant women reported more depressive symptoms in the postpartum period following the alert announcement regarding coronavirus infection in Hong Kong. This was coupled with a drop in the delivery rate at our public hospital. Suspension of childbirth companionship might have altered the methods of intrapartum pain relief and the overall pregnancy experience.

Apical sparing strain pattern observed in danon disease: insights from a global registry

Background

Danon Disease (DD) is a rare X-linked autophagic disorder due to mutations in the Lysosomal Associated Membrane Protein 2 (LAMP-2) gene and causes severe cardiac manifestations. Measurement of longitudinal strain (LS) has been shown to provide diagnostic insights into different etiologies of hypertrophic cardiomyopathies compared to conventional echocardiographic parameters.

Purpose

The aim of this study was to describe the pattern of global and regional LS in DD.

Methods

A retrospective, international registry, using medical records provided by patients, was formed to describe the natural history of DD. Complete echocardiogram images were available for review and LS was analyzed globally and regionally (basal, mid, apex).

Results

A total of eighteen DD patients (male 72%, mean age 17.2±10 years) had sufficient quality echocardiographic images for both traditional and myocardial strain evaluation. Notable traditional echocardiographic parameters included a mean EF of 60±11%, LV mass index 200±159 g/m2, intraventricular septal diameter 17.7±10.3 mm, LV posterior wall diameter 16.1±7.7 mm, LA volume index 21.9±13 mL/m2. Global longitudinal strain was reduced with a mean of −12.1±4.9% with an observed regional strain gradient: apex (−16.6±6.6%), mid (−10.9±4.7%) and basal (−9.2±4.5%). Bull's eye plot patterns reflected an apical sparing pattern that was similar to that described in cardiac amyloidosis.

Conclusion

In this DD cohort, we describe for the first time a strain pattern characterized by reduction in global longitudinal strain with apical sparing, which was originally pathognomonic for cardiac amyloidosis. This strain pattern in conjunction with a paradoxically normal LA volume may discriminate patients with DD from other hypertrophic conditions.

Funding Acknowledgement

Type of funding source: None

Knockdown of long noncoding RNA SNHG7 inhibits the proliferation and promotes apoptosis of thyroid cancer cells by downregulating BDNF

OBJECTIVE

Recently, long noncoding RNAs (lncRNAs) have got much attention for their role in tumor progression. LncRNA small nucleolar RNA host gene 7 (SNHG7) was studied in this research to identify how it affects the development of thyroid cancer (TC).

PATIENTS AND METHODS

SNHG7 expression was detected by quantitative Real-time polymerase chain reaction (qRT-PCR) in both TC cells and tissue samples. Pearson's Chi-square test was used to determine the association of SNHG7 expression with several clinicopathological factors. Moreover, colony formation assay, cell proliferation and cell apoptosis assay were conducted. In addition, by performing qRT-PCR and Western blot assay, the underlying mechanism was explored.

RESULTS

SNHG7 expression level was higher in TC samples than that in corresponding ones. The SNHG7 expression was associated with tumor size and TNM stage. Moreover, TC cell proliferation was inhibited, and TC cell apoptosis was induced after SNHG7 was knocked down in vitro. Moreover, the mRNA and protein expressions of brain-derived neurotrophic factor (BDNF) were downregulated after knockdown of SNHG7. Furthermore, the expression level of BDNF was positively related to the expression of SNHG7 in TC tissues.

CONCLUSIONS

These results suggested that knockdown of SNHG7 could inhibit TC cell proliferation and induce cell apoptosis via downregulating BDNF, which might be a potential therapeutic target in TC.

Replacing true unenhanced imaging in renal carcinoma with virtual unenhanced images in dual-energy spectral CT: a feasibility study

AIM

To investigate the clinical value of virtual unenhanced (VNC) spectral computed tomography (CT) images to replace the conventional true unenhanced spectral CT images (TNC) in diagnosing renal carcinoma.

MATERIALS AND METHODS

Fifty-six cases of renal carcinoma confirmed by histopathology underwent conventional plain CT and contrast-enhanced spectral CT at arterial phase (AP) and venous phase (VP). VNC images were generated on an AW4.6 workstation. The CT attenuation, image noise, contrast-to-noise ratio (CNR), and signal-noise-ratio (SNR) of the renal lesions and normal kidneys, long and short axis diameters of the lesion were measured from the three image sets and analysed using one-way analysis of variance (ANOVA). Two radiologists evaluated image quality subjectively using a five-point score, and lesion signature using a three-point score. Image quality scores were compared statistically and tested for consistency.

RESULTS

The two reviewers had good agreement for subjective evaluation (Kappa>0.70) and there was no difference in the quality of the scores among the three image groups. The lesion signature scores were all above the acceptable level. The CNR and SNR values in VNC were significantly higher than in TNC (p<0.05). VNC images had lower renal noise than in TNC (p<0.05). There was no difference in the long and short axis diameters of the lesion among the three image groups. VNC had higher CT attenuation values for the lesion and kidney than TNC (p<0.05), but the differences were <5 HU.

CONCLUSION

VNC images in spectral CT may be used to replace the conventional plain CT to reduce imaging duration and radiation dose in diagnosing renal carcinoma.

Current research and prevention of aflatoxins in China

Since their discovery in the 1960s, aflatoxins were found to have a considerable impact on the health of humans and animals as well as the country’s economy and international trade. Aflatoxins are often found in nuts, cereals and animal feeds, which has a significant danger to the food industry. Over the years, several steps have been undertaken worldwide to minimise their contamination in crops and their exposure to humans and animals. China is one of the largest exporters and importers of food and animal feed. As a result, many studies have been carried out in China related to aflatoxins, including their distribution, pollution, detection methods, monitoring, testing and managing. Chinese scientists studied aflatoxins in microbiological, toxicological, ecological effects as well as policies relating to their controlling. China has thus put into practice a number of strategies aiming at the prevention and control of aflatoxins in order to protect consumers and ensure a safe trade of food and feed, and the status and enlargement of these strategies are very important and useful for many consumers and stakeholders in China. Therefore, this article aims at the detriment assessments, regulations, distribution, detection methods, prevention and control of aflatoxins in China. It equally provides useful information about the recent safety management systems in place to fight the contamination of aflatoxins in food and feed in China.

KMT2D and TP53 mutation status improve the prognostic value of the International Prognostic Index (IPI) stratification in ENKTL patients

Extranodal NK/T-cell lymphoma nasal type (ENKTL) is a subtype of T cell lymphoma with poor prognosis. In this study, we designed a new prognostic model specifically for ENKTL to improve the risk stratification. In 29 ENKTL patients, we screened mutations in 9 ENKTL-associated genes using next-generation sequencing (NGS). We have found that mutated KMT2D was associated with the inferior overall survival (OS) and progression free survival (PFS) and KMT2D or TP53 mutations were associated with a higher mortality rate. Moreover, the difference in PFS among different stratifications was not significant using the International Prognostic Index (IPI) alone but was significant after the mutation status of KMT2D and TP53 were incorporated into the IPI model, forming a harmonious risk stratification reflecting the clinical features and genetic information of ENKTL. In summary, we demonstrate that the prognostic value of the IPI system can be enhanced by integrating the status of genetic mutations.

Facile One-pot Protocol of Derivatization Nitropyridines: Access to 3-Acetamidopyridin-2-yl 4-methylbenzenesulfonate Derivatives

This paper discloses an efficient one-pot protocol to convert easily accessible 3-nitropyridines to 3-acetamidopyridin-2-yl 4-methylbenzenesulfonate derivatives which are core structures of many pharmaceutical molecules. The strategy successfully combined a three-step reaction in one pot via progressively adding different reactants at rt. The reaction displays good functional group tolerance and regioselectivity. Structurally diversified 3-nitropyridine could be time-efficiently (3.5 h) derivatized to various functional 2-O,3-N-pyridines which are apt for further elaborations. The transformation was amenable to gram-scale synthesis.

Overexpression of UBE2C correlates with poor prognosis in gastric cancer patients

OBJECTIVE

The ubiquitin-conjugating enzyme E2C (UBE2C) has been known as a crucial factor upregulated in various tumors. The functions of UBE2C is mainly involved in the pathway protein ubiquitination. This study investigates the expression of UBE2C in gastric cancers and its correlation with overall survival rate.

MATERIALS AND METHODS

Real-time PCR (RT-PCR) and Western blotting were performed to determine the expression of UBE2C in gastric cancer samples and adjacent normal tissues. Immunohistochemical staining was used to assess the expression of UBE2C in 216 paraffin-embedded gastric cancer tissues.

RESULTS

The mRNA and relevant protein levels of UBE2C in gastric cancer tissues are significantly greater than those in the adjacent normal tissues. Also, the expression of UBE2C is found to correlate with lymphatic metastasis, serosa invasion, TNM (Malignant Tumors) staging and Lauren's classification (p<0.05). The univariate analysis shows that the overexpression of UBE2C associates with poor prognosis (p=0.001). The multivariate analysis demonstrates that expression of UBE2C, lymphatic metastasis, and TNM staging are independent prognostic indicators.

CONCLUSIONS

This study shows that overexpression of UBE2C contributes to the development of gastric cancer, and UBE2C has the potential to be exploited as a therapeutic target.

Twist2 and CD24 expression alters renal microenvironment in obesity associated kidney cancer

OBJECTIVE

Obesity emerged as a major public health problem worldwide, and prolonged condition with increased BMI causes various metabolic disorders include the development of kidney cancer. The metabolic changes alter the renal microenvironment and thereby promoting tumor. Hence, detailed studies of genes that regulate these this changes are keen to understand.

MATERIALS AND METHODS

Initially, we successfully initiate kidney tumor using prolonged intake of a high-fat diet in Wistar rats, which are confirmed with pathological changes observed through histological sectioning. The expression of Twist2 and CD24 was assessed using Immunohistology and Western Blotting in a different time interval of kidney cancer.

RESULTS

The rats fed with high-fat diet for 8 months shows 1.5 times increased in body mass whereas rats fed with high-fat diet for 16 months shows triple the size when compared with controls. Histological sectioning confirms the development of lesions and proteinaceous casts in 8 months high-fat fed rats, whereas we observed the high proliferative mass of cells in 16 months high-fat fed rats. Interestingly, we also observed elevated expression of Twist2 in initial stages of kidney cancer, which are down-regulated in the latter stages of kidney cancer. The experiments with CD24 shows the gradual increase of the expression of CD24 as a tumor develops to the next level.

CONCLUSIONS

The correlation between Twist2 and CD24 expression conclude that Twist2 overexpression in initial stage augments CD24 to express more in the latter stage of kidney cancer. Reversely, the overexpression of CD24 and down-regulation of Twist2 in later stages of kidney cancer suggest the CD24 expression is dependent on Twist2 expression level.

P902Danon disease: clinical features and outcomes

Background

Danon Disease (DD) is a rare X-linked autophagic vacuolar myopathy, characterized by high penetrance and severe cardiomyopathy; cognitive, skeletal muscle and vision impairment may occur as well. Due to its rarity, clinical presentation and outcomes are still uncertain.

Purpose

To describe clinical features and outcomes of DD in female and male patients

Methods

Individuals and families from United Kingdom, Australia, and United States were recruited through via advertisements on Facebook groups related to DD. Participants completed a survey about symptoms and medical history and provided their medical records to the research team.

Results

A total of 44 patients (54.5% female) with positive genetic testing for DD were included. De novo mutations occurred in one out of four patients. Cardiomyopathy occurred in 86.3% of patients (18/24 females, 20/20 males) at a mean age of 7.3 years for males and 19.4 years for females (p=0.001). Females presented with either hypertrophic cardiomyopathy (HCM, 66.7%) or dilated cardiomyopathy (DCM, 8.3%) whereas males presented with HCM 90% of the time. 34.2% of patients were diagnosed with Wolff-Parkinson-White syndrome.

Twelve patients (7 females, 5 males) underwent cardiac magnetic resonance (CMR) Out of the 9 cases, 8 (88.9%) exhibited extensive patchy late gadolinium-enhancement (LGE) in multiple segments of the left ventricle; 3 cases also had right ventricular LGE. Median cardiac mass index was 155 g/m2 (Q1-Q3: 70–237; v.n. 31–79 g/m2). Overall, 17 (38.6%) patients died or required or heart transplant (HTx). Median age at the time of death or HTx was 17 years and 42 years in males and females, respectively (p=0.025 by the log-rank test)

Cognitive impairment, mainly described as learning disabilities, was diagnosed in 90.0% of males (18/20) and 79.2% (19/24) of females; intelligence quotient (IQ) measurement was reported in 8 patients (3 females, 5 males) and 7 of them showed IQ below the average. Symptomatic skeletal myopathy was present in 28 (63.3%) of patients, with a higher prevalence in males (85% vs. 45.8%; p<0.01). Retinopathy was reported in 14 (31.2%) patients and occurred equally in both genders (p=0.34).

Conclusions

DD causes significant cardiac morbidity with the need for transplant at a young age; in 25% of cases DD is due to a de novo mutation. While in males DD is more frequently multisystemic with a more rapid clinical deterioration, in females the clinical presentation is variable. However, the presence of severe cases in females warrant the clinicians to screen for DD in both sexes with clinical manifestations or positive family history

Acknowledgement/Funding

Rocket Pharmaceuticals

P1216Evaluation of alphavbeta3 integrin-targeted positron emission tomography and photoacoustic tracer for imaging of carotid plaque in apoE–/– mice

Background

Cardiovascular disease is the leading cause of death in the world. The majority of cardiovascular events result from the rupture of vulnerable atherosclerotic plaques, which are characterized by high and active macrophage content. The integrin αVβ3 is expressed by activated macrophages and endothelial cells in atherosclerotic lesions and thus is a marker of high-risk plaques. Therefore, 89Zr-RGD-melanin nanoparticle (MNP) positron emission tomography (PET)/photoacoustic imaging (PAI) imaging of αVβ3 expression in plaques might provide a novel noninvasive biomarker of plaque vulnerability.

Purpose

In this study, the intrinsic photoacoustic signals and the native strong chelating properties with metal ions of MNP, positron-emitting metal ions 89Zr and αVβ3 integrins targeting ability of cyclic c (RGDfC) peptide was employed to construct an efficient nanoplatform. And we evaluated the feasibility of 89Zr-RGD-MNP PET/PAI of αVβ3 expression in vivo and in vitro.

Methods

We conjugated αVβ3 integrins, cyclic c (RGDfC) peptide, to MNP and chelated the long-lived positron-emitting nuclide 89Zr. The bio-stability and targeting action was detected in macrophages. And the PET/PAI imaging was performed in apoE−/− mice with partial carotid ligation leading to atherosclerosis. In PET imaging, tracer uptake was measured in the stenotic areas of the carotid arteries, as well as on the contralateral side at different time points in vivo. In PAI, photoacoustic signal was measured in the atherosclerosis of the carotid arteries in vivo. Melanin staining and immunohistochemistry of αVβ3 expression were detected in atherosclerosis of the carotid arteries.

Results

89Zr-RGD-MNP showed excellent bio-stability and targeting action. PET imaging showed specific tracer accumulation at plaques in the left carotid artery, confirmed by competitive receptor blocking studies and the contrast in the right carotid artery. In the biodistribution studies, the left carotid (5.29%±0.78%) showed higher uptake than the right carotid (2.11%±1.55%). PAI showed the PA signal in the surgery group (452±85 a.u.) were stronger than the control (156±45 a.u.) and blocking group (254±66 a.u). The result was consistent with PET imaging and the presence of nanoparticles, as indicated by pathological examinations. These results presented good in vivo multimodality imaging (PET/PAI) properties.

Conclusions

We have developed 89Zr-labeled atherosclerotic plaques imaging agents based on the natural melanin nanoparticle. 89Zr-RGD-MNP demonstrates specific tracer accumulation in mice atherosclerotic carotid plaques. In this model, its uptake was associated with αVβ3 expression. 89Zr-RGD-MNP is a potential tracer for noninvasive imaging in atherosclerosis.

Acknowledgement/Funding

National Natural Science Foundation of China 81770452, 81470401

Electrooxidative and Regioselective C-H Azolation of Phenol and Aniline Derivatives

A general and practical protocol was developed for the regioselective C-H azolation of phenol and aniline derivatives by electrooxidative cross-coupling. The reaction occurs under metal-, oxidant-, and reagent-free conditions, allowing access to a wide variety of synthetically useful heteroarene derivatives. The reaction also tolerates a broad range of functional groups and is amenable to gram-scale synthesis. Finally, a preliminary mechanistic study indicated that a radical-radical-combination pathway might be involved in the coupling reaction.

Plasma cell-free DNA integrity plus circulating tumor cells: a potential biomarker of no distant metastasis breast cancer

Cell-free DNA integrity (cfDI) is a promising diagnostic and prognostic biomarker in breast cancer. However, no specific study has evaluated the diagnostic ability of cfDI in patients with no distant metastasis breast cancer (no-MBC) and benign breast tumor (BBT) to date. We assessed the plasma cfDI of 84 patients with no-MBC and 30 patients with BBT using quantitative PCR and compared it with circulating tumor cells (CTCs) and carbohydrate antigen 153 (CA153). The no-MBC group had significantly lower mean cfDI (0.58) than the BBT group (0.74, p = 0.004). Subgroup analysis showed that decreased cfDI seem to be associated with risk factors such as age 14% (mean cfDI = 0.57), tumor size > 2 cm (mean cfDI = 0.58), and positive lymph node status (mean cfDI = 0.56), but had no statistical significance. McNemar's test suggested that cfDI had stronger diagnostic power than CTCs, cfDNA concentration, or CA153 (p < 0.001). Spearman's rho showed that the correlation coefficient between cfDI and CTCs was 0.278 (p = 0.04) in the no-MBC group. Receiver operating characteristic curve analysis also suggested that cfDI was superior to CTCs or CA153. Combined with CTCs, cfDI reduced the false positive rate from 50% to 10.71% and increased the area under the curve value from 0.66 to 0.68. Our results suggest that cfDI is a potential diagnostic biomarker of no-MBC. Using cfDI and CTCs as a combined diagnostic tool for no-MBC could improve diagnostic sensitivity and specificity but more samples will be needed.

Aβ1-42 increases the expression of neural KATP subunits Kir6.2/SUR1 via the NF-κB, p38 MAPK and PKC signal pathways in rat primary cholinergic neurons

ATP-sensitive potassium channels (KATP) may mediate a potential neuroprotective role in Alzheimer's disease (AD). Given that exposure to Aβ1-42 in cultured primary cholinergic neurons for 72 h significantly upregulates the expression of KATP subunits Kir6.2/SUR1, we aim to study the underlying signal transduction mechanisms that are involved in Aβ_1-42-induced upregulation of KATP subunits Kir6.2/SUR1. In the present study, we first identified the primary cultured rat cortical and hippocampal neurons using immunocytochemistry. 0.5 μM NF-κB inhibitor SN-50, 2 μM p38MAPK inhibitor SB203580 or 2 μM PKC inhibitor Chelerythrine chloride (CTC) were then added in three separate groups, followed by 2 μM Aβ_1-42 30 min later in all 3 groups. Western Blot was performed 72 h later to detect the expression of KATP subunits Kir6.2/SUR1. We found that Aβ_1-42 significantly increased the level of KATP subunits Kir6.2/SUR1 expression at 72 h when compared with the control group ( p < 0.05). However, when compared with the Aβ_1-42 group, the level of KATP subunits Kir6.2/SUR1 expression at 72 h significantly decreased in the SN50 + Aβ_1-42 group, SB203580 + Aβ_1-42 group, and the CTC + Aβ_1-42 group ( p < 0.05). Our findings suggest that the NF-κB, p38 MAPK, and PKC signal pathways are partially involved in the upregulation of KATP subunits Kir6.2/SUR1 expression induced by Aβ_1-42 cytotoxicity in neurons, which supports a potential theoretical basis of targeting these signal pathways in the treatment of AD.

Microwave ablation combined with doxorubicin enhances cell death via promoting reactive oxygen species generation in breast cancer cells

PURPOSE

To evaluate the mechanism for enhancing cell death induced by microwave ablation (MWA) combined with doxorubicin treatment in breast cancer cells.

MATERIALS AND METHODS

Different temperatures of heat treatment were used to mimic the tumor affected by sublethal heat during MWA in vitro. Breast cancer cells were treated at 43°C and 45°C, with or without doxorubicin. Cell viability, apoptosis, and intracellular reactive oxygen species (ROS) were evaluated in MDA-MB-231 and SUM-1315 cells. Nude mice breast cancer models were randomly divided into control, MWA, doxorubicin, and combined treatment groups. Tumor apoptosis and DNA damage were evaluated in these groups.

RESULTS

The combined group had lower cell viability than the heat or doxorubicin group (all P<0.05), and enhanced apoptosis rate was observed in the combined group compared to others (all P<0.01) in MDA-MB-231 and SUM-1315. Increased capase3 (all P<0.01) and decreased Bcl-Xl (all P<0.01) were detected after combined therapy compared to single treated group in vitro. The raisedCaspase3 and DNA damage marker histone H2A.X induced by combined treatment were also approved in the nude mice models. Combined treatment promoted ROS generation compared to doxorubicin or MWA treatment (all P < 0.01). NF-κB expression in the combined group was higher than that of the single treatment group (all P<0.05). N-acetylcysteine (NAC), a ROS scavenger, partly restrained the combined treatment induced cell proliferation inhibition, Caspase3 and NF-κB compared to doxorubicin treatment (all P<0.05).

CONCLUSION

MWA combined with doxorubicin promote cell death via ROS induced cell apoptosis and DNA damage. Increasing ROS has potential for improving the efficiency of combined treatment.