P13.15 Pre-clinical trial of T601 oncolytic virus for high grade glima via intra-tumoral injection

BACKGROUND

An effective therapeutic method still hasn’t been devised for lethal high grade glioma. Thus, a method with high anti-tumoral efficiency, tumoral targeting, and acceptable side effect needs to be designed. Oncolytic virotherapy which can specifically lyse tumor cells via mass replication and deleting nucleotide metabolism related gene, like TK, required in viral replication and overexpressed in tumor cells, provides hope for patients. However, the virus only contained TK deletion is unable to show sufficient specificity of anti-tumoral response in tumor cells. Here, the adapted strain of vaccinia virus with high tumoral specificity due to TK and RR deletion and FUC1 insertion, named T601, is chosen in this project. In clinical application, intra-tumoral injection showed improved anti-tumoral efficiency and acceptable side effect. However, intra-tumoral viral injection in orthotropic glioma model is rare. In this project, various biosafety and antitumoral efficiency parameter would be tested for confirming the biosafety and reliability of intra-tumoral T601 viral injection for future clinical trials.

MATERIAL AND METHODS

For measuring the IC50 of T601, 10 different amounts of virus was tested in vitro via calculating cell viability with CCK-8(cell counting kit-8). For measuring the further antitumoral response of FCU1, different concentration of the 5-FC was added into the medium with IC50 viral amount. To ensure the biosafety of T601, MTD (maximum tolerance dose) was measured. Based on the MTD result, for evaluating the anti-tumoral efficiency, 106 pfu,105 pfu,104 pfu of virus was intra-tumoral injected in orthotopic GBM bearing mice. Tumor size was measured once a week through in vivo bioimaging system.

RESULTS

0.022 MOI, the IC50 of T601, showed high cytotoxicity of T601. Moreover, the significantly decreased cell viability under the combined treatment of 5-FC and 0.22MOI T601 showed intact anti-tumoral function. In MTD assay, except for 107 group, no significant weight loss was found. However, in 107 pfu group, mean body weight decreased around 10% and animal fatality happened on day 9. According to the MTD result, certain amount of virus was intra-tumorally injected. In all treatment group, the tumor size was significantly shrined. At the same time, the survival rate of mice under viral treatment was significantly extended.

CONCLUSION

In summary, T601 exhibited efficient anti-tumoral function and acceptable side effect. T601 treatment prolonged the survival period of GBM mice with acceptable neurotoxicity, demonstrating that T601 contains necessary criterial for intra-tumoral injection. Ultimately, this project provided basic reference information of dose for future clinical trial.

The E3 ubiquitin ligase Itch limits the progression of post-traumatic osteoarthritis in mice by inhibiting macrophage polarization

OBJECTIVE

Osteoarthritis (OA) is characterized by articular cartilage loss, associated with synovial inflammation. We recently reported increased pro-inflammatory macrophages in murine post-traumatic OA (PTOA) joints, and blockade of the ubiquitin-proteasome system alleviates PTOA progression. However, the mechanisms whereby protein ubiquitination influences PTOA pathology are not well studied. We hypothesized that loss of the negative regulator of inflammation, E3 ligase Itch, in macrophages contributes to joint OA tissue damage by promoting pro-inflammatory polarization of macrophages.

METHODS

Mice deficient Itch in macrophages (MΔItch) were generated by crossing Itchfl/fl mice with LysM-Cre mice. PTOA surgery was performed on global Itch knockout, Itch-/-, mice and MΔItch mice. Joint tissue damage and synovial macrophages were examined. Itch-/- cells were treated with IL-1 and pro-inflammatory polarization was determined. Expression of Itch protein and mRNA in PTOA synovium were assessed at different time points post PTOA.

RESULTS

Similar to Itch-/- mice, MΔItch mice developed more severe joint damage than control mice following PTOA surgery (mean difference of OARSI score: 1.17 (95% CI 0.31-2.03) between MΔItch and Itchfl/fl mice), accompanied by increased the inflammatory macrophage infiltration in the synovium (mean difference of % F4/80 + CD86 + CD36-inflammatory macrophages: 14.81 (95% CI 8.90-20.73) between MΔItch and Itchfl/fl mice). Itch-/- macrophages exerted pro-inflammatory phenotype in response to IL-1β treatment. Itch protein, but not mRNA levels decreased during PTOA progression.

CONCLUSION

The negative regulator of inflammation, Itch, limits PTOA progression by inhibiting macrophage pro-inflammatory polarization. Itch protein degradation may contribute to PTOA pathology.

LncRNA NR2F1-AS1 promotes proliferation and metastasis of ESCC cells via regulating EMT

OBJECTIVE

The aim of this study was to explore the expression of long non-coding ribonucleic acid (lncRNA) nuclear receptor subfamily 2 group F member 1-antisense RNA 1 (NR2F1-AS1) in esophageal squamous cell carcinoma (ESCC) tissues and cells and to investigate its effects on ESCC proliferation and metastasis.

PATIENTS AND METHODS

The expression level of NR2F1-AS1 in 51 pairs of ESCC tissues and corresponding adjacent tissues was detected via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). Meanwhile, NR2F1-AS1 expression in ESCC cells was measured via qRT-PCR as well. Subsequently, specific interference sequences of NR2F1-AS1 were designed, synthesized, and transiently transfected into ESCC cells. 48 h later, qRT-PCR assay was performed to detect the interference efficiency. The effects of small interfering (si)-NR2F1-AS1 on the proliferation of ESCC cells were determined through cell counting kit-8 (CCK-8) and colony formation assay. Wound healing and transwell assays were conducted to investigate the influences of si-NR2F1-AS1 on the migration and invasion of ESCC cells. Additionally, the changes in the expressions of epithelial-mesenchymal transition (EMT) molecular markers were detected by Western blotting.

RESULTS

QRT-PCR assay revealed that the expression level of NR2F1-AS1 was significantly up-regulated in 42 of 51 cases of ESCC tissues (42/51, 82.4%). Compared with esophageal mucosal epithelial HET-1A cells, NR2FA-AS1 was highly expressed in ESCC cells. CCK-8 and colony formation assay indicated that the proliferation of ESCC cells decreased remarkably after interference in NR2F1-AS1 expression. The results of wound healing and transwell assays showed that the migration and metastasis of cells were significantly lower in si-NR2F1-AS1 group than those in si-NC group. Western blotting demonstrated that the expressions of EMT molecular markers were changed after interfering with NR2F1-AS1 expression.

CONCLUSIONS

NR2F1-AS1 was highly expressed in ESCC tissues and cells. Furthermore, high expression of NR2F1-AS1 promoted the proliferation and metastasis of ESCC cells by modulating EMT.

A single nucleotide distinguishes the SARS-CoV-2 in the Wuhan outbreak in December 2019 from that in Beijing-Xinfadi in June 2020, China

Two major locally transmitted outbreaks of coronavirus disease 2019 occurred in China, one in Wuhan from December 2019 to April 2020, another in Beijing-Xinfadi in June 2020. Severe acute respiratory syndrome coronavirus 2 isolated from these two outbreaks can be distinguished by a conserved pyrimidine nucleotide located at nucleotide position 241 in the 5′-untranslated region of the virus genome.

Predictors of plaque erosion in current smokers and non-current smokers presented with ST-segment elevation myocardial infarction: an optical coherence tomography study

Background

Plaque erosion with subsequent coronary thrombosis is considered as an important cause of ST-segment elevation myocardial infarction (STEMI). Smoking is a major risk factor for acute coronary thrombosis. However, the relationship between current smoking status and plaque erosion has not been systematically investigated.

Purpose

The present study aimed to investigate predictors of plaque erosion in current smokers and non-current smokers with STEMI by using optical coherence tomography (OCT).

Methods

Between January 2015 to December 2017, a total of 1313 STEMI patients underwent pre-intervention OCT of culprit lesion were enrolled and divided into two groups based on current smoking status: current smoking group (n=713) and non-current smoking group (n=600). Using established criteria, quantitative and qualitative underlying plaque characteristics were assessed by OCT. Clinical, angiographic and OCT characteristics of all enrolled patients were recorded. Univariable and multivariable logistic regression analyses were used to identify predictors of plaque erosion in two groups.

Results

Plaque erosion were found in 30.9% (220/713) culprit lesions in current smoking group and 20.8% (125/600) of those in non-current smoking group detected by OCT. In multivariate regression analysis, the predictors that strongly related to plaque erosion in the current smoking group were nearby bifurcation (OR: 4.84; 95% CI:2.38–9.87; p<0.001); the minimum fiber cap thickness (FCT, OR:1.05; 95% CI:1.03–1.08; p<0.001); thin-cap fibroatheroma (TCFA, OR: 0.22; 95% CI: 0.07–0.67; p=0.007) and lipid core length (OR: 0.91; 95% CI: 0.84–0.97; p=0.007). The predictors in the non-current smoking group were nearby bifurcation (OR: 4.84; 95% CI: 2.38–9.87; p=0.006); the minimal FCT (OR: 1.09; 95% CI: 1.06–1.13; p<0.001); multi-vessel disease (MVD, OR: 0.43; 95% CI: 0.19–0.97; p=0.042) and dyslipidemia (OR: 0.34; 95% CI: 0.14–0.84; p=0.020).

Conclusions

Predictors of plaque erosion causing STEMI onset are different between current smokers and non-current smoker, with nearby bifurcation and thicker minimal FCT both predicting plaque erosion in two groups of patients.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Key Research and Development Program of China, National Natural Science Foundation of China.

Morphological characteristics of plaque erosion with noncritical coronary stenosis: an optical coherence tomography study

Background

Plaque erosion is a frequent and important mechanism of acute coronary thrombosis only secondary to plaque rupture. Recent studies suggested plaque erosion with noncritical stenosis could be treated conservatively that distinct from those with critical stenosis. However, characteristics of plaque erosions with different coronary stenosis remain unknown.

Purpose

The present study aimed to investigate morphological features of plaque erosions with different coronary stenosis using optical coherence tomography (OCT).

Methods

Consecutive ST-segment elevated myocardial infarction (STEMI) patients with OCT images of culprit lesion between August 2014 and December 2017 were enrolled and 348 cases presented with plaque erosion identified by OCT. Based on the severity of lumen area stenosis [calculated by (1-minimal lumen area/reference lumen area) * 100%], all culprit plaque erosions were divided into three groups: Group A (area stenosis<50%, n=50, 14.4%); Group B (50%≤area stenosis<75%, n=146, 42.0%); Group C (area stenosis≥75%, n=152, 43.7%). Clinical characteristics, lesion features detected by coronary angiography and OCT were compared among three groups.

Results

Of all 348 STEMI patients with plaque erosions, patients in Group A were youngest (p=0.008) and had the lowest frequency of hypertension (p=0.029) as compared with those in Group B and C. Angiographic analysis showed 72.0% of plaque erosions in Group A located in LAD, while 67.8% in Group B and 53.9% in Group C (p=0.039). OCT findings (Figure 1-A) showed the prevalence of fibrous plaque was significantly highest in Group A than those in Group B and C (82.0% vs. 54.8% vs. 34.9%, p<0.001), whereas lipid rich plaque was most frequent in Group C (16.0% vs. 43.8% vs. 62.5%, p<0.001). The prevalence of macrophage (p<0.001), microvessel (p=0.009) and cholesterol crystals (p<0.001) increased gradually from plaque erosion with lumen area stenosis <50% to 50–75% to ≥75%. Notably, compared with Group B and C, nearby bifurcation was most common in Group A (72.0% vs. 67.1% vs. 55.3%, p=0.036). Multivariable regression analyses (Figure 1-B) showed fibrous plaque and nearby bifurcation were independently associated with plaque erosion with noncritical stenosis (area stenosis<75%).

Conclusion

56.3% plaque erosion in STEMI patients presented with noncritical stenosis, having distinct morphological features from erosion with critical stenosis. Fibrous plaque and nearby bifurcation were independently associated with the presence of noncritically stenotic plaque erosion, remaining a desire to tailor treatment therapy to individual patients.

Figure 1

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Key R&D Program of China

Literature mapping: association of microscopic skin microflora and biomarkers with macroscopic skin health

Associations between skin microbes or biomarkers and pathological conditions have been reported in the literature. However, there is a lack of clarity on the interaction between the coexistence of common skin microbes with skin physiology and subsequent development of clinical symptoms, and the role of biomarkers in mediating these changes before the development of skin disease. In this review, we aim to identify areas in which extensive research for the studied factors has already been conducted, and which research areas are under-represented. The SciFinder database was searched for articles containing key words including specific skin microbes, biomarkers, skin physiology and diseases from the beginning of the SciFinder data record to 26 April 2016, and we included an additional relevant recent publication from our group. Among the 8000 + articles selected, the frequency of keyword pairs between two roles [microscopic markers (microflora or biomarkers) and reactions (skin physiology or clinical symptoms, or skin disease)] was investigated. Associated research between the individual factors such as skin microflora or biomarkers (chosen based on our earlier publication) and specific biophysical parameters, symptoms or skin disease was identified. The present research heatmap emphasizes the significance of a structured review of research on concerned factor associations to identify early/subclinical clues that can be used to prevent progression to overt skin disease with the help of precise skin care or early intervention, as indicated by skin microflora, biomarkers and an interactive skin biophysics profile. The findings provide a novel approach to explore such associations and may guide future research directed towards predicting disease from early/subclinical symptoms.

Radiomics: A primer for the radiation oncologist

PURPOSE

Radiomics are a set of methods used to leverage medical imaging and extract quantitative features that can characterize a patient's phenotype. All modalities can be used with several different software packages. Specific informatics methods can then be used to create meaningful predictive models. In this review, we will explain the major steps of a radiomics analysis pipeline and then present the studies published in the context of radiation therapy.

METHODS

A literature review was performed on Medline using the search engine PubMed. The search strategy included the search terms "radiotherapy", "radiation oncology" and "radiomics". The search was conducted in July 2019 and reference lists of selected articles were hand searched for relevance to this review.

RESULTS

A typical radiomics workflow always includes five steps: imaging and segmenting, data curation and preparation, feature extraction, exploration and selection and finally modeling. In radiation oncology, radiomics studies have been published to explore different clinical outcome in lung (n=5), head and neck (n=5), esophageal (n=3), rectal (n=3), pancreatic (n=2) cancer and brain metastases (n=2). The quality of these retrospective studies is heterogeneous and their results have not been translated to the clinic.

CONCLUSION

Radiomics has a great potential to predict clinical outcome and better personalize treatment. But the field is still young and constantly evolving. Improvement in bias reduction techniques and multicenter studies will hopefully allow more robust and generalizable models.

Augmented decision-making for acral lentiginous melanoma detection using deep convolutional neural networks

BACKGROUND

Several studies have achieved high-level performance of melanoma detection using convolutional neural networks (CNNs). However, few have described the extent to which the implementation of CNNs improves the diagnostic performance of the physicians.

OBJECTIVE

This study is aimed at developing a CNN for detecting acral lentiginous melanoma (ALM) and investigating whether its implementation can improve the initial decision for ALM detection made by the physicians.

METHODS

A CNN was trained using 1072 dermoscopic images of acral benign nevi, ALM and intermediate tumours. To investigate whether the implementation of CNN can improve the initial decision for ALM detection, 60 physicians completed a three-stage survey. In Stage I, they were asked for their decisions solely on the basis of dermoscopic images provided to them. In Stage II, they were also provided with clinical information. In Stage III, they were provided with the additional diagnosis and probability predicted by the CNN.

RESULTS

The accuracy of ALM detection in the participants was 74.7% (95% confidence interval [CI], 72.6-76.8%) in Stage I and 79.0% (95% CI, 76.7-81.2%) in Stage II. In Stage III, it was 86.9% (95% CI, 85.3-88.4%), which exceeds the accuracy delivered in Stage I by 12.2%p (95% CI, 10.1-14.3%p) and Stage II by 7.9%p (95% CI, 6.0-9.9%p). Moreover, the concordance between the participants considerably increased (Fleiss-κ of 0.436 [95% CI, 0.437-0.573] in Stage I, 0.506 [95% CI, 0.621-0.749] in Stage II and 0.684 [95% CI, 0.621-0.749] in Stage III).

CONCLUSIONS

Augmented decision-making improved the performance of and concordance between the clinical decisions of a diverse group of experts. This study demonstrates the potential use of CNNs as an adjoining, decision-supporting system for physicians' decisions.

RNA-splicing factor SART3 regulates translesion DNA synthesis

Translesion DNA synthesis (TLS) is one mode of DNA damage tolerance that uses specialized DNA polymerases to replicate damaged DNA. DNA polymerase η (Polη) is well known to facilitate TLS across ultraviolet (UV) irradiation and mutations in POLH are implicated in skin carcinogenesis. However, the basis for recruitment of Polη to stalled replication forks is not completely understood. In this study, we used an affinity purification approach to isolate a Polη-containing complex and have identified SART3, a pre-mRNA splicing factor, as a critical regulator to modulate the recruitment of Polη and its partner RAD18 after UV exposure. We show that SART3 interacts with Polη and RAD18 via its C-terminus. Moreover, SART3 can form homodimers to promote the Polη/RAD18 interaction and PCNA monoubiquitination, a key event in TLS. Depletion of SART3 also impairs UV-induced single-stranded DNA (ssDNA) generation and RPA focus formation, resulting in an impaired Polη recruitment and a higher mutation frequency and hypersensitivity after UV treatment. Notably, we found that several SART3 missense mutations in cancer samples lessen its stimulatory effect on PCNA monoubiquitination. Collectively, our findings establish SART3 as a novel Polη/RAD18 association regulator that protects cells from UV-induced DNA damage, which functions in a RNA binding-independent fashion.