POS0647 EFFICACY, SAFETY AND CHARACTERISTICS OF IGURATIMOD-BASED THERAPY IN THE TREATMENT OF UA, ERA AND RA PATIENTS FOR 24 WEEKS: A PROSPECTIVE COHORT STUDY

Background:

Experts emphasize early diagnosis and treatment in RA, but the widely used diagnostic criterias fail to meet the accurate judgment of early rheumatoid arthritis. In 2012, Professor Zhanguo Li took the lead in establishing ERA “Chinese standard”, and its sensitivity and accuracy have been recognized by peers. However, the optimal first-line treatment of patients (pts) with undifferentiated arthritis (UA), early rheumatoid arthritis (ERA), and rheumatoid arthritis (RA) are yet to be established.

Objectives:

To evaluate the efficacy and safety of Iguratimod-based (IGU-based) Strategy in the above three types of pts, and to explore the characteristics of the effects of IGU monotherapy and combined treatment.

Methods:

This prospective cohort study (ClinicalTrials.gov Identifier NCT01548001) was conducted in China. In this phase 4 study pts with RA (ACR 1987 criteria[1]), ERA (not match ACR 1987 criteria[1] but match ACR/EULAR 2010 criteria[2] or 2014 ERA criteria[3]), UA (not match classification criteria for ERA and RA but imaging suggests synovitis) were recruited. We applied different treatments according to the patient’s disease activity at baseline, including IGU monotherapy and combination therapies with methotrexate, hydroxychloroquine, and prednisone. Specifically, pts with LDA and fewer poor prognostic factors were entered the IGU monotherapy group (25 mg bid), and pts with high disease activity were assigned to combination groups. A Chi-square test was applied for comparison. The primary outcomes were the proportion of pts in remission (REM)or low disease activity (LDA) that is DAS28-ESR<2.6 or 3.2 at 24 weeks, as well as the proportion of pts, achieved ACR20, Boolean remission, and good or moderate EULAR response (G+M).

Results:

A total of 313 pts (26 pts with UA, 59 pts with ERA, and 228 pts with RA) were included in this study. Of these, 227/313 (72.5%) pts completed the 24-week follow-up. The results showed that 115/227 (50.7%), 174/227 (76.7%), 77/227 (33.9%), 179/227 (78.9%) pts achieved DAS28-ESR defined REM and LDA, ACR20, Boolean remission, G+M response, respectively. All parameters continued to decrease in all pts after treatment (Fig 1).

Compared with baseline, the three highest decline indexes of disease activity at week 24 were SW28, CDAI, and T28, with an average decline rate of 73.8%, 61.4%, 58.7%, respectively. Results were similar in three cohorts.

We performed a stratified analysis of which IGU treatment should be used in different cohorts. The study found that the proportion of pts with UA and ERA who used IGU monotherapy were significantly higher than those in the RA cohort. While the proportion of triple and quadruple combined use of IGU in RA pts was significantly higher than that of ERA and UA at baseline and whole-course (Fig 2).

A total of 81/313 (25.8%) pts in this study had adverse events (AE) with no serious adverse events. The main adverse events were infection(25/313, 7.99%), gastrointestinal disorders(13/313, 4.15%), liver dysfunction(12/313, 3.83%) which were lower than 259/2666 (9.71%) in the previous Japanese phase IV study[4].

The most common reasons of lost follow-up were: 1) discontinued after remission 25/86 (29.1%); 2) lost 22/86 (25.6%); 3) drug ineffective 19/86 (22.1%).

Conclusion:

Both IGU-based monotherapy and combined therapies are tolerant and effective for treating UA, ERA, and RA, while the decline in joint symptoms was most significant. Overall, IGU combination treatments were most used in RA pts, while monotherapy was predominant in ERA and UA pts.

References:

[1]Levin RW, et al. Scand J Rheumatol 1996, 25(5):277-281.

[2]Kay J, et al. Rheumatology 2012, 51(Suppl 6):vi5-9.

[3]Zhao J, et al. Clin Exp Rheumatol 2014, 32(5):667-673.

[4]Mimori T, et al. Mod Rheumatol 2019, 29(2):314-323.

Disclosure of Interests:

None declared

Association of RYR2 Mutation With Tumor Mutation Burden, Prognosis, and Antitumor Immunity in Patients With Esophageal Adenocarcinoma

Background: Esophageal adenocarcinoma (EAC) remains a leading cause of cancer-related deaths worldwide and demonstrates a predominant rising incidence in Western countries. Recently, immunotherapy has dramatically changed the landscape of treatment for many advanced cancers, with the benefit in EAC thus far been limited to a small fraction of patients.

Methods: Using somatic mutation data of The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium, we delineated the somatic mutation landscape of EAC patients from US and England. Based on the expression data of TCGA cohort, multiple bioinformatics algorithms were utilized to perform function annotation, immune cell infiltration analysis, and immunotherapy response assessment.

Results: We found that RYR2 was a common frequently mutated gene in both cohorts, and patients with RYR2 mutation suggested higher tumor mutation burden (TMB), better prognosis, and superior expression of immune checkpoints. Moreover, RYR2 mutation upregulated the signaling pathways implicated in immune response and enhanced antitumor immunity in EAC. Multiple bioinformatics algorithms for assessing immunotherapy response demonstrated that patients with RYR2 mutation might benefit more from immunotherapy. In order to provide additional reference for antitumor therapy of different RYR2 status, we identified nine latent antitumor drugs associated with RYR2 status in EAC.

Conclusion: This study reveals a novel gene whose mutation could be served as a potential biomarker for prognosis, TMB, and immunotherapy of EAC patients.

A wide-ranging Pseudomonas aeruginosa PeptideAtlas build: A useful proteomic resource for a versatile pathogen

Pseudomonas aeruginosa is an important opportunistic human pathogen with high prevalence in nosocomial infections. This microorganism is a good model for understanding biological processes such as the quorum-sensing response, the metabolic integration of virulence, the mechanisms of global regulation of bacterial physiology, and the evolution of antibiotic resistance. Till now, P. aeruginosa proteomic data, although available in several on-line repositories, were dispersed and difficult to access. In the present work, proteomes of the PAO1 strain grown under different conditions and from diverse cellular compartments have been joined to build the Pseudomonas PeptideAtlas. This resource is a comprehensive mass spectrometry-derived peptide and inferred protein database with 71.3% coverage of the total predicted proteome of P. aeruginosa PAO1, the highest coverage among bacterial PeptideAtlas datasets. The proteins included cover 89% of metabolic proteins, 72% of proteins involved in genetic information processing, 83% of proteins responsible for environmental information processing, more than 88% of the ones related to quorum sensing and biofilm formation, and 89% of proteins responsible for antimicrobial resistance. It exemplifies a necessary tool for targeted proteomics studies, system-wide observations, and cross-species observational studies. The manuscript describes the building of the PeptideAtlas and the contribution of the different proteomic data used. SIGNIFICANCE: Pseudomonas aeruginosa is among the most versatile human bacterial pathogens. Studies of its proteome are very important as they can reveal virulence factors and mechanisms of antibiotic resistance. The construction of a proteomic resource such as the PeptideAtlas enables targeted proteomics studies, system-wide observations, and cross-species observational studies.

LINC01272/miR-876/ITGB2 axis facilitates the metastasis of colorectal cancer via epithelial-mesenchymal transition

Background: At the time of diagnosis, colorectal cancer (CRC) patients are usually in an advanced stage of disease, which is accompanied by metastasis. Long noncoding RNAs (lncRNAs) play critical regulatory roles in cancer biology. However, the contributions of lncRNA LINC01272 to CRC remain elusive. Methods: Bioinformatics and the survminer R package were used to predict intermolecular correlations and prognostic indicators. Quantitative real-time PCR was used to examine molecular expression. In vitro experiments, including migration assays, invasion assays, and wound healing assays, were used to investigate the effects of LINC01272, ITGB2 and miR-876 on CRC cell migration and invasion abilities. Furthermore, a dual-luciferase reporter gene assay was performed to explore the potential mechanism by which LINC01272 contributes to CRC. Results: We found that LINC01272 was highly expressed in multiple cancers and closely related to core epithelial-mesenchymal transition (EMT) factors and that high levels of LINC01272 are associated with a poor prognosis in CRC patients. qRT-PCR revealed that LINC01272 was highly expressed and negatively associated with miR-876 in CRC. Additionally, LINC01272 or ITGB2 silencing reduced, while miR-876 overexpression promoted, the invasiveness and metastatic capacity of CRC cells in vitro. Moreover, LINC01272 potentially targeted miR-876, and miR-876 potentially targeted ITGB2. Conclusion: LINC01272 was highly expressed in CRC and predicted a poor prognosis. LINC01272 promoted EMT and metastasis by regulating miR-876/ITGB2 to act as an oncogene in CRC. LINC01272 may be a promising prognostic biomarker and therapeutic target for the treatment of CRC patients in the future.

Genomic Alteration Characterization in Colorectal Cancer Identifies a Prognostic and Metastasis Biomarker: FAM83A|IDO1

Genomic alterations constitute crucial elements of colorectal cancer (CRC). However, a comprehensive understanding of CRC genomic alterations from a global perspective is lacking. In this study, a total of 2,778 patients in 15 public datasets were enrolled. Tissues and clinical information of 30 patients were also collected. We successfully identified two distinct mutation signature clusters (MSC) featured by massive mutations and dominant somatic copy number alterations (SCNA), respectively. MSC-1 was associated with defective DNA mismatch repair, exhibiting more frequent mutations such as ATM, BRAF, and SMAD4. The mutational co-occurrences of BRAF-HMCN and DNAH17-MDN1 as well as the methylation silence event of MLH-1 were only found in MSC-1. MSC-2 was linked to the carcinogenic process of age and tobacco chewing habit, exhibiting dominant SCNA such as MYC (8q24.21) and PTEN (10q23.31) deletion as well as CCND3 (6p21.1) and ERBB2 (17q12) amplification. MSC-1 displayed higher immunogenicity and immune infiltration. MSC-2 had better prognosis and significant stromal activation. Based on the two subtypes, we identified and validated the expression relationship of FAM83A and IDO1 as a robust biomarker for prognosis and distant metastasis of CRC in 15 independent cohorts and qRT-PCR data from 30 samples. These results advance precise treatment and clinical management in CRC.

TTN/OBSCN 'Double-Hit' predicts favourable prognosis, 'immune-hot' subtype and potentially better immunotherapeutic efficacy in colorectal cancer

Colorectal cancer (CRC) remains a leading cause of cancer-related deaths worldwide. Although treatment strategies for solid tumours have been revolutionized by immunotherapy, only a small subset of CRC patients benefit. Using two-independent cohorts, we found the common frequently mutated genes TTN and OBSCN had the significant correlation with higher tumour mutation burden (TMB) and favourable overall survival. TTN and OBSCN also displayed significant commutation phenomenon. Therefore, based on the status of TTN and OBSCN, we stratified patients into 'Double-WT' phenotype, 'Single-Hit' phenotype and 'Double-Hit' phenotype. Importantly, the 'Double-Hit' phenotype had favourable prognosis, low malignant events propensity, and highest TMB, immune cells infiltration abundance, POLE mutation rate, microsatellite instability ratio, as well as immune checkpoints expression compared with the other two phenotypes. These results indicated that the 'Double-Hit' phenotype suggested 'immune-hot' tumours and potentially better immunotherapeutic efficacy. Bioinformatic algorithm assessment of immunotherapy responses also confirmed this conclusion, and the 'Double-Hit' phenotype was found to be a better predictor of immunotherapy than PD-L1, PD-1, CTLA-4, TMB and microsatellite status. This study revealed CRC patients with TTN/OBSCN 'Double-Hit' was significantly associated favourable prognosis, 'immune-hot' subtype and potentially better immunotherapeutic efficacy.

Roles of RNA Methylation on Tumor Immunity and Clinical Implications

RNA methylation is a kind of RNA modification that exists widely in eukaryotes and prokaryotes. RNA methylation occurs not only in mRNA but also in ncRNA. According to the different sites of methylation, RNA methylation includes m⁶A, m⁵C, m⁷G, and 2-O-methylation modifications. Modifications affect the splicing, nucleation, stability and immunogenicity of RNA. RNA methylation is involved in many physiological and pathological processes. In the immune system, especially for tumor immunity, RNA methylation affects the maturation and response function of immune cells. Through the influence of RNA immunogenicity and innate immune components, modifications regulate the innate immunity of the body. Some recent studies verified that RNA methylation can regulate tumor immunity, which also provides a new idea for the future of treating immunological diseases and tumor immunotherapy.

LINC01296/miR-141-3p/ZEB1-ZEB2 axis promotes tumor metastasis via enhancing epithelial-mesenchymal transition process

Purpose: Tumor metastasis seriously affects the survival of patients. In recent years, some studies confirmed that long non-coding RNA (lncRNA) played an essential role in tumor progression. A few studies reported that LINC01296 acted as an oncogenic regulator of cancer. However, its in-depth specific biological mechanism in tumor metastasis is still unknown.

Methods: Real-time quantitative PCR (qPCR) was performed to detect the expression of LINC01296 and miR-141-3p in NSCLC, CRC tissues and cell lines, and the dual luciferase report was used to evaluate the relationship between LINC01296, miR-141-3p and ZEB1/ZEB2 relationship. Western blot experiments are used to detect changes in protein levels. Transwell and wound healing measures migration and invasion capabilities.

Results: In this study, we used non-small cell lung cancer (NSCLC) and colorectal cancer (CRC) as the research objects, LINC01296 was found to be highly expressed in NSCLC and CRC tissues and positively related to poor prognosis. We also demonstrated LINC01296 regulated NSCLC and CRC invasion and metastasis by modulating epithelial-mesenchymal transition (EMT) by up-regulating ZEB1 and ZEB2. Consequently, LINC01296 acted as a sponge of miR-141-3p, which negatively regulates EMT process.

Conclusions: The report revealed a new mechanism by which LINC01296 regulates the EMT process through miR-141-3p/ZEB1-ZEB2 axis and affects cancer metastasis.

N6-methyladenosine-induced circ1662 promotes metastasis of colorectal cancer by accelerating YAP1 nuclear localization

Tumor metastasis is the leading cause of death in patients with colorectal cancer (CRC). Circular RNAs (circRNAs) have been shown to be involved in cancer progression. However, the regulatory mechanisms of circRNAs involved in CRC tumor metastasis are currently unknown.

Methods: High-throughput sequencing was performed on 6 pairs of CRC and adjacent normal tissues to identify the expression profiles of mRNA and circRNA. circ1662 was assessed by RNA-ISH and IHC of a tissue chip. The function of circ1662 in CRC was evaluated by knocking down or overexpressing circ1662. MeRIP-qPCR, RIP-qPCR, and RNA pull-down were performed to determine the relationship between METTL3, circ1662, and YAP1.

Results: A novel circRNA, circ1662, exhibited significantly higher expression in CRC tissues than paired normal tissues. High circ1662 expression was correlated with poor prognosis and tumor depth in patients with CRC. Functionally, circ1662 promoted CRC cell invasion and migration by controlling EMT in vitro and in vivo. Mechanistically, circ1662 directly bound to YAP1 and accelerated its nuclear accumulation to regulate the SMAD3 pathway. Additionally, circ1662 enhanced CRC invasion and migration depending on YAP1 and SMAD3. Interestingly, METTL3 induced circ1662 expression by binding its flanking sequences and installing m6A modifications. Clinically, circ1662 expression strongly correlated with METTL3 and YAP1 protein expression. Moreover, YAP1 expression was negatively correlated with SMAD3 expression.

Conclusions: METTL3-induced circ1662 promoted CRC cell invasion and migration by accelerating YAP1 nuclear transport. This result implies that circ1662 is a new prognostic and therapeutic marker for CRC metastasis.

Roles of circRNAs on tumor autophagy

Circular RNAs (circRNAs) are a type of special noncoding RNA. circRNAs are highly stable and are found mainly in the cytoplasm. Most circRNAs are conserved and usually exhibit tissue specificity and timing specificity. In addition to the regulation mode of competitive endogenous RNA (ceRNA), circRNAs can also bind to RNA-binding proteins (RBPs), regulate alternative splicing, encode proteins or polypeptides, and regulate the expression of parent genes affecting biological pathways in which coded proteins are involved. Autophagy is an important cellular mechanism that plays an essential role in normal cell physiological processes and in diseases, especially tumors. Studies reported that circRNAs have an important effect on autophagic processes. What are the detailed biological functions and mechanisms of circRNAs in autophagy? In this article, we summarize the relationship between circRNAs and autophagy and the regulatory function and mechanism (especially as microRNA [miRNA] sponges and binding to RBPs) of circRNAs in autophagy. In addition, we discuss the dysregulation and functional and clinical applications of autophagy-associated circRNAs in a variety of diseases. Autophagy-associated circRNAs have the potential to be essential biomarkers of diagnosis and treatment and to be beneficial to the research and development of targeted drugs for tumor or non-tumor diseases.

The STING-IRF3 pathway is involved in lipotoxic injury of pancreatic β cells in type 2 diabetes

Lipotoxic injury of pancreatic β cells is an important pathological feature in type 2 diabetes mellitus (T2DM). Stimulator of interferon genes (STING) can recognize its own DNA leaked into the cytoplasm from damaged mitochondria or nuclei of the host cell, thus activating its downstream factor interferon regulatory factor 3 (IRF3), causing inflammation and apoptosis. The STING-IRF3 signaling pathway is closely related to glycolipid metabolism, but its relationship with the lipotoxicity of pancreatic β cells has rarely been reported. Here, we investigated the role of the STING-IRF3 signaling pathway in lipotoxicity-induced inflammation, apoptosis, and dysfunction of pancreatic β cells. We examined the activation of STING and IRF3 in islets of db/db mice and identified the role of the STING-IRF3 signaling pathway in palmitic acid (PA)-induced lipotoxic injury of INS-1, a rat insulinoma cell line. STING and phosphorylated IRF3 including downstream interferon-β were upregulated in islets of db/db mice and PA-induced INS-1 cells. Gene silencing of STING or IRF3 ameliorated PA-induced INS-1 cell inflammation and apoptosis, and reversed impaired insulin synthesis. Additionally, PA induced downregulation of the phosphoinositide 3-kinase-AKT signaling pathway, and impaired high glucose-stimulated insulin secretion was reversed after knockdown of STING or IRF3. Our results suggest that activation of the STING-IRF3 pathway triggers inflammation and apoptosis of pancreatic β cells, leading to β-cell damage and dysfunction. Hence, inhibition of this signaling pathway may represent a novel approach for β-cell protection in T2DM.

MiR-103a-3p promotes tumour glycolysis in colorectal cancer via hippo/YAP1/HIF1A axis

Background

Glycolysis plays an essential role in the growth and metastasis of solid cancer and has received increasing attention in recent years. However, the complex regulatory mechanisms of tumour glycolysis remain elusive. This study aimed to explore the molecular effect and mechanism of the noncoding RNA miR-103a-3p on glycolysis in colorectal cancer (CRC).

Methods

We explored the effects of miR-103a-3p on glycolysis and the biological functions of CRC cells in vitro and in vivo. Furthermore, we investigated whether miR-103a-3p regulates HIF1A expression through the Hippo/YAP1 pathway, and evaluated the role of the miR-103a-3p-LATS2/SAV1-YAP1-HIF1A axis in promoting glycolysis and angiogenesis in CRC cells and contributed to invasion and metastasis of CRC cells.

Results

We found that miR-103a-3p was highly expressed in CRC tissues and cell lines compared with matched controls and the high expression of miR-103a-3p was associated with poor patient prognosis. Under hypoxic conditions, a high level of miR-103a-3p promoted the proliferation, invasion, migration, angiogenesis and glycolysis of CRC cells. Moreover, miR-103a-3p knockdown inhibited the growth, proliferation, and glycolysis of CRC cells and promoted the Hippo-YAP1 signalling pathway in nude mice in a xenograft model. Here, we demonstrated that miR-103a-3p could directly target LATS2 and SAV1. Subsequently, we verified that TEAD1, a transcriptional coactivator of Yes-associated protein 1 (YAP1), directly bound to the HIF1A promoter region and the YAP1 and TEAD1 proteins co-regulated the expression of HIF1A, thus promoting tumour glycolysis.

Conclusions

MiR-103a-3p, which is highly expressed in CRC cells, promotes HIF1A expression by targeting the core molecules LATS2 and SAV1 of the Hippo/YAP1 pathway, contributing to enhanced proliferation, invasion, migration, glycolysis and angiogenesis in CRC. Our study revealed the functional mechanisms of miR-103a-3p/YAP1/HIF1A axis in CRC glycolysis, which would provide potential intervention targets for molecular targeted therapy of CRC.