Hypoxia-induced exosomal circPDK1 promotes pancreatic cancer glycolysis via c-myc activation by modulating miR-628-3p/BPTF axis and degrading BIN1

Background

circRNA has been established to play a pivotal role in tumorigenesis development in a variety of cancers; nevertheless, the biological functions and molecular mechanisms of hypoxia-induced exosomal circRNAs in pancreatic cancer remain largely unknown.

Methods

Differentially expressed circRNAs in exosomes between hypoxic exosomes and normoxic exosomes in PC cells were verified by RNA sequencing. The expression of circPDK1 in PC tumors and PC patients was evaluated by qRT-PCR and ISH, and the biological functions of circPDK1 in PC were verified through a series of in vitro and in vivo experiments. Using Western blotting, Co-IP, RNA pull-down, ChIP, RIP, dual-luciferase assays, and rescue experiments, the underlying mechanism of circPDK1 was verified.

Results

CircPDK1 was highly abundant in PC tumor tissues and serum exosomes and was associated with poor survival. Exosomal circPDK1 significantly promoted PC cell proliferation, migration, and glycolysis both in vitro and in vivo. Mechanistically, circPDK1 could be activated by HIF1A at the transcriptional level and sponges miR-628-3p to activate the BPTF/c-myc axis. In addition, circPDK1 serves as a scaffold that enhances the interaction between UBE2O and BIN1, inducing the UBE2O-mediated degradation of BIN1.

Conclusions

We found that circPDK1 was activated by HIF1A at the transcriptional level by modulating the miR-628-3p/BPTF axis and degrading BIN1. Exosomal circPDK1 is a promising biomarker for PC diagnosis and prognosis and represents a potential therapeutic target for PC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13045-022-01348-7.

Long-term exposure to air pollution increases hip fracture incidence rate and related mortality: analysis of National Hip Fracture Database

To explore the association of air pollution and hip fracture and related mortality in the UK. The average levels of PM2.5, PM10, and NO2 exhibited a positive association with hip fracture and short-term mortality while O₃ did not. Our study highlights the association of air pollution and hip fracture.

INTRODUCTION

Until now, the influence of air pollution on bone mineral density and associated fractures has drawn little attention, and the consequences are controversial. To investigate the association between air pollution and hip fracture incidence and related short-term mortality.

METHODS

We constructed a cohort of all the National Hip Fracture Database beneficiaries (513,540 patients) in the UK from 2013 to 2018. Per year averages of PM_2.5, PM₁₀, O₃, NO₂, and SO₂ were estimated according to the person's residence. The incidence rate ratio with 95% confidence interval and all-cause mortality within 30-day post-fracture (ACM30D) rate ratios were estimated using generalized additive models.

RESULTS

The average levels of PM_2.5, PM₁₀, and NO₂ exhibited a positive association with the incidence rate of hip fracture (IHF) and ACM30D. Whereas, this association was negative for O₃ levels. Each increase of 5 μg per cubic meter in PM_2.5, PM₁₀, and NO₂ leads to 9.5%, 9.2%, and 4.1% higher hip fracture rate, respectively, and also 9.3%, 8.3%, and 2.9% higher ACM30D, respectively. When we restricted the analysis to low-level exposure of air pollutants, similar results were obtained.

CONCLUSION

Our study found a moderate, positive association between IHF, ACM30D, and the levels of specific air pollutants in the entire National Hip Fracture Database population. A reduction in the levels of PM_2.5, PM₁₀, and NO₂ may decrease the hip fracture incidence rate and associated short-term mortality in older adults. Our study highlights the influence of air pollution on hip fracture.

Torque response of seated human body to sinusoidal lateral and roll dual-axis vibration

The biodynamic response of 14 subjects to sinusoidal dual-axis vibration in lateral and roll directions is studied. The root mean square of human response is detected by measuring the torque at the seat pan. The effects of phase difference, magnitude, and frequency on the biodynamic responses are investigated. The consistency between human responses to dual-axis and single-axis is studied. With increasing phase difference, human response is found to reach the maximum when the vibrations are anti-phase and then decrease to the minimum when they are in-phase. Besides, the dominance of the lateral excitation is confirmed in the dual-axis vibration. Finally, the principle of equivalence between lateral-roll dual-axis vibration and roll single-axis vibration is established. With the equivalence method, the biodynamic characteristics of the human body to multi-axis vibration are expected to be measured and represented with a much simpler test and dynamic model. Practitioner summary: Proposed equivalence uses one index to evaluate the compound discomfort caused by the roll and lateral vibration. Overestimation of discomfort due by summing the effects of them calculated separately can be avoided. After the equivalence, evaluation of discomfort and modelling of the human body can be carried out only in roll direction.

Novel MSH6 mutation predicted metastasis in eyelid and periocular squamous cell carcinoma

BACKGROUND

Our previous research revealed the relative local aggressiveness of eyelid and periocular squamous cell carcinoma (EPSCC), but its distinct genetic characteristics involved remain unknown.

OBJECTIVES

We conducted this study based on next-generation sequencing to identify the genetic distinctiveness of EPSCC and damaging mutations for possible etiology and poor prognosis.

METHODS

We performed sequencing using a 556-gene panel (smartonco) in 48 EPSCCs. Cox hazards model was applied to explore mutated genes that increase risk of metastasis and death. Pathogenesis of the mutations was predicted by sequence alignment algorithms.

RESULTS

The most commonly mutated genes were KMT2C (N=17, 35%), LRP1B (N=14, 29%), KMT2D (N=12, 25%), PTCH1(N=10, 21%) and TP53(N=10, 21%). DNA mismatch repair (MMR) genes (42%) like MSH6(19%) and MLH3(12%) were among the most frequently mutated genes. Cell cycle regulators including TP53(21%) and CDKN2A (10%) were less frequently mutated than in other squamous cell carcinomas (SCCs). Ultra violet exposure, MMR deficiency and aging were the main etiology. Of note, KMT2C has a deleterious mutation hotspot. Patients burdened with MSH6 mutation has a higher risk of overall metastasis (P=0.045, HR=5.165) and nodal metastasis (P=0.022, HR=14.038). Moreover, a hotspot mutation MSH6^E52A brought an even higher risk of nodal metastasis (P=0.011, HR=18.745).

CONCLUSIONS

EPSCCs displayed a unique mutation profile from cutaneous SCCs and mucosal SCCs. We have identified novel damaging mutations in epigenetic regulators like KMT2C boosted early onset of EPSCCs in addition to UVR, aging or MMR deficiency. And malfunction of MMR genes worsened prognosis.

Postoperative hyperprogression disease of pancreatic ductal adenocarcinoma after curative resection: a retrospective cohort study

BACKGROUND

Prognosis for patients recurred rapidly after resection of pancreatic ductal adenocarcinoma (PDAC) was extremely poor. We proposed the concept of postoperative hyper-progression disease (PO-HPD) to define recurrence within 2 months after surgery, explored the role of surgery for postoperative HPD patients and determined the predictive preoperative risk factors and genomic features of PO-HPD.

METHODS

976 patients undergoing curative resection of PDAC were enrolled. Survival data of 1733 stage IV patients from the US Surveillance, Epidemiology and End Results database was also collected. Patients relapsed were grouped into 3 groups regarding of the recurrence time (within 2 months were PO-HPD, within 2 to 12 months were early recurrence (ER) and within > 12 months were late recurrence (LR)). Risk factors for PO-HPD were explored with logistic regression models. Genomic features of 113 patients were investigated using next-generation sequencing-based gene panel testing.

RESULTS

718 of 976 cases relapsed, 101were PO-HPD, 418 were ER and 199 were LR. Total survival of PO-HPD was 12.5 months, shorter than that of ER (16.7 months) and LR (35.1 months), and verged on that of stage IV patients (10.6 months). Preoperative risk factors for PO-HPD included red blood cell count < 3.94*10^12/L, CA19-9 ≥ 288.6 U/mL, CA125 ≥ 22.3 U/mL and tumor size≥3.45 cm. Mutations of CEBPA, ATR and JAK1 were only identified in PO-HPD and they owned lower level of CN gain compared to others.

CONCLUSIONS

Prognosis of PO-HPD was extremely poor and the role of surgery for PO-HPD should be prudently assessed.

[Correlation of periodontitis and oculopathy]

With the development of researches on the relationship between periodontal health and general health, more and more evidences showed that periodontitis was closely related to oculopathy, while the mechanisms were not very clear at present. This article will focus on the influences of periodontitis on the occurrence and development of various oculopathy such as diabetic retinopathy and senile macular degeneration, and discuss the possible mechanisms of the influence by periodontitis. This will provide a theoretical basis for the new ideas on prevention and treatment of oculopathy.

POS0947 LONG-TERM GOLIMUMAB PERSISTENCE: 5-YEAR TREATMENT RETENTION DATA POOLED FROM FIVE PHASE III CLINICAL TRIALS IN PATIENTS WITH RHEUMATOID ARTHRITIS, PSORIATIC ARTHRITIS, AND ANKYLOSING SPONDYLITIS

Background

Tumor necrosis factor-alpha inhibitors (TNFi), such as golimumab (GLM), are widely prescribed for treatment of chronic immune-mediated rheumatic diseases, such as rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ankylosing spondylitis (AS). Long-term persistence of GLM response in these diseases has previously been described from individual randomized controlled trials.1-5 While treatment retention is considered an important factor for disease progression, health care utilization, and overall quality of life, and has previously been described, the probability of retention on GLM treatment in these trials has not been evaluated.

Objectives

To evaluate probability of GLM treatment retention over a 5-year period in adult patients with immune-mediated rheumatic diseases, by indication and line of therapy, using pooled data from five Phase III randomized controlled clinical trials.

Methods

Using data prospectively collected from five Phase III studies, this post-hoc analysis evaluated subcutaneous (SC) GLM (50 mg or 100 mg every 4 weeks) for up to 5 years in participants with RA (GO-BEFORE,1,6 GO-AFTER2,7 and GO-FORWARD3,8), PsA (GO-REVEAL4,9), and AS (GO-RAISE5,10). Four of the five studies (GO-BEFORE, GO-FORWARD, GO-REVEAL and GO-RAISE) were pooled to examine 1st-line GLM therapy, while the remaining study (GO-AFTER) was used to examine 2nd-line (i.e., ≥ 1 line) GLM therapy in participants who had previously received and discontinued at least one other TNFi (etanercept, adalimumab, or infliximab) for any reason. Log-rank tests were performed to estimate retention rates by indication and line of therapy. Similarly, Kaplan-Meier analysis was used to estimate the probability of GLM retention over time.

Results

Among the 2228 participants enrolled in the 5 trials, 1797 participants had received GLM as1st-line treatment (RA = 1050; PsA = 394; AS = 353) and 431 participants had received GLM as 2nd-line treatment. Compared to the pooled 1st-line GLM analysis cohort, more participants receiving 2nd-line GLM were female (78.7% vs 62.2%), were > 50 years (61.5% vs 41.2%), and had a longer disease duration (median of 9.2 years vs 3.7 years). In the pooled 1st-line studies, GLM treatment retention remained high over five years, with an overall probability of retention of 87.8% (95% confidence interval [CI], 86.2–89.2) at Year 1 (Week 52), 80.9% (79.0–82.6) at Year 2 (Week 104), 77.3% (75.3–79.2) at Year 3 (Week 156), 73.5% (71.4–75.5) at Year 4 (Week 208) and 69.8% (67.6–71.9) at Year 5 (Week 252). GLM retention rates were similar across the four 1st-line GLM studies with no notable differences observed by indication over time (Figure 1, panel A). Treatment retention was better in participants using GLM as a 1st-line therapy compared to 2nd-line therapy (Figure 1, panel B), with a probability of retention at 5 years (Week 252) with 2nd-line therapy of 41.6% (95% CI: 36.8-46.3).

Figure 1.

Conclusion

In this post-hoc analysis of prospectively collected clinical trial data, the probability of 1st-line GLM treatment retention at 5-years was consistently high across all rheumatic indications (RA, PsA and AS). Probability of long-term GLM treatment retention with 2nd-line therapy, while lower than 1st-line therapy, also remained favorable. Collectively, these data support the value of GLM as a 1st- or 2nd-line therapy in these chronic immune-mediated rheumatic diseases.

References

[1]Emery P, et al. Arthritis Rheum 2009;60:2272-83.

[2]Smolen JS, et al. Lancet 2009;374:210-21.

[3]Keystone EC, et al. J Rheumatol. 2015;43:298-306.

[4]Kavanaugh A, et al. Ann Rheum Dis. 2014;73:1689-94

[5]Inman RD, et al. Arthritis Rheum 2008;58:3402-12.

[6]Emery P, et al. Arthritis Care Res. 2016;68:744-52.

[7]Smolen JS, et al. Arthritis Res Ther. 2015;17:14.

[8]Keystone EC, et al. Ann Rheum Dis 2009;68:789-96.

[9]Kavanaugh A, et al. Arthritis Rheum 2009;60:976-86.

[10]Deodhar A, et al. Ann Rheum Dis. 2015;74:757-61.

Disclosure of Interests

Cindy Weinstein Shareholder of: Merck & Co., Inc., Kenilworth, NJ, USQA, Employee of: Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA, Marinella Govoni Shareholder of: Merck & Co., Inc., Kenilworth, NJ, USA, Employee of: MSD Italy, a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA, Jianxin Lin Shareholder of: Merck & Co., Inc., Kenilworth, NJ, USA, Employee of: Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA, Alan Meehan Shareholder of: Merck & Co., Inc., Kenilworth, NJ, USA, Employee of: Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA, Zaina Qureshi Shareholder of: Merck & Co., Inc., Kenilworth, NJ, USA, Employee of: Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA

AB0276 COMPARISON OF METABOLIC DYSFUNCTION-ASSOCIATED FATTY LIVER DISEASE WITH NON-ALCOHOLIC FATTY LIVER DISEASE IN IDENTIFYING CARDIOVASCULAR RISK IN CHINESE INDIVIDUALS WITH RHEUMATOID ARTHRITIS

Background

The nomenclature from non-alcoholic fatty liver disease (NAFLD) to metabolic dysfunction-associated fatty liver disease (MAFLD) is considered to identify more cardiovascular disease (CVD) risk in general population, and patients with rheumatoid arthritis (RA) carry an excess risk for CVD.

Objectives

To compare MAFLD with NAFLD in identifying CVD risk in RA patients.

Methods

Clinical data from a Chinese RA cohort were retrospectively analyzed. Hepatic steatosis was defined by abdominal ultrasound examination. CVD risk in RA patients was estimated by the Prediction for Atherosclerotic Cardiovascular Disease Risk in China.

Results

Among 513 included RA patients, 78.4% were female and the mean ± SD age was 51.8 ± 12.6 years. The prevalence of MAFLD and NAFLD was 21.4% and 20.5%, respectively. 10.9% RA patients concomitated with CVD events and 32.4% had a high 10-year CVD risk. Multivariate logistic regression analysis showed that both MAFLD and NAFLD were associated with an increase in CVD events (MAFLD: AOR = 2.303 [95% CI 1.197, 4.429]; NAFLD: AOR = 2.478 [95% CI 1.185, 4.779] and high 10-year CVD risk (MAFLD: AOR = 3.184 [95% CI 1.777, 5.705]; NAFLD: AOR = 2.870 [95% CI 1.597, 5.156]; all p < 0.05). The NRI and IDI was -0.011 (95% CI -0.025, 0.003) and -0.002 (95% CI -0.007, 0.002) for CVD events, and 0.012 (95% CI -0.014, 0.038) and 0.005 (95% CI -0.003, 0.013; all p > 0.05) for high 10-year CVD risk, which indicated no additional CVD events and high 10-years CVD risk were identified when replacing NAFLD with MAFLD in RA patients.

Conclusion

Both MAFLD and NAFLD are associated with an increased CVD risk which implies the importance of early detection and management of MAFLD or NAFLD in RA patients. However, new nomenclature of MAFLD identify no additional CVD risk in RA patients.

Financial support:

National Natural Science Foundation of China (No. 81971527, 82171780 and 82101892), Science and Technology Program of Guangzhou (No. 202102010188 and 201904010088), and Guangdong Basic and Applied Basic Research Foundation (No. 2019A1515011928 and 2020A1515110061).

Figure 1.

The prevalence of MAFLD and NAFLD in RA patients with different stratification.

The prevalence in different genders (A) and ages groups (B); The prevalence in different disease activity groups (C) and disease duration (D); remission (CDAI ≤ 2.8); active (CDAI > 2.8).

Disclosure of Interests

None declared

[Technical difficulties and countermeasures of digestive tract reconstruction in robotic radical gastrectomy for gastric cancer]

There still remain some problemsin digestive tract reconstruction after robotic radical gastrectomy for gastric cancer at present, such as great surgical difficulties and high technical requirements. Based on the surgical experience of the Gastric Surgery Department of Union Hospital, Fujian Medical University and the literatures at home and abroad, relevant issues are discussed in terms of robotic radical distal gastrectomy (Billroth I, Billroth II, and Roux-en-Y gastrojejunostomy), proximal gastrectomy (double-channel and double-muscle flap anastomosis), and total gastrectomy (Roux-en-Y anastomosis, functional end-to-end anastomosis, FEEA, π-anastomosis, Overlap anastomosis, and modified Overlap anastomosis with delayed amputation of jejunum, i.e. later-cut Overlap). This article mainly includes (1) The principles of digestive tract reconstruction after robotic radical gastrectomy for gastric cancer. (2) Digestive tract reconstruction after robotic radical distal gastrectomy: Aiming at the weakness of traditional triangular anastomosis, we introduce the improvement of the technical difficulty, namely "modified triangular anastomosis", and point out that because Billroth II anastomosis is a common anastomosis method in China at present, manual suture under robot is more convenient and safe, and can effectively avoid anastomotic stenosis. (3) Digestive tract reconstruction after robotic proximal gastrectomy: It mainly includes double channel anastomosis and double muscle flap anastomosis, but these reconstruction methods are relatively complicated, and robotic surgery has not been widely carried out at present. (4) Digestive tract reconstruction after robotic total gastrectomy: The most classic one is Roux-en-Y anastomosis, mainly using circular stapler for end-to-side esophagojejunal anastomosis and linear stapler for side-to-side esophagojejunal anastomosis, for which we discuss the solutions to the existing technical difficulties. With the continuous innovation of robotic surgical system and anastomosis instruments, and with the gradual improvement of anastomosis technology, it is believed that digestive tract reconstruction after robotic radical gastrectomy for gastric cancer will have a good application prospect in gastric cancer surgery.

OP0163 A MATRIX PREDICTION MODEL FOR THE SIX-MONTH MORTALITY RISK IN PATIENTS WITH ANTI-MELANOMA DIFFERENTIATION-ASSOCIATED PROTEIN-5 POSITIVE DERMATOMYOSITIS

Background

Recently, the autoantibody recognizing melanoma differentiation-associated gene 5 (anti-MDA5) is of the greatest concern as a specific autoantibody of dermatomyositis (DM), since it delineates a unique clinical phenotype of DM with a high risk of life-threatening lung complications. Considering routine clinical characteristics at baseline are still desired candidates for screening potential mortality predictors, in order to as early as possible stratify the mortality risk in anti-MDA5 positive DM patients before making therapeutic strategies.

Objectives

To investigate the baseline independent risk factors for predicting 6-month mortality of anti-MDA5-positive DM patients and develop a matrix prediction model formed by these risk factors.

Methods

This was a real-world prospective observational study. The hospitalized patients with DM were included if they fulfilled the criteria including: aged over 18 years old; diagnosed as having DM according to the criteria proposed by Bohan and Peter or the modified Sontheimer definitions; and positive anti-MDA5 which was determined by both line immunoassay testing and enzyme-linked immunosorbent testing. The primary outcome was all-cause 6-month mortality after enrolment. A matrix prediction model was built with the mortality risk probability.

Results

There were 82 DM patients enrolled (mean age of onset 50±11 years and 63% female), with 40 (49%) showing positive anti-MDA5. Gottron sign/papules (OR: 5.135, 95%CI: 1.489~17.708), arthritis (OR: 5.184, 95%CI: 1.455~18.467), interstitial lung disease (ILD, OR: 7.034, 95%CI: 1.157~42.785), and higher level of C4 (OR: 1.010, 95%CI: 1.002~1.017) were independent associators with positive anti-MDA5 in DM patients. Anti-MDA5-positive DM patients had significant higher 6-month all-cause mortality than those with anti-MDA5-negative (30% vs. 0%). Among anti-MDA5-positive DM patients, compared to the survivors, non-survivors had significantly advanced age of onset (59±6 years vs. 46±9 years), higher rates of fever (75% vs. 18%), positive carcinoma embryonic antigen (CEA, 75% vs. 14%), higher level of ferritin (median 2858 ug/L vs. 619 ug/L, all p<0.05). Multivariate COX regression showed ferritin≥1250 μg/L (HR: 10.4, 95%CI: 1.8~59.9), fever (HR: 11.2, 95%CI: 2.5~49.9), and positive CEA (HR: 5.2, 95%CI: 1.0~25.7) were independent risk factors of 6-month mortality.

According to the matrix prediction model, anti-MDA5-positive DM patients could be stratified into three subgroups based on various probabilities of predicted mortality: (i) High-risk: eight patients with two of the above three features (including fever, serum ferritin≥1250 μg/L, and positive CEA) had high predicted mortality probability with 64%~85% (three red grids in Figure 1A), and the actual mortality was 75% (n=6) with 60%, 100%, and 100% respectively in three red grids (Figure 1B). Five patients with all of three features had extremely high predicted mortality probability with 97% (95%CI: 70%~100%, the dark red grid of Figure 1A), and the actual mortality was 100% in Figure 1B; (ii) Moderate-risk: nine patients with one of the above three features had moderate predicted mortality probability with 11%~29% (three yellow grids in Figure 1A), and the actual mortality was 11% (n=1) with 0%, 0%, and 17% respectively in three yellow grids (Figure 1B); (iii) Low-risk: eighteen patients with none of the above three features had low predicted mortality probability with 2% (95%CI: 0.2%~20%, the green grid in Figure 1A), and the actual mortality was 0% in the green grid (Figure 1B).

Conclusion

Baseline characteristics of fever, positive CEA, and ferritin≥1250 μg/L are risk factors for 6-month all-cause mortality in anti-MDA5-positive DM patients. A novel matrix prediction model composed of these three clinical indicators is firstly proposed to provide a chance for exploration of individual treatment strategies in anti-MDA5-positive DM subgroups with various probabilities of mortality risk.

Disclosure of Interests

None declared

[Identification of rare variants in exons of NLRC4 gene in patients with type 1 diabetes and their impact on gene function]

Objective: To identify rare variants in exon and exon-intron boundary of containing NLR family CARD domain protein 4 (NLRC4) in type 1 diabetes (T1DM) patients, and to explore their effects on gene function. Methods: A total of 508 T1DM patients and 527 healthy controls in the Department of Metabolic Endocrinology, Second Xiangya Hospital of Central South University from August 2017 to September 2020 were selected. The case group included 264 males and 244 females, and the age [M (Q₁, Q₃)] was [27 (11, 43)] years. The control group included 290 males and 237 females, and their age［M（Q₁，Q₃）］was [47 (36, 60)] years old. Identification of rare variants in exons of NLRC4 gene in T1DM patients and healthy controls was performed and verified by next-generation sequencing and sanger sequencing. The NLRC4 gene wild-type and mutant plasmids were constructed and transfected into 293T cells. Western blot (WB) was used to detect the expression of NLRC4 protein and cleavage products of pro-cysteinyl aspartate specific proteinase(procaspase-1). Cycloheximide (CHX) was added to 293T cells transfected with wild-type or mutant NLRC4 plasmid to detect the degradation of NLRC4 protein. The localization of NLRC4 protein was detected by immunofluorescence, and the concentration of IL-1β in the cell supernatant was detected by enzyme-linked immunosorbent assay (ELISA). Results: The sequencing results showed that 4 patients and 2 healthy controls had a heterozygous variant c.208C>T in exon 3 of the NLRC4 gene. Two patient had a heterozygous variant c.1564T>C in exon 4, and 1 patients had c.1219G>C in exon 4. These three variants might be pathogenic variants in T1DM. In 293T cells transfected with NLRC4 wild-type and c.208C>T、c.1564T>Cc.1219G>C mutant plasmids, the expression level, degradation rate, localization of NLRC4 protein and the content of cleavage products of procaspase-1 did not change significantly. However, the concentration of IL-1β secreted by 293T cells transfected with c.1219G>C and c.208C>T plasmid [M(Q₁, Q₃)] was 15.25 (12.98, 17.52) and 15.44 (13.81, 17.07) ng/L, respectively, which was lower than 18.70 (16.59, 20.81) ng/L of 293T cells transfected wild-type plasmid (P=0.020, 0.010). Conclusions: NLRC4 gene rare variants c.208C>T, c.1564T>C and c.1219G>C may not change the protein expression, degradation and localization, but c.208C>T and c.1219G>C may inhibit the secretion of IL-1β. This result suggests that NLRC4 rare variants may have an impact on gene function.

[Establishment of artificial neural network model for predicting lymph node metastasis in patients with stage Ⅱ-Ⅲ gastric cancer]

Objective: To establish a neural network model for predicting lymph node metastasis in patients with stage II-III gastric cancer. Methods: Case inclusion criteria: (1) gastric adenocarcinoma diagnosed by pathology as stage II-III (the 8th edition of AJCC staging); (2) no distant metastasis of liver, lung and abdominal cavity in preoperative chest film, abdominal ultrasound and upper abdominal CT; (3) undergoing R0 resection. Case exclusion criteria: (1) receiving preoperative neoadjuvant chemotherapy or radiotherapy; (2) incomplete clinical data; (3) gastric stump cancer.Clinicopathological data of 1231 patients with stage II-III gastric cancer who underwent radical surgery at the Fujian Medical University Union Hospital from January 2010 to August 2014 were retrospectively analyzed. A total of 1035 patients with lymph node metastasis were confirmed after operation, and 196 patients had no lymph node metastasis. According to the postoperative pathologic staging. 416 patients (33.8%) were stage Ⅱ and 815 patients (66.2%) were stage III. Patients were randomly divided into training group (861/1231, 69.9%) and validation group (370/1231, 30.1%) to establish an artificial neural network model (N+-ANN) for the prediction of lymph node metastasis. Firstly, the Logistic univariate analysis method was used to retrospectively analyze the case samples of the training group, screen the variables affecting lymph node metastasis, determine the variable items of the input point of the artificial neural network, and then the multi-layer perceptron (MLP) to train N+-ANN. The input layer of N+-ANN was composed of the variables screened by Logistic univariate analysis. Artificial intelligence analyzed the status of lymph node metastasis according to the input data and compared it with the real value. The accuracy of the model was evaluated by drawing the receiver operating characteristic (ROC) curve and obtaining the area under the curve (AUC). The ability of N+-ANN was evaluated by sensitivity, specificity, positive predictive values, negative predictive values, and AUC values. Results: There were no significant differences in baseline data between the training group and validation group (all P>0.05). Univariate analysis of the training group showed that preoperative platelet to lymphocyte ratio (PLR), preoperative systemic immune inflammation index (SII), tumor size, clinical N (cN) stage were closely related to postoperative lymph node metastasis. The N+-ANN was constructed based on the above variables as the input layer variables. In the training group, the accuracy of N+-ANN for predicting postoperative lymph node metastasis was 88.4% (761/861), the sensitivity was 98.9% (717/725), the specificity was 32.4% (44/136), the positive predictive value was 88.6% (717/809), the negative predictive value was 84.6% (44/52), and the AUC value was 0.748 (95%CI: 0.717-0.776). In the validation group, N+-ANN had a prediction accuracy of 88.4% (327/370) with a sensitivity of 99.7% (309/310), specificity of 30.0% (18/60), positive predictive value of 88.0% (309/351), negative predictive value of 94.7% (18/19), and an AUC of 0.717 (95%CI:0.668-0.763). According to the individualized lymph node metastasis probability output by N+-ANN, the cut-off values of 0-50%, >50%-75%, >75%-90% and >90%-100% were applied and patients were divided into N0 group, N1 group, N2 group and N3 group. The overall prediction accuracy of N+-ANN for pN staging in the training group and the validation group was 53.7% and 54.1% respectively, while the overall prediction accuracy of cN staging for pN staging in the training group and the validation group was 30.1% and 33.2% respectively, indicating that N+-ANN had a better prediction than cN stage. Conclusions: The N+-ANN constructed in this study can accurately predict postoperative lymph node metastasis in patients with stage Ⅱ-Ⅲ gastric cancer. The N+-ANN based on individualized lymph node metastasis probability has better accurate prediction for pN staging as compared to cN staging.

Solitary fibrous tumour of the sacrum: A report of 2 cases with review of the literature

INTRODUCTION

Solitary fibrous tumour (SFT) of the sacrum is a very rare disease. So far, there have been few reports on this disease. Here, we reported 2 such cases and reviewed the other 7 reports in the literature.

CASE SERIES

Case 1, a 48-year-old man presented with lumbosacral pain for 2 months and numbness in the left plantar region for more than 1 month. The report of CT scan indicated that the sacrum was destroyed and the soft tissue mass projected into the pelvis. Histopathology showed that the cells were fusiform or short fusiform, arranged in strips, sheets, and wavy patterns. Case 2, a 40-year-old woman presented with hip joint pain and lower extremity dyskinesia for more than 2 months. The result of the MRI examination demonstrated a mass on the right sacral foramen and anterior sacrum. The characteristics of histopathology are ovoid or spindle-shaped cells with focal nuclear pleomorphism and prominently branched, hemangiopericytoma-like vascular patterns. In addition, immunohistochemical showed that CD34, Bcl-2, CD99, STAT6 and vimentin were positive, while Desmin, MSA, EMA, S100 were negative in both cases.

CONCLUSION

Previous literatures have revealed that SFTs of the sacrum are rare neoplasms. Case 1 and a part of these lesions previously reported seem to be malignant and should be treated with surgery. Radiation or chemotherapy was adopted if necessary. Since SFT of the sacrum is prone to recur and metastasis, long-term follow-up should be considered. To a certain extent, new risk stratification models can predict prognosis more accurately.