Molecular characterization and expression profiles of six genes involved in vitellogenic deposition and hydrolysis of Chinese sturgeon (Acipenser sinensis) suggesting their transcriptional regulation on ovarian development

Ovary development of Chinese sturgeon (Acipenser sinensis) in controlled breeding has been reported to respond to dietary lipid levels. However, the corresponding molecular regulatory mechanism about ovary development of Chinese sturgeon is still unclear. To elucidate the molecular mechanism of vitellogenic deposition and hydrolysis, six key genes, namely, vtgr (vitellogenin receptor), atp6v1c1 (Vacuolar H⁺-ATPase subunit c1), atp6v1h (Vacuolar H⁺-ATPase subunit h), ctsb (cathepsin B), ctsd (cathepsin D) and ctsl (cathepsin L) involved in vitellogenic deposition and hydrolysis of Chinese sturgeon were cloned and characterized, and their spatio-temporal mRNA expression profiles as well as transcriptional responses to dietary lipid level were investigated. The full-length cDNA sequences of these six genes showed similar domain structure to their respective orthologous genes from other vertebrates. Tissue-specific expression patterns of these genes were observed in ovary, liver, muscle, spleen, brain, gill, intestine, heart, stomach and kidney. Ovarian expression level of vtgr was the highest in stage II, and ctsl expression was the highest in stage IV, while the mRNA expressions of other 4 genes were the highest in stage III. The increase of dietary lipid level promoted ovary development and elevated the expressions of vtgr, atp6v1c1, atp6v1h, ctsb and ctsd in the ovary. The results of the present study indicated that these genes are crucial for vitellogenic deposition, and provided a preliminary understanding on the molecular regulation of vitellogenic deposition and hydrolysis during ovary development of Chinese sturgeon.

MiRNA-7b-5p attenuates the progression of osteoporosis by inhibiting adipose differentiation of hMSCs via regulating IRS2

OBJECTIVE

To elucidate whether microRNA-7b-5p (miRNA-7b-5p) could inhibit adipose differentiation of human bone marrow-derived mesenchymal stem cells (hMSCs) through regulating IRS2, thereby alleviating the progression of osteoporosis.

MATERIALS AND METHODS

Expression levels of miRNA-7b-5p and IRS2 in hMSCs at different stages of adipogenic differentiation and osteogenic differentiation were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot. After transfection of miRNA-7b-5p mimic or pcDNA-IRS2 in hMSCs, lipid droplet formation in cells was observed by oil red O staining. Expressions of C/EBPα and PPARγ were detected by qRT-PCR and Western blot. The potential target gene of miRNA-7b-5p was predicted by bioinformatics and verified by dual-luciferase reporter gene assay. Finally, expressions of IRS2 in hMSCs transfected with miRNA-7b-5p-NC, miRNA-7b-5p mimic or co-transfected with miRNA-7b-5p mimic and pcDNA-IRS2 were examined.

RESULTS

Expressions of miRNA-7b-5p and IRS2 gradually decreased with the prolongation of adipogenic differentiation, but increased during osteogenic differentiation of hMSCs. Transfection of miRNA-7b-5p mimic reduced oil red O staining after adipogenic differentiation and downregulated mRNA and protein levels of C/EBPα and PPARγ. Transfection of pcDNA-IRS2 increased oil red O staining after osteogenic differentiation and upregulated mRNA and protein levels of C/EBPα and PPARγ. Dual-luciferase reporter gene results showed that miRNA-7b-5p could bind to IRS2. Overexpression of IRS2 reversed the downregulated mRNA and protein levels of adipogenic-related genes C/EBPα and PPARγ due to the overexpression of miRNA-7b-5p.

CONCLUSIONS

MiRNA-7b-5p inhibits the adipogenic differentiation of hMSCs through IRS2, thus alleviating the development of osteoporosis.

Cryopreservation of germline stem cells in American paddlefish (Polyodon spathula)

Most sturgeon and paddlefish are critically endangered; therefore, effective measures to conserve these genetic resources are required. Cryopreservation of gonad tissues containing germline stem cells could be an effective strategy for long term preservation and restoration of fish species using germ cell transplantation procedure. The aim of this study was to develop an optimal procedure for long-term cryopreservation of American paddlefish gonads using a slow-freezing method. Through optimization of permeating cryoprotectants, nonpermeating cryoprotectants, and supplementation of proteins, gonad tissues were frozen with a cryomedium containing 1.3 M dimethyl sulfoxide, 0.1 M trehalose, and 10 % fetal bovine serum at a cooling rate of -1 °C/min. This method was also successfully utilized for the cryopreservation of Yangtze sturgeon testes. Viability of gonadal cells isolated from frozen gonads was not different from cells isolated from fresh gonadal tissues, while the number of gonadal cells dissociated from frozen gonads was less. Germline stem cells dissociated from long-term (1 year) cryopreserved gonads were labeled with PKH26 fluorescent dye and intraperitoneally transplanted into larvae of Yangtze sturgeon. The colonization of transplanted germline stem cells was confirmed by the presence of PKH26-labeled donor germline stem cells and donor-derived mtDNA sequence in the recipient gonads, providing evidence that germline stem cells from sturgeon and paddlefish gonads that had been preserved for a long period maintained their functions. The results of present study indicate the procedures used are effective for long-term preservation of critically endangered species within the Acipenseriformes order which can later be regenerated using surrogate broodstock technology.

Spastic paraplegia as the only symptom in two adult-onset patients carrying a novel pathogenic variant in PYCR2

A novel pathogenic PYCR2 variant and corresponding brain images in two patients characterized by spastic paraplegia.

MicroRNA-330-5p promotes the development of osteosarcoma by regulating SPRY2

OBJECTIVE

MicroRNA is an endogenous, non-coding small RNA that has a significant role in regulating organisms and pathology. Previous studies have demonstrated that microRNA-330-5p was a cancer-promoting gene. However, the role of microRNA-330-5p in osteosarcoma (OS) has not been reported. The aim of this work was to explore the characteristics of microRNA-330-5p expression in OS, and to further study its expression in OS and its relationship with clinicopathological parameters and prognosis.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to investigate the expression of microRNA-330-5p in 48 pairs of OS tissues and paracancer tissues, and to analyze the relationship between the expression of microRNA-330-5p and OS clinical indicators and patient prognosis. Meanwhile, qRT-PCR was performed to verify the microRNA-330-5p expression in OS cells. In addition, the microRNA-330-5p knockdown expression model was constructed using lentivirus in OS cell lines U2OS and MG63. The effects of microRNA-330-5p on the biological function of OS cells were analyzed by Cell Counting Kit-8 (CCK-8) and transwell experiments. The potential mechanism was explored by Western blot.

RESULTS

In this paper, qRT-PCR results showed that the expression of microRNA-330-5p in OS was higher than that in paracancer tissues, and the difference was statistically significant. Compared with microRNA-330-5p low expression group, patients with high expression of microRNA -330-5p had a higher prevalence of distant metastasis and a lower overall survival rate. In vitro experiment showed that the proliferation, invasion and metastasis abilities of the cells in the microRNA-330-5p silencing group were markedly decreased compared with the negative control group (NC group). Western blot results demonstrated that microRNA-330-5p inhibitor can activate SPRY2 and regulate the expression of key proteins, such as p-Smad2, p-Smad3, TGF-β1, MMP9 and Vimentin in the TGF-β1/Smad signaling pathway. It was found that there was a mutual regulation between microRNA-330-5p and SPRY2, which promoted the malignant progression of OS.

CONCLUSIONS

The expression of microRNA-330-5p was markedly increased in OS, which was associated with distant metastasis and poor prognosis. Furthermore, we found that microRNA-330-5p may promote the vicious progression of OS by inter-modulating SPRY2 and the TGF-β1/Smad signaling pathways.

Assessment of Yangtze sturgeon as recipient for the production of American paddlefish gametes through spermatogonia transplantation

The Chinese paddlefish (Psephurus gladius), one of the world's largest freshwater fish, was last seen alive in 2003; they are presumed now to be extinct. In fish, germ cell transplantation is currently known as one of the most powerful assisted reproductive technologies for the conservation of endangered species. In the event that a Chinese paddlefish is unexpectedly caught in the near future, we aimed to develop an experimental strategy to produce paddlefish gametes in the gonads of surrogate sturgeon. Spermatogonia were collected from the testes of 2.5-year-old immature male American paddlefish (Polyodon spathula), the species most closely related to the Chinese paddlefish, by Percoll gradient centrifugation, and transplanted into the peritoneal cavity of Yangtze sturgeon (Acipenser dabryanus) larvae at 7-8 days post-hatch. At two months post-transplantation, donor-derived spermatogonia had efficiently colonized in the recipient gonads and proliferated. A PCR analysis developed to detect xenogenic donor-derived mtDNA sequences in recipient gonads revealed that American paddlefish germ cells survived for at least seven months after transplantation in the gonads of Yangtze sturgeon recipients. These results show that the somatic microenvironment of Yangtze sturgeon gonads was able to support the colonization, proliferation, and survival of xenogeneic germ cells from a different taxonomic family. This study provides key information that could lead to future restoration of Chinese paddlefish using germ cell transplantation.

Metabolomics and gene expressions revealed the metabolic changes of lipid and amino acids and the related energetic mechanism in response to ovary development of Chinese sturgeon (Acipenser sinensis)

Captive breeding has been explored in Chinese sturgeon (Acipenser sinensis) for species protection. However, gonad development from stage II to IV of cultured female broodstocks is a handicap. This study aimed to explore the physiological and metabolic changes during the ovary development from stage II to IV of female Chinese sturgeon and the related energy regulatory mechanism, which may be helpful to address the developmental obstacle. The results showed that the oocyte volume increased and the muscle lipid content decreased with the ovary development. Ovarian RNA levels of most genes related to lipid and amino acid metabolism were higher in stage II and III than in stage IV. Serum contents of differential metabolites in arginine, cysteine, methionine, purine, tyrosine, lysine, valine, leucine and isoleucine metabolism pathways peaked at stage III, while the contents of sarcosine, alanine and histidine, as well as most oxylipins derived from fatty acids peaked at stage IV. These results indicated the more active amino acids, lipid metabolism, and energy dynamics of fish body in response to the high energy input of ovary developing from stage II to III, and the importance of alanine, histidine, taurine, folate and oxylipins for fish with ovary at stage IV.

AB1104 ANALYSIS OF ANTINUCLEAR ANTIBODY TITERS AND PATTERNS USING HEP 2 INDIRECT IMMUNOFLUORESCENCE IN VARIOUS LIVER DISEASES

Background:

Abnormal liver function can be seen in not only hepatitis B virus infection (HBV), hepatitis C virus infection (HCV), hepatic carcinoma (HCC), but also in primary biliary cirrhosis (PBC), autoimmune hepatitis (AIH), and systemic autoimmune rheumatic diseases (SARD). Antinuclear antibody (ANA) testing using indirect immunofluorescence assay (IIFA) is a common and economical method which contributes to detect SARD and autoimmune liver diseases [1].

Objectives:

Our objective was to investigate ANA positivity, titers and their patterns in multiple liver diseases, including PBC, AIH, HBV, HCV, and HCC, compared to healthy controls (HC).

Methods:

2537 patients with SARD, 137 PBC cases, 57 AIH cases, 3420 HBV cases, 769 HCV cases, 268 HCC cases, and 1073 HC were retrospectively assessed. The titers and patterns of ANA were detected with the IIFA method.

Results:

ANA positivity rate was considerably discernible between these diseases, which is 90.1% in SARD, 93.4% in PBC, 49.1% in AIH, 19.1% in HBV, 13.9% in HCV and 23.5% in HCC. Moreover, only 4.9% of HCC cases, 2.5% of HBV patients and 1.6% of HCV patients had an ANA titer ≥ 1:320. The mixed pattern which composed of at least two patterns majorly lied in PBC. AC-15 and AC-21 was frequently related to liver diseases; the former pattern was more frequently found in AIH (84.2%) and PBC (8.8%), and the latter pattern was easily seen in PBC (62.2%) and HCC (22.6%). The positive rate of ANA in HC was 12.2% and its major pattern was AC-2.

Conclusion:

There are differences in ANA positivity among patients with SARD and various liver diseases. Some mixed patterns may provide important evidence for the diagnosis of PBC. Clinicians should pay attention to ANA patterns and titer during the interpretation of this test.

References:

[1]Damoiseaux J, Andrade L, Carballo OG, Conrad K, Francescantonio P, Fritzler MJ, Garcia DLTI, Herold M, Klotz W, Cruvinel WM, Mimori T, von Muhlen C, Satoh M, Chan EK, (2019) Clinical relevance of HEp-2 indirect immunofluorescent patterns: the International Consensus on ANA patterns (ICAP) perspective. ANN RHEUM DIS 78: 879-889

Figure 1.

The Proportion of Each ANA Pattern Exhibited in Different Diseases and HCANA: antinuclear antibodies; HC: healthy controls; PBC: primary biliary cirrhosis; AIH: autoimmune hepatitis; SARD: systemic autoimmune rheumatic diseases; HBV: hepatitis B virus infection: HCV: hepatitis C virus infection: HCC: hepatic carcinoma.

Acknowledgments:

None.

Disclosure of Interests:

None declared

AB0132 ALTERATIONS IN PERIPHERAL T-CELLS AND B-CELLS SUBSETS IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND SJÖGREN’S SYNDROME UNDERGOING THERAPEUTIC PLASMA EXCHANGE OR IMMUNOADSORPTION

Background:

Systemic lupus erythematosus (SLE) and Sjögren’s syndrome (SS) are systemic autoimmune diseases characterized by a broad spectrum of clinical manifestations and disease course. Alternative therapies such as therapeutic plasma exchange (TPE), immunoadsorption are recommended to the patients who lack a good response to standard therapy [1].

Objectives:

Our observational study was to explored whether abnormalities in T-cells, B-cells and their subtypes were present in the patients who had TPE or immunoadsorption in patients with SLE and SS compared with healthy controls (HC).

Methods:

Demographic, clinical variables and autoantibodies were recorded. Flow cytometry was used to establish the frequencies of lineage subsets. Monoclonal antibodies against 21 surface markers such as CD3, CD4, CD8, were used to distinguish and evaluate T-cells’ and B-cells’ subpopulation. SLE acvity was measured using systemic lupus erythematosus disease activity index (SLEDAI). Comparisons between subgroups were undertaken using paired T-test, Mann-Whitney U test and ANOVA.

Figure 1.

Altered expression of CD4+ T-cell subsets in the patients with SLE and SS after treated with plasma exchange or immunoadsorption

Results:

6 SS patients and 1 SLE patient underwent immune adsorption, while the other 5 SLE patients had plasma exchange all for three times. There was no significant difference among SLE, SS and HC in the proportion of T-cells and B-cells. The proportion of CD3-CD19+CD27+IgD+ B-cells were reduced in SLE, while CD3+CD4+CD25+CD127- T-cells were elevated in SS. The proportion of CD3+CD4+CD45RA+CCR7+T-cells were increased (p= 0.045), while CD3+CD4+CD25+CD127- T-cells were declined (p= 0.027) and CD3+CD4+CXCR5+PD-1+ T-cells went down after the therapies (p≤ 0.030). The proportion of CD3-CD19+IgD-IgM-CD27+CD38+ B-cells was also reduced after TPE or immunoadsorption (p= 0.032) with ANA titers and IgG decreasing dramatically. SLEDAI scores were reduced after the therapy in SLE patients.

Conclusion:

The T-cell and B-cell’s profiles were proved to have alteration after TPE or immunoadsorption which shed light on the complicated mechanisms of these relatively novel therapy in SLE and SS.

References:

[1]Bertsias GK, Tektonidou M, Amoura Z, et al. Joint European League Against Rheumatism and European Renal Association-European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of adult and paediatric lupus nephritis. ANN RHEUM DIS 2012;71:1771-1782.

Acknowledgments:

None.

Disclosure of Interests:

None declared

AB0727 WORK OUTCOMES AND ASSOCIATED FACTORS IN ANKYLOSING SPONDYLITIS PATIENTS IN CHINA

Background:

Poorer work productivity due to pain and functional impairment is commonly seen in ankylosing spondylitis (AS) patients, which may contribute to huge social economic burden. However, data about work outcomes and associated factors in Chinese AS patients were barely reported.

Objectives:

To assess work outcomes and identify factors associated with poor work productivity in patients with AS in China.

Methods:

A cross-sectional study was conducted in China. Adult patients (aged ≥ 18 years) fulfilled the 1984 New York modified criteria of AS were enrolled from rheumatology center from Jan 2017 to Aug 2017. All participants completed questionnaires about socio-demographic characteristics, disease characteristics, quality of life and the Work productivity and activity impairment questionnaire in AS (WPAI:SpA) to accesses the impact of chronic health conditions on job performance and productivity. Factors associated with work outcomes were evaluated.

Results:

A total of 91 patients with AS were included: 87.8% males, 78.02% employed, mean age and disease duration of 30 and 10 years respectively. The mean (SD) activity impairment of all patients was 48.57% (22.02%). For patients with employed work, mean (SD) absenteeism, presenteeism and work productivity loss were 10.22% (19.44%), 43.86% (22.48%) and 47.92% (25.81%) respectively. In multivariable analysis, activity impairment was associated with Bath Ankylosing Spondylitis Functional Index (BASFI) (P<0.01) and Ankylosing Spondylitis Quality of Life (ASQoL) (P<0.01). Absenteeism was associated with disease duration (P=0.03). Presenteeism was associated with disease duration (P=0.04), BASFI (P<0.01) and ASQoL (P<0.01). Work productivity loss was associated with BASFI (P<0.01) and ASQoL (P<0.01).

Conclusion:

Longer disease duration, reduced physical function and poorer quality of life are associated with reduced work productivity in Chinese AS patients.

References:

[1]Boonen A, van der Heijde D, Landewe R, Spoorenberg A, Schouten H, Rutten-van Molken M, et al. Work status and productivity costs due to ankylosing spondylitis: comparison of three European countries. Annals of the rheumatic diseases. 2002;61(5):429-37.

[2]Martindale J, Shukla R, Goodacre J. The impact of ankylosing spondylitis/axial spondyloarthritis on work productivity. Best Pract Res Clin Rheumatol. 2015;29(3):512-23.

[3]Castillo-Ortiz JD, Ramiro S, Landewe R, van der Heijde D, Dougados M, van den Bosch F, et al. Work Outcome in Patients With Ankylosing Spondylitis: Results From a 12-Year Followup of an International Study. Arthritis Care Res (Hoboken). 2016;68(4):544-52.

[4]Sag S, Nas K, Sag MS, Tekeoglu I, Kamanli A. Relationship of work disability between the disease activity, depression and quality of life in patients with ankylosing spondylitis. J Back Musculoskelet Rehabil. 2018;31(3):499-505.

[5]Goh Y, Kwan YH, Leung YY, Fong W, Cheung PP. A cross-sectional study on factors associated with poor work outcomes in patients with axial spondyloarthritis in Singapore. Int J Rheum Dis. 2019;22(11):2001-8.

Disclosure of Interests:

None declared

AB0049 IMMUNE DYSFUNCTION IN ANKYLOSING SPONDYLITIS (AS) AND THE POTENTIAL OF TUMOR NECROSIS FACTOR-Α (TNF-α) INHIBITOR ANBAINUO AS AN EFFECTIVE TREATMENT

Background:

Studies into ankylosing spondylitis (AS) and its relationship with immune function are controversial, and the correlation between the efficacy of TNF-α inhibitor and changes in immune function is unclear.

Objectives:

We conducted a prospective study of T-cell and B-cell subset distribution and analyzed lymphocyte function in AS patients to further clarify changes to the immune system caused by AS and to explore resistance that could contribute to relapse after treatment.

Methods:

A total of 40 immune cells were tested with flow cytometry, and the results of 105 HC (healthy control) subjects, 177 active-stage AS patients, and 23 AS cases before and after 12 weeks of Anbainuo therapy were analyzed.

Results:

Compared with the HC group, the proportion of immune cells, such as naïve and central memory CD4+T cells, in AS increased (p<0.0001), but effector memory and terminally differentiated CD4+T cells were decreased (p<0.01 and 0.0001, respectively). Naïve, central memory, and effector memory CD8+T cells were increased (p<0.0001, 0.001, and 0.01, respectively), but terminally differentiated CD8+T cells were decreased (p<0.0001). Th1 cells (helper T cells-1), Tfh1 cells (follicular helper T cells-1), Tc1 cells (cytotoxic T cells-1), and Tregs (regulatory T cells) were lower (p<0.01, 0.05, 0.0001, and 0.001, respectively), but Th17 cells, Tfh17 cells, and Tc cells were higher (p<0.001, 0.0001 and 0.001, respectively). The proportions of total B cells and class-switched B cells were increased (p<0.05), but non-switched B cells, plasma cells, memory B cells, and immature Bregs (regulatory B cells) were lower (p<0.01, 0.0001, 0.0001, and 0.0001, respectively). After Anbainuo therapy, the percentage of Tregs and B10 cells (IL-10-producing regulatory B cells) had increased (p<0.01and 0.05, respectively), and the increase in Tregs was positively correlated with the decrease in CRP (C-reactive protein) (r= 0.489, p=0.018).

Conclusion:

We found that, in terms of both innate and acquired immunity, active-stage AS patients have an immunity imbalance involving multiple types of immune cells, including CD4+T cells, CD8+T cells, Th cells, Tfh cells, Tc cells, Tregs, Bregs, and B cells. Anbainuo can not only help to inhibit disease activity and partial immune function imbalance in AS but can also increase the number of negative regulatory cells in inflammation.

References:

[1]Long, S., et al., High frequency of circulating follicular helper T cells is correlated with B cell subtypes in patients with ankylosing spondylitis. Exp Ther Med, 2018. 15(5): p. 4578-4586.

[2]An, H., et al., The absolute counts of peripheral T lymphocyte subsets in patient with ankylosing spondylitis and the effect of low-dose interleukin-2. Medicine (Baltimore), 2019. 98(15): p. e15094.

Acknowledgments:

Thanks to Professor Zhinan Yin for his support and assistance with this study

Disclosure of Interests:

None declared

Adjusting the Prerelease Gut Microbial Community by Diet Training to Improve the Postrelease Fitness of Captive-Bred Acipenser dabryanus

As one of the most important tool for biodiversity restoration and endangered species conservation, reintroduction has been implemented worldwide. In reintroduction projects, prerelease conditioning could effectively increase postrelease fitness and survival by improving animals’ adaptation to transformation from artificial to natural environments. However, how early-life diet training affects individuals’ adaptation, fitness, and survival after release remains largely unknown. We hypothesized that early-life diet training would adjust the host’s gut microbial community, the gut microbial community would influence the host’s diet preference, and the host’s diet preference would impact its adaptation to diet provision transformation and then determine postrelease fitness and survival. To verify this hypothesis, we investigated the growth characteristics and gut microbes of Yangtze sturgeon (Acipenser dabryanus) trained with natural and formula diets at both the prerelease and postrelease stages. The results showed that (1) the gut microbial communities of the individuals trained with a natural diet (i.e., natural diet group) and formula diet (i.e., formula diet group) evolved to the optimal status for their corresponding diet provisions, (2) the individuals in the natural diet group paid a lower cost (i.e., changed their gut microbial communities less) during diet transformation and release into the natural environment than did the individuals in the formula diet group, and (3) the gut microbes in the natural diet group better supported postrelease fitness and survival than did the gut microbes in the formula diet group. The results indicated that better prerelease diet training with more appropriate training diets and times could improve the reintroduction of Yangtze sturgeon by adjusting the prerelease gut microbial community. Because a relationship between diet (preference) and gut microbes is common in animals from insects (such as Drosophila melanogaster) to mammals (such as Homo sapiens), our hypothesis verified by the case study on Yangtze sturgeon applies to other animals. We therefore encourage future studies to identify optimal training diets and times for each species to best adjust its prerelease gut microbial community and then improve its postrelease fitness and survival in reintroduction projects.

Extinction of one of the world's largest freshwater fishes: Lessons for conserving the endangered Yangtze fauna

The mega river ecosystem of the Yangtze River was once home to diverse aquatic megafauna but is increasingly affected by various anthropogenic stressors that have resulted in continuous loss of biodiversity, such as the probable extinction of Yangtze River Dolphin. The Chinese paddlefish, Psephurus gladius, was one of only two extant members of a relict lineage that was most diverse and widespread 34-75 million years ago. It is also one of the largest freshwater fish species, reaching up to 7 m in length. The Chinese paddlefish was once common in the Yangtze River, with c.25 t being harvested per annum during the 1970s. Populations have, however, declined drastically since the late 1970s as a result of overfishing and habitat fragmentation. Here, a basin-wide capture survey during 2017-2018 found 332 fish species, but did not find a single specimen of Chinese paddlefish. Furthermore, 140 historically reported fish species have not been found and most of them are considered highly endangered. Based on 210 sightings of Chinese paddlefish during the period 1981-2003, we estimated the timing of extinction to be by 2005, and no later than by 2010. In addition, the paddlefish probably became functionally extinct (i.e. it was unable to reproduce) by 1993, before it went extinct. It is likely that the lack of reproduction was among the major causes of extinction. As no individuals exist in captivity, and no living tissues are conserved for potential resurrection, the fish should be considered extinct according to the IUCN Red List criteria. The delayed extinction of Chinese paddlefish resulted from multiple threats, suggesting that optimizing conservation efforts on endangered Yangtze fauna is urgently needed.

Genetic variants in the folate metabolic pathway genes predict cutaneous melanoma-specific survival

BACKGROUND

Folate metabolism plays an important role in DNA methylation and nucleic acid synthesis and thus may function as a regulatory factor in cancer development. Genome-wide association studies (GWASs) have identified some single-nucleotide polymorphisms (SNPs) associated with cutaneous melanoma-specific survival (CMSS), but no SNPs were found in genes involved in the folate metabolic pathway.

OBJECTIVES

To examine associations between SNPs in folate metabolic pathway genes and CMSS.

METHODS

We comprehensively evaluated 2645 (422 genotyped and 2223 imputed) common SNPs in folate metabolic pathway genes from a published GWAS of 858 patients from The University of Texas MD Anderson Cancer Center and performed the validation in another GWAS of 409 patients from the Nurses' Health Study and Health Professionals Follow-up Study, in which 95/858 (11·1%) and 48/409 (11·7%) patients died of cutaneous melanoma, respectively.

RESULTS

We identified two independent SNPs (MTHFD1 rs1950902 G>A and ALPL rs10917006 C>T) to be associated with CMSS in both datasets, and their meta-analysis yielded an allelic hazards ratio of 1·75 (95% confidence interval 1·32-2·32, P = 9·96 × 10^-5 ) and 2·05 (1·39-3·01, P = 2·84 × 10^-4 ), respectively. The genotype-phenotype correlation analyses provided additional support for the biological plausibility of these two variants' roles in tumour progression, suggesting that variation in SNP-related mRNA expression levels is likely to be the mechanism underlying the observed associations with CMSS.

CONCLUSIONS

Two possibly functional genetic variants, MTHFD1 rs1950902 and ALPL rs10917006, were likely to be independently or jointly associated with CMSS, which may add to personalized treatment in the future, once further validated. What is already known about this topic? Existing data show that survival rates vary among patients with melanoma with similar clinical characteristics; therefore, it is necessary to identify additional complementary biomarkers for melanoma-specific prognosis. A hypothesis-driven approach, by pooling the effects of single-nucleotide polymorphisms (SNPs) in a specific biological pathway as genetic risk scores, may provide a prognostic utility, and genetic variants of genes in folate metabolism have been reported to be associated with cancer risk. What does this study add? Two genetic variants in the folate metabolic pathway genes, MTHFD1 rs1950902 and ALPL rs10917006, are significantly associated with cutaneous melanoma-specific survival (CMSS). What is the translational message? The identification of genetic variants will make a risk-prediction model possible for CMSS. The SNPs in the folate metabolic pathway genes, once validated in larger studies, may be useful in the personalized management and treatment of patients with cutaneous melanoma.

Molecular characterization, expression pattern and evolution of nine suppressors of cytokine signaling (SOCS) gene in the swamp eel (Monopterus albus)

Suppressors of cytokine signaling (SOCS) family members have negative effects on cytokine signaling pathways involved in immunity, growth and development. Owing to their typical feature, they have been extensively studied in mammalians, but they have not offered systematic studies among teleosts. In the present study, nine SOCS family genes were identified in the swamp eel genome and analyzed regulation mechanisms of SOCS family members in swamp eels. The open reading frames of MaSOCS1a, MaSOCS1b, MaSOCS2, MaSOCS3a, MaSOCS3b, MaSOCS4, MaSOCS5, MaSOCS6 and MaSOCS7 were 663 bp, 603 bp, 717 bp, 618 bp, 645 bp, 1188 bp, 1488 bp, 1611 bp and 1998 bp and encoded 220, 238, 200, 205, 214, 395, 496, 536 and 655 amino acids, respectively. All SOCS proteins have no signal peptides. Multiple alignment revealed that MaSOCS family members possessed a typical conserved SOCS box and SH2 region. Phylogenetic analyses showed that all SOCS proteins were divided into two main clusters. Taken together with the similarity and identity of SOCS protein amino acids, these results indicated that MaSOCS family members shared conserved with other homologous genes, in which MaSOCS7 was more conserved. Further syntenic analysis confirmed the phylogenetic analysis results and annotation of SOCS protein, suggesting that MaSOCS5 shared a common ancestor gene with that of fish and humans. MaSOCS family members were constitutively expressed in a wide range of tissues with different levels. In particular, spleen and head kidneys play an important role in immune-related pathways. After Aeromonas veronii and polyinosinic-polycytidylic acid (poly I:C) challenge in the spleen and head kidney, MaSOCS family members exhibit different expression profiles. These expression patterns indicated that MaSOCS family members could make acute responses after pathogen invasion. Taken together, these results indicate that MaSOCS family members participate in the immune response against pathogens and offer a solid foundation for future studies of SOCS function.

Upregulation of long non-coding RNA HNF1A-AS1 is associated with poor prognosis in urothelial carcinoma of the bladder

OBJECTIVE

Long noncoding RNAs (lncRNAs) play important roles in the pathogenesis of bladder cancer. A recent study reported that lncRNA HNF1A-AS1 (HNF1A-AS1) was upregulated in urothelial carcinoma of the bladder (UCB) and served as a tumor promoter. However, the clinical significance of HNF1A-AS1 in the prognosis of patients with UCB was poorly understood. This work was designed to investigate the relationship between HNF1A-AS1 expression level and the prognosis of UCB.

PATIENTS AND METHODS

Relative expression levels of HNF1A-AS1 in UCB tissues were determined by qRT-PCR. Then, the associations between HNF1A-AS1 expression and clinical pathological parameters were further evaluated. Survival and Cox proportional-hazards regression analyses were performed to determine the correlation between HNF1A-AS1 expression levels and prognosis in the patients.

RESULTS

Data showed that the majority of UCB tissues showed higher HNF1A-AS1 levels than the corresponding normal tissues controls (p < 0.01). Statistical assay revealed that high HNF1A-AS1 expression was significantly correlated with histological grade (p = 0.008), tumor stage T (p = 0.003) and lymph nodes metastasis (p = 0.007). In addition, the overall survival time of patients with high HNF1A-AS1 expression was significantly shorter compared to those with low HNF1A-AS1 expression. Furthermore, multivariate analysis confirmed that relative HNF1A-AS1 expression was an independent predictor of overall survival in patients with UCB.

CONCLUSIONS

HNF1A-AS1 expression was upregulated in UCB, and it may be a useful prognostic biomarker for patients with UCB.