The Association between Dietary Magnesium Intake and Telomere Length in Adults with Hypertension

BACKGROUND

Dietary micronutrients are significantly associated with telomere length, as shown in multiple studies. However, no study has investigated the association between magnesium intake and telomere length in adults with hypertension.

METHODS

Participants were included from the National Health and Nutrition Examination Survey (NHANES) in 1999-2000 and 2001-2002. Dietary magnesium intake was assessed using the 24 - hour recall method and the telomere length of leukocytes was measured using polymerase chain reaction (PCR). A multivariate regression model was then used to assess the association between dietary magnesium intake and telomere length in adults with hypertension.

RESULTS

Our final analysis included 2199 hypertensive adults (46.79% males) with a mean dietary magnesium intake of 254.82±133.47 mg/day. Linear regression, adjusted for race, sex, age, smoking, uric acid, and other variables, showed that every 1 mg increase in dietary magnesium intake was associated with a 0.20 (95% CI: 0.01, 0.39, p = 0.043) longer telomere length in all participants. In the ≥45 years age group, there was a statistically significant association between the telomere length and dietary magnesium (95% CI: 0.16, 0.63, p <0.001).

CONCLUSIONS

This study suggests that increased magnesium intake is associated with a longer telomere length in hypertensive adults, especially in those ≥45 years of age. However, further research is needed to determine a causal relationship.

Measurement of the Sixth-Order Cumulant of Net-Proton Multiplicity Distributions in Au+Au Collisions at sqrt[s_{NN}]=27, 54.4, and 200 GeV at RHIC

According to first-principle lattice QCD calculations, the transition from quark-gluon plasma to hadronic matter is a smooth crossover in the region μ_{B}≤T_{c}. In this range the ratio, C_{6}/C_{2}, of net-baryon distributions are predicted to be negative. In this Letter, we report the first measurement of the midrapidity net-proton C_{6}/C_{2} from 27, 54.4, and 200 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). The dependence on collision centrality and kinematic acceptance in (p_{T}, y) are analyzed. While for 27 and 54.4 GeV collisions the C_{6}/C_{2} values are close to zero within uncertainties, it is observed that for 200 GeV collisions, the C_{6}/C_{2} ratio becomes progressively negative from peripheral to central collisions. Transport model calculations without critical dynamics predict mostly positive values except for the most central collisions within uncertainties. These observations seem to favor a smooth crossover in the high-energy nuclear collisions at top RHIC energy.

[Molecular characteristics of Legionella pneumophila in shower water of public places in Ma'anshan city from 2019 to 2020]

Objective: To understand the epidemiological and pathogenic characteristics of Legionella pneumophila in shower water of public places in Ma'anshan City from 2019 to 2020, and to provide scientific basis for further prevention and control of legionellosis. Methods: From 2019 to 2020, according to population density distribution and business scale of bathing places in the main urban area of Ma'anshan City (Huashan District and Yushan District), 8 public bathing places (including 3 large, 3 medium and 2 small) were selected to collect 308 shower water and water storage pool water samples (294 shower water samples and 14 water storage pool water samples). After the collected water samples were treated, cultured, isolated and identified, the type characteristics of Legionella pneumophila were analyzed. Results: Legionella pneumophila were detected in 120 water samples among 308 shower water and water storage pool water samples, with an overall positive rate of 39.0% (120/308). A total of 154 Legionella pneumophila strains were detected, including 10 different serotypes, predominated by serotype 1 (LP1) and serotype 3 (LP3), accounting for 40.9% (63/154) and 22.7% (35/154). Among 154 strains of Legionella pneumophila, 23 strains of Legionella pneumophila were positive for all 14 virulence genes, accounting for 14.9% (23/154), including 19 serotype 1 (LP1) and 4 serotype 8 (LP8). Pulsed field gel electrophoresis (PFGE) cluster analysis of 154 Legionella pneumophila strains showed 60 different patterns. Conclusion: Legionella pneumophila was seriously polluted in the shower water environment of public places in Ma^, anshan City. The serotypes are widely distributed and the virulence of the strains is strong. The results of molecular typing show that these strains have genetic diversity.

[The prevalence, influencing factors and prognosis of abnormal serum potassium levels in patients with chronic kidney disease]

Objective: To estimate the prevalence of hyperkalemia and hypokalemia in patients with chronic kidney disease (CKD), analyze the influencing factors and explore the impact on disease prognosis. Methods: A total of 3 190 patients with CKD stage 1-4 from 39 tertiary clinical centers in China between November 2011 and December 2016 were recruited. The baseline characteristics of the patients were collected through face-to-face questionnaire investigation, physical examination and laboratory test. Meanwhile, the data of patient's end-stage renal disease, cardiovascular disease events and deaths were obtained up to December 2017 through active monitoring. The patients were categorized into three groups based on their baseline level of serum potassium (hypokalemia:<3.5 mmol/L, normal range: 3.5-<5.0 mmol/L, hyperkalemia: ≥5 mmol/L). Multi-nominal logistic regression was employed to evaluate the association between clinical characteristics and the presence of hyperkalemia or hypokalemia. The competing risk-based subdistribution Cox proportional hazards regression was used to assess the association between baseline level of serum potassium and various outcomes. Results: The mean age of the patients was (50±14) years, with a male rate of 57.6% (1 839/3 190) and a majority of glomerulonephritis (59.7%, 1 668/2 792). Patients with CKD stage 3-4 accounted for 70.8% (2 260/3 190), and the mean level of serum potassium was (4.4±0.7) mmol/L. The prevalence of hypokalemia and hyperkalemia was 3.7% (n=118) and 17.6% (n=561), respectively. In the multivariable adjusted analysis, presence of history of cardiovascular disease (OR=0.33, 95%CI: 0.13-0.83, P=0.019) and estimated glomerular filtration rate (OR=0.95, 95%CI: 0.91-0.98, P=0.001) were inversely associated with hypokalemia, while use of thiazide or loop diuretic (OR=2.06, 95%CI: 1.51-2.81, P<0.001) and estimated glomerular filtration rate (OR=1.13, 95%CI: 1.12-1.16, P<0.001) were positively associated with hyperkalemia. After adjusting for relevant cardiovascular and renal risk factors, the result only showed a significant association between hypokalemia and risk of all-cause mortality (HR=2.12, 95%CI: 1.06-4.24, P=0.034). Conclusions: Hypokalemia and hyperkalemia were not rare in patients with CKD in China, with the latter more prevalent. Hypokalemia was independently associated with the risk of death.

Validity of near-infrared light transillumination for the assessment of proximal caries in permanent teeth

PURPOSE

The aim of this study was to evaluate the performance of DIAGNOcam (DC) in diagnosing proximal caries and to compare its effectiveness with the International Caries Detection and Assessment System (ICDAS) and bitewing radiography (BWR).

METHODS

118 premolars extracted for orthodontic reasons were included and examined using three detection methods and validated by histological sections as the gold standard. The sensitivity, specificity and areas under the ROC curve (Az value) at the outer half enamel (D1), inner half enamel (D2) and dentine (D3) thresholds were compared between different methods.

RESULTS

At all categories, the specificity of DC was almost as high as ICDAS and BWR. DC showed a significantly higher sensitivity (0.68) than both visual (0.33) and radiographic examination (0.47) at the D1 threshold. DC presented the highest Az value (area under the ROC curve) at the D1 and D2 threshold (0.81, 0.86), while BWR showed the greatest Az values at D3 (0.94). Furthermore, DC had the highest association strength with the gold standard (Spearman's ρ = 0.80).

CONCLUSIONS

It can be concluded that DC could detect proximal caries effectively and showed comparable or even better performance than ICDAS and BWR.

Transcriptome analysis of oviduct in laying ducks under different stocking densities

1. High stocking densities can lead to animal stress responses and lead to changes in bird behaviour, egg production and the fertility of laying birds. The oviduct plays a crucial role during the process of laying eggs. Therefore, it is essential to know how high stocking density affects oviduct function.2. In this study, a total of 2,115 differentially expressed genes (DEGs) were identified in duck oviduct tissues between different stocking density groups. These genes are mainly enriched in membrane components, calcium ion binding, cytokine-cytokine receptor interaction and focal adhesion. These pathways were closely related to the formation of eggs. This indicated that secretion and material transport functions of the oviduct are affected under high-density stocking. Further analysis showed that a total of 408 genes related to the transportation process were expressed in the oviduct, of which 96 genes were differentially expressed (LogFC≥1, P < 0.05). Forty-two of these DEGs belonged to the solute carrier family. The data showed that the expression of 31 transcripts was different between the two density groups. Expression of KCNJ15, SLC26A8, and TRPM5 was only seen in the high-density group (8/m²), while ATP13A3 and KCNIP2 were only expressed in the low-density group (4/m²).3. Consequently, high stocking density may affect the expression and splicing of genes related to molecular transport in the oviduct.

[The study of the impact by atractylenolide-1 on inflammatory cytokine, autophagy and apoptosis in alveolar macrophages of silicosis patients]

Objective: To explore the effect of atractylenolide-1 (ATL-Ⅰ) on alveolar macrophages in silicosis patients. Methods: In December 2019, 12 male silicosis patients treated in Beidaihe Sanatorium for Chinese Coal Miners from July to September 2019 were selected by random sampling. Their alveolar macrophages were collected and divided into control group, ATL-Ⅰ group (100 μmol/L) and dimethyl sulfoxide (DMSO) group (100 μmol/L) . The exprossion levels of inflammatory factor interleukin-1β (IL-1β) , interleukin-6 (IL-6) , tumor necrosis factor α (TNF-α) were detected by enzyme-linked immunosorbent assay. The expression levels of autophagy associated protein microtubule associated protein light chain 3 (LC3) , autophagy substrate protein p62, lysosome associated membrane protein 2 (LAMP2) , apoptosis associated protein Cleaved caspase-3, nuclear factor kappa B (NF-κB) and its phosphorylated form (p-NF-κB) were detected by Western blot. Results: Compared with the control group and DMSO group, the expression levels of IL-1β, IL-6, TNF-α in alveolar macrophages decreased significantly in the ATL-Ⅰ group (P<0.05) , and the expression levels of p-NF-κB, the ratio of LC3-Ⅱ/LC3-Ⅰ also decreased significantly in the ATL-Ⅰ group (P<0.05) . However, the expression levels of NF-κB, LAMP2, p62 and Cleaved caspase-3 in the ATL-Ⅰ group were not statistically different from those in the control group and DMSO group (P>0.05) . There was no statistically significant differences in the expression of the above indexes between the control group and DMSO group (P>0.05) . Conclusion: ATL-Ⅰ may reduce the release of inflammatory factors from alveolar macrophages and inhibit the activity of autophagy in silicosis patients, but it may not reduce the level of apoptosis.

[Screening results and genetic analysis of neonatal tetrahydrobiopterin deficiency in Hainan Province from 2007 to 2019]

A total of 1 295 516 dried blood spots were collected from newborns in Hainan Province from 2007 to 2019 who participated in the screening of neonatal diseases, and 43 cases of hyperphenylalaninemia were diagnosed. Among the 43 cases, 8 cases were confirmed to have tetrahydrobiopterin deficiency (4 males and 4 females). The incidence of tetrahydrobiopterin deficiency among newborns in Hainan Province was 6.2/1 million. Six mutations in the PTS gene were detected among 7 cases; the mutations were as follows: c.317C>T, c.286G>A, c.259C>T, c.155A>G, c.84+291A>G and c.83+1777T>G. A homozygous mutation at c.41T>C site of QDPR gene was detected in one case. Overall, it's found that the incidence of tetrahydrobiopterin deficiency in newborn populations in Hainan Province is low, and PTS gene mutations account for the largest proportion of cases of tetrahydrobiopterin deficiency within the study population.

Clinical efficacy of palbociclib-based therapy in women with HR+/HER2- metastatic breast cancer in the real-world setting for Chinese women: a comparison with the IRIS study

OBJECTIVE

This retrospective study aimed to explore the clinical efficacy of palbociclib with endocrine therapy (ET) in women with hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer in real-world practice.

PATIENTS AND METHODS

This retrospective study analyzed the medical records of patients to determine treatment outcomes. Progression-free survival (PFS) curves were generated using log-rank tests with the Kaplan-Meier method. Treatment outcomes in Chinese patients were compared with those in patients from the USA, Argentina, Canada, and Europe in the IRIS study.

RESULTS

In total, 69 patients were included in this study. The median PFS was 12.8 months (95% confidence interval: 10.1-15.5). A longer PFS was observed for patients with bone-only metastases, no liver metastases, no previous palliative chemotherapy, no previous palliative ET, and ET sensitivity. The overall response rate was 10.1%, and the clinical benefit rate was 78.3%. Nineteen patients (27.5%) received a reduced dose of palbociclib according to the decision of their physicians. Dose reduction did not affect the clinical efficacy of the combined treatment. Compared with those in the IRIS study, Chinese patients receiving palbociclib-based treatment were younger, and they had fewer bone-only metastases and more visceral and liver metastases. The clinical benefit rate and overall response rate for Chinese patients were lower than those observed for the patients in the IRIS study.

CONCLUSIONS

ET combined with palbociclib treatment was effective and well-tolerated in HR+/HER2- metastatic breast cancer patients in the real-world setting. Earlier use of palbociclib-ET was associated with more clinical benefits in HR+/HER2- metastatic breast cancer.

Study on the effects of quercetin on brain cell apoptosis and HMGB-1 and TLR-4 level in rats with encephalitis

OBJECTIVE

To explore the therapeutic effects of quercetin on rats with encephalitis, especially on cell apoptosis, and the levels of HMGB-1 and TLR-4.

MATERIALS AND METHODS

32 healthy rats were equally assigned into ZC group (healthy group), NY group (encephalitis group), DJ group (60 ml quercetin group), and GJ group (240 ml quercetin group) followed by analysis of cell apoptosis, brain tissue water content, neurons, HMGB-1, TLR-4 and other inflammatory factors.

RESULTS

The ZC group showed normal neuron volume and equitable staining; compared with ZC group, NY group showed neuron volume shrinkage and chromatin condensation; the neuron and color in DJ group were slightly better than NY group; the neuron volume in GJ group increased significantly and chromatin is distributed evenly. TLR-4, IL-4, IL-6, HMGB-1 in ZC and DJ group were significantly lower than those in NY group (p<0.05); IL-4, IL-6, HMGB-1 in GJ group significantly decreased compared with DJ group (p<0.05); MMP-9 enzyme activity in ZC and DJ group was significantly lower than NY group (p<0.05) with lower level in GJ group than DJ group (p<0.05). The water content was higher in brain tissue of NY group than ZC group (p<0.05) and lower in DJ group than NY group (p<0.05) with lower level in GJ group than DJ and NY group (all p<0.05). The hippocampal neurons and cortical neurons in ZC and DJ group were higher than those in NY group (p<0.05) and elevated in GJ group compared with DJ group and NY group (p<0.05).

CONCLUSIONS

Quercetin is effective in treating encephalitis rats possibly through inhibition of neuronal cell apoptosis and level of HMGB-1 and TLR-4.

Association of Polymorphisms of Glutamate Cysteine Ligase Genes GCLC C-129 T and GCLM C-588 T with Risk of Polycystic Ovary Syndrome in Chinese Women

Polycystic ovary syndrome (PCOS) is generally considered a multifactorial disease caused by interactions between multiple susceptible genes and environmental factors. Glutamate cysteine ligase (GCL) is the rate-limiting enzyme in glutathione biosynthesis. This study examined the relationship between single nucleotide polymorphisms (SNPs) in the GCL catalytic subunit (GCLC C-129 T) and the modifier subunit (GCLM C-588 T) and PCOS. The two SNPs were genotyped in 1017 PCOS patients and 793 control women. Clinical, metabolic, hormonal, and oxidative stress parameters were also assessed. The frequencies of the CT + TT genotypes (21.6% vs. 27.7%) and T allele (11.5% vs. 14.7%) of SNP GCLC C-129 T were significantly lower in hyperandrogenism (HA)-PCOS patients than in control women. Logistic regression analysis revealed that the relative hazard of HA-PCOS was lower in individuals with the -129 T allele (CT + TT genotypes) than in those with the CC genotype (OR = 0.723, 95% CI: 0.571-0.915, P = 0.007). When using the GCLC-CC/GCLM-CC combined genotype as the reference category, the GCLC-CT + TT/GCLM-CC combined genotype was a protective factor for PCOS with HA (OR = 0.743, 95% CI: 0.566-0.976, P = 0.033). HA-PCOS patients with the -129 T allele had lower waist circumference, waist-to-hip ratio, and body mass index (BMI) and lower fasting insulin concentration and homeostatic model assessment of insulin resistance after correcting for age and BMI (P < 0.05). The T allele of SNP GCLC C-129 T and its combination with the CC genotype of SNP GCLM C-588 T are associated with decreased risk of HA-PCOS in Chinese women.

[Multi-level scanning of environmental factors of body mass index of children and adolescents aged 7-17 years in China]

Objective: To investigate the influence of environmental factors on body mass index of children and adolescents in China. Methods: Using data from the China Health and Nutrition Survey, the research object to 7 - 17 years old children and adolescents who participated in 2000, 2006, 2011, and 2015 round of survey with complete data, a total of 6 626 children and adolescents (male 3 473, female 3 153) were investigated under univariate analysis for each environmental factor variable before using Partial Least Square Regression fitting a linear model for further screening. Finally, we fitted a three-level linear mixed-effects model distinct by urban and rural area for analysis. Results: The three-level null model, log likelihood=-17 034.68, χ²=483.06, P<0.001. Intern-class correlation coefficient (ICC) showed that community-level was 9.97%, and both community and individual were 39.38%. The three-level model also showed that urban model's urbanization index (β=-0.05, 95%CI: -0.09--0.01, P<0.05), the park location (β=-0.88, 95%CI: -1.72 - -0.04, P<0.05), 15 - 17 age group (β=-1.04, 95%CI:-1.78 - -0.30, P<0.05) were negatively correlated with BMI. The distance to the gym (β=0.12, 95%CI: 0.02 - 0.22, P<0.05), the number of home TV sets (β=0.50, 95%CI: 0.08 - 0.92, P<0.05) and the frequency of parents' alarm of fiction TV program contents (β=1.85, 95%CI: 0.70 - 3.00, P<0.05) were correlated with BMI. Rural urbanization index (β=-0.04, 95%CI:-0.07 - -0.01, P<0.05). Rural per capita income (β=-7.29e^-4, 95%CI:-1.00e^-3 - -6.77e^-5, P<0.05), parents' restricted frequency of watching TV (β=-1.29, 95%CI:-2.36 - -0.21, P<0.05), adipo-energy ratio (β=-0.03, 95%CI:-0.06 - -1.00e^-3, P<0.05) were negatively correlated with the BMI. Factors as the frequency of parents' alarm of fiction TV program contents (β=3.01, 95%CI: 0.03 - 6.00, P<0.05), the survey time was 2015 (β=4.83, 95%CI: 1.96 - 7.69, P<0.05) were correlated with BMI. Conclusions: Environmental factors could indirectly influence the change of BMI of children and adolescents to different degrees and various aspects. Urbanization index and rural per capita income had a slight protective effect on increasing BMI of children and adolescents. At the community level, attention should be paid to the setting of activity places around the living environment of children and adolescents. Family members should also guide their children and adolescents to develop nice behavior in watching TV.

P02.03 Automated cell type specific PD-L1 quantification by artificial intelligence using high throughput bleach & stain 15-marker multiplex fluorescence immunohistochemistry in human cancers

Background

The quantification of PD-L1 (programmed cell death ligand 1) has been used to predict patient’s survival, to characterize the tumor immune microenvironment, and to predict response to immune checkpoint therapies. However, a framework to assess the PD-L1 status with a high interobserver reproducibility on tumor cells and different types of immune cells has yet to be established.

Materials and Methods

To study the impact of PD-L1 expression on the tumor immune microenvironment and patient outcome, a framework for fully automated PD-L1 quantification on tumor cells and immune cells was established and validated. Automated PD-L1 quantification was facilitated by incorporating three different deep learning steps for the analysis of more than 80 different neoplasms from more than 10’000 tumor specimens using a bleach & stain 15-marker multiplex fluorescence immunohistochemistry panel (i.e., PD-L1, PD-1, CTLA-4, panCK, CD68, CD163, CD11c, iNOS, CD3, CD8, CD4, FOXP3, CD20, Ki67, CD31). Clinicopathological parameter were available for more than 30 tumor entities and overall survival data were available for 1517 breast cancer specimens.

Results

Comparing the automated deep-learning based PD-L1 quantification with conventional brightfield PD-L1 data revealed a high concordance in tumor cells (p<0.0001) as well as immune cells (p<0.0001) and an accuracy of the automated PD-L1 quantification ranging from 90% to 95.2%. Across all tumor entities, the PD-L1 expression level was significantly higher in distinct macrophage/dendritic cell (DC) subsets (identified by CD68, CD163, CD11c, iNOS; p<000.1) and in macrophages/DCs located in the Stroma (p<0.0001) as compared to intratumoral macrophages/DC subsets. Across all different tumor entities, the PD-L1 expression was highly variable and distinct PD-L1 driven immune phenotypes were identified based on the PD-L1 intensity on both tumor and immune cells, the distance between non-exhausted T-cell subsets (i.e. PD-1 and CTLA-4 expression on CD3+CD8+ cytotoxic T-cells, CD3+CD4+ T-helper cells, CD3+CD4+FOXP3+ regulatory T-cells) and tumor cells as well as macrophage/(DC) subtypes. In breast cancer, the PD-L1 fluorescence intensity on tumor cells showed a significantly higher predictive performance for overall survival with an area under receiver operating curves (AUC) of 0.72 (p<0.0001) than the percentage of PD-L1+ tumor cells (AUC: 0.54). In PD-L1 positive as well as negative breast cancers a close spatial relationship between T- cell subsets (CD3+CD4±CD8±FOXP3±PD-1±CTLA-4±) and Macrophage/DC subsets (CD68±CD163±CD11c±iNOS) was found prognostic relevant (p<0.0001).

Conclusions

In conclusion, multiplex immunofluorescence PD-L1 assessment provides cutoff-free/continuous PD-L1 data which are superior to the conventional percentage of PD-L1+ tumor cells and of high prognostic relevance. The combined analysis of spatial PD-L1/PD-1 data and more than 20 different immune cell subtypes of the immune tumor microenvironment revealed distinct PD-L1 immune phenotypes.

Disclosure Information

N.C. Blessin: None. E. Bady: None. T. Mandelkow: None. C. Yang: None. J. Raedler: None. R. Simon: None. C. Fraune: None. M. Lennartz: None. S. Minner: None. E. Burandt: None. D. Höflmayer: None. G. Sauter: None. S.A. Weidemann: None.

An arthroscopic technique for closure of perforations in temporomandibular joint retrodiscal tissues

The objective of this retrospective study was to introduce and evaluate an arthroscopic discopexy for closure of retrodiscal tissue perforations. A total of 112 patients (135 joints) receiving an arthroscopic discopexy for management of retrodiscal tissue perforations between January 2016 and September 2019 were included. Pre- and postoperative visual analogue scale (VAS) pain scores and maximum inter-incisal opening (MIO), as well as magnetic resonance imaging (MRI) data, were collected and analysed. Success was recorded when the disc position was >11 o'clock, VAS pain score <3, and MIO>25 mm. For patients with a condyle deformity, postoperative bone remodelling was also recorded. The VAS pain score decreased from 3.04 ± 2.66 preoperatively to 0.88 ± 1.13 at 12 months postoperatively (P < 0.001) and MIO increased from 33.90 ± 7.39 mm to 35.19 ± 6.14 mm (P = 0.029). MRI evaluation revealed that 133 discs were successfully repositioned back on top of the condyle. Among these, 11 joints were associated with either VAS pain score ≥3 or MIO ≤25 mm. Therefore, a success rate of 90.4% (122/135) was achieved at 12 months postoperative. Bone remodelling was detected in 72 joints. Arthroscopic discopexy is a minimally invasive and effective treatment for retrodiscal tissue perforations that achieves the purpose of simultaneously restoring the intra-articular structures and relieving clinical symptoms.

The detection of SAS1B in serum provides clues for early diagnosis of thyroid cancer

OBJECTIVE

The incidence of thyroid cancer is rising globally. Most patients progress slowly, but some patients develop lymph node and distant metastasis earlier, and their prognosis is poor. Therefore, early diagnosis and warning of malignancy are very meaningful for such patients. SAS1B gene is a newly discovered protein expressed on the surface of mature egg cells and has metalloendopeptidase activity. We aimed at exploring whether SAS1B is involved in the occurrence of thyroid cancer, and at providing evidence for early diagnosis and targeted therapy of thyroid cancer.

PATIENTS AND METHODS

In this study, a rabbit anti-human SAS1B polyclonal antibody was prepared by gene recombination technology. The indirect ELISA method was used to detect the SAS1B protein expression in the serum of 69 patients with thyroid cancer and 55 normal controls, and the relevant pathological factors were analyzed. Immunohistochemistry and PCR technology were used to investigate the expression levels of SAS1B protein and mRNA in 30 thyroid cancer tissues and 23 control thyroid tissues.

RESULTS

The titer of SAS1B recombinant antibody was 1:51200. The expression of SAS1B in the serum of patients with thyroid cancer was higher than that in the normal control group (p<0.01). The antibody had a good sensitivity in serum detection of cancer patients (p=0.008<0.01), the linear regression analysis result was that the expression of SAS1B gene was related to tumor envelope invasion and lymph node metastasis (p=0.003<0.01, p=0.003<0.01), and it was irrelevant to the patient's gender, age, tumor mass size, number of cancer foci, pathological stage, etc. (p>0.05). The results of immunohistochemistry showed that SAS1B protein was mainly located in the cytoplasm and membrane of thyroid cancer cells. The expression intensity in thyroid cancer tissues was higher than that in control tissues (p<0.05), but it was not expressed in normal thyroid tissues. Antibodies showed a good sensitivity that was used to detect thyroid cancer tissues (p=0.000<0.01). The results of ordinary PCR detection using thyroid cancer tissue and control thyroid tissue showed that the amplification products of the three domains (N-terminal, C-terminal and catalytic domain) of the SAS1B gene showed high expression in thyroid cancer tissue. q-PCR results showed that the expression of SAS1B gene in thyroid cancer and control thyroid tissue was higher than that in control group (p<0.05), and the genes of Aurora A and BARD1 related to centrosome replication and DNA replication forks protection during the proliferation were highly expressed in thyroid cancer tissue. The study results suggested that SAS1B was involved in the carcinogenesis of thyroid cancer. The Hum_mPLoc.2.0 software, PSORT Ⅱ software and UniProt software were used to predict that SAS1B protein had secretory protein properties.

CONCLUSIONS

The above data indicate that the SAS1B gene is closely related to the process of thyroid cancer and can serve as a good tumor marker that can be used for early diagnosis and early warning of thyroid malignancy.