No abstract

‘Huangguogan’ (Citrus reticulata × C. sinensis) is a new cultivar of mandarin citrus in China, and the research on fertilization of ‘Huangguogan’ is very limited. In this study, the effect of N fertilization on ‘Huangguogan’ fruit quality was determined at ripening. Sugars (sucrose, fructose, and glucose), organic acids (pyruvic, oxalic, citric acid, etc.), and vitamin components were measured at six stages of fruit development, and eight enzymes related to the glycolytic and Krebs cycle were assessed. The 1.81 kg N y-1 treatment group showed the highest total soluble solids concentration and total soluble solids/titratable acidity ratio but the lowest titratable acidity (acid content) at ripening, while the N1 treatment (0 kg N y-1) showed the opposite trend. Sucrose and citric acid accumulated to the largest extent during fruit development. Sucrose and ascorbic acid content increased (8.46 to 50.97 mg g-1 and 8.16 to 27.39 mg g-1, respectively), while citric acid content decreased (90.81 to 0.02 mg g-1). Aconitase was the key enzyme responsible for the observed changes in citric acid. The N concentrations in ripening fruit ranged from 2.25% to 4.15%. Curve estimation and principal component analysis revealed that fruit N was positively correlated with the sugars and vitamin components and negatively correlated with the organic acids. The accumulation of these metabolites seemed closely related to the dynamic changes in fruit N concentration at the five N levels tested. In conclusion, we suggest that the 1.81 kg N y-1 treatment represents the most suitable N fertilizer treatment for ‘Huangguogan’ citrus fruit.

Purpose Early and accurate preoperative diagnosis of central lymph node metastasis (CLNM) is crucial to improve surgical management of patients with clinical lymph node-negative papillary thyroid carcinoma (PTC). Towards improving diagnosis of CLNM, we assessed the value of combining preoperative clinical characteristics, conventional ultrasound, and contrast-enhanced ultrasound (CEUS) in preoperative prediction of CLNM of different sized PTCs. Patients and Methods Patients were divided according to tumor size: a PTC group (>10 mm) and a papillary thyroid microcarcinoma (PTMC) group (≤10 mm). We retrospectively analyzed the clinical and ultrasonographic features of 120 PTC patients and 165 PTMC patients. Multivariate logistic regression analysis was used to screen independent risk factors and establish prediction models. Receiver operating characteristic curves were used to determine the best cut-off values for continuous variables and assess the performance of prediction models. Results Independent risk predictors of CLNM for the PTC group were extrathyroidal extension in CEUS (OR=7.923), tumor size >14 mm (OR=5.491), and multifocality (OR=3.235). For the PTMC group, the independent risk factors were the distance from the thyroid capsule =0 mm (OR=4.629), male (OR=3.315), tumor size >5 mm (OR=3.304), and microcalcification (OR=2.560). The predictive model of combined method had better performance in predicting CLNM of PTC compared with models based on CEUS and conventional ultrasound alone (area under the curve: 0.832 vs 0.739, P =0.0011; 0.832 vs 0.678, P =0.0012). For PTMC, comparing with CEUS, the combined method and conventional ultrasound performed better than CEUS alone in predicting CLNM (area under the curve: 0.783 vs 0.636, P =0.0016; 0.738 vs 0.636, P =0.0196). Conclusion The predictive models of combined method obtained from significant preoperative clinical and ultrasonographic features can potentially improve the preoperative diagnosis and individual treatment of CLNM in patients with PTC and PTMC. CEUS may be helpful in predicting CLNM of PTC, but CEUS would be ineffective in predicting CLNM of PTMC.

ObjectiveThis study aims to investigate the value of contrast-enhanced ultrasound (CEUS) in the differential diagnosis and risk stratification of ACR TI-RADS category 4 and 5 thyroid nodules with non-hypovascular.MethodsFrom January 2016 to December 2019 in our hospital, 217 ACR TI-RADS category 4 and 5 nodules with non-hypovascular in 210 consecutive patients were included for a derivation cohort. With surgery and/or fine-needle aspiration (FNA) as a reference, conventional ultrasound (US) features and CEUS features were analyzed. Multivariate logistic regression analysis was used to screen the independent risk factors and establish a risk predictive model. Between January 2020 and March 2021, a second cohort of 100 consecutive patients with 101 nodules were included for an external validation cohort. The model was converted into a simplified risk score and was validated in the validation cohort. The area under the receiver operating characteristic curves (AUC) were used to assess the models’ diagnostic performance.ResultsMicro-calcification, irregular margin, earlier wash-out, centripetal enhancement, and absence of ring enhancement were independent risk factors and strongly discriminated malignancy in the derivation cohort (AUC = 0.921, 95% CI 0.876–0.953) and the validation cohort (0.900, 0.824–0.951). There was no significant difference (P = 0.3282) between the conventional US and CEUS in differentiating malignant non-hypovascular thyroid nodules, but a combination of them (the predictive model) had better performance than the single method (all P <0.05), with a sensitivity of 87.0%, specificity of 86.2%, and accuracy of 86.6% in the derivation cohort. The risk score based on the independent risk factors divided non-hypovascular thyroid nodules into low-suspicious (0–3 points; malignancy risk <50%) and high-suspicious (4–7 points; malignancy risk ≥ 50%), the latter with nodule ≥10mm was recommended for FNA. The risk score showed a good ability of risk stratification in the validation cohort. Comparing ACR TI-RADS in screening suitable non-hypovascular nodules for FNA, the risk score could avoid 30.8% benign nodules for FNA.ConclusionsCEUS is helpful in combination with conventional US in differentiating ACR TI-RADS category 4 and 5 nodules with non-hypovascular. The risk score in this study has the potential to improve the diagnosis and risk stratification of non-hypovascular thyroid nodules.

Objective: Osimertinib is the 3rd generation EGFR inhibitor, which has been approved for the treatment of NSCLC patients with EGFRT790M. More recently, a tertiary EGFRC797S mutation was reported as the dominant resistance (40~20%) mechanism to Osimertinib. The emergence of C797S mutation prevent covalent bond formation with Osimertinib, and caused the drug resistance. So, it’s an urgent demand for new EGFR inhibitors that can effectively inhibit EGFR triple mutant, d746-750/T790M/C797S & L858R/T790M/C797S. Here, we disclose our clinical candidate, TQB3804, as a novel 4th generation inhibitor that potently inhibits triple mutants. Methods: The enzyme activities of TQB3804 for EGFRd746-750/T790M/C797S, EGFRL858R/T790M/C797S, EGFRd746-750/T790M, EGFRL858R/T790M, and EGFRWT were measured with corresponding kinase assays. The anti-proliferative activity was evaluated in Ba/F3 (EGFRd746-750/T790M/C797S), NCI-H1975 (EGFRd746-750/T790M/C797S), PC9 (EGFRd746-750), and A431 (EGFRWT) cell lines, and the phosphorylation of EGFR was also evaluated in Ba/F3 (EGFRd746-750/T790M/C797S) cell line. Antitumor activity of TQB3804 was evaluated in three triple mutant cell-derived tumor xenograft (CDX) models Ba/F3 (EGFRd746-750/T790M/C797S), NCI-H1975 (EGFRd746-750/T790M/C797S), and PC9 (EGFRd746-750/T790M/C797S) and one Osimertinib resistant patient-derived xenograft (PDX) model of NSCLC (LUPF104, EGFRd746-750/T790M/C797S). Results: TQB3804 displayed potent enzymatic activities for EGFRd746-750/T790M/C797S, EGFRL858R/T790M/C797S, EGFRd746-750/T790M, and EGFRL858R/T790M with IC50 of 0.46, 0.13, 0.26, and 0.19 nM respectively, and has similar enzymatic activity for EGFRWT (IC50 = 1.07) to Osimertinib. It also showed expected anti-proliferative activity in 4 cell lines, Ba/F3 (EGFRd746-750/T790M/C797S), NCI-H1975 (EGFRd746-750/T790M/C797S), PC9 (EGFRd746-750), and A431 (EGFRWT), with IC50 of 26.8, 163, 45, and 147 nM, respectively. The phosphorylation for EGFR in Ba/F3 (EGFRd746-750/T790M/C797S) cell line was potently inhibited with IC50 =18.5 nM. TQB3804 significantly inhibited tumor growth in the triple mutant Ba/F3 (EGFRd746-750/T790M/C797S), NCI-H1975 (EGFRd746-750/T790M/C797S), and PC9 (EGFRd746-750/T790M/C797S) CDX models, as well as in the LUPF104 PDX model. Western blot analysis of the tumor samples in the Ba/F3 (EGFRd746-750/T790M/C797S) CDX model showed that TQB3804 inhibited p-EGFR, p-AKT and p-ERK indicating that the tumor growth inhibition was through inhibition of the resistant triple mutant EGFR. Conclusions: We have identified a potent orally active 4th generation EGFR inhibitor, TQB3804. It can inhibit the activity of Osimertinib resistant triple mutant EGFR, and showed strong antitumor activity in corresponding in vitro and in vivo preclinical assays. These results are considered highly promising and warrant moving the compound forward to clinical investigation. Citation Format: Xile Liu, Xiquan Zhang, Ling Yang, Xin Tian, Tiantian Dong, Charles Z Ding, Lihong Hu, Lingyu Wu, Lele Zhao, Jun Mao, Qusheng Ji, Shaoyu Yan, Zhenzhen Zhu, Yuanfeng Xia, Chichung Chan, Shuhui Chen. Preclinical evaluation of TQB3804, a potent EGFR C797S inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1320.