Characterization and transformation of TtMYB1 transcription factor from Tritipyrum to improve salt tolerance in wheat.

BACKGROUND: Common wheat (Triticum aestivum L.) is a worldwide cereal crop, which is an integral part of the diets of many countries. In addition, the MYB gene of wheat plays a role in the response to salt stress. RESULTS: "Y1805" is a Tritipyrum variety that is relatively tolerant to salt. We used transcriptome analysis to show that the "Y1805" MYB gene was both highly expressed and sensitive to salt stress. Compared with control roots, the level of MYB expression during salt stress was higher, which rapidly decreased to control levels during the recovery process. MYB gene relative expression showed the highest levels in "Y1805" roots during salt stress, with the stems and then leaves being the next highest stressed tissues. The novel MYB gene (TtMYB1) was successfully cloned from "Y1805". It showed a coding sequence length of 783 bp with 95.79% homology with Tel2E01G633100 from Thinopyrum elongatum. TtMYB1 and MYB from Th. elongatum were clustered in the same branch using phylogenetic analysis, which indicated high similarities. The TtMYB1 gene is located in the nucleus. The coleoptile method was employed when a TtMYB1 overexpression vector was used during transformation into "1718" (common wheat). Under high salt stress, TtMYB1 leaves of overexpression lines had decreased wilting, when compared with wild-type (WT) plants. During normal conditions, salt stress, and recovery, the lengths of the roots and the heights of seedlings from the overexpression lines were found to be significantly greater than roots and seedlings of WT plants. In addition, during high salt stress, the overexpression lines showed that proline and soluble sugar levels were higher than that of WT plants, but with lower malondialdehyde levels. Forty-three proteins that interacted with TtMYB1 were identified using the yeast two-hybrid assay. Protein-protein interaction analyses indicated that most were SANT domain-containing and Wd repeat region domain-containing proteins. Among these proteins, ribosomal proteins were the main node. Abiotic stress-related terms (such as "carbonate dehydratase activity", "protein targeting peroxisomes", and "glutathione peroxidase activity") were enriched in GO analysis. In KEGG analysis, "carbohydrate metabolism", "environmental information processing", "genetic information processing", "signaling and cell precursors", and "energy metabolism" pathways were enriched. CONCLUSION: The TtMYB1 gene might enhance salt tolerance by increasing proline and soluble sugar content and antioxidase activity in transgenic wheat. It therefore has the potential to enhance high salt tolerance in plants.

Midgut membrane protein BmSUH facilitates Bombyx mori nucleopolyhedrovirus oral infection.

Baculoviruses are virulent pathogens that infect a wide range of insects. They initiate infections via specific interactions between the structural proteins on the envelopes of occlusion-derived virions (ODVs) and the midgut cell surface receptors in hosts. However, host factors that are hijacked by baculoviruses for efficient infection remain largely unknown. In this study, we identified a membrane-associated protein sucrose hydrolase (BmSUH) as an ODV binding factor during Bombyx mori nucleopolyhedrovirus (BmNPV) primary infection. BmSUH was specifically expressed in the midgut microvilli where the ODV-midgut fusion happened. Knockout of BmSUH by CRISPR/Cas9 resulted in a significantly higher survival rate after BmNPV orally infection. Liquid chromatography-tandem mass spectrometry analysis and co-immunoprecipitation analysis demonstrated that PIF protein complex required for ODV binding could interact with BmSUH. Furthermore, fluorescence dequenching assay showed that the amount of ODV binding and fusion to the midgut decreased in BmSUH mutants compared to wild-type silkworm, suggesting the role of BmSUH as an ODV binding factor that mediates the ODV entry process. Based on a multilevel survey, the data showed that BmSUH acted as a host factor that facilitates BmNPV oral infection. More generally, this study indicated that disrupting essential protein-protein interactions required for baculovirus efficient entry may be broadly applicable to against viral infection.

Controllable non-uniformly distributed spiking cluster generation in broadband optoelectronic oscillator.

An approach to achieve controllable non-uniformly distributed spiking cluster generation is proposed and demonstrated based on an externally-triggered broadband optoelectronic oscillator (OEO). The theory of controlling the distribution of the spiking pulses in a spiking cluster is established. Based on the theory, the dynamic and the distribution characteristics are analyzed and revealed in the stable spiking oscillation state under different externally-injected trigger signal voltages. The peak-voltage envelop of the cluster and the interval of the spiking pulses are demonstrated to have an approximate negative linearity relationship with the externally-injected trigger signal voltage in both the numerical simulation and the experiment, where a square waveform, a trapezoidal waveform, a parabola waveform, and a half-sinusoidal waveform are used as the externally-injected trigger signals. The results indicate that the spiking pulse distribution in the generated spiking cluster can be well controlled through tuning the externally-injected trigger signal voltage. The proposed scheme can be utilized in spiking encoding and reservoir computing.

Phase-locked dual-frequency microwave signal generation in an optoelectronic oscillator based on frequency mixing mutual injection.

An approach to generating stable phase-locked dual-frequency microwave signals is proposed and demonstrated based on a dual-passband optoelectronic oscillator (OEO). Mode gain competition is broken by employing frequency mixing mutual injection effect to realize phase locking between the two oscillation signals, which is achieved by applying a single-tone signal to a microwave mixer in the OEO cavity. In addition, a dual-loop configuration with balanced detection is utilized to ensure a high side mode suppression ratio (SMSR) and ultra-low phase noise, which also enhances the stability of the generated signal. In the experiment, a phase-locked dual-frequency microwave signal at 9.9982 GHz and 10.1155 GHz is generated by using the proposed OEO scheme. The SMSR and the phase noise are 75 dB and -141 dBc/Hz@10 kHz, respectively. Additionally, the Allan deviation of the generated signal is in the order of 10-11@1 s. These parameters are superior to those based on the same OEO but with a single-loop configuration, which are also compared in detail.

Novel heptafluoroisopropyl N-phenylpyrazole aryl amides containing cyanoalkyl groups: Design, synthesis, insecticidal activity, docking studies and theoretical calculations.

To discover and develop new insecticides of the phenylpyrazole class, a series of heptafluoroisopropyl N-phenylpyrazole aryl amide compounds bearing cyanoalkyl groups were synthesized based on the lead compound nicofluprole. Their structures were established by HRMS, 1H NMR and 13C NMR. Bioassay results indicated that several of these compounds exhibited remarkable acaricidal and insecticidal activities. The LC50 values for compounds A1, A2 and A5 against Tetranychus cinnabarinus (T. cinnabarinus) were 1.7-4.2 times lower than that of nicofluprole (3.124 mg/L). Compounds A1, A2, A4 and A7 against Myzus persicae (M. persicae) had LC50 values of 0.261, 1.292, 0.589 and 1.133 mg/L respectively, exceeding that of nicofluprole (LC50 = 4.200 mg/L). Some compounds also demonstrated good insecticidal activity against Plutella xylostella (P. xylostella). For example, compounds A1-A4, A6, and A7 had a mortality rate of 100 % at a low concentration of 1.25 mg/L, which was comparable to nicofluprole (93.3%). Compound A1 exhibited insecticidal activity against Chilo suppressalis (C. suppressalis) with an LC50 value of 2.271 mg/L, which was superior to both nicofluprole (6.021 mg/L) and the positive control broflanilide (6.895 mg/L). Taking compound A5 as a representative, we tested the insecticidal activity against Aphis fabae (A. fabae), Aphis gossypii Glover (A. gossypii Glover), Nilaparvata lugens (N. lugens) and Laodelphax striatellus (L. striatellus) at 10 mg/L, and our results revealed that compound A5 exhibited broad-spectrum insecticidal activity. Molecular docking studies suggested that A1 had a lower binding energy of -7.764 kcal/mol with the P. xylostella gamma-aminobutyric acid receptors (GABAR). Density functional theory calculations (DFT) provided insights into the design of new compounds. This research suggested that the novel phenylpyrazoles featuring cyanoalkyl moieties in this work hold potential as novel insecticides for further research and development.

Juvenile hormone regulates silk gene expression by m6A RNA methylation.

Juvenile hormone (JH) is an indispensable insect hormone that is critical in regulating insect development and physiology. N6-methyladenosine (m6A) is the most abundant modification of RNA that regulates RNA fate in eukaryotic organisms. However, the relationship between m6A and JH remains largely unknown. Here, we found that the application of a Juvenile hormone analog (JHA) extended the larval period of Bombyx mori and increased the weight and thickness of the cocoon. Interestingly, global transcriptional patterns revealed that m6A-related genes are specifically regulated by JHA in the posterior silk gland (PSG) that synthesizes the major component of cocoon silk. By transcriptome and m6A sequencing data conjointly, we discovered that JHA significantly regulated the m6A modification in the PSG of B. mori and many m6A-containing genes are related to nucleic acid binding, nucleus, and nucleobase-containing compound metabolism. Notably, 547 genes were significantly regulated by JHA at both the m6A modification and expression levels, especially 16 silk-associated genes, including sericin2, seroin1, Serine protease inhibitors 4 (BmSPI4), Serine protease inhibitors 5 (BmSPI5), and LIM domain-binding protein 2 (Ldb). Among them, 11 silk associated genes were significantly affected by METTL3 knockdown, validating that these genes are targets of m6A modification. Furthermore, we confirm that JHA directly regulates the expression of BmSPI4 and BmSPI5 through m6A modification of CDS regions. These results demonstrate the essential role of m6A methylation regulated by JH in PSG, and elucidate a novel mechanism by which JH affects silk gland development via m6A methylation. This study uncovers that m6A modification is a critical factor mediating the effect of JH in insects.

Psychosomatic mechanisms of heart failure symptoms on quality of life in patients with chronic heart failure: A multi-centre cross-sectional study.

AIMS: To determine the contributions of different kinds of symptoms to the quality of life and mediating effect of psychological and physical symptoms between heart failure symptoms and quality of life. DESIGN: A multi-centre cross-sectional study. METHODS: 2006 chronic heart failure patients from four cities were recruited in China from January 2021 to December 2022. Patients' symptoms and quality of life were self-reported, and data were analysed using correlation analysis, dominance analysis and mediating effects analysis. RESULTS: The dominance analysis revealed that the overall mean contributions of heart failure, psychological and physical symptoms were .083, .085 and .111; 29.5%, 30.2% and 39.5% of the known variance. And heart failure symptoms could negatively affect quality of life through psychological and physical symptoms, accounting for 28.39% and 22.95% of the total effect. Heart failure symptoms could also affect quality of life through the chain-mediated effect of physical and psychological symptoms, accounting for 16.74%. CONCLUSIONS: Physiological symptoms had the strongest effect on quality of life and heart failure symptoms had the weakest. Most of the effect for heart failure symptoms on quality of life in chronic heart failure patients was mediated by psychological and physiological symptoms. RELEVANCE TO CLINICAL PRACTICE: It is important to design non-pharmacological intervention plans for the enhancement of physical and psychological symptoms' management skills, to reduce the adverse impact of heart failure symptoms on quality of life. REPORTING METHOD: Study methods and results reported in adherence to the STROBE checklist. NO PATIENT OR PUBLIC CONTRIBUTION: No patients or members of the public were involved in the study.

High-resolution radar ranging based on the ultra-wideband chaotic optoelectronic oscillator.

A high-resolution radar ranging scheme is proposed and demonstrated based on the ultra-wideband chaotic optoelectronic oscillator (OEO). Through biasing the electro-optic intensity modulator near its minimum transmission point, high-dimensional chaotic signals with flat spectra and low time-delayed signatures can be generated in the OEO, which are favorable for increasing the ranging resolution and the confidentiality. In the experiment, the optimized broadband OEO generates a high-dimensional chaotic signal with a flat spectrum in the frequency range of 2 GHz to 16 GHz and a high permutation entropy of 0.9754. This chaotic signal is used to achieve multiple target ranging, where a ranging resolution of 1.4 cm is realized.

Neuromorphic regenerative memory optoelectronic oscillator.

Neuromorphic spiking information processing based on neuron-like excitable effect has achieved rapid development in recent years due to its advantages such as ultra-high operation speed, programming-free implementation and low power consumption. However, the current physical platforms lack building blocks like compilers, logic gates, and more importantly, data memory. These factors become the shackles to construct a full-physical layer neural network. In this paper, a neuromorphic regenerative memory scheme is proposed based on a time-delayed broadband nonlinear optoelectronic oscillator (OEO), which enables reshaping and regenerating on-off keying encoding sequences. Through biasing the dual-drive Mach-Zehnder electro-optic modulator in the OEO cavity near its minimum transmission point, the OEO can work in excitable regime, where localized states are maintained for robust nonlinear spiking response. Both simulation and experiment are carried out to demonstrate the proposed scheme, where the simulation results and the experimental results fit in with each other. The proposed OEO-based neuromorphic regenerative memory scheme exhibits long-term response ability for short-term excitation, which shows an enormous application potential for high-speed neuromorphic information buffering, optoelectronic interconnection and computing.

Instantaneous bandwidth expansion of photonic sampling analog-to-digital conversion for linear frequency modulation waveforms based on up-sampling and fractional Fourier transform signal processing.

An approach to expanding the instantaneous bandwidth of a photonic sampling analog-to-digital converter (ADC) for receiving linear frequency modulation waveforms (LFMWs) is proposed and experimentally demonstrated based on up-sampling and filtering in the fractional Fourier domain. Through twice zero interpolation, the equivalent sampling rate is quadrupled, which also quadruples the nominal instantaneous bandwidth of the photonic sampling ADC. In addition, with the assistance of bandpass filtering in the fraction Fourier domain, the image signals and the harmonic distortions generated in the interpolation process are filtered out. As a result, the effective instantaneous bandwidth of the photonic sampling ADC is doubled. In the experiment, the instantaneous bandwidth of a photonic sampling ADC with a sampling rate of 5 GSa/s for receiving LFMWs is increased from 2.5 GHz to 5 GHz by using the proposed method. Input LFMWs within the frequency range of 24-27 GHz and 30-33 GHz, i.e., with an instantaneous bandwidth of 3 GHz, are digitized without frequency-domain aliasing. Besides, the ability of the proposed method to enhance the ranging accuracy in a broadband radar system is demonstrated. This method reduces the hardware complexity of the photonic sampling ADC for receiving broadband LFMWs in radar systems.

Time-delay signature suppression of the chaotic signal in a semiconductor laser based on optoelectronic hybrid feedback.

An approach to generating chaotic signals with low time-delay signatures (TDSs) from a semiconductor laser (SCL) is proposed and demonstrated based on optoelectronic hybrid feedback. Through using a chirped fiber Bragg grating (CFBG) to provide distributed feedback, a chaotic signal with a low TDS is generated from the SCL. With the assistance of the nonlinear optoelectronic feedback provided by a microwave photonic link, the relaxation oscillation effect in the SCL is effectively suppressed, and the periodicity of the oscillation is greatly weakened. Hence, the TDS of the generated chaotic signal from the SCL is further suppressed, and the effective bandwidth is enlarged. Both simulation and experiment are carried out to verify the feasibility of the proposed scheme to suppress the TDS. In the experiment, a chaotic signal with a large effective bandwidth of 12.93 GHz, an extremely high permutation entropy (PE) of 0.9983, and a low TDS of 0.04, is generated by using a CFBG with a dispersion coefficient of 22.33 ps/nm. This TDS value is at the same level as that obtained by using the SCL-based scheme relying solely on distributed feedback in a CFBG with a dispersion coefficient of 2000 ps/nm.

Evolution of m6A-related genes in insects and the function of METTL3 in silkworm embryonic development.

N6-methyladenosine (m6A) plays a key role in many biological processes. However, the function and evolutionary relationship of m6A-related genes in insects remain largely unknown. Here we analysed the phylogeny of m6A-related genes among 207 insect species and found that m6A-related genes are evolutionarily conserved in insects. Subcellular localization experiments of m6A-related proteins in BmN cells confirmed that BmYTHDF3 was localized in the cytoplasm, BmMETTL3, BmMETTL14, and BmYTHDC were localized in the nucleus, and FL2D was localized to both the nucleus and cytoplasm. We examined the expression patterns of m6A-related genes during the embryonic development of Bombyx mori. To elucidate the function of BmMETTL3 during the embryonic stage, RNA sequencing was performed to measure changes in gene expression in silkworm eggs after BmMETTL3 knockdown, as well as in BmN cells overexpressing BmMETTL3. The global transcriptional pattern showed that knockdown of BmMETTL3 affected multiple cellular processes, including oxidoreductase activity, transcription regulator activity, and the cation binding. In addition, transcriptomic data revealed that many observed DEGs were associated with fundamental metabolic processes, including carbon metabolism, purine metabolism, amino acid biosynthesis, and the citrate cycle. Interestingly, we found that knockdown of BmMETTL3 significantly affected Wnt and Toll/Imd pathways in embryos. Taken together, these results suggest that BmMETTL3 plays an essential role in the embryonic development of B. mori, and deepen our understanding of the function of m6A-related genes in insects.

Pulse generation with programmable positions based on a phase-modulated optical frequency-shifting loop.

An approach to generating pulses with programmable positions is proposed and demonstrated based on a phase-modulated optical frequency-shifting loop (OFSL). By setting the OFSL to operate in the integer Talbot state, pulses are generated in the phase-locked positions, since the additional phase introduced by the electro-optic phase modulator (PM) in the OFSL is equal to an integer multiple of 2π in each round trip. Therefore, the pulse positions can be controlled and encoded by designing the driving waveform of the PM in a round-trip time. In the experiment, linear, round-trip, quadratic, and sinusoidal variations of pulse intervals are achieved by applying the corresponding driving waveforms to the PM. Pulse trains with coded pulse positions are also realized. In addition, the OFSL driven by waveforms with repetition rates equal to double and triple the free spectral range of the loop is also demonstrated. The proposed scheme paves a way to generate optical pulse trains with user-defined pulse positions, which can be used for such applications as compressed sensing and lidar.

Development of a personalized dendritic cell vaccine and single-cell RNA sequencing-guided assessment of its cell type composition.

BACKGROUND AIMS: Dendritic cell (DC)-based immunotherapy is a promising approach to treat cancer; however, there is no consensus on the manufacturing processes. Cell type heterogeneity in products manufactured by various methods is understudied and may elicit safety concerns from the regulatory perspective. METHODS: We characterized the cell type composition of a recently developed DC vaccine, CUD-002, consisting of DCs loaded with mRNA encoding personalized tumor neoantigens (NCT05270720). RESULTS: Using single-cell transcriptomic analysis as an unbiased approach, we found that >80% cells in the final product were DCs and the rest primarily comprised myelocytes and lymphocytes. Subsequent fluorescence-activated cell sorting analyses confirmed these cellular identities. These results indicate that unintended cells originate from leukapheresis, the first step of the manufacturing process, and thus likely safe. Consistently, no overt toxicity or tumorigenicity was observed in mice inoculated with CUD-002. CONCLUSIONS: Considering that leukapheresis is a widely used procedure for collecting diverse peripheral blood cell types to manufacture various cytotherapies, this study establishes a workflow to analyze and address regulatory considerations on cell type heterogeneity.

Divergent synthesis of bis(indolyl)methanes via FeIII-catalysed regioselective dehydrogenative coupling reactions: a biomimetic approach to 6,6'-bis-(debromo)-gelliusine F.

The divergent dehydrogenative coupling reactions of tryptamines with the catalysis of nontoxic FeIII salts in the presence of DDQ as the co-oxidant have been developed. Remarkably, the transformations feature a rapid and regioselective assembly of diverse 2,8'- and N1,8'-bis(indolyl) methane derivatives from readily-available starting materials by simply changing the FeIII salt and reaction temperature. Besides, the fast reaction rate, mild reaction conditions, low catalyst cost and easy operations make this methodology quite useful. The synthetic utility was further demonstrated in the biomimetic synthesis of 6,6'-bis-(debromo)-gelliusine F.

Imaginal disc growth factor is involved in melanin synthesis and energy metabolism in Bombyx mori.

The imaginal disc growth factor (IDGF), belonging to the glycoside hydrolase 18 family, plays an important role in various physiological processes in insects. However, the detail physiological function of IDGF is still unclear. In this study, transcriptome analysis was performed on the fatbody isolated from staged control and BmIDGF mutant silkworm larvae. Transcriptional profiling revealed that the absence of BmIDGF significantly affected differentially expressed genes involved in tyrosine and purine metabolism, as well as multiple energy metabolism pathways, including glycolysis, galactose, starch, and sucrose metabolism. The interruption of BmIDGF caused similar and specific gene expression changes to male and female fatbody. Furthermore, a genome-scale metabolic network integrating metabolomic and transcriptomic datasets revealed 11 pathways significantly altered at the transcriptional and metabolic levels, including amino acid, carbohydrate, uric acid metabolism pathways, insect hormone biosynthesis, and ABC transporters. In conclusion, this multiomics analysis suggests that IDGF is involved in gene-metabolism interactions, revealing its unique role in melanin synthesis and energy metabolism. This study provides new insights into the physiological function of IDGF in insects.

CAF-derived exosomes transmitted Gremlin-1 promotes cancer progression and decreases the sensitivity of hepatoma cells to sorafenib.

Hepatocellular carcinoma (HCC) is one of the most lethal malignancies worldwide because of metastasis. An increasing number of studies have reported that cancer-associated fibroblasts (CAFs) have emerged as the largest component of the stroma and play a critical role in tumor-promoting processes. However, the effects of CAFs on cancer progression and the sensitivity of hepatoma cells to sorafenib are not well characterized. Here, we identified the proteome of CAF-derived exosomes, and unveiled that exosomal Gremlin-1 derived from CAFs contributes to epithelial-mesenchymal transition (EMT) of hepatoma cells and the decrease of the sorafenib sensitivity through regulating Wnt/ß-catenin and BMP signaling pathways. Compared to control subjects, the level of plasma exosomal Gremlin-1 was significantly increased in HCC patients. Further studies indicated that plasma exosomal Gremlin-1 may predict sorafenib response in HCC patients. Collectively, our findings uncover CAFs-derived Gremlin-1-rich exosomes promote EMT and decrease the sensitivity of hepatoma cells to sorafenib by Wnt/ß-catenin and BMP signaling.

Urokinase-type plasminogen activator receptor (uPAR) as a therapeutic target in cancer.

Urokinase-type plasminogen activator receptor (uPAR) is an attractive target for the treatment of cancer, because it is expressed at low levels in healthy tissues but at high levels in malignant tumours. uPAR is closely related to the invasion and metastasis of malignant tumours, plays important roles in the degradation of extracellular matrix (ECM), tumour angiogenesis, cell proliferation and apoptosis, and is associated with the multidrug resistance (MDR) of tumour cells, which has important guiding significance for the judgement of tumor malignancy and prognosis. Several uPAR-targeted antitumour therapeutic agents have been developed to suppress tumour growth, metastatic processes and drug resistance. Here, we review the recent advances in the development of uPAR-targeted antitumor therapeutic strategies, including nanoplatforms carrying therapeutic agents, photodynamic therapy (PDT)/photothermal therapy (PTT) platforms, oncolytic virotherapy, gene therapy technologies, monoclonal antibody therapy and tumour immunotherapy, to promote the translation of these therapeutic agents to clinical applications.

GPS2 promotes erythroid differentiation by control of the stability of EKLF protein.

Erythropoiesis is a complex multistage process that involves differentiation of early erythroid progenitors to enucleated mature red blood cells, in which lineage-specific transcription factors play essential roles. Erythroid Krüppel-like factor (EKLF/KLF1) is a pleiotropic erythroid transcription factor that is required for the proper maturation of the erythroid cells, whose expression and activation are tightly controlled in a temporal and differentiation stage-specific manner. Here, we uncover a novel role of G-protein pathway suppressor 2 (GPS2), a subunit of the nuclear receptor corepressor/silencing mediator of retinoic acid and thyroid hormone receptor corepressor complex, in erythrocyte differentiation. Our study demonstrates that knockdown of GPS2 significantly suppresses erythroid differentiation of human CD34+ cells cultured in vitro and xenotransplanted in nonobese diabetic/severe combined immunodeficiency/interleukin-2 receptor γ-chain null mice. Moreover, global deletion of GPS2 in mice causes impaired erythropoiesis in the fetal liver and leads to severe anemia. Flow cytometric analysis and Wright-Giemsa staining show a defective differentiation at late stages of erythropoiesis in Gps2-/- embryos. Mechanistically, GPS2 interacts with EKLF and prevents proteasome-mediated degradation of EKLF, thereby increasing EKLF stability and transcriptional activity. Moreover, we identify the amino acids 191-230 region in EKLF protein, responsible for GPS2 binding, that is highly conserved in mammals and essential for EKLF protein stability. Collectively, our study uncovers a previously unknown role of GPS2 as a posttranslational regulator that enhances the stability of EKLF protein and thereby promotes erythroid differentiation.

Predicting the risk of axillary lymph node metastasis in early breast cancer patients based on ultrasonographic-clinicopathologic features and the use of nomograms: a prospective single-center observational study.

OBJECTIVES: The purpose of this study was to establish two preoperative nomograms to evaluate the risk for axillary lymph node (ALN) metastasis in early breast cancer patients based on ultrasonographic-clinicopathologic features. METHODS: We prospectively evaluated 593 consecutive female participants who were diagnosed with cT1-3N0-1M0 breast cancer between March 2018 and May 2019 at Sun Yat-Sen Memorial Hospital. The participants were randomly classified into training and validation sets in a 4:1 ratio for the development and validation of the nomograms, respectively. Multivariate logistic regression analysis was performed to identify independent predictors of ALN status. We developed Nomogram A and Nomogram B to predict ALN metastasis (presence vs. absence) and the number of metastatic ALNs (≤ 2 vs. > 2), respectively. RESULTS: A total of 528 participants were evaluated in the final analyses. Multivariable analysis revealed that the number of suspicious lymph nodes, long axis, short-to-long axis ratio, cortical thickness, tumor location, and histological grade were independent predictors of ALN status. The AUCs of nomogram A in the training and validation groups were 0.83 and 0.78, respectively. The AUCs of nomogram B in the training and validation groups were 0.87 and 0.87, respectively. Both nomograms were well-calibrated. CONCLUSION: We developed two preoperative nomograms that can be used to predict ALN metastasis (presence vs. absence) and the number of metastatic ALNs (≤ 2 vs. > 2) in early breast cancer patients. Both nomograms are useful tools that will help clinicians predict the risk of ALN metastasis and facilitate therapy decision-making about axillary surgery. KEY POINTS: • We developed two preoperative nomograms to predict axillary lymph node status based on ultrasonographic-clinicopathologic features. • Nomogram A was used to predict axillary lymph node metastasis (presence vs. absence). The AUCs in the training and validation groups were 0.83 and 0.78, respectively. Nomogram B was used to estimate the number of metastatic lymph nodes ( ≤ 2 vs. > 2). The AUCs in the training and validation group were 0.87 and 0.87, respectively. • Our nomograms may help clinicians weigh the risks and benefits of axillary surgery more appropriately.