Biomedical subjects

Yu Lei

Publications and source records attributed to Yu Lei.

2 recordsLinked to original sources

PubMed2026

Overexpression of the tomato SlLEA_2-26 gene enhances the tolerance to drought and salt stresses in Arabidopsis thaliana.

Late embryogenesis abundant (LEA) proteins are pivotal in conferring cellular tolerance to abiotic stresses and sustaining plant growth and development. However, systematic functional characterization of the tomato SlLEA_2 gene family remains limited. To elucidate the role of tomato SlLEA_2-26 in abiotic stress responses, this study cloned its full-length cDNA. Quantitative real-time PCR (qRT-PCR) analysis revealed that SlLEA_2-26 exhibits predominant expression in flowers and fruits, and is strongly induced by drought, salt, Cu2+, and Pb2+ stresses. Three homozygous Arabidopsis thaliana T3 SlLEA_2-26-overexpression lines were generated and confirmed via genomic PCR. Under drought and salt stress, T3 A. thaliana lines overexpressing SlLEA_2-26 exhibited significantly enhanced seed germination rates, root elongation, and fresh weights compared to wild type (WT) plants, indicating improved stress tolerance during early seedling development. Furthermore, transgenic plants accumulated higher levels of soluble sugar and proline, and displayed elevated antioxidant enzyme activity compared to the WT, whereas contents of malondialdehyde (MDA) and reactive oxygen species (ROS) were markedly reduced relative to WT. qRT-PCR analysis confirmed the significant upregulation of SlLEA_2-26 in transgenic lines under drought and salt stress conditions, accompanied by elevated expression of AtP5CS1, AtCSD1, AtRD29A, AtRD26, and AtNCED3. Collectively, these results demonstrate that SlLEA_2-26 overexpression enhances drought and salt stress tolerance in A. thaliana by promoting the accumulation of osmoregulatory substances, augmenting antioxidant defense capacity, and activating stress-responsive gene expression. This study provides a theoretical foundation and valuable genetic resources for breeding stress-tolerant tomatoes and other crops.

SlLEA_2–26↗

PubMed2025

Molecular features influencing clinical outcome of advanced HER2-positive gastric cancer receiving trastuzumab plus chemotherapy.

BACKGROUND: Less than half of the human epidermal growth factor receptor 2 (HER2)-positive gastric cancer (GC) patients respond to trastuzumab plus chemotherapy, and the outcomes are unsatisfactory. Understanding the underlying mechanisms remains crucial for identifying patients who are more likely to benefit from treatment. PATIENTS AND METHODS: We performed targeted DNA sequencing on paired pre-treatment and progressive tumour tissues from 22 HER2-positive advanced GC patients undergoing first-line treatment with trastuzumab and chemotherapy. Clinicopathological and genomic characteristics were assessed for the correlation with clinical outcomes. RESULTS: A performance status (PS) of 0-1 was associated with improved progression-free survival (PFS) and overall survival (OS) than a PS of 2. Poorly differentiated tumours exhibited shorter PFS than moderate or moderate-poor ones. Pre-treatment amplification of MYC or TOP2A gene was association with increased PFS, and suggested a potential benefit for OS. Patients with higher tumour mutation burden (TMB) experienced significantly worse PFS, while higher chromosome instability (CIN) appeared to be correlated with longer PFS. Compared to non-responders, responders had a higher CIN but similar TMB and intratumoural heterogeneity (ITH). PS and MYC amplification emerged as independent factors related to PFS according to multivariate survival analysis. Additionally, after treatment, TMB significantly increased in non-responders, while CIN significantly decreased in responders. CONCLUSIONS: Pre-treatment MYC amplification and PS were independently associated with clinical outcomes in HER2-positive advanced GC patients treated with first-line trastuzumab plus chemotherapy. Dynamic post-treatment changes in TMB and CIS provide valuable insights into the relationship between therapeutic response and distinct evolutionary trajectories.

Humans↗