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Lijun Shen

Publications and source records attributed to Lijun Shen.

2 recordsLinked to original sources

Integrating clinical and genomic features to predict response to neoadjuvant therapy in microsatellite-stable rectal cancer.

BACKGROUND: Neoadjuvant therapy (NAT) has shifted rectal cancer management toward organ preservation. However, achieving a complete response (CR) for "watch-and-wait" strategies is hindered by high response heterogeneity. Although immunotherapy-combined NAT has expanded the candidate pools, the predictive significance of molecular alterations remains unclear. OBJECTIVES: This study aimed to evaluate clinical and genomic profiles of rectal cancer patients undergoing NAT to identify response predictors and to develop a nomogram for estimating CR probability. DESIGN: Retrospective, single-center cohort study. METHODS: This study included 437 patients with rectal adenocarcinoma at Fudan University Shanghai Cancer Center between December 2019 and March 2023. Patients underwent paired tumor and germline genomic sequencing (887-gene panel) before NAT. Logistic and Cox regression analyses were performed to identify clinical and genetic risk factors associated with tumor response and long-term survival. RESULTS: Of the 437 patients, 96.6% had microsatellite-stable (MSS) tumors. In the MSS locally advanced rectal cancer cohort (N = 307), the CR rate was 35.5%. Multivariate analysis identified immunotherapy-combined NAT (iTNT) (OR 4.41, 95% CI: 2.42-8.27), SYNE1 mutation (OR 2.12, 95% CI: 1.06-4.26), negative mesorectal fascia (MRF) status (OR 0.34, 95% CI: 0.17-0.66), and lower tumor location (OR 0.48, 95% CI: 0.27-0.84) as independent predictors of CR. KRAS mutation was the sole independent predictor of reduced disease-free survival (DFS; HR 1.93, 95% CI: (1.11-3.36), p = 0.020). KRAS G12D subtype was associated with the worst 2-year distant metastasis-free survival (71.3%) and exhibited a distinct predilection for lung metastasis. The clinical-genomic nomogram yielded strong discrimination (AUC = 0.705) and calibration, with favorable DCA net benefit. CONCLUSION: Clinical and genomic features jointly determine outcomes in MSS rectal cancer. SYNE1 mutation serves as a novel biomarker for CR, while KRAS mutations, especially the G12D subtype, identify patients at high risk for systemic relapse. The clinical-genomic nomogram facilitates individualized selection for organ-preservation strategies.

biomarker

Semaglutide treatment in MOSH is associated with altered DNA methylation patterns of genes related to glycolipid metabolism.

Male obesity-associated secondary hypogonadism(MOSH) is a common disease among severely obese male patients. Although surgical interventions have demonstrated clinical benefits, a subset of patients continue to experience MOSH following surgery. Therefore, this study aims to investigate epigenetic changes associated with the use of the weight-loss drug Semaglutide in MOSH, focusing on DNA methylation and miRNA expression. In this exploratory study, samples were classified into three groups: a control group (n = 2), a MOSH group (n = 7), and a follow-up group (n = 4). DNA methylation analysis was performed on all samples, while miRNA sequencing was conducted on a subset of the samples: 2 from the control group, 7 from the MOSH group, and 2 from the follow-up group. Differentially expressed miRNAs (DEMs) were analyzed through the R package "limma", and the methylation level of CpG sites was analyzed based on the methylation β value, obtaining differentially methylated genes (DMGs). The functional enrichment analysis of miRNA target genes and methylation change genes was conducted using the R package "clusterProfiler". Finally, the regulatory networks of miRNA and methylation genes as well as the protein-protein interaction (PPI) network were analyzed. A total of 6 DEMs were screened out. The target genes of these DEMs were mainly enriched in pathways such as ATP binding, phosphorylation, cell adhesion, and Glycosphingolipid biosynthesis. Eighty DMGs were identified, and the largest number of DMGs were found in the X chromosome. In the regulatory network of DMGs and DEMs, hsa-miR-423-5p regulates most of these DMGs. Moreover, the PPI network shows that DPP6, DPP10, CACNA1C, and CNTNAP2 are the proteins with the strongest connectivity. Notably, differential CpG methylation changes were observed on chromosome 7, indicating a potential region of epigenetic alteration in MOSH; however, the biological and functional relevance of these changes remains unclear. Collectively, these findings suggest that Semaglutide treatment in MOSH may be associated with concurrent alterations in DNA methylation and miRNA expression, implicating genes related to energy and glycolipid metabolism, including DPP6, DPP10, CACNA1C, and CNTNAP2. These results are exploratory and hypothesis-generating, providing preliminary observations to inform future validation studies.

Semaglutide