Identification and validation of Golgi apparatus-related signature for predicting prognosis and immunotherapy response in breast cancer.

BACKGROUND: The Golgi apparatus plays a pivotal role in various aspects of cancer. This study aims to investigate the predictive value of Golgi apparatus-related genes (GARGs) in breast cancer prognosis and immunotherapy response evaluation. METHODS: Transcriptional and clinical data from the TCGA-BRCA cohort and GSE96058 cohort were utilized to construct and validate a prognostic model for breast cancer using Cox regression analysis. Differences in immune landscape, somatic mutations, gene expression, drug sensitivity, and immunotherapy response between different risk groups were assessed. A prognostic nomogram for breast cancer was further developed and evaluated. qPCR and single-cell sequencing analyses were performed to validate the expression of GARGs. RESULTS: A total of 394 GARGs significantly associated with breast cancer prognosis were identified, leading to the construction of a prognostic risk feature comprising 10 GARGs. This feature effectively stratified breast cancer patients into high-risk and low-risk groups, with the high-risk group exhibiting significantly worse prognosis. Meanwhile, significant differences in clinicopathological features, immune infiltration, drug sensitivity, and immunotherapy response were observed between the high- and low-risk groups. The constructed nomogram incorporating these factors showed superior performance in prognostic assessment for breast cancer patients. Ultimately, the utilization of qPCR and single-cell sequencing techniques substantiated the disparate expression patterns of these prognostic genes in breast cancer. CONCLUSION: Our findings demonstrate that a prognostic risk feature derived from GARGs holds promising application potential for predicting prognosis and evaluating immunotherapy response in breast cancer patients.

TBOPP, a DOCK1 Inhibitor, Potentiates Cisplatin Efficacy in Breast Cancer by Regulating Twist-mediated EMT.

BACKGROUND: DOCK1 has been reported to be involved in tumor progression and resistance. 1-(2-(30-(trifluoromethyl)-[1,10-biphenyl]-4-yl)-2-oxoethyl)-5-pyrrolidinylsulfonyl2(1H)- pyridone (TBOPP) is a selective DOCK1 inhibitor; however, the role and molecular mechanisms of DOCK1 and its inhibition in breast cancer (BC) resistance remain poorly understood. OBJECTIVE: This study aims toinvestigate the underlying mechanisms of DOCK1 in BC resistance. METHODS: DOCK1 or Twist siRNA and Twist plasmid were used to explore the function of DOCK1 in vitro experiments. A mouse xenograft model was used for in vivo experiments. RESULTS: In the present study, we demonstrated that DOCK1 siRNA promoted cisplatin sensitivity in BC cells. Moreover, TBOPP also enhances the therapeutic effect of cisplatin both in vitro and in vivo. Mechanistically, DOCK1 siRNA inhibited EMT. Twist 1 is one of the EMT-inducing transcription factors and is known to induce EMT. To further reveal the effect of DOCK in BC cells, we co-transfected with DOCK1 and Twist1 siRNA to BC cells and found that co-transfection with DOCK1 and Twist siRNA could not further enhance the cisplatin sensitivity of BC cells. Moreover, DOCK1 siRNA failed to reverse the effect of Twist 1 up-regulation. CONCLUSION: Taken together, these results demonstrate that DOCK1 may function as a potential therapeutic target in BC and that combining cisplatin with TBOPP may provide a promising therapeutic strategy for cisplatin-resistant BC patients.

Downregulation of long non-coding RNA MR4435-2HG suppresses breast cancer progression via the Wnt/ß-catenin signaling pathway.

Extensive research has contributed to the current understanding of the critical roles played by long non-coding RNAs in various types of cancer. The present study aimed to investigate the function and mechanism of the long non-coding RNA, MIR4435-2HG (also termed LINC00978), in breast cancer growth and metastasis. Using Gene Expression Profiling Interactive Analysis, an online web tool, it was revealed that MIR4435-2HG was upregulated in breast cancer tissue, and its high expression was associated with poor prognosis based on The Cancer Genome Atlas database. MIR4435-2HG knockdown increased cell apoptosis but decreased cell proliferation, migration and invasion. MIR4435-2HG knockdown increased pro-apoptotic protein expression but decreased anti-apoptotic protein expression. In addition, MIR4435-2HG knockdown leads to dysregulation of epithelial-to-mesenchymal transition-associated genes. Furthermore, knockdown of MIR4435-2HG results in inactivation of the Wnt/ß-catenin signaling pathway. The results of the present study demonstrate the tumor-promoting role of MIR4435-2HG in breast cancer progression.