Enhancing lobaplatin sensitivity in lung adenocarcinoma through inhibiting LDHA-targeted metabolic pathways.

Lung adenocarcinoma (LUAD), a subtype of non-small cell lung cancer (NSCLC), is associated with high incidence and mortality rates. Effective treatment options are limited due to the frequent development of multidrug resistance, making it crucial to identify new therapeutic targets and sensitizing agents. This study investigates the role of Lactate dehydrogenase A (LDHA) in enhancing the chemotherapy sensitivity of Lobaplatin (LBP) in LUAD. Bioinformatics analyses were performed using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) to assess LDHA expression in LUAD tissues. LUAD cell lines A549 and NCL-H1975 were treated with siRNA targeting LDHA and the small molecule inhibitor Oxamate. We measured changes in lactate production, ATP levels, NAD+ and pyruvate levels, and assessed cell viability. The chemotherapy sensitivity to Lobaplatin was evaluated, and key signaling pathways related to chemotherapy resistance were analyzed. The inhibition of LDHA resulted in a significant reduction in lactate production and ATP levels, along with an increase in NAD+ and pyruvate levels. These metabolic alterations led to decreased cell viability and enhanced sensitivity to Lobaplatin. The study identified the PI3K/AKT signaling pathway as a critical mediator of this enhanced sensitivity, with reduced phosphorylation of AKT observed upon LDHA inhibition. Furthermore, the combination of LDHA inhibition and Lobaplatin treatment demonstrated a synergistic effect, significantly inhibiting tumor growth and highlighting the potential of LDHA as a therapeutic target to overcome drug resistance in LUAD. Targeting LDHA and disrupting lactate metabolism and its signaling pathways can effectively enhance the sensitivity of LUAD to Lobaplatin, providing a promising approach to overcoming multidrug resistance. These findings offer valuable insights into developing new treatment strategies for lung adenocarcinoma, emphasizing the role of metabolic pathways in cancer therapy.

Yuan S ，Ou W ，Mi X ，Hou J ... -  《PLoS One》

[GINS1 Enhances Glycolysis, Proliferation and Metastasis in Lung Adenocarcinoma Cells by Activating the Notch/PI3K/AKT/mTORC1 Signaling Pathway].

Huo Y ，Xu X ，Ma X ，Feng Y ... -  《-》

RBIS regulates ribosome biogenesis to affect progression in lung adenocarcinoma.

Increased ribosome biogenesis is required for tumor growth. In this study, we investigated the function and underlying molecular mechanism of ribosome biogenesis factor (RBIS) in the progression of non-small cell lung cancer (NSCLC). In our study, we conducted a comprehensive analysis to identify key genes implicated in ribosome biogenesis by leveraging a Gene Set Enrichment Analysis (GSEA) dataset. Subsequently, we performed a comparative analysis of gene expression profiles by utilizing data from the Gene Expression Omnibus (GEO) datasets to ascertain differentially expressed genes (DEGs) between cancerous and adjacent non-cancerous tissues. Through the intersection of gene sets derived from GSEA and GEO, we identified a cohort of ribosome-associated genes that might exert a substantial influence on the progression of lung adenocarcinoma. Following an extensive literature review, we have identified the RBIS gene as an interesting candidate for further investigation. To elucidate the in vitro functional role of RBIS, several assays was employed, including the Transwell migration and invasion assay, wound healing assay, Cell Counting Kit-8 (CCK-8) proliferation assay, and colony formation assay. Subcutaneous and tail vein injection-based lung metastasis xenograft tumor models were used in evaluating the tumorigenic potential, growth, and metastatic spread of lung cancer cells. Flow cytometry analysis was employed to investigate cell cycle distribution and apoptotic rates. Additionally, real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was utilized to quantify the mRNA expression levels of genes. To comprehensively assess the translational efficiency of nascent proteins, we employed polysome profiling analysis to provide insights into the cellular translational landscape. Furthermore, we quantified global protein synthesis using a fluorescence-based assay to measure protein synthesis rates. The immunofluorescence technology was utilized to study the subcellular reorganization of the nucleolus. We conducted co-immunoprecipitation (Co-IP) assays followed by Western blot analysis to identify potential proteins interacted with RBIS. The half maximal inhibitory concentration (IC50) was used for evaluating the chemosensitivity of lung cancer cells to gemcitabine. Additionally, the colony formation assay was employed to assess the survival and proliferative capacity post-treatment of gemcitabine. The database analysis showed that RBIS was upregulated in lung adenocarcinoma, and its high expression was associated with poor prognosis; Knockdown of RBIS significantly inhibited NSCLC cell migration, invasion and proliferation in vitro and xenograft tumor growth and metastasis in vivo. Additionally, knockdown of RBIS led to G0/G1 phase arrest and significantly increased apoptosis in lung adenocarcinoma cells. Mechanistically, downregulation of RBIS significantly decreased the expression of 47S ribosomal RNA (rRNA), a component associated with ribosome assembly. Polysome profiling analysis indicated that RBIS knockdown affected protein translation efficiency, and global protein synthesis assay further verified that RBIS knockdown inhibited synthesis of newborn proteins. Additionally, the ribosomal biogenesis-targeting drugs CX-5461 and the loss of RBIS exhibited synergistic effects in inhibiting cell cycle progression and inducing apoptosis. Furthermore, the ribosomal maturation factor GNL2 was identified as the key downstream regulator of RBIS in ribosome biogenesis. Notably, knockdown of RBIS substantially increased the sensitivity of lung adenocarcinoma cells to the chemotherapeutic drug gemcitabine, highlighting its l role in chemotherapy. Collectively, these studies suggested the close involvement of RBIS in the progression of lung adenocarcinoma, providing new insights for targeted therapeutic interventions involving ribosomes.

Pan H ，Liao L ，Xu S ，Xu Y ，Chai W ，Liu X ，Li J ，Cao Y ，Sun L ，Liu Q ，Yan M ... -  《Journal of Translational Medicine》

Machine learning-based prognostic model of lactylation-related genes for predicting prognosis and immune infiltration in patients with lung adenocarcinoma.

Histone lactylation is a novel epigenetic modification that is involved in a variety of critical biological regulations. However, the role of lactylation-related genes in lung adenocarcinoma has yet to be investigated. RNA-seq data and clinical information of LUAD were downloaded from TCGA and GEO datasets. Unsupervised consistent cluster analysis was performed to identify differentially expressed genes (DEGs) between the two clusters, and risk prediction models were constructed by Cox regression analysis and LASSO analysis. Kaplan-Meier (KM) survival analysis, ROC curves and nomograms were used to validate the accuracy of the models. We also explored the differences in risk scores in terms of immune cell infiltration, immune cell function, TMB, TIDE, and anticancer drug sensitivity. In addition, single-cell clustering and trajectory analysis were performed to further understand the significance of lactylation-related genes. We further analyzed lactate content and glucose uptake in lung adenocarcinoma cells and tissues. Changes in LUAD cell function after knockdown of lactate dehydrogenase (LDHA) by CCK-8, colony formation and transwell assays. Finally, we analyzed the expression of KRT81 in LUAD tissues and cell lines using qRT-PCR, WB, and IHC. Changes in KRT81 function in LUAD cells were detected by CCK-8, colony formation, wound healing, transwell, and flow cytometry. A nude mouse xenograft model and a KrasLSL-G12D in situ lung adenocarcinoma mouse model were used to elucidate the role of KRT81 in LUAD. After identifying 26 lactylation-associated DEGs, we constructed 10 lactylation-associated lung adenocarcinoma prognostic models with prognostic value for LUAD patients. A high score indicates a poor prognosis. There were significant differences between the high-risk and low-risk groups in the phenotypes of immune cell infiltration rate, immune cell function, gene mutation frequency, and anticancer drug sensitivity. TMB and TIDE scores were higher in high-risk score patients than in low-risk score patients. MS4A1 was predominantly expressed in B-cell clusters and was identified to play a key role in B-cell differentiation. We further found that lactate content was abnormally elevated in lung adenocarcinoma cells and cancer tissues, and glucose uptake by lung adenocarcinoma cells was significantly increased. Down-regulation of LDHA inhibits tumor cell proliferation, migration and invasion. Finally, we verified that the model gene KRT81 is highly expressed in LUAD tissues and cell lines. Knockdown of KRT81 inhibited cell proliferation, migration, and invasion, leading to cell cycle arrest in the G0/G1 phase and increased apoptosis. KRT81 may play a tumorigenic role in LUAD through the EMT and PI3K/AKT pathways. In vivo, KRT81 knockdown inhibited tumor growth. We successfully constructed a new prognostic model for lactylation-related genes. Lactate content and glucose uptake are significantly higher in lung adenocarcinoma cells and cancer tissues. In addition, KRT81 was validated at cellular and animal levels as a possible new target for the treatment of LUAD, and this study provides a new perspective for the individualized treatment of LUAD.

Gao M ，Wang M ，Zhou S ，Hou J ，He W ，Shu Y ，Wang X ... -  《Cancer Cell International》

NGEF is a potential prognostic biomarker and could serve as an indicator for immunotherapy and chemotherapy in lung adenocarcinoma.

Neuronal guanine nucleotide exchange factor (NGEF) plays a key role in several cancers; however, its role in lung adenocarcinoma (LUAD) remains unclear. The aim of this study was to evaluate the efficacy of NGEF as a prognostic biomarker and potential therapeutic target for LUAD. NGEF expression data for multiple cancers and LUAD were downloaded from multiple databases. The high- and low-NGEF expression groups were constructed based on median NGEF expression in LUAD samples, and then performed Kaplan-Meier survival analysis. Differentially expressed genes (DEGs) from the two NGEF expression groups were screened and applied to construct a protein-protein interaction network. The primary pathways were obtained using gene set enrichment analysis. The associations between NGEF expression and clinical characteristics, immune infiltration, immune checkpoint inhibitors (ICIs), sensitivity to chemotherapy, and tumor mutation burden (TMB) were investigated using R. Levels of NGEF expression in the lung tissue was validated using single-cell RNA sequencing, quantitative polymerase chain reaction (qPCR), immunohistochemical staining, and western blot analysis. The expression of NGEF mRNA was upregulated in multiple cancers. mRNA and protein expression levels of NGEF were higher in patients with LUAD than in controls, as validated using qPCR and western blot. High NGEF expression was an independent prognostic factor for LUAD and was associated with advanced tumor stage, large tumor size, more lymph node metastasis, and worse overall survival (OS). A total of 182 overlapping DEGs were screened between The Cancer Genome Atlas and GSE31210, among which the top 20 hub genes were identified. NGEF expression was mainly enriched in the pathways of apoptosis, cell cycle, and DNA replication. Moreover, elevated NGEF expression were associated with a high fraction of activated memory CD4+ T cells and M0 macrophages; elevated expression levels of the ICIs: programmed cell death 1 and programmed cell death 1 ligand 1 expression; higher TMB; and better sensitivity to bortezomib, docetaxel, paclitaxel, and parthenolide, but less sensitivity to axitinib and metformin. NGEF expression is upregulated in LUAD and is significantly associated with tumor stages, OS probability, immune infiltration, immunotherapy response, and chemotherapy response. NGEF may be a potential diagnostic and prognostic biomarker and therapeutic target in LUAD.

Chen X ，Zhang T ，He YQ ，Miao TW ，Yin J ，Ding Q ，Yang M ，Chen FY ，Zeng HP ，Liu J ，Zhu Q ... -  《BMC Pulmonary Medicine》