Project description:Breast cancer (BC) stands as a predominant global malignancy, significantly contributing to female mortality. Recently uncovered, histone lysine lactylation (kla) has assumed a crucial role in cancer progression. However, the correlation with lncRNAs remains ambiguous. Scrutinizing lncRNAs associated with Kla not only improves clinical breast cancer management but also establishes a groundwork for antitumor drug development. We procured breast tissue samples, encompassing both normal and cancerous specimens, from The Cancer Genome Atlas (TCGA) database. Utilizing Cox regression and XGBoost methods, we developed a prognostic model using identified kla-related lncRNAs. The model's predictive efficacy underwent validation across training, testing, and the overall cohort. Functional analysis concerning kla-related lncRNAs ensued. We identified and screened 8 kla-related lncRNAs to formulate the risk model. Pathway analysis disclosed the connection between immune-related pathways and the risk model of kla-related lncRNAs. Significantly, the risk scores exhibited a correlation with both immune cell infiltration and immune function, indicating a clear association. Noteworthy is the observation that patients with elevated risk scores demonstrated an increased tumor mutation burden (TMB) and decreased tumor immune dysfunction and exclusion (TIDE) scores, suggesting heightened responses to immune checkpoint blockade. Our study uncovers a potential link between Kla-related lncRNAs and BC, providing innovative therapeutic guidelines for BC management.
Project description:Background Posttranslational modifications of histone lysine (K) have integral connections with cell metabolism, and participate in the carcinogenesis of various cancers. This study focuses on evaluating the expression of histone H4 lys 5 lactylation (H4K5lac) and its clinical role in breast cancer (BC). Methods During this research, immunohistochemistry (IHC) and immunoblotting, utilizing a specific primary anti-L-lactyl-histone H4 (Lys 5) rabbit monoclonal antibody, were employed to assess H4K5lac expression in BC tissue chips. H4K5lac expression in the peripheral blood mononuclear cells (PBMCs) of BC patients was investigated through immunoblotting. Results IHC revealed upregulation of histone H4K5lac in both triple-negative breast cancer (TNBC) and non-TNBC tissues, with positive rate of 91.40% [170/(150 + 19 + 17)] and 93.64% (103/110) in TNBC and non-TNBC tissues, respectively. The expression of H4K5lac demonstrated positive correlations with lymph nodes (%), and Ki-67 expression. Survival analysis indicated a negative correlation between H4K5lac expression and overall survival (OS) time in both TNBC (HR [hazard ratio] = 2.773, 95%CI [confidence interval]: 1.128-6.851, P = 0.0384) and non-TNBC cases (HR = 2.156, 95%CI: 1.011-4.599, P = 0.0275). Furthermore, elevated levels of H4K5lac were observed in the PBMCs of BC cases, and H4K5lac expression is positively correlated with serum lactate and carcinoma embryonic antigen (CEA) levels. Conclusions Histone H4K5lac exhibits increased levels in both BC tissues and PBMCs, suggesting its potential as a promising biomarker for BC. This study might pave the way toward novel lactylation treatment strategies in BC.
Project description:Mutations in genes encoding proteins involved in RNA splicing have been found to occur at relatively high frequencies in several tumour types including myelodysplastic syndromes, chronic lymphocytic leukaemia, uveal melanoma, and pancreatic cancer, and at lower frequencies in breast cancer. To investigate whether dysfunction in RNA splicing is implicated in the pathogenesis of breast cancer, we performed a re-analysis of published exome and whole genome sequencing data. This analysis revealed that mutations in spliceosomal component genes occurred in 5.6% of unselected breast cancers, including hotspot mutations in the SF3B1 gene, which were found in 1.8% of unselected breast cancers. SF3B1 mutations were significantly associated with ER-positive disease, AKT1 mutations, and distinct copy number alterations. Additional profiling of hotspot mutations in a panel of special histological subtypes of breast cancer showed that 16% and 6% of papillary and mucinous carcinomas of the breast harboured the SF3B1 K700E mutation. RNA sequencing identified differentially spliced events expressed in tumours with SF3B1 mutations including the protein coding genes TMEM14C, RPL31, DYNL11, UQCC, and ABCC5, and the long non-coding RNA CRNDE. Moreover, SF3B1 mutant cell lines were found to be sensitive to the SF3b complex inhibitor spliceostatin A and treatment resulted in perturbation of the splicing signature. Albeit rare, SF3B1 mutations result in alternative splicing events, and may constitute drivers and a novel therapeutic target in a subset of breast cancers.
Project description:Breast cancer is one of the most frequent cancer types worldwide and the first cause of cancer-related deaths in women. Although significant therapeutic advances have been achieved with drugs such as tamoxifen and trastuzumab, breast cancer still caused 627,000 deaths in 2018. Since cancer is a multifactorial disease, it has become necessary to develop new molecular therapies that can target several relevant cellular processes at once. Ion channels are versatile regulators of several physiological- and pathophysiological-related mechanisms, including cancer-relevant processes such as tumor progression, apoptosis inhibition, proliferation, migration, invasion, and chemoresistance. Ion channels are the main regulators of cellular functions, conducting ions selectively through a pore-forming structure located in the plasma membrane, protein-protein interactions one of their main regulatory mechanisms. Among the different ion channel families, the Transient Receptor Potential (TRP) family stands out in the context of breast cancer since several members have been proposed as prognostic markers in this pathology. However, only a few approaches exist to block their specific activity during tumoral progress. In this article, we describe several TRP channels that have been involved in breast cancer progress with a particular focus on their binding partners that have also been described as drivers of breast cancer progression. Here, we propose disrupting these interactions as attractive and potential new therapeutic targets for treating this neoplastic disease.
Project description:As a novel lactate-derived post-translational modification (PTM), lysine lactylation (Kla) is involved in diverse biological processes, and participates in human tumorigenesis. Identification of Kla substrates with their exact sites is crucial for revealing the molecular mechanisms of lactylation. In contrast with labor-intensive and time-consuming experimental approaches, computational prediction of Kla could provide convenience and increased speed, but is still lacking. In this work, although current identified Kla sites are limited, we constructed the first Kla benchmark dataset and developed a few-shot learning-based architecture approach to leverage the power of small datasets and reduce the impact of imbalance and overfitting. A maximum 11.7% (0.745 versus 0.667) increase of area under the curve (AUC) value was achieved in contrast to conventional machine learning methods. We conducted a comprehensive survey of the performance by combining 8 sequence-based features and 3 structure-based features and tailored a multi-feature hybrid system for synergistic combination. This system achieved >16.2% improvement of the AUC value (0.889 versus 0.765) compared with single feature-based models for the prediction of Kla sites in silico. Taken few-shot learning and hybrid system together, we present our newly designed predictor named FSL-Kla, which is not only a cutting-edge tool for Kla site profile but also could generate candidates for further experimental approaches. The webserver of FSL-Kla is freely accessible for academic research at http://kla.zbiolab.cn/.
Project description:Lysine L-lactylation (Kl-la) is a novel protein posttranslational modification (PTM) driven by L-lactate. This PTM has three isomers: Kl-la, N-ε-(carboxyethyl)-lysine (Kce) and D-lactyl-lysine (Kd-la), which are often confused in the context of the Warburg effect and nuclear presence. Here we introduce two methods to differentiate these isomers: a chemical derivatization and high-performance liquid chromatography analysis for efficient separation, and isomer-specific antibodies for high-selectivity identification. We demonstrated that Kl-la is the primary lactylation isomer on histones and dynamically regulated by glycolysis, not Kd-la or Kce, which are observed when the glyoxalase system was incomplete. The study also reveals that lactyl-coenzyme A, a precursor in L-lactylation, correlates positively with Kl-la levels. This work not only provides a methodology for distinguishing other PTM isomers, but also highlights Kl-la as the primary responder to glycolysis and the Warburg effect.
Project description:Triple-negative breast cancer (TNBC) presents the poorest prognosis among the breast cancer subtypes and no current standard therapy. Here, we performed an in-depth molecular analysis of a mouse model that establishes spontaneous lung metastasis from JygMC(A) cells. These primary tumors resembled the triple-negative breast cancer (TNBC) both phenotypically and molecularly. Morphologically, primary tumors presented both epithelial and spindle-like cells but displayed only adenocarcinoma-like features in lung parenchyma. The use of laser-capture microdissection combined with Nanostring mRNA and microRNA analysis revealed overexpression of either epithelial and miRNA-200 family or mesenchymal markers in adenocarcinoma and mesenchymal regions, respectively. Cripto-1, an embryonic stem cell marker, was present in spindle-like areas and its promoter showed activity in primary tumors. Cripto-1 knockout by the CRISPR-Cas9 system inhibited tumor growth and pulmonary metastasis. Our findings show characterization of a novel mouse model that mimics the TNBC and reveal Cripto-1 as a TNBC target hence may offer alternative treatment strategies for TNBC.
Project description:Transient receptor potential vanilloid type-2 (TRPV2) is an ion channel that is triggered by agonists like cannabidiol (CBD). Triple negative breast cancer (TNBC) is an aggressive disease with limited therapeutic options. Chemotherapy is still the first line for the treatment of TNBC patients; however, TNBC usually gains rapid resistance and unresponsiveness to chemotherapeutic drugs. In this study, we found that TRPV2 protein is highly up-regulated in TNBC tissues compared to normal breast tissues. We also observed that TNBC and estrogen receptor alpha negative (ERβ-) patients with higher TRPV2 expression have significantly higher recurrence free survival compared to patients with lower TRPV2 expression especially those who were treated with chemotherapy. In addition, we showed that TRPV2 overexpression or activation by CBD significantly increased doxorubicin (DOX) uptake and apoptosis in TNBC cells. The induction of DOX uptake was abrogated by TRPV2 blocking or downregulation. In vivo mouse model studies showed that the TNBC tumors derived from CBD+DOX treated mice have significantly reduced weight and increased apoptosis compared to those treated with CBD or DOX alone. Overall, our studies for the first time revealed that TRPV2 might be a good prognostic marker for TNBC and ERβ- breast cancer patient especially for those who are treated with chemotherapy. In addition, TRPV2 activation could be a novel therapeutic strategy to enhance the uptake and efficacy of chemotherapy in TNBC patients.
Project description:ObjectiveMicrotubule actin cross-linking factor 1 (MACF1) mutations are known to play an important role in the progression of various cancers. However, its role in breast cancer remains to be determined. In this study, we investigated how MACF1 mutations may play a role in breast cancer development.MethodsThe gene-expression profile data of patients with breast cancer were obtained from The Cancer Genome Atlas (TCGA)-Breast cancer cohort. We estimated the influence of MACF1 mutations on patient clinical prognosis using the Kaplan-Meier method. Further, patients with MACF1-mutant (MACF1-MT) and MACF1-wild-type (MACF1-WT) were compared to identify the differentially expressed genes (DEGs). We also performed functional enrichment analyses, constructed protein-protein interaction (PPI) and competing endogenous RNA (ceRNA) networks, and investigated the correlation between MACF1 mutations and immune-cell infiltration. To explore the prognostic value of MACF1 mutations, a nomogram was developed based on MACF1 mutations and other clinicopathological parameters.ResultsPatients with MACF1-MT had a worse prognosis and higher tumor mutation burden score (P < 0.05) than patients with MACF1-WT. MACF1 mutations were demonstrated to upregulate the mTOR signaling pathway and alter energy metabolism and tumor immune microenvironment. Thus, MACF1 mutations might affect immunogenicity and result in a lower response to immunotherapy. By analyzing the Genomics of Drug Sensitivity in Cancer (GDSC), the sensitivity of breast cancer cells to 13 drugs was found to be significantly enhanced by MACF1 mutations. The prognostic model was verified in predicting the outcome of breast cancer patients.ConclusionMACF1 mutations might be a potential prognostic biomarker and a therapeutic target for breast cancer.