Bladder cancer is the most prevalent tumor of the urinary system, characterized by a high recurrence rate. The incidence and mortality rates of bladder cancer have been steadily increasing, in line with the accelerated aging of the global population[32]. cells respond to increased replication stress by activating pathways that are responsible for inhibiting and repairing replication stress. This study has identified a set of key core genes that play a crucial role in the pathogenesis of BLCA by integrating differentially expressed genes in BLCA and DNA replication stress genes (DRSGs). Subsequent enrichment analysis has revealed the biological processes regulated by these genes, highlighting their significant role in driving the progression of BLCA. The genes analyzed in this study were BUB1B, RAD9A, MCM2, NFIA, TUBA1A, CHMP4C, CLSPN, TUBB2B and VCL. Among these genes, the first four were found to be associated with the cell cycle while the last five were related to mitosis. These genetic factors have been shown to impact the normal transport and secretion of substances within cells. It is possible that these findings may have implications for certain diseases or cellular physiological disorders.
BUB1B, a crucial mitotic checkpoint protein, plays a key role as part of the mitotic spindle checkpoint complex. The BUB1B gene is frequently found to be upregulated in various types of cancer[33]. In this study, by qRT-PCR assay, the results showed that the expression level of BUB1B in BCa cell line 5637 was higher than that in normal uroepithelial cell line SV-HUC-1. Additionally, NFIA plays a important role as a transcriptional regulator in the genetic program of brown fat[34]. Additionally, NFIA has emerged as a key regulator in cancer development[35]. MiR-212-3p has been demonstrated to suppress the proliferation of BLCA cells and promote cell apoptosis by directly targeting NFIA in previous studies[36]. The MCM protein is believed to be closely associated with tumor development[37]. The expression of MCM2 protein has been found to hold prognostic significance in prostate cancer[35], non-small cell lung cancer[38], and oligodendroglioma[39]. Previous research has found a correlation between MCM2 expression and prognosis in BLCA[40]. Studies have indicated that RAD9A serves as a prognostic gene for telomere maintenance in BLCA, and it is found to be highly expressed in patients with BLCA[41]. Zhang P B et al.'s study revealed that TUBA1A has been identified as a potential target for multi-drug treatment of high-risk MIBC[42]. The immunohistochemical analysis by Gao M et al. revealed that CHMP4C was significantly elevated in BLCA tissues. Poor prognosis in BLCA patients was closely linked to this upregulation[43]. Studies have demonstrated that CLSPN is associated with DNA replication stress and serves as a key factor in driving cisplatin resistance in BLCA cells[44, 45]. TUBB2B and VCL have been relatively understudied in the context of BLCA. An improved prognosis may be achieved by identifying effective biomarkers for early diagnosis and timely intervention in BLCA.
Prognostic models are important for strategies for the treatment of bladder cancer. It developed using LASSO regression emphasize the potential use of genetic signatures in predicting patient outcomes, offering valuable clinical implications for risk assessment[16]. The LASSO algorithm was used to screen 9 genes and use them as biomarkers to establish a risk model in this study. This model was used to divide the participants into high-risk and low-risk groups. The survival analysis results showed that there were significant differences in outcomes between these two risk groups. BLCA is a tumor that is sensitive to the immune system and is infiltrated by various types of immune cells, such as T cells, macrophages, dendritic cells, neutrophils, and mast cells[46–48]. BLCA exhibits high heterogeneity in genetics, expression, and histology[49]. Therefore, achieving a precise comprehension of this heterogeneity could simplify the process of molecularly classifying BLCA and implementing personalized medicine. The prognosis of BLCA is closely linked to the presence of tumor-infiltrating immune cells. The recurrence prognosis of BLCA is significantly correlated with six types of immune infiltrating cells as demonstrated by previous studies[50]. The human bladder already has certain key immune cell populations that can recruit additional immune cells from circulation[51]. In this study, gene data from BLCA patients were collected from the TCGA database. Significant differences in 12 immune cell types were observed between the two risk groups in BLCA according to the results.
Additionally, Immune checkpoints are also an effective treatment. Immune checkpoint inhibitors (ICI) are pharmaceuticals that block immune checkpoints. The development of ICI has shown potential in improving the long-term survival rates of patients with various types of cancer, including bladder cancer and renal cell carcinoma[51]. Endogenous control mechanisms, such as immune checkpoints and immunosuppressive cells, are employed to attenuate the anti-tumor immune response during tumorigenesis[52]. ICI have demonstrated significant potential in the treatment of bladder cancer. Therefore, the current study conducted an analysis of the expression of 48 immune checkpoints in different risk groups. The results reveal significant variations in 18 immune checkpoints among the two risk groups. immune checkpoint proteins are vital in the management of inflammatory responses and cancer immunotherapy. Therefore, by identifying differentially expressed immune checkpoint proteins, it is anticipated that regulating the immune response through targeting these proteins could enhance immunotherapy for bladder cancer.
Despite the importance of DNA replication stress in the development of BLCA, the mode and mechanism of action are not well understood. We screened 9 biomarkers connected to DNA replication stress using bioinformatics methods based on data from TCGA and GEO public databases. The risk model constructed based on this screening provides a theoretical framework for exploring the molecular mechanism of BLCA. Multiple new therapies targeting DNA replication stress are currently under development, and these novel molecules and biomarkers have the potential to significantly advance the field and positively impact the treatment of cancer. While our study utilized statistical methods to screen and identify nine genes that may be associated with BLCA progression and prognosis, it is significant to note that large queue validation was lacking. Therefore, further molecular experiments on the 9 prognostic genes are necessary to confirm their association with BLCA. By identifying biomarkers linked to DNA replication stress, our study can aid in identifying prognostic risk stratification for bladder cancer and guide treatment decisions.