Prevention and Treatment of Side Effects of Immunotherapy for Bladder Cancer

Overexpressed KCNK1 regulates potassium channels affecting molecular mechanisms and biological pathways in bladder cancer

BACKGROUND

This study aimed to explore the expression, molecular mechanism and its biological function of potassium two pore domain channel subfamily K member 1 (KCNK1) in bladder cancer (BC).

METHODS

We integrated large numbers of external samples (n = 1486) to assess KCNK1 mRNA expression levels and collected in-house samples (n = 245) for immunohistochemistry (IHC) experiments to validate at the KCNK1 protein level. Single-cell RNA sequencing (scRNA-seq) analysis was performed to further assess KCNK1 expression and cellular communication. The transcriptional regulatory mechanisms of KCNK1 expression were explored by ChIP-seq, ATAC-seq and ChIA-PET data. Highly expressed co-expressed genes (HECEGs) of KCNK1 were used to explore potential signalling pathways. Furthermore, the immunoassay, clinical significance and molecular docking of KCNK1 were calculated.

RESULTS

KCNK1 mRNA was significantly overexpressed in BC (SMD = 0.58, 95% CI [0.05; 1.11]), validated at the protein level (p < 0.0001). Upregulated KCNK1 mRNA exhibited highly distinguishing ability between BC and control samples (AUC = 0.82 [0.78-0.85]). Further, scRNA-seq analysis revealed that KCNK1 expression was predominantly clustered in BC epithelial cells and tended to increase with cellular differentiation. BC epithelial cells were involved in cellular communication mainly through the MK signalling pathway. Secondly, the KCNK1 transcription start site (TSS) showed promoter-enhancer interactions in three-dimensional space, while being transcriptionally regulated by GRHL2 and FOXA1. Most of the KCNK1 HECEGs were enriched in cell cycle-related signalling pathways. KCNK1 was mainly involved in cellular metabolism-related pathways and regulated cell membrane potassium channel activity. KCNK1 expression was associated with the level of infiltration of various immune cells. Immunotherapy and chemotherapy (docetaxel, paclitaxel and vinblastine) were more effective in BC patients in the high KCNK1 expression group. KCNK1 expression correlated with age, pathology grade and pathologic_M in BC patients.

CONCLUSIONS

KCNK1 was significantly overexpressed in BC. A complex and sophisticated three-dimensional spatial transcriptional regulatory network existed in the KCNK1 TSS and promoted the upregulated of KCNK1 expression. The high expression of KCNK1 might be involved in the cell cycle, cellular metabolism, and tumour microenvironment through the regulation of potassium channels, and ultimately contributed to the deterioration of BC.

A novel LINC02321 promotes cell proliferation and decreases cisplatin sensitivity in bladder cancer by regulating RUVBL2

Bladder cancer (BC) has a high incidence and is prone to recurrence. In most instances, the low 5-year survival rate of advanced BC patients results from postoperative recurrence and drug resistance. Long noncoding RNAs (lncRNAs) can participate in numerous biological functions by regulating the expression of genes to affect tumorigenesis. Our previous work had demonstrated that a novel lncRNA, LINC02321, was associated with BC prognosis. In this study, A high expression of LINC02321 was found in BC tissues, which was associated with poor prognosis in patients. LINC02321 promoted both proliferation and G1-G0 progression in BC cells, while also inhibited sensitivity to cisplatin. Mechanistically, LINC02321 can bind to RUVBL2 and regulate the expression levels of RUVBL2 protein by affecting its half-life. RUVBL2 is involved in the DNA damage response. The potential of DNA damage repair pathways to exert chemosensitization has been demonstrated in vivo. The rescue experiment demonstrated that RUVBL2 overexpression can markedly abolish the decreased cell proliferation and the increased sensitivity of BC cells to cisplatin caused by LINC02321 knockdown. The results indicate that LINC02321 functions as an oncogene in BC, and may serve as a novel potential target for controlling BC progression and addressing cisplatin resistance in BC therapy.

Biomaterial-Based Sustained-Release Drug Formulations for Localized Cancer Immunotherapy

Cancer immunotherapy has revolutionized clinical cancer treatments by taking advantage of the immune system to selectively and effectively target and kill cancer cells. However, clinical cancer immunotherapy treatments often have limited efficacy and/or present severe adverse effects associated primarily with their systemic administration. Localized immunotherapy has emerged to overcome these limitations by directly targeting accessible tumors via local administration, reducing potential systemic drug distribution that hampers drug efficacy and safety. Sustained-release formulations can prolong drug activity at target sites, which maximizes the benefits of localized immunotherapy to increase the therapeutic window using smaller dosages than those used for systemic injection, avoiding complications of frequent dosing. The performance of sustained-release formulations for localized cancer immunotherapy has been validated preclinically using various implantable and injectable scaffold platforms. This review introduces the sustained-release formulations developed for localized cancer immunotherapy and highlights their biomaterial-based platforms for representative classes, including inorganic scaffolds, natural hydrogels, synthetic hydrogels, and microneedle patches. The design rationale and other considerations are summarized for further development of biomaterials for the construction of optimal sustained-release formulations.

Learning Curve of a Novel Three-Port Laparoscopic Radical Cystectomy with Urinary Diversion: A Single-Center Retrospective Analysis

Objective: Three-port laparoscopic radical cystectomy (LRC) is a novel method of radical cystectomy, which is being spread by our team in primary hospitals in our country. The purpose of this study was to evaluate the learning curve of urologists using this technique for bladder cancer patients. Methods: We retrospectively evaluated clinical data from patients with bladder cancer who received three-port LRC with urinary diversion at our medical center between January 2018 and December 2021. Consecutive cases were grouped according to different surgical years, and perioperative parameters among groups were assessed as variables for the learning curve, including operative time, estimated blood loss (EBL), lymph nodes (LN) yield, and postoperative hospital stay. Results: We assessed 154 patients who were divided into three groups, all of which were comparable in terms of preoperative characteristics. With the increase in surgical experience, the operation time of urologists is obviously reduced (P < .05), especially after 100 surgeries, whereas no statistically significant difference was observed in terms of EBL, LN yield, and postoperative hospital stay in the different surgical experience groups (P > .05). Conclusions: Our early learning curve experience indicates that the three-port LRC with urinary diversion is a safe and feasible technique that can be mastered by urologists after learning from a large sample. Given its advantages in cost and significantly improved learning curve, we recommend this technique to surgeons with extensive laparoscopic experience.

Current advances in the application of nanomedicine in bladder cancer

Bladder cancer is the most common malignant tumor of the urinary system, however there are several shortcomings in current diagnostic and therapeutic measures. In terms of diagnosis, the diagnostic tools currently available are not sufficiently sensitive and specific, and imaging is poor, leading to misdiagnosis and missed diagnoses, which can delay treatment. In terms of treatment, current treatment options include surgery, chemotherapy, immunotherapy, gene therapy, and other emerging treatments, as well as combination therapies. However, the main reasons for poor efficacy and side effects during treatment are the lack of specificity and targeting, improper dose control of drugs and photosensitizers, damage to normal cells while attacking cancer cells, and difficulty in delivering siRNA to cancer cells. Nanomedicine is an emerging approach. Among the many nanotechnologies applied in the medical field, nanocarrier-assisted drug delivery systems have attracted extensive research interest due to their great translational value. Well-designed nanoparticles can deliver agents or drugs to specific cell types within target organs through active targeting or passive targeting (enhanced permeability and retention), which allows for imaging, diagnosis, as well as treatment of cancer. This paper reviews advances in the application of various nanocarriers and their advantages and drawbacks, with a focus on their use in the diagnosis and treatment of bladder cancer.