Human Epidermal Growth Factor Receptor 2 in Non-Muscle Invasive Bladder Cancer: Issues in Assessment Methods and Its Role as Prognostic/Predictive Marker and Putative Therapeutic Target: A Comprehensive Review

Clinicopathological characteristics and prognostic significance of HER2 status evaluation in patients with urothelial carcinoma: a retrospective single-center experience in China

Due to the lack of an in-depth evaluation of urothelial carcinoma (UC) HER2 expression in both primary and recurrent UC, we examined possible clinical and pathological variables associated with altered UC HER2 expression. The HER2 status and clinicopathological features of primary UCs and matched recurrences from 2015 to 2023 (n = 1352) were compared by evolution category (stable or altered). In 1352 UC patients, HER2 protein expression was linked with age, histological grade, and recurrence. HER2 was expressed in 794 UC patients (58.7%) (1 + , 2 + , and 3 +). High-level (HER2 scored 2 + and 3 +) HER2 expression does not correlate with gene amplification. Significant differences in HER2 expression exist between initial and recurrent tumors (p < 0.05), including a shift from positive to negative expression. Recurrent UC patients showed associations between HER2 expression, histological grade (p < 0.05), and time to surgical recurrence (p = 0.008). HER2 expression in high-grade UC correlated positively with PD-L1 expression in tumor cells (TC) (rs = 0.222, p = 0.047) and tumor-associated immune cells (IC) (rs = 0.238, p = 0.032), especially in recurrent patients (rs = 0.464, p = 0.022). HER2 expression was associated with the biological behavior and prognosis of UC patients. Increased HER2 expression in recurrent UC indicates a poorer prognosis. Consequently, retesting for HER2 is essential in cases of recurrent UC. The association between HER2 and PD-L1 expression in high-grade, recurrent UC suggests the potential for utilizing ADC alongside immunotherapy.

RC48-ADC combined with tislelizumab as neoadjuvant treatment in patients with HER2-positive locally advanced muscle-invasive urothelial bladder cancer: a multi-center phase Ib/II study (HOPE-03)

Background

Bladder cancer with high expression of human epidermal growth factor receptor-2 (HER2) is related to pathological malignancy and poor prognosis. The standard care for muscle-invasive urothelial bladder cancer (MIBC) is neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC) with pelvic lymph node dissection. For HER2-positive MIBC, the efficacy of cisplatin-based NAC is unsatisfactory, and adverse reactions are inevitable or even intolerable. New regimens with higher efficiency and lower toxicity need to be explored in the neoadjuvant setting for this population.

Methods

HOPE-03 is a multi-center, open-label, single-arm, phase Ib/II study aiming to evaluate the safety and efficacy of RC48-ADC (disitamab vedotin (DV)), a humanized anti-HER2 antibody conjugated with monomethyl auristatin E, and tislelizumab (PD-1 antibody) as a novel neoadjuvant treatment combination in patients with HER2-positive locally advanced urothelial MIBC. Fifty-one patients with cT2-4bN0-3M0-1a pathology- and imaging-diagnosed HER2 positive (immunohistochemistry status 3+ or 2+ or 1+) MIBC were recruited. Of these patients, six were enrolled in the dose-escalation phase (three patients in the RC48-ADC 1.5 mg/kg group and three patients in the 2.0 mg/kg group), and 45 patients were enrolled in the phase II study (the expected recommended phase II dose for RC48-ADC was 2.0 mg/kg). Patients without disease progression received radical cystectomy or bladder-sparing therapies as their preference after neoadjuvant treatment. The primary endpoints were clinical complete remission rate (cCR rate; T0/Ta/Tis), pathological complete remission rate (pCR rate), and safety. The secondary endpoints were overall survival (OS), local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and quality of life.

Discussion

The HOPE-03 trial provides a description of the safety profile of RC-48 and tislelizumab combination in the neoadjuvant treatment of HER2-positive locally advanced urothelial MIBC, and the efficacy is explored as well in this population.

Clinical trial registration

https://www.chictr.org.cn/showproj.html?proj=137111, identifier ChiCTR2200060153.

HER2 positivity predicts BCG unresponsiveness and adaptive immune cell exhaustion in EORTC risk-stratified cohort of bladder cancer

Introduction

Predicting the response to Bacillus Calmette-Guérin (BCG) therapy in high-risk patients with non-muscle invasive bladder cancer (NMIBC) is crucial, as failure may necessitate interventions, such as radical cystectomy or salvage therapy. With the recent classification of genetic class 2a (which has HER2 protein abundance as its signature mutation of ERBB2), evaluating its prognostic role and relationship with BCG response could yield important results.

Methods

This retrospective study included 160 patients with NMIBC who underwent transurethral resection of bladder tumors at Gangneung Asan Hospital between 2000 and 2013 and were stratified based on the European Organization for Research and Treatment of Cancer (EORTC) risk criteria. In addition, we analyzed a subset of 67 patients who had received BCG induction therapy to identify factors predictive of BCG treatment response. Univariate and multivariate analyses were used to assess the impact of clinicopathological factors, HER2 positivity, and EORTC risk on recurrence, progression, survival, and BCG response. Each variable's prognostic significance was determined using the Kaplan-Meier analysis. The tumor microenvironments (TMEs) were evaluated in relation to HER2 and EORTC risk.

Results

Patients with HER2+ had a higher median age, a greater prevalence of high-grade tumors, and more frequent recurrences. The univariate analysis demonstrated that the HER2+, intermediate (vs. low-risk) high (vs. low-risk), and EORTC recurrence risk groups were significantly associated with recurrence. In patients treated with BCG, only the HER2+ status predicted recurrence. In the univariate analysis for progression, age, high EORTC progression risk (vs. low-to-intermediate), HER2+, and programmed death-ligand 1 positive (PD-L1+) were significant factors. In multivariate analyses for progression, age, high EORTC progression risk, and PD-L1+ were significant factors for progression. HER2 expression was associated with the TME, influencing the proportion of PD-L1+ cells, as well as other markers of PD-1, CD8, and Ki67.

Conclusion

The HER2+ status may be related to genetic characteristics that appear more frequently in older age, which suggests a potential for predicting the recurrence and response to BCG treatment. Additionally, analyzing TME trends of aggressive adaptive immune response characterized by HER2 expression provides insight into recurrence and BCG response mechanisms.

Characterization of circSCL38A1 as a novel oncogene in bladder cancer via targeting ILF3/TGF-β2 signaling axis

The regulatory role of circRNAs in cancer metastasis has become a focused issue in recent years. To date, however, the discovery of novel functional circRNAs and their regulatory mechanisms via binding with RBPs in bladder cancer (BC) are still lacking. Here, we screened out circSLC38A1 based on our sequencing data and followed validation with clinical tissue samples and cell lines. Functional assays showed that circSLC38A1 promoted BC cell invasion in vitro and lung metastasis of mice in vivo. By conducting RNA pull-down, mass spectrum, and RIP assays, circSLC38A1 was found to interact with Interleukin enhancer-binding factor 3 (ILF3), and stabilize ILF3 protein via modulating the ubiquitination process. By integrating our CUT&Tag-seq and RNA-seq data, TGF-β2 was identified as the functional target of the circSLC38A1-ILF3 complex. In addition, m6A methylation was enriched in circSLC38A1 and contributed to its upregulation. Clinically, circSLC38A1 was identified in serum exosomes of BC patients and could distinguish BC patients from healthy individuals with a diagnostic accuracy of 0.878. Thus, our study revealed an essential role and clinical significance of circSLC38A1 in BC via activating the transcription of TGF-β2 in an ILF3-dependent manner, extending the understanding of the importance of circRNA-mediated transcriptional regulation in BC metastasis.

Low-dose arsenite causes overexpression of EGF, TGFα, and HSP90 through Trx1-TXNIP-NLRP3 axis mediated signaling pathways in the human bladder epithelial cells

Epidemiological studies have demonstrated an increased incidence of bladder cancer in arseniasis- endemic areas; however, the precise molecular mechanisms remain unknown. Our previous results have shown that the protein levels of EGF, TGFα, and HSP90 in arsenite-treated bladder uroepithelial cells increased markedly and contributed to hyperactivation of EGF receptors. The aim of this study was to further explore the regulatory ways underlying overexpression of EGF, TGFα, and HSP90 in these cells. The present results showed that both Trx and GSH systems were stimulated in arsenite-treated cells, and ROS levels in 2 μM arsenite-treated cells did not changed obviously; however, ROS levels in 4 μM arsenite-treated cells increased significantly. By using the antioxidant and specific inhibitors, we found that in 2 μM arsenite-treated cells, JNK/NF-κB signaling pathway was involved in overexpression of EGF and TGFα, and ERK/NF-κB signaling pathway contributed to HSP90 overexpression, however in 4 μM arsenite-treated cells, both ERK/ and JNK/NF-κB signaling pathways were involved in overexpression of EGF, TGFα, and HSP90, and PI3K/AKT/NF-κB signaling pathway contributed to overexpression of EGF and TGFα. Furthermore, our results also showed that the Trx1-TXNIP-NLRP3 axis was activated in arsenite-treated cells, and played a pivotal role in activation of the signaling pathways involved in overexpression of EGF, TGFα, and HSP90. In conclusion, the Trx1-TXNIP-NLRP3 axis might be activated by arsenite-induced redox imbalance in bladder uroepithelial cells, and mediate the activation of signaling pathways involved in overexpression of EGF, TGFα, and HSP90.

Are We Ready to Implement Molecular Subtyping of Bladder Cancer in Clinical Practice? Part 2: Subtypes and Divergent Differentiation

Following several attempts to achieve a molecular stratification of bladder cancer (BC) over the last decade, a "consensus" classification has been recently developed to provide a common base for the molecular classification of bladder cancer (BC), encompassing a six-cluster scheme with distinct prognostic and predictive characteristics. In order to implement molecular subtyping (MS) as a risk stratification tool in routine practice, immunohistochemistry (IHC) has been explored as a readily accessible, relatively inexpensive, standardized surrogate method, achieving promising results in different clinical settings. The second part of this review deals with the pathological and clinical features of the molecular clusters, both in conventional and divergent urothelial carcinoma, with a focus on the role of IHC-based subtyping.

The Clinical Significance and Prognostic Value of HER2 Expression in Bladder Cancer: A Meta-Analysis and a Bioinformatic Analysis

OBJECTIVE

Human Epidermal Growth Factor Receptor 2 (HER2) is highly expressed in multiple malignancies and associated with patients' prognosis, but its role in bladder cancer (BCa) remains elusive. We conducted this meta-analysis to explore the clinical significance and prognostic value of HER2 in BCa.

METHODS

PubMed was searched for studies published between January 1, 2000 and January 1, 2020. The odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (95%CIs) were used to investigate the relationship between HER2 and BCa pathological features. TCGA was mined for the information regarding as well.

RESULTS

Our study included 14 articles enrolling 1398 people. Expression of HER2 is higher in bladder cancer than in normal tissues. HER2 over-expression is associated with CIS, multifocal tumor, large tumor size, high tumor stage and grade, lymph node metastasis, progression, recurrence and papillary tumor. We could not find a significant association between HER2 expression and survival time in BCa patients.

CONCLUSIONS

Our meta and bioinformatic analysis indicated that HER2 expression was related to pathological malignancy and poor prognosis in BCa.

Study Progress of Noninvasive Imaging and Radiomics for Decoding the Phenotypes and Recurrence Risk of Bladder Cancer

Urinary bladder cancer (BCa) is a highly prevalent disease among aged males. Precise diagnosis of tumor phenotypes and recurrence risk is of vital importance in the clinical management of BCa. Although imaging modalities such as CT and multiparametric MRI have played an essential role in the noninvasive diagnosis and prognosis of BCa, radiomics has also shown great potential in the precise diagnosis of BCa and preoperative prediction of the recurrence risk. Radiomics-empowered image interpretation can amplify the differences in tumor heterogeneity between different phenotypes, i.e., high-grade vs. low-grade, early-stage vs. advanced-stage, and nonmuscle-invasive vs. muscle-invasive. With a multimodal radiomics strategy, the recurrence risk of BCa can be preoperatively predicted, providing critical information for the clinical decision making. We thus reviewed the rapid progress in the field of medical imaging empowered by the radiomics for decoding the phenotype and recurrence risk of BCa during the past 20 years, summarizing the entire pipeline of the radiomics strategy for the definition of BCa phenotype and recurrence risk including region of interest definition, radiomics feature extraction, tumor phenotype prediction and recurrence risk stratification. We particularly focus on current pitfalls, challenges and opportunities to promote massive clinical applications of radiomics pipeline in the near future.

Distinctive morphological and molecular features of urothelial carcinoma with an inverted growth pattern

Urothelial carcinoma with an inverted growth pattern (UC-IGP) is a peculiar entity within the spectrum of urothelial lesions. While efforts have been made over the last few decades to unravel its carcinogenesis and relationship with conventional urothelial carcinoma, the exact classification of inverted urothelial lesions is a matter of debate. The morphological features of UC-IGP pose several issues in differential diagnosis with other mostly benign lesions. Various techniques, including immunohistochemistry, UroVysion, and many molecular methods, have been employed to study the exact nature of this lesion. The aim of this review is to provide a comprehensive overview of the morphological and immunophenotypical aspects of UC-IGP. Moreover, we present and discuss the immunohistochemical and molecular markers involved in diagnosis and prognosis of UC-IGP lesions.

N-Glycoproteomic Profiling Reveals Alteration In Extracellular Matrix Organization In Non-Type Bladder Carcinoma

Treatment of advanced and metastatic bladder carcinoma is often ineffective and displays variable clinical outcomes. Studying this aggressive molecular subtype of bladder carcinoma will lead to better understanding of the pathogenesis which may lead to the identification of new therapeutic strategies. The non-type bladder subtype is phenotypically mesenchymal and has mesenchymal features with a high metastatic ability. Post-translational addition of oligosaccharide residues is an important modification that influences cellular functions and contributes to disease pathology. Here, we report the comparative analysis of N-linked glycosylation across bladder cancer subtypes. To analyze the glycosite-containing peptides, we carried out LC-MS/MS-based quantitative proteomic and glycoproteomic profiling. We identified 1299 unique N-linked glycopeptides corresponding to 460 proteins. Additionally, we identified 118 unique N-linked glycopeptides corresponding to 84 proteins to be differentially glycosylated only in non-type subtypes as compared to luminal/basal subtypes. Most of the altered glycoproteins were also observed with changes in their global protein expression levels. However, alterations in 55 differentially expressed glycoproteins showed no significant change at the protein abundance level, representing that the glycosylation site occupancy was changed between the non-type subtype and luminal/basal subtypes. Importantly, the extracellular matrix organization pathway was dysregulated in the non-type subtype of bladder carcinoma. N-glycosylation modifications in the extracellular matrix organization proteins may be a contributing factor for the mesenchymal aggressive phenotype in non-type subtype. These aberrant protein glycosylation would provide additional avenues to employ glycan-based therapies and may lead to the identification of novel therapeutic targets.