Complete response to trastuzumab and chemotherapy in recurrent urothelial bladder carcinoma with HER2 gene amplification: A case report

Expression of HER2 in urothelial carcinoma and its significance

Objectives

We explored the expression levels and clinical significance of human epidermal growth factor receptor 2 (HER2) in urothelial carcinoma (UC) tissues.

Materials and methods

Patient data were reviewed, and 111 paraffin specimens of UC obtained from the Department of Urology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, from 2020 to 2021 were collected. Immunohistochemistry was used to detect HER2 protein expression in all UC tumor tissues. The χ 2 and Fisher exact tests were used to analyze the relationship between HER2 protein expression and clinicopathological data (sex, age, histopathological diagnosis, invasiveness, histopathological grade, maximum tumor diameter, muscle invasion, regional lymph node metastasis, and clinical stage).

Results

In this study, 92 cases (82.88%) showed HER2 protein expression, and there was a statistically significant difference in the distribution of HER2 positivity (immunohistochemistry 2+ and 3+) according to the pathological grades of UC (p = 0.021). Human epidermal growth factor receptor 2 positivity was not associated with sex, age, histopathological diagnosis, invasiveness, maximum tumor diameter, muscle invasion, regional lymph node metastasis, or clinical stage (all p < 0.05).

Conclusions

Human epidermal growth factor receptor 2 protein is highly expressed in UC, and its expression may be closely related to the high pathological grade of UC.

Landscape of targeted therapies for advanced urothelial carcinoma

Bladder cancer (BC) is the tenth most common malignancy globally. Urothelial carcinoma (UC) is a major type of BC, and advanced UC (aUC) is associated with poor clinical outcomes and limited survival rates. Current options for aUC treatment mainly include chemotherapy and immunotherapy. These options have moderate efficacy and modest impact on overall survival and thus highlight the need for novel therapeutic approaches. aUC patients harbor a high tumor mutation burden and abundant molecular alterations, which are the basis for targeted therapies. Erdafitinib is currently the only Food and Drug Administration (FDA)-approved targeted therapy for aUC. Many potential targeted therapeutics aiming at other molecular alterations are under investigation. This review summarizes the current understanding of molecular alterations associated with aUC targeted therapy. It also comprehensively discusses the related interventions for treatment in clinical research and the potential of using novel targeted drugs in combination therapy.

Antibody-drug conjugates targeting HER2 for the treatment of urothelial carcinoma: potential therapies for HER2-positive urothelial carcinoma

Urothelial carcinoma (UC) is a common cancer characterized by high morbidity and mortality rates. Despite advancements in treatment, challenges such as recurrence and low response rates persist. Antibody-drug conjugates (ADCs) have emerged as a promising therapeutic approach for various cancers, although their application in UC is currently limited. This review focuses on recent research regarding ADCs designed to treat UC by targeting human epidermal growth factor receptor 2 (HER2), a surface antigen expressed on tumor cells. ADCs comprise three main components: an antibody, a linker, and a cytotoxic payload. The antibody selectively binds to tumor cell surface antigens, facilitating targeted delivery of the cytotoxic drug, while linkers play a crucial role in ensuring stability and controlled release of the payload. Cleavable linkers release the drug within tumor cells, while non-cleavable linkers ensure stability during circulation. The cytotoxic payload exerts its antitumor effect by disrupting cellular pathways. HER2 is commonly overexpressed in UCs, making it a potential therapeutic target. Several ADCs targeting HER2 have been approved for cancer treatment, but their use in UC is still being tested. Numerous HER2 ADCs have demonstrated significant growth inhibition and induction of apoptosis in translational models of HER2-overexpressing bladder cancer. Ongoing clinical trials are assessing the efficacy and safety of ADCs targeting HER2 in UC, with the aim of determining tumor response and the potential of ADCs as a treatment option for UC patients. The development of effective therapies with improved response rates and long-term effectiveness is crucial for advanced and metastatic UC. ADCs targeting HER2 show promise in this regard and merit further investigation for UC treatment.

Efficacy and safety analysis of a HER2-targeting antibody-drug conjugate combined with immune checkpoint inhibitors in solid tumors: a real-world study

BACKGROUND

Disitamab Vedotin is a novel antibody-drug conjugate (ADC) drug targeting HER2, which has shown a potential synergistic effect between Disitamab Vedotin and immune checkpoint inhibitors (ICIs). Therefore, we plan to conduct a retrospective real-world study to evaluate the efficacy and safety of Disitamab Vedotin monotherapy or combined with ICIs in the treatment of advanced or metastatic solid tumors.

METHODS

This retrospective study involved patients with locally advanced or metastatic solid tumors who were treated with Disitamab Vedotin monotherapy or combined with ICIs at West China Hospital of Sichuan University from July 2019 to June 2023. The observation items included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), disease control rate (DCR), and treatment-related adverse events (TRAEs).

RESULTS

This study included 49 patients, out of which 34 patients were treated with Disitamab Vedotin plus ICIs and 15 patients received Disitamab Vedotin alone. In all patients, the median PFS was 10 months. The 6-month and 1-year OS rates were 91.1% and 82.3%, respectively. Eighteen (36.7%) patients achieved a partial response, and sixteen (32.7%) patients had stable disease. The combination therapy of Disitamab Vedotin plus ICIs showed a higher ORR (44.1% vs. 20.0%) and a longer median PFS (14 vs. 8 months) compared to Disitamab Vedotin alone. The median PFS for patients expressed with HER2 2+/3+ was 10 months and was not reached for patients expressed with HER2 0/1+. Grade 3-4 TRAEs occurred in 14.7% of patients who received the combination treatment and in 26.7% of patients who received Disitamab Vedotin alone.

CONCLUSIONS

Our study showed that Disitamab-Vedotin-based treatment, alone or in combination with ICIs, exerted considerable prognosis and good tolerance in patients with locally advanced or metastatic solid tumors, regardless of the HER2 expression levels. Whether combination therapy with ICIs provides greater therapeutic benefits compared to monotherapy needs to be further explored through randomized controlled trials.

Advanced renal pelvis carcinoma patient with an ERBB2 insertion mutation: a case report

The prognosis of renal pelvis cancer is poor and therapeutic options are limited, especially for patients with advanced disease. In this report, we present a case of advanced renal pelvis carcinoma in a male patient in his 60s, characterized by an activating mutation in ERBB2. Clinical evaluation resulted in a pathological diagnosis of renal pelvis carcinoma with liver metastasis. Immunohistochemistry staining results suggested that CK, P63, and PAX8 were positively expressed, while Sy, CK7, CK20, S100, PAX8, and HEP1 were negatively expressed. Furthermore, next-generation sequencing results showed an activating mutation in the ERBB2 gene. The patient initially received a trastuzumab-based combination therapy, which led to a significant reduction in ERBB2 mutation frequency and a stable condition after three treatment cycles. However, following continuous treatment for 4 months, the patient developed drug resistance that resulted in disease relapse. Subsequently, the patient received apatinib treatment, but the therapeutic response was not satisfactory. The patient's condition underwent rapid deterioration and he ultimately succumbed to the disease. This case underscores the potential benefit of trastuzumab for treating ERBB2-mutated advanced renal pelvis cancer, but further highlights that overcoming drug resistance remains a crucial challenge for long-term efficacy.

HER2-targeting antibody-drug conjugate RC48 alone or in combination with immunotherapy for locally advanced or metastatic urothelial carcinoma: a multicenter, real-world study

BACKGROUND

Phase II trials showed the efficacy of anti-HER2 RC48-ADC (disitamab vedotin) for HER2-positive metastatic urothelial carcinoma (UC). This study evaluated RC48 alone verses in combination with immunotherapy for locally advanced or metastatic UC using real-world data.

METHODS

This retrospective, multicenter, real-world study included patients with locally advanced or metastatic UC who received RC48 in five hospitals in China between July 2021 and April 2022. The outcomes were progression-free survival (PFS), overall survival (OS), objective response rate (ORR), disease control rate (DCR), and adverse events.

RESULTS

Thirty-six patients were included. The patients were 47-87 years, and 26 (72.2%) were male. Eighteen patients received RC48 alone, and 18 received RC48 combined with a programmed death-1 antibody. The median PFS was 5.4 months. The median OS was not reached. The 6-month and 1-year PFS rates were 38.8% and 15.5%, respectively. The 1-year OS rate was 79.6%. Fourteen (38.9%) patients achieved a partial response, and the ORR was 38.9%. Eleven patients had stable disease, and the DCR was 69.4%. The median PFS for patients who received RC48 combined with immunotherapy and those who received RC48 alone was 8.5 and 5.4 months, respectively. The main treatment-related adverse events included anemia, hypoesthesia, fatigue, and elevated transaminase. No treatment-related death occurred.

CONCLUSION

RC48 alone or combined with immunotherapy might benefit patients with locally advanced or metastatic UC, regardless of impaired renal function.

Interaction between HER2 and ATM predicts poor survival in bladder cancer patients

Human Epidermal Growth Factor Receptor 2 (HER2) overexpression is considered one of the interesting prognostic biomarkers in bladder cancer. However, the mechanism of bladder cancer development in relation to HER2 status remains to be elucidated. In this study, we investigated HER2-Ataxia telangiectasia mutated (ATM) kinase interaction and their impact on patient survival and cancer aggressiveness. Using the Cancer Genome Atlas (TCGA) cohorts, we demonstrated that ATM expression (protein/mRNA) is increased in HER2 deficient compared with proficient HER2 patients. This finding was then validated using the Gene Expression Omnibus database (GEO). Correlation analysis (using low expression vs high expression as a discriminator) revealed a significant association of ATM low and HER2 high status with several clinicopathological variables such as high tumour grade, late disease stage and tumour shape. Kaplan-Meier survival analysis indicated that ATM low and HER2 high is a powerful prognosticator of both overall survival (OS) and disease-free survival (DFS). Furthermore, using bioinformatics and protein/protein interaction analyses, we identified 66 putative overlapping proteins with direct link between HER2 and ATM most of which are functionally involved in transcription regulation, apoptotic process and cell proliferation. Interestingly, the results showed that these proteins are strongly linked with PI3K-Akt pathway, p53 pathway and microRNAs in cancer. Altogether, our data pinpoint an important biological role of the interconnection between HER2 and ATM. The latter appear to be an independent prognostic biomarker and may serve as targets to develop novel combination therapies to improve the outcome of patients with bladder cancer.

Progress in the Research and Targeted Therapy of ErbB/HER Receptors in Urothelial Bladder Cancer

Bladder cancer is a lethal malignancy and a majority of bladder cancer arise from urothelial cells. Infiltration and metastasis are barriers for the radical cystectomy to achieve favored outcome and are the main cause of death. Systemic therapy, including chemotherapy, targeted therapy, and immunotherapy, is fundamental for these patients. erbB/HER receptors are found to be overexpressed in a subgroup of urothelial carcinoma, targeting erbB/HER receptors in these patients was found to be an efficient way in the era of genetic testing. To evaluate the role of erbB/HER receptors in bladder cancer, we reviewed the literature and ongoing clinical trials as regards to this topic to unveil the context of erbB/HER receptors in bladder cancer, which probably help to solidate the theoretical basis and might instruct further research.

High expression of ERBB2 is an independent risk factor for reduced recurrence-free survival in patients with stage T1 non-muscle-invasive bladder cancer

INTRODUCTION

Molecular markers associated with breast cancer are assumed to be associated with outcome in non-muscle-invasive bladder cancer (NMIBC).

MATERIALS AND METHODS

We retrospectively investigated the association of the mRNA expression of estrogen receptor 1 (ESR1) and 2 (ESR2), progesterone receptor (PGR), MKI67, and HER2 (ERBB2) with recurrence-free (RFS), cancer-specific (CSS), and overall survival (OS) in 80 patients with stage T1 NMIBC.

RESULTS

High expression of ESR2 (P = 0.003), ERBB2 (P < 0.001), and MKI67 (P = 0.029) was associated with shorter RFS. Only high ERBB2 was an independent prognostic factor for reduced RFS (HR = 2.98; P = 0.009). When sub stratifying the cohort, high ESR2 was associated with reduced RFS (P < 0.001), CSS (P = 0.037) and OS (P = 0.006) in patients without instillation therapy. High ESR2 was associated with reduced CSS (P = 0.018) and OS (P = 0.029) in females and with shorter RFS in both sexes (males: P = 0.035; females: P = 0.010). Patients with high ERBB2 showed reduced CSS (P = 0.011) and OS (P = 0.042) in females and reduced CSS (P = 0.012) in those without instillation, while RFS was significantly reduced irrespective of sex or instillation.

CONCLUSION

High mRNA expression of ERBB2 is an independent predictor of reduced RFS in patients with stage T1 NMIBC. High ERBB2 and ESR2 are associated with reduced outcomes, especially in females and patients without instillation therapy.