Antibody-Drug Conjugates in Non-Small Cell Lung Cancer: Emergence of a Novel Therapeutic Class

HER3-targeted therapy: the mechanism of drug resistance and the development of anticancer drugs

Human epidermal growth factor receptor 3 (HER3), which is part of the HER family, is aberrantly expressed in various human cancers. Since HER3 only has weak tyrosine kinase activity, when HER3 ligand neuregulin 1 (NRG1) or neuregulin 2 (NRG2) appears, activated HER3 contributes to cancer development and drug resistance by forming heterodimers with other receptors, mainly including epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2). Inhibition of HER3 and its downstream signaling, including PI3K/AKT, MEK/MAPK, JAK/STAT, and Src kinase, is believed to be necessary to conquer drug resistance and improve treatment efficiency. Until now, despite multiple anti-HER3 antibodies undergoing preclinical and clinical studies, none of the HER3-targeted therapies are licensed for utilization in clinical cancer treatment because of their safety and efficacy. Therefore, the development of HER3-targeted drugs possessing safety, tolerability, and sensitivity is crucial for clinical cancer treatment. This review summarizes the progress of the mechanism of HER3 in drug resistance, the HER3-targeted therapies that are conducted in preclinical and clinical trials, and some emerging molecules that could be used as future designed drugs for HER3, aiming to provide insights for future research and development of anticancer drugs targeting HER3.

Emerging strategy for the treatment of urothelial carcinoma: Advances in antibody-drug conjugates combination therapy

Urothelial carcinoma (UC) is a prevalent malignant tumor involving the urinary system. Although there are various treatment modalities, including surgery, chemotherapy, and immune checkpoint inhibitor (ICI) therapy, some patients experience disease recurrence and metastasis with poor prognosis and dismal long-term survival. Antibody-drug conjugates (ADCs), which combine the targeting ability of antibody drugs with the cytotoxicity of chemotherapeutic drugs, have recently emerged as a prominent research focus in the development of individualized precision cancer therapy. Although ADCs have improved the overall response rate in patients with UC, their effectiveness remains limited. Currently, ADC-based combination therapies, particularly ADC combined with ICIs, have demonstrated promising efficacy. This combination approach has advanced the treatment of UC, exhibiting the potential to become the standard first-line therapy for advanced UC in the future. This article reviewed clinical trials involving ADC-based combination therapy for UC and discussed the possible challenges and future perspectives to provide guidance for the clinical treatment of UC.

Anti-angiogenic agents for NSCLC following first-line immunotherapy: Rationale, recent updates, and future perspectives

The implementation of immune checkpoint inhibitors (ICIs), with or without chemotherapy, as first-line treatment for patients who do not have actionable mutations has proved to be a major paradigm shift in the management of advanced non-small cell lung cancer (NSCLC). However, the transition of ICIs, such as pembrolizumab and nivolumab, to a first-line setting has left an unmet need for effective second-line treatment options, which is an area of intense research. In 2020, we reviewed the biological and mechanistic rationale for anti-angiogenic agents in combination with, or following, immunotherapy with the aim of eliciting a so called 'angio-immunogenic' switch in the tumor microenvironment. Here, we review the latest clinical evidence of the benefits of incorporating anti-angiogenic agents into treatment regimens. While there is a paucity of prospective data, several recent observational studies indicate that the marketed anti-angiogenic drugs, nintedanib or ramucirumab, are effective in combination with docetaxel following immuno-chemotherapy. Addition of anti-angiogenics, like bevacizumab, have also demonstrated clinical benefit when combined with first-line immuno-chemotherapy regimens. Ongoing clinical trials are assessing these agents in combination with ICIs, with encouraging early results (e.g., ramucirumab plus pembrolizumab in LUNG-MAP S1800A). Also, several emerging anti-angiogenic agents combined with ICIs are currently being assessed in phase III trials following immunotherapy, including lenvatinib (LEAP-008), and sitravatinib (SAPPHIRE) It is hoped that these trials will help expand second-line treatment options in patients with NSCLC. Areas of focus in the future will include further molecular dissection of the mechanisms of resistance to immunotherapy and the various response-progression profiles to immunotherapy observed in the clinic and the monitoring of the dynamics of immunomodulation over the course of treatment. Improved understanding of these phenomena may help identify clinical biomarkers and inform the optimal use of anti-angiogenics in the treatment of individual patients.