Antitumor effect of a novel humanized MUC1 antibody-drug conjugate on triple-negative breast cancer

MUC1 as a diagnostic biomarker and siRNA-based therapeutic target in breast cancer: A clinical chemistry perspective

Breast cancer remains the leading cause of cancer mortality in women, and early detection coupled with real-time monitoring of tumor burden are clinical imperatives; yet existing imaging-based screening (e.g., mammography, ultrasound) suffers from sensitivities as low as 60-80% and even lower in dense breasts plus substantial false-positive rates, underscoring the critical need for molecular assays with higher accuracy. Current clinical assays for circulating MUC1 (CA15-3) achieve high specificity but exhibit limited sensitivity in early-stage disease, underscoring a critical unmet need for more sensitive, multiplexed biomarkers to enable timely intervention. Mass spectrometry-based glycoproteomic workflows offer multiplexed quantification of tumour-associated MUC1 glycoforms, substantially improving analytical specificity and dynamic range. Complementary liquid-biopsy platforms that detect anti-MUC1 autoantibodies further extend lead time for recurrence detection. Concurrently, small interfering RNA (siRNA) therapies targeting MUC1 delivered via ionizable lipid nanoparticles demonstrate efficient tumor accumulation, robust mRNA knockdown, and favourable safety in phaseI solid tumor trials. In this review, we critically assess the analytical performance and standardization challenges of current MUC1 assays, evaluate emerging mass spectrometry and immunoarray techniques, and examine chemical and nanocarrier strategies that surmount biological barriers to siRNA delivery. We propose a co-development framework for harmonized companion diagnostics and MUC1-directed RNAi therapeutics under unified regulatory pathways, paving the way for precision, biomarker-driven interventions in breast cancer care.

Patterns of immune evasion in triple-negative breast cancer and new potential therapeutic targets: a review

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer characterized by the absence of progesterone and estrogen receptors and low (or absent) HER2 expression. TNBC accounts for 15-20% of all breast cancers. It is associated with younger age, a higher mutational burden, and an increased risk of recurrence and mortality. Standard treatment for TNBC primarily relies on cytotoxic agents, such as taxanes, anthracyclines, and platinum compounds for both early and advanced stages of the disease. Several targeted therapies, including bevacizumab and sunitinib, have failed to demonstrate significant clinical benefit in TNBC. The emergence of immune checkpoint inhibitors (ICI) has revolutionized cancer treatment. By stimulating the immune system, ICIs induce a durable anti-tumor response across various solid tumors. TNBC is a particularly promising target for treatment with ICIs due to the higher levels of tumor-infiltrating lymphocytes (TIL), increased PD-L1 expression, and higher mutational burden, which generates tumor-specific neoantigens that activate immune cells. ICIs administered as monotherapy in advanced TNBC yields only a modest response; however, response rates significantly improve when ICIs are combined with cytotoxic agents, particularly in tumors expressing PD-L1. Pembrolizumab is approved for use in both early and advanced TNBC in combination with standard chemotherapy. However, more research is needed to identify more potent biomarkers, and to better elucidate the synergism of ICIs with other targeted agents. In this review, we explore the challenges of immunotherapy in TNBC, examining the mechanisms of tumor progression mediated by immune cells within the tumor microenvironment, and the signaling pathways involved in both primary and acquired resistance. Finally, we provide a comprehensive overview of ongoing clinical trials underway to investigate novel immune-targeted therapies for TNBC.

The therapeutic potential of natural metabolites in targeting endocrine-independent HER-2-negative breast cancer

Breast cancer (BC) is a heterogenous disease, with prognosis and treatment options depending on Estrogen, Progesterone receptor, and Human Epidermal Growth Factor Receptor-2 (HER-2) status. HER-2 negative, endocrine-independent BC presents a significant clinical challenge with limited treatment options. To date, promising strategies like immune checkpoint inhibitors have not yielded breakthroughs in patient prognosis. Despite being considered archaic, agents derived from natural sources, mainly plants, remain backbone of current treatment. In this context, we critically analyze novel naturally-derived drug candidates, elucidate their intricate mechanisms of action, and evaluate their pre-clinical in vitro and in vivo activity in endocrine-independent HER-2 negative BC. Since pre-clinical research success often does not directly correlate with drug approval, we focus on ongoing clinical trials to uncover current trends. Finally, we demonstrate the potential of combining cutting-edge technologies, such as antibody-drug conjugates or nanomedicine, with naturally-derived agents, offering new opportunities that utilize both traditional cytotoxic agents and new metabolites.