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Biology subjects

Anami, Y.

Publications and source records attributed to Anami, Y..

3 recordsLinked to original sources

Antibody-drug conjugates targeting EGFR ligand Epiregulin inhibit colorectal tumor growth irrespective of RAS mutational status

As colorectal cancer (CRC) remains a leading cause of cancer-related death, identifying therapeutic targets and approaches is essential to improve patient outcomes. The EGFR ligand epiregulin (EREG) is highly expressed in RAS wildtype and mutant CRC with minimal expression in normal tissues, making it an attractive target for antibody-drug conjugate (ADC) development. In this study, we produced and purified an EREG monoclonal antibody (mAb), H231, that had high specificity and affinity for human and mouse EREG. H231 also internalized to lysosomes, which is important for ADC payload release. ImmunoPET and ex vivo biodistribution studies showed significant tumor uptake of 89Zr-labeled H231 with minimal uptake in normal tissues. H231 was conjugated to either cleavable dipeptide or tripeptide chemical linkers attached to the DNA-alkylating payload duocarmycin DM, and cytotoxicity of EREG ADCs was assessed in a panel of CRC cell lines. EREG ADCs incorporating tripeptide linkers demonstrated the highest potency in EREG-expressing CRC cells irrespective of RAS mutations. Preclinical safety and efficacy studies showed EREG ADCs were well-tolerated, neutralized EGFR pathway activity, caused significant tumor growth inhibition or regression, and increased survival in CRC cell line and patient-derived xenograft models. These data suggest EREG is a promising target for the development of ADCs for treating CRC and other cancer types that express high levels of EREG. While the efficacy of clinically approved anti-EGFR mAbs are largely limited by RAS mutational status, EREG ADCs may show promise for both RAS mutant and wildtype patients, thus improving existing treatment options. Significance: EREG-targeting antibody-drug conjugates demonstrate acceptable safety and robust therapeutic efficacy in RAS mutant and wildtype colorectal cancer, suggesting their potential as an alternative to EGFR-targeted therapy to benefit a broader patient population.

cancer biology↗

Homogeneity of antibody-drug conjugates critically impacts the therapeutic efficacy in brain tumors

Glioblastoma multiforme (GBM) is characterized by aggressive growth and the poorest prognosis of all brain tumor types. Most therapies rarely provide clinically meaningful improvements in outcomes of patients with GBM. Antibody-drug conjugates (ADCs) are emerging chemotherapeutics with stunning success in cancer management. Although promising, clinical studies of three ADCs for treating GBM, including Depatux-M, have been discontinued because of safety concerns and limited therapeutic benefits. Here, we report that ADC homogeneity is a critical parameter to maximize the therapeutic potential in GBM therapy. We demonstrate that homogeneous conjugates generated using our linker show enhanced drug delivery to intracranial brain tumors. Notably, compared to heterogeneous ADCs, including a Depatux-M analog, our ADCs provide greatly improved antitumor effects and survival benefits in orthotopic brain tumor models, including a patient-derived xenograft model of GBM. Our findings warrant the future development of homogeneous ADCs as promising molecular entities toward cures for intractable brain tumors.

bioengineering↗

Antibody-drug conjugates with dual payloads for combating breast tumor heterogeneity and drug resistance

Breast tumors generally consist of a diverse population of cells with varying gene expression profiles. Breast tumor heterogeneity is a major factor contributing to drug resistance, recurrence, and metastasis after chemotherapy. Antibody-drug conjugates (ADCs) are emerging chemotherapeutic agents with striking clinical success, including T-DM1 for HER2-positive breast cancer. However, these ADCs often suffer from issues associated with intratumor heterogeneity. Here, we show that homogeneous ADCs containing two distinct payloads are a promising drug class for addressing this clinical challenge. Our conjugates show HER2-specific cell killing potency, desirable pharmacokinetic profiles, minimal immunogenicity, and marginal toxicity at therapeutic doses. Notably, a dual-drug ADC exerts greater treatment effect and survival benefit than does co-administration of two single-drug variants in a xenograft mouse model representing intratumor HER2 heterogeneity and elevated drug resistance. Our findings highlight the therapeutic potential of the dual-drug ADC format for treating refractory breast cancer and perhaps other cancers.

bioengineering↗