A Rationally Designed ICAM1 Antibody Drug Conjugate for Pancreatic Cancer

Therapeutically targeting endometrial cancer in preclinical models by ICAM1 antibody-drug conjugates

OBJECTIVE

The incidence of mortality and morbidity from endometrial cancer (EC) is increasing annually, and there is a paucity of effective targeted therapies for the condition. Antibody-drug conjugates (ADCs) represent a promising approach to tumor-targeted therapy. In this study, we aim to identify a novel molecular target for the preclinical development of EC-targeted ADCs.

METHODS

Through quantitative and unbiased bioinformatics analyses intercellular adhesion molecule-1 (ICAM1) was identified as a potential cell membrane target. Two ADCs, ICAM1-MMAE and ICAM1-DXd, were subsequently developed by conjugating ICAM1 monoclonal antibodies with microtubule inhibitors and DNA topoisomerase inhibitors, respectively. The preclinical efficacy and biosafety of these ICAM1 ADCs were validated in both in vitro and in vivo models. Furthermore, transcriptomic analysis was conducted to elucidate the therapeutic effects of the ICAM1 ADCs.

RESULTS

Quantitative flow screening and bioinformatics analyses revealed significant overexpression of ICAM1 in EC. ICAM1-MMAE and ICAM1-DXd were developed using clinically effective linkers and payloads. In preclinical models, ICAM1 ADCs showed superior antitumor efficacy compared to standard chemotherapy, achieving sustained tumor regression with an excellent safety profile in both subcutaneous and orthotopic xenograft models. Transcriptomic analysis further revealed that ICAM1-DXd potently activated tumor immunity.

CONCLUSIONS

ICAM1 was identified as a promising cell membrane protein target for ADC development in EC. As-synthesized ICAM1 ADCs demonstrated potent antitumor activity, favorable biosafety profiles in vitro and in vivo, and the ability to activate tumor immunity. These findings support the potential of ICAM1 ADCs as a therapeutic strategy and warrant further investigation in clinical studies.

Identification of CD66c as a potential target in gastroesophageal junction cancer for antibody-drug conjugate development

BACKGROUND

Gastroesophageal junction (GEJ) cancer exhibits unique biological characteristics and currently lacks specific targeted therapies. Given the clinical efficacy of antibody-drug conjugates (ADCs) in solid tumor treatment, we aimed to identify a novel ADC target and suitable payload for GEJ-targeted therapy.

METHODS

In this study, we conducted bioinformatic analyses of multi-omics data, including transcriptomics, proteomics, and phosphoproteomics, to identify CD66c as a promising ADC target for GEJ cancer. We then engineered a CD66c-directed antibody-drug conjugate (CD66c-DXd) incorporating a GGFG linker. The preclinical efficacy of CD66c-DXd was determined in multi GEJ xenograft models.

RESULTS

Proteomic analyses of 103 cases of GEJ cancer revealed that CD66c expression was significantly higher in tumoral tissues compared to normal tissues. Proteomic and phosphoproteomic analyses identified deruxtecan (DXd) as a potentially potent payload for ADCs targeting GEJ cancer. Furthermore, high CD66c expression in GEJ was associated with a significantly lower proportion of plasma cells. The drug-to-antibody ratio (DAR) of CD66c-DXd was determined to be 3.6. CD66c-DXd effectively and selectively ablated multiple human GEJ cell lines (OE-19, OE33 and SK-GT-4) without affecting non-malignant cells (GES-1) in vitro. Eventually, CD66c-DXd mediated potent and durable tumor regression in vivo with excellent safety profiles.

CONCLUSIONS

This preclinical study provides a strong rationale for the further development of CD66c-DXd as promising therapeutic candidates to treat advanced GEJ cancer. Additionally, the study demonstrates the robustness of the multi-omics data in identifying novel potential ADC targets and payloads.

Exploring the potential mechanisms of Da ChaiHu decoction against pancreatic cancer based on network pharmacology prediction and molecular docking approach

Da ChaiHu decoction (DCHD) is used in Chinese medicine to treat pancreatic cancer (PC), but its exact mechanism is not known. The aim of this study was to investigate the main active ingredients and specific mechanisms of DCHD against PC. Firstly, the active ingredients and targets of DCHD and PC-related targets were searched from the TCMSP, DrugBank, NCBI and GeneCards databases, respectively. The intersected targets of both were then taken to construct a PPI network using STRING, and this network was visualized by Cytoscape 3.8.2. GO and KEGG enrichment analyses of the intersected targets were performed using R 4.2.1 "clusterProfiler", "enrichplot", and "ggplot2" packages. Molecular docking was performed utilizing MOE software to detect the binding capacity between compounds and targets. Cell proliferation, apoptosis, invasion and migration were examined through a CCK8 kit, Muse® Cell Analyzer, transwell and wound healing experiment, respectively. The expression levels of five core targets were assessed by RT-qPCR in PANC-1 cells treated with stigmasterol. Molecular dynamic simulations analysis was conducted to analyze the binding affinities and modes of interaction between molecules and stigmasterol using the GROMACS 5.1.4 program package. In this study, 141 common targets of DCHD and PC were obtained. GO-MF items indicated that DCHD exerts its effects on PC primarily by influencing the binding activity of DNA-binding transcription factors. The KEGG analysis revealed that these genes were implicated in various signaling pathways, including the IL-17 signaling pathway and the PI3K/Akt signaling pathway. Stigmasterol was chosen as the final ingredient for subsequent investigation due to its derivation from herb (Da ChaiHu), its encompassment of more common targets, and the scarcity of existing research on its role in PC. The results of molecular docking and Molecular dynamic simulations analysis showed that stigmasterol had good binding activity with BCL2, and ICAM1. In vitro experiments suggested that stigmasterol could effectively inhibit the proliferation, invasion and migration of PANC-1 cells, and promote cell apoptosis. Moreover, stigmasterol treatment led to the reduced expression of AKT1, HIF1A, BCL2, IL1B, and ICAM1. This study is the first to reveal the main active components and potential mechanisms of DCHD against PC, which provides a theoretical basis for studying the role of DCHD in the treatment of PC. Especially, the anti-PC mechanism of active compound stigmasterol might be associated with inhibiting proliferation, invasion and migration and accelerating apoptosis. Furthermore, five targets (AKT1, HIF1A, BCL2, IL1B, and ICAM1) were identified as key targets of stigmasterol, and the mRNA expressions of these genes were down-regulated by stigmasterol through in vitro experiments.

Pancreatic Cancer: Pathogenesis and Clinical Studies

Pancreatic cancer (PC) is a highly lethal malignancy, with pancreatic ductal adenocarcinoma (PDAC) being the most common and aggressive subtype, characterized by late diagnosis, aggressive progression, and resistance to conventional therapies. Despite advances in understanding its pathogenesis, including the identification of common genetic mutations (e.g., KRAS, TP53, CDKN2A, SMAD4) and dysregulated signaling pathways (e.g., KRAS-MAPK, PI3K-AKT, and TGF-β pathways), effective therapeutic strategies remain limited. Current treatment modalities including chemotherapy, targeted therapy, immunotherapy, radiotherapy, and emerging therapies such as antibody-drug conjugates (ADCs), chimeric antigen receptor T (CAR-T) cells, oncolytic viruses (OVs), cancer vaccines, and bispecific antibodies (BsAbs), face significant challenges. This review comprehensively summarizes these treatment approaches, emphasizing their mechanisms, limitations, and potential solutions, to overcome these bottlenecks. By integrating recent advancements and outlining critical challenges, this review aims to provide insights into future directions and guide the development of more effective treatment strategies for PC, with a specific focus on PDAC. Our work underscores the urgency of addressing the unmet needs in PDAC therapy and highlights promising areas for innovation in this field.

Humanized Anti-MUC16 Antibody-Conjugated Contrast Agents for Magnetic Resonance Imaging of Pancreatic Cancer

Background/Objectives: Pancreatic ductal adenocarcinoma (PDAC) is diagnosed at a late stage with distant metastasis in an overwhelming 50% of cases, and the prognosis is poor. Treating this extremely aggressive disease with standard-of-care therapies has led to modest benefits in overall survival, mainly due to a lack of targeted early treatment modalities, as early detection has not yet been possible. Mucin-16 (MUC16) is a glycoprotein overexpressed in more than 60% of patients with PDAC and is a tumor-specific biomarker. Methods: In this study, a magnetic resonance imaging (MRI) probe to facilitate the detection of early and late lesions of PDAC is developed by conjugating a MUC16-targeted humanized antibody (huAR9.6) with gadolinium. Results: In preclinical mouse models, this MUC16-targeted MRI probe demonstrates effective contrast enhancement in early lesions of PDAC in the subcutaneous setting and allows for the detection of late-stage pancreatic cancer tumors in an orthotopic model. The probe did not induce any toxicity in vital organs at the administered doses. Conclusions: This study establishes that synthesizing a MUC16-targeted MRI probe is feasible and allows for the better high-resolution contrast enhancement of MUC16+ PDAC lesions to facilitate detection and possibly better treatment strategies.

Eliminating VEGFA+ tumor-associated neutrophils by antibody-drug conjugates boosts antitumor immunity and potentiates PD-1 immunotherapy in preclinical models of cervical cancer

Tumor-associated neutrophils (TANs) actively interact with antibody-drug conjugates (ADCs) within the tumor microenvironment (TME), though the detailed mechanisms governing their response to ADC treatment remain to be fully elucidated. Herein, we explored how ICAM1-targeted ADCs affect TAN dynamics in preclinical models of cervical cancer. We discovered that I-DXd, our in-house ADC targeting cervical cancer, effectively eliminates tumor cells through specific antigen recognition while concurrently depleting pro-tumor VEGFA + TANs via Fcγ receptor-mediated phagocytosis. This dual action promotes an immunologically favorable TME. Through comprehensive preclinical studies, we established a foundational understanding of the synergistic benefits of combining I-DXd treatment with PD-1 immune checkpoint inhibition, thereby opening new avenues for therapeutic intervention in advanced cervical cancer.

Utility of 131I-HLX58-Der for the Precision Treatment: Evaluation of a Preclinical Radio-Antibody-Drug-Conjugate Approach in Mouse Models

Purpose

None of the antibody-drug conjugates (ADCs) targeting Claudin 18.2 (CLDN18.2) have received approval from regulatory authorities due to their limited clinical benefits. Leveraging the radiosensitizing ability of Deruxtecan (DXd) and the internal radiation therapy of 131I for tumors, we aimed to develop the first radio-antibody-drug conjugates (RADCs) for the treatment of gastric cancer.

Methods

The CLDN18.2-specific antibody HLX58 was conjugated with the payload DXd through a cleavable maleimide glycynglycyn-phenylalanyn-glycyn (GGFG) peptide linker. HLX58-Der was labeled with 131I to produce RADC-131I-HLX58-Der. HLX58 was labeled with 125I for imaging CLDN18.2-positive tumors, providing a reference for RADC treatment in solid tumors. The antigen-binding properties and biodistribution of the RADC were studied both in vitro and in vivo. The cytotoxic effects of the RADC were evaluated in CLDN18.2-positive tumor cell lines and xenografts.

Results

HLX58 was successfully conjugated with DXd using the cleavable maleimide GGFG peptide linker and labeled with 131I to produce RADC-131I-HLX58-Der. HLX58 was labeled with 125I for imaging CLDN18.2-positive tumors. Both 125I-HLX58 and 131I-HLX58-Der exhibited significant binding affinity for the CLDN18.2-positive cancer cell line. The cytotoxic effect of 131I-HLX58-Der was observed in the CLDN18.2-positive cell line, with an IC50 of 11.28 ng/mL. In terms of cytotoxicity, 131I-HLX58-Der exhibited greater activity compared to HLX58-Der. 125I-HLX58 and 131I-HLX58-Der demonstrated similar biodistribution profiles in CLDN18.2-positive tumor models, achieving 5.72 ± 0.41%ID/g (48 h) and 5.83 ± 0.41%ID/g (72 h) in the tumor tissues postinjection, respectively. The average tumor size in groups treated with 131I-HLX58-Der and HLX58-Der was reduced by factors of 12.15 and 4.80, respectively, compared to the control group. 131I-HLX58-Der demonstrated no toxic effects on hepatorenal function, routine blood tests, or major organs in mice when compared to the control group.

Conclusion

These findings validate the potential of RADCs targeting CLDN18.2 in treating CLDN18.2-expressing solid tumors.

Intercellular adhesion molecule-1 (ICAM-1): From molecular functions to clinical applications in cancer investigation

Intercellular adhesion molecule-1 (ICAM-1) is a versatile molecule that plays a critical role in various physiological and pathological processes, particularly in tumor development where its impact is bidirectional. On the one hand, it augments the immune response by promoting immune cell migration, infiltration, and the formation of immunological synapses, thus facilitating potent antitumor effects. Simultaneously, it contributes to tumor immune evasion and influences metastasis by mediating transendothelial migration (TEM), epithelial-to-mesenchymal transition (EMT), and epigenetic modification of tumor cells. Despite its significant potential, the full clinical utility of ICAM-1 has yet to be fully realized. In this review, we thoroughly examine recent advancements in understanding the role of ICAM-1 in tumor development, its relevance in predicting therapeutic efficacy and prognosis, as well as the progress in clinical translational research on anti-ICAM-1-based therapies, encompassing including monoclonal antibodies, immunotherapy, antibody-drug conjugate (ADC), and conventional treatments. By shedding light on these innovative strategies, we aim to underscore ICAM-1's significance as a valuable and multifaceted target for cancer treatment, igniting enthusiasm for further research and facilitating translation into clinical applications.

Antibody-Drug Conjugates and Their Potential in the Treatment of Patients with Biliary Tract Cancer

Background: Biliary tract cancers (BTCs) are aggressive in nature, often presenting asymptomatically until they are diagnosed at an advanced stage. Surgical resection or liver transplantation are potential curative options. However, a large proportion of patients present with incurable locally advanced or metastatic disease and most of these patients are only eligible for palliative chemotherapy or best supportive care. More recently, targeted therapies have proven beneficial in a molecularly selected subgroup of patients with cholangiocarcinoma who have progressed on previous lines of systemic treatment. However, only a minority of patients with BTCs whose tumours harbour specific molecular alterations can access these therapies. Methods: In relation to ADCs, studies regarding use of antibody-drug conjugates in cancer, particularly in BTCs, were searched in Embase (1974 to 2024) and Ovid MEDLINE(R) (1946 to 2024) to obtain relevant articles. Examples of current clinical trials utilising ADC treatment in BTCs were extracted from the ClinicalTrials.gov trial registry. Conclusions: Overall, this review has highlighted that ADCs have shown encouraging outcomes in cancer therapy, and this should lead to further research including in BTCs, where treatment options are often limited. The promising results observed with ADCs in various cancers underscore their potential as a transformative approach in oncology, warranting continued exploration and development and the need for education on the management of their specific toxicities. By addressing current challenges and optimising ADC design and application, future studies could potentially improve treatment outcomes for patients with BTCs and beyond, potentially in both early and advanced stage settings.

Epigenetic Reprogramming Potentiates ICAM1 Antibody Drug Conjugates in Preclinical Models of Melanoma

Therapeutic benefits and underlying biomechanism(s) of antibody drug conjugates (ADC) in combination with other targeted therapeutics are largely unknown. Here, the synergy between ADC and epigenetic drug decitabine (DAC), a clinically approved DNA methylation inhibitor, in multiple preclinical models of melanoma specifically investigated. Mechanistically, the underlying biomechanisms of how DAC cooperatively worked with ICAM1 antibody conjugated DNA topoisomerase I inhibitor DXd (I1-DXd) is elucidated. DAC treatment significantly enhanced anti-tumor efficacy of I1-DXd by upregulating antigen expression, enhancing antibody internalization and potentiating tumor sensitivity by epigenetically reprogramming of melanoma. Meanwhile, I1-DXd/DAC combination also exerted regulatory effects on tumor microenvironment (TME) by enhancing tumor infiltration of innate and adaptive immune cells and improving penetration of ADCs with a boosted antitumor immunity. This study provides a rational ADC combination strategy for solid tumor treatment.

Antibody drug conjugates: hitting the mark in pancreatic cancer?

Pancreatic cancer is one of the most common causes of cancer-related death, and the 5-year survival rate has only improved marginally over the last decade. Late detection of the disease means that in most cases the disease has advanced locally and/or metastasized, and curative surgery is not possible. Chemotherapy is still the first-line treatment however, this has only had a modest impact in improving survival, with associated toxicities. Therefore, there is an urgent need for targeted approaches to better treat pancreatic cancer, while minimizing treatment-induced side-effects. Antibody drug conjugates (ADCs) are one treatment option that could fill this gap. Here, a monoclonal antibody is used to deliver extremely potent drugs directly to the tumor site to improve on-target killing while reducing off-target toxicity. In this paper, we review the current literature for ADC targets that have been examined in vivo for treating pancreatic cancer, summarize current and on-going clinical trials using ADCs to treat pancreatic cancer and discuss potential strategies to improve their therapeutic window.

Development of potent antibody drug conjugates against ICAM1+ cancer cells in preclinical models of cholangiocarcinoma

As a highly lethal adenocarcinoma of the hepatobiliary system, outcomes for cholangiocarcinoma (CCA) patients remain prominently poor with a 5-year survival of <10% due to the lack of effective treatment modalities. Targeted therapeutics for CCA are limited and surgical resection of CCA frequently suffers from a high recurrence rate. Here we report two effective targeted therapeutics in this preclinical study for CCA. We first performed a quantitative and unbiased screening of cancer-related antigens using comparative flow cytometry in a panel of human CCA cell lines, and identified intercellular adhesion molecule-1 (ICAM1) as a therapeutic target for CCA. After determining that ICAM1 has the ability to efficiently mediate antibody internalization, we constructed two ICAM1 antibody-drug conjugates (ADCs) by conjugating ICAM1 antibodies to different cytotoxic payloads through cleavable chemical linkers. The efficacies of two ICAM1 ADCs have been evaluated in comparison with the first-line chemodrug Gemcitabine in vitro and in vivo, and ICAM1 antibodies coupled with warhead DX-8951 derivative (DXd) or monomethyl auristatin E (MMAE) elicit a potent and consistent tumor attenuation. In summary, this study paves the road for developing a promising targeted therapeutic candidate for clinical treatment of CCA.

ICAM1 antibody drug conjugates exert potent antitumor activity in papillary and anaplastic thyroid carcinoma

Treatment options for anaplastic thyroid cancer (ATC) and refractory papillary thyroid carcinoma (PTC) are limited and outcomes remain poor. In this study, we determined via bioinformatic expression analyses and immunohistochemistry staining that intercellular adhesion molecule-1(ICAM1) is an attractive target for ATC and PTC. We designed and engineered two ICAM1-directed antibody-drug conjugate (I1-MMAE and I1-DXd), both of which potently and selectively ablate multiple human ATC and PTC cell lines without affecting non-plastic cells in vitro. Furthermore, I1-MMAE and I1-DXd mediated a potent tumor regression in ATC and PTC xenograft models. To develop a precision medicine, we also explored magnetic resonance imaging (MRI) as a non-invasive biomarker detection method to quantitatively map ICAM1 antigen expression in heterogeneous thyroid tumors. Taken together, this study provides a strong rationale for the further development of I1-MMAE and I1-DXd as promising therapeutic candidates to treat advanced PTC and ATC.

Revealing the Role of Zinc Ions in Atherosclerosis Therapy via an Engineered Three-Dimensional Pathological Model

An incomplete understanding of the cellular functions and underlying mechanisms of zinc ions released from zinc-based stents in atherosclerosis (AS) therapy is one of the major obstacles to their clinical translation. The existing evaluation methodology using cell monolayers has limitations on accurate results due to the lack of vascular architectures and pathological features. Herein, the authors propose a 3D biomimetic AS model based on a multi-layer vascular structure comprising endothelial cells and smooth muscle cells with hyperlipidemic surroundings and inflammatory stimulations as AS-prone biochemical conditions to explore the biological functions of zinc ions in AS therapy. Concentration-dependent biphasic effects of zinc ions on cell growth are observed both in cell monolayers and 3D AS models. Nevertheless, the cells within 3D AS model exhibit more accurate biological assessments of the zinc ions, as evidenced by augmented pathological features and significantly higher half-maximal inhibitory concentration values against zinc ions. Based on such a developed 3D biomimetic AS model, the inhibitory effects on the deoxyribonucleic acid (DNA) synthesis, significantly influenced biological processes like cell motility, proliferation, and adhesion, and several potential bio-targets of zinc ions of cells are revealed.

A rationally designed ICAM1 antibody drug conjugate eradicates late-stage and refractory triple-negative breast tumors in vivo

Triple-negative breast cancer (TNBC) remains the most lethal form of breast cancer, and effective targeted therapeutics are in urgent need to improve the poor prognosis of TNBC patients. Here, we report the development of a rationally designed antibody drug conjugate (ADC) for the treatment of late-stage and refractory TNBC. We determined that intercellular adhesion molecule-1 (ICAM1), a cell surface receptor overexpressed in TNBC, efficiently facilitates receptor-mediated antibody internalization. We next constructed a panel of four ICAM1 ADCs using different chemical linkers and warheads and compared their in vitro and in vivo efficacies against multiple human TNBC cell lines and a series of standard, late-stage, and refractory TNBC in vivo models. An ICAM1 antibody conjugated with monomethyl auristatin E (MMAE) via a protease-cleavable valine-citrulline linker was identified as the optimal ADC formulation owing to its outstanding efficacy and safety, representing an effective ADC candidate for TNBC therapy.

Drug Delivery Strategies for the Treatment of Pancreatic Cancer

Pancreatic cancer is fast becoming a global menace and it is projected to be the second leading cause of cancer-related death by 2030. Pancreatic adenocarcinomas, which develop in the pancreas' exocrine region, are the predominant type of pancreatic cancer, representing about 95% of total pancreatic tumors. The malignancy progresses asymptomatically, making early diagnosis difficult. It is characterized by excessive production of fibrotic stroma known as desmoplasia, which aids tumor growth and metastatic spread by remodeling the extracellular matrix and releasing tumor growth factors. For decades, immense efforts have been harnessed toward developing more effective drug delivery systems for pancreatic cancer treatment leveraging nanotechnology, immunotherapy, drug conjugates, and combinations of these approaches. However, despite the reported preclinical success of these approaches, no substantial progress has been made clinically and the prognosis for pancreatic cancer is worsening. This review provides insights into challenges associated with the delivery of therapeutics for pancreatic cancer treatment and discusses drug delivery strategies to minimize adverse effects associated with current chemotherapy options and to improve the efficiency of drug treatment.

Generation of high affinity ICAM-1-specific nanobodies and evaluation of their suitability for allergy treatment

The nasal cavity is an important site of allergen entry. Hence, it represents an organ where trans-epithelial allergen penetration and subsequent IgE-mediated allergic inflammation can potentially be inhibited. Intercellular adhesion molecule 1 (ICAM-1) is highly expressed on the surface of respiratory epithelial cells in allergic patients. It was identified as a promising target to immobilize antibody conjugates bispecific for ICAM-1 and allergens and thereby block allergen entry. We have previously characterized a nanobody specific for the major birch pollen allergen Bet v 1 and here we report the generation and characterization of ICAM-1-specific nanobodies. Nanobodies were obtained from a camel immunized with ICAM-1 and a high affinity binder was selected after phage display (Nb44). Nb44 was expressed as recombinant protein containing HA- and His-tags in Escherichia coli (E.coli) and purified via affinity chromatography. SDS-PAGE and Western blot revealed a single band at approximately 20 kDa. Nb44 bound to recombinant ICAM-1 in ELISA, and to ICAM-1 expressed on the human bronchial epithelial cell line 16HBE14o- as determined by flow cytometry. Experiments conducted at 4°C and at 37°C, to mimic physiological conditions, yielded similar percentages (97.2 ± 1.2% and 96.7 ± 1.5% out of total live cells). To confirm and visualize binding, we performed immunofluorescence microscopy. While Texas Red Dextran was rapidly internalized Nb44 remained localized on the cell surface. Additionally, we determined the strength of Nb44 and ICAM-1 interaction using surface plasmon resonance (SPR). Nb44 bound ICAM-1 with high affinity (10-10 M) and had slow off-rates (10-4 s-1). In conclusion, our results showed that the selected ICAM-1-specific nanobody bound ICAM-1 with high affinity and was not internalized. Thus, it could be further used to engineer heterodimers with allergen-specific nanobodies in order to develop topical treatments of pollen allergy.

Rational Design and Systemic Appraisal of an EGFR-Targeting Antibody-Drug Conjugate LR-DM1 for Pancreatic Cancer

By harnessing the payload DM1 and a monoclonal antibody LR004 through a noncleavable linker succinimidyl-4-(N-maleimidomethyl)-cyclohexane-1-carboxylate, we designed and evaluated an antibody-drug conjugate LR-DM1 with an appropriate drug-antibody ratio of 3.6. LR-DM1, which was targeted toward the epidermal growth factor receptor for pancreatic cancer, exhibited potent antiproliferation activity in vitro with a half-maximal inhibitory concentration value of 7.03 nM for Capan-2 cells. Particularly, it displayed prominent tumor growth inhibition in vivo under 20 mg/kg LR-DM1 dosage in a single administration or multiple administrations without apparent abnormality of pathological observation. Moreover, LR-DM1 possessed a relatively broad therapeutic index with a half-lethal dose above 300 mg/kg, which was over 15-fold higher than the highest administration dosage of 20 mg/kg. This initial study on LR-DM1 holds promise for further development of a new antibody drug conjugate that is transformative for treatment of patients concerned.

Bispecific CAR T Cells against EpCAM and Inducible ICAM-1 Overcome Antigen Heterogeneity and Generate Superior Antitumor Responses

Adoptive transfer of chimeric antigen receptor (CAR) T cells has demonstrated unparalleled responses in hematologic cancers, yet antigen escape and tumor relapse occur frequently. CAR T-cell therapy for patients with solid tumors faces even greater challenges due to the immunosuppressive tumor environment and antigen heterogeneity. Here, we developed a bispecific CAR to simultaneously target epithelial cell adhesion molecule (EpCAM) and intercellular adhesion molecule 1 (ICAM-1) to overcome antigen escape and to improve the durability of tumor responses. ICAM-1 is an adhesion molecule inducible by inflammatory cytokines and elevated in many types of tumors. Our study demonstrates superior efficacy of bispecific CAR T cells compared with CAR T cells targeting a single primary antigen. Bispecific CAR T achieved more durable antitumor responses in tumor models with either homogenous or heterogenous expression of EpCAM. We also showed that the activation of CAR T cells against EpCAM in tumors led to upregulation of ICAM-1, which rendered tumors more susceptible to ICAM-1 targeting by bispecific CAR T cells. Our strategy of additional targeting of ICAM-1 may have broad applications in augmenting the activity of CAR T cells against primary tumor antigens that are prone to antigen loss or downregulation.

Antibody-Drug Conjugates: Functional Principles and Applications in Oncology and Beyond

In the era of precision medicine, antibody-based therapeutics are rapidly enriched with emerging advances and new proof-of-concept formats. In this context, antibody-drug conjugates (ADCs) have evolved to merge the high selectivity and specificity of monoclonal antibodies (mAbs) with the cytotoxic potency of attached payloads. So far, ten ADCs have been approved by FDA for oncological indications and many others are currently being tested in clinical and preclinical level. This paper summarizes the essential components of ADCs, from their functional principles and structure up to their limitations and resistance mechanisms, focusing on all latest bioengineering breakthroughs such as bispecific mAbs, dual-drug platforms as well as novel linkers and conjugation chemistries. In continuation of our recent review on anticancer implication of ADC's technology, further insights regarding their potential usage outside of the oncological spectrum are also presented. Better understanding of immunoconjugates could maximize their efficacy and optimize their safety, extending their use in everyday clinical practice.