Informed by Cancer Stem Cells of Solid Tumors: Advances in Treatments Targeting Tumor-Promoting Factors and Pathways

Cancer stem cells (CSCs) represent a subpopulation within tumors that promote cancer progression, metastasis, and recurrence due to their self-renewal capacity and resistance to conventional therapies. CSC-specific markers and signaling pathways highly active in CSCs have emerged as a promising strategy for improving patient outcomes. This review provides a comprehensive overview of the therapeutic targets associated with CSCs of solid tumors across various cancer types, including key molecular markers aldehyde dehydrogenases, CD44, epithelial cellular adhesion molecule, and CD133 and signaling pathways such as Wnt/β-catenin, Notch, and Sonic Hedgehog. We discuss a wide array of therapeutic modalities ranging from targeted antibodies, small molecule inhibitors, and near-infrared photoimmunotherapy to advanced genetic approaches like RNA interference, CRISPR/Cas9 technology, aptamers, antisense oligonucleotides, chimeric antigen receptor (CAR) T cells, CAR natural killer cells, bispecific T cell engagers, immunotoxins, drug-antibody conjugates, therapeutic peptides, and dendritic cell vaccines. This review spans developments from preclinical investigations to ongoing clinical trials, highlighting the innovative targeting strategies that have been informed by CSC-associated pathways and molecules to overcome therapeutic resistance. We aim to provide insights into the potential of these therapies to revolutionize cancer treatment, underscoring the critical need for a multi-faceted approach in the battle against cancer. This comprehensive analysis demonstrates how advances made in the CSC field have informed significant developments in novel targeted therapeutic approaches, with the ultimate goal of achieving more effective and durable responses in cancer patients.

Adecatumumab: an anti-EpCAM monoclonal antibody, from the bench to the bedside

IMPORTANCE OF THE FIELD

In developing new anticancer drugs, the identification of relevant targets is a key issue of growing importance. Ideally, an anticancer drug target should be specific to cancer cells, in order to both increase efficacy and decrease toxicity of the compound.

AREAS COVERED IN THIS REVIEW

Epithelial cell adhesion molecule (EpCAM) is a membrane protein with proto-oncogenic properties that is expressed in a number of endothelium-derived cancers and is a promising anticancer drug target. Adecatumumab is a monoclonal, fully human IgG1 antibody that targets EpCAM, development of which is at present reaching Phase III trials.

WHAT THE READER WILL GAIN

From a review of literature, we here update the rationale for using EpCAM as an anticancer target for monoclonal antibodies, with a special focus on adecatumumab. The fully human nature of adecatumumab is also discussed to put the drug in perspective with other related anti-EpCAM monoclonal antibodies, such as edrecolomab and catumaxomab. Adecatumumab studies are recapitulated, in order to provide the reader with a comprehensive view of the development of this promising anticancer agent.

TAKE HOME MESSAGE

Adecatumumab is a promising fully human monoclonal antibody targeting EpCAM which is expressed in almost all adenocarcinomas and its activity is not dependent of K-Ras status.