Abstract: The subject invention pertains to compositions and methods for treatment of malignancies and inhibiting the growth of cancer cells, such as multiple myeloma and other hematologic malignancies, using HYD1 peptides. Other aspects of the invention are directed to methods for selection of agents useful in the treatment of malignancies and inhibiting the growth of cancer cells. Further aspects of the invention include methods for determining whether a cancer is sensitive or resistant to treatment with HYD1 peptides based on the presence of certain biomarkers, such as ?4 integrin and CD44 expression.

Abstract: The present invention concerns fragments and variants of the HYD1 peptide; polynucleotides encoding the peptides; host cells genetically modified with the polynucleotides; vectors comprising the polynucleotides; compositions containing these peptides, polynucleotides, vectors, or host cells; and methods of using the peptides, polynucleotides, vectors, and host cells as inhibitors of aberrant cell growth in vitro or in vivo, e.g., as anti-cancer agents for treatment of cancer, such as myeloma. The present invention further includes a method of increasing the efficacy of chemotherapy and radiation therapy, comprising administering an agent that binds ?1 integrin to a patient in need thereof. In one embodiment, the ?1 integrin binding agent is the HYD1 peptide, or a functional fragment or variant thereof.