Susan Band Horwitz is an American biochemist and professor at the Albert Einstein College of Medicine where she holds the Falkenstein chair in Cancer Research as well as co-chair of the department of Molecular Pharmacology. Horwitz is a pioneer in dissecting the mechanisms of action of chemotherapeutic drugs including camptothecin, epipodophyllotoxins, and bleomycin, and taxol. Horwitz's work on taxol in particular has brought her international recognition. Horwitz discovered that taxol binds to microtubules, resulting in arrest of the cell cycle in metaphase. Her work paved the way to using taxol and other microtubule binding agents as chemotherapeutics. Taxol remains widely used today, as a means to treat ovarian, breast, and lung cancer. However, since taxol is in short supply, Horwitz is directing studies in her lab to identify similar therapies in natural products. Personal life and education Susan Band Horwitz was born in Cambridge, Massachusetts in 1937. She spent her childhood in the Boston area and attended a Boston public high school. She went to Bryn Mawr College for her undergraduate studies and graduated with a degree in biology in 1958. Subsequently, Susan moved on to obtain her PhD in biochemistry at Brandeis University. It was here that she studied the activity of enzymes and enzyme kinetics under Nathan O. Kaplan. More specifically, she focused on hexitol dehydrogenases from several bacteria, including Bacillus subtilis and Aerobacta aerogenes. Following the completion of her PhD program, her next venture was in the Pharmacology department as a postdoctoral fellow at Tufts University Medical School under Roy Kisliuk. Here, she looked at bacterial assays to explore anti folate qualities present in novel compounds. She began teaching pharmacology to the dental students at Tufts. In 1965, Susan and her family moved down to Georgia where she accepted a position in the pharmacology department at Emory University Medical School. In 1967, she migrated back north again, this time to New York where she took a job as a research assistant under Arthur Grollman at the Albert Einstein College of Medicine. She has worked for the Albert Einstein College of Medicine ever since. In 1970, she moved to a full-time job as an assistant professor in the department of pharmacology. From 2002 to 2003, she was the president of the American Association for Cancer Research. She has a membership in several different organizations including, The National Academy of Sciences, the Institute of Medicine of the National Academies,