Titles and Affiliations

Assistant Professor of the Division of Oncological Sciences and CEDAR
Knight Cancer Institute, School of Medicine
Oregon Health and Science University
Portland, Oregon
American Association for Cancer Research

Research area

Understanding how cancer stem cells form and promote recurrence and metastasis.


Breast cancer causes over 40,000 deaths every year in the U.S. In many instances, cancer malignancy is due to a population of cells in the tumor, known as cancer stem cells. Cancer stem cells promote tumor recurrence following treatment and drive metastasis, both determinants of patient survival. How cancer stem cells form is poorly understood. For his American Association for Cancer Research project supported by BCRF, Dr. Saldivar is working to understand how cancer stem cells emerge in breast cancer to ultimately target these cells with new treatments and improve survival.

What's next

Dr. Saldivar has discovered a novel link between an enzyme named ATR and a protein complex called Mediator. Mediator helps determine a cell’s identity, including cancer stem cells, and ATR is likely an important driver of cancer stem cell formation through its link to Mediator. Dr. Saldivar will test whether ATR is required for breast cancer stem cell formation and if activation of MYC, a breast cancer oncogene, requires ATR to promote cancer stem cell formation. Therapeutic drugs that inhibit ATR are being tested in the clinic and could potentially be tailored to target cancer stem cells in patients.


Joshua Saldivar, PhD is an Assistant Professor of the Division of Oncological Sciences and CEDAR at the Knight Cancer Institute, Oregon Health and Science University. Dr. Saldivar earned his PhD at The Ohio State University in biomedical sciences with an emphasis in genetics and his MS and BS at the University of Arkansas, Fayetteville in food science and biochemistry, respectively.

His research focuses on understanding the mechanisms that coordinate DNA replication and transcription and how deregulation of these two fundamental processes is linked to epigenetic reprograming in cancer, with a particular focus on breast cancer. His previous work as a PhD student in the lab of Dr. Kay Huebner centered on understanding the cellular events that initiate replication stress-induced genome instability in precancerous cells. There, he discovered a novel mechanism for the origin of genome instability and the initiation of the preneoplastic process.

BCRF Investigator Since


Donor Recognition

The Pink Agenda Award

Areas of Focus