untitled 4 | CANCER DISCOVERY�JANUARY 2013 www.aacrjournals.org NEWS IN BRIEF CDK Inhibitor Triples PFS in Breast Cancer Women with estrogen receptor (ER)– positive breast cancer who took an investigational drug targeting cyclin- dependent kinases 4 and 6 (CDK4/6) in combination with the aromatase inhibitor letrozole experienced a “dra- matic and clinically meaningful effect,” researchers reported on December 5 at the 2012 Cancer Therapy and Research Center (CTRC) and American Associa- tion for Cancer Research (AACR) San Antonio Breast Cancer Symposium in Texas. Based on the positive results, these researchers expect to launch a phase III trial of the agent in 2013. In the current phase II study, patients who took Pfi zer’s CDK4/6 inhibitor PD-0332991 with letrozole (Femara; Novartis) achieved a progression-free survival (PFS) period of 26.1 months compared with 7.5 months for patients who were treated with letrozole alone. “This was a welcome result,” commented Norman Sharpless, MD, deputy director of the Lineberger Comprehensive Cancer Center at the University of North Caro- lina (UNC) at Chapel Hill, who was not associated with the study. “A tripling of PFS in this disease is a great fi nding.” CDKs, which participate in cell prolif- eration, tend to be overactive in cancer. Richard Finn, MD, associate professor of medicine at the Jonsson Comprehensive Cancer Center at the University of California, Los Angeles, and the study’s principal investigator, explained that the primary function of CDK4/6 is to phosphorylate the retinoblastoma (RB) protein, which ordinarily blocks early events in the cell cycle. Phosphorylation inactivates RB so that cells can continue to divide. In some cancers, however, CDK4/6 hypherphosphorylates RB, which can lead to uncontrolled cell growth. By inhibiting CDK4/6, Pfi zer’s experi- mental drug prevents RB hyperphos- phorylation. Moreover, Finn added, it has minimal side effects. According to Finn, preclinical stud- ies indicate that only ER-positive breast cancer cells had robust responses to PD-0332991. “ER positivity appears to be a marker for an intact RB pathway,” he said. That’s noteworthy, UNC’s Sharp- less added, given that RB loss occurs in roughly 10% of all cancers. “The drug won’t work in patients who lack the RB pathway,” he noted, “so that gives us a good negative biomarker for who won’t respond to treatment. What we need now is a better posi- tive biomarker to identify those who might respond best in breast cancer and other cancer types.” ■ Surveillance Network Aids Prostate Research Up to 50% of men diagnosed with prostate cancer have a form of the disease that grows so slowly that it’s unlikely to ever threaten their health if left untreated. Unfortunately, physicians currently have no precise way to determine which patients can forego treatment. “We need to fi nd out whether a tumor is a wolf in sheep’s clothing or if it’s really a sheep,” says Stuart Holden, MD, director of Cedars-Sinai’s Louis Warschaw Prostate Cancer Center in Los Angeles, CA, and medical director for the Prostate Cancer Foundation, a philanthropic organization that funds research on the disease. Thanks to a $5-million grant from the foundation, researchers from Johns Hopkins Medicine in Baltimore, MD, and colleagues at Cedars-Sinai have launched the National Proactive Surveil- lance Network (NPSN), a repository of patient information that will advance understanding of who needs treatment. Patients at the 2 institutions who are diagnosed with early-stage, low-volume prostate cancer will be invited to join the program; other institutions will be added to the network in mid- to late 2013. Patients pursuing proactive surveil- lance defer treatments such as surgery and radiation therapy. Instead, they are closely monitored with physical exams and medical tests every 6 months and a prostate biopsy every year. If cancer progresses, they may opt for treat- ment. This strategy is also called active surveillance, expectant management, or watchful waiting. Participants regularly complete detailed lifestyle and nutrition ques- tionnaires, and their blood and urine samples and biopsy tissue are banked PEOPLE Glenn Dranoff, MD, a professor of medicine at Dana- Farber Cancer Institute and Harvard Medical School in Boston, MA, has been named the founding editor-in-chief of Cancer Immunology Research. Published by the American Association for Cancer Research, the journal will launch online at the organiza- tion’s annual meeting in April, followed by monthly print issues beginning in June. The leader of the Dana-Farber/ Harvard Cancer Center Program in Cancer Immunology, Dranoff has devoted his research efforts to under- standing tumor immunity and to the development of cancer vaccines. Karen E. Knudsen, PhD, began a 5-year term as editor-in-chief of Molecular Cancer Research this month. She succeeds Michael B. Kastan, MD, PhD, executive director of the Duke Cancer Institute in Durham, NC. Knudsen is a professor in the depart- ments of cancer biology, urology, and radiation oncology at Philadelphia’s Thomas Jefferson University and deputy director for basic science at the affili- ated Kimmel Cancer Center. In addition to authoring book chapters and dozens of peer-reviewed articles, she has held several leadership roles on scientific publications, including Cancer Research. Richard Nakamura, PhD, has been chosen as the new director of the NIH’s Center for Scientific Review (CSR). He will lead 450 scientists and administrative staff, overseeing their efforts to manage 80,000 NIH grant applications a year, the majority of which are reviewed by CSR peer review groups. The CSR holds 1,600 review meetings a year. Prior to joining the CSR in 2011, Nakamura spent 32 years at the National Institute of Mental Health, serving as both its scientific and deputy director. 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