Breast cancer drug also combats other types of cancer

Research reveals that Palbociclib, an oral drug used to combat breast cancer also has the potential to combat lymphoma, sarcoma and teratoma cancers

Palbociclib, whose efficacy in combating breast cancer has been demonstrated alone and in combination with endocrine therapy, also has potential to combat other types of cancer, according to a literature review and additional original research conducted by experts at the Abramson Cancer Center (ACC) in the University of Pennsylvania (Penn) and published in JAMA Oncology.

Palbociclib targets the rapid division of tumour cells by inhibiting the activity of the enzymes CDK4 and CDK6, which propel cell division and increase in number in most cancers. It is the first CDK4/6 inhibitor to be approved for the treatment of breast cancer.

The study’s lead author Amy Clark, an assistant professor of hematology/oncology at Penn’s Perelman School of Medicine and ACC, said: “All living cells undergo cell division and palbociclib’s unique capacity to halt the cell division process (also known as the ‘cell cycle’) has potentially broad applicability.

“Pairing palbociclib with other anti-cancer therapies such as endocrine therapy, chemotherapy and targeted therapy can create a powerful combinatorial effect with real promise for addressing a variety of cancers.”

For example, amplification of CDK4 is reported in a high percentage of melanomas and esophageal cancers.

The study’s senior author, Peter O’Dwyer, a professor of hematology/oncology at Penn and director of the Developmental Therapeutics Program at the ACC, said: “This drug has minor effects on normal cells other than neutrophils (white blood cells) and tumours, it can cause shrinkage or more commonly, arrest of growth. 

“As we discover new functions for the CDK4/6 target of this medicine, we are likely to use it in combinations to make other anti-cancer agents work better.”

In addition to inhibiting the cell cycle, palbociclib has been shown, to alter several recently described non–cell cycle functions of CDK4/6, a finding expected to expand its therapeutic role, O’Dwyer added.

The Penn research team found that in addition to fighting certain types of breast cancer, early trials of palbociclib have shown promise of effectiveness in cases of lymphoma, sarcoma, and teratoma, tumours that while rare, often afflict younger patients.  

Penn Medicine said that combining palbociclib with other anti-cancer agents is also feasible and early results in myeloma and some solid tumours have led to more definitive studies.

Other Penn co-authors of the research are Thomas Karasic, Angela DeMichele, David Vaughn, Mark O’Hara, Rodolfo Perini, Paul Zhang, Priti Lal, Michael Feldman and Maryann Gallagher.