Breast Cancer Stem Cells May Lead to Improved Treatments

Newly discovered pathway may prove effective target for treatment of triple-negative breast cancer.

An analysis of breast cancer stem cells may pave the way to effective new therapies for triple-negative breast cancer.

A study recently published in Molecular Cancer Research noted the discovery of a new regulatory pathway that influences the development of basal-like breast cancer (BLBC), which may serve as a target for effective new treatments.

The study noted that targeted cancer drugs are typically ineffective in the treatment of BLBC. Exacerbating this problem is the fact BLBC tumors generally metastasize quickly, causing a worse clinical outcome for patients.

The aggressiveness of BLBC may be a result of tumors that carry a higher amount of cancer stem cells (CSCs), which causes tumor recurrence, progression, metastasis, and drug resistance, the researchers wrote.

Investigators from the Boston University School of Medicine found a protein secreted by BLBC cells bolsters cancer stem cells through the activation of a distinct signaling pathway within these cells. This protein, called periostin (POSTN), acts via an integrin receptor found on the surface of numerous BLBC cells.

The researchers found that when POSTN or the integrin receptor were disrupted, there was a significant reduction in CSCs, which limited the development of tumors.

It was further noted that BLBCs with high POSTN levels translate into an increase in key cytokines.

"These findings suggest that BLBC cells have an innate ability to establish a local microenvironment that is supportive of cancer stem cells," said study lead Sam Thiagalingam, PhD.

Incidents of high POSTN levels in BLBC was subsequently linked to a worse clinical prognosis.

"This indicates that POSTN might be clinically relevant, as a biomarker and or a therapeutic target, in the setting of BLBC,” Thiagalingam added.

Whether this treatment strategy can lead to an effective therapeutic option for patients with BLBC and other carcinomas has yet to be determined, with further research necessary.

"Ultimately, eliminating cancer stem cells may represent a viable approach to combating BLBCs and inhibition of POSTN signaling may be one way to achieve this," Thiagalingam concluded.