The lack of increases in circulating endothelial progenitor cell as a negative predictor for pathological response to neoadjuvant chemotherapy in breast cancer patients

Circulating endothelial progenitor cells are a potential surrogate marker for angiogenesis. Little is known about the alteration of circulating endothelial progenitor cell counts during neoadjuvant chemotherapy. Our goal was to reveal the alteration in CEP counts in association with response to neoadjuvant chemotherapy in patients with breast cancer. We measured the number of circulating endothelial progenitor cells (CD31+CD34+CD133+CD45dim) by four-color flow cytometry using blood samples from 57 patients with breast cancer who received neoadjuvant chemotherapy (5-fluorouracil + epirubicin + cyclophosphamide (FEC), docetaxel + cyclophosphamide (TC), cisplatin + docetaxel (TP)). There was no significant difference in the baseline circulating endothelial progenitor cell counts with respect to the clinical and pathological background factors. Circulating endothelial progenitor cell counts increased after the initiation of chemotherapy (pre-1st vs. pre-2nd cycle, p = 0.0035; pre-1st vs. pre-4th cycle, p = 0.047). An increase of circulating endothelial progenitor cell counts from pre-1st to pre-2nd cycle was associated with pCR (p = 0.013 for χ 2 test). A multivariate analysis, including subtype, and clinical response showed that the lack of circulating endothelial progenitor cell increases from pre-1st to pre-2nd cycle was an independent negative predictor of pCR (p = 0.002). Our data suggest that alterations in circulating endothelial progenitor cell counts are associated with treatment response. The circulating endothelial progenitor cell count could be a useful biomarker for monitoring chemotherapeutic response.
Breast cancer: Circulating cell counts predict chemo response Breast cancer patients do better after preoperative chemotherapy if their numbers of circulating endothelial progenitor cells (CEPs) go up. A team from Japan led by Takayuki Ueno from the Kyorin University School of Medicine in Tokyo studied 57 women who underwent neoadjuvant chemotherapy to shrink the size of their tumors before surgery. The researchers measured the number of CEPs—cells that derive from the bone marrow and can help build new blood vessels around tumors—both before and during chemotherapy. They found no link between overall CEP counts and treatment response. However, patients whose CEP numbers went up between cycles of chemotherapy had better outcomes. The authors suggest that CEP counts could be used as a diagnostic tool for predicting responses to neoadjuvant chemotherapy, although larger studies are needed to confirm their initial findings