Cinnamon extract exhibits potent anti-proliferative activity by modulating angiogenesis and cyclooxygenase in myeloma cells

• CBPE treatment strongly inhibited the expression of angiogenic factors and cyclooxygenase at mRNA as well as at protein level in a time-dependent manner.
• CBPE besides altering the growth kinetics of cells induces DNA fragmentation resulting in apoptosis.
• Anticancer effects of cinnamon extract appear to be mediated by multiple mechanisms. These include inhibition of angiogenesis, inflammation and apoptosis induction in myeloma cells.
• CBPE could be proposed to be a promising candidate for restricting the growth of myeloma cells.
• CBPE could lead to development of potent anti-cancer agent or complementary and alternative medicines for the treatment of MM.

Cinnamon is one of the most widely used herbal medicines with diverse bioactive effects. However, there is no report in regard to the potential anti-proliferative effects of cinnamon on myeloma cells. In this study, the authors investigated the anti-proliferative potential of cinnamon bark powder extract (CBPE) on myeloma cells specifically focusing on its anti-angiogenic and anti-inflammatory properties. The authors observed inhibition of myeloma cell proliferation by CBPE along with anti-inflammatory and anti-angiogenic effects in a human myeloma cell line RPMI 8226. After 24 h of treatment, CBPE caused approximately 50% inhibition of cell growth in RPMI 8226 cells at a concentration of 72 μg/mL (IC50), compared with the untreated controls. CBPE treatment strongly inhibited expression of angiogenic factors and cyclooxygenase at mRNA as well as at protein level in a time-dependent manner. Treatment with the CBPE resulted in cell cycle arrest in the G0/G1 phase in a time-dependent manner. CBPE besides altering growth kinetics of cells, induces DNA fragmentation resulting in apoptosis. In the treated group, DNA fragmentation increased in a time dependent manner with maximum intensity of labeled nucleotides in cells treated for 72 h as compared to 24 h and 48 h. In conclusion, the anticancer effects of cinnamon extract appear to be mediated by multiple mechanisms. These include inhibition of angiogenesis, inflammation and induction of apoptosis in myeloma cells. CBPE could be considered as a promising candidate for restricting the growth of myeloma cells. Hence, CBPE could lead to the development of an effective anti-cancer agent or herbal medicine for the treatment of MM.