Abstract
Purpose: :
Uveal Melanoma (UM) is the most common malignant intra–ocular tumour in adults. Despite the high accuracy of clinical diagnosis and advances in local treatment, more than 50% of UM patients develop metastasis within ten years of initial diagnosis. Curcumin is a potent antioxidant derived from the Indian spice turmeric and has been shown to have potent anti–inflammatory, anti–carcinogenic, and anti–metastatic activities. Curcumin inhibits cancer formation by up–regulation of carcinogen detoxifying enzymes, induction of apoptosis, inhibition of angiogenesis as well as suppression of cyclooxygenase–2. The aim of this study was to investigate the effect of Curcumin on the proliferation rates of four UM cell lines.
Methods: :
Four human UM cell lines (92.1, SP6.5, MKT–BR, OCM–1) were grown to confluence in RPMI 1640 medium supplemented with 5% Fetal Bovine Serum. Cells were trypsinized, counted, and seeded at a concentration of five thousand cells per well in two ninety–six well plates. Curcumin was added to each cell line in a dilution from 100 uMolar to 1–nMolar concentrations, wells where only RPMI was added were used as a control. Cells were allowed to incubate for 48 hours following the addition of Curcumin to the wells. Cells were observed twice daily. The total protein content of each well was then assessed as per the National Cancer Institute protocol for Sulforhodamine–B. Results per condition were spectrophotometrically measured at a wavelength of 570 nm. The student T test was used to compare the results from each concentration against the control. To further evaluate apoptosis as a possible mechanism of an action by Curcumin the cells were observed daily to check for continued adherence to the plate.
Results: :
The four UM cell lines treated with Curcumin showed a statistically significant decrease in their proliferation rates at 100 and 10 uMolar concentrations (p < 0.001). This decrease of proliferation was consistent for the four UM cell lines, regardless of their original proliferation rates. The addition of 100 uMolar Curcumin resulted in four–fold decrease in the proliferation rates of all four uveal melanoma cell lines. All cell lines remained adherent to the plate throughout their exposure to Curcumin
Conclusions: :
The use of Curcumin led to a significant decrease in the proliferation rates of four uveal melanoma cell lines regardless of their metastatic potential. This decrease in proliferation rate may be due to the apoptotic effect of Curcumin in melanoma cells. Curcumin could be used as a potent therapeutic agent for the treatment of metastatic uveal melanoma.
Keywords: melanoma • proliferation • tumors