Evaluation of Curcumin Therapeutic Effects on Histological Subtypes of Canine Mammary Gland Tumours.

Canine mammary gland tumors (CMGTs) are the most frequent types of cancer in bitches and proposed as a model of human breast cancer. The anticancer effect of curcumin on human breast cancer has been extensively studied. The aim of this study was to evaluate the therapeutic effect of curcumin in two different histologies (simple carcinoma [SC] and squamous cell carcinoma [SCC]) of CMGTs. Primary canine mammary cells were isolated from the tumoral tissues surgically resected from two bitches (Case 1 and Case 2). Cell viability, apoptotic percentage, cell cycle progression and the changes in the cell morphology were evaluated. Curcumin inhibited the growth of both SC (Case 1) and SCC (Case 2) cells. However, Case 1 cells (43.48% ± 3.87% at 0.5 µM) were more sensitive to curcumin than Case 2 cells (59.36% ± 2.09% at 0.5 µM). Curcumin induced total apoptotic cell death through G0/G1 arrest, and this effect was more profound in Case 1 cells. Furthermore, cytoplasmic vacuolization, apoptotic bodies and membrane blebbing were observed in both cells following curcumin treatment. Our findings provide a novel approach for the effects of curcumin as a natural compound on CMGTs. Further investigations should be performed to investigate the molecular mechanisms of the differences in curcumin efficacy for different histological subtypes.

Efficacy of 5-aminolevulinic acid-based photodynamic therapy in different subtypes of canine mammary gland cancer cells.

Canine mammary gland tumors (CMGTs) are heterogeneous disease and subclassified [sarcomas (S), carcinomas (C), and carcinosarcomas (CS)] according to histopathological differentiation. Photodynamic therapy (PDT) is a promising treatment strategy based on the use of a photosensitizer (PS) activated by light. However, the therapeutic potential of PDT in the treatment of CMGTs has not been investigated, yet. Therefore, the aim of this study was to determine the in vitro protocol of 5-ALA-based-PDT for the treatment of three subtypes of CMGTs, for the first time. The intracellular PpIX florescence intensity was measured for 5-ALA (0.5 and 1 mM). After irradiation with different light doses (6, 9, 12, 18, and 24 J/cm2) for two different modes [continuous wave (CW) and pulse radiation (PR)], the cytotoxic effects of 5-ALA (0.5 and 1 mM) on the subtypes (C, S, and CS) of CMGTs were analyzed by WST-1. Finally, the optimal PDT treatment protocol was validated through Annexin V and AO/EtBr staining. Our results showed that 1 mM 5-ALA for 4-h incubation was the best treatment condition in all subtypes of CMGTs due to higher intracellular PpIX level. After irradiation with different light doses, PR mode was more effective in S primary cells at 9 J/cm2. However, a significant decrease in the viability of C and CS cells was detected at 12 /cm2 in CW mode (p < 0.05). Additionally, 1 mM 5-ALA induced apoptotic cell death in each subtype of CMGTs. Our preliminary findings suggest that (i) each subtype of CMGTs differentially responds to PDT and (ii) the light dose and mode could play an important role in the effective PDT treatment. However, further studies are needed to investigate the role of the different light sources and PDT-based apoptotic cell death in CMGTs cells.

Vulpinic acid as a natural compound inhibits the proliferation of metastatic prostate cancer cells by inducing apoptosis.

BACKGROUND: Lichen secondary metabolites have drawn considerable attention in recent years due to the limitations of current treatment options. Vulpinic acid (VA) obtained from Letharia vulpina lichen species exerts a remarkable cytotoxic effect on different cancer types. However, the therapeutic efficacy of VA in metastatic prostate cancer (mPC) cells has not been investigated. In the present study, we aimed to identify VA-mediated cytotoxicity in PC-3 mPC cells compared with control cells. METHODS AND RESULTS: After identifying the cytotoxic concentrations of VA, VA induced apoptosis was analyzed by Annexin V, cell cycle, acridine orange and propidium iodide staining and RT-PCR analysis. Our findings showed that VA significantly decreased the viability of PC-3 cells (p < 0.01) and caused a considerable early apoptotic effects through G0/G1 arrest, nuclear blebbing and the activation of particularly initiator caspases. CONCLUSIONS: Therefore, VA may be a potential treatment option for mPC patients. However, the underlying molecular mechanisms of VA-induced apoptosis with advanced analysis should be further investigated.

Investigation of LED-based photodynamic therapy efficiency on breast cancer cells.

Photodynamic therapy (PDT) is based on special light source, photosensitizer (PS), and in the presence of oxygen. Different light sources have been used for PDT applications. Recent studies have focused on LED light sources for PDT applications due to reducing the cost of laser-based PDT and providing easy access for research laboratory or clinic facilities. LED-mediated PDT applications have shown promising results for the treatment of different types of disease. However, few studies have determined the effects of LED-based PDT on cancer cells. For the first time, the aim of this study was to explore the therapeutic effects of 5-aminolevulinic acid (5-ALA)-mediated PDT after LED irradiation on two sub-types (a poorly aggressive MCF-7 and a highly aggressive MDA-MB-231) of breast cancer cell lines. The effectiveness of 5-ALA PDT treatment was evaluated by WST-1, annexin V, and acridine orange staining with different energy levels. The LED system was specially developed with optical power and wavelength stability techniques. The system consists of user interface and embedded LED controller with real-time optic power output calibration by photodiode feedback. Our results demonstrated that the cell viability of breast cancer cells was considerably decreased a LED dose-dependent manner (P < 0.05). Additionally, a significant increase in the percentage of apoptotic cells was detected in breast cancer cells after irradiation with LED at a density of 18 and 30 J/cm2 energy. Consequently, the LED system could be effectively used for irradiation of 5-ALA in the treatment of breast cancer cells.

Optimization of 5-aminolevulinic acid-based photodynamic therapy protocol for breast cancer cells.

BACKGROUND: Photodynamic therapy (PDT) is a therapeutic strategy for the treatment of cancer. 5-aminolevulinic acid (5-ALA) as a precursor of the protoporphyrin IX (PpIX) has a great potential for PDT application. Although 5-ALA-based PDT has been studied in many pre-clinical and clinical studies for breast cancer, there are different PDT application protocols in the literature. Therefore, the aim of this study was to determine the optimal in vitro protocol for 5-ALA-based PDT in breast cancer treatment. METHODS: The therapeutic effects of 5-ALA (1 and 2.5 mM) on two different subtypes of breast cancer cell line (MCF-7 and MDA-MB-231) were evaluated by PpIX-fluorescence accumulation and WST-1 analysis. Then, the cells were irradiated with diode laser at different doses (1.5, 3, 6, 9 and 12 J/cm2). After irradiation, the anticancer effects of 5-ALA were analyzed through cell viability and cell death analysis. RESULTS: Our results showed that 5-ALA exhibited a higher PpIX fluorescence in both breast cancer cells for 4 h incubation. After irradiation, 1 mM 5-ALA significantly reduced the proliferation of breast cancer cells in a laser dose-dependent manner and induced apoptotic cell death upon 24 h incubation (p < 0.05). However, MDA-MB-231 cells were more sensitive to 5-ALA-based PDT than MCF-7 cells in a dose of 9 J/cm2 and 12 J/cm2. CONCLUSION: Our preliminary findings proposed an optimal in vitro protocol of 5-ALA-based PDT by using a laser diode for breast cancer. However, there is a need to investigate the underlying molecular mechanisms of 5-ALA/PDT sensitivity among the subtypes of breast cancer.