Thymoquinone (TQ) has been shown to exhibit antitumor properties. Thymoquinone-loaded nanostructured lipid carrier (TQ-NLC) was developed to improve the bioavailability and cytotoxicity of TQ. This study was conducted to determine the cytotoxic effects of TQ-NLC on breast cancer (MDA-MB-231 and MCF-7) and cervical cancer cell lines (HeLa and SiHa). TQ-NLC was prepared by applying the hot high pressure homogenization technique. The mean particle size of TQ-NLC was 35.66 ± 0.1235 nm with a narrow polydispersity index (PDI) lower than 0.25. The zeta potential of TQ-NLC was greater than −30 mV. Polysorbate 80 helps to increase the stability of TQ-NLC. Differential scanning calorimetry showed that TQ-NLC has a melting point of 56.73°C, which is lower than that of the bulk material. The encapsulation efficiency of TQ in TQ-NLC was 97.63 ± 0.1798% as determined by HPLC analysis. TQ-NLC exhibited antiproliferative activity towards all the cell lines in a dose-dependent manner which was most cytotoxic towards MDA-MB-231 cells. Cell shrinkage was noted following treatment of MDA-MB-231 cells with TQ-NLC with an increase of apoptotic cell population (P < 0.05). TQ-NLC also induced cell cycle arrest. TQ-NLC was most cytotoxic towards MDA-MB-231 cells. It induced apoptosis and cell cycle arrest in the cells.

This investigation evaluated the antileukemia properties of a zerumbone (ZER)-loaded nanostructured lipid carrier (NLC) prepared by hot high-pressure homogenization techniques in an acute human lymphoblastic leukemia (Jurkat) cell line in vitro. The apoptogenic effect of the ZER-NLC on Jurkat cells was determined by fluorescent and electron microscopy, Annexin V-fluorescein isothiocyanate, Tdt-mediated dUTP nick-end labeling assay, cell cycle analysis, and caspase activity. An MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) assay showed that ZER-NLC did not have adverse effects on normal human peripheral blood mononuclear cells. ZER-NLC arrested the Jurkat cells at G2/M phase with inactivation of cyclin B1 protein. The study also showed that the antiproliferative effect of ZER-NLC on Jurkat cells is through the intrinsic apoptotic pathway via activation of caspase-3 and caspase-9, release of cytochrome c from the mitochondria into the cytosol, and subsequent cleavage of poly (adenosine diphosphate-ribose) polymerase (PARP). These findings show that the ZER-NLC is a potentially useful treatment for acute lymphoblastic leukemia in humans.

A new therapeutic approach of looking at the expression of glucose-regulated protein (GRP) 58 as an indication of cisplatin sensitivity may eradicate fruitless treatment and side effects in patients with cervical cancer. Thymoquinone, the bioactive compound in Nigella sativa, has been reported to have an antiproliferative effect on cervical cancer cells. This study compared the cytotoxic effects of cisplatin, a drug commonly used in the treatment of cervical cancer, and thymoquinone in cervical cancer (HeLa and SiHa) cell lines by 3-(4,5-Dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and measured GRP58 expression in the cells by quantitative real-time polymerase chain reaction and Western blotting. Cisplatin had higher antiproliferative activity towards the cervical cancer cell lines than thymoquinone in a dose-dependent and time-dependent manner. However, cisplatin was more toxic to normal 3T3 and Vero cell lines than thymoquinone. The half maximal inhibitory concentration (IC50) of cisplatin in HeLa and SiHa cells at 72 hours was 13.3±2.52 μM and 19.5±2.12 μM, respectively. Meanwhile, the IC50 of thymoquinone in HeLa and SiHa cells was 29.57±5.81 μM and 23.41±1.51 μM, respectively (P<0.05). A significant correlation was found between the cytotoxicity of cisplatin and expression of GRP58, but this relationship was not significant for thymoquinone. Therefore, the response of cervical cancer cells to cisplatin can be predicted on the basis of GRP58 expression.

Ethyl acetate and dichloromethane extract of Dillenia suffruticosa (EADS and DCMDS, respectively) can be a potential anticancer agent. The effects of EADS and DCMDS on the growth of HeLa cervical cancer cells and the expression of apoptotic-related proteins had been investigated in vitro. Cytotoxicity of the extracts toward the cells was determined by 5-diphenyltetrazolium bromide assay, the effects on cell cycle progression and the mode of cell death were analyzed by flow cytometry technique, while the effects on apoptotic-related genes and proteins were evaluated by quantitative real-time polymerase chain reaction, and Western blot and enzyme-linked immunosorbent assay, respectively. Treatment with DCMDS inhibited (P < 0.05) proliferation and induced apoptosis in HeLa cells. The expression of cyclin B1 was downregulated that led to G2/M arrest in the cells after treatment with DCMDA. In summary, DCMDS induced apoptosis in HeLa cells via endoplasmic reticulum stress-induced apoptotic pathway and dysregulation of mitochondria. The data suggest the potential application of DCMDS in the treatment of cervical cancer.