Printing a cure: A tailored solution for localized drug delivery in liver cancer treatment.

Adjuvant chemotherapy is highly recommended for liver cancer to enhance survival rates due to its tendency to recur frequently. Localized drug-eluting implants have gained traction as an alternative to overcome the limitations of systemic chemotherapy. This work describes the development of biodegradable 3D printed (3DP) bilayer films loaded with 5-fluorouracil (5FU) and cisplatin (Cis) with different infill percentages where the 5FU layers were 40%, 30%, and 30% and Cis layers were 10%, 15%, and 10% for films A, B, and C, respectively. The relevant characterization tests were performed, and the drug content of films was 0.68, 0.50, and 0.50 mg of 5FU and 0.39, 0.80, and 0.34 mg of Cis for films A, B, and C, respectively. Cis release was affected by the alterations to the film design, where films A, B, and C showed complete release at 12, 14, and 23 days, respectively. However, 5FU was released over 24 h for all films. The films were stable for up to two weeks after storage at 25 °C/65% relative humidity and four weeks at 4 °C where drug content, tensile strength, FTIR, and thermal analysis results demonstrated negligible alterations. The cytotoxicity of the films was assessed by MTS assays using HepG2 cell lines demonstrating up to 81% reduction in cell viability compared to blank films. Moreover, apoptosis was confirmed by Western Blots and the determination of mitochondrial cell potential, highlighting the potential of these films as a promising approach in adjuvant chemotherapy.

Hormetic effects of curcumin on oxidative stress injury induced by trivalent arsenic in isolated rat hepatocytes.

Objective: Arsenic (As) poisoning is a worldwide public health problem. Arsenic can cause cancer, diabetes, hepatic problems, etc. Hence, we investigated possible hepatoprotective properties of curcumin against As3+-induced liver damages in freshly isolated rat hepatocytes. Materials and Methods: Isolation of hepatocytes was done by the two-step liver perfusion method using collagenase. The EC50 concentration of As3+ was used in toxicity assessments and curcumin (2, 5, and 10 µM) was added 15 min before As3+ addition to isolated hepatocytes. Curcumin impact was assessed in terms of cytotoxicity, lipid peroxidation induction, reactive oxygen species (ROS) levels, and mitochondrial membrane potential. Results: As3+ significantly increased cytotoxicity, malondialdehyde and ROS levels and induced mitochondrial membrane damage and hepatocyte membrane lysis after 3 hr incubation. Curcumin 2 µM significantly prevented lipid peroxidation induction, ROS formation, and mitochondrial membrane damage; while curcumin 5 µM had no apparent effect on these parameters, curcumin 10 µM potentiated them. Conclusion: Curcumin only at low doses could ameliorate oxidative stress injury induced by As3+ in isolated rat hepatocytes.

Characterisation of cytochrome P450 isoenzyme activity in sheep liver and placental microsomes.

INTRODUCTION: Drug metabolism during pregnancy is a complex process that involves maternal, placental and fetal sites of metabolism. Indeed, there is a lack of clarity provided from drug metabolism in human pregnancy due to ethical limitations. Large animal models of human pregnancy provide an opportunity to quantify activity of phase 1 drug metabolism mediated by cytochrome P450 (CYP) enzymes in the maternal, placental, and fetal compartments. Herein, we have validated a comprehensive assay to quantify maternal, placental, and fetal CYP activity. METHODS: Isolated microsomes from sheep maternal liver, placenta, and fetal liver (140d gestation, term = 150d) were incubated with CYP-specific probe drugs to quantify the activity of CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A. Inhibition studies were performed to validate specificity of probe drugs. The validated assay was developed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: CYP1A2, CYP2B6, CYP2C8, CYP2C19, CYP2D6, CYP2E1 and CYP3A were active in maternal liver. In contrast, only CYP1A2, CYP2C8 and CYP2D6 were active in the placenta, whereas CYP2B6, CYP2C8 and CYP2D6 were active in the fetal liver. Of the placental-specific CYPs validated, CYP1A2 increased in type A compared with type D placentomes, whereas CYP2C8 activity increased in type B compared with type A and C. DISCUSSION: This study has established conditions for compartment-specific CYP activity in the sheep maternal-placental-fetal unit using a validated and standardised experimental workflow. Compartment- and placentome type-specific CYP activity are important considerations when examining drug metabolism in the maternal-placental-fetal unit and in determining the impact of pregnancy complications.

Design, Synthesis and Cytotoxicity Evaluationof New 1,2-diaryl-4, 5, 6, 7-Tetrahydro-1H-benzo[d] Imidazolesas Tubulin Inhibitors.

A new series of 1,2-diaryl-4,5,6,7-tetrahydro-1H-benzo[d]imidazoles, possessing trimethoxyphenyl pharmacophore, were synthesized to evaluate their biological activities as tubulin inhibitors. Cytotoxic activity of the synthesized compounds 7a-f was assessed against several human cancer cell lines, including MCF-7 (breast cancer cell), HEPG2 (liver hepatocellular cells), A549 (adenocarcinomic human alveolar basal epithelial cells), T47D (Human ductal breast epithelial tumor cell line) and fibroblast. According to our results, HEPG2 seems to be the most sensitive, while MCF7 was the most resistant cell line to the compounds. All the compounds expect 7b, possessed satisfactory activity against HEPG2 with mean IC50 values ranging from 15.60 to 43.81 µM.

Synthesis and Molecular-cellular Mechanistic Study of Pyridine Derivative of Dacarbazine.

Dacarbazine is an antitumor prodrug which is used for the treatment of malignant metastatic melanoma and Hodgkin's disease. It requires initial activation in liver through an N-demethylationreaction. The active metabolite prevents the progress of disease via alkylation of guanine bases in DNA strands. In order to investigate the importance of imidazole ring and its dynamictautomerization in anticancer activity of dacarbazine, a pyridine analog of this drug was synthesized and the cytotoxic activity and cellular-molecular mechanisms of action for this compound were compared with those of dacarbazine. EC50 values for dacarbazine and the pyridine analog were found to be 56 µM and 33 µM respectively. Both dacarbazine and the pyridine analog resulted in formation of reactive oxygen species (ROS) upon their addition to the isolated rat hepatocytes. They also decreased the mitochondrial membrane potential and causedlysosomal membrane rupture. Cytotoxicity was prevented by ROS scavengers and antioxidants. Cytotoxicity wasalso prevented by CYP450 inhibitors, lysosomalinactivators and MPT (Mitochondrial Permeability Transition Pore) blockers.

Biological reactive intermediates that mediate dacarbazine cytotoxicity.

PURPOSE: In the following, the cellular and molecular mechanism of cytotoxicity induced by prodrug dacarbazine toward the isolated rat hepatocytes was studied. METHOD: Accelerated cytotoxicity screening technique (ACMS) was used to perform this study. RESULT: Addition of dacarbazine to isolated rat hepatocytes resulted in reactive oxygen species (ROS) formation, and lysosomal membrane leakiness before hepatocyte lysis occurred. Hepatocyte ROS generation was inhibited by desferoxamine (a ferric chelator). Cytotoxicity was prevented by antioxidants or ROS scavengers (mannitol or dimethylsulfoxide), cytochorome P450 inhibitors (phenylimidazole, diphenyliodonium chloride, 4-methylpyrazole, and benzylimidazole). In addition to lysosomal damage, dacarbazine caused hepatocyte protease activation and cell proteolysis. CONCLUSION: Dacarbazine cytotoxicity is associated with ROS (H(2)O(2), O(2)(*-) ) generation. It is suggested that H(2)O(2) could cross the lysosomal membrane, react with lysosomal Fe(2+) to form hydroxyl radical (Haber-Weiss reaction) which is the major cause of lysosomal membrane leakiness, proteases, and other digestive enzymes' release and finally the cell death.