Fatty-monastrol derivatives and its cytotoxic effect against melanoma cell growth

C-phycocyanin decreases proliferation and migration of melanoma cells: In silico and in vitro evidences

The incidence and number of deaths caused by melanoma have been increasing in recent years, and the pigment C-phycocyanin (C-PC) appears as a possible alternative to treat this disease. So, the objective of this study was to combine in silico and in vitro analysis to understand the main anti-melanoma pathways exerted by C-PC. We evaluated the ability of C-PC to bind to the main cellular targets related in the progression of melanoma through molecular docking, and the reflection of this bind in the biological effects in the B16F10 cell line through in vitro analysis. Our results showed that C-PC was able to bind BRAF and MEK, which are related to the signal transduction pathway for proliferation and survival. There was also an interaction between C-PC and cyclin-dependent kinase 4 and 6. In vitro analysis demonstrated that C-PC decreased B16F10 cell proliferation, as observed by cell viability and mitotic index assays. C-PC also interacted with matrix metalloproteinase 2 and 9 and N-cadherin, which may have caused the decrease in cell migration observed in vitro. Besides that, C-PC interacts with VEGF, a factor responsible for regulating the proliferation and cellular invasion pathways. Finally, C-PC did not alter the cell viability of the non-tumoral melanocytes. Therefore, C-PC is a strong anti-tumor candidate for the treatment of melanoma, since it acts in different cellular pathways of melanoma, without causing damage to non-tumoral cells.

Synthesis of pyrazoline fatty chain derivatives and its effects on melanoma cells

Skin cancer is the most common type of cancer in Brazil, representing 30% of all cases. Among these, melanoma represents only 3% of malignant neoplasms; however, it is the most serious and has a high capacity for metastasis. For this reason, it is extremely important to identify more efficient compounds and treatments that stop or decrease the proliferation of melanoma, even in its more advanced stages. This work reports the synthesis and biological evaluation of two homologous series of pyrazoline fatty chain derivatives as potent antitumoral agents in the melanoma B16F10 cell line. Cells were treated with pyrazoline fatty chain compounds (3, 30, 300, and 3000 μM) for 0, 24, 48, and 72 h. Decreased cell viability was observed when using most compounds at different concentrations and times. The structure-activity relationship (SAR) between antitumoral activity and the number of carbons and lipophilicity, as well as the oxygen-sulfur bioisosteric exchange, was evaluated. Among the tested derivatives, the lipophilic compounds 5-hydroxy-5-(trifluoromethyl)-3-undecyl-4,5-dihydro-1H-pyrazole-1-carboxamide (2d) and 5-hydroxy-5-(trifluoromethyl)-3-undecyl-4,5-dihydro-1H-pyrazole-1-thiocarboxamide (3d) showed the best results in the B16F10 cell line, as they produced the best cell viability decrease effects. The presence of fatty unbranched undecyl chain in the molecular structure appears to be important for its antimelanoma properties.

Evaluation of the antioxidant activities of fatty polyhydroquinolines synthesized by Hantzsch multicomponent reactions

Polyhydroquinolines (PHQs) are the unsymmetrical Hantzsch derivatives of 1,4-dihydropyridines with several biological applications. In this work, new fatty 2- and 3-substituted PHQ derivatives from different fatty acids and fatty alcohol feedstocks were synthesized at good yields via a four-component reaction (4CR). The antioxidant activities of fatty PHQs were investigated using three different antioxidant methods. The experiments showed that the compounds derived from 2-nitrobenzaldehyde and fatty palmitic (C16:0) and oleic (C18:1) chains showed better antioxidant activity. This revealed that combining the ortho NO2 group in the aromatic ring with the insertion of fatty chains in the PHQ core contributed to the antioxidant activity. However, among all the fatty PHQs tested, the fatty 2-substituted compound derived from oleyl alcohol and 2-nitrobenzaldehyde showed the highest antioxidant activity (EC50, 2.11-4.69 μM), which was similar to those of the antioxidant standards butylated hydroxytoluene (EC50, 1.98-6.47 μM) and vitamin E (EC50, 1.19-5.88 μM). In addition, this lipophilic compound showed higher antioxidant activity than the antihypertensive drug nifedipine (EC50, 49.25-126.86 μM). These results indicate that the new fatty PHQs may find novel applications as antioxidant additives.

Novel pyrimidinic selenourea induces DNA damage, cell cycle arrest, and apoptosis in human breast carcinoma

Novel pyrimidinic selenoureas were synthesized and evaluated against tumour and normal cell lines. Among these, the compound named 3j initially showed relevant cytotoxicity and selectivity for tumour cells. Three analogues of 3j were designed and synthesized keeping in view the structural requirements of this compound. Almost all the tested compounds displayed considerable cytotoxicity. However, 8a, one of the 3j analogues, was shown to be highly selective and cytotoxic, especially for breast carcinoma cells (MCF-7) (IC₅₀ = 3.9 μM). Furthermore, 8a caused DNA damage, inhibited cell proliferation, was able to arrest cell cycle in S phase, and induced cell death by apoptosis in human breast carcinoma cells. Moreover, predictions of pharmacokinetic properties showed that 8a may present good absorption and permeation characteristics for oral administration. Overall, the current study established 8a as a potential drug prototype to be employed as a DNA interactive cytotoxic agent for the treatment of breast cancer.