Anticancer Activity of the Acetylenic Derivative of Betulin Phosphate Involves Induction of Necrotic-Like Death in Breast Cancer Cells In Vitro

Abstract

Betulin (BT) is a natural pentacyclic lupane-type triterpene exhibiting anticancer activity. Betulin derivatives bearing propynoyloxy and phosphate groups were prepared in an effort to improve the availability and efficacy of the drug. In this study, a comparative assessment of the in vitro anticancer activity of betulin and its four derivatives was carried out using two human breast cancer cell lines: SK-BR-3 and MCF-7. In both studied cell lines, 30-diethoxyphosphoryl-28-propynoylbetulin (compound 4) turned out to be the most powerful inhibitor of growth and inducer of cellular death. Detailed examination of that derivative pertained to the mechanisms underlying its anticancer action. Treatment with compound 4 decreased DNA synthesis and up-regulated p21WAF1/Cip1 mRNA and protein levels in both cell lines. On the other hand, that derivative caused a significant increase in cell death, as evidenced by increased lactate dehydrogenase (LDH) release and ethidium homodimer uptake. Shortly after the compound addition, an increased generation of reactive oxygen species and loss of mitochondrial membrane potential were detected. The activation of caspase-3 and fragmentation of genomic DNA suggested an apoptotic type of cell death. However, analysis of cellular morphology did not reveal any nuclear features typical of apoptosis. Despite necrosis-like morphology, dead cells exhibited activation of the cascade of caspases. These observations have led to the conclusion that compound 4 pushed cells to undergo a form of necrotic-like regulated cell demise.

Correlation between the composition of PLA-based folate targeted micelles and release of phosphonate derivative of betulin

“…Studies on endometrial adenocarcinoma and melanoma cell lines revealed activation of caspase-3 dependent apoptosis after treatment with 28-O-propynoylbetulin [36][37][38]. However, the MCF7 breast cancer cell line turned out to be highly resistant to that compound [39]. As continuation of the compound development, we inserted the diethoxyphosphoryl group at C29 position of the acetylenic derivative of betulin.…”

The Influence of Betulin and Its Derivatives EB5 and ECH147 on the Antioxidant Status of Human Renal Proximal Tubule Epithelial Cells

“…The structures of the synthesized compounds were determined based on their 1 H- 13 C-and 31 P-NMR (Bruker AVANCE III HD 600, Billerica, MA, USA, deuterated chloroform), IR (IRAffinity-1 FTIR spectrometer; Shimadzu Corporation, Kyoto, Japan, KBr pellet), and MS spectra (Bruker Impact II, Billerica, MA, USA). MThe melting point, R f parameters, and spectroscopic ( 1 H, 13 C, and 31 P NMR) data for the tested compounds were consistent with the literature information [10,44]. (The most important data characterizing compounds EB5 and ECH147 are presented in Table S2, Supplementary Materials).…”

Immunogenic ferroptosis and where to find it?

“…On the other hand, the main morphological changes in apoptosis are chromatin condensation and blebbing, together with cell shrinkage and nuclear fragmentation. 17–19 Ferroptosis is also morphologically different from necroptosis, which is characterized by swelling of the cells and intracellular organelles, and membrane rupture. 18 20 21 …”

“…On the other hand, the main morphological changes in apoptosis are chromatin condensation and blebbing, together with cell shrinkage and nuclear fragmentation. [17][18][19] Ferroptosis is also morphologically Open access Open access different from necroptosis, which is characterized by swelling of the cells and intracellular organelles, and membrane rupture. 18 20 21 It was recently shown in human trophoblast cells (primary PHT cells and the BeWo human trophoblast cell line) that macroblebbing of the membrane occurred during ferroptosis.…”