Orbitides isolated from flaxseed induce apoptosis against SGC-7901 adenocarcinoma cells

Area of Science:

• Biochemistry
• Molecular Biology
• Pharmacology

Background:

• Plant-derived cyclic peptides, particularly orbitides, show promise for anticancer therapies.
• Flax (Linum usitatissimum L.) is a source of unique bioactive compounds.
• Understanding the mechanisms of these compounds against cancer cells is crucial.

Purpose of the Study:

• To investigate the anticancer effects of flaxseed orbitides on SGC-7901 cancer cells.
• To elucidate the underlying molecular mechanism of cell death induced by these orbitides.
• To compare the efficacy of flaxseed orbitides with specific pure orbitides.

Main Methods:

• Treatment of SGC-7901 cancer cells with flaxseed orbitides.
• Assessment of apoptosis through nuclear morphology and DNA fragmentation.
• Analysis of mitochondrial apoptosis pathway proteins, including cytochrome C, caspases, and PARP.
• Evaluation of the Bax/Bcl-2 ratio.

Main Results:

• Flaxseed orbitides induced apoptosis in SGC-7901 cells in a dose-dependent manner.
• Apoptosis was characterized by nuclear shrinkage and DNA fragmentation.
• Flaxseed orbitides demonstrated stronger inhibition compared to pure orbitides [1-9-NαC]-linusorb B2 and [1-9-NαC]-linusorb B3.
• The mitochondrial apoptosis pathway was activated, evidenced by cytochrome C release, caspase 9 and 3 activation, and PARP cleavage.
• The Bax/Bcl-2 ratio increased, and cleaved caspase 9 and 3 expression was elevated.

Conclusions:

• Flaxseed orbitides induce apoptosis in SGC-7901 cancer cells via the mitochondrial pathway.
• The mechanism involves cytochrome C release, caspase activation, and modulation of the Bax/Bcl-2 ratio.
• These findings highlight the potential of flaxseed orbitides as a therapeutic strategy for cancer treatment.