RESUMO
Six ent-kaurane-type diterpenes were isolated from the roots of Isodon ternifolia. Previous studies have shown that compounds 1 and 2 exhibited cytotoxicity against three human cancer cell lines (MCF-7, A549, and HCT116), but its molecular mechanism has not been studied yet. In the present study, the inhibited proliferation of compounds 1 and 2 of two triple-negative breast cancer (TNBC) cell lines (4T1 and MDA-MB-231) have been demonstrated by MTT and colony formation assay. Flow cytometry, western blotting, and qPCR were used to further demonstrate the apoptosis process in TNBCs. Importantly, the following mitochondrial membrane potential (MMP) decrease during apoptosis was demonstrated to correlate to reactive oxygen species (ROS) production. In addition, DNA damage induced by compounds 1 and 2 was illustrated by detect of homologous recombination (HR) DNA repair genes and proteins expression, such as RAD51. These results indicated that compounds 1 and 2 could trigger the TNBCs apoptosis mediated by ROS-induced mitochondrial dysfunction and induce DNA double-strand breaks (DSBs) by down regulating HR DNA repair. Furthermore, this research reveals that the mechanism between mitochondria dysfunction and DNA damage is deserved to be investigated for elucidating the dynamic signal transduction between the nucleus and the cellular matrix during apoptosis.
Assuntos
Diterpenos do Tipo Caurano , Diterpenos , Neoplasias de Mama Triplo Negativas , Humanos , Diterpenos do Tipo Caurano/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Reparo de DNA por Recombinação , Linhagem Celular Tumoral , Diterpenos/farmacologia , Apoptose , Mitocôndrias/metabolismo , Proliferação de CélulasRESUMO
Ganoderma sinense, known as Lingzhi in China, is a medicinal fungus with anti-tumor properties. Herein, crude polysaccharides (GSB) extracted from G. sinense fruiting bodies were used to selectively inhibit triple-negative breast cancer (TNBC) cells. GSBP-2 was purified from GSB, with a molecular weight of 11.5 kDa and a composition of α-l-Fucp-(1â, ß-d-Glcp-(1â, ß-d-GlcpA-(1â, â3)-ß-d-Glcp-(1â, â3)-ß-d-GlcpA-(1â, â4)-α-d-Galp-(1â,â6)-ß-d-Manp-(1â, and â3,6)-ß-d-Glcp-(1â at a ratio of 1.0:6.3:1.7:5.5:1.5:4.3:8.0:7.9. The anti-MDA-MB-231 cell activity of GSBP-2 was determined by methyl thiazolyl tetrazolium, colony formation, scratch wound healing, and transwell migration assays. The results showed that GSBP-2 could selectively inhibit the proliferation, migration, and invasion of MDA-MB-231 cells through the regulation of genes targeting epithelial-mesenchymal transition (i.e., Snail1, ZEB1, VIM, CDH1, CDH2, and MMP9) in the MDA-MB-231 cells. Furthermore, Western blotting results indicated that GSBP-2 could restrict epithelial-mesenchymal transition by increasing E-cadherin and decreasing N-cadherin expression through the PI3K/Akt pathway. GSBP-2 also suppressed the angiogenesis of human umbilical vein endothelial cells. In conclusion, GSBP-2 could inhibit the proliferation, migration, and invasion of MDA-MB-231 cells and showed significant anti-angiogenic ability. These findings indicate that GSBP-2 is a promising therapeutic adjuvant for TNBC.
Assuntos
Movimento Celular , Ganoderma , Neoplasias de Mama Triplo Negativas , Humanos , Ganoderma/química , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Movimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Invasividade Neoplásica , Feminino , Antineoplásicos/farmacologia , Antineoplásicos/química , Transição Epitelial-Mesenquimal/efeitos dos fármacosRESUMO
Polygala tenuifolia is extensively used to treat amnesia in traditional Chinese medicine, and pharmacological studies have reported the beneficial effects of P. tenuifolia on intelligence and cognition. In the present study, the crude polysaccharide alkali-extracted from P. tenuifolia roots (PTB) inhibited lipopolysaccharide-induced microglia/astrocyte activation and significantly improved the learning and memory ability of Alzheimer's disease (AD) rats. To determine its bioactive components, a heteropolysaccharide (PTBP-1-3) was isolated from PTB. Structural analysis showed that PTBP-1-3 was composed of α-L-Araf-(1â, â3)-α-L-Araf-(1â, â5)-α-L-Araf-(1â, â3,5)-α-L-Araf-(1â, â2,5)-α-L-Araf-(1â, ß-D-Xylp-(1â, â2,3,4)-ß-D-Xylp-(1â, α-L-Rhap-(1â, ß-D-Galp-(1â, â4)-α-D-Galp-(1â, â6)-α-D-Galp-(1â, â6)-α-D-Glcp-(1â, â3,6)-α-D-Glcp-(1â, â6)-α-D-Manp-(1â, and â2,4)-ß-D-Manp-(1â residues. PTBP-1-3 decreased the production of NO, TNF-α, and IL-1ß in lipopolysaccharide-activated BV2 microglia cells in a manner similar to that of minocycline. In conclusion, PTBP-1-3 exhibited a potent inhibitory effect on neuroinflammation, and could be one of the bioactive ingredients in PTB for anti-neuroinflammation. PTB and PTBP-1-3 may be potential therapeutic agents for the treatment of AD.