Raltitrexed induces mitochondrial-mediated apoptosis in SGC7901 human gastric cancer cells

Abstract

Abstract. Raltitrexed is a specific inhibitor of thymidylate synthase (TS), which has been considered as a potential chemotherapeutic agent for the treatment of advanced gastric cancer. In the present study, the apoptosis mechanisms of raltitrexed in SGC7901 human gastric cancer cells were investigated. The cytotoxic activity of raltitrexed on SGC7901 cells was determined by cell counting kit-8 (CCK-8) assay. The CCK-8 assay indicated that raltitrexed inhibits SGC7901 cell growth in a dose-and time-dependent manner. The morphological changes were observed by fluorescent microscopy, and characteristic morphological changes, including nuclear shrinkage and apoptotic bodies, were observed following Hoechst 33258 staining. The effects on apoptosis, cell cycle, mitochondrial transmembrane potential and reactive oxygen species (ROS) were measured by flow cytometry. The analysis revealed that raltitrexed exerted a growth inhibitory effect by inducing time-dependent apoptosis and cell-cycle arrest at the G 0 /G 1 phase. In addition, a compromised mitochondrial membrane potential and overproduction of ROS demonstrated the involvement of the mitochondrial signaling pathway. Raltitrexed-induced caspase-3-dependent apoptosis was identified using a caspase-3 activity assay and pretreatment with the caspase-3 inhibitor, Ac-DEVD-CHO (sequence, Ac-Asp-Glu-Val-Asp-CHO). The activity of caspase-3 was analyzed with a spectrometer. The protein expression levels of Bax, Bcl-2, cytochrome c, cleaved caspase-3 and TS were examined by western blot and the mRNA expression level of TS was detected by quantitative polymerase chain reaction. The analysis revealed that the protein levels of Bax, cytochrome c and cleaved caspase-3 were significantly increased by raltitrexed, while Bcl-2 expression levels were reduced. Furthermore, raltitrexed increased the expression of the TS protein and mRNA in a time-dependent manner. These results indicate that raltitrexed induces the apoptosis of SGC7901 cells through the caspase-3-dependent mitochondrial signaling pathway and upregulates the expression of the TS protein and mRNA.

Effect of evodiamine on the proliferation and apoptosis of A549 human lung cancer cells

“…Previous studies have indicated that evodiamine may stimulate the production of ROS to induce apoptosis by causing mitochondrial damage (27,28). The present study found that following treatment with evodiamine, the anti-apoptotic genes Survivin and Bcl-2 in the mitochondria-associated apoptosis pathway were significantly downregulated, while the downstream caspase-3 and caspase-8 activity was significantly upregulated, indicating that the mitochondrial pathway is important for evodiamine-induced apoptosis.…”

Raltitrexed plus oxaliplatin-based transarterial chemoembolization in patients with unresectable hepatocellular carcinoma

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15‑hydroxy‑6α,12‑epoxy‑7β,10αH,11βH‑spiroax‑4‑ene‑12‑one exerts anti‑tumor effects against osteosarcoma through apoptosis induction

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