YL4073 is a potent autophagy-stimulating antitumor agent in an in vivo model of Lewis lung carcinoma

Lentinan inhibited colon cancer growth by inducing endoplasmic reticulum stress-mediated autophagic cell death and apoptosis

Lentinan (SLNT) has been shown to be directly cytotoxic to cancer cells. However, this direct antitumour effect has not been thoroughly investigated in vivo, and the mechanism remains unclear. We aimed to examine the direct antitumour effect of SLNT on human colon cancer and the mechanism in vivo and in vitro. SLNT significantly inhibited tumour growth and induced autophagy and endoplasmic reticulum stress (ERS) in HT-29 cells and tumour-bearing nonobese diabetic (NOD)/severe combined immunodeficiency (SCID) mice. Experiments with the autophagy inhibitors chloroquine (CQ) and 3-methyladenine (3-MA) showed that autophagy facilitated the antitumour effect of SLNT. Moreover, ERS was identified as the common upstream regulator of SLNT-induced increases in Ca2+concentrations, autophagy and apoptosis by using ERS inhibitors. In summary, our study demonstrated that SLNT exerted direct antitumour effects on human colon cancer via ERS-mediated autophagy and apoptosis, providing a novel understanding of SLNT as an anti-colon cancer therapy.

Novel agent #2714 potently inhibits lung cancer growth by suppressing cell proliferation and by inducing apoptosis in vitro and in vivo

The use of small molecule compounds to inhibit cell proliferation is one of the most promising approaches in cancer therapy. In the present study, a cell viability assay, flow cytometry analysis, western blotting and mouse xenograft models were used to investigate the anticancer activities of #2714 and its underlying mechanisms in lung cancer. The present in vitro results suggested that #2714 significantly inhibited the viability of the human non-small cell lung cancer line SPC-A1 in a concentration- and time-dependent manner, with a half-maximal inhibitory concentration value of 5.54 µM after 48 h of treatment. Additionally, #2714 inhibited SPC-A1 cell proliferation via the Wnt/β-catenin pathway and by impairing mitochondrial membrane potential. The protein expression levels of Wnt 3a, Wnt 5a/b, phosphorylated (p)-β-catenin, p-glycogen synthase kinase 3β, and p-mitogen-activated protein kinase 14 were downregulated following treatment with #2714. Furthermore, using a mouse xenograft model, #2714 was identified to significantly inhibit tumor growth and to decrease cancer cell proliferation in vivo. #2714 may represent a novel effective anticancer compound targeting lung cancer cells. Additionally, #2714 was able to induce apoptosis and decrease cell proliferation in SPC-A1 cells via the Wnt/β-catenin pathway.

#2714, a novel active inhibitor with potent G2/M phase arrest and antitumor efficacy in preclinical models

Arresting cell cycle has been one of the most common approaches worldwide in cancer therapy. Specifically, arresting cells in the G2/M phase is a promising therapeutic approach in the battle against lung cancer. In the present study, we demonstrated the anticancer activities and possible mechanism of compound #2714, which can prompt G2/M phase arrest followed by cell apoptosis induction in Lewis lung carcinoma LL/2 cells. In vitro, #2714 significantly inhibited LL/2 cell viability in a concentration- and time-dependent manner while exhibiting few toxicities on non-cancer cells. The mechanism study showed that cell proliferation inhibition due to the treatment with #2714 correlated with G2/M phase arrest and was followed by LL/2 cell apoptosis. The characterized changes were associated with the downregulation of phosphorylated cell division cycle 25C (Cdc25C) and upregulation of p53. Apoptosis-associated activation of cleaved caspase-3 was also detected. Moreover, #2714 strongly attenuated LL/2 cell proliferation by disrupting the phosphorylation of p44/42 mitogen-activated protein kinase (MAPK). In vivo, intraperitoneal administration of #2714 (25–100 mg/kg/day) to mice bearing established tumors in xenograft models significantly prevented LL/2 tumor growth (58.1%) without detectable toxicity. Compound #2714 significantly increased apoptosis in LL/2 lung cancer cells in mice models, as observed via terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assay, and the data from an immunohistochemical analysis showed that #2714 remarkably inhibited the proliferation and angiogenesis of lung cancer in vivo. Taken together, our data suggest that #2714 has a high potential anti-lung cancer efficacy with a pathway-specific mechanism of G2/M phase arrest and subsequent apoptosis induction both in vitro and in vivo; its potential to be an anticancer candidate warrants further investigation.