A small molecular agent YL529 inhibits VEGF-D-induced lymphangiogenesis and metastasis in preclinical tumor models in addition to its known antitumor activities

Study of the anticancer effect of new quinazolinone hydrazine derivatives as receptor tyrosine kinase inhibitors

The advent of novel receptor tyrosine kinase inhibitors has provided an important therapeutic tool for cancer patients. In this study, a series of quinazolinone hydrazide triazole derivatives were designed and synthesized as novel MET (c-MET) receptor tyrosine kinase inhibitors. The antiproliferative effect of the synthesized compounds was examined against EBC-1, A549, HT-29 and U-87MG cells by MTT assay. MET kinase inhibitory effect was tested by a Homogenous Time Resolved Fluorescence (HTRF) assay. The antiproliferative effect of compounds in a three-dimensional spheroid culture was studied by acid phosphatase (APH) assay, while apoptosis induction was examined by Hoechst 33258 staining. We found that compound CM9 bearing p-bromo benzyl pendant inhibited MET kinase activity at the concentrations of 10-50 μM (% Inhibition = 37.1-66.3%). Compound CM9 showed antiproliferative effect against cancer cells, in particular lung cancer cells with MET amplification (EBC-1) with an IC50 value of 8.6 μM. Moreover, this derivative inhibited cell growth in spheroid cultures in a dose-dependent manner and induced apoptosis in cancer cells. Assessment of inhibitory effect of CM9 against a panel of 18 different protein kinases demonstrated that this compound also inhibits ALK, AXL, FGFR1, FLT1 (VEGFR1) and FLT4 (VEGFR3) more than 50% at 25 μM. Finally, molecular docking and dynamics simulation corroborated the experimental findings and showed critical structural features for the interactions between CM9 and target kinases. The findings of this study present quinazolinone hydrazide triazole derivatives as kinase inhibitors with considerable anticancer effects.

Prognosis and targeting of pre-metastatic niche

As the main cause of tumoral fatality, metastasis remains to be one of the most urgent difficulties researcher struggled to overcome. During the development and progression of metastasis, the establishment of pre-metastatic niche is crucial in preparing fertile microenvironment for disseminated tumor cells settlement and colonization in distant metastatic target sites. The key participators, including the primary tumor-derived factors, bone marrow-derived cells, stromal cells of both the host and the potential metastatic sites, regulate the temporal progress of potential metastasis. Firstly, pioneers are sent from primary tumor, recruiting immunosuppressive cells; then circulating tumor cells settled and colonized; and finally, micrometastases develop. Here, we summarize the therapeutic strategies presented in recent years targeting different stages of the pre-metastatic niche formation and discuss their chances and challenges in clinical translation, providing promising approaches for metastasis prevention and therapeutic interventions.

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.

Chloroquine potentiates the anticancer effect of sunitinib on renal cell carcinoma by inhibiting autophagy and inducing apoptosis

Sunitinib based adjuvant chemotherapy combined with chloroquine (CQ) for the treatment of renal cell carcinoma (RCC) is in clinical trials; however, its anti-RCC effect and the mechanism remain unclear. In the present study, the anti-RCC effect of sunitinib with CQ and the underlying mechanism was investigated. An MTT assay demonstrated that CQ enhanced the proliferation inhibitory effect of sunitinib against the OS-RC-2 RCC cell line. CQ inhibited sunitinib-induced autophagy in OS-RC-2, which was evidenced by the inhibition of autophagic vacuoles, acidic vesicular organelle formation, light chain 3 (LC3)-II recruitment to the autophagosomes and the conversion of LC3-I to LC3-II, as induced by sunitinib. The inhibition of autophagy by CQ enhanced sunitinib-induced apoptosis, which was characterized by the activation of caspase-3, caspase-9, Bcl-2 and p53. Additionally, the exposure of OS-RC-2 cells to CQ and sunitinib resulted in the inhibition of AKT, tuberous sclerosis complex 2, mechanistic target of rapamycin and p70 ribosomal S6 kinase, which are associated with cell proliferation. In in vivo study, a combination of sunitinib with CQ in mice significantly reduced OS-RC-2 cell xenograft growth compared with the sunitinib alone group. In conclusion, the present study demonstrated that CQ may enhance the anti-RCC effect of sunitinib by inhibiting the autophagy induced by sunitinib, and enhance the rate of apoptosis. Inhibiting cell proliferation may also serve a role in the synergistic antitumor effect of sunitinib and CQ. These data suggest that combination therapy of sunitinib with CQ may be a promising strategy for adjuvant chemotherapy in RCC.

#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.