Synergistic activity of sorafenib and betulinic acid against clonogenic activity of non‐small cell lung cancer cells

Abstract

The highly selective multi‐targeted agent sorafenib is an inhibitor of a number of intracellular signaling kinases with anti‐proliferative, anti‐angiogenic and pro‐apoptotic effects in various types of tumors, including human non‐small cell lung cancer (NSCLC). Betulin displays a broad spectrum of biological and pharmacological properties, including anticancer and chemopreventive activity. Combination of drugs with different targets is a logical approach to overcome multilevel cross‐stimulation among key signaling pathways in NSCLC progression. NSCLC cell lines, A549, H358 and A427, with different KRAS mutations, and normal human peripheral blood lymphocyte cells, were treated with sorafenib and betulinic acid alone and in combination. We examined the effect of different combined treatments on viability (MTS test), proliferation and apoptotic susceptibility based on flow cytometry, alterations in signaling pathways by western blotting and colony‐forming ability. The combination of sorafenib with betulinic acid had a strong effect on the induction of apoptosis of different NSCLC cell lines. In addition, this combination was not toxic for human peripheral blood lymphocytes. Combination treatment changed the expression of proteins involved in the mitochondrial apoptosis pathway and induced apoptotic death by caspase activation. Importantly, combination treatment with low drug concentrations tremendously reduced the colony‐forming ability of A549, H358 and A427 cells, as compared to both compounds alone. In this study, we showed that combination therapy with low concentrations of sorafenib and betulinic acid had the capacity to induce high levels of cell death and abolish clonogenic activity in some NSCLC cell lines regardless of KRAS mutations.

Sorafenib in Combination with Betulinic Acid Synergistically Induces Cell Cycle Arrest and Inhibits Clonogenic Activity in Pancreatic Ductal Adenocarcinoma Cells

“…Recently, we have shown that combination treatment with SOR and BA caused significant proliferation-inhibitory effects in NSCLC cell lines [ 6 ]. We first investigated the effects of SOR and BA on cell viability using the MTS assay to determine whether their combination can inhibit the proliferation of human PDAC cell lines with different mutational KRAS status ( Table 1 ).…”

“…Combination treatment with SOR and BA markedly decreased the colony-forming capability of PDAC cells. This treatment has been shown previously to be nontoxic for normal human peripheral blood lymphocytes [ 6 ]. It should be noted that tumor cell cloning efficiency is positively correlated with proliferation and self-renewal abilities, which may be associated with cell tumorigenesis [ 47 ].…”

“…We have previously shown that combination treatment with sorafenib (SOR) and betulinic acid (BA) inhibits proliferation, induces cell death, and reduces colony-forming ability in non-small cell lung cancer (NSCLC) cell lines with different KRAS mutations [ 6 ]. In pancreatic cancer, activating KRAS mutations occur at a frequency of 90% [ 7 ].…”

Betulin and betulinic acid: triterpenoids derivatives with a powerful biological potential

“…Favourable results were obtained by combining BA and, respectively, vincristine, 5-fluorouracil, doxorubicin, etoposide, actinomycin D, mithramycin A, cisplatin, taxol, oxaliplatin, or irinotecan, as well as ionizing radiation (Sawada et al 2004;Jung et al 2007;Gao et al 2011;Bache et al 2011;Zhao et al 2012;Csuk 2014). In turn, a combination of BE and sorafenib, a kinase inhibitor effective against various carcinomas, enhanced the induction of apoptosis in different non-small cell lung cancer lines (Kutkowska et al 2017).…”

In vitro effects of the activity of novel platinum (II) complex in canine and human cell lines

“…The assay was performed according to the method described earlier . After seeding at a density of 4 × 10 4 cells/well in a 24‐well plate (TPP, Trasadingen, Switzerland) and attaching overnight, the cells were incubated for 24 hours in medium alone or with Pt‐TCEP in the final concentration of 2 or 3 μM.…”