Effects of repurposed drug candidates nitroxoline and nelfinavir as single agents or in combination with erlotinib in pancreatic cancer cells

Abstract

BackgroundPancreatic cancer (PC) is the fourth most common cause of cancer death. Combination therapies with classical chemotherapeutic agents improved treatment of advanced PC at the cost of a relevant toxicity, but the 5-year survival rate remains below 5%. Consequently, new therapeutic options for this disease are urgently needed. In this study, we explored the effect of two repurposed drug candidates nelfinavir and nitroxoline, approved for non-anticancer human use, in PC cell lines. Nelfinavir and nitroxoline were tested as single agents, or in combinations with or without erlotinib, a targeted drug approved for PC treatment.MethodsThe effects of the drugs on the viability of AsPC-1, Capan-2 and BxPC-3 PC cell lines were assessed by MTT. The impact of the treatments on cell cycle distribution and apoptosis was analyzed by flow cytometry. The effects of treatments on proteins relevant in cell cycle regulation and apoptosis were evaluated by western blot. Self-renewal capacity of PC cell lines after drug treatments was assessed using a clonogenic assay.ResultsWhen used as single agents, nelfinavir and nitroxoline decreased viability, affected cell cycle and reduced the expression of relevant cell cycle proteins. The effects on apoptosis were variable among PC cell lines. Moreover, these agents drastically impaired clonogenic activity of the three PC cell lines. Combinations of nelfinavir and nitroxoline, with or without erlotinib, resulted in dose- and cell-dependent synergistic effects on cell viability. These effects were paralleled by cell cycle alterations and more consistent apoptosis induction as compared to single agents. Treatments with drug combinations induced drastic impairment of clonogenic activity in the three cell lines.ConclusionsThis study shows that two non-antitumor drugs, nelfinavir and nitroxoline, as single agents or in combination have antitumor effects that appear comparable, or in some case more pronounced than those of erlotinib in three PC cell lines. Our results support repurposing of these approved drugs as single agents or in combination for PC treatment.Electronic supplementary materialThe online version of this article (10.1186/s13046-018-0904-2) contains supplementary material, which is available to authorized users.

Bridelia speciosa Müll.Arg. Stem bark Extracts as a Potential Biomedicine: From Tropical Western Africa to the Pharmacy Shelf

“…Briefly, the HepG2 cells were seeded in 96-well plates (5 × 103 cells/well) and they were treated the following day for 24, 48, or 72 hours with B. speciosa methanol and water extracts at various concentrations as indicated, or with vehicle (control). The MTT assay was performed as previously described [26]. The IC 50 values were calculated while using the CompuSyn software.…”

Nitroxoline: repurposing its antimicrobial to antitumor application

“…It affected the cell cycle distribution, reducing the expression of the proteins cyclin D3 and cyclin B1 involved in the cell cycle. It also impaired the clonogenic activity of all three cell lines (Veschi et al, 2018). Its effect on the cell cycle following nitroxoline treatment was more evident at higher concentrations (40 µM) (Veschi et al, 2018).…”

“…Nitroxoline was recently shown to be an effective antitumor agent in both pancreatic and small-cell lung cancers (SCLC) (Veschi et al, 2018;Yu et al, 2019). In both cases, it impaired cell viability (Veschi et al, 2018;Yu et al, 2019), decreasing that of pancreatic cell lines AsPC-1, Capan-2 and BxPC-3. It affected the cell cycle distribution, reducing the expression of the proteins cyclin D3 and cyclin B1 involved in the cell cycle.…”

“…It also impaired the clonogenic activity of all three cell lines (Veschi et al, 2018). Its effect on the cell cycle following nitroxoline treatment was more evident at higher concentrations (40 µM) (Veschi et al, 2018). Its antitumor ability was further improved when nitroxoline was used in combination with nelfinavir (Veschi et al, 2018), a competitive inhibitor of HIV aspartyl protease, and, in combination with other antiretroviral drugs, in treating HIV infection (Moyle et al, 1998).…”

“…Its antitumor ability was further improved when nitroxoline was used in combination with nelfinavir (Veschi et al, 2018), a competitive inhibitor of HIV aspartyl protease, and, in combination with other antiretroviral drugs, in treating HIV infection (Moyle et al, 1998). Concurrent treatment with both compounds resulted in a dose-and cell-dependent synergistic effect on cell viability, an effect on the cell cycle and on the induction of apoptosis, further impairing the clonogenic activity of pancreatic cell lines (Veschi et al, 2018).…”