BMC Cancer (Aug 2018)

Targeting colorectal cancer cell metabolism through development of cisplatin and metformin nano-cubosomes

  • Mona M. Saber,
  • Abdulaziz M. Al-mahallawi,
  • Noha N. Nassar,
  • Björn Stork,
  • Samia A. Shouman

DOI
https://doi.org/10.1186/s12885-018-4727-5
Journal volume & issue
Vol. 18, no. 1
pp. 1 – 11

Abstract

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Abstract Background Colorectal cancer (CRC) remains a leading cause of death worldwide. Utilizing cisplatin in CRC is correlated with severe adverse effects and drug-resistance. Combined anticancer drug-treatment, along with, their enhanced delivery, can effectively kill cancer through multiple pathways. Nano-cubosomes are emerging as nanocarriers for anticancer therapies, hence, we constructed nano-cubosomes bearing cisplatin and cisplatin-metformin combination for investigation on HCT-116 cells. Methods Nano-cubosomes bearing either cisplatin alone or cisplatin-metformin combination were formulated using emulsification technique. The loaded nano-cubosomes were characterized in vitro and the optimized formulation was selected. Their cytotoxic effects were investigated by Sulphorhodamine-B (SRB) assay. The AMPK/mTOR metabolic pathway as well as the Akt/mTOR pathway were analyzed using ELISA technique. Colorimetry was used in NADPH oxidase, LDH and caspase-3 activity determination. Results nano-cubosomal formulations exhibited superior cytotoxic effect compared to unformulated cisplatin. This cytotoxic effect was profound upon incorporation of metformin, an indirect mTOR inhibitor, in cisplatin nano-cubosomes. The induced CRC cell apoptosis was through inhibition of several metabolic pathways, namely, AMPK/mTOR and Akt/mTOR. Drug-loaded nano-cubosomes ensued depletion in glucose and energy levels that led to AMPK activation and thus mTOR inhibition. mTOR was additionally inhibited via suppression of p-Akt (Ser473) levels after nano-cubosomal treatment. Moreover, drug-loaded nano-cubosomes produced a notable escalation in ROS levels, evident as an increase in NADPH oxidase, inhibition of LDH and a consequential upsurge in caspase-3. Conclusion These results demonstrated the influence exerted by cisplatin-loaded nano-cubosomes on CRC cell survival and enhancement of their cytotoxicity upon metformin addition.

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