Inhibitory role of AMP‑activated protein kinase in necroptosis of HCT116 colon cancer cells with p53 null mutation under nutrient starvation

Abstract

Simultaneous induction of other types of programmed cell death, alongside apoptosis, in cancer cells may be considered an attractive strategy for the development of more effective anticancer therapies. The present study aimed to investigate the role of AMP-activated protein kinase (AMPK) in nutrient/serum starvation-induced necroptosis, which is a programmed form of necrosis, in the presence or absence of p53. The present study detected higher cell proliferation and lower cell death rates in the HCT116 human colon cancer cell line containing a p53 null mutation (HCT116 p53 -/-) compared with in HCT116 cells harboring wild-type p53 (HCT116 p53 +/+ ), as determined using a cell viability assay. Notably, western blot analysis revealed a relatively lower level of necroptosis in HCT116 p53 -/cells compared with in HCT116 p53 +/+ cells. Investigating the mechanism, it was revealed that necroptosis may be induced in HCT116 p53 +/+ cells by significantly increasing reactive oxygen species (ROS) and decreasing mitochondrial membrane potential (MMP), whereas little alterations were detected in HCT116 p53 -/cells. Unexpectedly, a much lower level of ATP was detected in HCT116 p53 -/cells compared with in HCT116 p53 +/+ cells. Accordingly, AMPK phosphorylation on the Thr172 residue was markedly increased in HCT116 p53 -/cells. Furthermore, western blot analysis and ROS measurements indicated that AMPK inhibition, using dorsomorphin dihydrochloride, accelerated necroptosis by increasing ROS generation in HCT116 p53 -/cells. However, AMPK activation by AICAR did not suppress necroptosis in HCT116 p53 +/+ cells. In conclusion, these data strongly suggested that AMPK activation may be enhanced in HCT116 p53 -/cells under serum-depleted conditions via a drop in cellular ATP levels. In addition, activated AMPK may be at least partially responsible for the inhibition of necroptosis in HCT116 p53 -/cells, but not in HCT116 p53 +/+ cells.

AMP‐kinase inhibitor dorsomorphin reduces the proliferation and migration behavior of colorectal cancer cells by targeting the AKT/mTOR pathway

“…Our data indicated that dorsomorphin decreased the levels of p‐AKT, p‐70s6k, and cyclin D1. In line with our data, another recent study showed that inhibition of AMPK, by dorsomorphin, accelerated necroptosis by increasing the level of ROS in HCT116 p53−/− cells …”

Dysregulated Phosphorylation of p53, Autophagy and Stemness Attributes the Mutant p53 Harboring Colon Cancer Cells Impaired Sensitivity to Oxaliplatin

“…In the case of cancers, cells bearing wild-type TP53 gene expressing functional p53 protein is regarded to be a strong tumor suppressor while, mutated TP53 gene expressing a mutant p53 protein with GOF tactically overcomes the cell death pathways and make cells resistant to chemotherapeutic drug treatments ( 41 , 42 ). The p53 mutations being one of the most frequently occurring mutations in colon cancer with its proven role in inducing resistance to therapeutic drugs, the mutant p53 marks itself as a prominent predictive molecular marker for chemoresistance ( 43 – 45 ).…”

“…Many studies have described the role of autophagy in tumor chemoresistance as context-dependent ( 42 ) suggesting that wild-type p53 induces autophagy ( 81 ), whereas mutant p53 represses ( 82 , 83 ) it. However, studies depicting autophagy as a cytoprotective mechanism of chemoresistance in colon cancer cells being linked their p53 status are limited or nearly nil.…”

Novel Carbazole-Piperazine Hybrid Small Molecule Induces Apoptosis by Targeting BCL-2 and Inhibits Tumor Progression in Lung Adenocarcinoma In Vitro and Xenograft Mice Model

“…The mixed cells were loaded onto EVE TM slides (Nano-EnTek-Inc.). To investigate the number of total cells, live-cells and dead-cells followed a previous study [61]. Cell cytotoxicity percentage was calculated by using percentage formula for live-cells in the treated group versus live cells in control group in different concentration of ECPU-0001 (0, 1, 2, 3 and 4 μM ECPU-0001 and DMSO) after culturing in complete media (CM).…”