Upregulation of wild-type p53 by small molecule-induced elevation of NQO1 in non-small cell lung cancer cells

Dissecting the pleiotropic roles of reactive oxygen species (ROS) in lung cancer: From carcinogenesis toward therapy

Lung cancer is a major cause of morbidity and mortality. The specific pulmonary structure to directly connect with ambient air makes it more susceptible to damage from airborne toxins. External oxidative stimuli and endogenous reactive oxygen species (ROS) play a crucial role in promoting lung carcinogenesis and development. The biological properties of higher ROS levels in tumor cells than in normal cells make them more sensitive and vulnerable to ROS injury. Therefore, the strategy of targeting ROS has been proposed for cancer therapy for decades. However, it is embarrassing that countless attempts at ROS-based therapies have had very limited success, and no FDA approval in the anticancer list was mechanistically based on ROS manipulation. Even compared with the untargetable proteins, such as transcription factors, ROS are more difficult to be targeted due to their chemical properties. Thus, the pleiotropic roles of ROS provide therapeutic potential for anticancer drug discovery, while a better dissection of the mechanistic action and signaling pathways is a prerequisite for future breakthroughs. This review discusses the critical roles of ROS in cancer carcinogenesis, ROS-inspired signaling pathways, and ROS-based treatment, exemplified by lung cancer. In particular, an eight considerations rule is proposed for ROS-targeting strategies and drug design and development.

Pyrogallol promotes growth arrest by activating the p53-mediated up-regulation of p21 and p62/SQSTM1-dependent degradation of β-catenin in nonsmall cell lung cancer cells

Pyrogallol (1,2,3-trihydroxybenzene), a polyphenolic natural compound, has attracted considerable attention with regard to its potential anticancer activity. However, further study is needed to elucidate the underlying mechanism related to the antiNSCLC activity of pyrogallol and provide a comprehensive theoretical basis for better clinical utilization of pyrogallol. Our current study aims to investigate the effects and potential underlying mechanisms of pyrogallol on the inhibition of NSCLC growth. Our results showed that pyrogallol treatment induced cell cycle arrest at the G2/M phase and apoptosis in two different NSCLC cell lines. Mechanistically, we found that the induction of cell cycle arrest in NSCLC cells at the G2/M phase by pyrogallol was due to the upregulation of p21 in a p53-dependent manner. And blockade of p53 and p21 effectively abolished the cell cycle arrest at the G2/M phase. Meanwhile, p53 inhibition has been found to abrogate the pyrogallol-induced apoptosis of the two NSCLC cells. Moreover, we revealed that the inhibitory effects of pyrogallol on β-catenin signaling resulted from autophagy initiation depending on p53 activation, accompanied by an increase in p62/SQSTM1 expression, thus p62 subsequently interacting with ubiquitinated β-catenin and facilitating autophagic destruction of β-catenin. Furthermore, in vivo experiments demonstrated that pyrogallol exerted growth inhibition on NSCLC with low toxicity through the same molecular mechanism as observed in vitro. Our findings could contribute to the understanding of the mechanism by which pyrogallol negatively regulates NSCLC growth, which could be effective in treating NSCLC.

Effect of IFN‑γ encapsulated liposomes on major signal transduction pathways in the lymphocytes of patients with lung cancer

Globally, lung cancer affected 2.2 million individuals and caused 1.8 million deaths in 2021. Lung cancer is caused by smoking, genetics and other factors. IFN-γ has anticancer activity. However, the mechanism by which IFN-γ has an effect on lung cancer is not fully understood. The present study aimed to assess the effect of IFN-γ on the peripheral lymphocytes of patients with lung cancer compared with healthy controls. The efficacy of IFN-γ against oxidative stress was assessed using a comet repair assay and the effects of IFN-γ on p53, PARP1 and OGG1 genes and protein levels in lymphocytes was evaluated by RT-qPCR and western blotting. DNA damage was significantly reduced in the lymphocytes of patients treated with IFN-γ. However, there was no effect in the cells of healthy individuals after treatment with naked IFN-γ [IFN-γ (N)] and liposomal IFN-γ [IFN-γ (L)]. Following treatment with IFN-γ (N) and IFN-γ (L), the p53, PARP1 and OGG1 protein and gene expression levels were significantly increased (P<0.001). It has been suggested that IFN-γ may induce p53-mediated cell cycle arrest and DNA repair in patients. These findings supported the idea that IFN-γ (N) and IFN-γ (L) may serve a significant role in the treatment of lung cancer, via cell cycle arrest of cancer cells and repair mechanisms.