Water-Pipe Smoking Exposure Deregulates a Set of Genes Associated with Human Head and Neck Cancer Development and Prognosis

Abstract

Water-pipe smoking (WPS) is becoming the most popular form of tobacco use among the youth, especially in the Middle East, replacing cigarettes rapidly and becoming a major risk of tobacco addiction worldwide. Smoke from WPS contains similar toxins as those present in cigarette smoke and is linked directly with different types of cancers including lung and head and neck (HN) carcinomas. However, the underlying molecular pathways and/or target genes responsible for the carcinogenic process are still unknown. In this study, human normal oral epithelial (HNOE) cells, NanoString PanCancer Pathways panel of 770 gene transcripts and quantitative real-time polymerase chain reaction (qRT-PCR) analysis were applied to discover differentially expressed genes (DEG) modulated by WPS. In silico analysis was performed to analyze the impact of these genes in HN cancer patient’s biology and outcome. We found that WPS can induce the epithelial–mesenchymal transition (EMT: hallmark of cancer progression) of HNOE cells. More significantly, our analysis of NanoString revealed 23 genes deregulated under the effect of WPS, responsible for the modulation of cell cycle, proliferation, migration/invasion, apoptosis, signal transduction, and inflammatory response. Further analysis was performed using qRT-PCR of HNOE WPS-exposed and unexposed cells supported the reliability of our NanoString data. Moreover, we demonstrate those DEG to be upregulated in cancer compared with normal tissue. Using the Kaplan–Meier analysis, we observed a significant association between WPS-deregulated genes and relapse-free survival/overall survival in HN cancer patients. Our findings imply that WPS can modulate EMT as well as a set of genes that are directly involved in human HN carcinogenesis, thereby affecting HN cancer patients’ survival.

Cytotoxic and Genotoxic Effects of Waterpipe on Oral Health Status

“…Three studies were in vitro 4,32,33 , and biological samples were obtained from patients in 17 studies 8,31,[33][34][35][36][37][39][40][41][42][43][44][45][46][47][48] . In addition, the levels of pro-inflammatory cytokines, the receptor activator of nuclear factor-κB (RANKL), and osteoprotegerin were evaluated [34][35][36] .…”

“…Six studies investigated the genotoxic effect of waterpipe smoke 4,32,33,[37][38][39] . A comet assay was performed in one study 33 .…”

“…A comet assay was performed in one study 33 . Cell line-based models were used to understand the mechanisms of action of waterpipe smoke on oral cells 4,32 . Immortalized nontransformed normal human oral keratinocytes (OKF6/TERT1) chronically (eight months) exposed to waterpipe smoke were developed by Patil et al 4 .…”

“…When phenotypic alterations were studied, they revealed genomic anomalies in OKF6/TERT1-waterpipe cells, with some overexpressed and some downregulated genes. In the other study that developed a cell line-based model, two human normal oral epithelial were treated with 100g/L of waterpipe smoke solution for two days 32 . When examined, both cells became more elongated and showed decreased cell-cell contact compared to untreated ones.…”

Prevalence of electronic nicotine delivery systems and waterpipe use in Brazil: where are we going?

“…As for waterpipes, studies show their association with different types of cancer [12][13][14] , given that in a one-hour session one can inhale an amount of smoke equivalent to one hundred cigarettes or more, and daily use can be equivalent to smoking ten cigarettes a day 3 .…”