Novel Pathways and Mechanism of Nicotine-Induced Oral Carcinogenesis

Misconceptions About E-cigarettes Among Healthcare Workers at Primary Health Care Centers in Riyadh, Saudi Arabia

BACKGROUND

As e-cigarettes become increasingly popular, especially among youth, addressing the misinformation surrounding their use is crucial. This study aims to enhance healthcare workers' knowledge of the risks associated with e-cigarettes, ultimately improving patient education and public health outcomes.

AIMS AND OBJECTIVES

To assess health workers' awareness of misconceptions surrounding e-cigarette use and the implications of this awareness on their personal use and professional practices  Methods: A cross-sectional study was conducted at the primary healthcare centers of Prince Sultan Military Medical City (PSMMC) in Riyadh, Saudi Arabia, to assess healthcare professionals' awareness of e-cigarette misconceptions. Utilizing a convenience sampling technique, the target sample size was 246 participants, and the actual participants were 208, ensuring robust representation. Eligible participants include PSMMC healthcare providers currently working in PHC settings, while those from other departments or institutions will be excluded. Data was collected through a structured online questionnaire covering demographic information, personal e-cigarette usage, awareness of health impacts, addictive potential, and regulations related to e-cigarettes.

RESULTS

The study included a total of 208 participants, with the majority (150 participants, 72.1%) aged between 25 and 35 years. The group was predominantly male (108 participants, 51.9%) and Saudi nationals (147 participants, 70.7%). Additionally, 108 participants (51.9%) were married, and half were specializing in family medicine. While only 35 (16.8%) personally use e-cigarettes, 124 (59.6%) know someone who does, and social media is the primary information source for 127 (61.06%) participants. A strong majority (185,88.9%) believe e-cigarettes are harmful, and 164 (78.8%) recognize the potential harm to bystanders from e-cigarette aerosol. The views on e-cigarettes being less harmful than traditional cigarettes are mixed, with 64 (30.8%) in agreement, while 136 (65.4%) acknowledge their addictive nature. There is widespread support for regulating e-cigarettes like tobacco products (150, 72.1%) and prohibiting their use for individuals under 18 (164, 78.8%). Statistical analysis shows a significant association between the specialty of family medicine and the belief in the health risks of e-cigarettes (p=0.029), indicating the need for targeted education and policy measures.

CONCLUSION

Despite participants' relatively good knowledge of e-cigarettes and their health implications, a significant number of misconceptions persist. This highlights the need for ongoing education and training programs tailored for healthcare professionals to address gaps in understanding and ensure they are equipped with accurate information.

Decoding Oral Carcinogenesis and Tumor Progression in Whole Cigarette Smoke Exposure: A Systematic Review

This systematic review aims to highlight the molecular mechanisms by which whole cigarette smoke affects oral carcinogenesis and its progression in human oral cells, based on evidence from original research articles published in the literature. A literature search was conducted using three databases: Web of Science, Scopus, and PubMed from May to June 2024. The articles were screened, and the data were extracted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines (2020). The included studies were subsequently evaluated using the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) tool for bias factors. From the 14 included studies, two types of cell lines were frequently utilized: human oral mucosal epithelial cells or oral squamous cell carcinoma cells. In these cell lines, one of three forms of exposure was applied: cigarette smoke, its extract, or condensate. The mechanism of oral carcinogenesis and tumor progression includes aberrations in the heme metabolic pathway, modulation of miRNA-145, NOD1 and BiP expression, MMP-2, MMP-9, and cathepsin modulation, abnormal TSPO binding, RIP2-mediated NF-κB activation, MZF1-mediated VEGF binding, and activation of the RAGE signaling pathway. In conclusion, cigarette smoke significantly influences the development and progression of oral squamous cell carcinoma, based on the evidence highlighted in human oral cells. While previous studies have focused on specific carcinogens and pathways, this review added to our understanding of the overall impact of whole cigarette smoke on oral carcinogenesis at the molecular and cellular levels.

α5-nAChR/ADAM10 signaling mediates nicotine-related cutaneous melanoma progression via STAT3 activation

Skin cutaneous melanoma (SKCM) is the skin malignancy with the highest mortality rate, and its morbidity rate is on the rise worldwide. Smoking is an independent marker of poor prognosis in melanoma. The α5-nicotinic acetylcholine receptor (α5-nAChR), one of the receptors for nicotine, is involved in the proliferation, migration and invasion of SKCM cells. Nicotine has been reported to promote the expression of a disintegrin and metalloproteinase 10 (ADAM10), which is the key gene involved in melanoma progression. Here, we explored the link between α5-nAChR and ADAM10 in nicotine-associated cutaneous melanoma. α5-nAChR expression was correlated with ADAM10 expression and lower survival in SKCM. α5-nAChR mediated nicotine-induced ADAM10 expression via STAT3. The α5-nAChR/ADAM10 signaling axis was involved in the stemness and migration of SKCM cells. Furthermore, α5-nAChR expression was associated with ADAM10 expression, EMT marker expression and stemness marker expression in nicotine-related mice homograft tissues. These results suggest the role of the α5-nAChR/ADAM10 signaling pathway in nicotine-induced melanoma progression.

Cell signaling and epigenetic regulation of nicotine-induced carcinogenesis

Nicotine, a naturally occurring tobacco alkaloid responsible for tobacco addiction, has long been considered non-carcinogenic. However, emerging evidence suggests that nicotine may possess carcinogenic properties in mice and could be a potential carcinogen in humans. This review aims to summarize the potential molecular mechanisms underlying nicotine-induced carcinogenesis, with a specific focus on epigenetic regulation and the activation of nicotinic acetylcholine receptors (nAChRs) in addition to genotoxicity and excess reactive oxygen species (ROS). Additionally, we explore a novel hypothesis regarding nicotine's carcinogenicity involving the downregulation of stem-loop binding protein (SLBP), a critical regulator of canonical histone mRNA, and the polyadenylation of canonical histone mRNA. By shedding light on these mechanisms, this review underscores the need for further research to elucidate the carcinogenic potential of nicotine and its implications for human health.

Downregulation of FHL2 suppressed trophoblast migration, invasion and epithelial-mesenchymal transition in recurrent miscarriage

RESEARCH QUESTION

Is four and a half LIM domain 2 (FHL2) involved in trophoblast migration, invasion and epithelial-mesenchymal transition (EMT) in recurrent miscarriage?

DESIGN

Villus tissue was collected from 24 patients who had experienced recurrent miscarriage and 24 healthy controls. FHL2 mRNA and protein expression in villus specimens were observed by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Small interfering RNA and overexpression plasmid were used to change the FHL2 expression. JAR and HTR8/SVneo cell lines were used to conduct scratch-wound assay and transwell assay to detect trophoblast migration and invasion of FHL2. Downstream molecule expression of mRNA and protein and EMT markers were verified by qRT-PCR and Western blot.

RESULTS

Significantly lower FHL2 mRNA (P = 0.019) and protein (P = 0.0014) expression was found in trophoblasts from the recurrent miscarriage group compared with healthy controls. FHL2 knockdown repressed migration (P = 0.0046), invasion (P < 0.001) and EMT, as shown by significant differences in mRNA and protein expression of the EMT markers N-cadherin, E-cadherin, Vimentin and Snail (all P < 0.05) of extravillus trophoblasts. FHL2 overexpression enhanced migration (P = 0.025), invasion (P < 0.001) and EMT of extravillus trophoblasts (all EMT markers P < 0.05). The positive upstream factor FHL2 in the extracellular signal-related kinase pathway induced JunD expression, thereby promoting trophoblast migration and invasion via matrix metalloproteinase 2.

CONCLUSIONS

FHL2 is involved in a regulatory pathway of trophoblast migration, invasion and EMT during early pregnancy, and may have a role in recurrent miscarriage pathogenesis, which can serve as a possible target for novel therapeutic development.

Prevalence, Knowledge, and Attitudes among Health Professions Students toward the Use of Electronic Cigarettes

Healthcare professionals are standing against the widespread use of e-cigarettes among the population, especially young adults. E-cigarettes are generally introduced, especially via social media platforms, as a safer alternative to conventional cigarette smoking. The aim of this study was to measure the prevalence of e-cigarette use among healthcare professions students at the University of Jordan, as well as to explore their knowledge and attitudes toward the use of e-cigarettes. An anonymous Google-Form®-based cross-sectional questionnaire was presented to potential participants at the University of Jordan. Students' responses were analyzed using SPSS® 23.0 software. A total of 679 online surveys were completed. About 37.4% of students reported using e-cigarettes at least once in their lifetime and about 20% of students were current e-cigarette users. The multivariate analysis showed that the factors associated with E-cigarette smoking are being male, having mothers, siblings, or friends using e-cigarettes, having easy access to e-cigarettes, and having social media as the main source of knowledge regarding e-cigarettes. The relatively high acceptance level and use of e-cigarettes among health professions students should be an alarming sign to decision-makers to give more attention to legislation that controls tobacco products including e-cigarette selling and advertising.

Inflammation and Invasion in Oral Squamous Cell Carcinoma Cells Exposed to Electronic Cigarette Vapor Extract

Electronic cigarettes (eCig) represent a new avenue of tobacco exposure that involves heating oil-based liquids and the delivery of aerosolized flavors with or without nicotine, yet little is known about their overall health impact. The oral cavity is an anatomic gateway for exposure that can be compromised by activating myriad of signaling networks. Oral squamous cell carcinoma (OSSC) is a common malignancy affecting 30,000 people in the United States each year. Our objective was to determine the impact of eCig and nicotine on gingival OSSC invasion and their secretion of pro-inflammatory molecules. Gingiva-derived Ca9-22 cells and tongue-derived Cal27 cells were exposed to eCig vapor extract (EVE) generated from Red Hot or Green Apple (Apple) flavored eCig solution +/- nicotine for 6 hours. Isolation of protein lysates and collection conditioned media was done after treatment. Real-time cellular invasion was assessed using a RTCA DP instrument. Protein expression was determined using western blot. Compared to controls, we observed: elevated NF-kB, TNF-α, ERK, JNK, MMP-13 and cell invasion by Ca9-22 treated with Apple EVE; increased TNF-α and JNK by Ca9-22 treated with Red Hot EVE; and increased TNF-α and JNK by Cal27 cells treated with both Apple and Red Hot EVE. We conclude that eCig flavoring and nicotine orchestrated differential cell invasion and inflammatory effects. This study provides an important initial step in dissecting mechanisms of cancerous invasion and molecular avenues employed by OSCC.

Identification and validation of a cigarette smoke-related five-gene signature as a prognostic biomarker in kidney renal clear cell carcinoma

Cigarette smoking greatly promotes the progression of kidney renal clear cell carcinoma (KIRC), however, the underlying molecular events has not been fully established. In this study, RCC cells were exposed to the tobacco specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, nicotine-derived nitrosamine) for 120 days (40 passages), and then the soft agar colony formation, wound healing and transwell assays were used to explore characteristics of RCC cells. RNA-seq was used to explore differentially expressed genes. We found that NNK promoted RCC cell growth and migration in a dose-dependent manner, and RNA-seq explored 14 differentially expressed genes. In TCGA-KIRC cohort, Lasso regression and multivariate COX regression models screened and constructed a five-gene signature containing ANKRD1, CYB5A, ECHDC3, MT1E, and AKT1S1. This novel gene signature significantly associated with TNM stage, invasion depth, metastasis, and tumor grade. Moreover, when compared with individual genes, the gene signature contained a higher hazard ratio and therefore had a more powerful value for the prognosis of KIRC. A nomogram was also developed based on clinical features and the gene signature, which showed good application. Finally, AKT1S1, the most crucial component of the gene signature, was significantly induced after NNK exposure and its related AKT/mTOR signaling pathway was dramatically activated. Our findings supported that NNK exposure would promote the KIRC progression, and the novel cigarette smoke-related five-gene signature might serve as a highly efficient biomarker to identify progression of KIRC patients, AKT1S1 might play an important role in cigarette smoke exposure-induced KIRC progression.