Are Smokers Switching to Vaping at Lower Risk for Cancer? (Electronic Cigarettes and Cancer Risk)

Are Smokers Switching to Vaping at Lower Risk for Cancer?

This project will address a growing public health concern, namely, the health risks or benefits of e-cig use relative to cigarette smoking. The investigators will use biomarkers of early effects of relevance to cancer to determine the carcinogenic potential of e-cig use relative to cigarette smoking in oral epithelium, which is a target tissue for smoking-associated cancer. The study population will consist of one group of smokers who are interested in switching to e-cig use (Grp 1), one group of smokers who do not intend to change their smoking habits (Grp 2), and one group of non-users who would like to maintain their nonsmoking non-vaping status (Grp 3); The total number of participants in this project is 150 (n = 50, each group). The investigators will use an integrative 'multi-omics' approach complemented with single-locus/gene validation analyses to detect temporal changes in the genome, epigenome, and transcriptome relevant to cancer in the oral cells of the participants as the intervention progresses.

Study Overview

• Status: Active, not recruiting
• Conditions: Cigarette Smoking
• Intervention / Treatment: Device: NIDA Standard Research E-cigarette (SREC)

Detailed Description

Electronic cigarettes (e-cig) are increasingly popular among adult smokers and adolescent never smokers. Chemical analyses of e-cig vapor and liquid have shown the presence of many of the same carcinogens as those found in cigarette smoke, albeit in generally lower concentrations. However, the carcinogenic potential of e-cig has not been investigated in e-cig users (otherwise known as 'vapers'). The investigators will investigate the cancer-causing potential of e-cig use as compared to cigarette smoking by quantifying molecular changes linked to risk of cancer in smokers who switch to e-cig use vs. those who maintain their smoking habits. Leveraging a source population for ongoing studies on e-cig, the investigators will recruit smokers who are interested in switching to e-cig use, and two control groups of non-vapers, including smokers and nonsmokers who do not intend to change their smoking and nonsmoking status, respectively (n = 50, each group). Smokers consenting to switch completely to e-cig will be assigned to a 3-month intervention with a standard e-cig with fully described product characteristics. Control groups will maintain their smoking/nonsmoking habits during the intervention. At weekly intervals, the investigators will verify participants' compliance through personal interviews, CO breath tests, cotinine quantification, and vaping/smoking topography measurements. The investigators will use a non-invasive brushing technique to collect oral cells from the inside of the cheeks of all participants at baseline and every 2 weeks, afterwards. The investigators will use an integrative 'multi-omics' approach complemented with single-locus/gene validation analyses to detect temporal changes in the genome, epigenome, and transcriptome relevant to cancer in the oral cells of the participants as the intervention progresses.

• Study Type: Interventional
• Enrollment (Estimated): 150
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90033
      • University of Southern California, Health Sciences Campus

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 22 years to 55 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Being male or female between the ages of 22-55;
• Being able to read and write in English and understand and give informed consent;
• Giving consent to strictly follow the study protocol throughout the study;
• Not planning to move, take an extended vacation, or undergo surgery during the study;
• Reporting smoking of > 5 manufactured cigarettes per day for at least 1 year (applicable to participants who will undergo intervention with e-cig (Grp 1) or continue to smoke (Grp 2) only); and
• Presenting with an expired air CO measurement of > 7 parts per million (ppm) at baseline (applicable to participants who will undergo intervention with e-cig (Grp 1) or continue to smoke (Grp 2) only).

Exclusion Criteria:

• Having oral infection/inflammation, gum disease, dental decay, immune system disorders, diabetes, respiratory diseases (e.g., asthma), or kidney diseases;
• Having any unstable or significant medical condition (e.g., symptomatic heart conditions) in the past 12 months ;
• Having body mass index < 18 kg/m2 or > 40 kg/m2
• Being pregnant or having a baby in the past 12 months;
• Having uncontrolled mental illness or substance abuse (e.g., alcoholism) or inpatient treatment for those conditions in the past 12 months;
• Having used recreational or illicit drugs in the past 3 months;
• Having used any medication known to induce/inhibit CYP450 2A6 enzyme;
• Having any known allergy to propylene glycol/vegetable glycerin (applicable participants who will undergo intervention with e-cig (Grp 1) only); and
• Having another member of household participating in the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Vapers; Smokers will switch to NIDA Standard Research E-cigarette (SREC).	Device: NIDA Standard Research E-cigarette (SREC); Smokers will switch to NIDA Standard Research E-cigarette (SREC).
No Intervention: Smokers; Smokers will continue to smoke.
No Intervention: Nonsmokers non-vapers; Control nonsmokers non-vapers will continue to refrain from smoking or vaping.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Genetic changes	Number and location of DNA damage	3 months
Epigenetic changes	Number of epigenetic marks	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gene expression	Relative gene expression	Every 2 weeks for 3 months
DNA methylation	Pattern and distribution of aberrant DNA methylation	Every 2 weeks for 3 months
Histone modifications	Pattern and distribution of histone marks	Every 2 weeks for 3 months
Mutation	Frequency and location of mutations	Every 2 weeks for 3 months

Collaborators and Investigators

• Sponsor: University of Southern California
• Collaborators: University of California
• Investigators: Principal Investigator: Ahmad Besaratinia, University of Southern California

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2021
• Primary Completion (Estimated): July 31, 2028
• Study Completion (Estimated): July 31, 2028

Study Registration Dates

• First Submitted: November 16, 2018
• First Submitted That Met QC Criteria: November 21, 2018
• First Posted (Actual): November 23, 2018

Study Record Updates

• Last Update Posted (Actual): August 6, 2025
• Last Update Submitted That Met QC Criteria: August 1, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: Electronic Nicotine Delivery System
• Other Study ID Numbers: HS-18-00744

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: There is no plan to make individual participant data (IPD) available to other researchers.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes