The impact of chronic exposure to cigarette and waterpipe smoke extracts on telomeres, telomerase, and cancer progression.

Chronic exposure to cigarette and waterpipe smoke extracts causes telomere shortening and increases telomerase activity, promoting cancer progression in lung, colon, and breast cancer cells.

• Why it matters: Understanding how tobacco smoke influences telomere dynamics is crucial because telomere dysfunction is linked to genomic instability and cancer development, yet the direct effects of whole-smoke exposure remain underexplored.
• What they did: Researchers exposed lung (A549), colon (HCT116), and breast (MCF7) cancer cell lines to sub-toxic concentrations of cigarette and waterpipe smoke extracts for 12 weeks, then measured telomere length, telomerase activity, EMT markers, and cell migration.
• The result: Findings showed waterpipe smoke shortened telomeres in A549 cells, cigarette smoke increased telomerase activity, and both smoke types upregulated EMT markers and migration, indicating smoke-induced telomere disruption and cancer progression potential.