HOXA1 Contributes to Bronchial Epithelial Cell Cycle Progression by Regulating p21/CDKN1A

Area of Science:

• Pulmonary Medicine
• Cell Biology
• Developmental Biology

Background:

• Airway basal cells are stem cells responsible for airway epithelium regeneration after injury.
• Reduced homeobox (HOX) A1 expression is observed in airway stem cells from chronic obstructive pulmonary disease patients.
• The role of HOXA1 in airway epithelial cell proliferation and migration remains largely unknown.

Purpose of the Study:

• To investigate the function of HOXA1 in bronchial epithelial cell proliferation and migration.
• To elucidate the molecular mechanisms by which HOXA1 influences airway epithelial repair.

Main Methods:

• Generated a HOXA1 knockout bronchial epithelial cell line using CRISPR/Cas9 technology.
• Assessed cell proliferation using spheroid formation assays.
• Evaluated cell migration using scratch assays.
• Performed single-cell RNA sequencing and flow cytometry for cell cycle analysis.

Main Results:

• HOXA1 knockout cells exhibited reduced proliferation, forming smaller spheroids compared to wild-type cells.
• HOXA1 knockout cells showed delayed migration in scratch assays.
• Single-cell RNA sequencing revealed downregulation of cell cycle progression genes in HOXA1 knockout cells.
• Flow cytometry indicated G0/G1 phase cell cycle arrest in HOXA1 knockout cells, associated with decreased Cyclin E1 and increased p21/CDKN1A expression.

Conclusions:

• HOXA1 plays a significant role in promoting bronchial epithelial cell proliferation and migration.
• HOXA1 may regulate cell cycle progression through the p21/CDKN1A pathway in airway epithelial cells.
• These findings suggest HOXA1 as a potential therapeutic target for enhancing airway epithelial repair.