The retinoblastoma (RB) gene encodes the retinoblastoma pocket protein, which controls the cell cycle by binding to unphosphorylated E2F transcription factors and inhibiting their activation. The function of BRCA1 and the anti-apoptotic protein Bcl-2 in lung cancer, however, is still debated. Objective:The purpose of this research is to look at the relationship between the cell-cycle proteins BRCA1, BCL2, and RB and lung cancer etiology and progression. Experimental Design: Cases from major hospitals and many private histopathological laboratories between 2018 and 2021 were reviewed for immunohistochemical expression of BRCA1, BCL2, and RB. A total of 60 people (20 healthy people as a control group and 40 patients with lung carcinoma) were reviewed and analyzed for immunohistochemical expression of these genes. Results: In (90.0%) of cases, RB-IHC was overexpressed, according to the data. The BRCA1 overexpression was seen in (95.0 %). Though BCL2 was overexpressed in (92.5%) of the cases. When comparing the healthy and lung cancer groups, there is a highly significant difference at (P<0.01). Conclusion: Overexpression of RB, BRCA1, and BCL2 in lung cancers with little or no regulatory role may suggest mutational events, which act in collaboration with numerous other genetic mutations in these tissues. The study findings indicate that disruption of cell cycle proteins may perform a unique function in lung cancer disease onset and development and suggest that all patients have abnormalities in the BRCA1, BCL2, and RB proteins. have a role in lung carcinomas.