Acetylcholine and Prolactin, Other Factors in Breast Cancer

Acetylcholine (ACh) and prolactin (PRL) are increasingly recognized as additional factors potentially influencing breast cancer biology. Their effects may depend on tumor-cell context and on the molecular signaling state of individual breast cancer subtypes. This study aimed to evaluate phosphorylation responses to ACh and PRL and examine transcriptomic associations involving related signaling genes. MCF7, T47D, and MDA-MB-231 breast cancer cell lines were treated with ACh, PRL, or combined ACh + PRL for 4 h. Significant changes in selected phosphoproteins were summarized for proteins related to AKT-S6 kinase, EGFR-ERK, TP53-Src/PLC-γ1, and STAT3-JUN signaling. Transcriptomic analyses evaluated associations between acetylcholinesterase (ACHE) or prolactin receptor (PRLR) expression and selected signaling-related genes in breast cancer cohorts, including subtype-specific analyses, tumor-versus-normal comparisons, and overall-survival associations. ACh and PRL produced distinct, cell-line-specific phosphorylation patterns. The MCF7 cell line showed increased AKT, p70S6K, and p53 phosphorylation after ACh, whereas combined treatment increased AKT and STAT3 phosphorylation. The T47D cell line showed a mixed response, with combined treatment increasing p70S6K, PLC-γ1, and Src phosphorylation but reducing AKT, ERK1/2, and c-Jun phosphorylation. The MDA-MB-231 cell line showed the broadest response, with combined ACh + PRL increasing AKT, RSK, STAT3, and c-Jun phosphorylation. Transcriptomic analyses identified subtype-dependent associations of ACHE and PRLR with genes encoding AKT, S6 kinase, ERK, Src/PLC-γ1, STAT3, and JUN-related proteins. Several genes also showed differential tumor-versus-normal expression or survival associations. ACh and PRL are associated with context-dependent signaling responses in breast cancer. Experimental phosphoprotein changes and tumor transcriptomic associations converged on related signaling modules but represented different molecular levels and did not establish complete pathway activation or direct causality. These findings support further investigation of ACh-PRL interactions and their potential contribution to breast cancer biology.