AUTHOR=Refaat Bassem , Zekri Jamal , Aslam Akhmed , Ahmad Jawwad , Baghdadi Mohammed A. , Meliti Abdelrazak , Idris Shakir , Sultan Sufian , Alardati Hosam , Saimeh Haitham Akram , Alsaegh Aiman , Alhadrami Mai , Hamid Tahira , Naeem Mohammed E. , Elsamany Shereef Ahmed 

TITLE=Profiling Activins and Follistatin in Colorectal Cancer According to Clinical Stage, Tumour Sidedness and Smad4 Status

JOURNAL=Pathology and Oncology Research

VOLUME=27

YEAR=2021

URL=https://www.por-journal.com/journals/pathology-and-oncology-research/articles/10.3389/pore.2021.1610032

DOI=10.3389/pore.2021.1610032

ISSN=1532-2807

ABSTRACT=<p>This study explored the roles of activins and follistatin in colorectal cancers. Paired malignant and normal colonic tissues were collected from archived paraffin-embedded (<italic>n</italic> = 90 patients) alongside fresh (<italic>n</italic> = 40 patients) specimen cohorts. Activin β-subunits, follistatin and Smad4 mRNAs and proteins were measured by real-time PCR and immunohistochemistry (IHC). Mature activin-A, -B, -AB and follistatin proteins were measured by ELISA. Cancer tissues having ≤ the 20th percentile of the Smad4 IHC score were considered as low (L-S4) group. The Smad4-intact SW480 and Smad4-null HT29 colon cancer cell lines were treated with activins and follistatin, and cell cycle was analysed by flow cytometry. The cell cycle inducing (CCND1/CCND3) and inhibitory (p21/p27) proteins alongside the survival (survivin/BCL2) and pro-apoptosis (Casp-8/Casp-3) markers were measured by immunofluorescence. Thirty-nine patients had right-sided cancers (30%) and showed higher rates of L-S4 tumours (<italic>n</italic> = 17; 13.1%) alongside worse clinicopathological characteristics relative to left-sided cancers. The βA-subunit and activin-A increased, whilst βB-subunit and activin-AB decreased, in malignant sites and the late-stage cancers revealed the greatest abnormalities. Interestingly, follistatin declined markedly in early-stage malignant tissues, whilst increased significantly in the advanced stages. All activin molecules were comparable between the early stage right- and left-sided tumours, whereas the late-stage right-sided cancers and L-S4 tumours showed more profound deregulations. <italic>In vitro</italic>, activin-A increased the numbers of the SW480 cells in sub-G1 and G0/G1-phases, whereas reduced the HT29 cell numbers in the sub-G1 phase with simultaneous increases in the G0/G1 and S phases. The p21/p27/Casp-8/Casp-3 proteins escalated, whilst CCND1/CCND3/BCL2/survivin declined in the SW480 cells following activin-A, whereas activin-A only promoted p21 and p27 alongside reduced CCND3 in the HT29 cells. By contrast, activin-AB increased the numbers of SW480 and HT29 cells in Sub-G1 and G0/G1-phases and promoted the anti-cancer and reduced the oncogenic proteins in both cell lines. In conclusion, activins and follistatin displayed stage-dependent dysregulations and were markedly altered during the advanced stages of right-sided and L-S4 cancers. Moreover, the activin-A actions in CRC could be Smad4-dependent, whereas activin-AB may act as a Smad4-independent tumour suppressor protein.</p>