Virginia Research Day 2022

Graduate Student Research Biomedical

Dalal Dawud, BPharm 1 ; Sanna Rahman, OMS II 1 ; Alexander S. Hernandez, OMS II 1 , Kevin McLane, OMS II 1 ; Kasia Michalak, MSc. 1 ; David J. Stephen, DO 2 Zakaria Y. Abd Elmageed, PhD 1 Corresponding author: dawuddr@warhawks.ulm.edu 08 Novel Transmembrane And Tetratricopeptide Repeat Containing-4 Protein As A Prospective Marker In Breast Cancer

Department of Biomedical Sciences 1 and Pathology 2 , VCOM Louisiana

Background: Approximately 12.9% of women will be diagnosed with breast cancer (BC) at some point during their lifetime. Although remarkable efforts have been undertaken for treatment of BC patients, treatment of aggressive tumors are still a challenge. Therefore, further studies are needed to discover accurate biomarkers and elucidate the underlying molecular mechanisms of BC metastasis. Thus, we aimed to determine the expression and function of transmembrane and tetratricopeptide repeat containing-4 (TMTC4) in BC tissues and correlate it with clinical outcomes. Methods: The expression of TMTC4 in BC cells was determined by Western blot analysis. Furthermore, immunohistochemical staining of TMTC4 was performed on paraffin embedded sections of 192 BC and normal cases. The

immunohistochemical score (HS) of TMTC4 was correlated with clinical outcomes of BC patients. Results: The results demonstrated that TMTC4 was significantly high (p<0.0001) in BC tissues (n=160) compared to normal and adjacent normal tissues (n=32). There was no difference in the protein expression between lobular and ductal BC tissues. Furthermore, public data showed high protein expression of TMTC4 was correlated (p<0.0001) to low relapse-free survival (RFS) (25.2-month survival) compared to longer RFS in BC patients who are expressing low TMTC4 (43-month survival). Conclusion: TMTC4 was overexpressed in BC cells and tissues compared to normal controls. This protein can be used as a potential diagnostic biomarker and had a strong positive correlation with survival status.

Thus, identifying TMTC4 signaling pathway holds promise for the development of targeted therapies for BC patients.

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2 0 2 2 R e s e a r c h R e c o g n i t i o n D a y