Identification of CENP-B as a novel candidate therapeutic target in acute Myeloid Leukaemia

Halawi, Maryam 2025. Identification of CENP-B as a novel candidate therapeutic target in acute Myeloid Leukaemia. PhD Thesis, Cardiff University. Item availability restricted.

	PDF - Accepted Post-Print Version Restricted to Repository staff only until 8 March 2027 due to copyright restrictions. Download (11MB)
	PDF (Cardiff University Electronic Publication Form) - Supplemental Material Restricted to Repository staff only Download (177kB)

Abstract

Despite advances in treatment, many patients with acute myeloid leukaemia (AML)have poor outcomes, particularly for older adults. Targeted therapeutic drugs offer the best chance of improving these outcomes. Designing targeted treatments requires an understanding of the molecular mechanisms driving the growth and survival of AML blasts. Here, I identify abnormally expressed proteins in AML using mass spectrometry. The proteomic profile of AML patient samples (FAB types M0/M1, M2, and M4/M5; n=91) was compared to normal haemopoietic stem and progenitor cells (CD34+ cells; n=5). Out of 4,888 detected proteins, the expression of 956 proteins significantly differed between AML and control samples (p <0.05). Amongst the most frequently overexpressed proteins I identified centromere protein B. CENPB was significantly upregulated in (83% (76/91) of AML samples compared to normal CD34+ controls (20% (1/5), with an average 2.2-fold overexpression (p=5x10-7). CENP-B plays a role in the functioning of centromeres, which accurately segregate chromosomes during cell division. Furthermore, CENP-B upregulation has been linked to carcinogenesis and tumour development in various malignancies. Western blot analysis of 19 AML patient samples and 3 CD34+ samples validated this finding showing upregulation of CENP-B and a correlation with mass spectrometry results. Further, a western blot survey of six AML cell lines (NOMO1, MV4-11, OCI-AML2, THP1, U937, PLB985) all showed CENP-B expression. To establish its role in proliferation and survival of AML cells, I carried out a knockdown of CENP-B for three cell lines (OCI-AML2, THP1, PLB985) using two different shRNA constructs. CENP-B expression was reduced by >80% when compared to control. This led to decreased proliferation (50%-67%, p <0.0001), while viability remained unaffected. Conversely, while overexpression of CENP-B in AML cell lines (2-fold) was tolerated, overexpression of CENP-B in primary CD34+ cells markedly reduced viability inducing a >3-fold increase in the frequency of apoptotic cells suggesting that constitutive expression is lethal in normal cells. In summary, I have identified >956 significant mis-regulated proteins in AML and have shown that the overexpression of one of these, the centromere protein CENP-B. is important to maintain optimal proliferation in AML cells. Since overexpression of CENP-B was not tolerated by normal cells, increased levels of CENP-B are unlikely to initiate the development of leukaemia, and this change more likely occurs at a later stage in leukaemogenesis where it plays a role in promoting AML proliferation.

Item Type:	Thesis (PhD)
Date Type:	Completion
Status:	Unpublished
Schools:	Schools > Medicine
Date of First Compliant Deposit:	9 March 2026
Last Modified:	16 Mar 2026 13:48
URI:	https://orca.cardiff.ac.uk/id/eprint/185618

Actions (repository staff only)

Edit Item