Immunohistochemical Expression of β-catenin and Ki67
Protein Tumor Markers in Colorectal Adenocarcinoma among
Sudanese Patients

Ahmed H. Mohammed, Tagwa A. Mustafa, Esam M. Abd Al Raheem Al-Neelain University, Khartoum, Sudan · Nov 2, 2018

Abstract
Background: Colorectal cancer (CRC) is the third most common cancer in men and the
second most common cancer in women worldwide. Data collected in 2008 showed that
worldwide there were over 1.23 million new cases, and over 608,000 patients died from CRC
that year. Several factors influence the prognosis, including clinical, histopathological, and
biological factors related to the stage of the CRC tumor. Therefore, investigations into the
molecular mechanisms of CRC that can lead to novel biomarkers to optimize diagnosis and/or
treatment regimens are essential. Betacatenin is an intracellular protein that is an integral
component of the cadherin-mediated cell-cell interaction and a downstream transcriptional
activator in the wnt signal transduction pathway. Inappropriate activation of betacatenin has
recently been implicated in the development of colorectal carcinoma.

Objective: 
To assess the association of the immunohistochemical expression of β-catenin and
Ki67 protein tumor markers with colorectal adenocarcinoma among Sudanese patients.

Materials and methods: 
This was a descriptive study conducted at Ibn Sina Teaching
Hospital and Omdurman Teaching Hospital in Khartoum State during the period from April
2013 to December 2016. Paraffin embedded tissue samples from 75 colorectal adenocarcinoma
patients were selected and analyzed for betacatenin and Ki67 protein tumour markers expression
by the immunohistochemical technique on manual tissue microarray using the 2-step plus PolyHRP Anti-Rabbit/Mouse IgG detection system. Staining patterns were subjectively assessed and correlated with the clinico-pathological features. The results were statistically analyzed using the
Chi-square test, frequencies, and cross-tabling test.

Results: 
26 colorectal adenocarcinoma patients (34.7%) were less than 50 years old; and 49
patients (65.3%) were more than 50 years old. On the other hand, 43 patients (57.3%) were
males and 32 patients (42.7%) were females. Most of malignant tumors (38/50.7%) were well
differentiated; and 23 tumours (30.7%) were poorly differentiated tumors. Immunohistochemical
expression of betacatenin and Ki67 among colorectal adenocarcinoma patients was not
correlated with age, gender, tumor grade, metastasis, and tumor differentiation (p > 0.05).