Immunohistochemical studies for identification of biomarkers in haematological malignancies: An approach for potential novel therapeutic targets

Lymphoid neoplasms are a subgroup of haematological malignancies that affect circulating lymphocytes. The clinical and biological heterogeneity of lymphoid neoplasms can lead to difficulty in accurate diagnosis in this group of diseases. The advancement in effective and feasible detection platforms has enabled novel biomarkers to improve diagnosis and prognosis, in addition to assist in patient stratification and personalised treatments for these diseases. Although there have been improvements in high-throughput diagnostic techniques, the conventional immunohistochemistry (IHC) remains the most widely used platform for biomarker assessment in the field of tissue pathology. As this conventional technique has certain limitations, multiplex IHC (MIHC) approaches have found ways to overcome these challenges, therefore becoming the main focus of immunotherapy for lymphoid neoplasms. This particular effective and proficient technology can simultaneously target multiple molecule/protein of interest within the tumor microenvironment to determine the status of immune cell activation and the presence of protein expression. MIHC is advantageous in providing information about the underlying immune evasion mechanisms, which play a vital role in the development of prognostic and diagnostic biomarkers. This thesis focuses on the novel use of IHC/MIHC approaches and their current role in biomarker development to be used in diagnosis, prognosis, and the potential treatment strategies within haematological malignancies in specific lymphoid neoplasms.