Research on Carbonic Anhydrase IX- an Immunohisto Chemical Marker in Renal Cell Carcinoma

Over the past two decades, Renal cell carcinoma (RCC) has become one of the lethal tumors of
growing concern among the Indian population. Carbonic anhydrase IX (CA IX) modifies intracellular
pH to aid tumor progression by regulating cell proliferation and tumor invasiveness. It is a hypoxia
inducible metalloenzyme over expressed in cancer cells. It is essential to improve the host immunity
by targeting the CAIX, thereby destroying the tumor progression and improve the survival rate. This
study was conducted using 150 tissue blocks of histopathologically proven RCC patients. The Ethics
Committee, Sri Ramachandra Institute of Higher Education & Research (Deemed University) granted
the ethical clearance. CAIX was analyzed by Biotin Streptavidin Immunoperoxidase method. Q
scoring was done. Chi square test was done to assess the comparison between the CAIX expression
in tumor cells and their characteristic features like histology, grade and stage. SPSS (version 20.0)
was used. P value <0.05 was considered significant. The aim was to assess the expression of
Carbonic Anhydrase IX in Renal Cell Carcinoma cases and its role as a potential biomarker. 74% of
RCC cases were CA IX positive whereas the adjacent normal tissue area showed negative staining.
In this study, most of the CcRCC patients (91.7%) expressed strong and diffuse staining. The intensity
of staining was inversely proportional to WHO-ISUP grading. There is a strong correlation of CA-IX
expression in early cases of clear cell RCC. It may therefore prove useful as potential diagnostic
marker, in assessing the prognosis and designing therapy in these tumors. Tumor markers provide
not only prognostic information to aid in the identification of patients at risk for recurrence or
metastasis but could also facilitate the rational use of targeted therapeutic interventions as