Detection of hypoxia-inducible factor in multiple primary malignant neoplasms of the kidney and prostate gland

Introduction. Hypoxia-inducible factor 1 (HIF-1) activates the transcription of genes involved in crucial mechanisms of cancer biology, including angiogenesis, cell survival, glucose metabolism, and invasive tumor growth. We aimed to investigate the immunohistochemical reaction level of HIF-1 in multiple primary malignancies of the kidney and prostate and compare it with that in single tumors of these organs. Materials and methods. We studied 58 archival biopsy samples of patients who underwent inpatient treatment at the Research Institute of Fundamental and Clinical Urology and Nephrology of V.I. Razumovsky Saratov State Medical University from 2012 to 2020. We analyzed patients’ medical histories and described morphological, morphometric, and immunohistochemical characteristics of biopsy samples. Results. We observed a 2-fold increase in HIF-1α immunohistochemical reaction level in multiple primary malignancies, i.e., Grades 1–2 clear cell renal cell carcinoma and acinar adenocarcinoma of the prostate with a Gleason score of 6–7. HIF-1α reaction level decreased in multiple primary malignancies of clear cell renal cell carcinoma (Grades 3–4) compared to those of highly differentiated renal cell carcinoma (Grades 1–2) and increased compared to a single renal cell carcinoma. No changes in HIF-1α reaction were found in acinar prostate adenocarcinoma. Conclusion. Increased HIF-1 reaction level in multiple primary malignancies triggers prostate cancer progression in primary diagnosed highly differentiated forms of clear cell renal cell carcinoma (Grades 1–2). Decreased HIF-1 reaction level in low-differentiated forms of renal cell carcinoma (Grades 3–4) is combined with stable reaction in prostate cancer tumour cells, which may indicate the influence of secondary processes (necrosis and concentration of the tumor microenvironment) on the tumor. Keywords: multiple primary malignant neoplasms, kidney cancer, prostate cancer, hypoxia-inducible factor