Expression of Heat Shock Protein 90 in Testicular Cancer: A Retrospective Cohort Study.

Abstract

Background: The HSP90 marker is believed to play a constructive role in facilitating neoplastic transformation mainly via interaction with multiple pro-survival proteins. Welldesigned studies are needed to elucidate the role of HSP90 as a diagnostic marker and therapeutic target in testicular tumors.

Objective: The current study aimed to investigate the expression of HSP90 in various types of testicular cancer and highlight its expression in embryonal testicular cancer.

Material and methods: Immunohistochemical staining for HSP90 in 84 male patients, with nonmetastatic testicular cancer, who underwent orchiectomy from 2000 to 2023, was retrospectively performed at the Laboratory Department of General Hospital of Nikaia in Greece.

Results: A total of 84 males, with a mean age of 36.2 years, who have undergone high-cord radical orchiectomy, were included in this study. Out of the included males, 28.57% had embryonal carcinoma, 23.81% had seminoma, 19.05% had yolk sac tumor, 11.9% had mature teratoma, 9.52% had immature teratoma, and 7.14% had choriocarcinoma. HSP90b was positive in all embryonal carcinoma, seminoma, and choriocarcinoma cases, while it was positive in 75% of the yolk sac tumor, 75% of mature teratoma, and 75% of immature teratoma specimens. HSP90 was found negative in all choriocarcinoma, mature teratoma, and immature teratoma specimens, while it was positive in 25% of yolk sac tumor, 8.33% of embryonal carcinoma, and 10% of seminoma cases. Concerning the expression of HSP90b, a statistically significant relationship was found between excised tumor specimens and normal parenchyma specimens, especially in sac cases (p <0.001). Regarding HSP90a expression, a statistically significant relationship (OR=21.5, p =0.021) was found between excised tumor specimens and normal parenchyma specimens, especially in embryonal carcinoma cases (p <0.001).

Conclusion: HSP90b is highly expressed in the majority of the types of testicular tumors, both in tumor and normal parenchyma specimens, while HSP90a staining is negative in resected specimens. Further well-designed studies are needed to elucidate the role of HSP90 as a diagnostic marker and therapeutic target in testicular tumors.