An In Silico Investigation of SPC24 as a Putative Biomarker of Kidney Renal Clear Cell Carcinoma and Kidney Renal Papillary Cell Carcinoma for Predicting Prognosis and/or Immune Infiltration

Background and Objective: SPC24 was reported to be correlated with the development of many cancers. However, its role in renal cancer was unclear. Our aim was to explore the role of SPC24 in kidney renal clear cell carcinoma (KIRC) and kidney renal papillary cell carcinoma (KIRP) in types of renal cancer. Methods: SPC24 expressions in KIRC and KIRP were firstly analyzed. Subsequently, the correlation between SPC24 expression and TNM staging of KIRC and KIRP and the accuracy of SPC24 in diagnosing KIRC and KIRP were explored. Moreover, the correlation between SPC24 expression and prognosis of KIRC and KIRP were analyzed. Univariate and multivariate analyses were performed to identify prognostic factors in KIRC and KIRP, and nomograms were constructed. The correlation between SPC24 expression and immune cell infiltration, immune molecules, microsatellite instability (MSI), and tumor mutational burden (TMB) were further explored. Finally, the correlations between SPC24 expression and prognosis of KIRC based on different immune cell enrichment were analyzed. Results: SPC24 was significantly up-regulated in multiple cancers, especially KIRC and KIRP. SPC24 expression was significantly correlated with the TNM stage of KIRC and KIRP, and up-regulated SPC24 suggested a worse prognosis. Besides, SPC24 possesses good accuracy in diagnosing KIRC and KIRP. The SPC24-based nomograms displayed satisfactory efficacy in KIRC and KIRP. Moreover, we found that SPC24 expression was closely correlated with immune cell infiltration, immune molecules, and TMB in KIRC, and up-regulated SPC24 revealed poor prognosis based on different immune cell enrichment. Conclusion: SPC24 has the potential to be a biomarker predicting the prognosis and/or immune infiltration of KIRC and KIRP.