Deciphering key regulators of Inonotus hispidus petroleum ether extract involved in anti-tumor through whole transcriptome and proteome analysis in H22 tumor-bearing mice model

Ethnopharmacological relevance: The mushroom Inonotus hispidus is traditional Chinese medicine, which has been used to treat tumor illness for a long history in China. Our previous research found that I. hispidus petroleum ether extract (IPE) has significant anti-tumor activity. However, the potential anti-tumor regulatory pathways and targets of I. hispidus remain unclear.Objective: The present study was envisaged to explore the key regulators responsible for anti-tumor of IPE using whole transcriptome and proteome analysis in H22 tumor-bearing mice model.Materials and methods: The model of H22 tumor-bearing mice was constructed according to the histopathological data and biochemical parameters. The isolated tumor tissues of different treatment groups were subjected to transcriptomic and proteomic analysis. An integrated approach of RNA-Seq, proteomics, and system biology analysis was used to identify key regulators involved in antitumor pathways. The analyzed differential expression patterns were supported by gene and protein expression studies. Results: These results indicated that 957 differentially expressed genes and 405 proteins were identified in the tumor tissue of different treatment groups through RNA-Seq and liquid chromatography with tandem mass spectrometry-based proteomic analysis, respectively. The combined omics analysis revealed five critical genes/ proteins, including Lilrb4a, Nrp1, Gzma, Gstt1, and Pdk4 that could play a role in antitumor pathways. Furthermore, Lilrb4a, Nrp1, Gzma, Gstt1 and Pdk4 genes/proteins, as key regulators of the anti-tumor effect of IPE, were verified by qRT-PCR and western blotting methods, respectively.Conclusion: Our study provides new ideas for analyzing the antitumor mechanism of IPE from the point of view of gene and protein expression and will encourage further development of the I. hispidus pharmaceutical industry.