Intrabody Targeting HIF-1α Mediates Transcriptional Downregulation of Target Genes Related to Solid Tumors

Abstract

Uncontrolled growth of solid tumors will result in a hallmark hypoxic condition, whereby the key transcriptional regulator of hypoxia inducible factor-1α (HIF-1α) will be stabilized to activate the transcription of target genes that are responsible for the metabolism, proliferation, and metastasis of tumor cells. Targeting and inhibiting the transcriptional activity of HIF-1 may provide an interesting strategy for cancer therapy. In the present study, an immune library and a synthetic library were constructed for the phage display selection of Nbs against recombinant PAS B domain protein (rPasB) of HIF-1α. After panning and screening, seven different nanobodies (Nbs) were selected, of which five were confirmed via immunoprecipitation to target the native HIF-1α subunit. The inhibitory effect of the selected Nbs on HIF-1 induced activation of target genes has been evaluated after intracellular expression of these Nbs in HeLa cells. The dramatic inhibition of both intrabody formats on the expression of HIF-1-related target genes has been confirmed, which indicated the inhibitory efficacy of selected Nbs on the transcriptional activity of HIF-1.

Development and characterization of nanobodies that specifically target the oncogenic Phosphatase of Regenerating Liver-3 (PRL-3) and impact its interaction with a known binding partner, CNNM3

“…Intrabodies allow for the expression of nanobody cDNA fused to a reporter gene to be expressed in the cell in the same way we have over-expressed PRL-3 [ 52 ]. Many groups have developed intrabodies against disease related targets, including HIF-1α [ 53 ], HPV16 E6 [ 54 ], Ras [ 55 ], and many others. The primary challenge in intrabody development is that the reducing environment of the cytosol can impact the formation of the disulfide bonds needed for nanobody folding, which can negatively impact nanobody-reporter gene folding ang the ability of the intrabody to recognize its target [ 56 ].…”

Penehyclidine Hydrochloride Improves Rhabdomyolysis-Mediated Acute Kidney Injury by Inhibiting Ferroptosis through the HIF-1α/MT1G Axis

“…Herein, HIF-1 was significantly increased in FeG-treated HK-2 cells and kidney tissues of glycerol-treated rats, while PHC therapy might alleviate HIF-1 overexpression in RM-induced AKI. As widely described, HIF-1α achieves its roles through transcriptional regulation of downstream genes [31]. Herein, HIF-1α was predicted to have potential binding sites to MT1G promoter by using the JASPAR database.…”

Hypoxia Enhances HIF1α Transcription Activity by Upregulating KDM4A and Mediating H3K9me3, Thus Inducing Ferroptosis Resistance in Cervical Cancer Cells

“…Uncontrolled multiplication of solid tumors leads to an evident hypoxic condition status [ 36 ]. Existing research supports the idea of hypoxia being a negative influencing factor in CC treatment and reveals that hypoxia induces resistance to cisplatin in CC cells [ 37 ].…”