Targeting Hypoxia-Inducible Factor-1α for the Management of Hepatocellular Carcinoma

Effect of RNA interference with HIF-1α on the growth of pulmonary artery endothelial cells in broiler chickens

Pulmonary artery remodeling is a characteristic feature of broiler ascites syndrome (BAS). Pulmonary artery endothelial cells (PAECs) regulated by HIF-1α play a critical role in pulmonary artery remodeling, but the underlying mechanisms of HIF-1α in BAS remain unclear. In this experiment, primary PAECs were cultured in vitro and were identified by coagulation factor VIII. After hypoxia and RNA interference, the mRNA and protein expression levels of HIF-1α and VEGF were determined by qPCR and Western blotting. The transcriptome profiles of PAECs were obtained by RNA sequencing. Our results showed that the positive rate of PAECs was more than 90%, hypoxia-induced promoted the proliferation and apoptosis of PAECs, and RNA interference significantly downregulated the expression of HIF-1α, inhibited the proliferation of PAECs, and promoted the apoptosis of PAECs. In addition, transcriptome sequencing analysis indicated that HIF-1α may regulate broiler ascites syndrome by mediating COL4A, vitronectin, vWF, ITGα8, and MKP-5 in the ECM, CAMs and MAPK pathways in PAECs. These studies lay the foundation for further exploration of the mechanisms of pulmonary artery remodeling, and HIF-1α may be a potentially effective gene for the prevention and treatment of BAS.

Targeting metabolic reprogramming promotes the efficacy of transarterial chemoembolization in the rabbit VX2 liver tumor model

Transarterial chemoembolization (TACE) may prolong the survival of patients with hepatocellular carcinoma (HCC); however, its efficacy is limited due to the high rate of incomplete embolization. Hypoxia after embolization can cause a series of changes in the tumor microenvironment, including lactate dehydrogenase A (LDHA) upregulation. Therefore, the current study assessed the antitumor effect and the underlying mechanism of the LDHA inhibitor, sodium oxamate (Ox), combined with TACE, using the rabbit VX2 liver tumor model. VX2 liver tumor models were created in the left liver lobe of rabbits, and after 14 days of treatments, the rabbits were sacrificed for the collection of the tumor tissues and blood samples. The antitumor effects of Ox, and the combination of Ox and TACE, and changes in the tumor microenvironment after treatments were assessed by histopathological evaluation, and the safety of the treatments was analyzed by measuring changes in the serum levels of alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen and creatinine. The results demonstrated that the combination of Ox and TACE notably improved antitumor effects compared with in the other groups, as it significantly inhibited tumor growth. Additionally, treatment with Ox + TACE downregulated vascular endothelial growth factor and matrix metalloproteinase-9, and enhanced the infiltration of CD3+ and CD8+ T cells into tumor tissues, thus suggesting that Ox + TACE may have a synergistic effect on increasing the infiltration of immune cells in the tumor microenvironment. With a well-tolerated and manageable impairment of hepatorenal function, targeting metabolic reprogramming could promote the efficacy of TACE, thus providing novel avenues for the future clinical management of patients with advanced HCC.

Targeting Hypoxia-Inducible Factor-1 (HIF-1) in Cancer: Emerging Therapeutic Strategies and Pathway Regulation

Hypoxia-inducible factor-1 (HIF-1) is a key regulator for balancing oxygen in the cells. It is a transcription factor that regulates the expression of target genes involved in oxygen homeostasis in response to hypoxia. Recently, research has demonstrated the multiple roles of HIF-1 in the pathophysiology of various diseases, including cancer. It is a crucial mediator of the hypoxic response and regulator of oxygen metabolism, thus contributing to tumor development and progression. Studies showed that the expression of the HIF-1α subunit is significantly upregulated in cancer cells and promotes tumor survival by multiple mechanisms. In addition, HIF-1 has potential contributing roles in cancer progression, including cell division, survival, proliferation, angiogenesis, and metastasis. Moreover, HIF-1 has a role in regulating cellular metabolic pathways, particularly the anaerobic metabolism of glucose. Given its significant and potential roles in cancer development and progression, it has been an intriguing therapeutic target for cancer research. Several compounds targeting HIF-1-associated processes are now being used to treat different types of cancer. This review outlines emerging therapeutic strategies that target HIF-1 as well as the relevance and regulation of the HIF-1 pathways in cancer. Moreover, it addresses the employment of nanotechnology in developing these promising strategies.

Advances in macrophage and T cell metabolic reprogramming and immunotherapy in the tumor microenvironment

Macrophages and T cells in the tumor microenvironment (TME) play an important role in tumorigenesis and progression. However, TME is also characterized by metabolic reprogramming, which may affect macrophage and metabolic activity of T cells and promote tumor escape. Immunotherapy is an approach to fight tumors by stimulating the immune system in the host, but requires support and modulation of cellular metabolism. In this process, the metabolic roles of macrophages and T cells become increasingly important, and their metabolic status and interactions play a critical role in the success of immunotherapy. Therefore, understanding the metabolic state of T cells and macrophages in the TME and the impact of metabolic reprogramming on tumor therapy will help optimize subsequent immunotherapy strategies.