In our study, two members of the MMP family, MMP-14 and MMP-28, had increased expression resulting from HIF-1α overexpression in the in vitro microarray experiment and in the CAM experiments. The increased Lazertinib price expression of MMP-14 has been identified as a negative predictor of survival in SCLC [41], and the targeted drug inhibiting MMP-14 expression, marimastat [42], has been used in clinical studies. MMP-28 is expressed at low levels in normal lung tissue, but the expression of MMP-28 is highly increased after cancer formation [43]. MMP-28 induces epithelial-mesenchymal transitions (EMT), which yield tumor cells with collagen-invasive properties allowing the invasion of collagen matrices

[44]. The upregulation of MMP-28 by HIF-1α enhances this ability. The expression level of angiogenic factors is the gold standard to measure the angiogenic potential of tumors, and the inhibition of the expression of angiogenic factors is the primary treatment for SCLC. Angiogenic factors that are significantly regulated by HIF-1α in a hypoxic selleck kinase inhibitor microenvironment are also therapeutic target points [45]. In addition to VEGF, FGF-2 [46], ANG-2 [47], HIF-2α [48], and PDGFC are also involved in tumor angiogenesis. In this study, three inflammatory factors, IL-6, TNFAIP6, and IL1R1, were upregulated by HIF-1α. These inflammatory factors actively responded during the process of inflammatory

angiogenesis. TNFAIP6 is the stimulating factor for TNF-α [49], and IL-1R1 is the receptor for IL-1 [50]. IL-6 and VEGF-A have synergistic effects in stimulating the proliferation and invasiveness of tumors by promoting angiogenesis [51]. Our results indicate that HIF-1α may enhance the inflammatory reaction or stimulate

the secretion of coherent inflammatory factors to promote the angiogenesis of SCLC, which highlights the importance of anti-inflammation for the treatment of SCLC as some scholars have suggested [52]. In addition, the TNC, FN1, and HMOX1 cytokines were screen out by microarray analysis. TNC is an extracellular matrix protein with angiogenesis-promoting activities, Amobarbital and it has specific functions in vessel formation [53]. FN1 has been shown to be an angiogenic cytokine involved in angiogenesis during several pathological processes, such as psoriasis, diabetic retinopathy, and cancer [54]. The overexpression of HMOX1 has been observed in liver cancer [55], pancreatic cancer [56], and melanomas [57]. Targeting these cytokines for gene therapy of SCLC in the future requires their verification in clinical trials. Conclusions Overall, our results suggest that HIF-1α significantly promotes the growth and angiogenesis of NCI-H446 cells by upregulating the expression of angiogenic genes. Moreover, our use of the chick CAM as an in vivo experimental model further confirms the expression of these genes induced by HIF-1α.