**1. Introduction**

Ivermectin is chemically derived from avermectin that was discovered and isolated from soil in Jan by Omura in 1973 [1]. It was approved by Federal Drug Administration (FDA) to use for anti-parasite drug in 1987, which has significantly improved global public health as an antiparasite medicine [2]. In 2015, its discovers Drs. Omura and Campbell earned the Nobel Prize in physiology or medicine [2]. Recent years, many studies have demonstrated that ivermectin has extensive roles in anti-bacteria, anti-virus, and anticancer, except for its anti-parasite effects [3–5]. Its anticancer effect has been shown by many *in vitro* and *in vivo* experiments in multiple cancers, including ovarian cancer, breast cancer, triple-negative breast cancer, cervical cancer, lung cancer, gastric cancer, colon cancer, glioblastoma, melanoma, and leukemia [4, 6], with a wide safe and clinically reachable drug concentration of anticancer according to its pharmacokinetic range in treatment of a parasite-infected patient [7]. It offers a promising opportunity to develop a new anticancer drug via drug repositioning of this existing compound with confirmed clinical safety [8].

assay to measure the *in vitro* effects of ivermectin in each cell. (iv)TOV-21G and SKOV3 were treated with ivermectin (0 μM, 10 μM, 20 μM, and 30 μM) for 24 h, followed by flow cytometry to measure cell cycle and cell apoptosis changes in each cell. (v) When A2780 and TOV-21G seeded in 6-well plates were grown to approximately 90% confluency, followed by the use of 10-μl pipette tip to make an artificial wound, and then treated with ivermectin (0 μM, 10 μM, 20 μM, and 30 μM) for 24 h, and measure the wound healing. The relative percentage of wound healing = (the width of wound at 0 h the width of wound at 24 h)/the width of

wound at 0 h. The detailed procedure was described previously [4, 21].

*The Anti-Cancer Effects of Anti-Parasite Drug Ivermectin in Ovarian Cancer*

*DOI: http://dx.doi.org/10.5772/intechopen.95556*

**analysis**

further experiment verification.

**2.2 Ivermectin-mediated pathway network predicted by ingenuity pathway**

**2.3 Ivermectin-mediated target molecule changes in energy metabolism**

TOV-21G and SKOV3 were treated with ivermectin (0 μM, 10 μM, 20 μM, and 30 μM) for 24 h, and 48 h. At the 24 h time point, the RNAs were extracted for quantitative real-time PCR (qRT-PCR) analysis to measure the mRNA expression of target molecules (CS, PDHB, IDH2, IDH3A, IDH3B, PFKP, PKM, MCT1, MCT4, OGDHL, ND2, ND5, CYTB, and UQCRH) in energy metabolism pathways. At the 48 h time point, the proteins were extracted for Western blot analysis to measure the protein expression of target molecules (CS, PDHB, IDH2, IDH3A, IDH3B, PFKP, PKM, MCT1, MCT4, OGDHL, ND2, ND5, CYTB, and UQCRH) in energy metabolism pathways. The detailed procedure was described previously [21].

**2.4 Ivermectin-mediated proteome changes in ovarian cancer identified by**

SILAC (stable isotope labeling with amino acids in cell culture)-based quantitative proteomics was used to identified differentially expressed proteins in ovarian cancer TOV-21G treated with and without 20 μM ivermectin [13]. The identified differentially expressed proteins were used for molecular network and signaling pathway analyses to obtain ivermectin-related signaling pathway networks [13].

**2.5 Transcriptomics and clinical data of ovarian cancer patients extracted from**

Level 3 RNA-seq V2 transcriptomics data of 411 OC patients were extracted from The Cancer Genome Atlas (TCGA) data portal (http://cancergenome.nih.gov/)

with the corresponding clinical data, including cancer status (with tumor or tumor-free), clinical stage (stages IIA, IIB, IIC, IIIA, IIIB, IIIC, and IV), neoplasm histologic grade (G1, G2, G3, G4, and GX), anatomic neoplasm subdivision (right,

left, and bilateral), age at initial pathologic diagnosis (aged from 30 to 87),

**pathways verified at the mRNA and protein levels**

**SILAC-based quantitative proteomics**

The detailed procedure was described previously [13].

**TCGA database**

**205**

The classical pathway network analysis software, Ingenuity Pathway Analysis (IPA) (http://www.ingenuity.com) [5] was used to predict ivermectin-related potential target molecules in three energy metabolism pathways. For this analysis, ivermectin and target genes in three energy metabolism pathways are all input into the IPA tool. The detailed procedure was described previously [21]. The predicted ivermectin-mediated targets in energy metabolism pathways were the basis for

Ovarian cancer, a very common cancer with high mortality and poor survival in women [9, 10], are involved in multiple signaling pathway network changes [11, 12]. Many intracellular molecules and signaling pathways would be the targets of ivermectin [13]. Ivermectin have shown a potential addition role for ovarian cancer treatment. For example, ivermectin can improve the chemosensitivity of overran cancer via targeting Akt/mTOR signaling pathway [14], and can inhibit PAK1-dependent growth of ovarian cancer cells via blocking the oncogenic kinase PAK1 [15]. Ivermectin also acts as a PAK1 inhibitor to induce autophagy in breast cancer [16]. Ivermectin can enhance p53 expression and cytochrome C release, and reduce the expression levels of CDK2, CDK4, CDK6, Bcl-2, cyclin E, and cyclin D1 in glioblastoma, those promoted the cancer cell apoptosis [17]. Ivermectin can inhibit cancer cell proliferation via decreasing YAP1 protein expression in the Hippo pathway [18]. Ivermectin represses WNT-TCF pathway in WNT-TCF-dependent disease [19]. Ivermectin can promote TFE3 (Ser321) dephosphorylation to block the binding between TFE3 and 14-3-3, and induce TFE3 accumulation in the nucleus of human melanoma cells [20]. Moreover, ivermectin also affects other signaling pathway network in human cancers, including oxidative stress, mitochondrial dysfunction, angiogenesis, epithelial-mesenchymal transition, drug resistance, and stemness in tumor [6]. Thereby, ivermectin demonstrates the potential therapeutic efficiency in multiple malignant tumors.

This book chapter discussed the anti-cancer effects of ivermectin on ovarian cancer in the following aspects: (i) ivermectin inhibited cell proliferation and growth, blocked cell cycle progression, and promoted cell apoptosis in ovarian cancer [4, 21]; (ii) ivermectin inhibited ovarian cancer growth through molecular networks to target the key molecules in energy metabolism pathways, including glycolysis, Kreb's cycle, oxidative phosphorylation, and lactate shuttle pathways [21]; (iii) Integrated omics revealed that ivermectin mediated lncRNA-EIF4A3 mRNA axes in ovarian cancer to exert its anticancer capability [4, 13]; and (iv) lasso regression identified the prognostic model of ivermectin-related three-lncRNA signature (ZNRF3-AS1, SOS1-IT1, and LINC00565) that is significantly related to overall survival and clinicopathologic characteristics of ovarian cancers [4].
