Expression and Function Analysis of Mitotic Checkpoint Genes Identifies TTK as a Potential Therapeutic Target for Human Hepatocellular Carcinoma

Abstract

The mitotic spindle checkpoint (SAC) genes have been considered targets of anticancer therapies. Here, we sought to identify the attractive mitotic spindle checkpoint genes appropriate for human hepatocellular carcinoma (HCC) therapies. Through expression profile analysis of 137 selected mitotic spindle checkpoint genes in the publicly available microarray datasets, we showed that 13 genes were dramatically up-regulated in HCC tissues compared to normal livers and adjacent non-tumor tissues. A role of the 13 genes in proliferation was evaluated by knocking them down via small interfering RNA (siRNA) in HCC cells. As a result, several mitotic spindle checkpoint genes were required for maintaining the proliferation of HCC cells, demonstrated by cell viability assay and soft agar colony formation assay. Then we established sorafenib-resistant sublines of HCC cell lines Huh7 and HepG2. Intriguingly, increased TTK expression was significantly associated with acquired sorafenib-resistance in Huh7, HepG2 cells. More importantly, TTK was observably up-regulated in 46 (86.8%) of 53 HCC specimens. A series of in vitro and in vivo functional experiment assays showed that TTK overexpression promoted cell proliferation, anchor-dependent colony formation and resistance to sorafenib of HCC cells; TTK knockdown restrained cell growth, soft agar colony formation and resistance to sorafenib of HCC cells. Collectively, TTK plays an important role in proliferation and sorafenib resistance and could act as a potential therapeutic target for human hepatocellular carcinoma.

TC Mps1 12, a novel Mps1 inhibitor, suppresses the growth of hepatocellular carcinoma cells via the accumulation of chromosomal instability

“…A lack of Mps1 perturbs centrosome duplication (Fisk et al, 2003) (Continued) BJP M Choi et al Santaguida et al, 2010;Dou et al, 2015), a failure to correct erroneous microtubule attachment (Jelluma et al, 2008), cytokinesis failure (Fisk et al, 2003) and apoptosis (Jemaa et al, 2016), shortens mitosis (Dou et al, 2015;Jemaa et al, 2016), and prevents the recruitment of SAC-related proteins, including Mad1, Mad2, Bub1, BubR1 and RodZw10-Zwilch (Martin-Lluesma et al, 2002;Santaguida et al, 2010;Jemaa et al, 2016). In addition, depletion of (Hewitt et al, 2010) Chromosome misalignment (Dou et al, 2015) Failure in recruitment of Mad1, Mad2, Bub1 and CENP-E (Hewitt et al, 2010) Short mitotic duration (Hewitt et al, 2010;Gurden et al, 2015) Apoptosis (Jemaa et al, 2016) BAY 1161909 0.34 nM (Wengner et al, 2016) Breast, lung and ovarian cancer (Wengner et al, 2016) Phase I ClinicalTrials.gov ID: NCT02138812 BAY 1217389 0.63 nM (Wengner et al, 2016) Phase I ClinicalTrials.gov ID: NCT02366949 CFI-402257 1.7 nM (Liu et al, 2016) MPI-0479605 1.8 nM (Tardif et al, 2011) Chromosome missegregation Colon cancer (Tardif et al, 2011) Hyperploidy Apoptosis Up-regulation of p53, p21 and γ-H2AX (Tardif et al, 2011) continues Effect of Mps1 inhibitor on hepatocellular carcinoma cells BJP Mps1 inhibits proliferation of HCC cells (Liang et al, 2014;Liu et al, 2015;Miao et al, 2016). Overall, because the dysregulation of Mps1 leads to an accumulation of chromosomal instabilities and, finally, cell death, it may be a target for cancer therapeutics.…”

“…Mps1 is overexpressed in several human cancer tissues or cells including breast, glioma, liver, lung, pancreas and thyroid (Yuan et al, 2006;Salvatore et al, 2007;Landi et al, 2008;Daniel et al, 2011;Maire et al, 2013;Tannous et al, 2013;Liang et al, 2014;Slee et al, 2014). A high expression of Mps1 is associated with poor survival of patients with glioma and pancreatic cancer (Tannous et al, 2013;Slee et al, 2014;Maachani et al, 2015), although it is associated with better survival in those with triple-negative breast cancer (Maire et al, 2013).…”

Gene expression profiling, pathway analysis and subtype classification reveal molecular heterogeneity in hepatocellular carcinoma and suggest subtype specific therapeutic targets

“…TTK, which participates in the regulation of the DNA damage checkpoint, was previously reported as over-expressed in HCC (48,49). A series of in vitro and in vivo functional experiments linked TTK over-expression with resistance to sorafenib in HCC cells (48). MELK that encodes for Maternal Embryonic Leucine Zipper Kinase was found highly overexpressed in HCC and correlated with early recurrence and poor survival of patients (50).…”

“…The top 10 kinases associated genes over-expressed in HCC included TTK, MELK, BUB1, NEK2, BUB1B, AURKB, PLK1, CDK1, PKMYT1, and PBK (p < 0.05) (Table 3). TTK, which participates in the regulation of the DNA damage checkpoint, was previously reported as over-expressed in HCC (48,49). A series of in vitro and in vivo functional experiments linked TTK over-expression with resistance to sorafenib in HCC cells (48).…”

Knockdown of the differentially expressed gene TNFRSF12A inhibits hepatocellular carcinoma cell proliferation and migration in vitro

“…HCC is a tumor type that is highly insensitive to conventional chemotherapy (23), and increasingly targeted molecular therapies have exhibited significant benefits in patients with cancer, including those with HCC. The eludication of the molecular mechanism of HCC occurrence and development is important for the development of effective treatments for HCC.…”