RAD18 promotes the migration and invasion of esophageal squamous cell cancer via the JNK-MMPs pathway.

As a key regulator of DNA translesion synthesis (TLS) pathway, RAD18 is error-prone and contributes to the accumulation of DNA mutations. We have recently shown that RAD18 is overexpressed in human esophageal squamous cell cancer (ESCC) and acts to promote ESCC progression. The current study aims to understand the molecular mechanism by which RAD18 enhances the invasiveness and metastasis of ESCC cells. We found that RAD18 expression is markedly higher in high T stage ESCCs compared to low T stage groups. Kaplan-Meier analysis showed an inverse correlation between RAD18 expression and patient prognosis. The expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), two vital mediators of cell invasion and proliferation, positively correlated with RAD18 expression in ESCC tissues. Ectopic expression of RAD18 enhanced the motility and invasiveness of ESCC cells as evaluated by wound-healing assays and transwell assays. A xenograft nude mouse model showed that RAD18 promoted the colonization of ESCC cells in vivo. Signaling pathway analysis identified the JNK-MMP cascade as a mediator of RAD18-induced enhancement of ESCC progression. These data demonstrate the underlying mechanism by which RAD18 promotes ESCC progression, suggesting that RAD18 is a promising novel prognostic biomarker and therapeutic target against ESCC.

Zou S ，Yang J ，Guo J ，Su Y ，He C ，Wu J ，Yu L ，Ding WQ ，Zhou J ... -  《-》

DNA polymerase iota (Pol ι) promotes invasion and metastasis of esophageal squamous cell carcinoma.

Zou S ，Shang ZF ，Liu B ，Zhang S ，Wu J ，Huang M ，Ding WQ ，Zhou J ... -  《Oncotarget》

BRCA1-Associated Protein Increases Invasiveness of Esophageal Squamous Cell Carcinoma.

We performed a screen for genes whose expression correlates with invasiveness of esophageal squamous cell carcinoma (ESCC) cells. We studied the effects of overexpression and knockdown of these genes in cell lines and expression levels in patient samples. We selected genes for analysis from 11 loci associated with risk of ESCC. We analyzed the effects of knocking down expression of 47 of these genes using RNA interference on-chip analysis in ESCC cells and HeLa cells. Cells with gene overexpression and knockdown were analyzed in migration and invasion assays or injected into nude mice and metastasis of xenograft tumors was quantified. We collected ESCC and non-tumor esophageal tissues from 94 individuals who underwent surgery in China from 2010 and 2014; clinical information was collected and survival time was measured from the date of diagnosis to the date of last follow-up or death. Levels of messenger RNAs (mRNAs) were quantified by RNA sequencing, and levels of proteins were determined from immunoblot analyses. Patient survival was compared with mRNA levels using Kaplan-Meier methods and hazard ratios were calculated by Cox models. We identified 8 genes whose disruption increased migration and 10 genes whose disruption reduced migration. Knockdown of BRCA1-associated protein gene (BRAP) significantly reduced migration of KYSE30, KYSE150, and HeLa cells. In patient tumors, 90% of ESCCs examined had higher levels of BRAP protein than paired non-tumor tissues, and 63.8% had gains in BRAP DNA copy number. Levels of BRAP mRNA in ESCC tissues correlated with patient survival time, and high expression increased risk of death 2.4-fold compared with low expression. ESCCs that had metastasized to lymph node had significantly higher levels of BRAP mRNA than tumors without metastases. Knockdown of BRAP in ESCC and HeLa cell lines significantly reduced migration and invasiveness; these cell lines formed less metastases in mice than control cells. Nuclear translocation of the nuclear factor-κB (NF-κB) P65 subunit and phosphorylation of inhibitor of NF-κB kinase subunit β (IKBKB or IKKβ) increased in cells that overexpressed BRAP and decreased in cells with BRAP knockdown. In immunoprecipitation assays, BRAP interacted directly with IKKβ. Expression of matrix metalloproteinase 9 and vascular epithelial growth factor C, which are regulated by NF-κB, was significantly reduced in cells with knockdown of BRAP and significantly increased in cells that overexpressed BRAP. Expression of BRAP is increased in ESCC samples compared with non-tumor esophageal tissues; increased expression correlates with reduced patient survival time and promotes metastasis of xenograft tumors in mice. BRAP overexpression leads to increased activity of NF-κB and expression of matrix metalloproteinase 9 and vascular epithelial growth factor C.

Zhao Y ，Wei L ，Shao M ，Huang X ，Chang J ，Zheng J ，Chu J ，Cui Q ，Peng L ，Luo Y ，Tan W ，Tan W ，Lin D ，Wu C ... -  《-》

RNF113A promotes the proliferation, migration and invasion, and is associated with a poor prognosis of esophageal squamous cell carcinoma.

Wang L ，Hou Z ，Hasim A ，Abuduerheman A ，Zhang H ，Niyaz M ，Awut I ，Upur H ，Sheyhidin I ... -  《-》

High expression of Collagen Triple Helix Repeat Containing 1 (CTHRC1) facilitates progression of oesophageal squamous cell carcinoma through MAPK/MEK/ERK/FRA-1 activation.

Wang C ，Li Z ，Shao F ，Yang X ，Feng X ，Shi S ，Gao Y ，He J ... -  《JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH》