Meiling Ji

Silencing CDR1as inhibits colorectal cancer progression through regulating microRNA-7

An increasing number of studies have demonstrated that circular RNAs (circRNAs) can regulate gene expression through interacting with microRNAs. In this study, we analyzed the expression of antisense to CDR1as in colorectal cancer (CRC). CDR1as had a higher expression in CRC tissues compared to adjacent, normal mucosa and was positively associated with tumor size, T stage, lymph node metastasis, and poor overall survival (OS). Downregulation of CDR1as suppressed CRC cell proliferation and invasion and increased microRNA-7 (miR-7) expression. Intriguingly, ectopic expression of miR-7 in CRC cells consistently inhibited proliferation and invasion, and the miR-7 inhibitor was able to rescue the function of CDR1as knockdown. Mechanistic studies demonstrated that CDR1as silencing suppressed EGFR and IGF-1R expression, which could be partially blocked by the miR-7 inhibitor. Finally, positive correlations between CDR1as expression and EGFR and IGF-1R expression were observed in CRC samples. Thus, given the importance of CDR1as in blocking miR-7 and positively regulating EGFR and IGF-1R, dysregulated CDR1as expression may play an important role in CRC progression.

Immature Colon Carcinoma Transcript-1 (ICT1) Expression Correlates with Unfavorable Prognosis and Survival in Patients with Colorectal Cancer

BackgroundColorectal cancer (CRC) is the third leading cause of death from cancer worldwide. Immature colon carcinoma transcript-1 (ICT1) has been reported to be correlated with lung cancer; however, whether ICT1 is a functional gene in CRC, as well as the molecular mechanism underlying ICT1 mediation of colorectal-tumor formation, remains unknown.MethodsThe expression of ICT1 was firstly determined by using immunohistochemistry in 861 CRC specimens. The correlation of ICT1 expression with clinicopathological parameters and the survival rate was analyzed. Furthermore, we investigated the effect of ICT1 silencing on CRC cell proliferation and migration by MTT, colony formation, flow cytometry, and transwell in vitro.ResultsICT1 is highly expressed in a cohort of human CRCs, and that higher ICT1 expression may lead to reduced overall survival rate of CRC. Likewise, ICT1 silencing lowered the cell viability through cell-cycle arrest, inhibited cell migration, and induced apoptosis in CRC. We further revealed a novel mechanism in which ICT1 promoted CRC growth via the intracellular AMPK, SAPK/JNK, and PARP signaling pathways.ConclusionsOur data showed that ICT1 could be an important target for CRC diagnosis and treatment.

Tumor deposit is a poor prognostic indicator in patients who underwent simultaneous resection for synchronous colorectal liver metastases

Background Tumor deposits are one of the important influencing factors among the different editions of Tumor, Node, Metastasis classification. Incidence and prognosis of tumor deposits in stage I, II, and III colorectal cancer patients has been explored. The aim of this study was to determine the prognostic value of tumor deposits in stage IV colorectal cancer patients who underwent simultaneous resection for synchronous colorectal liver metastases (SCRLM). Methods Clinicopathological and outcome data of 146 consecutive SCRLM patients who underwent simultaneous R0 resection between July 2003 and July 2013 were collected from our prospectively established SCRLM database. The prognostic value of tumor deposits was evaluated by Kaplan–Meier and Cox regression analysis. Results Tumor deposits were detected in 41.8% (61/146) of these SCRLM patients. Tumor deposits were significantly correlated with lymph node metastasis and nerve invasion of the primary tumors (P=0.002, P=0.041; respectively). The Kaplan–Meier survival analysis revealed that the overall survival (OS) and disease-free survival (DFS) of SCRLM patients with tumor deposits were significantly poorer than those with no tumor deposits (P=0.039, P=0.001; respectively). And with multivariate analysis, we found that positive tumor deposits were significantly associated with shorter DFS independent of lymph node status (P=0.002). Subgroup analysis found that of the 57 SCRLM patients with negative lymph node status, the OS and DFS of patients with positive tumor deposits were significantly shorter than those with negative tumor deposits (P=0.002 and P=0.031, respectively). Of the 89 patients with positive lymph node status, the OS of patients with tumor deposits was not significantly different than those without tumor deposits (P=0.965); however, the DFS of patients with tumor deposits was significantly shorter than those with no tumor deposits (P=0.034). Conclusion Tumor deposits may be an independent adverse prognostic factor in SCRLM patients who underwent simultaneous R0 resection.

Early activated hepatic stellate cell-derived paracrine molecules modulate acute liver injury and regeneration.

The effects of paracrine action from early activated hepatic stellate cells (HSCs) on resident liver epithelium cells are not clear. Here, we investigated whether a systemic infusion of early activated HSC-derived paracrine factors (HSC-CM) would evoke an enhanced liver protective response in acetaminophen (APAP)-induced acute liver injury (ALI) in mice and explored the possible underlying mechanisms. The survival rate, liver injury, and liver regeneration were analyzed in mice with or without HSC-CM treatment in vivo. A systemic infusion of HSC-CM provided a significant survival benefit in APAP-induced ALI. HSC-CM therapy resulted in a reduction of hepatocellular death and increased numbers of both proliferating hepatocytes and adult hepatic progenitor cells (AHPCs) with up-regulation of liver regeneration relevant genes. The HSC-CM treatment reduced leukocyte infiltration and down-regulated systemic inflammation with decreases in IFN-γ, IL-1ra, IL-1β, TNF-α, and increases in IL-10. The direct anti-death and pro-regeneration effects of HSC-CM on AHPCs were demonstrated using in vitro assays. Treatment with HSC-CM promoted AHPCs proliferation and resulted in increased pAkt expression in vitro, and this effect was abolished by the PI3K/Akt inhibitor LY294002. These data provide evidence that early activated HSC-CM therapy offered trophic support to the acutely injured liver by inhibiting liver cell death and stimulating regeneration, potentially creating a new method for the treatment of ALI.

Silencing homeobox C6 inhibits colorectal cancer cell proliferation.

Homeobox C6 (HOXC6), a member of the homeobox family that encodes highly conserved transcription factors, plays a vital role in various carcinomas. In this study, we used a tissue microarray (TMA) consisting of 462 CRC samples to demonstrate that HOXC6 is more abundantly expressed in colorectal cancer (CRC) tissues than adjacent normal mucosa. Clinicopathological data indicated that higher HOXC6 expression correlated with poor overall survival and was associated with primary tumor location in the right colon, primary tumor (pT) stage 3/4 and primary node (pN) stage 1/2. Multivariate analysis showed that high HOXC6 expression was an independent risk factor for poor CRC patient prognosis. HOXC6 downregulation via lentivirus-mediated expression of HOXC6-targeting shRNA reduced HCT116 cell viability and colony formation in vitro, and reduced growth of subcutaneous xenografts in nude mouse. HOXC6 thus appears to promote CRC cell proliferation and tumorigenesis through autophagy inhibition and mTOR pathway activation.

Open Right Hemicolectomy:Lateral to Medial or Medial to Lateral Approach?

Objective Currently, no published studies have compared the clinical outcomes of the medial-to-lateral approach (MA) and lateral-to-medial approach (LA) for open right hemicolectomy. Thus, the present study aimed to assess whether one of these approaches has any potential benefits over the other. Methods A retrospective study was performed of all patients who underwent open right hemicolectomy with pathologically confirmed disease who met the eligibility criteria between June 2008 and June 2012. The population was divided into an MA group and an LA group by propensity scoring. We compared patient demographic and clinical characteristic variables between the two groups and assessed short-term and long-term outcomes. Results A total of 450 patients (MA, n = 150; LA, n = 300) were evaluated. The operation time (MA,138.4 minutesvs.LA,166.2 minutes; P < .05) and blood loss (MA,52.0mL vs. LA,62.6mL; P < .05)were significantly lower in the MA group. No differences in the number of harvested lymph nodes and oncologic outcomes were observed between the two groups. Further subgroup analysis for stage III colon cancer revealed that the MA group had significantly more retrieved lymph nodes (MA,18.8vs. LA,16.0; P = .028). There were no differences in other variables between the two groups. Conclusions The MA reduced operative time and blood loss compared with the LA. We thus concluded that the MA provided short-term benefits compared with the LA in open right hemicolectomy for right-sided colon cancer.

CDKL1 promotes tumor proliferation and invasion in colorectal cancer

Background CDKL1 is a member of the cell division cycle 2 (CDC2)-related serine threonine protein kinase family and is overexpressed in malignant tumors such as melanoma, breast cancer, and gastric cancer. Objective This study aimed to evaluate whether CDKL1 can serve as a potential molecular target for colorectal cancer therapy. Materials and methods Expression of CDKL1 in colorectal cancer tissues and cell lines was measured by immunohistochemistry and Western blot, respectively. To investigate the role of CDKL1 in colorectal cancer, CDKL1-small hairpin RNA-expressing lentivirus was constructed and infected into HCT116 and Caco2 cells. The effects of RNA interference (RNAi)-mediated CDKL1 downregulation on cell proliferation and invasion were assessed by CCK-8, colony formation, transwell, and tumorigenicity assays in nude mice. The effects of CDKL1 downregulation on cell cycle and apoptosis were analyzed by flow cytometry. Furthermore, microarray method and data analysis elucidated the molecular mechanisms underlying the phenomenon. Results CDKL1 protein was overexpressed in colorectal cancer tissues compared with paired normal tissues. Knockdown of CDKL1 in HCT116 and Caco2 significantly inhibited cell growth, colony formation ability, tumor invasion, and G1–S phase transition of the cell cycle. The knockdown of CDKL1 stimulated the upregulation of p15 and retinoblastoma protein. Conclusion CDKL1 plays a vital role in tumor proliferation and invasion in colorectal cancer in vitro and in vivo and, thus, may be considered as a valuable target for therapeutic intervention.

Additional Biomarkers beyond RAS That Impact the Efficacy of Cetuximab plus Chemotherapy in mCRC: A Retrospective Biomarker Analysis

Purpose We aimed to identify new predictive biomarkers for cetuximab in first-line treatment for patients with RAS wild-type metastatic colorectal cancer (mCRC). Methods The study included patients with KRAS wild-type unresectable liver-limited mCRC treated with chemotherapy with or without cetuximab. Next-generation sequencing was done for single nucleotide polymorphism according to custom panel. Potential predictive biomarkers were identified and integrated into a predictive model within a training cohort. The model was validated in a validation cohort. Results Thirty-one of 247(12.6%) patients harbored RAS mutations. In training cohort (N=93), six potential predictive genes, namely, ATP6V1B1, CUL9, ERBB2, LY6G6D, PTCH1, and RBMXL3, were identified. According to predictive model, patients were divided into responsive group (n=66) or refractory group (n=27). In responsive group, efficacy outcomes were significantly improved by addition of cetuximab to chemotherapy. In refractory group, no benefit was observed. Interaction test was significant across all endpoints. In validation cohort (N=123), similar results were also observed. Conclusions In the first-line treatment of mCRC, the predictive model integrating six new predictive mutations divided patients well, indicating a promising approach to further refine patient selection for cetuximab on the basis of RAS mutations.

Low tumor infiltrating mast cell density confers prognostic benefit and reflects immunoactivation in colorectal cancer: Tumor infiltrating mast cell in colorectal cancer

The role of mast cells (MCs) in colorectal cancer (CRC) progression was controversial. Thus, our study was designed to evaluate the prognostic value of MCs as well as their correlation with immune microenvironment. A retrospective cohort of CRC patients of stages I–IV was enrolled in our study. Consecutive patients (854) were divided into training set (427 patients) and validation set (427 patients) randomly. The findings were further validated in a GEO cohort, GSE39582 (556 patients). The mast cell density (MCD) was measured by immunohistochemical staining of tryptase or by CIBERSORT algorithm. Low MCD predicted prolonged overall survival (OS) in training and validation set. Moreover, MCD was identified as an independent prognostic indicator in both sets. Better stratification for CRC prognosis can be achieved by building a MCD based nomogram. The prognostic role of MCD was further validated in GSE39582. In addition, MCD predicted improved survival in stages II and III CRC patients receiving adjuvant chemotherapy (ACT). Multiple immune pathways were enriched in low MCD group while cytokines/chemokines promoting anti‐tumor immunity were highly expressed in such group. Furthermore, MCD was negatively correlated with CD8+ T cells infiltration. In conclusion, MCD was identified as an independent prognostic factor, as well as a potential biomarker for ACT benefit in stages II and III CRC. Better stratification of CRC prognosis could be achieved by building a MCD based nomogram. Moreover, immunoactivation in low MCD tumors may contributed to improved prognosis.

Differences in clinical characteristics and mutational pattern between synchronous and metachronous colorectal liver metastases

Purpose To investigate differences in clinical characteristics and mutational patterns between synchronous and metachronous colorectal liver metastases (CLMs). Patients and methods From June 2008 to December 2014, patients with RAS wild-type CLMs treated at Zhongshan Hospital, Fudan University were included. DNA extracted from formalin-fixed paraffin-embedded tissue of primary tumors was sequenced with next-generation sequencing for single-nucleotide polymorphism of 96 genes according to custom panel. Mutations were compared between synchronous and metachronous liver metastases and correlated with clinical characteristics. Results A total of 161 patients were included: 93 patients with synchronous CLM and 68 patients with metachronous CLM. Patients with metachronous CLM were obviously elder. For pathology of primary tumors, synchronous CLMs were larger in size, poorly differentiated, and more frequently local advanced and lymph node positive. For evaluation of liver metastases, synchronous CLM had more and larger metastatic lesions. The median number of mutations in synchronous CLMs was significantly higher than in metachronous group (22 vs. 18, p<0.001). EGFR rs2227983 is the most prevalent mutation in both groups and only a part of prevalent mutations is shared in both groups. Prevalent mutations were correlated with many clinical characteristics. EGFR rs2227983, RBMXL3 rs12399211, and PTCH1 rs357564 were prognostic for latency of metachronous CLM. Conclusion Clinically, synchronous CLMs, compared with metachronous CLMs, were younger and showed heavier tumor burden for both primaries and liver metastases. Genetically, we identified different mutational patterns between synchronous and metachronous CLMs and several correlations between mutations and clinical characteristics. Further researches were needed to confirm these potential key mutations of CLMs.