Prognostic Relevance of Id-1 Expression in Patients With Resectable Esophageal Squamous Cell Carcinoma

Employing siRNA tool and its delivery platforms in suppressing cisplatin resistance: Approaching to a new era of cancer chemotherapy

Although chemotherapy is a first option in treatment of cancer patients, drug resistance has led to its failure, requiring strategies to overcome it. Cancer cells are capable of switching among molecular pathways to ensure their proliferation and metastasis, leading to their resistance to chemotherapy. The molecular pathways and mechanisms that are responsible for cancer progression and growth, can be negatively affected for providing chemosensitivity. Small interfering RNA (siRNA) is a powerful tool extensively applied in cancer therapy in both pre-clinical (in vitro and in vivo) and clinical studies because of its potential in suppressing tumor-promoting factors. As such oncogene pathways account for cisplatin (CP) resistance, their targeting by siRNA plays an important role in reversing chemoresistance. In the present review, application of siRNA for suppressing CP resistance is discussed. The first priority of using siRNA is sensitizing cancer cells to CP-mediated apoptosis via down-regulating survivin, ATG7, Bcl-2, Bcl-xl, and XIAP. The cancer stem cell properties and related molecular pathways including ID1, Oct-4 and nanog are inhibited by siRNA in CP sensitivity. Cell cycle arrest and enhanced accumulation of CP in cancer cells can be obtained using siRNA. In overcoming siRNA challenges such as off-targeting feature and degradation, carriers including nanoparticles and biological carriers have been applied. These carriers are important in enhancing cellular accumulation of siRNA, elevating gene silencing efficacy and reversing CP resistance.

Micellar Casein and Whey Powder Hold a TGF-β Activity and Regulate ID Genes In Vitro

Casein and whey being food supplements have been considered to be used in oral health care products. However, the response of oral cells to micellar casein and whey powder remains unclear. Considering that milk contains the growth factor TGF-β, and lactoperoxidase was recently reported to decrease the expression of inhibitor of DNA-binding (ID) proteins, there is a rationale to assume that casein and whey can also provoke these responses in oral cells. To examine the TGF-β activity, gingival fibroblasts were exposed to reconstituted casein and whey powder from food supplement before the expression of TGF-β target genes were analyzed by reverse transcription-quantitative polymerase chain reaction. Immunoassays were performed for interleukin11 (IL11) in the cell culture supernatant and for TGF-β in the reconstituted casein and whey. We blocked TGF-β by neutralizing the antibody and the TGF-β receptor type I kinase with the inhibitor SB431542. We also showed smad3 phosphorylation and smad2/3 nuclear translocation by Western blot and immunostaining, respectively. Moreover, with reconstituted casein and whey powder, ID1 and ID3 expression analysis was evaluated in HSC2 human oral squamous carcinoma cells. We report here that casein and whey powder caused a robust increase of TGF-β target genes interleukin11 (IL11), NADPH oxidase 4 (NOX4) and proteoglycan4 (PRG4) in gingival fibroblasts that was blocked by SB431542 and the neutralizing antibody. Moreover, casein and whey powder increased the phosphorylation of smad3 and nuclear translocation of smad2/3. No changes of proliferation markers Ki67 and cyclinD1 were observed. Furthermore, reconstituted casein and whey powder decreased ID1 and ID3 expression in the HSC2 oral squamous carcinoma cells. These findings suggest that the processing of milk into casein and whey powder maintains the TGF-β activity and its capacity to regulate ID1 and ID3 genes in oral fibroblasts and oral squamous carcinoma cells, respectively. These data increase the scientific knowledge on the biological activity of casein and whey with a special emphasis on oral health.

LEF1/Id3/HRAS axis promotes the tumorigenesis and progression of esophageal squamous cell carcinoma

Our previous study demonstrated that lymphoid enhancer-binding factor 1 (LEF1) could promote the progression of esophageal squamous cell carcinoma (ESCC). However, the regulatory mechanism of LEF1 was not clear thoroughly. Herein, we continued to explore the downstream mechanism of LEF1 in ESCC. In this study, we applied western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), immunohistochemistry, RNA-Seq analysis, a luciferase reporter assay, chromatin immunoprecipitation (ChIP), bioinformatics analysis, and a series of functional assays in vitro and in vivo. The results demonstrated that LEF1 regulated directly the expression of Id3. Id3 was highly expressed in ESCC tissues and correlated with histologic differentiation (p=0.011), pT stage (p<0.01) and AJCC stage (p<0.01) in ESCC patients. Moreover, Id3 could serve as a prognostic factor of ESCC. By various functional experiments, overexpression of Id3 promoted the proliferation, migration, invasion, EMT, and tumorgenicity. Mechanistically, Id3 could regulate ERK/MAPK signaling pathway via activating HRAS to perform its biological function. Furthermore, activating ERK/MAPK signaling pathway promoted the expression of Id3 gene in turn, indicating that a positive regulatory loop between Id3 and ERK/MAPK pathway may exist in ESCC. In summary, LEF1/Id3/HRAS axis could promote the tumorigenesis and progression of ESCC via activating ERK/MAPK signaling pathway. Targeting this cascade may provide a valid antitumor strategy to delay ESCC progress.

MicroRNA-338-5p reverses chemoresistance and inhibits invasion of esophageal squamous cell carcinoma cells by targeting Id-1

5-Fluorouracil (5-FU) is a chemotherapeutic agent commonly used to treat esophageal squamous cell carcinoma (ESCC), but acquisition of chemoresistance frequently occurs and the underlying mechanisms are not fully understood. We found that microRNA (miR)-338-5p was underexpressed in ESCC cells with acquired 5-FU chemoresistance. Forced expression of miR-338-5p in these cells resulted in downregulation of Id-1, and restoration of both in vitro and in vivo sensitivity to 5-FU treatment. The effects were abolished by reexpression of Id-1. In contrast, miR-338-5p knockdown induced 5-FU resistance in chemosensitive esophageal cell lines, and knockdown of both miR-338-5p and Id-1 resensitized the cells to 5-FU. In addition, miR-338-5p had suppressive effects on migration and invasion of ESCC cells. Luciferase reporter assay confirmed a direct interaction between miR-338-5p and the 3'-UTR of Id-1. We also found that miR-338-5p was significantly downregulated in tumor tissue and serum samples of patients with ESCC. Notably, low serum miR-338-5p expression level was associated with poorer survival and poor response to 5-FU/cisplatin-based neoadjuvant chemoradiotherapy. In summary, we found that miR-338-5p can modulate 5-FU chemoresistance and inhibit invasion-related functions in ESCC by negatively regulating Id-1, and that serum miR-338-5p could be a novel noninvasive prognostic and predictive biomarker in ESCC.

Inhibitor of DNA binding 1 (Id1) mediates stemness of colorectal cancer cells through the Id1-c-Myc-PLAC8 axis via the Wnt/β-catenin and Shh signaling pathways

Background

Inhibitor of DNA binding 1 (Id1) is upregulated in multiple cancers, and Id1overexpression correlates with cancer aggressiveness and poor clinical outcomes in cancer patients. However, its roles in cancer stem-like cells (CSCs) and epithelial-mesenchymal transition (EMT) are still elusive.

Purpose

This study aimed to examine the role of Id1 on the mediation of CRC stemness and explore the underlying mechanisms.

Methods

Id1 and CD133 expression was detected by qPCR assay and immunohistochemistry (IHC) in normal mucosal and primary colorectal cancer (CRC) specimens. Id1 was stably knocked down (KD) in human CRC cell lines. Spheres forming assay and tumorigenic assay were performed to evaluate self-renewal capacity and tumor initiation. Expression of CSC- and EMT-related markers and TCF/LEF activity were assessed in HCT116 cells after Id1 KD.

Results

qPCR assay showed higher Id1 and CD133 expression in CRC specimens than in normal mucosal specimens (P<0.05). IHC detected high cytoplasmic Id1 expression in 35 CRC specimens (46.7%), and high CD133 expression in 22 CRC specimens (29.3%) and negative expression in 18 normal mucosal specimens. High Id1 expression positively correlated with poor differentiation (P=0.034), and CD133 expression correlated with T category in CRC patients (P=0.002). Spearman correlation analysis revealed a positive correlation between Id1 and CD133 expression in CRC patients (P<0.05). Id1 KD resulted in suppression of proliferation, cell-colony formation, self-renewal capability and CSC-like features in HCT116 cells, and impaired the tumor-initiating capability in CRC cells. In addition, Id1 maintained the stemness of CRC cells via the Id1-c-Myc-PLAC8 axis through activating the Wnt/β-catenin and Shh signaling pathways.

Conclusions

Id1 expression significantly correlates with CD133 expression in CRC patients, and Id1 KD impairs CSC-like capacity and reverses EMT traits, partially via the Wnt/β-catenin signaling. Id1 may be a promising therapeutic target against colon CSCs.

Strong expression of Id-1 in metastatic lymph nodes from esophageal squamous cell carcinoma is associated with better clinical outcome

Background

Over-expression of inhibitor of differentiation or DNA binding 1 (Id-1) is associated with poor prognosis in esophageal squamous cell carcinoma (ESCC). However, some biomarkers discordant expression in metastasis has been reported previously. We aimed to confirm possible differential expression and prognostic value of Id-1 in paired metastatic lymph node (PMLN).

Methods

Expression of Id-1 in primary tumors (PT) and paired regional metastatic lymph nodes of ESCC were evaluated with immunohistochemical (IHC) analysis. Statistical analysis of Kaplan-Meier method was performed to test the prognostic significance of Id-1 expression.

Results

The expression of Id-1 was down-regulated in metastatic lymph nodes compared with primary esophageal tumors (P<0.001). Patients with 1 to 2 lymph nodes involved had significantly higher Id-1 expression in metastatic lymph nodes (P=0.028). The similar association was observed between a ratio of involved to examined lymph nodes ≤0.2 and high level Id-1 expression in lymphatic metastases (P=0.011). Better overall survival with statistical significance was observed in patients with higher level Id-1 expression in metastatic lymph nodes (P=0.015). The results of Id-1 expression in metastatic lymph node and paired PT was to predict prognosis effective in out cohort (P=0.035).

Conclusions

The level of Id-1 protein expression was down-regulated from PT to metastatic lymph node. It was contrary to previous studies that strong expression of Id-1 in metastatic lymph nodes was associated with better clinical outcomes in patients with stage T3N1-3M0 ESCC.

Autophagy Inhibitor (LY294002) and 5-fluorouracil (5-FU) Combination-Based Nanoliposome for Enhanced Efficacy Against Esophageal Squamous Cell Carcinoma

In this study, 5-fluorouracil (5-FU) and LY294002 (LY)-loaded PEGylated nanoliposome was prepared to target esophageal squamous cell carcinoma (ESCC). The particles were characterized in terms of physicochemical and biological parameters. The co-delivery of autophagy inhibitor and chemotherapeutic drug in a single carrier was successfully accomplished. The two components from 5-FU and LY-loaded PEGylated nanoliposome (FLNP) released in a controlled manner with LY relatively released faster compared to that of 5-FU. FLNP showed a receptor-mediated cellular uptake that will allow the gradual release of drug in the acidic environment. The cellular uptake of nanoparticles (NP) was further confirmed by FACS analysis. The combination of 5-FU and LY resulted in higher cytotoxic effect compared to that of individual drugs. Most importantly, FLNP exhibited a significantly higher anticancer effect in cancer cells compared to that of free cocktail combinations. The faster release of LY from FLNP leads to autophagy inhibition that improves the sensitivity of cancer cells towards 5-FU, resulting in more cell death. Consistently, FLNP induced a greater apoptosis (~ 48%) of cancer cells compared to that of any other groups. Western blot analysis clearly showed that 5-FU and LY individually increased the expression of caspase-3 and PARP, while as expected FLNP induced a remarkable expression of these protein markers indicating the superior anticancer effect. We believe that the programmed release of autophagy inhibitor and chemotherapeutic drug from a single nanocarrier will increase the prospect of anticancer therapy in ESCC.

KIF-2C expression is correlated with poor prognosis of operable esophageal squamous cell carcinoma male patients

To determine the prognostic significance of Kinesin family member 2C (KIF-2C) expression in patients with operable esophageal squamous cell carcinoma (ESCC), we conducted an immunohistochemical analysis of KIF-2C expression in 415 surgically resected primary tumor tissues and 40 adjacent non-cancerous tissues from patients with operable ESCC. The median duration of postoperative follow-up was 76.0 months. Higher KIF-2C expression was associated with significantly increased risks of higher pathologic tumor (pT) status (P=0.038) and poorer tumor differentiation (P=0.022). For the entire cohort, KIF-2C expression was not an independent factor significantly associated with overall survival (OS) (P=0.097) or disease-free survival (DFS) (P=0.152). In female patients, KIF-2C expression had no effect on OS (P=0.880) and DFS (P=0.864). However, OS (hazard ratio (HR)=1.480, P=0.013) and DFS (HR=1.418, P=0.024) were worse for male patients with high KIF-2C expression compared with male patients with low KIF-2C expression. Moreover, the OS and DFS of male patients with high KIF-2C expression were also significantly shorter compared with female patients with low KIF-2C expression (P=0.022, P=0.029) and female patients with high KIF-2C expression (P=0.014, P=0.018). Based on these findings, KIF-2C expression in tumor tissues promises to serve as an independent prognostic marker for male, but not female, patients with operable ESCC. Prognosis was worse for male patients with high KIF-2C expression compared with patients with the same pathologic tumor-node-metastasis (pTNM) stage.

siRNA-mediated knockdown of ID1 disrupts Nanog- and Oct-4-mediated cancer stem cell-likeness and resistance to chemotherapy in gastric cancer cells

DNA-binding protein inhibitor ID-1 (ID1) serves an essential role in tumor progression, and the self-renewal and pluripotency of embryonic stem cells. However, the effect of ID1 on the stemness and cancer stem cell (CSC)-like properties of gastric adenocarcinoma cells remains to be elucidated. In the present study, effective ID1 knockdown was achieved in gastric cancer (GC) cells using small interfering RNA, and the self-renewal ability and cisplatin (DDP) sensitivity of GC cells was subsequently examined. ID1 knockdown in the MKN-28 and MGC-803 cell lines was demonstrated to significantly suppress colony formation (P=0.005 in MKN-28 and P=0.001 in MGC-803), tumor spheroid formation (P=0.021 in MKN-28 and P=0.037 in MGC-803), cell proliferation (P=0.028 in MKN-28 and P=0.001 in MGC-803) and migration (P=0.002 in MKN-28 and P=0.015 in MGC-803). To the best of our knowledge, the present study revealed for the first time that ID1 knockdown suppresses the expression of the key CSC-associated factors Nanog and octamer-binding protein 4 (Oct-4). It was further demonstrated that ID1 knockdown sensitized GC cells to DDP. In conclusion, knockdown of ID1 attenuates the stem cell like-properties of self-renewal in normal GC cells, potentially through the targeting of Nanog and Oct-4, and subsequently decreases cell proliferation and resistance to DDP. The results of the present study suggest that ID1 functions as an oncogene in GC and regulates the stem cell like-properties of gastric cancer cells by targeting Nanog and Oct-4.

Cancer cell-secreted IGF2 instigates fibroblasts and bone marrow-derived vascular progenitor cells to promote cancer progression

Local interactions between cancer cells and stroma can produce systemic effects on distant organs to govern cancer progression. Here we show that IGF2 secreted by inhibitor of differentiation (Id1)-overexpressing oesophageal cancer cells instigates VEGFR1-positive bone marrow cells in the tumour macroenvironment to form pre-metastatic niches at distant sites by increasing VEGF secretion from cancer-associated fibroblasts. Cancer cells are then attracted to the metastatic site via the CXCL5/CXCR2 axis. Bone marrow cells transplanted from nude mice bearing Id1-overexpressing oesophageal tumours enhance tumour growth and metastasis in recipient mice, whereas systemic administration of VEGFR1 antibody abrogates these effects. Mechanistically, IGF2 regulates VEGF in fibroblasts via miR-29c in a p53-dependent manner. Analysis of patient serum samples showed that concurrent elevation of IGF2 and VEGF levels may serve as a prognostic biomarker for oesophageal cancer. These findings suggest that the Id1/IGF2/VEGF/VEGFR1 cascade plays a critical role in tumour-driven pathophysiological processes underlying cancer progression.

Identification and Validation of Lymphovascular Invasion as a Prognostic and Staging Factor in Node-Negative Esophageal Squamous Cell Carcinoma

INTRODUCTION

Lymphovascular invasion (LVI) is a histopathological feature that is associated with an increased risk for micrometastasis. The aim of this study was to determine the prognostic and staging value of LVI among patients with esophageal squamous cell carcinoma (ESCC) undergoing esophagectomy.

METHODS

A prospective database of patients with ESCC was used to retrospectively analyze 666 cases to identify the relationship between LVI and survival, and to evaluate predictive accuracy of prognosis after combining LVI and the tumor, node, and metastasis (TNM) system. Pathological slides were reassessed by gastrointestinal pathologists according to the strict criteria; 1000-bootstrap resampling was used for internal validation, and 222 cases from an independent multicenter database were used for external validation.

RESULTS

LVI was present in 33.8% of patients, and the proportion increased with advancing T and N classification. LVI was an independent predictor of unfavorable disease-specific survival (DSS) (hazard ratio = 1.59, 95% confidence interval: 1.30-1.94) and disease-free survival (DFS) (hazard ratio = 1.62, 95% confidence interval: 1.32-1.98) after T classification. Among node-negative patients, LVI and T classification were two independent predictors of DSS and DFS (p < 0.001). The risk score model combing LVI and T classification improved the predictive accuracy of the TNM system for DSS and DFS by 3.5% and 4.8%, respectively (p < 0.001). The external validation showed congruent results. The DSS of TxN0MO disease with LVI was similar to the DSS of TxN1M0 (both p > 0.05). In contrast, LVI was not associated with DSS or DFS among node-positive patients.

CONCLUSIONS

The independent prognostic significance of LVI existed only in node-negative patients with ESCC, and the combination of LVI and the TNM system enhanced the predictive accuracy of prognosis. After confirmation, node-negative patients with LVI might be considered for upstaging in pathological staging.

ID proteins regulate diverse aspects of cancer progression and provide novel therapeutic opportunities

The inhibitor of differentiation (ID) proteins are helix-loop-helix transcriptional repressors with established roles in stem cell self-renewal, lineage commitment, and niche interactions. While deregulated expression of ID proteins in cancer was identified more than a decade ago, emerging evidence has revealed a central role for ID proteins in neoplastic progression of multiple tumor types that often mirrors their function in physiological stem and progenitor cells. ID proteins are required for the maintenance of cancer stem cells, self-renewal, and proliferation in a range of malignancies. Furthermore, ID proteins promote metastatic dissemination through their role in remodeling the tumor microenvironment and by promoting tumor-associated endothelial progenitor cell proliferation and mobilization. Here, we discuss the latest findings in this area and the clinical opportunities that they provide.

Inhibitor of DNA-binding protein 1 knockdown arrests the growth of colorectal cancer cells and suppresses hepatic metastasis in vivo

Inhibitor of DNA-binding protein 1 (ID1) is commonly abnormally overexpressed in colorectal cancer (CRC); yet, the functional significance of ID1 in the growth and invasive properties of CRC cells remains largely unclear. The present study investigated the effects of ID1 downregulation on the cell growth and metastatic features of CRC. Using lentiviral shRNA infection, stable ID1-knockdown (KD) HCT116 and SW620 cells, human metastatic CRC cell lines, were created. In vitro, the migration/invasion capacity of the ID1-KD CRC cells was assessed by a wound healing assay. The activities of MMP2 and MMP-9 were measured by gelatin zymography. The expression of CXC chemokine receptor 4 (CXCR4), PCNA and survivin were determined by immunoblot analysis and qRT-PCR. The effects of ID1 knockdown on tumor growth and hepatic metastasis were demonstrated by a xenograft study in mice. The results showed evident decreases in proliferation, migration and invasion and an increased apoptosis rate in the ID1-KD CRC cells. Similarly, ID1 knockdown significantly decreased mRNA and protein levels of PCNA, survivin, CXCR4, MMP2 and MMP9. Overexpression of CXCR4 antagonized the negative effect on the migration and invasion abilities of the ID1-KD cells. As compared with the control, ID1 knockdown prevented tumor growth and profoundly suppressed hepatic metastasis in vivo. The present study demonstrated the significance of ID1 in colon cancer progression, and its effect on tumor invasiveness and metastatic properties may be partly dependent on CXCR4.

The ID proteins: master regulators of cancer stem cells and tumour aggressiveness

Inhibitor of DNA binding (ID) proteins are transcriptional regulators that control the timing of cell fate determination and differentiation in stem and progenitor cells during normal development and adult life. ID genes are frequently deregulated in many types of human neoplasms, and they endow cancer cells with biological features that are hijacked from normal stem cells. The ability of ID proteins to function as central 'hubs' for the coordination of multiple cancer hallmarks has established these transcriptional regulators as therapeutic targets and biomarkers in specific types of human tumours.