IMperm: a fast and comprehensive IMmune Paired-End Reads Merger for sequencing data.

The adaptive immune receptor repertoire (AIRR), consisting of T- and B-cell receptors, is the core component of the immune system. The AIRR sequencing is commonly used in cancer immunotherapy and minimal residual disease (MRD) detection of leukemia and lymphoma. The AIRR is captured by primers and sequenced to yield paired-end (PE) reads. The PE reads could be merged into one sequence by the overlapped region between them. However, the wide range of AIRR data raises the difficulty, so a special tool is required. We developed a software package for IMmune PE reads merger of sequencing data, named IMperm. We used the k-mer-and-vote strategy to pin down the overlapped region rapidly. IMperm could handle all types of PE reads, eliminate adapter contamination and successfully merge low-quality and minor/non-overlapping reads. Compared with existing tools, IMperm performed better in both simulated and sequencing data. Notably, IMperm was well suited to processing the data of MRD detection in leukemia and lymphoma and detected 19 novel MRD clones in 14 patients with leukemia from previously published data. Additionally, IMperm can handle PE reads from other sources, and we demonstrated its effectiveness on two genomic and one cell-free deoxyribonucleic acid datasets. IMperm is implemented in the C programming language and consumes little runtime and memory. It is freely available at https://github.com/zhangwei2015/IMperm.

ScRNA-seq and bulk RNA-seq reveal the characteristics of ferroptosis and establish a risk signature in cholangiocarcinoma.

Ferroptosis is a recently discovered mode of cell death that inhibits tumor growth. Single-cell RNA sequencing (scRNA-seq) is a powerful tool for analyzing tumor heterogeneity and the immune microenvironment at the single-cell level. We used CIBERSORT to identify cellular immune scores and found that monocytes had significantly infiltrated and were correlated with prognosis in cholangiocarcinoma. scRNA-seq data were extracted from the Gene Expression Omnibus database, and the FindCluster() package was used for cell cluster analysis, which obtained 21 cell clusters, and there was increased TNFSF13B-TFRC intercellular communication between monocytes and cholangiocytes. A weighted correlation network analysis was performed with the WGCNA package to obtain monocyte-related gene modules. Univariate and multivariate Cox analyses were then performed to further establish the signature, and the reliability of the signature was assessed by receiver operating characteristic curve and decision curve analysis. A nomogram signature based on the Kaplan-Meier survival analysis was established. We found that the communication between monocytes and malignant cells in cholangiocarcinoma may be a regulatory factor of ferroptosis in cancer cells. The prognostic stratification system of the three-gene signature related to monocytes and ferroptosis can accurately assess the prognostic risk for cholangiocarcinoma.

Methodology established for the detection of circulating tumor DNA by hybridization capture.

Roche's AVENIO ctDNA analysis kits and bioinformatics analysis (the AVENIO system) are accessible to all NGS laboratories. We have developed an approach, namely the Sec-Seq system, and compared the accuracy, sensitivity, repeatability and economic cost between the AVENIO system and the Sec-Seq system. Both methods share the comparable accuracy and sensitivity in detecting the variant allele frequency of 0.0005, while the Sec-Seq system shows better accuracy in detecting the variant allele frequency of 0.001. Furthermore, the Sec-Seq system displays a much better detection sensitivity than the AVENIO system. The Sec-Seq system has satisfactory performance in detecting the rare genetic variants in ctDNA with lower economic cost compared with the AVENIO system.

AOSRV: Development and preliminary performance assessment of a new robotic system for autonomous percutaneous vertebroplasty.

BACKGROUND: Percutaneous vertebroplasty (PVP) is one of the most effective treatments for patients with vertebral fracture that need surgical treatment, and surgical robotics are promising tools to provide surgeons with improved precision, surgical efficiency and reduce radiation exposure. However, there are currently few robotics that are developed to help assist with PVP. METHODS: A new spinal surgical robotic system 'AOSRV' for autonomous vertebral puncture and bone cement injection was designed and customised in this study. To investigate its practical abilities and the advantages, we performed single-segment/double-segment PVP simulation surgeries on pig spinal specimens manually and using AOSRV. RESULTS: By contrast with the freehand group (FG) in single-segment (SS)/double-segment (DS) surgery, the robotic group (RG) was superior in the operation time (RGSS = 21.14 ± 4.11 min, FGSS = 33.17 ± 6.83 min; RGDS = 42.39 ± 7.31 min, FGDS = 62.86 ± 20.39 min), puncture adjustments (RGSS = 2.30 ± 1.77, FGSS = 14.86 ± 5.46; RGDS = 3.91 ± 1.76, FGDS = 20.00 ± 7.76), intraoperative fluoroscopies (RGSS = 4.10 ± 1.52, FGSS = 20.57 ± 5.44; RGDS = 7.82 ± 1.40, FGDS = 25.91 ± 7.23) and bone cement leakage rate (RGSS = 30%, FGSS = 71.4%; RGDS = 38.6%, FGDS = 83.3%). CONCLUSIONS: AOSRV was successfully developed and had a promising preliminary performance. An innovative attempt was made for the blank space of the autonomous vertebroplasty surgical robotics, and it may shed a light on more promising applications in the future.

Glomus tumor of uncertain malignant potential within the cervical spine: a case report.

The case report details the first glomus tumor (GT) of uncertain malignant potential within the cervical spine. The patient had been experiencing neck pain and numbness of the left side of her body for 3 months. Magnetic resonance imaging (MRI) revealed a lesion with the dimensions 22 mm × 11 mm in the left side of the intervertebral foramen and epidural of C1-5. When the patient appeared aggravating symptoms, we performed an emergency surgery to relieve the spinal cord compression resulting from the growing tumor. During the surgery, a grey-brown friable tumor was observed, and the tumor was located both outside and inside of the cervical spine. Morphological and immunohistochemical (IHC) analysis showed that the lesion was a globular tumor with uncertain malignant potential. After the surgery, the patient received adjuvant radiotherapy consisting of 58.9 Gy in 23 fractions postoperatively. The MRI at 4 months after the surgery showed a progression of the tumor, at which point the patient ceased treatment. GT of uncertain malignant potential within the cervical spine lacks specific clinical manifestations and reliable non-invasive means of examination, so its diagnosis depends on pathological biopsy and IHC examination. Surgical excision is the first treatment to relieve the symptoms of nerve compression. Further research of postoperative radiotherapy and chemotherapy is required to improve treatment options.

Surgical Resection of Solitary Bone Plasmacytoma of Atlas and Reconstruction with 3-Dimensional-Printed Titanium Patient-Specific Implant.

BACKGROUND: Solitary plasmacytoma of bone (SPB) is a rare malignancy of localized osseous lesion consisting of neoplastic monoclonal plasma cells. Recommended treatment of SPB includes a combination of surgery and radiation therapy. We present a rare case of SPB lesion in the atlas requiring surgical resection, followed by restoration of atlas stability with a custom 3-dimensional-printed (3DP) patient-specific implant (PSI). CASE DESCRIPTION: A 57-year-old man presented with severe neck pain. Assessment by radiographs, computed tomography, and magnetic resonance imaging was found to harbor a single osteolytic lesion at the C1 (atlas) vertebra. Diagnostic tumor screening returned negative results. Transoral biopsy suggested solitary plasmacytoma. Spinal instability was apparent-hence the decision for surgical intervention via the retropharyngeal external approach to resect the lesion. Atlas reconstruction and stabilization were achieved using a custom 3DP titanium PSI. Subsequent pathologic findings confirmed plasma cell infiltration of the atlas. Histologic evaluations and cytogenetic risk analysis indicated a non-high-risk SPB. The patient was given localized radiation therapy at 57 Gy in 27 fractions. Her neurologic complaints were subsequently relieved, and mobility was restored 7 days postoperatively. CONCLUSIONS: No consensus on the appropriate surgical approaches and perioperative strategies for spinal SPB exists. Surgical intervention is recommended when vertebral instability is evident, followed by radiation therapy to minimize local recurrence and/or progression to multiple myeloma. The use of 3D modeling for preoperative planning improves intraoperative accuracy and avoids iatrogenic injuries to vital anatomic structures. Customized 3DP-PSI to restore atlas stability is an effective option for the treatment of spinal SPBs.

Statistical analysis of mutant allele frequency level of circulating cell-free DNA and blood cells in healthy individuals.

Cell-free DNA (cfDNA) in plasma has emerged as a potential important biomarker in clinical diagnostics, particularly in cancer. However, somatic mutations are also commonly found in healthy individuals, which interfere with the effectiveness for cancer diagnostics. This study examined the background somatic mutations in white blood cells (WBC) and cfDNA in healthy controls based on sequencing data from 821 non-cancer individuals and several cancer samples with the aim of understanding the patterns of mutations detected in cfDNA. We determined the mutation allele frequencies in both WBC and cfDNA using a panel of 50 cancer-associated genes that covers 20 K-nucleotide region and ultra-deep sequencing with average depth >40000-fold. Our results showed that most of the mutations in cfDNA were highly correlated to WBC. We also observed that the NPM1 gene was the most frequently mutated gene in both WBC and cfDNA. Our study highlighted the importance of sequencing both cfDNA and WBC to improve the sensitivity and accuracy for calling cancer-related mutations from circulating tumour DNA, and shedded light on developing a strategy for early cancer diagnosis by cfDNA sequencing.

Soluble purified recombinant C2ORF40 protein inhibits tumor cell growth in vivo by decreasing telomerase activity in esophageal squamous cell carcinoma.

The chromosome 2 open reading frame 40 (C2ORF40) gene is a candidate tumor suppressor gene for a variety of tumors. Previous results by the present authors revealed that the C2ORF40 protein is a secreted protein. However, the exact biological function of secreted C2ORF40 protein in carcinogenesis has not been thoroughly investigated. In the present study, the signal peptide sequence of the C2ORF40 cDNA was initially removed to produce secreted recombinant human C2ORF40 protein (rhC2ORF40). Soluble rhC2ORF40 was successfully expressed and purified, which was evaluated for the first time, to the best of our knowledge, for tumor-suppressing function in vivo in esophageal cancer. The present results revealed that soluble purified rhC2ORF40 was concentrated with a purity of >95%. Furthermore, rhC2ORF40 inhibited esophageal cancer cell growth in vivo in a dose-dependent manner compared with a control group (P<0.05). In addition, the present study demonstrated for the first time that rhC2ORF40 decreased telomerase activity using telomeric repeat amplification protocol-enzyme-linked immunosorbent assay (P<0.05), without affecting the expression levels of telomerase-component RNA (P>0.05), as shown with polymerase chain reaction. Overall, the present results demonstrated that soluble rhC2ORF40 inhibited tumor cell growth in vivo by decreasing telomerase activity in esophageal squamous cell carcinoma. Therefore, soluble rhC2ORF40 with a high purity and biological activity may be a potential biological therapy drug for esophageal cancer.

Caveolin-1 affects tumor drug resistance in esophageal squamous cell carcinoma by regulating expressions of P-gp and MRP1.

Esophageal squamous cell carcinoma (ESCC) is the most common cancer in China, and multidrug resistance (MDR) remains one of the biggest problems in ESCC chemotherapy. In this study, we aimed to investigate the mechanism of Caveolin-1, an integral membrane protein, on regulating ESCC MDR. First, immunohistochemistry was used to check the protein expression of Caveolin-1, MDR-related protein of P-glycoprotein (P-gp), and multidrug resistance protein 1 (MRP1) in 84 pathologically characterized ESCC tissues, matched adjacent tumor, and adjacent normal-looking tissues. The results showed that Caveolin-1 expression level was elevated in ESCC tissues than that of matched adjacent tumor and adjacent normal-looking tissues (P < 0.05), and the expression of Caveolin-1 has close correlation with P-gp and MRP1 during tumor genesis of ESCC (P = 0.034, P = 0.009, respectively). Then, Caveolin-1 overexpression and knockdown were used to investigate its effect on expressions of P-gp and MRP1 in ESCC cell line Ec9706. The messenger RNA (mRNA) and protein expression levels of P-gp and MRP1 were checked by real-time quantitative reverse transcription-PCR (qRT-PCR) and Western blot (WB). The results showed that Caveolin-1 overexpression significantly promotes the mRNA and protein expression of MRP1 (P < 0.05), while almost has no effect on the mRNA and protein expression of P-gp (P > 0.05); Cavoelin-1 knockdown inhibits the mRNA and protein expressions of both P-gp and MRP1 (P < 0.05). The similar result was found in another ESCC cell line Eca109. So, it is concluded that Caveolin-1 affects ESCC MDR by regulating the expressions of P-gp and MRP1; therefore, it can be taken as a significant marker and target in tumor therapy.

Soluble purified recombinant C2ORF40 protein inhibits esophageal cancer cell proliferation by inducing cell cycle G1 phase block.

Chromosome 2 open reading frame 40 (C2ORF40) plays a significant role in numerous processes, including cell differentiation, senescence, apoptosis, inflammation and neuroendocrine hormone regulation. Moreover, C2ORF40 is a candidate tumor suppressor gene in a variety of tumors, and is closely associated with prognosis. Bioinformatics analysis has indicated that pro-C2ORF40 is a secreted protein with a signal peptide. Secreted C2ORF40 protein (sC2ORF40) exists in cancer cell medium. However, thus far, the exact biological function of sC2ORF40 in carcinogenesis has not been thoroughly researched. In the present study, the signal peptide sequence of the C2ORF40 complementary DNA was initially cut off to produce secreted recombinant human C2ORF40 protein (rhC2ORF40). The soluble rhC2ORF40 was expressed, purified and examined for tumor-suppressing function for the first time. The results revealed that the soluble purified rhC2ORF40 protein was concentrated with a purity of >95%. Furthermore, the rhC2ORF40 inhibited esophageal cancer cell proliferation in vitro (P<0.05) and caused cell cycle G1 phase block, as determined by flow cytometric analysis (P<0.05). Overall, the soluble rhC2ORF40 protein with high purity and biological activity was obtained, which suppressed esophageal cancer cells proliferation by inducing cell cycle G1 phase block in vitro. Therefore, the soluble rhC2ORF40 protein could be potential biological therapy drug for esophageal carcinoma.

Prognostic significance of tumor-infiltrating CD8⁺ or CD3⁺ T lymphocytes and interleukin-2 expression in radically resected non-small cell lung cancer.

BACKGROUND: Altered immunoresponse is associated with tumorigenesis and cancer progression. This study assessed the levels of tumor-infiltrating CD3 + or CD8 + T lymphocytes and interleukin-2 (IL-2) protein in radically resected non-small cell lung cancer (NSCLC) tissues to predict overall survival (OS) of the patients. METHODS: Paraffin-embedded tissue specimens from 129 NSCLC patients were retrospectively collected for immunostaining of CD8 + , CD3 + , and IL-2 expression. Clinicopathological and survival data were collected and analyzed using the Chi-squared test, Kaplan-Meier curves, and the log-rank test or the Cox regression model. RESULTS: The data showed a significant inverse association between CD8 + T lymphocyte levels and IL-2 expression (r = -0.927; P = 0.000) and between the levels of CD8 + and CD3 + T lymphocytes (r = -0.722; P = 0.000), but a positive association between CD3 + T lymphocyte levels and IL-2 expression (r = 0.781; P = 0.000) in NSCLC tissues. Furthermore, the levels of CD3 + and CD8 + T lymphocytes and IL-2 expression were associated with tumor stage (P = 0.023, 0.006, and 0.031, respectively) and the level of CD8 + T lymphocytes was associated with the patient gender (P = 0.024). In addition, the levels of CD8 + T lymphocytes were associated with an unfavorable 5-year OS, whereas patients with high levels of CD3 + T lymphocytes in tumor lesions and IL-2-expressing tumors had significantly better 5-year OS rates than patients with low levels. CONCLUSIONS: The levels of CD8 + T cells in tumor lesions and IL-2 expression were both independent predictors of OS for these NSCLC patients. Thus, the detection of tumor-infiltrating CD3 + or CD8 + T lymphocytes and IL-2 expression could be useful to predict the prognosis of radically resected NSCLC patients.

[A comparative analysis of the changes of transcriptome after fusion of esophageal cancer cells with human umbilical mesenchymal stem cells].

OBJECTIVE: To compare the transcriptome of esophageal cancer cells (EC9706), human mesenchymal stem cells (MSCs), and after fusion of esophageal cancer cells with MSCs, and to further study their different expression profiles and the changes of their signaling pathways. METHODS: We examined the gene expression profiles of these cells with transcriptome microarray using LIMMA package and several web-based applications, such as DAVID, ToppGene and MSigDB. The resulting sets of differentially expressed genes (DEGs) were comprehensively analyzed to identify the pathways and their changes after the cell fusion. RESULTS: A total of 4 548 significantly DEGs among the three cell lines were found by LIMMA. Three functional annotation web tools predicted that DNA damage repair, cell cycle arrest and apoptosis pathways were enriched. Total DEGs were mapped to the canonic pathways with KEGGanim which depicted that the core genes of DNA damage repair, cell cycle arrest and pro-apoptosis were up-regulated in fusion cells, and they mightbe combined to respond the fusion-induced damage stress. The up-regulation of suppressive factor DUSP6 might feedback inhibit the MAPK signaling pathway in the fusion cells, too. CONCLUSIONS: Transcriptome analysis suggests that hMSCs and EC9706 cell fusion may inhibit growth of EC cells by induction of pro-apoptotic signaling and DUSP6 negative feedback inhibition mechanism. In addition, the changes of immune regulation-related and differentiation-related genes indicate that the fusion cells inherited certain immune-suppressive function from the stem cells.

[Isolation and characterization of side population cells in human gastric cancer cell line BGC-823].

OBJECTIVE: Isolate and characterize the side population (SP) cells with potency of stem cells from human gastric carcinoma cell line BGC-823. METHODS: SP and non-SP cells were sorted from BGC-823 cells by fluorescence-activated cell sorting (FACS) using Hoechst33342 staining. The tumorigenic ability of the SP cells was assessed by in vivo transplantation into non-obese diabetic/severe combined immunodeficiency mice. RESULTS: SP cells were isolated from BGC-823 cells in a proportion of 0.9% to 2.1% with respect to the whole cell population. The colony formation assay showed that the colony formation rate of the SP cells was significantly higher than that of the non-SP cells (72.56% vs. 49.00%, P < 0.01). The drug sensitivity test showed that the SP cells showed stronger drug resistance to 5-Fu than the non-SP cells. The in vivo transplantation of SP cells in mice showed that the tumor weight was (0.176 ± 0.034) g, significantly higher than that of non-SP cells (0.045 ± 0.046) g (P < 0.01). CONCLUSIONS: The results of this study indicate the existence of cancer stem-like SP cells in the human gastric cancer line BGC-823 cells. Further characterization of this SP cell population may provide new insights for diagnosis and treatment of gastric cancer.

Fusion of human umbilical cord mesenchymal stem cells with esophageal carcinoma cells inhibits the tumorigenicity of esophageal carcinoma cells.

Prior studies on the biology and therapeutic application of human stem cells in human malignancies have reported mixed results. Some evidence shows the use of stem cell transplantation is an important tool in the treatment of several hematologic and non-hematologic malignancies while some others suggest both human stem cells and mature stromal cells can contribute to the development and growth of human malignancies. Aiming to provide more evidence on this controversial issue, we investigated the effect of cell fusion of mesenchymal stem cells with esophageal carcinoma cells on tumorigenesis. Results suggest that artificial fusion of human umbilical cord mesenchymal stem cells with esophageal carcinoma cells resulted in hybrids with declined cell growth, increased apoptosis and suppressed tumorigenicity. The comparison of gene expression profiles of human mesenchymal stem cells, esophageal carcinoma cells and hybrids indicated that fusion induced activation of apoptosis. Furthermore, the expression of DUSP6/MKP3 in MAPK pathway increased strikingly and the exogenous overexpression confirmed the growth suppression. Our results demonstrate fusion of human mesenchymal stem cells with esophageal carcinoma cells induced apoptosis and benign transdifferentiation rather than reprogramming to cancer stem cells.

Inhibition effects of all trans-retinoic acid on the growth and angiogenesis of esophageal squamous cell carcinoma in nude mice.

BACKGROUND: The potential application of retinoic acid receptor activators, such as all trans-retinoic acid (ATRA), for treating various cancers have been studied both pre-clinically and clinically. Whether ATRA has an anticancer effect on human esophageal squamous cancer cell (ESCC) is still unknown. We have explored the anticancer effect of ATRA in ESCC, and in this study, the effects of ATRA on levels and patterns of expression of the vascular endothelial growth factor (VEGF) signal transduction pathway in transplantable tumor growth of the human ESCC cell line, EC9706, in nude mice. METHODS: The animal model of the ESCC xenograft was made by subcutaneous implantation of tumor cells into nude mice. Reverse transcription-polymerase chain reaction (RT-PCR), Western blotting and immunohistochemical assays were used to detect the expression of the VEGF signal transduction pathway in ESCC xenograft tissues. RESULTS: Compared to the control group, the tumor inhibition rates in the low dose ATRA, high dose ATRA, and 5-FU groups were 83.21%, 88.32%, 91.02%, respectively. The protein and mRNA levels of VEGF were down-regulated after being treated with ATRA and 5-FU compared to the control group (P < 0.05). The study also revealed that ATRA specifically down-regulated VEGF and the component of the VEGF signal transduction pathway of CD31, CD34, and CD105 (component of the TGF-ß receptor) in ESCC xenograft tissues (P < 0.05). CONCLUSIONS: ATRA can significantly inhibit tumor growth and has anticancer effects on transplantable tumor growth of human ESCC cell line EC9706 in nude mice. These findings indicate that ATRA specifically down regulated VEGF and the components of VEGF signal transduction, which may be an important mechanism responsible for the neoangiogenesis inhibition of ESCC cells.

[Mechanism of loss of human esophageal cancer-related gene 4 (ECRG4) gene expression in esophageal squamous cell carcinoma cell line EC9706].

OBJECTIVE: To investigate the mechanism of loss of human esophageal cancer-related gene 4 (ECRG4) expression in esophageal squamous cell carcinoma (ESCC.) METHODS: PCR-SSCP and DNA sequencing analysis were used to detect the mutation of ECRG4 exons in esophageal cancer and matched adjacent normal tissues of 80 patients. DNA bisulfite-modifying ssPCR sequencing assay was used to examine the methylation status of ECRG4 promoter in human esophageal squamous cell carcinoma EC9706 cells. The re-expression of ECRG4 mRNA was examined by RT-PCR in EC9706 cells, after treatment with either demethylation drug 5-aza-2'-deoxycytidine or arsenic trioxide. RESULTS: No mutation in the four ECRG4 exons was found in all the ESCC and matched normal adjacent tissues. RT-PCR showed that 11 of 16 CpG islands of ECRG4 promoter were hypermethylated, while ECRG4 mRNA expression level was undetectable in the EC9706 cells. The ECRG4 mRNA was re-expressed after treatment with either demethylation drug 5-aza-2'-deoxycytidine or arsenic trioxide. CONCLUSION: The epigenetic mechanism of methylation is a reason of loss of ECRG4 gene expression in the ESCC cell line EC9706.

[Expression of IGF-1R in esophageal squamous cell carcinoma and the effect of its silencing by siRNA on the proliferation of esophageal cancer EC9706 cells in vitro].

OBJECTIVE: To explore the correlation of IGF-1R expression with clinical features of esophageal squamous cell carcinoma (ESCC) and to investigate the effect of silencing IGF-1R by siRNA on the proliferation of esophageal cancer cell line EC9706 cells. METHODS: Immunohistochemistry was used to detect the expresion of IGF-1R in 80 specimens of ESCC and 18 specimens of normal esophageal mucosa. IGF-1R siRNA was transfected into esophageal squamous cell carcinoma EC9706 cells, and the effect of RNAi was assessed by Western blot. The proliferation of EC9706 cells was determined by drawing growth curve, MTT assay and plate colony-forming assay. RESULTS: The total and strong positive rates of IGF-1R expression were 86.3% and 51.3% in ESCC, and 61.1% and 11.1% in normal esophageal epithelium, respectively. The total and strong positive rates of IGF-1R expression in patients with lymph node metastasis were 94.4% and 74.1%, significantly higher than 69.2% and 3.9%, respectively, in those without lymph node metastasis (P<0.01). A significantly higher IGF-1R expression was associated with lower histological grade (P<0.05). The total and strong rates of IGF-1R expression in 39 patients of stages III and IV were 97.4% and 71.8% , significantly higher than the 75.6% and 31.7%, respectively, in 41 cases of stages I and II (P<0.01). IGF-1R RNAi significantly inhibited IGF-1R expression and the growth of EC9706 cells. The clone formation rate of RNAi-IGF-1R transfected cells was 19.1%, significantly lower than that of 52.3% in non-transfected cells and 49.0% in empty vector-transfected EC9706 cells (P<0.05). CONCLUSIONS: The overexpression of IGF-1R is colerated with lymph node metastasis, differentiation and clinical stage. Down-regulation of IGF-1R can inhibit the proliferation of esophageal cancer EC9706 cells in vitro.

[The relationship between retinoic acid receptor-ß expression and chemotherapy response in esophageal squamous cell carcinoma].

OBJECTIVE: To observe the relationship between expression of retinoic acid receptor-ß(RAR-ß) in esophageal squamous cell carcinoma (ESCC) and chemotherapy response. METHODS: Fifty-two cases advanced ESCC patients treated by DDP and 5-FU, DDP 80 mg/m(2), divided into 5 days; 5-FU 375 mg/m(2), d1-5. Immunohistochemistry was used to examine the expression of RAR-ß in ESCC. Fifty cases normal esophageal tissue were used as controls. RESULTS: RAR-ß immunoreactivity was recognized in both cytoplasm and nucleus, RAR-ß positive rate was lower in ESCC compared with normal tissue (61.5% vs 92%, P < 0.05). The 52 cases ESCC patients were treated 228 chemotherapy cycles, the overall response rate (OR) was 71.2%. The OR in RAR-ß positive patients was 84.4% (27/32), significant higher than RAR-ß negative patients 50.0% (10/20) (P < 0.05). The time-to-progression (TTP) for RAR-ß positive patients was 5.9 months, the median survival period was 12.1 months, 2 years survival rate was 56.7%; whereas TTP for RAR-ß negative patients was 2.1 months, the median survival period was 5.8 months, 2 years survival rate was 32.9%. There was significant difference between the 2 groups (P < 0.05). CONCLUSION: RAR-ß protein expression by immunohistochemistry may be a useful indicator to predict the chemotherapy response and clinical outcome for ESCC, meanwhile it may be an avenue for target therapy.

[Tumor-suppressing function of human esophageal cancer related gene 4 in esophageal squamous cell carcinoma].

OBJECTIVE: To investigate the tumor-suppressing function of human esophageal cancer related gene 4 (ECRG4) in esophageal squamous cell carcinoma (ESCC). METHODS: The recombinant plasmid pcDNA3.1-ECRG4 with ECRG4 open reading frame was constructed. The EC9706 cell was transfected with either pcDNA3.1 or pcDNA3.1-ECRG4. And the effects of ECRG4 on tumor cell were examined by in vivo assays of cell proliferation, adhesion, migration, invasion and tumor growth. The expression levels of P53 and P21 proteins were detected in EC9706 cell with transfection of ECRG4 gene by Western blotting. RESULTS: The final tumor volume and weight in ECRG4 transfection group were (264±43) mm3 and (0.39±0.09) g, versus (464±128) mm3 and (0.76±0.13) g in control group (both P<0.05). And the capacities of tumor cells adhesion, migration and invasion decreased in ECRG4 transfection group versus that in control group (all P>0.05). Furthermore, the expression levels of P53 and P21 proteins were higher in ECRG4 transfection group than those in control group (100.00±3.87, 35.71±2.36 vs 16.6±1.92, 1.09±0.11, both P<0.05). CONCLUSION: As a novel candidate tumor suppressor in ESCC, ECRG4 may induce the up-regulation of p21 protein through p53 pathway to inhibit tumor growth in ESCC.