Decreased expression of Siglec-8 associates with poor prognosis in patients with gastric cancer after surgical resection

Immunopositivity for Siglec-15 in gastric cancer and its association with clinical and pathological parameters

The sialic acid-binding immunoglobulin-type lectin Siglec-15 is a promising target for cancer immunotherapy in several tumor types. The present study aimed to investigate Siglec-15 expression in gastric cancer (GC) patient tissues and to evaluate its clinical value. Siglec-15 expression was evaluated by immunohistochemistry in 71 patients. Siglec-15 staining was observed in tumor cells of 53 (74.64%) patients, with significant association with histologic classification and angiolymphatic invasion (p<0.05). Immunohistochemistry analysis also detected Siglec-15 in tumor-associated stroma cells (macrophages/myeloid cells). There was no significant association with outcome parameters. Siglec-15 expression in well differentiated histological GC tissues and in the tumor microenvironment are potential targets to be further investigated as a novel prognostic factor for GC.

First Evidence for a Role of Siglec-8 in Breast Cancer

Sialic acid-binding immunoglobulin-like lectins (Siglecs) are involved in various immune cell-mediated diseases. Their role in cancer is poorly investigated, and research focusses on Siglec-expression on immune cells interacting with tumor cells. This study evaluates the role of Siglec-8 in breast cancer (BC). Siglec-8 expression was analyzed immunohistochemically on 235 primary BC cases and was correlated with clinical and pathological parameters and outcome. Cell culture experiments were performed with various BC cell lines. Siglec-8 was expressed in 215 BC cases and expression was lowest in triple-negative BC. It correlated with estrogen receptor-status, grading and the prognostic factors galectin (Gal)-7 and tumor-associated mucin-1 (TA-MUC1). However, Gal-7 and TA-MUC1 were only prognosticators for clinical outcome in the cohort expressing high (Immunoreactivity score IRS > 3) Siglec-8 levels but not in the low-expressing cohort. Siglec-8 knockdown led to a significantly reduced Gal-7 expression in MCF7 cells. All BC cell lines expressed low Siglec-8-levels, that could be elevated in MCF7 by Peroxisome proliferator-activated receptor (PPARγ)-stimulation. This study demonstrates that Siglec-8 is expressed in BC cells and correlates with known clinical and prognostic parameters. It is probably associated with Gal-7 and TA-MUC1 and might be regulated via PPARγ. Further analyses focusing on functional associations will clarify Siglec-8’s eligibility as a possible therapeutic target.

Integrative Analysis of Siglec-15 mRNA in Human Cancers Based on Data Mining

Objective: Cancer is expected to be the leading cause of death worldwide within the 21st century and is the single most important obstacle to extending life expectancy. Unfortunately, the most effective approach to combating cancers remains a complex and unsolved problem. Siglec-15 is a member of the Siglec family and plays a conserved regulatory role in the immune system of vertebrates. Previous studies on Siglec-15 have focused on its function in osteoclast regulation. The purpose of this study was to explore the significance of Siglec-15 mRNA in human cancer mainly based on information obtained from online databases. Method: Data were collected from several online databases. Serial analysis of gene expression (SAGE) and Virtual Northern, UALCAN Database Analysis, Catalog of Somatic Mutations in Cancer (COSMIC) analysis, the cBio cancer genomics portal, Cancer Regulome tools and data, Kaplan-Meier Plotter Analysis and the UCSC Xena website were used to analyze the data. Results: Compared with normal tissues, Siglec-15 up-regulation was widely observed in tuomrs. Differences in Siglec-15 expression were associated with different prognoses. Siglec-15 mutations are widely observed in tumors and interact with different genes in different cancer types. Conclusion: Siglec-15 is a potential target for the expansion of cancer immunotherapy.

Clinical significance of serum total oxidant/antioxidant status in patients with operable and advanced gastric cancer

Purpose

Oxidative stress was significantly associated with the development of malignancies. The purpose of this study was to evaluate the significance of serum total oxidant/antioxidant status in operable advanced gastric cancer patients.

Materials and methods

A total of 284 patients who underwent curative resection for primary stage III gastric cancer were enrolled. Total oxidant status, total antioxidant status, and oxidative stress index (OSI) were evaluated within 24 hours before surgery, and compared with 120 healthy donors. The correlation between the OSI and survival outcome was analyzed by the Kaplan–Meier method with log-rank test and Cox’s regression methods, respectively.

Results

Mean OSI of gastric cancer patients was higher than healthy controls (1.41±0.96 vs 0.78±0.42, P<0.001). All patients were stratified into two groups using the optimal cutoff value (1.42) of OSI using a sensitivity of 94.1% and a specificity of 64.0% as optimal conditions from receiver operating curve analysis. Patients with an OSI ≥1.42 had poorer mean overall survival (45.6 vs 29.8 months, P=0.022) and mean recurrence-free survival (43.3 vs 28.1 months, P=0.011) than patients with an OSI <1.42 in univariate analysis, and OSI was also confirmed as an independent predictor for survival for gastric cancer in multivariate analysis (hazard ratio, 0.541; 95% CI: 0.127–1.102; P=0.01).

Conclusion

Preoperative OSI can be considered as an independent prognostic factor for operable and advanced gastric cancer.

Significance of preoperative ischemia- modified albumin in operable and advanced gastric cancer

BACKGROUND

Oxidative stress plays an important role in promoting proliferation and metastases of cancer, which can be represented by ischemia-modified albumin (IMA). The purpose of this study was to evaluate serum IMA level in patients with operable advanced gastric cancer and analyze its prognostic significance.

MATERIALS AND METHODS

A total of 274 patients with primary stage III gastric cancer underwent curative operation were enrolled in this study. Serum IMA level was measured within 24 hours before surgery, comparing with 112 healthy donors. The correlation between serum IMA level and survival outcome was analyzed by the Kaplan-Meier with Log-Rank test and Cox's regression methods, respectively.

RESULTS

Serum IMA level from gastric cancer was higher than healthy control (0.41 ± 0.12 VS 0.23 ± 0.08; P< 0.001). Finally, 173 and 181 patients out of all 274 patients studied had died and recurrent, respectively. All patients were stratified into two groups using the optimal cutoff value (0.45) of IMA level using a sensitivity of 92.5% and a specificity of 65.2% as optimal conditions from receiver operating curve analysis. Patients with a IMA ⩾ 0.45 had poorer mean overall survival (44.68 months VS 30.94 months, P= 0.010) and mean recurrence free survival (42.36 months VS 28.82 months, p= 0.01) than patients with a IMA < 0.45 in univariate analysis and IMA also been confirmed as independent predictor for survival for GC patients in multivariate analysis (OR, 0.731; 95% CI: 0.329-1.282; p= 0.023).

CONCLUSIONS

Serum IMA level can be considered as an independent prognostic factor for operable and advanced gastric cancer.

Association of O6-Methylguanine-DNA Methyltransferase Protein Expression With Postoperative Prognosis and Adjuvant Chemotherapeutic Benefits Among Patients With Stage II or III Gastric Cancer

IMPORTANCE

Loss of O6-methylguanine-DNA methyltransferase (MGMT) protein expression has been reported in several malignant tumors and predicts dismal survival outcomes. In gastric cancer, existing studies on this topic are limited and the association between MGMT and fluorouracil-based adjuvant chemotherapy remains obscure.

OBJECTIVE

To investigate the postoperative prognostic significance of MGMT in patients with resectable gastric cancer and its responsiveness to fluorouracil-based adjuvant chemotherapy.

DESIGN, SETTING, AND PARTICIPANTS

This study recruited 445 consecutive patients with resectable gastric cancer who underwent radical gastrectomy between August 1, 2007, and December 30, 2008, at Zhongshan Hospital at Fudan University in Shanghai, China. Patients were randomly divided into a discovery data set (n = 200) and a validation data set (n = 245), and the range of follow-up time was from 2 to 76 months for the discovery group and 2 to 79 months for the validation group. The immunoreactivity for MGMT in cancer cells was reviewed under a light microscope by 2 pathologists who were blinded to the clinicopathological data. The association of MGMT expression with clinicopathological characteristics and measures and prognosis was inspected. Data and specimens were collected from patients from the date of surgery to April 25, 2014. Data analysis took place from May 9, 2016, to July 15, 2016.

MAIN OUTCOMES AND MEASURES

Estimates of overall survival on the basis of MGMT expression and hazard ratio (HR) for estimates of overall mortality risk.

RESULTS

Of the 445 patients included in the study, 315 (70.8%) were men, and the mean (SD) age of all patients was 60 (12) years. Positive expression of MGMT indicated better overall survival for patients with stage II or III gastric cancer in both the discovery data set (HR, 0.52; 95% CI, 0.32-0.84; P = .003) and the validation data set (HR, 0.63; 95% CI, 0.43-0.93; P = .01). Multivariate analysis identified MGMT expression and TNM stage as 2 independent prognostic factors for overall survival. In stage II disease, the benefit from fluorouracil-based adjuvant chemotherapy was superior among MGMT-positive patients (HR, 0.35; 95% CI, 0.13-0.95; P = .007 for interaction) compared with MGMT-negative patients.

CONCLUSIONS AND RELEVANCE

Positive expression of MGMT in gastric cancer was identified as an independent, favorable prognostic factor. Incorporating MGMT expression into the current TNM staging system could lead to better prognostic accuracy. These findings should be confirmed within the framework of randomized clinical trials associated with genomic DNA sequencing studies.

Enhancement of Siglec-8 expression predicts adverse prognosis in patients with clear cell renal cell carcinoma

PURPOSE

Sialic acid-binding immunoglobulin-like lectins (siglecs) family has important functions in tumor progression. The purpose of our study is to figure out the correlation between the expression level of Siglec-8 and prognosis of patients with clear cell renal cell carcinoma (ccRCC), and then to predict the overall survival (OS) via a novel nomogram.

MATERIALS AND METHODS

A group of patients (n = 267) histologically diagnosed with ccRCC from Zhongshan Hospital were included into our study. Immunohistochemistry of Siglec-8 was performed in the tissue microarray, and the staining intensity was divided into high/low according to the median value of the H-score grading. Survival analyses including Kaplan-Meier analyses and Cox regression analyses were performed to evaluate the association between Siglec-8 expression and the survival of patients in different risk groups. Stage, size, grade, and necrosis score and University of California Los Angeles Integrated Staging System score were used in the risk stratification. A nomogram incorporating Siglec-8 and several other clinical parameters was plotted for predicting the 5-year and 8-year OS.

RESULTS

Siglec-8 was observed dominantly on the membrane of tumor cells. The enhanced expression level of Siglec-8 had significant correlation with adverse overall and disease-free survival of patients (P<0.0001 and P = 0.0186, respectively). The association was more significant in patients with lower risk. Cox regression analyses defined Siglec-8 as an independent prognostic factor of OS (P<0.001 for univariate analysis, P = 0.003 for multivariate analysis). The new nomogram integrating Siglec-8 with several traditional prognostic factors proved to be more accurate than conventional prognostic system using tumor node metastasis stage only (Harrell c-index: 0.801, 95% CI: 0.755-0.847 vs. 0.717, 95% CI: 0.662-0.772).

CONCLUSION

Our study has found that the elevated expression level of Siglec-8 was correlated with poor prognosis of patients with ccRCC. Siglec-8, incorporation with other clinical parameters, could perform better in prediction of patients׳ OS.