Molecular characterisation and expression analysis of SEREX-defined antigen NUCB2 in gastric epithelium, gastritis and gastric cancer

Nucleobindin 2 inhibits senescence in gastric carcinoma

Here, we focused on the role of Nucleobindin 2 (NUCB2), a multifunctional protein, in gastric carcinoma (GC) progression. NUCB2 expression was investigated in 150 GC cases (20 non-invasive (pT1) and 130 invasive (pT2/pT3/pT4) tumors) by immunohistochemistry (IHC), and in situ hybridization for detection of the mRNA in 21 cases. Using GC cell lines, we determined whether NUCB2 expression was associated with specific cellular phenotypes. In GC clinical samples, NUCB2 was transcriptionally upregulated when compared to normal tissues. High NUCB2 expression was associated with clinicopathological factors including deep tumor invasion, lymphovascular invasion, lymph node metastasis, and advanced clinical stages, and was a significant independent predictor of unfavorable progression-free survival in 150 non-invasive and invasive GC patients. Similar findings were also evident in 72 invasive GC cases in which patients received post-operative chemotherapy, but not in 58 invasive tumors from patients who did not receive the chemotherapy. In cell lines, NUCB2 knockout inhibited proliferation, susceptibility to apoptosis, and migration capability by inducting cellular senescence; this was consistent with higher proliferation and apoptotic indices in the NUCB2 IHC-high compared to NUCB2 IHC-low GC cases. NUCB2-dependent inhibition of senescence in GC engenders aggressive tumor behavior by modulating proliferation, apoptosis, and migration.

NUCB2: roles in physiology and pathology

Nucleobindin2 (NUCB2) is a member of nucleobindin family which was first found in the nucleus of the hypothalamus, and had a relationship in diet and energy homeostasis. Its location in normal tissues such as stomach and islet further confirms that it plays a vital role in the regulation of physiological functions of the body. Besides, NUCB2 participates in tumorigenesis through activating various signal-pathways, more and more studies indicate that NUCB2 might impact tumor progression by promoting or inhibiting proliferation, apoptosis, autophagy, metastasis, and invasion of tumor cells. In this review, we comprehensively stated NUCB2's expression and functions, and introduced the role of NUCB2 in physiology and pathology and its mechanism. What is more, pointed out the potential direction of future research.

circ_001504 promotes the development of renal cell carcinoma by sponging microRNA-149 to increase NUCB2

Renal cell carcinoma (RCC) accounts for over 90% of primary renal tumors in adults. Although treatment approaches have steadily improved over the years, the prognosis outcome remains poor. With the aim of developing novel targets for RCC treatment, we explored the role of the circular RNA (circRNA) circ_001504 in the progression of RCC. We initially detected the expression of circ_001504 and microRNA (miRNA)-149 in RCC tissues and cells. RT-qPCR results showed that circ_001504 was highly expressed in RCC tissues, whereas miR-149 was poorly expressed. Interestingly, downregulation of circ_001504 suppressed malignant phenotypes in RCC cells, and upregulation of miR-149 exerted a similar effect. Bioinformatics analysis suggested potential binding sites between circ_001504 and miR-149, verified by a dual-luciferase reporter gene assay. Next, we identified nucleobindin 2 (NUCB2), a calcium-binding protein, as a target gene of miR-149. Furthermore, our data suggested that circ_001504 might serve as a competing endogenous RNA of miR-149, serving to elevate the expression of NUCB2. The silencing of circ_001504 resulted in decreased NUCB2 expression, which could be reversed by miR-149 inhibition. In addition, in vivo experiments demonstrated that circ_001504 depletion could suppress tumor growth in an established mouse RCC model. Collectively, reduced expression of circ_001504 lowered NUCB2 expression by sponging miR-149, thereby attenuating RCC progression, providing insight into circ_001504/miR-149/NUCB2 feedback loop into RCC treatment.

Nucleobindin 2 expression is an independent prognostic factor for bladder cancer

Nucleobindin 2 (NUCB2) has been reported to play an important role in both tumorigenesis and cancer progression. This study aimed to examine the clinical significance of NUCB2 expression urothelial carcinoma of the bladder (UCB).The expression level of NUCB2 and its correlation with clinicopathological parameters was analyzed in 225 UCB tissues by immunohistochemistry. Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between NUCB2 expression and the prognosis of UCB patients. High NUCB2 expression of UCB patients significantly correlated with aggressive clinicopathological features. Patients with high NUCB2 had shorter overall survival and recurrence-free survival in Kaplan-Meier survival curve (P = .018 and P = .001, respectively).Our results show that high expression of NUCB2 associated with aggressive clinicopathological feature and predicted unfavorable prognosis in patients with UCB might serve as feasible biomarker for clinical outcome of UCB patients after surgery and potential therapeutic target in the future.

High expression of nucleobindin 2 is associated with poor prognosis in gastric cancer

Nucleobindin 2 has been reported that its high expression is associated with poor outcome and promotes cell migration and lymph node metastasis in breast cancer, colon cancer, and prostate cancer. However, we aimed to investigate the nucleobindin 2 expression in gastric cancer tissues and adjacent non-tumor tissues and its potential relevance to clinicopathological factors and prognosis using immunohistochemical analysis. In our study, nucleobindin 2 level in gastric cancer tissues was higher than in non-tumor tissues. A high expression of nucleobindin 2 is significantly associated with tumor depth, lymph node metastasis, lymphatic invasion, venous invasion, and clinical stage. Furthermore, the expression level of nucleobindin 2 protein was independent predictor of progression-free survival. In summary, nucleobindin 2 might play a crucial role in gastric cancer development and could serve as an independent predictor of prognosis of gastric cancer patients.

Nucleobindin 2 (NUCB2) in human endometrial carcinoma: a potent prognostic factor associated with cell proliferation and migration

Nucleobindin 2 (NUCB2) is a multifunctional protein containing several functional domains, and associated with wide variety of biological process such as food intake and energy homeostasis. Recently, NUCB2 has been implicated in not only normal human tissues but also some kinds of human malignancies. However, its clinical and/or biological significance has largely remained unknown in endometrial carcinomas. We therefore immunolocalized NUCB2 protein in 87 endometrial carcinoma tissues and examined its clinical significance. NUCB2 immunoreactivity was detected in 19 out of 87 (22%) of endometrial carcinoma cases examined, and positively correlated with Ki67 labeling index, while there was no significant correlation between NUCB2 and stage, histological grade, and progesterone receptor status. Furthermore, NUCB2 immunoreactivity was significantly correlated with increased risk of recurrence and worse clinical outcome regardless of stage or histological grade. Subsequent multivariate analyses did reveal that NUCB2 immunoreactivity was an independent prognostic factor for both disease-free survival and endometrial cancer specific survival. In vitro experiments demonstrated that knockdown of NUCB2 using specific siRNA for NUCB2 significantly impaired cell proliferation and migration of the endometrial carcinoma cell lines, Ishikawa and Sawano cells, and that nesfatin-1 treatment significantly promoted cell proliferation and migration in Ishikawa cells. These findings possibly suggested that NUCB2 and/or nesfatin-1 had pivotal roles in the progression of endometrial carcinomas. Immunohistochemical NUCB2 status may therefore serve as a potent biomarker for endometrial carcinomas.

Serological proteome analysis of dogs with breast cancer unveils common serum biomarkers with human counterparts

Canine mammary tumor is being touted as a model for investigating the human breast cancer. Breast cancer of the both species has similar biological behavior, histopathologic characteristics, and metastatic pattern. In this study, we used the serological proteome analysis to detect autoantigens that elicit a humoral response in dogs with mammary tumor in order to identify serum biomarkers with potential usefulness as diagnostic markers and to better understand molecular mechanisms underlying canine breast cancer development. Protein extract from a cell line was subject to 2DE followed by Western blotting using sera from 15 dogs with mammary tumor and sera from 15 healthy control dogs. Immunoreactive autoantigens were subsequently identified by the MALDI-TOF MS. Four autoantigens, including manganese-superoxide dismutase, triose phosphate isomerase, alpha-enolase, and phosphoglycerate mutase1, with significantly higher immunoreactivity in the tumor samples than in the normal samples were identified as biomarker candidates. Immunohistochemistry and Western blotting revealed higher expression of these biomarkers in the malignant tumors than in the normal or benign tumors. The autoantigens found in this study have been reported to elicit autoantibody response in the human breast cancer, indicating the similarity of breast cancer proteome profile in dogs with that in human beings.

Prognostication of prostate cancer based on NUCB2 protein assessment: NUCB2 in prostate cancer

BACKGROUND

Nucleobindin 2 (NUCB2) protein, a novel oncoprotein, is overexpressed in breast cancer. To date, there have been no published data regarding the role of NUCB2 protein expression in prostate cancer (PCa). Therefore, this study was performed to investigate the correlations between NUCB2 protein expression and prognosis in patients with PCa.

METHODS

Through immunohistochemistry, NUCB2 protein expression was evaluated in 60 benign prostatic hyperplasia (BPH) specimens and 180 PCa specimens. The correlation of NUCB2 protein expression with clinicopathological parameters was assessed using χ2 analysis. Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between NUCB2 protein expression and prognosis of PCa patients.

RESULTS

The immunohistochemistry results showed that the expression level of NUCB2 in PCa cases was significantly higher than that in BPH tissues (P < 0.001). Moreover, statistical analysis also showed that high NUCB2 protein expression was positively related to seminal vesicle invasion, lymph node metastasis, angiolymphatic invasion, higher Gleason score, biochemical recurrence (BCR), and higher preoperative prostate-specific antigen (PSA). Furthermore, it was also shown that patients with high NUCB2 protein expression had significantly poorer overall survival and BCR- free survival compared with patients with low expression of NUCB2 protein. Multivariate Cox regression analysis revealed that high NUCB2 protein expression level was an independent prognostic factor for overall survival and BCR-free survival of patients with PCa.

CONCLUSIONS

NUCB2 protein expression showed a strong association with the potencies of BCR and progression of PCa, and that may be applied as a novel biomarker for the prediction of BCR, and helpful for improving the diagnosis, prognosis and treatment of PCa.

Clinical significance of NUCB2 mRNA expression in prostate cancer

Background

Nucleobindin 2 (NUCB2) abnormal expression has been reported in gastric cancer and breast cancer. However, the role of NUCB2 in prostate cancer (PCa) remains unclear. The aim of the present study was to investigate the NUCB2 expression in PCa tissues and adjacent non-cancerous tissues and its potential relevance to clinicopathological variables and prognosis.

Methods

NUCB2 mRNA expression was determined by real-time quantitative real time reverse transcriptase polymerase chain reaction in 180 pairs of fresh frozen PCa tissues and corresponding non-cancerous tissues. Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between NUCB2 expression and prognosis of PCa patients.

Results

Our results showed that the expression level of NUCB2 mRNA in PCa tissues was significantly higher than those in non-cancerous tissues. Our results indicated that the high expression of NUCB2 in PCa was associated with lymph node metastasis, preoperative PSA, Gleason score, and angiolymphatic invasion. Kaplan–Meier survival analysis showed that patients with high NUCB2 expression have shorter biochemical recurrence (BCR)-free survival time compared to patients with low NUCB2 expression. Multivariate analysis revealed that NUCB2 expression was an independent predictor of BCR-free survival.

Conclusions

NUCB2 might play a positive role in PCa development and could serve as an independent predictor of BCR-free survival.

Tumor-associated autoantibody signature for the early detection of gastric cancer

Autoantibodies against tumor-associated antigens are very attractive biomarkers for the development of noninvasive serological tests for the early detection of cancer because of their specificity and stability in the sera. In our study, we applied T7 phage display-based serological analysis of recombinant cDNA expression libraries technique to identify a representative set of antigens eliciting humoral responses in patients with gastric cancer (GC), produced phage-antigen microarrays and exploited them for the survey of autoantibody repertoire in patients with GC and inflammatory diseases. We developed procedures for data normalization and cutoff determination to define sero-positive signals and ranked them by the signal intensity and frequency of reactivity. To identify autoantibodies with the highest diagnostic value, a 1,150-feature microarray was tested with sera from 100 patients with GC and 100 cancer-free controls, and then the top-ranked 86 antigens were used for the production of focused array that was tested with an independent validation set comprising serum samples from 235 patients with GC, 154 patients with peptic ulcer and gastritis and 213 healthy controls. The receiver operating characteristic curve analysis showed that 45-autoantibody signature could discriminate GC and healthy controls with area under the curve (AUC) of 0.79 (59% sensitivity and 90% specificity), GC and peptic ulcer with AUC of 0.76 and GC and gastritis with AUC of 0.64. Moreover, it could detect early GC with equal sensitivity than advanced GC. Interestingly, the autoantibody production did not correlate with histological type, H. pylori status, grade, localization and size of the primary tumor, whereas it appeared to be associated with the metastatic disease.

Nucleobindin 2 in human breast carcinoma as a potent prognostic factor

It is well-known that estrogens immensely contribute to the progression of human breast carcinoma, but their detailed molecular mechanisms remain largely unclear. In this study, we identified nucleobindin 2 (NUCB2) as a gene associated with recurrence based on microarray data of estrogen receptor (ER)-positive breast carcinoma cases (n = 10), and subsequent in vitro study showed that NUCB2 expression was upregulated by estradiol in ER-positive MCF-7 cells. However, NUCB2 has not yet been examined in breast carcinoma, and its significance remains unknown. Therefore, we further examined the biological functions of NUCB2 in breast carcinoma using immunohistochemistry and in vitro studies. NUCB2 immunoreactivity was detected in carcinoma cells in 77 of 161 (48%) breast cancer cases, and positively associated with lymph node metastasis and ER status of the patients. In addition, NUCB2 status was significantly associated with an increased risk of recurrence and adverse clinical outcome of the patients using both univariate and multivariate analyses. Results of siRNA transfection experiments showed that NUCB2 significantly increased cell proliferation, and migration and invasion properties in both MCF-7 and ER-negative SK-BR-3 cells. These results suggest that NUCB2 is upregulated by estrogens and plays an important role, especially in the process of metastasis, in breast carcinomas. NUCB2 status is considered a potent prognostic factor in human breast cancer.