Correlation of Aurora-A expression with the effect of chemoradiation therapy on esophageal squamous cell carcinoma

BACKGROUND

Chemoradiation therapy (CRT) is one of the most useful treatments for esophageal squamous cell carcinoma (ESCC). However, because some patients respond well to CRT and others do not, it is important to be able to predict response to CRT before beginning treatment by using markers. Aurora-A encodes a cell cycle regulated serine/threonine kinase that has essential functions in centrosome maturation and chromosome segregation. In this study, we investigated the relationship between the expression of Aurora-A and the response to CRT in patients with ESCC.

METHODS

We immunohistochemically investigated the expression of Aurora-A in biopsy specimens of untreated primary tumors of 78 patients with ESCC and determined the relationship between Aurora-A levels and patient responses to CRT, which consisted of 5-fluorouracil plus cisplatin and 40 Gy of radiation.

RESULTS

Tumors were judged as Aurora-A positive when more than 10% of the cancer cells displayed a distinct positive nuclear anti-Aurora-A immunoreaction by immunohistochemical evaluation. The tumors of 46 of 78 patients (58.9%) displayed positive expression of Aurora-A. In terms of clinical response the percentage of patients showing complete response (CR), incomplete response/stable disease of primary lesion (IR/SD), and progressive disease (PD) was 19.2, 69.2, and 11.5%, respectively. In terms of histological response the tumor grade of the 41 patients who underwent surgery was as follows: grade 1, 48.8%; grade 2, 29.2%; grade 3, 22.0%. CRT was effective for patients who had Aurora-A (+) tumors (clinically: P = 0.0003, histologically: P = 0.036).

CONCLUSIONS

Our results suggest that Aurora-A expression in biopsy specimens of primary tumors is associated with CRT efficacy in patients with ESCC. Assessment of Aurora-A expression in biopsy specimens maybe useful for regarding the potential utility of CRT therapy for patients with ESCC before treatment.

Clinicopathological significance of nuclear factor (erythroid-2)-related factor 2 (Nrf2) expression in gastric cancer

Background

The transcription factor nuclear factor (erythroid-2)–related factor 2 (Nrf2) was originally identified as a critical regulator of intracellular anti-oxidants and of phase II detoxification enzymes through its transcriptional up-regulation of many anti-oxidant response element (ARE)-containing genes. Nrf2 protects not only normal cells but also cancer cells from cellular stress, and enhances cancer cell survival. Some studies have shown that Nrf2 expression in cancer patients has clinical significance. However, there has been no comprehensive analysis of the nuclear expression level of Nrf2 in gastrointestinal cancer cells. In this study we aimed to immunohistochemically evaluate the expression of Nrf2, and to assess its clinical significance in gastric cancer.

Methods

A total of 175 gastric cancer patients who received R0 gastrectomy with standard lymph node dissection were enrolled. We immunohistochemically evaluated Nrf2 expression in the paraffin-embedded surgically resected specimens of these 175 patients. Group differences were analyzed using the χ² test, Fisher’s exact test, and the Mann–Whitney U test. Associations between Nrf2 expression and clinicopathological features, including clinical outcome, were assessed using univariate and multivariate analyses, and Kaplan-Meier curves with the log-rank test, respectively.

Results

Nrf2 immunoreactivity was predominantly identified in the nucleus of gastric cancer cells. Nrf2 positivity was closely associated with tumor size, tumor depth, lymph node metastases, lymphovascular invasion, histology and stage (p < 0.05 for all). A log-rank test indicated that the overall survival of the Nrf2-positive group was significantly poorer than that of the Nrf2-negative group (p < 0.01). And, positive Nrf2 expression was significantly associated with resistance to 5FU-based adjuvant chemotherapy (p = 0.024).

Conclusions

Nrf2 expression was positively associated with aggressive tumor behavior in gastric cancer. This result suggests that Nrf2 expression in gastric cancer is a potential indicator of worse prognosis.

Clinical significance of stanniocalcin 2 expression as a predictor of tumor progression in gastric cancer

Stanniocalcin 2 (STC2) is a glycoprotein hormone that plays an important role in calcium and phosphate homeostasis. Furthermore, recent studies have demonstrated that STC2 expression in the primary site is correlated with tumor progression in several types of malignancies. However, few reports have investigated the clinical significance of STC2 expression in the blood of patients with gastric cancer. Therefore, we examined STC2 expression as a molecular blood marker for detection of circulating tumor cells (CTCs) and assessed the relationship between STC2 expression and clinico-pathological features including prognosis in patients with gastric cancer. Quantitative PCR assay was used to assess STC2 mRNA expression in 4 gastric cancer cell lines and in blood specimens from 93 patients with gastric cancer and 22 healthy volunteers. The numbers of STC2 mRNA copies were significantly higher in the gastric cancer cell lines and in blood from patients with gastric cancer than in blood from healthy volunteers (P=0.0002 and P=0.01, respectively). STC2 expression was positive in 43 (46.2%) of the 93 patients with gastric cancer, and its expression was significantly correlated with age, depth of tumor invasion, lymph node metastasis, stage and venous invasion (P=0.023, P=0.045, P=0.035, P=0.007 and P=0.027, respectively). The 5-year survival rate was significantly lower in patients with STC2 expression compared to patients without STC2 expression (P=0.014). Our results indicate that STC2 could be a useful molecular blood marker for predicting tumor progression by monitoring CTCs in patients with gastric cancer.

Feasibility of sentinel node navigation surgery after noncurative endoscopic resection for early gastric cancer

BACKGROUND AND AIM

Recently, the use of additional surgery after noncurative endoscopic resection has gradually increased due to the rapid spread of endoscopic treatments in selected patients with early gastric cancer. Sentinel node navigation surgery (SNNS) has also been recognized as a minimally invasive surgery with personalized lymphadenectomy in early gastric cancer. Here, we assessed the feasibility of SNNS after noncurative endoscopic resection for early gastric cancer.

METHODS

Sixteen patients with early gastric cancer, in whom additional surgery had been indicated due to noncurative endoscopic resection, were enrolled. They underwent a gastrectomy with standard lymphadenectomy. One day before surgery, (99m) technetium-tin colloid was endoscopically injected into the submucosa around the tumor. After surgery, the uptake of radioisotope in dissected lymph nodes was measured using Navigator GPS. Then, all dissected lymph nodes were investigated by hematoxylin-eosin staining and immunohistochemistry using an antihuman cytokeratin monoclonal antibody.

RESULTS

Hematoxylin-eosin staining demonstrated lymph node metastasis in two (12.5%) of 16 patients and in three (0.8%) of 382 nodes. However, immunohistochemistry showed that none of the patients had lymph node micrometastasis. Sentinel nodes (SNs) were identified in all patients. The mean number of SNs was 3.1 (range, 1-6). Among two patients with lymph node metastasis, the SNs, at least, contained positive nodes. Accordingly, the false-negative and accuracy rates were 0% and 100%, respectively.

CONCLUSION

Our results indicate that SNNS may have potential as a further minimally invasive surgery in early gastric cancer patients after noncurative endoscopic resection.

Expression of stanniocalcin 1 as a potential biomarker of gastric cancer

OBJECTIVE

We investigated stanniocalcin 1 (STC 1) expression to assess its clinical utility as a blood marker in patients with gastric cancer and evaluated its biological impact in terms of tumor aggressiveness.

METHODS

Blood specimens from 93 patients with gastric cancer and 21 normal healthy volunteers were assessed by quantitative reverse transcription-polymerase chain reaction for STC 1 mRNA expression.

RESULTS

The relative numbers of STC 1 mRNA copies were significantly higher in gastric cancer cell lines and in blood specimens from patients with gastric cancer than in blood specimens from healthy volunteers (p = 0.0001 and p = 0.003, respectively). The sensitivity and specificity of STC 1 mRNA expression for discriminating patients with gastric cancer from healthy volunteers were 69.9 and 71.4%, respectively. Furthermore, the sensitivity for STC 1 mRNA was higher than that for serum carcinoembryonic antigen and carbohydrate antigen 19-9. The presence of STC 1 expression was significantly correlated with depth of tumor invasion and tumor stage (p = 0.032 and p = 0.013, respectively).

CONCLUSION

Our data strongly suggest that STC 1 is a potentially useful blood marker for predicting biological tumor aggressiveness in patients with gastric cancer.

Clinical significance of the B7-H4 coregulatory molecule as a novel prognostic marker in gastric cancer

BACKGROUND

The B7-H4 coregulatory molecule is a member of the B7 family of molecules, which regulate the T-cell-mediated immune response through CD28 receptors. Recently, B7-H4 has been reported to be a negative regulator of the immune response in patients with several malignant diseases. However, few reports have investigated the clinical significance of B7-H4 expression in patients with gastric cancer. In the present study, we analyzed B7-H4 expression and the relationship between its expression and clinicopathological factors including prognosis in gastric cancer.

METHODS

B7-H4 expression in gastric cancer cell lines and clinical gastric cancer specimens was initially assessed with the reverse transcription-polymerase chain reaction (RT-PCR). Moreover, B7-H4 and CD3 expression in 120 resected specimens from gastric cancer patients were evaluated by immunohistochemistry (IHC).

RESULTS

B7-H4 expression was identified in the gastric cancer cell lines and clinical tumor tissues by RT-PCR. B7-H4 expression was high in 25.8% (31/120) of resected tumor specimens. B7-H4 expression significantly correlated with tumor stage (P = 0.04). The 5-year survival rate was significantly lower in patients with high B7-H4 expression than in those with low B7-H4 expression (P = 0.001). Multivariate analysis demonstrated that B7-H4 expression was an independent prognostic factor (P = 0.035). Immunohistochemical analysis of CD3 expression showed that B7-H4 expression was inversely correlated with the number of tumor infiltrating T lymphocytes (P < 0.001).

CONCLUSIONS

The B7-H4 coregulatory molecule is a novel prognostic marker related to the T-cell-mediated immune response, and its pathway may be a molecular target for controlling tumor progression in patients with gastric cancer.

B7-H3 expression in gastric cancer: a novel molecular blood marker for detecting circulating tumor cells

The clinical significance of B7-H3 expression in gastric cancer remains unclear, although the B7 ligand family plays a critical role in the T cell-mediated immune response. We therefore investigated B7-H3 expression as a blood marker of circulating tumor cells and determined correlations with tumor progression in patients with gastric cancer. B7-H3 expression in gastric cell lines was initially evaluated by immunocytochemistry. Furthermore, we used quantitative RT-PCR to assess B7-H3 mRNA expression in four cell lines and in 95 blood specimens from patients with gastric cancer, as well as in 21 samples of peripheral blood lymphocytes from healthy volunteers. B7-H3 expression in cell lines was identified by immunocytochemistry and quantitative RT-PCR. Blood specimens from patients with gastric cancer contained significantly more copies of B7-H3 mRNA than those from healthy volunteers without cancer (P < 0.0001). Levels of B7-H3 expression significantly correlated with overall stage (P = 0.013). The 5-year survival rate was significantly lower in patients with high B7-H3 expression than with low expression (P = 0.02). Multivariate analysis demonstrated that B7-H3 expression was an independent prognostic factor (P = 0.046). Our results indicate that B7-H3 appears to be a useful blood marker for predicting tumor progression in gastric cancer.

B7-H3 expression in gastric cancer: a novel molecular blood marker for detecting circulating tumor cells

The clinical significance of B7-H3 expression in gastric cancer remains unclear, although the B7 ligand family plays a critical role in the T cell-mediated immune response. We therefore investigated B7-H3 expression as a blood marker of circulating tumor cells and determined correlations with tumor progression in patients with gastric cancer. B7-H3 expression in gastric cell lines was initially evaluated by immunocytochemistry. Furthermore, we used quantitative RT-PCR to assess B7-H3 mRNA expression in four cell lines and in 95 blood specimens from patients with gastric cancer, as well as in 21 samples of peripheral blood lymphocytes from healthy volunteers. B7-H3 expression in cell lines was identified by immunocytochemistry and quantitative RT-PCR. Blood specimens from patients with gastric cancer contained significantly more copies of B7-H3 mRNA than those from healthy volunteers without cancer (P < 0.0001). Levels of B7-H3 expression significantly correlated with overall stage (P = 0.013). The 5-year survival rate was significantly lower in patients with high B7-H3 expression than with low expression (P = 0.02). Multivariate analysis demonstrated that B7-H3 expression was an independent prognostic factor (P = 0.046). Our results indicate that B7-H3 appears to be a useful blood marker for predicting tumor progression in gastric cancer.

Expression of B7-H4 in blood of patients with gastric cancer predicts tumor progression and prognosis

BACKGROUND AND OBJECTIVES

B7-H4 is a novel molecular B7 ligand that plays an important role as a negative regulator of the T cell-mediated immune response. However, the clinical significance of B7-H4 expression in gastric cancer remains uncertain. Here, we assessed B7-H4 expression in blood of patients with gastric cancer to determine whether or not it can predict tumor progression and prognosis.

METHODS

We measured B7-H4 mRNA expression by quantitative RT-PCR in five gastric cell lines as well as in blood specimens from 94 patients with gastric cancer and from 22 healthy volunteers.

RESULTS

Significantly more B7-H4 mRNA copies were found in gastric cell lines and in blood from patients with gastric cancer than in blood from healthy volunteers (P < 0.0001 and P < 0.0001, respectively). B7-H4 expressed in 71 (75.5%) of 94 patients with gastric cancer significantly correlated with depth of tumor invasion, lymph node metastasis, and overall stage (P = 0.006, P = 0.001, and P < 0.001, respectively). The 5-year survival rate was significantly lower in patients with than without B7-H4 expression (P = 0.04).

CONCLUSIONS

The evaluation of B7-H4 expression in blood is a useful tool for predicting the progression of gastric cancer and prognosis.

CCR7 and CXCR4 expression predicts lymph node status including micrometastasis in gastric cancer

The chemokine receptors CCR7 and CXCR4 play a major role in the mechanism of lymph node metastasis from primary tumor cells. We postulated that their expression in gastric tumor cells could predict lymph node status including lymph node micrometastasis (LNMM). We assessed CCR7 and CXCR4 expression in 93 resected gastric tumor specimens by immunohistochemistry. Dissected lymph nodes were examined by reverse transcription-polymerase chain reaction and immunohistochemistry using cytokeratin monoclonal antibody to detect LNMM in addition to hematoxylin-eosin (H&E) staining. Levels of CCR7 and CXCR4 expression were high in 26.9% (25/93) and in 32.3% (30/93), respectively of tumor cells and the levels significantly correlated with lymph node metastasis according to H&E staining (P=0.0212 and P=0.0115, respectively). We identified LNMM in 25 of 83 (30.1%) node-negative patients. Both CCR7 and CXCR4 expression significantly correlated with lymph node status including LNMM (P=0.0092 and P=0.0075, respectively). Furthermore, levels of combined CCR7 and CXCR4 expression significantly correlated with lymph node metastatic status (P=0.0021). Assessment of CCR7 and CXCR4 expression in gastric cancer is a useful tool for predicting lymph node metastatic status including LNMM.

Vascular endothelial growth factor-C and -D expression correlates with lymph node micrometastasis in pN0 early gastric cancer

BACKGROUND AND OBJECTIVES

Vascular endothelial growth factors (VEGF)-C and -D play an important role in lymphangiogenesis, and the expressions of these factors are related to lymphatic invasion and lymph node metastasis in various malignant neoplasms. The present study investigates the expression of VEGF-C and -D in early gastric cancer and analyzes its relationship to lymph node micrometastasis determined by reverse transcription-polymerase chain reaction (RT-PCR).

METHODS

We examined 1,828 lymph nodes obtained from 80 patients with node-negative early gastric cancer. All dissected lymph nodes were examined by RT-PCR for CEA mRNA in addition to hematoxylin-eosin staining. The resected primary specimens were immunostained using anti-VEGF-C and -D polyclonal antibodies.

RESULTS

The incidence of lymph node micrometastasis determined by RT-PCR was 23.8% (19/80). The high expression of VEGF-C and -D was found in 27.5% (22/80) and in 21.3% (17/80), respectively. The expression of VEGF-C and -D was closely related to lymph node micrometastasis (P = 0.0390 and 0.0213, respectively).

CONCLUSIONS

We demonstrated a close relationship between micrometastasis and VEGF-C and -D expression of the primary tumor. Thus, levels of VEGF-C and -D expression might be useful for predicting micrometastasis in patients with early gastric cancer.

Evaluation of sentinel node concept in gastric cancer based on lymph node micrometastasis determined by reverse transcription-polymerase chain reaction

OBJECTIVE

To determine the adequacy of sentinel node (SN) concept based on micrometastasis using immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR) in gastric cancer.

SUMMARY BACKGROUND DATA

The SN concept has recently been introduced in gastrointestinal tract cancers. The precise detection of lymph node metastasis including micrometastasis is important for SN navigation surgery.

METHODS

Sixty-one patients with gastric cancer who were preoperatively diagnosed with T1-T2 (cT1-T2) and N0 (cN0) were enrolled. They underwent standard radical gastrectomy with lymph node dissection. One day before surgery, 4 mCi of (99m)Technetium-tin colloid was endoscopically injected into the submucosa around the tumor. During surgery, radioisotope uptake in the lymph node was measured using Navigator GPS. All dissected lymph nodes were examined by RT-PCR in addition to hematoxylin and eosin staining and IHC.

RESULTS

Sentinel nodes were identified in all patients (100%). The incidences of metastasis determined by hematoxylin and eosin and IHC were 8.2% (5 of 61) and 13.1% (8 of 61), respectively. Micrometastases undetectable by IHC were identified in 14 patients (23.0%) by RT-PCR. Only 1 patient had micrometastasis detectable by RT-PCR in lymph nodes other than SN, but this patient had a cT2 tumor. In patients with cT1 and cN0 tumors, the false negative and accuracy rates were 0% and 100%, respectively.

CONCLUSIONS

Although the incidence of micrometastasis detected by RT-PCR was quite high, SN navigation identified such metastasis in all patients except one. Thus, the SN concept was applicable to patients with cT1 and cN0 gastric cancer, even when micrometastasis was detectable by RT-PCR.

Lymphatic invasion using D2-40 monoclonal antibody and its relationship to lymph node micrometastasis in pN0 gastric cancer

The monoclonal antibody D2-40 is a specific lymphatic endothelial markers and D2-40 staining have been applicable to evaluate lymphatic invasion in various malignant neoplasms. In the present study, we investigated lymph node micrometastasis determined by immunohistochemistry (IHC) and reverse transcription–polymerase chain reaction (RT–PCR) in all dissected lymph nodes obtained from 80 patients with node-negative gastric cancer, and analysed the relationship between micrometastasis and clinicopathological findings including lymphatic invasion of the resected primary tumour using D2-40 immunohistochemical staining. The incidence of micrometastasis determined by IHC and RT–PCR was 11.3% (nine out of 80) and 31.3% (25 out of 80), respectively. Although haematoxylin–eosin (HE) staining revealed lymphatic invasion in 11.3% (nine out of 80) of patients, D2-40 staining uncovered new invasion in 23.8% (19 out of 80) of patients. In the diagnosis of HE and D2-40 staining, the incidence of micrometastasis was significantly higher in patients with lymphatic invasion than in those without lymphatic invasion (P=0.0150 and P<0.0001, respectively). Micrometastasis correlated more closely with D2-40 than with HE staining. We demonstrated a high incidence of micrometastasis and lymphatic invasion and a correlation between them even in pN0 gastric cancer. When planning less invasive treatment, the presence of such occult cancer cells should be considered.