Abstract P6-09-25: Circulating tumor cell clusters-associated gene plakoglobin is a novel prognostic predictor in patients with breast cancer

Background: Accumulating evidence shows that circulating tumor cells (CTC) are linked to metastatic relapse and are regarded as a prognostic marker for human cancer. It was reported that CTC clusters (CTCc) have more metastatic potential than single CTC. Lately, studies also show that the high expression of plakoglobin, a cell adhesion protein, within the primary tumor are positively associated with CTCc in breast cancer patients. In addition, it is thought that insufficient expression of plakoglobin could promote epithelial-mesenchymal transition (EMT). In this study, we investigated the correlation between plakoglobin expression and survival of breast cancer.

Materials and Methods:A total of 126 patients with resectable early-stage breast cancer were treated with neoadjuvant chemotherapy (NAC). All patients received a standardized protocol of NAC consisting of four courses of FEC100 (500 mg/m2 fluorouracil, 100 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide) every 3 weeks, followed by 12 courses of 80 mg/m2 paclitaxel administered weekly. The expression of plakoglobin were identified by immunohistochemical staining properties in cell membrane. Staining with plakoglobin (clone 4C12) was scored according to the percentage of cells that stained positively: low, 0-25%; medium, 26-75%; high, >75%. We investigated the correlation between the plakoglobin expression in primary tumor specimen and clinical outcomes including overall-survival (OS), disease-free-survival (DFS), distant-metastasis-free-survival (DMFS), the efficacy of NAC. And we examined the relation between the expression of plakoglobin and E-cadherin, EMT marker.

Results: The patient with high plakoglobin expression had significantly worse OS (p=0.021, log-rank) and DFS (p=0.015, log-rank), DMFS (p=0.040, log-rank). And the plakoglobin expression had no correlation with pathological complete response (pCR) rate (p=0.596). Also, there was not a statistically significant relationship between the plakoglobin expression and other clinicopathological parameters including tumor size (p=0.708), lymph node status (p=0.479), subtype (p=0.413), nuclear grade (p=0.642), Ki67 (p=0.202), tumor infiltrating lymphocytes (p=0.828). On univariate analysis with respect to distal metastasis, high plakoglobin expression showed worse prognosis than low plakoglobin expression (p=0.013, hazard ratio=4.221). And multivariate analysis found the same result (p=0.015, hazard ratio=4.070). In addition, there was a significant relationship between the expression of plakoglobin and E-cadherin (p=0.023).

Conclusions: Plakoglobin expression is an independent prognostic factor in the patients with breast cancer; particularly for DMFS, and this mechanism related to EMT.Background: Accumulating evidence shows that circulating tumor cells (CTC) are linked to metastatic relapse and are regarded as a prognostic marker for human cancer. It was reported that CTC clusters (CTCc) have more metastatic potential than single CTC. Lately, studies also show that the high expression of plakoglobin, a cell adhesion protein, within the primary tumor are positively associated with CTCc in breast cancer patients. In addition, it is thought that insufficient expression of plakoglobin could promote epithelial-mesenchymal transition (EMT). In this study, we investigated the correlation between plakoglobin expression and survival of breast cancer.

Materials and Methods:A total of 126 patients with resectable early-stage breast cancer were treated with neoadjuvant chemotherapy (NAC). All patients received a standardized protocol of NAC consisting of four courses of FEC100 (500 mg/m2 fluorouracil, 100 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide) every 3 weeks, followed by 12 courses of 80 mg/m2 paclitaxel administered weekly. The expression of plakoglobin were identified by immunohistochemical staining properties in cell membrane. Staining with plakoglobin (clone 4C12) was scored according to the percentage of cells that stained positively: low, 0-25%; medium, 26-75%; high, >75%. We investigated the correlation between the plakoglobin expression in primary tumor specimen and clinical outcomes including overall-survival (OS), disease-free-survival (DFS), distant-metastasis-free-survival (DMFS), the efficacy of NAC. And we examined the relation between the expression of plakoglobin and E-cadherin, EMT marker.

Results: The patient with high plakoglobin expression had significantly worse OS (p=0.021, log-rank) and DFS (p=0.015, log-rank), DMFS (p=0.040, log-rank). And the plakoglobin expression had no correlation with pathological complete response (pCR) rate (p=0.596). Also, there was not a statistically significant relationship between the plakoglobin expression and other clinicopathological parameters including tumor size (p=0.708), lymph node status (p=0.479), subtype (p=0.413), nuclear grade (p=0.642), Ki67 (p=0.202), tumor infiltrating lymphocytes (p=0.828). On univariate analysis with respect to distal metastasis, high plakoglobin expression showed worse prognosis than low plakoglobin expression (p=0.013, hazard ratio=4.221). And multivariate analysis found the same result (p=0.015, hazard ratio=4.070). In addition, there was a significant relationship between the expression of plakoglobin and E-cadherin (p=0.023).

Conclusions: Plakoglobin expression is an independent prognostic factor in the patients with breast cancer; particularly for DMFS, and this mechanism related to EMT.

Citation Format: Goto W, Kashiwagi S, Asano Y, Takada K, Takashima T, Morisaki T, Noda S, Onoda N, Ohsawa M, Hirakawa K, Ohira M. Circulating tumor cell clusters-associated gene plakoglobin is a novel prognostic predictor in patients with breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-25.

Abstract P3-04-20: Predicting therapeutic effect by on tumor invasion lymphocytes (TILs) in endocrine therapy for stage IV breast cancer

Background: Breast cancer with distant metastasis at first presentation (stage IV disease) is often encountered in the outpatient department. With recent advances in multimodal therapies for breast cancer, long-term survival can now be expected even in stage IV breast cancer with distant metastasis. However, a goal in treating metastatic disease is prolongation of survival while maintaining good quality of life (QOL). Endocrine therapy is suitable for this purpose.The tumor immune environment not only modulates the effects of immunotherapy, but also the effects of other anticancer drugs and treatment outcomes. These immune responses can be evaluated with tumor-infiltrating lymphocytes (TILs), which has frequently been verified clinically. In the present study, we hypothesized that TILs would be useful as predictive marker of the therapeutic effect in endocrine therapy as well. In this study, the prediction of the therapeutic effect by TILs in endocrine therapy for stage IV breast cancer was clinically verified.

Materials and Methods:Data from 40 patients who underwent endocrine therapy as the initial drug therapy for stage IV breast cancer were used. The correlation between TILs evaluated according to the standard method, and prognosis, including the efficacy of endocrine therapy, was investigated retrospectively. Patients with 350% lymphocytic infiltration were considered to have lymphocyte-predominant breast cancer (LPBC).

Results:Among all 40 patients, TIL levels were high in 13 (32.5%) and low in 27 (67.5%) patients. Nine patients (22.5%) had LPBC, and 31 patients (77.5%) had non-LPBC. Investigation of the clinical pathological features of patients showed no significant differences between the high TIL and low TIL groups. There were also no significant differences between LPBC and non-LPBC patients. An analysis of outcomes comparing the high TIL and low TIL groups showed no prolongation in progression-free survival (PFS) (p=0.171, log-rank), time to treatment failure (TTF)(p=0.054), or overall survival (OS) (p=0.641). LPBC patients had significant prolongations of PFS (p=0.005), TTF (p=0.001), and OS (p=0.027) compared to non-LPBC patients. On receiver operating characteristic (ROC) curve analyses, results were better with LPBC (AUC: 0.700) than with TILs (AUC: 0.606).

Conclusion: The present findings suggest that a high level of lymphocytic infiltration in the tumor stroma may serve as a predictor of the therapeutic effect of endocrine therapy for patients with stage IV ER-positive breast cancer.

Citation Format: Kashiwagi S, Asano Y, Goto W, Takada K, Takashima T, Morisaki T, Noda S, Onoda N, Ohsawa M, Hirakawa K, Ohira M. Predicting therapeutic effect by on tumor invasion lymphocytes (TILs) in endocrine therapy for stage IV breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P3-04-20.

Abstract P2-05-05: Prediction of survival after neoadjuvant chemotherapy for breast cancer by evaluation of tumor-infiltrating lymphocytes (TILs) and residual cancer burden (RCB)

Background: The tumor immune environment not only modulates the effects of immunotherapy, but also the effects of other anticancer drugs and treatment outcomes. Thus, the importance of inhibiting and improving the tumor immune microenvironment is now recognized. These immune responses can be evaluated with tumor-infiltrating lymphocytes (TILs), which has frequently been verified clinically. On the other hand, residual cancer burden (RCB) evaluation has been shown to be a useful predictor of survival after neoadjuvant chemotherapy (NAC). In this study, RCB and TILs evaluations were combined to produce an indicator that we have termed “RCB-TILs”, and its clinical application to NAC for breast cancer was verified by subtype-stratified analysis.

Materials and Methods:A total of 177 patients with resectable early-stage breast cancer were treated with NAC.The correlation between TILs evaluated according to the standard method, and prognosis, including the efficacy of NAC, was investigated retrospectively. The RCB was calculated using the Residual Cancer Burden Calculator on the website of the MD Anderson Cancer Center. The RCB and TILs evaluations were combined to create the “RCB-TILs”. Patients who were RCB-positive and had high TILs were considered RCB-TILs-positive, and all other combinations were RCB-TILs-negative.

Results: Univariable analysis of patients with high TILs found that this contributed significantly to prolonging DFS in all patients (p = 0.022, hazard ratio = 0.420), TNBC patients (p = 0.004, hazard ratio = 0.177), and HER2BC patients (p = 0.026, hazard ratio = 0.123). For HRBC patients, however, high TILs did not contribute to survival (p = 0.990, hazard ratio = 0.992). Being RCB-TILs-positive, however, contributed significantly to prolonging DFS in all patients (p < 0.001, hazard ratio = 0.181), TNBC patients (p < 0.001, hazard ratio = 0.099), HER2BC patients (p = 0.026, hazard ratio = 0.123), and HRBC patients (p = 0.039, hazard ratio = 0.258). On multivariable analysis, being RCB-TILs-positive was an independent factor for recurrence after NAC in all patients (p < 0.001, hazard ratio = 0.048), TNBC patients (p = 0.018, hazard ratio = 0.041), HER2BC patients (p = 0.036, hazard ratio = 0.134), and HRBC patients (p = 0.002, hazard ratio = 0.081).

Conclusion: The results of the present study suggest that RCB-TILs is a significant predictor for breast cancer recurrence after NAC and may be a more sensitive indicator than TILs alone.

Citation Format: Asano Y, Kashiwagi S, Goto W, Takada K, Takashima T, Morisaki T, Noda S, Onoda N, Ohsawa M, Hirakawa K, Ohira M. Prediction of survival after neoadjuvant chemotherapy for breast cancer by evaluation of tumor-infiltrating lymphocytes (TILs) and residual cancer burden (RCB) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-05-05.

Tumour-infiltrating CD8 to FOXP3 lymphocyte ratio in predicting treatment responses to neoadjuvant chemotherapy of aggressive breast cancer

BACKGROUND

Tumour-infiltrating lymphocytes (TILs) can be used to monitor the immune response, and are important in predicting treatment responses and outcomes for various types of cancer. Recently, specific TIL subsets have been reported to be clinically useful in predicting treatment responses. The CD8+/FOXP3+ TIL ratio (CFR) may be a more sensitive indicator for monitoring immune function. This study investigated the clinical significance and value of CFR as a biomarker to predict treatment responses to neoadjuvant chemotherapy for breast cancer.

METHODS

Patients with resectable early-stage breast cancer treated with neoadjuvant chemotherapy at Osaka City University Hospital, Japan, between 2007 and 2013 were included. Oestrogen receptor, progesterone receptor, human epidermal growth factor receptor (HER) 2, Ki-67, CD8 and FOXP3 status were assessed by immunohistochemistry, and correlated with pathological complete response (pCR).

RESULTS

A total of 177 patients were included, of whom 90 had a high CFR and 87 a low CFR. Triple-negative breast cancer (TNBC) was more common in the high-CFR group than in the low-CFR group (46 versus 23 per cent; P = 0·002), as was HER2-enriched breast cancer (HER2BC) (27 versus 14 per cent; P = 0·033). Among these patients, the pCR rate was significantly higher in the high-CFR group than in the low-CFR group (TNBC: P = 0·022; HER2BC: P < 0·001). In multivariable analysis high-CFR status was an independent predictor of a favourable prognosis: hazard ratio 0·24 (95 per cent c.i. 0·05 to 0·72; P = 0·015) for TNBC and 0·10 (0·10 to 0·90; P = 0·041) for HER2BC.

CONCLUSION

The CFR may be a useful biomarker to predict treatment response to neoadjuvant therapy in aggressive breast cancer subtypes, such as TNBC and HER2BC.

Abstract P3-07-33: Prediction of the treatment response to neoadjuvant chemotherapy in breast cancer by subtypes using tumor-infiltrating lymphocytes

Purpose: Monitoring the host immunological response to cancer in the microenvironment of the interaction between tumor and the body plays an important role in predicting treatment response and outcomes. Recent interest has focused on the morphological evaluation of tumor-infiltrating lymphocytes (TILs) in breast cancer (BC) and on the evidence showing their clinical relevance. Meanwhile, no consensus has yet been reached on standard methods for pathological evaluation of TILs. Therefore, methods of evaluation have differed in reports to date showing the clinical relevance of TILs. An International Working Group (2014) announced recommendations for evaluating TILs in an effort to improve consistency and reproducibility. In this study, the clinical validity and utility of TILs in NAC were investigated based on this recommendation with a stratified analysis by BC subtypes. Changes in TILs after recurrence, which have seldom been reported to date, are also discussed.

Experimental Design: TILs was evaluated in 177 patients with breast cancer treated with NAC and subsequent curative surgery. All patients received a standardized protocol of NAC consisting of four courses of FEC100 (500 mg/m2 fluorouracil, 100 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide) every 3 weeks, followed by 12 courses of 80 mg/m2 paclitaxel administered weekly. Forty-five patients had HER2-positive breast cancer and were additionally administered weekly (2 mg/kg) or tri-weekly (6 mg/kg) trastuzumab during paclitaxel treatment. The correlation between TILs evaluated according to the standard method, and prognosis, including the efficacy of NAC, was investigated retrospectively.

Results: In the 96 high-TIL group, compared to the 81 low-TIL group, triple-negative breast cancer (TNBC) (p &lt; 0.001) and HER2-enriched (p = 0.040) were significantly more frequent, and the pathological complete response (pCR) rate were significantly higher (p = 0.003). On multivariate analysis also demonstrated that high-TIL status was an independent factor to indicate significantly more favorable prognosis of the patients compared with low-TIL status (p = 0.036, HR = 0.45). Among the 61 TNBC and the 36 HER2-enriched patients, the pCR rate was significantly higher in the high-TIL group than in the low-TIL group (p = 0.013) (p = 0.014). On multivariate analysis also showed that high-TIL status was an independent factor to predict the favorable prognosis (p = 0.023, HR = 0.24) (p = 0.036, HR = 0.13). Biopsy specimens from local recurrence after successful NAC frequently showed decreased TILs.

Conclusion: TILs may be a biomarker to predict treatment response to NAC in patients with TNBC and HER2-enriched subtypes of BC. A decrease in TILs may also be associated with tumor recurrence.

Citation Format: Kashiwagi S, Asano Y, Goto W, Morisaki T, Noda S, Takashima T, Onoda N, Hirakawa K. Prediction of the treatment response to neoadjuvant chemotherapy in breast cancer by subtypes using tumor-infiltrating lymphocytes. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-33.

Abstract P4-04-14: Prediction of treatment responses to neoadjuvant chemotherapy in triple-negative breast cancer by analysis of immune checkpoint protein expression

Purpose: "Avoiding immune destruction" has recently been established as one of the hallmarks of cancer. The programmed cell death (PD)-1/programmed cell death-ligand (PD-L) 1 pathway is also an important immunosuppression mechanism that allows cancer cells to escape host immunity. The effect of the tumor immune environment not only on immunotherapy effectiveness, but also on conventional anti-tumor therapy effectiveness and prognosis, has recently been demonstrated. Thus, improvement of the tumor immune environment is important. In other words, the tumor immune environment plays a role in the anti-tumor effects of conventional anti-tumor drugs. Moreover, immune checkpoint proteins such as PD-1, PD-L1, and PD-L2 may play an important role in improving the tumor immune environment. Given this background, the clinical significance of immune checkpoint protein expression was investigated in patients receiving neoadjuvant chemotherapy (NAC) for breast cancer using conventional anti-cancer drugs, and whether this would be useful as a marker to predict treatment response was evaluated.

Experimental Design: A total of 177 patients with resectable early-stage breast cancer were treated with NAC. All patients received a standardized protocol of NAC consisting of four courses of FEC100 (500 mg/m2 fluorouracil, 100 mg/m2 epirubicin, and 500 mg/m2 cyclophosphamide) every 3 weeks, followed by 12 courses of 80 mg/m2 paclitaxel administered weekly. Forty-five patients had HER2-positive breast cancer and were additionally administered weekly (2 mg/kg) or tri-weekly (6 mg/kg) trastuzumab during paclitaxel treatment. ER, PR, HER2, Ki67, PD-L1, PDL-2 and PD-1 status were assessed by immunohistochemistry on core needle biopsy specimens.

Results: There were 37 (20.9%) patients with high PD-1 expression, 42 (23.7%) patients had high PD-L1 expression, and 52 (29.4%) patients had high PD-L2 expression. The patients with high PD-1 and PD-L1 expressions had a significantly higher rate of triple-negative breast cancer (TNBC) (p=0.041) (p&lt;0.001). Univariate analysis showed that PD-1 and PD-L1 expressions were associated with significantly shorter DFS (p=0.008, HR=2.752) (p=0.002, HR=3.194). However, although multivariate analysis showed that lymph node metastases were an independent poor prognostic factor (p=0.046, HR=4.330), PD-1 and PD-L1 expressions were not independent prognostic factors (p=0.492, HR=1.415) (p=0.084, HR=2.613). In TNBC, patients with high PD-1 and PD-L1 expressions had significantly higher rates of non-pCR (p=0.003) (p&lt;0.001). Univariate analysis showed that PD-1 and PD-L1 expressions also significantly shortened disease free survival in TNBC (p=0.048, HR=3.318) (p=0.007, HR=8.375). However, multivariate analysis found that only PD-L1 expression was an independent prognostic factor (p=0.041, HR=9.479).

Conclusions: PD-1 and PD-L1 expressions may be useful as biomarkers to predict treatment responses to NAC in breast cancer. Above all, PD-L1 expression may also be useful as biomarkers for more effective chemotherapy in TNBC.

Citation Format: Asano Y, Kashiwagi S, Goto W, Morisaki T, Noda S, Takashima T, Onoda N, Hirakawa K. Prediction of treatment responses to neoadjuvant chemotherapy in triple-negative breast cancer by analysis of immune checkpoint protein expression. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-04-14.

T-cell receptor ζ mRNA with an alternatively spliced 3' untranslated region is generated predominantly in the peripheral blood T cells of systemic lupus erythematosus patients

Abstract  To investigate the mechanism of the downregulation of T-cell receptor ζ chain (TCRζ) expression in the peripheral blood T cells (PBTs) of systemic lupus erythematosus (SLE) patients, we analyzed the 3' untranslated region (3'UTR) of TCRζ mRNA, because the 3'UTR in mRNA is responsible for posttranscriptional regulation. Use of the reverse transcriptase polymerase chain reaction (RT-PCR) to amplify the 917 bp TCRζ 3'UTR cDNA demonstrated that the short variant cDNA (355 bp), expressed as an alternatively spliced 3'UTR with 562-bp deletion, was predominated in the PBTs of 11 of 14 SLE patients, whereas mainly the wild-form cDNA (917 bp) was detected in the PBTs of seven negative controls (two systemic sclerosis patients, five normal controls) and in two T-cell line hybridomas. Semiquantitative PCR also revealed the predominant expression of the TCRζ mRNA with alternatively spliced 3'UTR (TCRζ mRNA/as-3'UTR), and a decreased expression of TCRζ mRNA with the wild form 3'UTR (TCRζ mRNA/w-3'UTR) in SLE T cells. However, there was no difference in the expression of the open reading frame (ORF) TCRζ mRNA between the negative controls and SLE patients. The TCRζ protein expression level according to Western blot analysis correlated well with that of TCRζ mRNA/w-3'UTR (r= 0.931) and reversibly with TCRζ mRNA/as-3'UTR (r=-0.614), but not with ORF TCRζ mRNA (r=-0.296). It can be concluded that the reduced expression of TCRζ mRNA/w-3'UTR and the predominant expression of TCRζ mRNA/as-3'UTR lead to downregulation of the TCRζ protein in SLE T cells.

c-Kit expression as a prognostic molecular marker in patients with basal-like breast cancer

Background

As patients with basal-like breast cancer (BLBC) have a poor prognosis and there is no specifically tailored therapy, molecular biological characterization of BLBC is necessary. c-Kit is a transmembrane receptor tyrosine kinase known to play important roles in various solid cancers. This study classified BLBCs from patients with breast carcinoma, and addressed the significance of c-Kit expression in these tumours.

Methods

Primary breast tumours were stained with antibodies against oestrogen receptor, progesterone receptor, human epidermal growth factor receptor (HER) 2, epidermal growth factor receptor (EGFR), cytokeratin 5/6 and c-Kit. The association between c-Kit, BLBC and survival was analysed.

Results

A total of 667 patients with breast cancer were followed up for a median of 39 (range 6–72) months. Some 190 tumours (28·5 per cent) were classified as triple-negative for breast cancer (negative for oestrogen receptor, progesterone receptor and HER2) and 149 (78·4 per cent) had characteristics of BLBC (positive for cytokeratin 5/6 and/or EGFR). c-Kit expression was detected in 111 (16·6 per cent) of 667 tumours. c-Kit-positive tumours were more commonly found among patients with BLBC (42 of 149, 28·2 per cent; P &lt; 0·001) and in patients with nodal metastasis (47 of 216, 21·8 per cent; P = 0·014) than in those without. In patients with BLBC, the prognosis was significantly worse in those with c-Kit expression (P &lt; 0·001). Multivariable logistic regression analysis revealed c-Kit as an independent negative prognostic factor for cancer-specific survival in patients with BLBC (hazard ratio 2·29, 95 per cent confidence interval 1·11 to 4·72).

Conclusion

c-Kit might be a prognostic marker and possible molecular target for therapy in patients with BLBC.

Establishment and characterization of a new human gallbladder carcinoma cell line (OCUG-1) producing TA-4

A new human cell line (OCUG-1) was established from peritoneal effusion of a patient with malignant gallbladder carcinoma. OCUG-1 cells proliferated mainly in clusters of cells partially floating in a monolayered sheet. The population doubling time is 47.1 h. DNA analysis showed that OCUG-1 cells were aneuploid and had two G(0)/G(1) peaks. The number of chromosomes was distributed in a broad range from 52 to 139. Subcutaneous injections of the cells induced tumor formation in all nude mice. The reconstituted tumors were poorly differentiated adenocarcinoma. High levels of SLX, CA19-9, SPan-1 and TA-4 were found in the serum of the original patient, but OCUG-1 cells produced only TA-4. We speculate that OCUG-1 may be a transitional form from adenocarcinoma to squamous cell carcinoma. Since OCUG-1 produces a high level of TA-4, it will be useful for the study of the biological nature of this carcinoma and the relationship between the expression of TA-4 and squamatization.

Combined evaluation of urokinase-type plasminogen activator and plasminogen activator inhibitor-2 expression in gastric carcinoma

Urokinase-type plasminogen activator (UPA) is a serine protease implicated in cancer invasion and metastasis. There are at least two kinds of specific inhibitor which act on UPA: plasminogen activator inhibitor-1 (PAI-1) and plasminogen activator inhibitor-2 (PAI-2). It has been reported that both UPA and PAI-1 antigen levels are associated with short survival in patients with breast cancer. In this study, we investigated the correlation between the expression of UPA, PAI-2 and prognosis in gastric carcinoma. One hundred and twenty specimens resected from patients with gastric carcinoma were investigated by staining with monoclonal antibodies against UPA and PAI-2. UPA positive rate was significantly higher in patients with liver metastases than in those without such metastases, There was no significant association between PAI-2 expression and clinicopathologic factors. However, patients with UPA-positive and PAI-2-negative tumors had more advanced cancer than other patients. According to the prognosis, the patients with UPA-positive and PAI-2-negative tumors had a significantly poorer prognosis than other patients. In conclusion, the combined evaluation of UPA and PAI-2 expression is associated with tumor progression in gastric cancer.

Effects of N-methyl-D-aspartate glutamate receptor antagonists on oscillatory signal propagation in the guinea-pig accessory olfactory bulb slice: characterization by optical, field potential and patch clamp recordings

To characterize the role of N-methyl-d-aspartate glutamate receptors in oscillations induced by a single electrical stimulation of the vomeronasal nerve layer, optical, field potential and patch clamp recordings were carried out in guinea-pig accessory olfactory bulb slice preparations. Bath application of the N-methyl-D-aspartate receptor antagonists, 2-amino-5-phosphonovaleric acid or MK-801, produced an increase in frequency of oscillating waves (oscillation) in external plexiform and mitral cell layers. The removal of Mg2+ from perfusate abolished oscillations, while subsequent application of 2-amino-5-phosphonovaleric acid or MK-801 restored oscillations. Vomeronasal nerve layer-evoked postsynaptic currents were analyzed by whole-cell clamp recordings from mitral and granule cells. A long-lasting excitatory postsynaptic current and periodic inhibitory postsynaptic currents, which were superimposed on the long excitatory postsynaptic current, were observed in mitral cells. The frequency of the periodic inhibitory postsynaptic currents correlated with the frequency of oscillations observed in the optical and field potential recordings. Furthermore, periodic inhibitory postsynaptic currents were blocked by puff application of bicuculline to the external plexiform layer/mitral cell layer, where mitral cells make dendrodendritic synapses with granule cells. In addition, puff application of the non-N-methyl-D-aspartate antagonist, 6-cyano-7-nitroquinoxaline-2,3-dione, to the external plexiform layer/mitral cell layer suppressed an early phase of periodic inhibitory postsynaptic currents (membrane oscillation), whereas 2-amino-5-phosphonovaleric acid suppressed the late phase of periodic inhibitory postsynaptic currents. These data indicate that periodic excitatory postsynaptic currents of granule cells induce relevantly periodic inhibitory postsynaptic currents in mitral cells via dendrodendritic synapses and suggest that feedback inhibition regulates generation of oscillation via activation of non-N-methyl-d-aspartate glutamate receptors and gradual attenuation of oscillation via activation of N-methyl-D-aspartate receptors on granule cells.

TGF-beta1 down-regulates ICAM-1 expression and enhances liver metastasis of pancreatic cancer

PURPOSE

In order to study the regulation of adhesion-molecule expression by cytokines, we have investigated the effect of transforming growth factor-beta1. (TGF-beta1) on the expression of intercellular adhesion molecule-1 (ICAM-1) in human pancreatic cancer cell lines.

MATERIAL AND METHODS

By using three pancreatic cancer cell lines, SW1990, CAPAN-2 and PANC-1, the effect of TGF-beta1 on expression of ICAM-1, cancer cell immunogenicity and liver metastasis were investigated.

RESULTS

Cell surface ICAM-1 expression by ELISA on three cell lines were all reduced significantly by following incubation with various concentrations of TGF-beta1 and down-regulation of ICAM-1 expression was also observed at the mRNA level. Corresponding to the down expression of ICAM-1, the adhesion of peripheral blood mononuclear lymphocytes (PBMLs) to cancer cells and cancer cell cytotoxicity during co-culture with PBMLs were remarkably decreased by treatment with TGF-beta1. Furthermore, enhanced liver metastatic potential by in vivo splenic injection was observed in CAPAN-2 cells pretreated with TGF-beta1.

CONCLUSIONS

Since decreased expression of ICAM-1 has been known to contribute to cancer cell escape from immunologic recognition and cytotoxicity by effector cells, the present results indicate that unknown function of TGF-beta1 in the tumor progression and metastasis of pancreatic cancer.