Stromal SLIT2 impacts on pancreatic cancer-associated neural remodeling.

Pancreatic ductal adenocarcinoma (PDA) is a critical health issue in the field of cancer, with few therapeutic options. Evidence supports an implication of the intratumoral microenvironment (stroma) on PDA progression. However, its contribution to the role of neuroplastic changes within the pathophysiology and clinical course of PDA, through tumor recurrence and neuropathic pain, remains unknown, neglecting a putative, therapeutic window. Here, we report that the intratumoral microenvironment is a mediator of PDA-associated neural remodeling (PANR), and we highlight factors such as 'SLIT2' (an axon guidance molecule), which is expressed by cancer-associated fibroblasts (CAFs), that impact on neuroplastic changes in human PDA. We showed that 'CAF-secreted SLIT2' increases neurite outgrowth from dorsal root ganglia neurons as well as from Schwann cell migration/proliferation by modulating N-cadherin/ß-catenin signaling. Importantly, SLIT2/ROBO signaling inhibition disrupts this stromal/neural connection. Finally, we revealed that SLIT2 expression and CAFs are correlated with neural remodeling within human and mouse PDA. All together, our data demonstrate the implication of CAFs, through the secretion of axon guidance molecule, in PANR. Furthermore, it provides rationale to investigate the disruption of the stromal/neural compartment connection with SLIT2/ROBO inhibitors for the treatment of pancreatic cancer recurrence and pain.

Quantitative immunohistochemical expression of c Kit in breast carcinomas is predictive of patients' outcome.

BACKGROUND: c Kit (CD117) expression in tissues has been reported as a relevant target for specific therapy in some human malignancies, but has been poorly documented in breast carcinomas. METHODS: The prognostic significance of c Kit in a series of 924 breast carcinomas (mean follow-up, 79 months) was investigated using standardised high-throughput quantitative densitometry of immunohistochemical precipitates in tissue microarrays. RESULTS: c Kit was expressed in 14.7% breast carcinomas (and in 42 out of 586 node-negative tumours). In univariate analysis, (log-rank test) the score of c Kit expression correlated with poor patient outcome P=0.02 and particularly in node-negative cases (P=0.002). In multivariate Cox analysis, c Kit was an indicator of metastasis independent of 25 other concomitantly evaluated markers of prognosis. Logistic regression showed that c Kit ranked 10 out of 25 (P=0.041), and was included in a 10-marker signature that allowed 79.2% of the patients to be correctly classified in the metastatic or metastasis-free categories independently of hormone receptors and HER-2 status. Interestingly, c Kit was also a significant predictor of metastasis in node-negative tumours (2 out of 25 ranking, P<0.0001) and included in a six-marker signature of prognosis, correctly classifying 88.6% of the patients (P<0.0001). CONCLUSION: We concluded that, as assessed by quantitative immunohistochemistry, c Kit is an independent prognostic indicator that could also potentially serve as a target for specific therapy in breast carcinomas.

c-Met overexpression in inflammatory breast carcinomas: automated quantification on tissue microarrays.

Inflammatory breast carcinoma (IBC) is a rare but aggressive tumour associated with poor outcome owing to early metastases. Increased expression of c-Met protein correlates with reduced survival and high metastatic risk in human cancers including breast carcinomas and is targetable by specific drugs, that could potentially improve the prognosis. In the present study, we compared c-Met expression in IBC (n=41) and non-IBC (n=480) immunohistochemically (Ventana Benchmark autostainer) in two tissue microarrays (TMA) along with PI3K and E-cadherin. The results were quantified through an automated image analysis device (SAMBA Technologies). We observed that (i) c-Met was significantly overexpressed in IBC as compared with non-IBC (P<0.001), (ii) PI3K was overexpressed (P<0.001) in IBC, suggesting that the overexpressed c-Met is functionally active at least through the PI3K signal transduction pathway; and (iii) E-cadherin was paradoxically also overexpressed in IBC. We concluded that overexpressed c-Met in IBC constitutes a potential target for specific therapy for the management of patients with poor-outcome tumours such as IBC. Automated image analysis of TMA proved to be a valuable tool for high-throughput immunohistochemical quantification of the expression of intratumorous protein markers.

Prediction of metastasis risk (11 year follow-up) using VEGF-R1, VEGF-R2, Tie-2/Tek and CD105 expression in breast cancer (n=905).

Neoangiogenesis in tumours contributes to the development of blood-borne metastases, and can be evaluated by markers of activated endothelial cells in preference to panendothelial markers. Our purpose was to document the prognostic significance of VEGF-R1, VEGF-R2, Tie-2/Tek and CD105 immunoexpression in breast carcinoma frozen samples (n=905, follow-up=11.7 years). We observed that: (i). CD105 (P=0.001) and Tie-2/Tek (P=0.025) (but not VEGF-R1 and VEGF-R2) overexpression correlated with a shorter survival, and were (Cox's model) independent histoprognostic indicators; (ii). only CD105 marked expression correlated (P=0.035) with a shorter survival of node-negative patients; (iii). three markers - CD105 (P=0.001), Tie-2/Tek (P=0.01), VEGF-R1 (P=0.001), but not VEGF-R2 - correlated with metastatic risk in node-negative patients in univariate analysis; and (iv). VEGF-R1 (P=0.01) expression correlated with high local recurrence risk. It is concluded that CD105 and to a lesser extent Tie-2/Tek and VEGF-R1, but not VEGF-R2 are endowed with prognostic significance that may be useful for patient monitoring, particularly CD105 expression for selecting node-negative patients for more aggressive postsurgery therapy.

Endometrial response to sexual steroids as assessed by prostaglandin F(2alpha) output in explant culture and hormone receptor expression.

The objective of this study was to evaluate the endometrial response to sexual steroids in organ culture using two means: prostaglandin (PG) F(2alpha) output in medium culture and steroid receptor immunoexpression in tissue. Human endometrium samples were classified in homogeneous and heterogeneous proliferative or secretory subsets. In proliferative endometrium explant culture, progesterone (10(-7) M) induced a significant decrease in PGF(2alpha) output, but this was not the case in secretory endometrium, whereas no significant effect of estradiol (10(-8) M) was observed. Before culture, homogeneous and heterogeneous proliferative endometrium presented the same pattern of estradiol receptor (ER) and progesterone receptor (PR) expression evaluated by quantitative immunocytochemistry. After culture, immunoreactive ER and PR were detected on the explant. PR immunoexpression rates after culture were lower than before culture in glands on homogeneous proliferative and in stroma on heterogeneous proliferative endometrium explants without in vitro steroid addition. In secretory endometrium, no significant difference was observed between ER or PR immunoexpression rates before culture and after culture. These results provided the hormonal receptivity status of endometrium after culture and will thus serve as a reference for evaluating in vitro steroid effects on endometrium explants. Our preliminary results suggest that cultures of endometrium explants are a valid model for studying the effects of hormonal treatment on homogeneous as well as heterogeneous endometrium. These data could be particularly relevant for evaluating the potential response to hormone stimulation and treatment of endometria sampled in perimenopausal patients.

E-cadherin and beta-catenin expression in breast medullary carcinomas.

The initial step of cancer invasion and metastasis is the escape of tumour cells from the primary site, involving disruption of normal cell-cell adhesion and E-cadherin (E-cad) and beta-catenin (beta-cat) down-regulation, as shown in various types of human malignancies including breast carcinomas. Medullary carcinomas are high grade and poorly differentiated tumours with syncytial typical pattern, and prognosis unexpectedly better than that in high grade breast carcinomas. In a series of 55 breast typical medullary carcinomas diagnosed according to the strict use of Ridolfi et al (Cancer 40: 1365-1385, 1977) criteria, E-cad and beta-cat were investigated using quantitative (SAMBA 2005 system) immunocytochemical assays on frozen sections. Results were compared to that obtained on paraffin sections and in a series (n=55) of grade 3 ductal carcinomas. It was shown that medullary carcinomas significantly (p<0.001) expressed more E-cad and beta-cat than grade 3 ductal carcinomas. E-cad and beta-cat correlated with high expression of P53, of c-erbB, and of Ki-67 antigens, and with lack of hormone receptors antigenic sites (p<0.001). It was concluded that favourable prognosis and syncytial pattern of typical breast medullary carcinomas likely results, at least partly, from a particular expression of cell-cell adhesion molecules, significantly limiting tumour growth and efficiently mastering the tumour cell dissemination, opposing to high proliferative activity (grade 3).

VCAM (IGSF) adhesion molecule expression in breast carcinomas detected by automated and quantitative immunocytochemical assays.

Expression of vascular cell adhesion molecules (VCAM) in tumors is associated with endothelial cell activation and may facilitate adherence of carcinomatous cells to the vessel wall, promoting bloodborne metastases. Expression of VCAM was investigated in 202 breast carcinomas using automated (Ventana System) and quantitative (SAMBA image analyzer) immunoperoxidase staining of frozen sections. Positive VCAM immunoreactivity was observed in 83 tumors (41%) (mean immunostained surface, 12.4%; SD, 10.5). The mean area of immunostaining was correlated with clinical and pathologic prognostic indicators and with the immunohistochemical expression in tissue sections of various indicators of cell proliferation, metastatic potential, and drug resistance or sensitivity, evaluated according to the same method. There was no correlation of VCAM immunoreactivity with tumor size, type, or grade or with nodal status. Also, no significant correlation was observed between VCAM and MIB1/Ki67, p53, Bcl-2, E cadherin, CD44v, cathepsin D, CD31, P-gp, ER, PR, or pS2. However, VCAM immunoreactivity was significantly correlated with ELAM and VLA2 (P = .001) and VLAs (P = .008) expression. The results suggest that VCAM expression in breast carcinoma tissue sections is likely not a prognostic indicator. Its practical clinical relevance, if any, must be established by correlation with patients' outcomes and tumor sensitivity to drugs.

VLA2 integrin expression in breast carcinomas evaluated by automated and quantitative immunohistochemistry.

VLA2 is thought to be involved in the metastatic process in malignant tumours, in particular in carcinomatous cell adhesion to vessel basement membrane. VLA2 expression was immunohistochemically investigated in 204 breast carcinomas. Frozen tissue sections were probed with monoclonal anti-VLA2 using automated (Ventana ES 320 System) and quantitative (SAMBA 2005 image processor) immunoperoxidase. A positive anti-VLA2 immunoreaction was observed in 48 tumours (23.5%), within epithelial carcinomatous cells. The VLA2-positive surface in tumours varied from 3% to 20% (mean 8.75, S.D. 7.17) and was correlated with histoprognostic indicators and tumour expression of various antigens detected using the same method as that for VLA2. The results show that VLA2 immunoexpression was independent of the tumour size, grade, type and aneuploidy, and of the nodal status. VLA2 significantly correlated with ELAM, VCAM, VLA3 and P-glycoprotein (P-gp) (P < 0.01) and inversely correlated with cathepsin D (P < 0.001), but was independent of Ki67/MIB1, p53, bcl-2, c-erbB-2, E cadherin, CD44v, CD31, oestrogen and progesterone receptors' (ER, PR) antigenic sites and pS2. The exact role, if any, of VLA2 in tumour cell dissemination remains to be elucidated and the clinical relevance of VLA2 immunodetection in breast carcinomas requires further investigation of the correlation between VLA2 immunocytochemical expression and patients' outcome and response to chemotherapy.

Prognostic significance of Nm23/NDPK expression in breast carcinoma, assessed on 10-year follow-up by automated and quantitative immunocytochemical assays.

The Nm23 gene has been described as an antimetastatic gene; in some studies, disease progression in patients with solid tumours is related to Nm23 protein expression, which can be detected by immunohistochemical procedures. Detection of Nm23-H1 protein in breast cancer may be relevant for the monitoring of patient therapy, provided that the technical procedures are reliable and cost-effective. The aim of the present study was to determine the prognostic significance of Nm23, assessed by quantitative immunocytochemical assays (Nm23 ICAs), under optimal technical conditions. Nm23-H1 ICAs were performed on frozen sections, using an automated immunoperoxidase technique (Ventana) and computer-assisted analysis of digitized colour microscopic images (SAMBA), in a series of 168 breast carcinomas. The results of automated quantitative ICAs were correlated with patients' follow-up (129 months). Nm23-H1 immunocytochemical expression in histological sections of tumours in which more than 3 per cent of the surface area was positively stained was significantly (0.012) correlated with longer metastasis-free survival in both node-positive and node-negative groups of patients (P = 0.032 and P = 0.036, respectively) (Kaplan-Meier log-rank test, NCSS 6.0.1 software). Nm23 expression (cut-point 3 per cent) did not, however, correlate with overall survival, or with the recurrence-free survival. In multivariate analysis (proportional hazards regression, Cox model), the prognostic significance of Nm23 in terms of metastasis-free survival was independent of tumour size and grade, and of histological grade, in the entire cohort of patients. It is concluded that Nm23 immunodetection is only of limited practical clinical relevance in breast carcinoma, even when assessed under optimal technical conditions.

[Prognostic value of E-cadherin expression in hepatocellular carcinoma]. / Valeur pronostique de l'expression de l'E-cadhérine dans les hépatocarcinomes.

Expression of E-cadherin (E-cad) was investigated immunohistologically in 91 cases of operated hepatocellular carcinomas. An alteration of E-cad immunodetection was found in 56% of tumours. These alterations were correlated with histopathologic features of prognostic value including tumour size (> 3 cm), high nuclear grade and mitotic index. Patients with down-regulated E-cad expression had statistically significant shorter survival than the others. Although E-cad immunodetection was an independent prognostic factor, the Cox multivariate analysis showed that its prognostic value was low when compared to other prognostic factors.

bcl-2 automated and quantitative immunocytochemical assays in breast carcinomas: correlation with 10-year follow-up.

PURPOSE: bcl-2 protein is detectable in human cancers and may be involved in the response to antineoplastic drugs or endocrine therapy in breast carcinomas. In a previous study, we had developed optimal technical conditions for bcl-2 immunodetection. The aim of the present report was to determine the prognostic significance of bcl-2 expression in breast carinomas by the use of a similar immunocytochemical procedure. METHODS: bcl-2 immunocytochemical assays were performed on frozen sections by automated immunoperoxidase technique (Ventana) and computer-assisted analysis of digitized colored microscopic images (SAMBA) in a series of 170 breast carcinomas. The results of automated quantitative immunocytochemical assays were correlated with patient follow-up (120 months). RESULTS: Intense bcl-2 immunocytochemical expression in tumors (cutpoint, 15%) significantly correlated with longer disease-free survival and longer recurrence-free survival in the entire cohort of patients (P = .028 and P = .035, respectively) and also in node-negative subgroups of patients (P = .028 and P = .01; Kaplan-Meier long-rank test; NCSS 6.0.1 software). But bcl-2 immunostained surfaces (cutpoint, 15%) did not correlate with overall survival. In multivariate analysis (proportional hazards regression, Cox model), bcl-2 prognostic significance in terms of disease-free survival was only independent of the tumor size and grade and histoprognostic index (Nottingham prognostic index [NPI]). CONCLUSION: bcl-2 immunohistochemical expression is a significant indicator of favorable outcome only in terms of disease-free and local recurrence-free survival. However, bcl-2 expression in tumors is an independent weakly prognostic indicator in breast carcinomas. bcl-2 immunodetection assessed in optimal technical conditions (frozen samples, automation, quantitative analysis, scatter diagram cutoffs) may have some limited practical clinical relevance for the management of patients with breast carcinomas.

ELAM selectin expression in breast carcinomas detected by automated and quantitative immunohistochemical assays.

ELAM is an E-Selectin adhesion molecule involved in the inflammatory process but it is also thought to potentially participate in the development of blood borne metastases, by facilitating tumour cell adhesion to vessels wall. ELAM expression in tumours was immunohistochemically investigated in 203 breast carcinomas. Frozen tissue sections were probed with monoclonal anti ELAM (Clone 1.2B6) using automated and quantitative immunoperoxidase systems. A positive anti-ELAM immunoreaction was observed in 113 tumours (57%). The mean surface of positive tumours varied from 3% to 50% (mean = 11.75%, SD = 8.7) and was correlated with histoprognostic indicators and tumour expression of various antigens detected according to the same method as ELAM. The results showed that ELAM immunoexpression was independent of the tumour size, grade and type and of the nodal status but significantly increased parallel to patients' age (p<0. 01). ELAM expression was independent of Ki-67/MIB1, anti-P53 and anti-Bcl2, anti-CD44v, anti-c-erbB-2, anti-CD31, anti-RE/RP, anti-PS2, and anti-VLA3 immunoreactions. But ELAM expression correlated with that of the VCAM vascular cell adhesion molecule (p=0.0004), VLA2 (p<0.0001), P-glycoprotein (p=0.025), and of Cathepsin D to a lower degree (p=0.06) and inversely correlated with E-cadherin (p=0.03). The results suggest that endothelial cell activation is independent of tumour cell proliferative activity and of stromal angiogenesis and that the precise role and regulation of ELAM in tumours remains to be elucidated. Also the clinical relevance of ELAM immunohistochemical expression requires further investigation and correlation with patients' follow-up.

Reduced E-cadherin immunohistochemical expression in node-negative breast carcinomas correlates with 10-year survival.

E-cadherin immunodetection was performed on frozen sections, using an immunoperoxidase procedure and with computer-assisted analysis of digitized colored microscopic images in a series of 179 breast carcinomas. Quantitative immunocytochemical assays were correlated with follow-up (129 months). The results showed that reduced E-cadherin immunocytochemical expression in tumors (cut point, 4%) significantly correlated with shorter overall survival in node-negative patients (Kaplan Meier log rank test). But E-cadherin immunostained expression (cut point, 4%) did not correlate with metastasis-free or recurrence-free survival. In multivariate analysis (Cox proportional hazards regression model), E-cadherin prognostic significance for overall survival in node-negative patients was independent of the tumor size, grade, and histologic type. The results suggest that reduced E-cadherin expression detected in optimum technical conditions (frozen samples and quantitative immunohistochemistry) is an independent indicator of poor survival in node-negative patients and may be clinically relevant for the treatment of patients with breast carcinomas.

Immunoexpression of E-cadherin and beta-catenin correlates to survival of patients with hepatocellular carcinomas.

Expression of E-cadherin (E-cad) and -catenin ( -cat) was investigated immunohistologically in 91 cases of excised hepatocellular carcinomas. Immunodectection was altered in 56% of tumours for E-cad and in 30.8% for -cat. Downregulation of E-cad and -cat correlated with the size of tumours, and high nuclear grade, but only E-cad alteration correlated with the mitotic index. Alterations of E-cad and -cat expression correlated with survival. Although E-cad and -cat immunodetections were independent prognostic factors, their prognostic value was lower than that of current clinicopathological parameters.

Automated and quantitative immunocytochemical assays of Nm23/NDPK protein in breast carcinomas.

A series for Nm23-protein immunodetection was investigated in human breast carcinomas. Frozen sections were processed by automated immunoperoxidase procedure, and immunoprecipitates in positive tumors were quantified by processing digitized microscopic images. Nm23 immunohistochemical expression in tumors was correlated with clinicopathological data and with intra-tumoral proteins also detected by automated and quantitative immunohistochemistry. A positive Nm23 immunoreaction was observed in 58% of tumors, within cell cytoplasm. Nm23 expression was independent of the patient's age, and of tumor size, type and grade, but an inverse relationship was observed between Nm23 expression and axillary-lymph-node metastasis. An inverse relationship was also observed between Nm23 and P-53, CD-31, cathepsin D, tenascin and P-gp immunohistochemical expressions. But Nm23 expression was independent of c-erb-B product, growth fraction (MIB1/Ki67), and immunohistochemical expression of hormone receptors/P-S2. The results suggest that the anti-metastatic nm23 gene may partly act upon the regulation of tumor-cell proliferation (correlation with P-53) and may have some effects on epithelial-cell/stroma interactions (regulation of extracellular-matrix protease and of angiogenesis) independently of hormone sensitivity.

CD31/PECAM automated and quantitative immunocytochemical assays in breast carcinomas: correlation with patient follow-up.

The purpose of this study was to determine the prognostic significance of quantitative CD31 immunohistochemical assays. CD31 assays were performed on a series of 167 breast carcinoma specimens under optimal technical conditions that involved frozen sections, an automated immunoperoxidase technique, and computer-assisted analysis of digitized colored microscopic images. Results of automated quantitative immunohistochemical assays were correlated with patient follow-up (9.6 years). Patients were divided into two subgroups: those who had axillary lymph node-positive (N+) disease and those who had lymph node-negative (N-) disease. The marked immunocytochemical expression of CD31 in tumors (cutoff point, 20%) was significantly (P = .033) associated with a poor overall survival rate (Kaplan-Meier, log rank test); however, a significant association was not observed in the N+ and N- subgroups. CD31-immunostained tumor cell surfaces larger than 20% correlated with the metastasis-free survival rate (P = .004) in all patients and in the N+ subgroup (P = .005) but not in the N- subgroup. In addition, marked immunocytochemical expression of CD31 correlated with the short-term disease-free survival rate (P = .04) in the N+ subgroup but not in the N- subgroup. In multivariate analysis (proportional hazards regression, Cox model) the prognostic significance of CD31 was independent of tumor size and histologic type but not of grade. The results suggest that, under optimal technical conditions (automated and quantitative immunohistochemical assays on frozen sections), immunohistochemical expression of CD31 is a significant prognostic indicator of overall and metastasis-free survival rates. CD31 has limited prognostic value, however, and is not a completely independent prognostic indicator because it is related to nodal status.

Automated and quantitative immunocytochemical assays of CD44v6 in breast carcinomas.

CD44 variants carrying sequences encoded by exon v6 are preferentially expressed in metastatic animal cancer cell lines. CD44v6 overexpression correlates tumor dedifferentiation and progression in some human carcinomas, but the relationship of CD44v6 overexpression with metastatic behavior of tumor observed in animal models is controversial, particularly in breast carcinomas. The discrepancies probably result from analytical bias. We investigated CD44v6 and CD44s expression in 218 frozen samples of primary breast carcinomas. Immunocytochemical procedure was performed under optimal technical conditions using commercially available 2F-10 monoclonal antibody (MAb), a microprocessor-controlled automated device (Ventana Medical Systems, Tucson, AZ), and quantitative evaluation of results by processing digitized-colored microscopic images (SAMBA, Grenoble, France). CD44v6 expression in tissue sections was shown to be independent of the patient age, tumor size, histological types and grades, and the lymph node status. CD44v6 expression was also independent of the expression of molecules endowed with poor prognostic significance detected by MAbs (anti-p53, anti-c-erb B-2 protein, MIB1) on consecutive sections. No significant relationship could be evidenced either between CD44v6 expression, and CD31 involved stromal angiogenesis and cathepsin D. Finally, CD44v6 was independent of markers of hormone dependence (estrogen and progesterone receptors, pS2) and of multidrug resistance (P-glycoprotein). Similar results were observed with anti-CD44s. We conclude that the true prognostic significance of CD44v6 overexpression still remains to be shown under rigorous technical conditions (frozen samples, well-documented MAbs, and optimal standardization of procedure using automation and quantitative analysis) providing data appropriate for further correlation with long-term patient follow-up.

c-erbB-2 oncoprotein detected by automated quantitative immunocytochemistry in breast carcinomas correlates with patients' overall and disease-free survival.

The prognostic significance of c-erbB-2 oncoprotein overexpression detected in tumours by immunocytochemical assays (ICAs) was investigated in 148 breast carcinomas. ICAs were performed under optimal technical conditions with frozen tissue sections and included automated immunoperoxidase technique and computer-assisted analysis (densitometry) of digitized coloured microscopic images. Results of quantitative ICAs (expressed in percentages of c-erbB-2-positive surfaces and mean optical densities) were correlated with the patients' follow-up in axillary lymph node-positive (N+) and node-negative (N-) subgroups of patients. Patients' follow-up ranged from 9 months (for the first death) to 101 months (for the 121 alive patients) with a 62.5 months mean overall follow-up. It was shown that marked c-erbB-2 immunocytochemical expression in tumours (cut-off point 35%) significantly correlated with the patients' poor overall survival in N+ and in N- patients (Kaplan-Meier, log-rank test, P = 0.045 and P = 0.015). Also, marked c-erbB-2 immunohistochemical expression correlates with short disease-free (P = 0.005), recurrence-free (P = 0.048) and metastasis-free survival (P = 0.05) (Kaplan-Meier, log-rank test) in N+, but not in N- subgroups. It is concluded that in optimal conditions (automated and quantitative ICAs on frozen sections) c-erbB immunohistochemical expression is a significant prognostic indicator in terms of overall and disease-free survival. The c-erbB-2 protein prognostic significance is independent of node status in terms of overall survival, but not of disease-free survival.

Automated and quantitative immunocytochemical assays of Bcl-2 protein in breast carcinomas.

Expression of the bcl-2 gene was investigated in 218 human breast carcinomas by immunohistochemical analysis. Immunodetections were assessed using (1) frozen sections, (2) documented commercially available monoclonal antibody (bcl-2/124, Dako), (3) automation of immunoperoxidase technique (Ventana) and (4) quantitative evaluation of results by image analysis (SAMBA) and statistical analysis of quantitative data (BMDP software). Bcl-2 protein expression was correlated with current prognostic indicators and with molecular markers detected by the same procedure as for Bcl-2. It was shown that Bcl-2 expression is not related to patients' age, tumour size and type or lymph node status, but an inverse relationship was observed between Bcl-2 and tumour grade (P < 0.0001). An inverse relationship was also observed between Bcl-2 expression and p53 (P < 0.0001), Ki67/MIB1 antigen- (P = 0.0012), and P-gp- (P = 0.002) positive immunoreactions. In contrast, anti-Bcl-2 positive reaction was significantly associated with ER-positive (P < 0.001) and with ER/PR-positive or ER/PR/pS2-positive immunoreactions (P < or = 0.005). Bcl-2 expression was independent of CD31 and cathepsin D expression. Thus, Bcl-2 protein, thought to be antiapoptotic, exhibits parodoxical expression in human breast carcinomas. It is strongly detected in low-grade tumours (well-differentiated) with low (MIB1) growth fraction, but is independent of the tumour progression (size, node status, CD31, and cathepsin D). Bcl-2 acting on apoptosis is related to p53 gene abnormalities in breast carcinomas. Bcl-2 protein expression may also be involved in response to endocrine therapy (associated to ER/PR/pS2 positive immunoreactions) and probably with chemoresistance mechanisms (inverse relationship with P-gp).

Quantitative immunocytochemical assays on frozen sections of p53: correlation to the follow-up of patients with breast carcinomas.

A series of 222 tumor samples stored at -80 degrees C in the authors' tumor library were investigated with anti-p53 (PA 1801) and streptavidin-biotin-peroxidase complex. The p53 immunoprecipitates were quantified by densitometry assessed by image analysis of digitized microscopic images. Two parameters, percentage of positive surface and mean optical densities, were compared with the patient's outcome (follow-up = 96.8 months) (life table method, Mantel Cox test, BMDP statistical software). The p53 expression significantly correlated with a poor overall survival (P = .0063), metastasis-free survival (P = .024), and recurrence-free survival (P = .022) at a 20% cutoff point of positive immunoreactive tumor surface. A strong prognostic significance was observed in the node-positive subset of patients but not in the node-negative subset, except for recurrence-free survival (P = .047). The results indicate the clinical relevance p53 evaluated by quantitative immunocytochemistry.