Proto-oncogene abnormalities in human breast cancer: correlations with anatomic features and clinical course of disease

Redox balance and autophagy regulation in cancer progression and their therapeutic perspective

Cellular ROS production participates in various cellular functions but its accumulation decides the cell fate. Malignant cells have higher levels of ROS and active antioxidant machinery, a characteristic hallmark of cancer with an outcome of activation of stress-induced pathways like autophagy. Autophagy is an intracellular catabolic process that produces alternative raw materials to meet the energy demand of cells and is influenced by the cellular redox state thus playing a definite role in cancer cell fate. Since damaged mitochondria are the main source of ROS in the cell, however, cancer cells remove them by upregulating the process of mitophagy which is known to play a decisive role in tumorigenesis and tumor progression. Chemotherapy exploits cell machinery which results in the accumulation of toxic levels of ROS in cells resulting in cell death by activating either of the pathways like apoptosis, necrosis, ferroptosis or autophagy in them. So understanding these redox and autophagy regulations offers a promising method to design and develop new cancer therapies that can be very effective and durable for years. This review will give a summary of the current therapeutic molecules targeting redox regulation and autophagy for the treatment of cancer. Further, it will highlight various challenges in developing anticancer agents due to autophagy and ROS regulation in the cell and insights into the development of future therapies.

Transcriptome Profile Analysis of Triple-Negative Breast Cancer Cells in Response to a Novel Cytostatic Tetrahydroisoquinoline Compared to Paclitaxel

The absence of chemotherapeutic target hormone receptors in breast cancer is descriptive of the commonly known triple-negative breast cancer (TNBC) subtype. TNBC remains one of the most aggressive invasive breast cancers, with the highest mortality rates in African American women. Therefore, new drug therapies are continually being explored. Microtubule-targeting agents such as paclitaxel (Taxol) interfere with microtubules dynamics, induce mitotic arrest, and remain a first-in-class adjunct drug to treat TNBC. Recently, we synthesized a series of small molecules of substituted tetrahydroisoquinolines (THIQs). The lead compound of this series, with the most potent cytostatic effect, was identified as 4-Ethyl-N-(7-hydroxy-3,4-dihydroisoquinolin-2(1H)-yl) benzamide (GM-4-53). In our previous work, GM-4-53 was similar to paclitaxel in its capacity to completely abrogate cell cycle in MDA-MB-231 TNBC cells, with the former not impairing tubulin depolymerization. Given that GM-4-53 is a cytostatic agent, and little is known about its mechanism of action, here, we elucidate differences and similarities to paclitaxel by evaluating whole-transcriptome microarray data in MDA-MB-231 cells. The data obtained show that both drugs were cytostatic at non-toxic concentrations and caused deformed morphological cytoskeletal enlargement in 2D cultures. In 3D cultures, the data show greater core penetration, observed by GM-4-53, than paclitaxel. In concentrations where the drugs entirely blocked the cell cycle, the transcriptome profile of the 48,226 genes analyzed (selection criteria: (p-value, FDR p-value < 0.05, fold change −2< and >2)), paclitaxel evoked 153 differentially expressed genes (DEGs), GM-4-53 evoked 243 DEGs, and, of these changes, 52/153 paclitaxel DEGs were also observed by GM-4-53, constituting a 34% overlap. The 52 DEGS analysis by String database indicates that these changes involve transcripts that influence microtubule spindle formation, chromosome segregation, mitosis/cell cycle, and transforming growth factor-β (TGF-β) signaling. Of interest, both drugs effectively downregulated “inhibitor of DNA binding, dominant negative helix-loop-helix” (ID) transcripts; ID1, ID3 and ID4, and amphiregulin (AREG) and epiregulin (EREG) transcripts, which play a formidable role in cell division. Given the efficient solubility of GM-4-53, its low molecular weight (MW; 296), and capacity to penetrate a small solid tumor mass and effectively block the cell cycle, this drug may have future therapeutic value in treating TNBC or other cancers. Future studies will be required to evaluate this drug in preclinical models.

Plasma C-MYC level manifesting as an indicator in progression of breast cancer

Aim: To investigate whether plasma C-MYC level could be an indicator in clinical progression of breast cancer. Materials & methods: Plasma level of C-MYC expression was detected by quantitative real time PCR and the level of c-myc protein in breast cancer tissues was detected by immunohistochemistry. The expression level of C-MYC mRNA in supernatant of cancer cells culture was measured compared with the nonbreast cancer cells. Results: Plasma C-MYC level was significantly higher in patients with breast cancer than that in the controls, which associated with clinical stages, lymph node status, etc. Receiver operating characteristic curve analysis showed the sensitivity and specificity of plasma C-MYC level for diagnosis of breast cancer were 63.6 and 81.8%, respectively. The expression of c-myc protein in breast cancer tissues was associated with plasma C-MYC level, even C-MYC level in supernatant of cancer cells was elevated. Conclusion: Plasma C-MYC level might be a potential indicator in progression of breast cancer.

Long-Term Survival and Prognostic Factors for 2170 Breast Cancer Patients Treated at Two Cancer Centers: (Milan and Houston)

Data on 2170 consecutive patients with breast cancer submitted to curative surgery with or without combined radiotherapy in the period 1968–1972 at the National Cancer Institute of Milan (Italy) and at the University of Texas M.D. Anderson Cancer Center of Houston (Texas, USA) were analyzed to evaluate the prognosis of breast cancer patients after loco-regional treatment only and to verify if different prognostic factors have the same relevance. Forty-four percent of patients were alive without evidence of disease at the end of the follow-up in both centers: 14% of patients treated in Milan died without evidence of breast cancer with an intercurrent disease, whereas the death rate for intercurrent disease was 27 % in Houston. Thirty-seven percent of the patients in Milan and 26% of the patients in Houston died from breast cancer. A considerable percentage of patients (23.4 % in Milano, 38.2% in Houston) had one or more of the required items not specified in the clinical chart. Since the lack of information was considered a possible source of bias, the series were divided into two groups: the first collecting patients with all information available, the second gathering patients with at least one of the required items missing. The latter group was defined « unknown ». Multivariate analysis of survival, carried out by means of Cox's regression model, showed that mortality of these patients for all causes was significantly affected by the following criteria: status of regional nodes (P = 2 × 10−18), unknown (P = 10−9), maximum diameter of primary tumor (P = 7 × 10−10), age of the patients (P = 10−4), site of primary (P = 0.01), and Center (P = 0.04). A significant interaction was found between center and a) age of the patients, b) menopausal status and c) unknown. The relative P values were 6 × 10−7 for age and center, 8 × 10−3 for menopausal and center, 3 × 10−2 for unknown and center. Multivariate analysis of breast cancer mortality was significantly affected by: status of regional nodes (P = 10−18), diameter of primary (P = 5 × 10−14), unknown (P = 2 × 10−13), center (P = 2 × 10−6), site of primary (P = 0.002), and age of the patients (P = 0.03). The same significant interaction as for mortality from all causes was found. It is concluded that comparability of results obtained in different institutions may be dependent on the standardization and availability of patients data. The lack of information may introduce considerable biases in the evaluation of results, as was shown by the relevance of the variable unknown on mortality for all causes and for breast cancer. As regards the number of positive lymph nodes as a criterion to define subgroups of patients with different risks of death, we were unable to identify a definite breaking point. The most widely used categorization of this variable (1–3 positive nodes and 4 or more positive) was not supported by our data.

Genomic Alterations in Human Breast Cancer: A Review

We review and discuss data on the genetic alterations documented in human breast carcinomas at the molecular level. These alterations may result in: 1) deletion of genetic material (chromosome 11p, 13q, 3p, 1q, 17p); 2) amplification of genes or entire chromosomal segments (c-myc, c-erb-B2, locus DF3/PUM, loci on 11q13); 3) rearrangements (c-myc); 4) point mutations (c-ras). Presently available informations do not allow the development of cohesive pathogenetic models but indicate that the molecular basis of human breast cancer is heterogeneous.

C-erbB-2 Expression in Primary Breast Cancer

c-erbB-2 is an oncoprotein which is overexpressed in up to 40% of primary breast cancers. c-erbB-2 overexpression is a bad prognostic factor in patients with lymph node-positive disease. Unfortunately, there has been no agreement to date on whether c-erbB-2 overexpression is of prognostic significance in patients with lymph node-negative disease. c-erbB-2 overexpression is correlated with the absence of estrogen receptor expression in a number of publications. Correlation between c-erbB-2 overexpression and hormone sensitivity in the clinical setting is less well established and is the focus of ongoing studies. Both preclinical and clinical studies support an association between c-erbB-2 receptor overexpression and resistance to alkylating agents. In contrast, the data for c-erbB-2 and anthracyclines should be viewed in a slightly different manner. Anthracyclines appear to have a greater therapeutic effect in c-erbB-2-positive disease which may be dose sensitive. In c-erbB-2-negative disease not only is the therapeutic effect reduced but there does not appear to be any improved response to higher doses of anthracyclines. The data for c-erbB-2 and the taxanes is still not clear enough to provide any definite conclusions. If there is a correlation it would at present appear to be between paclitaxel and response rates, but this needs to be confirmed in larger studies. Few studies have looked at changes in c-erbB-2 on therapy. Those that have seem to show no significant change on either tamoxifen or chemotherapy.

"Triple negative breast cancer": Translational research and the (re)assembling of diseases in post-genomic medicine

The paper examines the debate about the nature and status of "Triple-negative breast cancer", a controversial biomedical entity whose existence illustrates a number of features of post-genomic translational research. The emergence of TNBC is intimately linked to the rise of molecular oncology, and, more generally, to the changing configuration of the life sciences at the turn of the new century. An unprecedented degree of integration of biological and clinical practices has led to the proliferation of bio-clinical entities emerging from translational research. These translations take place between platforms rather than between clinical and laboratory settings. The complexity and heterogeneity of TNBC, its epistemic and technical, biological and clinical dualities, result from its multiple instantiations via different platforms, and from the uneven distribution of biological materials, techniques, and objects across clinical research settings. The fact that TNBC comes in multiple forms, some of which seem to be incompatible or, at least, only partially overlapping, appears to be less a threat to the whole endeavor, than an aspect of an ongoing translational research project. Discussions of translational research that rest on a distinction between basic research and its applications fail to capture the dynamics of this new domain of activity, insofar as application is built-in from the very beginning in the bio-clinical entities that emerge from the translational research domain.

Prognostic/Predictive Factors in Breast Cancer

This can be an exciting time for pathologists and cytopathologists as we refine or knowledge of prognostic/predictive factors in breast cancer. We can become more visible in our role as consultants to the other physicians, and more engaged in our role as re-searchers. Recent advances in computer science, coupled with the availability of new biological markers, now provide unique opportunities for us to expand our diagnostic abilities and also predict the biologic behavior of a given tumor. Thus, we must become more familiar with emerging concepts and technologies in different disciplines.

C-myc amplification in breast cancer: a meta-analysis of its occurrence and prognostic relevance

Data from basic research suggests that amplification of the proto-oncogene c-myc is important in breast cancer pathogenesis, but its frequency of amplification and prognostic relevance in human studies have been inconsistent. In an effort to clarify the clinical significance of c-myc amplification in breast cancer, we conducted a comprehensive literature search and a meta-analysis in which 29 studies were evaluated. The weighted average frequency of c-myc amplification in breast tumours was 15.7% (95% CI = 12.5-18.8%), although estimates in individual studies exhibited significant heterogeneity, P<0.0001. C-myc amplification exhibited significant but weak associations with tumour grade (RR = 1.61), lymph-node metastasis (RR = 1.24), negative progesterone receptor status (RR = 1.27), and postmenopausal status (RR = 0.82). Amplification was significantly associated with risk of relapse and death, with pooled estimates RR = 2.05 (95% CI = 1.51-2.78) and RR = 1.74 (95% CI = 1.27-2.39), respectively. This effect did not appear to be merely a surrogate for other prognostic factors. These results suggest that c-myc amplification is relatively common in breast cancer and may provide independent prognostic information. More rigorous studies with consistent methodology are required to validate this association, and to investigate its potential as a molecular predictor of specific therapy response.

Oncogenes and male breast carcinoma: c-erbB-2 and p53 coexpression predicts a poor survival

PURPOSE

To investigate the prognostic value of biomarkers in male breast carcinoma (MBC).

PATIENTS AND METHODS

Fifty patients (mean age, 62.2 years) with invasive ductal carcinoma were retrospectively studied. All patients received surgery; 35 had adjuvant postoperative therapy. The median follow-up was 59 months (range, 1 to 230 months). c-myc, c-erbB-2, p53, and bcl-2 proteins were immunohistochemically detected on sections from formalin-fixed, paraffin-embedded tissues using 9E11, CB11, DO7, and bcl-2 124 monoclonal antibodies (mAbs). Estrogen, progesterone, and androgen receptors were detected using specific mAbs. Cell proliferation was assessed by MIB-1 mAb.

RESULTS

In univariate analysis, c-myc, c-erbB-2, and p53 protein overexpression was significantly correlated with prognosis. The median survival was 107 months for c-myc-negative and 52 months for c-myc-positive patients (P =.01), 96 months for c-erbB-2-negative and 39 months for c-erbB-2-positive patients (P =.02), and 100 months for p53-negative and 33 months for p53-positive patients (P =.0008). Tumor histologic grade (P =.01), tumor size (P =.02), patient age at diagnosis (P =.03), and MIB-1 scores (P =.0004) also had prognostic value. In multivariate analysis, only c-erbB-2 and p53 immunoreactivity retained independent prognostic significance. All nine patients who did not express c-erbB-2 and p53 proteins were alive after 58 months, whereas none of the 14 patients expressing both proteins survived at 61 months follow-up (P =.0002).

CONCLUSION

Overexpression of c-myc, c-erbB-2, and p53 proteins may be regarded as an additional prognostic factor in MBC. The combination of c-erbB-2 and p53 immunoreactivity can stratify patients into different risk groups.

Role of HER2 gene overexpression in breast carcinoma

The HER2 proto-oncogene encodes a transmembrane glycoprotein of 185 kDa (p185(HER2)) with intrinsic tyrosine kinase activity. Amplification of the HER2 gene and overexpression of its product induce cell transformation. Numerous studies have demonstrated the prognostic relevance of p185(HER2), which is overexpressed in 10% to 40% of human breast tumors. Recent data suggest that p185(HER2) is a ligand orphan receptor that amplifies the signal provided by other receptors of the HER family by heterodimerizing with them. Ligand-dependent activation of HER1, HER3, and HER4 by EGF or heregulin results in heterodimerization and, thereby, HER2 activation. HER2 overexpression is associated with breast cancer patient responsiveness to doxorubicin, to cyclophosphamide, methotrexate, and fluorouracil (CMF), and to paclitaxel, whereas tamoxifen was found to be ineffective and even detrimental in patients with HER2-positive tumors. In vitro analyses have shown that the role of HER2 overexpression in determining the sensitivity of cancer cells to drugs is complex, and molecules involved in its signaling pathway are probably the actual protagonists of the sensitivity to drugs. The association of HER2 overexpression with human tumors, its extracellular accessibility, as well as its involvement in tumor aggressiveness are all factors that make this receptor an appropriate target for tumor-specific therapies. A number of approaches are being investigated as possible therapeutic strategies that target HER2: (1) growth inhibitory antibodies, which can be used alone or in combination with standard chemotherapeutics; (2) tyrosine kinase inhibitors (TKI), which have been developed in an effort to block receptor activity because phosphorylation is the key event leading to activation and initiation of the signaling pathway; and (3) active immunotherapy, because the HER2 oncoprotein is immunogenic in some breast carcinoma patients.

MYC oncogenes and human neoplastic disease

c-myc, N-myc and L-myc are the three members of the myc oncoprotein family whose role in the pathogenesis of many human neoplastic diseases has received wide empirical support. In this review, we first summarize data, derived mainly from non-clinical studies, indicating that these oncoproteins actually serve quite different roles in vivo. This concept necessarily lies at the heart of the basis for the observation that the deregulated expression of each MYC gene is reproducibly associated with only certain naturally occurring malignancies in humans and that these genes are not interchangeable with respect to their aberrant functional consequences. We also review evidence implicating each of the above MYC genes in specific neoplastic diseases and have attempted to identify unresolved questions which deserve further basic or clinical investigation. We have made every attempt to review those diseases for which significant and confirmatory evidence, based on studies with primary tumor material, exists to implicate MYC members in their causation and/or progression.

Immunohistochemical expression of c-erbB-2 oncoprotein and EGF-R in pre- and postmenopausal breast cancer

Tissues from 40 cases each of premenopausal and postmenopausal breast cancer were studied immunohistochemically for epidermal growth factor receptor (EGF-R) and c-erbB-2 oncoprotein. In the premenopausal group, immunopositivity for c-erbB-2 was 15% and for EGF-R 22.5%, whereas in the postmenopausal group, 45% of cases were positive for c-erbB-2 and 42.5% for EGF-R. The difference in immunoexpression of c-erbB-2 between the two groups was significant. A significant correlation was observed between the concomitant expression of c-erbB-2 as well as EGF-R and lymph node involvement. Furthermore, an association was found between c-erbB-2 positivity and histological grading of the tumour. It is interesting that the pattern of the investigated parameters indicates the difference in the pathological events of pre- and postmenopausal breast cancer.

ERBB2 oncogene in human breast cancer and its clinical significance

We reveiwed the relationships between ERBB2 amplification and/or overexpression in human breast cancer and the clinicopathological parameters described in the literature (97 studies involving 22,616 patients) in order to draw conclusions regarding its clinical interest. The mean of ERBB2 positivity (26%, ranging from 5 to 55%) is not dependent on the method used to evaluate ERBB2 amplification or overexpression. Despite the discrepancies observed between the different studies, several associations between ERBB2 positivity and the classical clinicopathological parameters were noted. There are clear relationships between ERBB2 positivity and the lack of steroid receptors, the histological subtypes of mammary tumours (ductal invasive and in situ), worse histological and nuclear grades, aneuploidy and high rate of proliferation. In univariate analyses, ERBB2 is strongly associated with poor prognosis. All these data indicate that ERBB2 is a marker of aggressiveness of the tumour. However, ERBB2 does not retain a clinical prognostic significance in multivariate analyses, since it is associated with several strong prognostic parameters. When considering the prognostic value of ERBB2 in relation to treatment, a significantly worse survival of the treated patients is noted in ERBB2 positive patients. This suggest that ERBB2 could be a marker of reduced response to chemotherapy and hormonal treatment. With respect to the tumour response to treatment, the results, provided as yet by pilot studies, remain controversial and further investigations are necessary to evaluate the predictive value of ERBB2. Finally, new therapeutic approaches targeting the cells overexpressing ERBB2 have been developed.

Defining a role for c-Myc in breast tumorigenesis

The proto-oncogene c-myc is commonly amplified and overexpressed in human breast tumors, and the tumorigenic potential of c-myc overexpression in mammary tissue has been confirmed by both in vitro and in vivo models of breast cancer. However, the mechanisms by which Myc promotes tumorigenesis are not well understood. Recent evidence indicates that Myc can promote cell proliferation as well as cell death via apoptosis. These studies provide new insight and impetus in defining a role for c-Myc in breast tumorigenesis and may point toward novel targets for breast cancer therapy.

The relationship between flow-cytometric and immunohistochemically detected c-erbB-2 expression, grade and DNA ploidy in breast cancer

Quantification of c-erbB-2 and its relationship with other prognostic markers using flow cytometry has been examined. In this study a level for c-erbB-2 expression above which tumours are classified as positive by flow cytometry has been determined by employment of positive cut-off threshold levels. c-erbB-2 expression by both flow cytometry and immunohistochemistry was studied using the monoclonal antibody NCL-CBII. The relationship of c-erbB-2 quantification by flow cytometry was then compared with ploidy, axillary node status, tumour size and grade. Increased c-erbB-2 expression was seen using flow cytometry. Correlation between immunohistochemistry and flow-cytometry methods just failed to reach significance (P = 0.06). Immunohistochemistry revealed a significant relationship between c-erbB-2 expression and aneuploidy (P = 0.04). Cytokeratin-positive cells from 110 samples obtained from patients with breast cancer were assayed for DNA content and c-erbB-2 expression by flow cytometry. No correlation was seen between these parameters upon application of Mann Whitney analysis. However, examination of fluorescence thresholds showed a positive correlation between grade and c-erbB-2 expression at a level of more than 3200 molecules (P < or = 0.03). At the level of 3600 molecules significance was increased (P = 0.004). These levels equated with between 15% and 19% of the samples being classified as c-erbB-2-positive. Application of these cut-off points showed no correlation between c-erbB-2 expression and ploidy, tumour size or axillary node status. Comparison of ploidy and grade showed a significant association (P = 0.0015), increased grade correlating with aneuploidy.

Prognostic indicators for neuroblastoma: stage, grade, DNA ploidy, MIB-1-proliferation index, p53, HER-2/neu and EGFr--a survival study

Neuroblastoma, a tumor of the sympathetic nervous system, is one of the most common solid malignancies in infants and represents 7% of all cases of childhood cancer outside of the central nervous system. Thirty-five samples of neuroblastoma from 31 patients were obtained from Duke University Medical Center between 1979 and 1991 and studied to determine the relative prognostic value of a number of clinical, histologic, nuclear, and oncogenic features. The features studied were: stage, Shimada classification, DNA ploidy, MIB-1-proliferation index and status for HER-2/neu, p53 and epidermal growth factor receptor (EGFr). Only age (P = .03), HER-2/neu (P = .01), and p53 (P = .02) reached statistical significance as prognostic indicators. The median survival for patients with HER-2/neu expression was 12 months; median survival for patients with no HER-2/neu expression was 138 months. Similarly, the median survival for patients with p53 expression was 12 months; patients with no p53 expression had a median survival was 144 months. The combination of either HER-2/neu or p53 positivity was especially strong as a prognostic indicator (P = .002).

Comparison of immunoreactivity of neu oncoprotein in fine-needle aspirates and paraffin-embedded materials

Expression of the neu oncogene has been extensively examined in frozen and paraffin section breast cancers; however, very few studies examine neu oncoprotein oncoprotein expression in fine-needle aspirates. To this effect, we compared the expression of neu oncoprotein in formalin-fixed paraffin-embedded breast cancers and the corresponding fine-needle aspirates of these cancers. There was 100% correlation between the expression of neu oncoprotein in the paraffin-embedded breast cancers and the fine-needle aspirates, indicating the suitability of fine-needle aspirates for the expression of neu oncoprotein in breast cancers.

Soluble c-erbB-2 fragment in serum correlates with disease stage and predicts for shortened survival in patients with early-stage and advanced breast cancer

Seventy-nine patients with advanced breast cancer were tested for the presence, in serum, of a 110 kDa soluble, c-erbB-2 fragment. Thirty-nine patients were seropositive. There was no correlation between seropositivity and menopausal status, or with oestrogen status. In addition, no correlation could be found between tissue c-erbB-2 immunostaining for the external domain of the c-erbB-2 receptor and the presence of soluble c-erbB-2 in serum. The presence of serum soluble c-erbB-2, however, had a significant impact on survival of patients with advanced disease, suggesting that this test may become a useful independent prognostic indicator.

Estradiol receptors in combination with neu or myc oncogene amplifications might define new subtypes of breast cancer

Amplifications of neu and c-myc were evaluated in 218 and 145 breast cancers (BC), respectively. Oncogene amplifications were determined for the most part by Southern blot. An association between the proportion of nodes affected and the intensity of neu amplification in estadiol receptor negative (ER-) BC was found (P = 0.028), which was confirmed by the multi-factor analysis of variance (P = 0.05). A significantly greater incidence in neu amplifications among BC with metastases was also found (P = 0.031). A strong association (P = 0.01) between the neu and myc amplification was observed. There is a strong association between myc amplification and ER- BC (P < 0.01). It is concluded that (1) the combination ER- with neu amplification might define a new group of more aggressive BC, as is suggested by their associated nodal involvement; (2) the linkage of myc amplifications with ER- BC and high grade of neu amplification might reflect a trait of tumor aggressivity.

Is c-erb B-2 a predictor for recurrent disease in early stage breast cancer?

PURPOSE

To assess the prognostic importance of c-erb B-2 expression in early stage breast cancer.

METHODS AND MATERIALS

Immunohistochemical analysis for c-erb B-2 over-expression was retrospectively performed on 107 paraffin-embedded specimens of women with Stage I or II breast cancer entered in a randomized trial. Results were correlated with known prognostic factors such as pathologic axillary involvement, T-size, estrogen and progesterone receptor status, and nuclear grade. Immunohistochemical staining for c-erb B-2 protein expression was also correlated with breast/chest wall failure as well as survival without evidence of disease (NED) and overall survival.

RESULTS

C-erb B-2 overexpression was positive in 21% of the biopsy specimens. A significant association was found between c-erb-2 positivity and lesions containing an intraductal component, with 62% of lesions staining positively for c-erb B-2 having an intraductal component compared to only 36% of lesions with an intraductal component staining negatively for the c-erb B-2 protein (p2 = .031). A significant correlation between c-erb B-2 protein over-expression and axillary nodal status, primary tumor size, nuclear grade, and estrogen and progesterone receptor status was not identified. Cox proportional hazards model did not show a significant effect of c-erb B-2 expression for NED or overall survival.

CONCLUSION

Our study did not find over-expression of c-erb B-2 to reliably predict for recurrent disease in early stage breast cancer. This data can be added to other series comparing erb B-2 expression and disease outcome among node-positive and node-negative women with carcinoma of the breast.

Allele loss and point mutation in codons 12 and 61 of the c-Ha-ras oncogene in carcinogen-transformed human breast epithelial cells

There is significant evidence that the ras oncogene plays a role in experimental mammary carcinogenesis; the evidence in human breast cancer, however, is more limited. We induced the expression of transformation phenotypes in the human breast epithelial cell line MCF-10F with the chemical carcinogens 7,12-dimethylbenz[a]anthracene, N-methyl-N-nitrosourea, N-methyl-N-nitro-N'-nitrosoguanidine, and benzo[a]pyrene. This work was designed to clarify whether chemically induced neoplastic transformation correlates with alterations in the ras gene. MCF-10F cells have two c-Ha-ras alleles, identified by 1.0-kb and 1.2-kb restriction fragments. Treatment with carcinogens resulted in the loss of one of the alleles (1.0 kb). Polymerase chain reaction-amplified DNA from all carcinogen-treated cells was analyzed for point mutations in c-Ha-ras at codons 12 and 61. All of the carcinogens induced a mutation of the remaining allele at the first position of codon 12 (GGC-->AGC). Another frequent mutation occurred at the first position of codon 61 (CAG-->GAG). The changes in c-Ha-ras were associated with the emergence of colony formation in agar-methocel, but no specific changes in this gene correlated with the emergence of invasiveness or tumorigenesis, indicating that other genes may be involved in the process.

What's new in breast cancer? Molecular perspectives of cancer development and the role of the oncogene c-erbB-2 in prognosis and disease

The oncogene c-erbB-2 is frequently amplified in human breast carcinoma. The c-erbB-2 gene is present as a single copy in normal cells, and has been mapped to chromosome 17 in the region 17q 12-21.32. c-erbB-2 encodes a transmembrane glycoprotein known as p185. The intracellular component of p185 has tyrosine kinase activity; the extracellular domain has a structure resembling a growth factor receptor. c-erbB-2 amplification, p185 overexpression and levels of transcribed c-erbB-2 specific messenger RNA have been studied in a large number of breast carcinomas using a variety of techniques. In general, overexpression of p185 oncoprotein reflects various levels of DNA amplification, though in some cases amplification can be detected in the absence of overexpression of p185 and similarly overexpression of p185 can be present without detectable levels of c-erbB-2 amplification. This findings suggests that multiple mechanisms may be responsible for overexpression. c-erbB-2 amplification and/or overexpression occurs in almost all cases of high grade duct carcinoma in-situ, but has been reported in only 10%-40% of infiltrating duct carcinoma. c-erbB-2 amplification or overexpression occurs rarely in invasive lobular carcinoma, and has not been detected in ductal or lobular epithelial hyperplasia, or in atypical ductal or atypical lobular hyperplasia. It is generally believed that c-erbB-2 amplification/overexpression is an important independent prognostic indicator in breast carcinoma, identifying a subset of patients with poor prognosis tumours, particularly if axillary node metasases are present. However, many unanswered questions remain regarding c-erbB-2 and its role in breast cancer development and progression. The causes of c-erbB-2 amplification are unknown. There is no evidence of mutations in the human gene which might cause amplification or overexpression. The significance of the differences in levels of c-erbB-2 amplification/overexpression in in-situ duct carcinoma and associated invasive duct carcinoma has not been established. Amplification or overexpression have not been reported in atypical duct hyperplasia, a proposed precursor of duct carcinoma in-situ, yet overexpression occurs almost always in high grade duct carcinoma in-situ. c-erbB-2 may play a critical role in the development of a clonal in-situ, proliferation of high histological grade, yet does not obviously influence the acquisition of an invasive phenotype. We would postulated that this instability in amplification/overexpression is of biological significance, and if better understood may aid in the study of progression of human breast carcinoma.

Concurrent abnormal expression of ERBB-2, EGFR, and p53 genes and clinical disease progression of breast carcinoma

Metastatic phenotype in human solid tumors is believed to follow stochastic acquisition of structural genetic aberrations-so-called multistep tumor progression. We tested this hypothesis in breast carcinoma by immunostaining 89 stage-heterogeneous cases for the products of three genes (p53, ERBB-2, and EGFR) which are frequently altered in this tumor system. Variable relationships were observed between advanced disease stage and immunostaining for individual gene products (ERBB-2 - p = 0.05, EGFR - p = 0.02, p53 - p = 0.12, Chi Square test). Regional or distant metastases at presentation correlated with multiple oncogene/tumor suppressor gene expression abnormalities: node negative -59% none positive, 29% one positive, 12% two or more positive, vs. node positive -37% none positive, 23% one positive, 39% two or more positive (p = 0.01). Only 2/12 (17%) of tumors with distant metastases at presentation were negative for abnormal expression of any of these gene products, and 7/12 (58%) were positive for two or three. Among axillary node negative patients who developed recurrences, 67% exhibited staining for at least one gene product, compared to only 27% of those without recurrences (p = 0.02). All 5 cases with abnormal staining for each gene product had regional or distant metastases at presentation and recurred. In multivariate analysis, individual expression of p53 outweighed expression of ERBB-2 and EGFR in correlation with outcome. These data suggest clinical neoplastic progression of breast carcinomas correlates with cumulative genetic events detectable by protein expression. Short term recurrence, however, may correlate more closely with abnormal expression of p53 than with EGFR or ERBB-2.

The neu-oncogene product in serum and tissue of patients with breast carcinoma

BACKGROUND

A soluble 105 kD neu-related protein is detectable in conditioned medium from breast cancer cells expressing the neu-oncogene product and in serum of nude mice bearing tumors that overexpress neu-oncogene.

PATIENTS AND METHODS

In 100 patients with primary (n = 33) relapse-free (n = 6) and metastatic (n = 61) breast carcinoma the serum levels of the soluble neu-related protein were investigated by ELISA techniques. Median age was 57 years, range 26-89 years.

RESULTS

The neu-protein serum levels were below 40 HNU/ml (human neu-antigen unit) in 72 patients and 40 or more HNU/ml in 28 patients. In 30 patients with primary breast carcinoma, tested before mastectomy, all serum-neu-protein samples were negative. However, 26 of 61 metastasized patients (43%) were serum-neu-protein-positivity. In disseminated disease (n = 61), serum-neu-protein-positivity was more likely to be seen in patients with visceral metastases (18/33 = 54%), than in patients with nonvisceral metastases (8/28 = 28%). Furthermore, monitoring of the serum-neu-protein levels reflected clinical course. For 53 patients original paraffin-embedded tumor material was available for studying immunohistochemical neu-protein expression. In 39/53 (73%) patients immunohistochemical and ELISA data showed corresponding results. In 27/30 (90%) patients, from whom sera and tissue could be obtained at the same time at primary mastectomy, results of immunohistochemistry in primary tumor and serum ELISA were negative and mutually confirmatory. However, the other three patients were positive for immunohistochemical neu-protein expression in primary tumor but negative for serum-neu-protein expression.

CONCLUSIONS

Our results suggest that patients with advanced breast cancer and an elevated serum-neu-protein level may have a poor clinical outcome. This test might be a useful tool for monitoring patients with advanced breast carcinoma, but not those with early disease. Further prospective studies are warranted to elucidate the question of whether this test can contribute to determining prognosis and treatment strategies.

Lack of prognostic value of immunoreactivity for p62 oncoprotein in colorectal carcinoma

Immunohistochemical staining for c-myc p62 oncoprotein (p62) was performed in 59 colorectal carcinomas using mouse monoclonal antibody against human c-myc protein (MYC1-6E10). The immunoreactivity for p62 was intense in 22 (37.3%), and weak in 37 (62.7%) of the tumors. Advanced disease and nodal metastasis were more frequently seen in tumors showing intense staining but the difference did not reach statistical significance. Sixteen patients have died of the disease but overall survival rates did not differ between patients with tumors showing intense staining and those with tumors showing weakly staining. In 50 patients undergoing grossly curative resection, local or distant metastasis developed in 15 patients. Immunoreactivity for p62 had no effect on the rate of recurrence or disease free survival rates in these 50 patients undergoing grossly curative resection. The present study revealed that the immunoreactivity for p62 had no prognostic value in colorectal carcinoma.

An immunohistochemical and molecular biological study of c-erbB-2 amplification and prognostic relevance in gallbladder cancer

Forty-three cases of gallbladder cancer were investigated for c-erbB-2 gene amplification and c-erbB-2 protein over-expression using a combined polymerase chain reaction (PCR) and immunohistochemical approach. Thirty out of 43 cases (69.6%) demonstrated c-erbB-2 gene amplification, the positive rates being 50% and 77.4% for twelve early cancers and thirty-one advanced cancers, respectively (P < 0.05). However, there was no statistically significant correlation between c-erbB-2 gene amplification and histologic grade of differentiation or lymph node metastasis. Fourteen out of 43 cases (32.6%) showed positive immunoreactivity reflecting c-erbB-2 protein over-expression but again no statistically significant correlation was found with grade of differentiation, invasion or lymph node metastasis. Neither the c-erbB-2 gene nor the protein revealed any close relation to prognosis. In contrast, histopathologic findings for histologic grade of differentiation, invasion grade and lymph node metastasis showed good correlations to prognosis and between themselves. In conclusion, while c-erbB-2 gene and protein in gallbladder cancers might be related to invasiveness, they are not applicable as predictive factors for prognosis.

Prognostic indicators in early breast cancer

Approximately 115,000 new cases of axillary node negative breast cancer were diagnosed in this country last year. Since about 20-30% of these patients will ultimately relapse and die of their disease, adjuvant systemic therapy has been advocated for this group to decrease the relapse rate and prolong survival. However, although most clinical trials have demonstrated a modest impact on disease recurrence, the available data have failed to show consistent improvements in overall survival and does not justify the generalized use of systemic treatment in this patient subgroup. For this reason, a plethora of prognostic factors have been described to identify those patients with a higher risk of recurrence to concentrate therapeutic options in this specific group. Of all the disease prognosticators studied, tumor size, nuclear grade, and proliferative indexes appear to correlate well with tumor recurrence. In addition, biologic characteristics of primary tumors such as the presence of hormone and growth factor receptors, secretion of specific polypeptides and proteases, expression of proto-oncogenes, and abnormalities in tumor suppressor genes have been shown to be potentially useful as prognostic indicators in patients with early breast cancer. Despite these provocative data, larger clinical trials are necessary before incorporating these parameters in the routine evaluation of patients with axillary node negative breast cancer.

Prognostic significance of c-erbB-2 expression in node negative breast cancer

The prognostic value of c-erbB-2 oncogene expression was studied retrospectively in a consecutive series of 230 node negative breast cancers, followed-up for at least 7 years after primary treatment. The expression of c-erbB-2 oncoprotein was determined on formalin-fixed paraffin-embedded tissue, using a monoclonal anti-c-erbB-2 antibody by the avidin-biotin immunoperoxidase method. Positive immunostaining was observed in 20.9% of cases, whereas strong diffuse positivity was recorded only in 8.7% of cases. C-erbB-2 gene product showed no association to T category or nuclear grade. A significant association of c-erbB-2 expression to prognosis was observed only for cases showing a strong diffuse immunostaining, but such an association was no longer statistically significant at multivariate analysis adjusting for other prognostic factors such as T category and nuclear grading. C-erbB-2 expression is of no value to predict the clinical course of node negative patients in the current practice.

Tyrosine kinase receptor--nuclear protooncogene interactions in breast cancer

In summary, evidence is beginning to accumulate in support of a major role for tyrosine kinase receptors (and their activating growth factors) and steroid hormones and their receptors in normal development and differentiation of the mammary gland. A point of intersection of their mechanisms of action in growth control appears to be the induction of nuclear protooncogenes such as c-myc. When c-myc is amplified, as it is in many breast cancers, EGF and FGF receptor tyrosine kinase action becomes transforming, not simply mitogenic. A source of the transforming factors could be either stromal or epithelial. This mechanism could function early in the progression of breast cancer. c-erbB-2 and EGF receptor overexpression and amplification, when they occur, appear to render tumors even more malignant and of especially poor prognosis. These mechanisms could function late in the progression of breast cancer. Transgenic mouse studies have begun to echo these themes. They have established that a growth factor (TGF-alpha) and its receptor (EGF receptor), which appear to be important in normal mouse and human proliferation and gland development, and a protooncogene (c-myc), commonly amplified and overexpressed in human and mouse breast cancer, can each contribute to mammary carcinogenesis. The mechanisms of the two are likely to be distinct. myc is likely to be acting as a tumor initiator in combination with normal proliferative factors, whereas TGF-alpha is likely to be acting as a hyperproliferative (promotional) factor in combination with a normal background of mutational events. The role of unmutated but amplified erbB-2 in the transgenic mouse is not yet known.

Steroid hormone receptor immunohistochemistry and amplification of c-myc protooncogene. Relationship to disease-free survival in breast cancer

BACKGROUND

It is important to develop parameters that aid in prognosticating which patients with breast cancer are more likely to have a rapid disease course and therefore might benefit from early aggressive therapies.

METHODS

Specimens from two groups of women, deliberately selected because their clinical courses differed greatly, were studied to detect amplification of the protooncogenes c-myc, int-2, and C-erbB-2/neu by slot-blot assay, the estrogen receptor (ER), and the progesterone receptor (PR) by both biochemical and immunohistochemical procedures (ERICA and PRICA). One group of 50 patients had a prolonged disease-free interval after initial surgery (mean, 6.4 years); the other group of 52 women had had rapid disease recurrence (mean, 1.4 years) or progression (5 patients died of disease within 1 year of diagnosis). The patients were selected from 1700 consecutively accessioned cases if they fit the study criteria and sufficient tissue was available for oncogene hybridization studies.

RESULTS

The two groups differed statistically by stage, number of involved axillary lymph nodes, ERICA and PRICA results (P = 0.001), and amplification of c-myc (P = 0.003). The percentage of patients with rapid disease recurrence and progression increased from 0-93% when risk factors changed from best case (ERICA and PRICA results, positive; c-myc, not amplified; and axillary nodes, not involved) to worst case (ERICA and PRICA findings, negative; c-myc, amplified; and axillary nodes, involved).

CONCLUSIONS

Women with these worst-case parameters were more likely to have a recurrence sooner and rapidly progressive disease. They might benefit from early aggressive therapeutic measures.

Activated oncogenes and putative tumor suppressor genes involved in human breast cancers

Cytogeneticists first proposed that the karyotypic abnormalities identified on chromosomes 1, 3, 6, 11, 13, 16, 17, and 18 supported a genetic basis for breast cancer. Such abnormal banding patterns, however, may represent either loss-of-function or gain-of-function molecular events. RFLP analyses have since confirmed that 20-60% of primary and spontaneous human breast tumors exhibit allelic losses on these same chromosomes, although the exact genes involved at these chromosomal sites remain largely unknown. Knowledge gained about the Rb-1 and p53 tumor suppressor genes at 13q14 and 17p13 in breast and other human tumors supports the paradigm that for any chromosomal locus, allelic loss associated with a mutation in the remaining tumor allele signifies an involved tumor suppressor gene. Given this paradigm, there are nearly a dozen putative breast tumor suppressor genes under active investigation, with most investigators now focusing on various chromosome 17 loci. Among the known proto-oncogenes found activated in breast cancer, amplification of c-erbB-2 at 17q21 is the most widely studied and clinically significant gain-of-function event uncovered to date, occurring in about 20% of all primary breast tumors. The involvement of this overexpressed membrane receptor has engendered interest in related tyrosine kinase receptors, such as EGFR, IR, and IGF-I-R, as well as their respective ligands, which may be overexpressed in a greater fraction of tumors, contributing to the autocrine and paracrine regulation of breast cancer growth and metastasis. New attention is being given to the potentially oncogenic function of structurally altered nuclear transactivating steroid hormone receptors, such as ER, whose overexpression has long been used to determine endocrine therapy and prognosis for individual breast cancer patients. While c-myc was one of the first known proto-oncogenes to be found amplified and overexpressed in human breast cancers, the actual incidence and clinical significance of its activation remain disputed and in need of further study. Lastly, we can expect greater clarification about the importance of various 11q13 genes found coamplified in nearly 20% of primary breast cancers, and pursuit into the intriguing possibility that a cyclin-encoding gene represents the overexpressed locus of real interest in this amplicon. Virtually all of these important genetic abnormalities identified thus far are associated with but not restricted to human breast cancers. The absence of identifiable molecular defects relating to the tissue specificity of this malignancy must be considered a substantial gap in our basic understanding of breast carcinogenesis.(ABSTRACT TRUNCATED AT 400 WORDS)

c-erbB-2 positive breast tumours behave more aggressively in the first years after diagnosis

In a retrospective study the expression of the c-erbB-2 oncogene was determined immunohistochemically in 276 breast cancer samples from 253 patients with the antibody 21N. The follow-up period was between 7 and 12 years. This study showed a trend for an inverse relationship between c-erbB-2 positive tumours and estrogen receptors (ER). A correlation was assessed between c-erbB-2 positive tumours and histological grade, liver metastases as first site of metastases, disease free survival time (DFS) in the second and third year after diagnosis and overall survival time (OST) in the third and fourth year after diagnosis. A trend was seen between c-erbB-2 positive tumours and tumour size. No correlation was found between c-erbB-2 positive tumours and age at diagnosis. The method of operation and lymph node involvement. From this study we conclude that there is a significant difference in prognosis the first years after diagnosis, but this difference seems to vanish in a longer follow-up period of 12 years. This provides us with an explanation for the discrepancies in literature concerning c-erbB-2 expression and prognosis in breast cancer. Some investigators did not show differences in prognosis between positive and negative cases after a long follow-up period whereas investigations with a short term follow-up period up to 2-3 years have indeed established a more aggressive behaviour of c-erbB-2 overexpressionary tumours.

Prognostic value of c-erbB-2 expression in uterine cervical carcinoma

AIMS

To study the pattern of expression and prognostic importance of c-erbB-2 protein in cervical carcinoma.

METHODS

Sixty two cases of stage IB/IIA cervical carcinoma, representing the three main tumour types, were investigated immunohistochemically for the presence of c-erbB-2 protein expression, using a monoclonal antibody (CB11) to its internal domain. Follow up of at least five years' duration was available in all cases.

RESULTS

Definite membrane staining was seen in 38.7% of cases. There was a strong correlation with poor survival (p less than 0.0001) particularly. For those with adenocarcinomas, this was the case when nodal metastases were present. In contrast, for squamous carcinomas and adenosquamous carcinomas, the association with a poor prognosis was most apparent in those patients without lymph node metastases.

CONCLUSIONS

These findings raise the possibility that immunostaining for c-erbB-2 protein could be used as a prognostic marker and may help identify those patients for whom early adjuvant treatment might be beneficial.

Prognostic factors in human primary breast cancer: comparison of c-myc and HER2/neu amplification

Amplification of oncogenes in primary tumours may have prognostic and/or therapeutic significance for patients with breast cancer. We have studied HER2/neu and c-myc amplification together with steroid receptors in human primary breast tumours and related the outcome with (relapse-free) survival. A strong inverse correlation was found between HER2/neu amplification and the presence of oestrogen and progesterone receptors. Actuarial 5-years survival showed that breast cancer patients with c-myc amplification in their primary tumours experience a shorter relapse-free survival, especially in node-negative and in receptor-positive tumours, whereas HER2/neu amplification may be of prognostic value for overall survival in receptor-negative tumours. Overall, in our hands, c-myc amplification appeared to be a more potent prognosticator than HER2/neu amplification in human primary breast cancer.

Identification and interpretation of epidermal growth factor and c-erbB-2 overexpression

Overexpression of normal cellular genes may be one mechanism by which malignant cells can acquire a selective growth advantage. The epidermal growth factor receptor and the c-erbB-2 protein are members of the erbB family and are good examples of genes that appear to act through this mechanism. Molecular and biochemical analyses of these two proteins also illustrate how studies of growth factors, growth factor receptors and oncogenic retroviruses may lead to new approaches to diagnosis and treatment. In particular, overexpression of these growth factor receptors has identified clinical subgroups that may respond differently to chemotherapy and provides the opportunity for antibody targeted therapy. Overexpression of these proteins can be identified using immunocytochemistry on both histological sections and fine-needle aspirates, thus enabling these parameters to be assessed preoperatively and to be monitored during therapy.

Prevalence of amplification of the oncogenes c-myc, HER2/neu, and int-2 in one thousand human breast tumours: Correlation with steroid receptors

The frequency of oncogene amplification described in the literature shows a large fluctuation, which could be attributed to the study of relatively small series of tumours, to selection of subgroups of patients, or, especially in retrospective studies, to selection of tumour material from the tumour-bank. To address this question, we have studied amplification of c-myc, HER2/neu and int-2/bcl-1 genes in a series of 1052 collected human breast tumours. The retrospective and prospective subgroups in this collected series of tumours were of equal size. c-myc was amplified in 17.1%, HER2/neu in 18.7% and int-2/bcl-1 in 14.1%, of all breast cancer specimens studied. In the retrospective subgroup the prevalence of amplification was 18.1% for c-myc; 22.6% for HER2/neu and 11.6% for int-2/bcl-1, whereas in the prospective subgroup an incidence of amplification of 16.1%, 15.1% and 16.3% for c-myc, HER2/neu and int-2/bcl-1, respectively was observed. HER2/neu amplification was negatively correlated with oestrogen receptor (ER) and progesterone receptor (PR) status (P less than 0.0001; for both), c-myc amplification was more prevalent in the PR-negative subpopulation (P less than 0.05) and int-2/bcl-1 amplification was positively correlated with ER status (P less than 0.001).

Indicators of increased breast cancer risk in humans

Specific atypical histological patterns of epithelial hyperplasia (AH) indicate a medically relevant risk of breast cancer development in 5-10% of women with otherwise benign biopsies. This risk is about four times that of similar women, i.e., of the same age and at risk for the same length of time. These relative risks are not stable with time and fall 10-15 years after detection. Absolute risk for invasive breast cancer after AH is about 10% in 10-15 years after biopsy and is most certain for perimenopausal women. Proliferative disease without atypia predicts only a slight elevation of risk with a relative risk (RR) of 1.5 to 2 times that of the general population. There is such a strong interaction between family history and AH that it is relevant to consider women with atypical hyperplasia who have a positive family history (FH) of breast cancer separately from those who do not. The absolute risk of breast cancer development in women with AH without a FH was 8% in 10 years (RR about 4), whereas those with a positive family history experienced a risk of about 20% at 15 years (RR of about 10). This interaction of AH and FH has also been observed in other recent studies. Low replacement doses of conjugated estrogen after menopause do not further elevate risk beyond that identified by histology.(ABSTRACT TRUNCATED AT 250 WORDS)