| Abstract|| |
Context: The c-erbB-2 proto-oncogene is a member of the epidermal growth factor receptor family and has been associated with a more aggressive breast tumor biology and resistance to some types of treatments. Aims: The aim is to investigate the correlation among bcl-2 and c-erbB-2 and the micronucleus (MN) formation in patients with early breast cancer (BC). Materials and Methods: This study was conducted between May 2010 and December 2011. We analyzed the MN frequencies in 15 patients with invasive breast carcinoma (IBC), 13 patients with intraductal proliferative lesion (IDPL) and 12 benign breast lesion (BBL). The sample consisted of 40 formalin-fixed, paraffin-embedded blocks of benign and malignant breast tissue. The specimens were evaluated for bcl-2 or c-erbB-2 immunoreactivity was semi-quantitatively evaluated in at least 1000 cells examined under the microscope at 40Χ magnification and recorded as the percentage of c-erbB-2 and bcl-2 positive tumor cells over the total number of cells examined in the same area. The percentage scores were subsequently categorized using the 5% cut-off point for positive staining. Results: The MN was significantly increased in IBC and in IDPL patients compared to BBL patients (3.82 ± 0.17 and 2.37 ± 0.52, respectively, vs. 1.61 ± 0.40, P < 0.001). On other hand, the MN frequencies in IBC patients were higher than those in IDPL patients (3.82 ± 0.17 vs. 2.37 ± 0.52, P < 0.01). c-erbB-2, had the highest record in IBC (60%), and the score was not observed in both IDPL and BBL: bcl-2 immunostaining was also assessed, the lowest recorded score was in IBC (46.66%) and the highest in both BBL and IDPL (100%). Furthermore, there was a significantly difference in the mean MN frequency between c-erbB-2 positive IBC patients (4.06 ± 0.48) and c-erbB-2 negative IBC patients (3.44 ± 0.39) (P < 0.05). Conclusions: Our results suggest that increased chromosome / DNA instabilities may be associated with the pathogenesis of early BC.
Keywords: Breast cancer, breast precancerous lesions, micronucleus test, c-erb2 gene, bcl-2 gene
|How to cite this article:|
Kabalar ME, Karaman A, Aylu B, Özmen SA, Erdem I. Genetic alterations in benign, preneoplastic and malignant breast lesions. Indian J Pathol Microbiol 2012;55:319-25
|How to cite this URL:|
Kabalar ME, Karaman A, Aylu B, Özmen SA, Erdem I. Genetic alterations in benign, preneoplastic and malignant breast lesions. Indian J Pathol Microbiol [serial online] 2012 [cited 2020 Jul 16];55:319-25. Available from: http://www.ijpmonline.org/text.asp?2012/55/3/319/101737
| Introduction|| |
Breast cancer (BC), like most other forms of malignancy, is mainly a multifactorial disease, occurring as a result of the combined effects of environmental and heritable factors. In only 5 -10% of the patients is the disease transmitted in a Mendelian fashion.  Family history is considered to be an important risk factor for the development of carcinoma of the breast.  It has been suggested that much of the increase in familial recurrence risk may be attributable to heritable factors. ,
c-erbB-2 overexpression or amplification is frequently, although not invariably, associated with a poor clinical outcome. ,, In recent times, c-erbB-2 gene amplification has been reported to correlate with the expression of the apoptosis-suppressing genes bcl-2 and bcl-xL in breast cancer.  Downregulation of bcl-2 and bcl-xL with antisense oligonucleotides increased the proapoptotic activity of trastuzumab.  This led to the hypothesis that combined targeting of c-erbB-2 and bcl-2 or bcl-xL mightrepresent a more effective breast cancer therapy compared to targeting only the individual factors. Only little is known about the relationship between c-erbB-2 and bcl-2 family members. Members of the bcl-2 family act as master regulators of mitochondrial homeostasis and apoptosis.  Transfection of c-erbB-2 into MCF-7 breast cancer cells has been shown to upregulate the expression of the bcl-2 family members. , At present, the prognostic value of overexpression or amplification of c-erbB-2 in breast cancer is controversial. , The expression of the antiapoptotic protein bcl-2 varies in breast cancer and seems to be associated with a favorable phenotype. 
In breast cancer, the clinical outcome is affected by a number of established prognostic factors, including age, tumor grade, estrogen receptor (ER) and progesterone receptor (PR) status. , In breast cancer specimens, bcl-2 expression is associated with markers of better differentiation, like lower grade lesions, ER positivity, and a low proliferation status.  Previous studies have shown the prognostic and predictive value of c-erbB-2 over-expression in node-positive breast cancer , and in metastatic disease. ,
Some studies have revealed reduced DNA repair capacity in peripheral blood mononuclear cells from BC patients, as evaluated by the chromosome aberration assay, ,, as well as by the micronucleus (MN) test. ,, The MN test in peripheral blood lymphocytes has been widely used as a biomarker of chromosomal damage both in vivo and in vitro., The frequency of MN is increased in untreated cancer patients and in subjects affected by cancer-prone congenital diseases, for example, Bloom syndrome or ataxia telengiectasia. , Furthermore, an association between MN and cancer has been reported.  The cause of this association may be structural chromosomal aberrations and aneuploidy. ,
We investigated the correlation among bcl-2 and c-erbB-2 and MN formation in patients with early breast cancer (BC).
| Materials and Methods|| |
This study was conducted between May 2010 and December 2011. Forty patients with diagnosed breast lesions of diagnosed were studied. The specimens were separated for each level and placed in 10% formalin solution.
The pathological specimens were reviewed independently by two pathologists. The pathologists were blinded to the subject's clinical history, and the results of the immunohistochemistry staining assay. The pathological reading was determined for each biopsy slide with an overall pathological diagnosis determined for each subject.
Permission was obtained from the Local Ethical Committee to collect breast tissues and all the patients gave informed consent to the research. The specimens (n = 40) were washed in phosphate-buffered saline (PBS) within five minutes and examined under a binocular dissecting microscope. Breast tissues were selected and fixed in freshly prepared 4% paraformaldehyde (4 g in 100 ml of 100 mmol / l PBS, pH 7.2) at 4°C for 24 hours. The breast masses were then embedded in paraffin wax with the breast tissues as close to the surface of the block as possible. Sections (5 μm) were cut and mounted on poly-L-lysine coated slides. Every tenth slide was stained with haematoxylin and eosin and examined in order to identify the breast tissue.
The slides containing breast tissue, were air-dried and heated for 20 minutes at 60°C before dewaxing, with xylene and rehydration. Two different mouse monoclonal antibodies were used in this study. Two negative controls were used, the primary antibody was replaced either with Tris-buffered saline (TBS), containing 0.1% bovine serum albumin (BSA), or by mouse immunoglobulin G (IgG) at the same concentration as the primary antibody. The positive controls were tissues known to express the antigen being studied. In order to maximize visualization of the gene product, each antibody was tested in a series of dilutions, with and without antigen retrieval (unmasking of epitopes after paraformaldehyde fixation and paraffin embedding) and in the presence and absence of enhancement steps. Antigen retrieval conditions (pH of the buffer, heating intensity and time) were altered in order to ascertain optimal antigen detection with minimal background staining for each antibody used.  For bcl-2, and c-erbB-2, optimization of immunohistochemical staining was achieved by pressure cooking the sections in 10 mmol / l citrate buffer (pH 6.0), for four minutes, at low pressure, in an aluminium pressure cooker. After dilution of the antibody in TBS containing 0.1% BSA, sections were incubated at room temperature for 60 minutes. The second antibody, a rabbit anti-mouse Ig antiserum (Dako Ltd., Bucks, UK) was then applied at 1 : 50 dilution for 30 minutes, at room temperature. This was followed by treatment with alkaline phosphatase anti-alkaline phosphatase complex (APAAP) (1 : 50 dilution for 30 minutes at room temperature, Dako Ltd.). To enhance the intensity of the APAAP labelling reaction, the second and third incubation steps were repeated (each step for 30 minutes). For development of alkaline phosphatase, the new fuchsin method was employed, with a substrate solution containing Tris-HCl, pH 8.8 (20 minutes, room temperature); 0.2 mmol / l levamisole was used to inhibit endogenous alkaline phosphatase. Finally, the sections were counterstained with haematoxylin for 20 seconds and mounted on Aquamount (BDH Laboratories, Poole, UK).
Cell membrane reactivity for the c-erbB-2 oncoprotein was evaluated following a similar approach and the mean value was used to score each case. Tumors expressing c-erbB-2 in > 30% of the cancer cells were considered as positive. bcl-2 immunoreactivity was categorized in to four groups: Score 0: negative (no staining). Score 1: + weak positive (staining in 5 - 20% of the neoplastic cells). Score 2: ++ moderate positive (staining in 20 - 50% of the neoplastic cells). Score 3: +++ strong positive (staining in more than 50% of the neoplastic cells). In addition, for estrogen receptor (ER) and progesterone receptor (PR) expression the percentage of cancer cells showing a nuclear reactivity was recorded after inspection of all optical fields at 200X and the mean value was used to score each case. Tumors with expression of > 20% of cancer cells were considered to be positive.
The tumor grade was determined according to the modified Bloom-Richardson score. The grade is obtained by adding up the scores for tubule formation. Final grading scores were as follows (sum of point / final grade: 3 - 5 / I, 6 - 7 / II, and 8 - 9 / III). In addition, endolymphatic emboli, and status of lymph node metastasis was shown in patients with IBC.
We performed MN analysis in 15 females (mean age: 55.47 ± 13.83 years; age range: 38 - 88) patients with IBC: in 13 females (mean age: 35.62 ± 10.03 years; age range: 20 - 54) patients with IDPL: and in 12 females (mean age: 27.58 ± 6.67 years; age range: 15 - 42) patients with BBL. We selected patients from non-smoking and nonalcoholic subjects. None of the subjects had a history of viral infection, bacterial infection or any metabolic diseases. The patients had not been treated with anti-neoplastic therapy (chemotherapy or radiotherapy) during the last four months. The patient and control groups were chosen for their similar habits. The hospital Ethical Committee approved the human study. We obtained written in formed consent from each participant. All the patients were analyzed prior to treatment.
For MN analysis, 3 ml of heparinized blood was drawn from each individual. Lymphocyte cultures were established by adding 0.5 ml of whole blood to 5 ml of karyotyping medium (Biological Industries, Beit Haemek, Israel) with 2% phytohaemagglutinin M (PHA; Biological Industries) according to the standard techniques.  The cultures were incubated at 37°C for 72 hours. All the slides were coded and read blind.
Cytochalasin B (6 μg / ml, Sigma, USA) was added, after 44 hours of culture, to the block cytokinesis, allowing for the identification of lymphocytes dividing in the culture. The culture was kept at 37°C for 72 hours. Cells that had undergone the first mitosis were thus recognized as binucleated cells and were selectively screened for the presence of MN. The cells were then treated hypotonically with 0.075 molar KCl for five minutes, at room temperature, and fixed in methanol / acetic acid (3 : 1). The cells were dropped onto slides and stained with 5% Giemsa in a phosphate buffer (pH 6.8), for five minutes. About 1,000 binucleated cells (mean ± SD = 1004.58 ± 5.36, range = 993 - 1027) from each case were examined for MN by an experienced observer. 
The MN rates were analyzed statistically by the Mann-Whitney U-test. To evaluate the correlations between the age, sex, MN rates, c-erbB-2, bcl-2, ER , PR, tumor grade and status of the lymph node the coefficients of Spearman ρ correlation were calculated. A P value less than 0.05 was considered to be significant.
| Results|| |
The associations of IBC, IDPL, and BBL with MN frequencies in groups are shown in [Table 1],[Table 2],[Table 3]. According to these results, MN was significantly increased in IBC patients, and in IDPL patients compared to BBL patients (3.82 ± 0.17 and 2.37 ± 0.52, respectively, vs. 1.61 ± 0.40, P < 0.001). The mean MN frequency of IBC patients was significantly higher than that of IDPL patients (3.82 ± 0.17 vs 2.37 ± 0.52 per metaphase, respectively; P < 0.01). Furthermore, there was a significantly difference in the mean MN frequency between c-erbB-2 positive IBC patients (4.06 ± 0.48) and c-erbB-2 negative IBC patients (3.44 ± 0.39) (P < 0.05). However, there was not difference in the mean MN frequency between bcl-2 positive IBC patients and bcl-2 negative IBC patients (P > 0.05). On the other hand, the MN frequencies did not correlate with the patients' age in the IBC patients (for each, P > 0.05). c-erb2, was with the highest record in IBC (60%) [Figure 1] and the score was not observed in both IDPL and BBL. bcl-2 immunostaining was also assessed, the lowest recorded score was in IBC (46.66 %) [Figure 2], and the highest in both IDPL and BBL (100%). Groups 2 and 3 were not statistically different in bcl-2 and c-erbB-2 status (P > 0.05).
Bcl-2 expression was found to be correlated with ER and PR expression (P < 0.01). However, c-erbB2 over-expression was found to be inversely correlated with bcl-2, ER and PR expression (P < 0.01). In addition, bcl-2(-) tumors were significantly correlated with the histological grade III (P < 0.01). In contrast, c-erbB-2(+) tumors were significantly correlated with the tumor grade III (P < 0.01). Furthermore, In c-erbB-2(+) patients axillary lymph node involvement was higher, and was lesser in bcl-2(+) (P < 0.01). Details are shown in [Table 1].
The micronuclei in the peripheral blood lymphocytes of a patient with IBC are shown in [Figure 3].
|Figure 3: The peripheral blood lymphocytes stained by Giemsa staining of the nuclei. The arrow shows the micronucleus [Giemsa, ×1000].|
Click here to view
|Table 1: Age, age at diagnosis, and immunostaining of bcl-2, c-erbB-2, estrogen receptor (ER), progesterone receptor (PR), modifi ed Bloom- Richardson score (MBRS), angiolymphatic emboli (ALPE), axillary lymph node metastasis (ALNM) rates, and micronucleus (MN) frequencies for the patients with invasive breast carcinoma (IBC)|
Click here to view
|Table 2: Age, age at diagnosis, immunostaining of bcl-2 and c-erbB-2 rates and micronucleus (MN) frequencies for the patients with intraductal proliferative lesion (IDPL)|
Click here to view
|Table 3: Age, age at diagnosis, immunostaining of bcl-2 and c-erbB-2 rates and micronucleus (MN) frequencies for the patients with benign breast lesion (BBL)|
Click here to view
| Discussion|| |
Breast cancer (BC) is a common type of malignancy in females, accounting for approximately 21% of all cancer cases in women worldwide.  Several DNA damage processing and repair pathways constitute a guard system that protects cells against genetic instability and tumorigenesis. Both genetic instability and impaired DNA restitution have been pointed out as factors underlying increased susceptibility to malignancy. , Apart from these rare syndromes, the deficient DNA repair capacity has been proposed to be a predisposing factor in familial BC and in some sporadic BC cases.  Genomic instability has also been described for various hereditary cancers including hereditary BC. ,
To better understand the relationship between the c-erbB-2 and bcl-2 family members, a group studied the extent to which the expression of bcl-2 family members is influenced by conditional the c-erbB-2 expression in the human breast cancer cell line MCF-7, and subsequently, analyzed the prognostic relevance of the identified genes, in patients with breast cancer. Inducible expression of NeuT, an oncogenic version of c-erbB-2, was achieved by the Tet-on system, , and c-erbB-2 expression levels were comparable with the breast tumors scoring 2+ / 3+. Overexpression of cytosol c-erbB-2 was also associated with gene amplification and the cytosol c-erbB-2 levels were significantly different between early, advanced and metastatic breast cancer.  They had reported that overexpression of cytosol c-erbB-2 was observed in recurrent breast cancer more frequently than in primary breast cancer (54 vs. 19%).  Furthermore, in another study, expression of c-erbB-2 was verified in nine (19.1%) of the ductal carcinomas in situ (P = 0.0001). Immunoexpression was not related to the extension of the lesions. There was no expression in the hyperplasias without atypias and adjacent tissues. 
In another study, there was not any advantage to determine c-erbB-2 as a prognostic factor on the overall survival or on relapse-free survival.  Similarly, no statistically significant differences were detected between the c-erbB-2 negative and positive groups, with regard to a five-year disease-free survival (41 and 27%, P = 0.11) and overall survival (60 and 45%, P = 0.33). They found no differences between c-erb2 negative and positive groups regarding disease-free and overall survival.  In this study, c-erb2 had the highest record in BC (63.64%) and the score was not observed in both premalignant lesions or benign lesions.
The bcl-2 is responsible for the inhibition of apoptosis, and is therefore, important for longer cell survival. According to Yanez et al.,  bcl-2 plays an important role in the development of pleomorphic adenoma (PA), as all cases examined were positive for this protein. Bcl-2 staining in this study was positive in about one of the three PA cases, which was in agrement with the other studies, indicating the possible role of bcl-2 as an anti-apoptotic agent. Bcl-2 immunoreactivity was found mainly in the cells surrounding the mesenchmal structures. In this study, bcl-2 immunostaining was also assessed, the lowest recorded score was in BC (45.45 %) and the highest in both premalignant lesion and benign lesion (100%). Groups 2 and 3 were not statistically different for bcl-2 and c-erbB-2 status (P > 0.05).
Previous studies have shown a strong correlation between c-erbB-2 protein over-expression and ER and PR negativity and high tumor grade. ,, In our study, c-erbB-2 positive cases usually had ER(-), PR(-), high tumor grade, and axillary lymph node (+) (P < 0.01). In the previous studies, the expression of bcl-2 in breast cancer was found to be associated with favorable prognostic factors, such as, smaller tumor size, ER positivity, and low nuclear grade. ,, In our study, bcl-2 positive cases usually had ER(+), PR(+), and low tumor grade, and axillary lymph node (-) (P < 0.01). As a result, the bcl-2 and c-erbB-2 status, gives important clues about the biological behavior of tumors. This will provide guidance for the prognosis of the tumor.
There were numerous case-control studies on breast cancer in which the micronucleus test was used to compare the repair capacity between BC cases and controls. , In almost all of them, a proportion of 20 - 50% of the patients could be identified, which showed an increased MN frequency exceeding the ninetieth percentile of the distribution in the controls. Complex inheritance was generally assumed for DNA repair capacity, as indicated by the numerous association studies carried out on cancer cases and the genes involved in DNA repair. The data available for MN frequencies appeared to be compatible with the assumption of continuous variation, when cases were interpreted as a separate group, with an overall slightly reduced repair capacity. In our study, MN was significantly increased in IBC patients, and in IDPL patients compared to BBL patients (3.82 ± 0.17 and 2.37 ± 0.52, respectively, vs. 1.61 ± 0.40, P < 0.001). The mean MN frequency of IBC patients was significantly higher than that of IDPL patients (3.82 ± 0.17 vs. 2.37 ± 0.52 per metaphase, respectively; P < 0.01).
A recently published cohort study linking the frequency of micronuclei in lymphocytes of healthy subjects to the risk of cancer, reported stomach cancer among the sites more specifically associated to micronuclei frequency.  Similar findings have also been reported for pre-neoplastic lesions of the colon  and cervix.  In particular, the higher risks for stomach and intestinal cancers, are in agreement with the literature, which emphasizes the role of chromosome rearrangements in the early stages of these tumors. ,
In our study, there was a difference in mean MN frequency between c-erbB-2 positive IBC patients and c-erbB-2 negative IBC patients (P < 0.05). However, there was no difference in the mean MN frequency between bcl-2 positive IBC patients and bcl-2 negative IBC patients. Our study, which showed increased MN frequencies in the lymphocytes of IBC patients, could support these observations, as the induction of changes in DNA that lead to mutations play a role in carcinogenicity.
These results suggests that genomic instability is present in the early stages of BC. Thus, MN is a promising biomarker for assessing the risk in the process of BC. Therefore, MN may be benefical in the early detection and prevention programs.
| References|| |
|1.||Ford D, Easton DF, Stratton M, Narod S, Goldgar D, Devilee P, et al.Genetic heterogeneity and penetrance analysis of the BRCA1 and BRCA2 genes in breast cancer families. The Breast Cancer Linkage Consortium. Am J Hum Genet 1998;62:676-89. |
|2.||Anderson DE. Familial versus sporadic breast cancer. Cancer 1992;70:1740-6. |
|3.||Kerber RA, O'Brein E. A cohort study of cancer risk in relation to family histories of cancer in the Utah population database. Cancer 2005;103:1906-15. |
|4.||Hemminki K, Granström C. Familial breast cancer: Scope for more susceptibility genes? Breast Cancer Res Treat 2003;82:17-22. |
|5.||Schmidt M, Böhm D, von Törne C, Steiner E, Puhl A, Pilch H, et al. The humoral immune system has akey prognostic impact in node-negative breast cancer. Cancer Res 2008;68:5405-13. |
|6.||Hausherr CK, Schiffer IB, Gebhard S, Baniæ A, Tanner B, Kolbl H, et al. Dephosphorylation of p-ERK1 / 2 in relation to tumor remission after HER-2 and Raf1 blocking therapy in a conditional mouse tumor model. Mol Carcinog 2006;45:302-8. |
|7.||Micke P, Hengstler JG, Ros R, Bittinger F, Metz T, Gebhard S, et al. c-erbB-2 expression in small-cell lung cancer is associated with poor prognosis. Int J Cancer 2001;92:474-9. |
|8.||Siziopikou KP, Khan S. Correlation of HER2 gene amplification with expression of the apoptosis-suppressing genes bcl-2 and bcl-x-L in ductal carcinoma in situ of the breast. Appl Immunohistochem Mol Morphol 2005;13:14-8. |
|9.||Milella M, Trisciuoglio D, Bruno T, Ciuffreda L, Mottolese M,Cianciulli A, et al. Trastuzumab down-regulates Bcl-2 expression and potentiates apoptosis induction by Bcl-2/Bcl-XL bispecific antisense oligonucleotides in HER-2 gene-amplified breast cancer cells. Clin Cancer Res 2004;10:7747-56. |
|10.||Cory S, Adams JM. The Bcl2 family: Regulators of the cellular life-or-death switch. Nat Rev Cancer 2002;2:647-56. |
|11.||Gee JM, Robertson JF,Ellis IO,Willsher P,McClelland RA,Hoyle HB, et al. Immunocytochemical localization of bcl-2 protein in human breast cancers and its relationship to a series of prognostic markers and response to endocrine therapy. Int J Cancer 1994;59:619-28. |
|12.||Leek RD, Kaklamanis L, Pezzella F, Gatter KC, Harris AL. bcl-2 in normal human breast and carcinoma, association with oestrogen receptor-positive, epidermal growth factor receptor-negative tumors and in situ cancer. Br J Cancer 1994;69:135-9. |
|13.||Seshadri R, Firgaira FA, Horsfall DJ, McCaul K, Setlur V, Kitchen P. Clinical significance of HER-2/neu oncogene amplification in primary breast cancer. The South Australian Breast Cancer Study Group. J Clin Oncol 1993;11:1936-42. |
|14.||Hartmann LC, Ingle JN, Wold LE, Farr GH Jr, Grill JP, Su JQ, et al. Prognostic value of c-erbB-2 overexpression in axillary lymph node positive breast cancer. Results from a randomized adjuvant treatment protocol. Cancer 1994;74:2956-63. |
|15.||Thomadaki H, Talieri M, Scorilas A. Prognostic value of the apoptosis related genes BCL2 and BCL2L12 in breast cancer. Cancer Lett 2007;247:48-55. |
|16.||Pinto AE, André S, Pereira T, Nóbrega S, Soares J. C-erbB-2 oncoprotein overexpression identifies a subgroup of estrogen receptor positive (ER+) breast cancer patients with poor prognosis. Ann Oncol 2001;12:525-33. |
|17.||Huang HJ, Neven P, Drijkoningen M, Paridaens R, Wildiers H, Van Limbergen E, et al.Association between HER-2 / neu and the progesterone receptor in oestrogen-dependent breast cancer is age-related. Breast Cancer Res Treat 2005;91:81-7. |
|18.||Hamilton A, Piccart M. The contribution of molecular markers to the prediction of response in the treatment of breast cancer: A review of the literature on HER-2, p53 and BCL-2. Ann Oncol 2000;11:647-63. |
|19.||Sjögren S, Inganäs M, Lindgren A, Holmberg L, Bergh J. Prognostic and predictive value of c-erbB-2 overexpression in primary breast cancer, alone and in combination with other prognostic markers. J Clin Oncol 1998;16:462-9. |
|20.||Muss HB, Thor AD, Berry DA, Kute T, Liu ET, Cirrincione CT, et al. c-erbB-2 expression and response to adjuvant therapy in women with node-positive early breast cancer. N Engl J Med 1994;330:1260-6. |
|21.||Cobleigh MA, Vogel CL, Tripathy D, Robert NJ, Scholl S, Fehrenbacher L, et al. Multinational study of the efficacy and safety of humanized anti-HER2 monoclonal antibody in women who have HER2-overexpressing metastatic breast cancer that has progressed after chemotherapy for metastatic disease. J Clin Oncol 1999;17:2639-48. |
|22.||Slamon DJ, Leyland-Jones B, Shak S, Fuchs H, Paton V, Bajamonde A, et al.Use of chemotherapy plus a monoclonal antibody against HER2 for metastatic breast cancer that overexpresses HER2. N Engl J Med 2001;344:783-92. |
|23.||Rigaud O, Guedeney G, Duranton I, Leroy A, Doloy MT, Magdelenat H. Genotoxic effects of radiotherapy and chemotherapy on the circulating lymphocytes of breast cancer patients. II. Alteration of DNA repair and chromosome radiosensitivity. Mutat Res 1990;242:25-35. |
|24.||Helzlsouer KJ, Harris EL, Parshad R, Fogel S, Bigbee WL, Sanford KK. Familial clustering of breast cancer: Possible interaction between DNA repair proficiency and radiation exposure in the development of breast cancer. Int J Cancer 1995;64:14-7. |
|25.||Parshad R, Price FM, Bohr VA, Cowans KH, Zujewski JA, Sanford KK.Deficient DNA repair capacity, a predisposing factor in breast cancer. Br J Cancer 1996;74:1-5. |
|26.||Scott D, Barber JB, Levine EL, Burrill W, Roberts SA. Radiation-induced micronucleus induction in lymphocytes identifies a high frequency of radiosensitive cases among breast cancer patients: a test for predisposition? Br J Cancer 1998;77:614-20. |
|27.||Scott D, Barber JB, Spreadborough AR, Burrill W, Roberts SA. Increased chromosomal radiosensitivity in breast cancer patients: A comparison of two assays. Int J Radiat Biol 1999;75:1-10. |
|28.||Baeyens A, Thierens H, Claes K, Poppe B, Messiaen L, De Ridder L, et al. Chromosomal radiosensitivity in breast cancer patients with a known or putative genetic predisposition. Br J Cancer 2002;87:1379-85. |
|29.||Fenech M, Holland N, Chang WP, Zeiger E, Bonassi S. The HUman MicroNucleus Project-An international collaborative study on the use of micronucleus technique for measuring DNA damage in humans. Mutat Res 1999;428:271-83. |
|30.||Mateuca R,Lombaert N, Aka PV, Decordier I, Kirsch-Volders M. Chromosomal changes: Induction, detection methods and applicability in human biomonitoring. Biochimie 2006;88:1515-31. |
|31.||Bonassi S, Neri M, Puntoni R. Validation of biomarkers as earlypredictors of disease. Mutat Res 2001;480-1:349-58. |
|32.||Shi SR, Cote RJ, Taylor CR. Antigen retrieval immunohistochemistry: Past, present, and future. J Histochem Cytochem1997;45:327-43. |
|33.||Latt SA, Schreck RR. Sister chromatid exchange analysis. AM J Hum Genet 1980;32:297-313. |
|34.||Fenech M, Morley AA. Measurement of micronuclei in lymphocytes. Mutat Res 1985;147:29-36. |
|35.||Parkin DM, Pisani P, Ferlay J.Estimates of the worldwide incidence of 25 major cancers in 1990. Int J Cancer 1999;80:827-41. |
|36.||Lengauer C, Kinzler KW, Vogelstein B. Genetic instabilities in human cancers. Nature1998;396:643-9. |
|37.||Thompson LH, Schild D. Recombinational DNA repair and human disease. Mutat Res 2002;509:49-78. |
|38.||Rothfuss A, Schütz P, Bochum S, Volm T, Eberhardt E, Kreienberg R, et al. Induced micronucleus frequencies in peripherallymphocytes as a screening test for carriers of a BRCA1 mutation in breast cancer families. Cancer Res 2000;60:390-4. |
|39.||Trost TM, Lausch EU, Fees SA, Schmitt S, Enklaar T, Reutzel D, et al. Premature senescence is a primary fail-safe mechanism of ERBB2-driven tumorigenesis in breast carcinoma cells. Cancer Res 2005;65:840-9. |
|40.||Spangenberg C, Lausch EU, Trost TM, Prawitt D, May A, Keppler R, et al. ERBB2-mediated transcriptional up-regulation of the alpha5beta1 integrin fibronectin receptor promotes tumor cell survival under adverse conditions. Cancer Res 2006;66:3715-25. |
|41.||Imoto S, Ohkura H, Sugano K, Sasaki Y, Ito K, Igarashi T, et al. Determination of cytosol c-erbB-2 protein in breast cancer by sandwich enzyme immunoassay. Jpn J Clin Oncol 1998;28:92-6. |
|42.||Oliveira AB, De Luca LA, Carvalho GT, Arias VE, Carvalho LR, Assunção Mdo C. Immunoexpression of c-erbB-2 in intraductal proliferative lesions of the female breast. Rev Assoc Med Bras 2004;50:324-9. |
|43.||Antunes A, Silva T, Godinho I, Amaral N, Oliveira C. Prognostic value of c-erb-2 immunohistochemistry expression in patients with primary breast cancer and adjuvant treatment with tamoxifen.Acta Med Port 2004;17:271-6. |
|44.||Kuzhan O, Ozet A, Ulutin C, Kurt B, Komurcu S, Ozturk B, et al. Impact of c-erb2 status on survival after high dose chemotherapy in high-risk breast cancer patients. Saudi Med J 2007;28:1374-9. |
|45.||Yáñez M, Roa I, García M, Ibacache G, Villaseca M. Bcl-2 gene protein expression in salivary gland tumors. Rev Med Chil 1999;127:139-42. |
|46.||Remvikos Y, Magdelenat H, Dutrillaux B. Genetic evolution of breast cancers. III: Age-dependent variations in the correlations between biological indicators of prognosis. Breast Cancer Res Treat 1995;34:25- 33. |
|47.||Moriki T, Takahashi T, Hiroi M, Yamane T, Hara H. Histological grade in invasive ductal carcinoma of breast correlates with the proliferative activity evaluated by BrdU: An immunohistochemical study including correlations with p53, c-erbB-2 and estrogen receptor status. Pathol Int 1996;46:417-25. |
|48.||Elledge RM, Green S, Howes L, Clark GM, Berardo M, Allred DC, et al. Bcl-2, p53, and response to tamoxifen in estrogen receptor-positive metastatic breast cancer: A Southwest Oncology Group study. J Clin Oncol 1997;15:1916-22. |
|49.||Callagy GM, Pharoah PD, Pinder SE, Hsu FD, Nielsen TO, Ragaz J, et al. Bcl-2 is a prognostic marker in breast cancer independently of the Nottingham Prognostic Index. Clin Cancer Res 2006;12: 2468-75. |
|50.||Tsutsui S, Yasuda K, Suzuki K, Takeuchi H, Nishizaki T, Higashi H, et al. Bcl-2 protein expression is associated with p27 and p53 protein expressions and MIB-1 counts in breast cancer. BMC Cancer 2006;6:187. |
|51.||Scott D, Barber JB, Levine EL, BurrillW,Roberts SA. Radiation-induced micronucleus induction in lymphocytes identifies a high frequency of radiosensitive cases among breast cancer patients: A test for predisposition? BrJCancer 1998;77:614-20. |
|52.||Baeyens A, Van Den Broecke R, Makar A, Thierens H, De Ridder L, Vral A.Chromosomal radiosensitivity in breast cancer patients: Influence of age of onset of the disease. Oncol Rep 2005;13:347-53. |
|53.||BonassiS, Znaor A, Ceppi M, Lando C, Chang WP, Holland N, et al. An increased micronucleus frequency in peripheral blood lymphocytes predicts the risk ofcancer in humans. Carcinogenesis 2007;28:625-31. |
|54.||Cardoso J, Molenaar L, de Menezes RX, van Leerdam M, Rosenberg C, Möslein G, et al. Chromosomal instability in MYH-and APC-mutant adenomatous polyps. Cancer Res 2006;66:2514-9. |
|55.||Olaharski AJ, Sotelo R, Solorza-Luna G, Gonsebatt ME, Guzman P, Mohar A, et al. Tetraploidy and chromosomal instability are early events during cervical carcinogenesis. Carcinogenesis 2006;27:337-43. |
|56.||Norppa H. Cytogenetic biomarkers. IARC Sci Publ 2004;157:179-05. |
|57.||Stewénius Y, Gorunova L, Jonson T, Larsson N, Höglund M, Mandahl N, et al. Structural and numerical chromosome changes in colon cancer develop through telomere-mediated anaphase bridges, not through mitotic multipolarity. Proc Natl Acad Sci USA 2005;102:5541-46. |
Department of Medical Genetics, Erzurum Nenehatun Obstetrics and Gynecology Hospital, 25070 Erzurum
Source of Support: None, Conflict of Interest: None
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3]