_:b7997589 . . _:b7997591 . _:b435821202 "2"^^ . _:b7997575 "13 How ever, it remains controversial whether gene amplification results in overexpression of the TOPOII\u03B1 protein.>>9<<" . _:b7997584 _:b7997588 . _:b7997584 _:b7997589 . _:b7997592 . _:b7997584 "discussion" . _:b7997600 "slides from the resection specimens were evaluated for identification of the steps in cancer progression. ADC and precursor lesions were diagnosed according to the World Health Organization classification,18 as previously reported.19,>>20<< We selected those slides with obvious areas showing BO (100% showed areas with BO not associated with dysplasia), LGD (in >90% of the areas), HGD (in >90%) and ADC (in >90%)." . _:b7997584 . _:b7997584 _:b7997590 . _:b7997584 _:b7997591 . _:b7997562 _:b7997576 . _:b7997598 _:b7997608 . _:b7997562 _:b7997577 . . _:b7997584 _:b7997585 . _:b7997592 "and protein expression for both HER-2 and TOPOII\u03B1, between HER-2 and TOPOII\u03B1 gene amplification and between HER-2 and TOPOII\u03B1 protein expression, confirming the results of previous studies regarding pancreatic and gastric cancers.2,>>4<< Chromosome 17 aneusomy was found to be associated with TOPOII\u03B1 protein overexpression but not with each gene amplification." . _:b7997585 . _:b7997578 . _:b7997562 _:b7997578 . _:b7997584 _:b7997586 . _:b7997562 _:b7997579 . _:b7997584 _:b7997587 . _:b7997562 _:b7997572 . _:b7997584 _:b7997596 . _:b7997595 . _:b7997588 . _:b7997562 _:b7997573 . _:b7997598 _:b7997604 . _:b7997598 _:b7997605 . _:b7997586 . _:b7997562 _:b7997574 . _:b7997584 _:b7997597 . _:b7997598 _:b7997606 . _:b7997562 _:b7997575 . . _:b7997598 _:b7997607 . _:b7997562 _:b7997568 . _:b7997598 _:b7997600 . _:b7997562 _:b7997569 . _:b7997584 _:b7997592 . _:b7997598 _:b7997601 . _:b7997587 . _:b7997562 _:b7997570 . . _:b7997584 _:b7997593 . _:b7997584 _:b7997594 . _:b435821207 . _:b7997562 _:b7997571 . _:b7997598 _:b7997602 . . _:b7997598 _:b7997603 . _:b7997584 _:b7997595 . _:b7997567 . _:b435821194 . _:b7997596 . . _:b435821209 "2"^^ . _:b7997597 . _:b7997580 "results" . _:b435821209 . . _:b435821202 . _:b435821208 "2"^^ . . _:b7997589 "have shown that increased expression of TOPOII\u03B1 in BO is associated with HGD,30 as well as the fact that HER-2 is overexpressed in oesophageal ADC31 and this overexpression may predict early transition from dysplasia to ADC in BO.>>32<< However, to the best of our knowledge the expression of TOPOII\u03B1 and HER-2 has not been previously investigated in BO patients." . . . _:b7997581 . _:b7997598 . _:b435821205 . _:b7997606 . . _:b7997608 . _:b7997599 . . _:b435821210 "2"^^ . _:b7997571 "the fact that amplification of HER-2 has become a valid biomarker to identify patients with breast cancer who respond to HER-2 protein targeting therapy, several recent clinical trials have found that HER-2-overexpressing breast cancers,>>10<< with or without HER-2 amplification,11 are often responsive to anthracycline-based therapies." . _:b7997592 . . _:b7997593 . . _:b7997580 _:b7997581 . _:b7997604 "(Dako). Immunoreactivity was considered positive for TOPOII\u03B1 when at least 10% of dysplastic/neoplastic cells were stained. We applied the same criteria proposed for the quantification of p53 in endometrial and breast carcinomas.23,>>24<< All samples were scored quantitatively and qualitatively at \u00D740 high-power fields (HPF) in every section (Nikon Eclipse E400, Tokyo, Japan) (Area of high-power field = 0.146 mm2)." . _:b7997594 . _:b7997580 _:b7997582 . _:b7997569 . _:b7997565 "1\u20135HER-2/neu oncogene encodes for the human epidermal growth factor receptor 2 and it is a well-known marker of poor prognosis in a variety of tumours.>>6<<" . _:b7997580 _:b7997583 . . . _:b7997595 . _:b7997574 "Recent studies have confirmed that patients with breast cancer with TOPOII\u03B1 gene amplification are more sensitive to TOPOII\u03B1-based therapy.>>13<< How ever, it remains controversial whether gene amplification results in overexpression of the TOPOII\u03B1 protein." . _:b7997580 . . _:b7997574 . "10.1111%2Fj.1365-2559.2010.03580.x" . . . _:b7997576 "13 How ever, it remains controversial whether gene amplification results in overexpression of the TOPOII\u03B1 protein.9,>>14<<" . _:b7997604 . _:b7997597 "These potential markers might also contribute to deciding alternative therapeutic approaches, as suggested by some preliminary data.>>36<<" . . _:b7997605 . . _:b7997596 "clinical studies have shown that TOPOII\u03B1 gene amplification is a more specific predictor than TOPOII\u03B1 expression assessed by immunohistochemistry and HER-2 gene amplification for clinical response to TOPOII\u03B1 inhibitors in breast cancer.>>35<< For this reason, FISH testing for TOPOII\u03B1 status in addition to HER-2 evaluation may be useful in the characterization of Barrett\u2019s pathology and progression to dysplasia." . _:b7997606 . "PMC0" . _:b7997607 . . _:b7997598 . _:b7997584 . _:b7997600 . _:b435821193 . _:b7997601 . _:b7997601 . _:b7997568 "In vitro studies have shown a correlation between the expression level of TOPOII\u03B1 in cancer cells and the sensitivity of those cells to topoisomerase inhibitors.8,>>9<<" . . . . _:b7997602 . . _:b7997593 . . _:b7997582 "of dysplasia and ADC showed co-amplification of TOPOII\u03B1 and HER-2/neu genes (>50%). HER-2/neu gene amplification was higher then TOPOII\u03B1 (Figure 1D) because of the clustering (>10 signals) (Figure 2B), as also reported in previously.3,>>4<<,28 No deletions were seen in any of the 44 patients analysed. There was no significant association between protein/gene overexpression/amplification and age or gender (data not shown)." . _:b7997565 . _:b7997603 . _:b7997577 . _:b7997567 "In vitro studies have shown a correlation between the expression level of TOPOII\u03B1 in cancer cells and the sensitivity of those cells to topoisomerase inhibitors.>>8<<" . _:b7997605 . _:b7997604 . _:b7997562 . _:b7997606 "Counterstaining of nuclei was performed using 4,6-diamidino-2-phenylindole. A special amplification pattern as Her-2/neu\u2018signal clusters\u2019, usually with >10 confluent signals, was observed, as previously described.25,>>26<< Although gene amplification as \u2018homogeneously stained regions\u2019 was clearly evident, this pattern did not allow precise signal enumeration." . . _:b7997587 . _:b435821195 . _:b7997608 . . _:b7997581 "of dysplasia and ADC showed co-amplification of TOPOII\u03B1 and HER-2/neu genes (>50%). HER-2/neu gene amplification was higher then TOPOII\u03B1 (Figure 1D) because of the clustering (>10 signals) (Figure 2B), as also reported in previously.>>3<<,4,28 No deletions were seen in any of the 44 patients analysed. There was no significant association between protein/gene overexpression/amplification and age or gender (data not shown)." . _:b435821198 . _:b7997570 "others have demonstrated that TOPOII\u03B1 amplification, identified by fluorescence in situ hybridization (FISH), may occur with or without HER-2 duplication and is often associated with TOPOII\u03B1 expression evaluated by immunohistochemistry.>>1<<" . _:b7997593 "No deletions for TOPOII\u03B1 and/or HER-2/neu were seen in any of our patients, whereas monoallelic deletions were found in other pathological conditions, i.e. breast cancer.>>3<<" . _:b7997572 "become a valid biomarker to identify patients with breast cancer who respond to HER-2 protein targeting therapy, several recent clinical trials have found that HER-2-overexpressing breast cancers,10 with or without HER-2 amplification,>>11<< are often responsive to anthracycline-based therapies. In fact, it has been proposed that HER-2 amplification in these tumours may be a marker of TOPOII\u03B1 amplification." . _:b435821206 . _:b7997586 "the concept that in breast cancer the association between HER-2 amplification and response to anthracycline-based chemotherapy is not a direct effect of HER-2 overexpression but the result of co-amplification of the TOPOII\u03B1 gene.>>29<< Some studies have shown that increased expression of TOPOII\u03B1 in BO is associated with HGD,30 as well as the fact that HER-2 is overexpressed in oesophageal ADC31 and this overexpression may predict early transition from dysplasia to ADC" . _:b7997564 . _:b435821191 . _:b435821190 . _:b435821191 . _:b7997563 "HER-2/neu and topoisomerase II\u03B1 (TOPOII\u03B1) genes are both located on chromosome 17q, and they can be co-amplified in cancer.>>1<< Amplification of both genes has been reported in breast, prostatic, gastric, colorectal and pancreatic carcinomas." . . _:b7997595 "33 However, acid reflux also causes inflammatory responses known to contribute to carcinogenesis.>>34<<" . _:b7997586 . . _:b7997563 . _:b7997603 . _:b7997607 "Following these criteria>>23<<,27 the cell population of each HPF was classified as displaying disomy, polysomy or an amplification of the Her-2/neu gene." . _:b7997568 . _:b435821192 . . _:b7997599 . _:b7997590 . _:b435821197 . . . _:b7997591 "and protein expression for both HER-2 and TOPOII\u03B1, between HER-2 and TOPOII\u03B1 gene amplification and between HER-2 and TOPOII\u03B1 protein expression, confirming the results of previous studies regarding pancreatic and gastric cancers.>>2<<,4 Chromosome 17 aneusomy was found to be associated with TOPOII\u03B1 protein overexpression but not with each gene amplification." . _:b435821196 . . _:b7997598 "patients and methods" . . _:b7997607 . _:b435821199 . _:b435821198 . _:b7997608 "Following these criteria23,>>27<< the cell population of each HPF was classified as displaying disomy, polysomy or an amplification of the Her-2/neu gene." . _:b7997575 . _:b435821203 . _:b7997603 "(Dako). Immunoreactivity was considered positive for TOPOII\u03B1 when at least 10% of dysplastic/neoplastic cells were stained. We applied the same criteria proposed for the quantification of p53 in endometrial and breast carcinomas.>>23<<,24 All samples were scored quantitatively and qualitatively at \u00D740 high-power fields (HPF) in every section (Nikon Eclipse E400, Tokyo, Japan) (Area of high-power field = 0.146 mm2)." . _:b435821193 . . _:b7997578 "Adenocarcinoma (ADC) of the oesophagus is currently the cancer with the fastest increasing incidence in the USA, and has replaced squamous cell carcinoma as the most common oesophageal malignancy.>>16<<,17 In fact, an increase in relative and absolute numbers of ADCs of the lower third of the oesophagus has been observed in many Western countries." . _:b7997577 "13 How ever, it remains controversial whether gene amplification results in overexpression of the TOPOII\u03B1 protein.9,14,>>15<<" . _:b435821192 . _:b7997573 "In fact, it has been proposed that HER-2 amplification in these tumours may be a marker of TOPOII\u03B1 amplification.>>12<<" . . _:b7997583 . _:b435821195 . _:b435821200 . _:b7997569 "Some authors have suggested a concordance of HER-2 and TOPOII\u03B1 gene amplification in breast cancer,>>3<< while others have demonstrated that TOPOII\u03B1 amplification, identified by fluorescence in situ hybridization (FISH), may occur with or without HER-2 duplication and is often associated with TOPOII\u03B1 expression evaluated by" . _:b435821194 . . _:b7997576 . _:b435821205 . _:b7997579 . _:b7997564 . . _:b435821204 . _:b435821190 . . _:b7997564 . _:b435821207 . _:b435821199 . _:b435821210 . . _:b7997565 . . . . _:b435821206 . . _:b7997566 . _:b435821201 . . _:b7997567 . _:b435821200 . _:b7997585 . _:b435821203 . _:b435821201 . _:b7997564 "and topoisomerase II\u03B1 (TOPOII\u03B1) genes are both located on chromosome 17q, and they can be co-amplified in cancer.1 Amplification of both genes has been reported in breast, prostatic, gastric, colorectal and pancreatic carcinomas.>>1<<\u20135HER-2/neu oncogene encodes for the human epidermal growth factor receptor 2 and it is a well-known marker of poor prognosis in a variety of tumours." . _:b435821202 . _:b7997571 . . _:b7997601 "expression was assessed by two investigators (E.R., V.V.), following the scoring system recommended by the manufacturer\u2019s instructions and the Food and Drug Administration (FDA) guidelines, according to the Hercep Test\u00AE criteria.>>21<<,22 Immunoreactivity was scored as follows:" . _:b7997562 . _:b435821191 "2"^^ . _:b7997585 "Topoisomerases are nuclear enzymes that regulate cellular processes such as replication and transcription; in addition, these enzymes represent a major molecular target for drugs of the anthracycline class or chemotherapeutic agents.>>9<< Clinical and in vitro evidence supports the concept that in breast cancer the association between HER-2 amplification and response to anthracycline-based chemotherapy is not a direct effect of HER-2 overexpression but the result of" . . _:b7997583 "of dysplasia and ADC showed co-amplification of TOPOII\u03B1 and HER-2/neu genes (>50%). HER-2/neu gene amplification was higher then TOPOII\u03B1 (Figure 1D) because of the clustering (>10 signals) (Figure 2B), as also reported in previously.3,4,>>28<< No deletions were seen in any of the 44 patients analysed. There was no significant association between protein/gene overexpression/amplification and age or gender (data not shown)." . _:b7997596 . . _:b7997563 . _:b435821190 "2"^^ . _:b7997600 . _:b7997572 . . . . _:b7997573 . _:b7997564 . _:b7997574 . _:b7997597 . _:b435821209 . _:b435821208 . _:b7997575 . . _:b435821209 . _:b435821210 . _:b435821208 . . _:b7997568 . _:b435821197 . _:b7997564 . _:b7997602 "expression was assessed by two investigators (E.R., V.V.), following the scoring system recommended by the manufacturer\u2019s instructions and the Food and Drug Administration (FDA) guidelines, according to the Hercep Test\u00AE criteria.21,>>22<< Immunoreactivity was scored as follows:" . _:b435821197 "2"^^ . _:b7997594 . _:b435821208 . _:b7997573 . _:b435821200 . _:b7997569 . _:b435821201 . _:b435821202 . _:b7997590 "In agreement with previous studies on breast carcinomas,>>3<< we confirmed that TOPOII\u03B1 is rarely amplified in the absence of HER-2 amplification, that it is co-amplified with HER-2 in dysplasia (LGD and HGD) and ADC, and that the HER-2 gene copy number, because of clustering, was higher than the" . _:b435821210 . _:b435821196 "2"^^ . _:b435821203 . _:b435821204 . _:b7997582 . _:b7997570 . _:b435821205 . _:b435821206 . _:b435821199 "2"^^ . _:b435821207 . _:b435821192 . _:b7997571 . _:b435821196 . _:b435821193 . . _:b435821194 . _:b435821198 "2"^^ . _:b435821195 . _:b435821196 . . _:b435821197 . _:b7997580 . _:b7997598 _:b7997599 . _:b435821193 "2"^^ . _:b435821198 . _:b435821199 . _:b7997599 "slides from the resection specimens were evaluated for identification of the steps in cancer progression. ADC and precursor lesions were diagnosed according to the World Health Organization classification,18 as previously reported.>>19<<,20 We selected those slides with obvious areas showing BO (100% showed areas with BO not associated with dysplasia), LGD (in >90% of the areas), HGD (in >90%) and ADC (in >90%)." . . _:b7997581 . _:b7997587 "29 Some studies have shown that increased expression of TOPOII\u03B1 in BO is associated with HGD,>>30<< as well as the fact that HER-2 is overexpressed in oesophageal ADC31 and this overexpression may predict early transition from dysplasia to ADC in BO." . _:b435821192 "2"^^ . _:b7997602 . _:b7997582 . _:b7997588 "29 Some studies have shown that increased expression of TOPOII\u03B1 in BO is associated with HGD,30 as well as the fact that HER-2 is overexpressed in oesophageal ADC>>31<< and this overexpression may predict early transition from dysplasia to ADC in BO." . _:b435821190 . _:b435821195 "2"^^ . _:b435821191 . . _:b7997583 . . _:b435821194 "2"^^ . _:b7997576 . _:b7997564 . _:b435821205 "2"^^ . _:b7997577 . _:b7997566 . _:b435821204 "2"^^ . _:b7997578 . _:b7997605 "Counterstaining of nuclei was performed using 4,6-diamidino-2-phenylindole. A special amplification pattern as Her-2/neu\u2018signal clusters\u2019, usually with >10 confluent signals, was observed, as previously described.>>25<<,26 Although gene amplification as \u2018homogeneously stained regions\u2019 was clearly evident, this pattern did not allow precise signal enumeration." . _:b435821204 . _:b7997562 "introduction" . _:b7997566 "1\u20135HER-2/neu oncogene encodes for the human epidermal growth factor receptor 2 and it is a well-known marker of poor prognosis in a variety of tumours.6,>>7<<" . _:b435821207 "2"^^ . _:b7997570 . _:b7997579 . _:b7997562 _:b7997564 . _:b435821206 "2"^^ . _:b7997562 _:b7997565 . _:b7997562 _:b7997566 . _:b7997594 "these factors in cancer development. It is well known that BO is associated with gastrointestinal acid reflux, and it has been suggested that acid reflux could introduce mutations in oesophageal cells due to acid pH-induced DNA damage.>>33<< However, acid reflux also causes inflammatory responses known to contribute to carcinogenesis." . _:b7997588 . _:b7997562 _:b7997567 . _:b7997591 . _:b435821201 "2"^^ . _:b7997572 . _:b7997589 . _:b7997579 "Adenocarcinoma (ADC) of the oesophagus is currently the cancer with the fastest increasing incidence in the USA, and has replaced squamous cell carcinoma as the most common oesophageal malignancy.16,>>17<< In fact, an increase in relative and absolute numbers of ADCs of the lower third of the oesophagus has been observed in many Western countries." . _:b7997562 _:b7997563 . . _:b435821200 "2"^^ . _:b7997590 . . _:b435821203 "2"^^ . .