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- Gunnarsson, Cecilia, 1970-, et al.
(författare)
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Amplification of HSD17B1 and ERBB2 in primary breast cancer
- 2003
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Ingår i: Oncogene. - : Springer Science and Business Media LLC. - 0950-9232 .- 1476-5594. ; 22:1, s. 34-40
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Tidskriftsartikel (refereegranskat)abstract
- Estrogens play a crucial role in the development of breast cancer. Estradiol can be produced in the breast tissue in situ, and one of the enzymes involved in this process is 17β-hydroxysteriod dehydrogenase (17β-HSD) type 1 that catalyzes the interconversion of estrone (E1) to the biologically more potent estradiol (E2). The gene coding for 17β-HSD type 1 (HSD17B1) is located at 17q12-21, close to the more studied ERBB2 and BRCA1. The aim of this study was to investigate if HSD17B1 shows an altered gene copy number in breast cancer. We used real-time PCR and examined 221 postmenopausal breast tumors for amplification of HSD17B1 and ERBB2. In all, 32 tumors (14.5%) showed amplification of HSD17B1 and 21% were amplified for ERBB2. Amplification of the two genes was correlated (P = 0.00078) and in 14 tumors (44%) with amplification of HSD17B1, ERBB2 was co amplified. The patients with amplification in at least one of the genes had a significantly worse outcome than patients without (P = 0.0059). For estrogen receptor (ER)-positive patients who received adjuvant tamoxifen, amplification of HSD17B1 was related to decreased breast cancer survival (P = 0.017), whereas amplification of ERRB2 was not. Amplification of HSD17B1 might be an indicator of adverse prognosis among ER-positive patients, and possibly a mechanism for decreased benefit from tamoxifen treatment.
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| 2. |
- Stenmark Askmalm, Marie, et al.
(författare)
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Mutation and accumulation of p53 related to results of adjuvant therapy of postmenopausal breast cancer patients
- 2004
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Ingår i: Acta Oncologica. - : Informa UK Limited. - 0284-186X .- 1651-226X. ; 43:3, s. 235-244
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Tidskriftsartikel (refereegranskat)abstract
- p53 protein accumulation and gene mutation have been implicated in resistance to cytotoxic treatment. This study was performed to further assess the predictive value of p53 in breast cancer. Postmenopausal patients were randomized to adjuvant chemotherapy with cyclophosphamide, metothrexate, or 5-fluorouracil (CMF) vs. Postoperative radiotherapy. The patients were also randomized to adjuvant tamoxifen vs. No endocrine treatment. Immunohistochemistry (IHC) and single-strand conformation polymorphism (SSCP), followed by direct sequencing, was performed. The p53 altered group, regarded as positive for p53 gene mutation and/or p53 protein accumulation, tended to benefit more from CMF than from radiotherapy as compared with others regarding distant recurrences. In the group lacking p53 alteration there was a significantly decreased local recurrence rate in the radiotherapy group as compared with the CMF group (RR = 0.24, 95% CI = 0.083-0.62), whereas no benefit from radiotherapy was found for patients snowing p53 alterations. Tamoxifen significantly decreased the rate of distant recurrence for estrogen receptor-positive patients with no apparent difference in relation to p53 alteration. It is suggested that p53 alteration indicates benefit from CMF compared with radiotherapy regarding distant recurrence-free survival and the best local control with radiotherapy is achieved in the absence of p53 alteration. Finally, altered p53 status is probably not a marker of resistance to tamoxifen.
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