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Featured researches published by Tomas Seidal.
BMC Cancer | 2013
Ingiridur Skirnisdottir; Kathrine Bjersand; Helena Åkerud; Tomas Seidal
BackgroundClear cell carcinomas are aggressive tumors with a distinct biologic behaviour. In a genome-wide screening for genes involved in chemo-resistance, NAPA was over-expressed in cisplatin-resistant cells. The NAPA (protein) Napsin A was described to promote resistance to cisplatin by degradation of the tumor suppressor p53.MethodsTotally 131 patients were included in this study all in FIGO-stages I-II; 16 were clear cell tumors which were compared with 40 Type I tumors and 75 type II tumors according to the markers Napsin A, p21, p53 and p27 and some clinical features. For detection of the markers tissue microarrays and immunohistochemistry were used.ResultsPositivity for Napsin A was detected in 12 (80%) out of the 15 clear cell tumors available for analysis compared with 3 (4%) out of the Type I and II tumors in one group (p < 0.001). Differences in p21 status, p53 status, and p21 + p53- status were striking when clear cell tumors were compared with Type I, Type II, and Type I and II tumors in one group, respectively. The p21 + p53-status was associated to positive staining of Napsin A (p = 0.0015) and clear cell morphology (p = 0.0003). In two separate multivariate logistic regression analyses with Napsin A as endpoint both clear cell carcinoma with OR = 153 (95% C.I. 21–1107); (p < 001) and p21 + p53- status with OR = 5.36 (95% C.I. 1.6-17.5); (p = 0.005) were independent predictive factors. ROC curves showed that AUC for Napsin A alone was 0.882, for p21 + p53- it was 0.720 and for p21 + p53-Napsin A + AUC was 0.795. Patients with clear cell tumors had lower (p = 0.013) BMI than Type I patients and were younger (p = 0.046) at diagnosis than Type II patients. Clear cell tumors had a higher frequency (p = 0.039) of capsule rupture at surgery than Type I and II tumors.ConclusionsPositivity of Napsin A in an epithelial ovarian tumor might strengthen the morphological diagnosis of clear cell ovarian carcinoma in the process of differential diagnosis between clear cell ovarian tumors and other histological subtypes.
International Journal of Gynecological Cancer | 2011
Ingiridur Skirnisdottir; Bengt Sorbe; Katarina Lindborg; Tomas Seidal
Introduction: The objective of the study was to evaluate the prognostic effect of p53, p27, and C-MYC on clinicopathological features, recurrent disease, and disease-free survival (DFS) of 131 patients with ovarian cancer in International Federation of Gynecology and Obstetrics (FIGO) stages I-II. Methods: The technique of tissue microarray and immunohistochemistry was used for detection of positivity/overexpression of the biological markers p53, p27, and C-MYC. Results: In the complete series, the 5-year and overall survival rates were 68% and 71%, respectively. Positive staining for p53, p27, and C-MYC was detected in 25%, 57%, and 76% of cases, respectively. Positivity of p53, p27, concomitant p53-p27, C-MYC, and C-MYC-p27 status were associated with tumor grade. Positivity of p27 and concomitant p53-p27 were related to serous tumors. In survival analysis, DFS was related to p53, combined p53-p27, and combined p53-C-MYC status. Significant predictive factors for tumor recurrences were the FIGO stage (odds ratio [OR] = 9.8), status of node sampling (OR = 0.2), and p53 status (OR = 3.7) in a logistic regression analysis. In a multivariate Cox regression analysis, FIGO stage (hazard ratio [HR] = 4.3) and p53 status (HR = 3.0) were significant prognostic factors for DFS. In a separate Cox regression analysis, FIGO stage (HR = 2.0) and concomitant p53-p27-C-MYC status (HR = 0.3) were independent prognostic factors for DFS. It was possible to identify a subgroup, constituting 30% of the patients, who had excellent survival with tumors of concomitant p53 negativity, p27 positivity, and C-MYC positivity apart from the clinicopathological factors. Patients in this subgroup were longtime survivors with DFS of 92% at 5 and 9 years. Conclusions: The results of this study strongly suggest that patients with p53-positive tumors (alone/or combined with p27 and/or C-MYC) had significantly worse survival (DFS) compared with patients with p53-negative tumors. Patients with p53-positive tumors continued to have recurrences after the 5-year follow-up and die in disease.
International Journal of Gynecological Cancer | 2011
Ingiridur Skirnisdottir; Tomas Seidal
Introduction: The objective of the study was to evaluate the prognostic effect of p53, PTEN, and concomitant p53 PTEN status on clinicopathologic features, recurrent disease, and disease-free survival (DFS) of 131 patients in FIGO stages I to II with epithelial ovarian cancer. Methods: The technique of tissue microarray and immunohistochemistry was used for the detection of positivity of the biologic markers p53 and PTEN. Results: In the complete series, the 5-year DFS rate was 68%, and the overall survival rate was 71%. Positive staining for p53 and PTEN was detected in 25% and 22% of cases, respectively. Positivity of p53 was associated with tumor grade in the total series but not in the subgroup of serous tumors. In survival analysis, there was worse survival (P = 0.003) in the group of patients with p53-positive tumors compared with the group of patients with p53-negative tumors with DFS of 62% and 82%, respectively. Furthermore, DFS was 15% for the subgroup of patients with concomitant p53-positivity and PTEN-negativity of tumors compared with DFS of 62% for others in 1 group (p53+PTEN+, p53−PTEN+, p53−PTEN−) at 100 months. The difference was highly significant (P = 0.006). FIGO stage (odds ratio = 8.0) and p53 PTEN status (odds ratio = 0.6) were predictive factors for tumor recurrences in a logistic regression and prognostic factors with hazard ratios (HRs) of 4.0 and 0.6, respectively, in a multivariate Cox regression analysis. In a separate Cox regression analysis, FIGO stage (HR = 3.6) and p53 status (HR = 2.0) were prognostic factors for DFS. For serous tumors (n = 51) recurrent disease was associated with FIGO stage (P = 0.013), and p53 loss (P = 0.029) but not with FIGO grade (P = 0.169). Conclusions: p53 status divides ovarian carcinomas into 2 subgroups after prognosis, also in serous tumors. Presence of PTEN in p53-positive tumors seems to protect from bad prognosis and absence of PTEN seems to worsen prognosis in early stages.
International Journal of Oncology | 2016
Ingiridur Skirnisdottir; Tomas Seidal; Helena Åkerud
The aim of this study was to evaluate prognostic effect of the angiogenesis regulators VEGF-R1, VEGF-R2 and VEGF-A for recurrent disease and disease-free survival (DFS), and their relation to the apoptosis regulator p53, in 131 patients with FIGO-stages I–II with epithelial ovarian cancer. For the detection of positivity of the markers the techniques of tissue microarrays and immunohistochemistry (IHC) were used. In tumors the frequency of positive staining for VEGF-R1 was 19%, for VEGF-R2 and VEGF-A, it was 77 and 70%, respectively. Positivity for p53 was detected in 25% of tumors. The total number of recurrences in the complete series was 34 out of 131 (26%) and 5-year disease-free survival (DFS) was 68%. Positive staining for VEGF-A (P=0.030), VEGF-R2 (P=0.011) and p53 (P=0.015) was found more frequently in type II tumors than in type I tumors. Patients with VEGF-R1 negative tumors had worse (P=0.021) DFS compared to patients with VEGF-R1 positive tumors. In two multivariate Cox analyzes with DFS as endpoint, FIGO-stage (HR=3.8), VEGF-R2 status (HR=0.4) and p53 status (HR=2.3), all were significant and independent prognostic factors. When the variables VEGF-R2 and p53 were replaced with the new variable VEGF-R2+p53−/other three combinations in one group, it was found that patients from that subgroup had 86% reduced risk of dying in disease (HR=0.24). Findings above, confirmed relationship between VEGF-R2 and VEGF-A and p53, respectively, with regard to recurrent disease and survival. Some findings from the present study are different from results from previous studies on the regulation of angiogenesis. Despite many trials with anti-angiogenic agents in the front line of ovarian cancer have shown to be positive for progression-free survival, no one has demonstrated an impact on overall survival. Therefore, one of the greatest challenges in ovarian cancer research, is to discover predictive and prognostic biomarkers.
PLOS ONE | 2017
Kathrine Bjersand; Tomas Seidal; Inger Sundström-Poromaa; Helena Åkerud; Ingiridur Skirnisdottir
Objectives To evaluate the prognostic effect of the Heterogeneous nuclear ribonucleoprotein type M (HNRPM) and Solute carrier 1A5 (SLC1A5) in FIGO-stages I-II epithelial ovarian cancer. Methods A retrospective cohort study was designed to investigate the prognostic effect of HNRPM and SLC1A5, and the association with clinical-pathologic characteristics in 131 patients with FIGO-stages I-II epithelial ovarian cancer. Tissue microarrays were constructed and protein levels were assessed by immunohistochemistry (IHC). Results Positive HRNPM status was associated with positive staining for PUMA (P = 0.04), concomitant PUMA and p21 staining (P = 0.005), and VEGF-R2 (P = 0.003). Positive SLC1A5 staining was associated with positive staining of p27 (P = 0.030), PUMA (P = 0.039), concomitant PUMA and p27 staining, and VEGF-R2 (P = 0.039). In non-serous tumors (n = 72), the SLC1A5 positivity was associated with recurrent disease (P = 0.01). In a multivariable logistic regression analysis FIGO-stage (OR = 12.4), tumor grade (OR = 5.1) and SLC1A5 positivity (OR = 0.1) were independent predictive factors for recurrent disease. Disease-free survival (DFS) in women with SLC1A5-positive non-serous tumors was 92% compared with of 66% in patients with SLC1A5-negative non-serous tumors (Log-rank = 15.343; P = 0.008). In Cox analysis with DFS as endpoint, FIGO-stage (HR = 4.5) and SLC1A5 status (HR = 0.3) were prognostic factors. Conclusions As the proteins HRNPM and SLC1A5 are associated with the cell cycle regulators p21 or p27, the apoptosis regulators PTEN and PUMA, and the VEGF-R2 it is concluded that both proteins have role in the pathogenesis of ovarian cancer. In patients with non-serous ovarian cancer SLC1A5 protects from recurrent disease, presumably by means of biological mechanisms that are unrelated to cytotoxic drug sensitivity.
International Journal of Gynecological Cancer | 2015
Ingiridur Skirnisdottir; Tomas Seidal; Helena Åkerud
Objective The objective of this study was to compare immunohistochemical profile for the apoptosis regulators p53, C-MYC, bax, PUMA, and PTEN and the cell cycle regulatory proteins p21 and p27, as well as clinical factors between types I and II tumors. Methods In total, 131 patients in FIGO (International Federation of Gynecology and Obstetrics) stages I-II were divided into 2 groups of patients after type I tumors (n = 79) and type II tumors (n = 52). Differences in the immunohistochemical profile for the cell cycle–related proteins, detected by tissue microarrays and immune-histochemistry, were compared. For statistical tests, the Pearson χ2 test and the logistic regression model were used. All tests were 2-sided, and the level of statistical significance was P ≤ 0.05. Results In multivariate logistic regression analysis with recurrent disease as endpoint, FIGO stage (odds ratio [OR], 4.7), type I/II tumors (OR, 3.8), body mass index (BMI) (OR, 3.5), and p53 status (OR, 4.2) all were found to be independent predictive factors. In 2 different multivariate logistic regression analyses with type I/II tumors as endpoint, both p53+p21− (OR, 2.9) and p27 status (OR, 3.0) were associated with type II tumors. Differently, C-MYC status (OR, 0.4) was associated with type I tumors. Furthermore, age (OR, 1.04), BMI (OR, 0.4), and recurrent disease (OR, 4.3) all were associated to type II tumors. In survival analysis, there was a trend (P = 0.054) toward better disease-free survival for patients with type I tumors. Conclusions Concomitant positivity for p53 and negativity for p21, positivity for p27, and negativity for C-MYC in an epithelial ovarian tumor might strengthen the diagnostic option of type II tumor ovarian carcinoma. Patients with type II tumors were older, had lower BMI, and had more often recurrent disease than patients with type I tumors.
International Journal of Gynecological Cancer | 2001
Ingiridur Skirnisdottir; Bengt Sorbe; Tomas Seidal
International Journal of Gynecological Cancer | 2004
Ingiridur Skirnisdottir; Tomas Seidal; Bengt Sorbe
International Journal of Gynecological Cancer | 2002
Ingiridur Skirnisdottir; Tomas Seidal; E. Gerdin; Bengt Sorbe
International Journal of Oncology | 2005
Ingiridur Skirnisdottir; Tomas Seidal; Mats G. Karlsson; Bengt Sorbe