Abstract P2-08-26: High expression of CYP27A1 in breast cancer is associated with poor tumor pathological features and may differentially predict prognosis depending on menopausal status

Background: Pre-clinical and epidemiological data strongly link high cholesterol with breast cancer progression and poor prognosis. It was recently uncovered that the pathogenicity of cholesterol in breast cancer is directly propagated by 27-hydroxycholesterol (27HC), an oxysterol produced when cholesterol is hydroxylated by cytochrome P450, family 27, subfamily A, polypeptide 1 (CYP27A1) during bile acid synthesis. 27HC promotes breast tumor growth and metastasis via interactions with the estrogen receptor (ER) and liver x receptors respectively. Consequently, pharmaceutical approaches that directly interfere with CYP27A1 activity have been proposed to mitigate the adverse impact of 27HC in breast cancer. However, CYP27A1 expression or deregulation in clinical breast cancer is not well characterised. The aim of this study was to comprehensively describe the impact of tumor-specific expression of CYP27A1 protein on clinical breast cancer pathobiology and prognosis.

Methods: CYP27A1 expression in tumor cells was evaluated by immunohistochemistry in two independent population based cohorts including female patients with primary invasive breast cancer diagnosed between 1991 and 2010 (cohort 1) and between 2002 and 2012 (cohort 2). Staining was evaluable in 645 and 813 cases in cohort 1 and cohort 2, respectively. Associations between CYP27A1 expression with tumor pathological factors and survival were assessed by using logistic and Cox regression models respectively. Multivariable models adjusted for age at diagnosis, nodal status, histological grade, tumor size, ER and BMI.

Results: CYP27A1 was overexpressed in 21% and 28% in cohort 1 and cohort 2 respectively. High CYP27A1 expression was significantly associated with adverse tumor pathological features including negative hormone receptor (ER and PgR) status and histological grade 3 in both cohorts and with larger tumors (>20 mm) in cohort two only (p<0.05, for all comparisons). In multivariable Cox regression analyses, overexpression of CYP27A1 was neither independently prognostic for recurrence-free survival (cohort 2: HR=1.3, 95% CI= 0.88 – 1.9) nor overall survival (cohort 1: HR=1.3, 95% CI= 0.88 – 1.9 and Cohort 2: HR=1.3, 95% CI= 0.81 – 2.0, respectively). Upon stratification for menopausal status using age at diagnosis (< 50 years vs ≥ 50 years) as surrogate, the relationship between CYP27A1 expression and prognosis remained non-significant for older (postmenopausal) patients. Interestingly, among younger (premenopausal) women, elevated CYP27A1 expression was independently prognostic for shorter time to recurrence or death (HR=3.3, 95% CI= 1.5 – 7.4; cohort 2).

Conclusions: Collectively, these results indicate that intratumoral CYP27A1 expression supports the notion that 27HC plays an important pathological role in breast cancer progression but tumor cell-specific CYP27A1 expression is not sufficient to independently predict overall survival in postmenopausal patients. Further sufficiently sized studies are needed to clarify the prognostic significance of CYP27A1 in younger and presumably premenopausal patients and evaluate its role as a treatment predictive factor.

Citation Format: Kimbung S, Stålhammar T, Inasu M, Nodin B, Elebro K, Tryggvadottir H, Jirström K, Rose C, Ingvar C, Jernström H, Borgquist S. High expression of CYP27A1 in breast cancer is associated with poor tumor pathological features and may differentially predict prognosis depending on menopausal status [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-26.

Abstract P4-08-31: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Loughman T, Wang C-JA, Dynoodt P, Fender B, Lopez-Ruiz C, Barron S, Stapleton S, O'Leary D, Fabre A, Quinn C, Nodin B, Jirström K, Bracken A, Gallagher WM. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-08-31.

Abstract P5-08-30: Androgen receptor in early breast cancer: Distribution and prognostic value

Purpose:

Androgen receptor (AR) status in breast cancer has received renewed interest over the last years especially in triple-negative disease (TNBC), but the prognostic value is still under debate. The aim of this study was to assess the distribution and prognostic value of AR in early breast cancer patients with or without adjuvant endocrine treatment.

Patients and methods:

AR was assessed on tissue microarray with the AR 441 antibody (Thermo Scientific) on a cohort consisting of 471 patients derived from two clinical studies: (1) 208 premenopausal node-negative patients of which 87% had received no adjuvant medical treatment and (2) 263 estrogen receptor (ER)+ and ER-, node-positive and –negative patients treated with 2 years of adjuvant tamoxifen. Nuclear AR was divided in 5 groups: 0-1%, 2-10%, 11-50%, 51-75%, and 76-100% positive cells, scored as 0-4. Cox proportional hazards regression, stratified by study, was used to model the impact of the prognostic factors on distant disease-free survival (DDFS), both using trend tests and a cut-off for positivity set at >10%, and log-rank tests to compare survival in different strata. Due to non-proportional hazards, the analysis was restricted to the first 5 years after diagnosis, a time period during which 95 patients developed distant recurrences.

Results:

76% of all patients were AR+, and 89%, 48%, and 23% of the ER+, ER-, and TNBC, respectively. Positive associations were observed between AR, ER and progesterone receptor status (PgR), negative associations with Ki67, and histological grade, but no associations with tumour size, age or Human Epidermal Growth Factor Receptor 2 (HER2). In univariable analysis, when divided into 5 groups, AR was a prognostic factor for DDFS with a Hazard Ratio (HR) of 0.86 per step in fraction score (95% Confidence Interval (CI): 0.76-0.98, p=0.018), as was HER2, age, size, grade, node-status, PgR, and ER status. In the Kaplan-Meier curves for each study, a similar but weaker trend was found (log-rank test for trend p=0.14 and 0.057 for cohort 1 and 2, respectively). With a cut-off at 10%, a similar HR was found (HR=0.67, 95% CI:0.43-1.05, p=0.078). In multivariable analysis, adjusted for grade, tumour size, HER2, ER, node-status, and age, AR did not retain independent prognostic value (HR 1.04 95% CI:0.88-1.23, p=0.66). In the TNBC patients there were no significant differences in DDFS in the AR+ vs AR-patients, possibly due to few events and a small population (n=20/75).

Conclusion:

This study demonstrates that AR is a weak prognostic factor for recurrence in a cohort consisting of node-negative premenopausal patients without endocrine treatment and patients who have received adjuvant endocrine treatment. There was however no independent value in multivariable analyses. It is noteworthy that there were 23% AR positive TNBC patients, for whom there is currently no available targeted treatment. There are several ongoing studies with AR-targeted treatment in the metastatic setting, which if proven effective, may be transferred to studies in the adjuvant setting with the goal of improving long-term prognosis for TNBC. Taken together, AR may be clinically helpful for prognostic considerations and for selection of adjuvant treatment.

Citation Format: Werner-Hartman L, Folkesson E, Nodin B, Malmström P, Fernö M, Nimeus E, Klintman M. Androgen receptor in early breast cancer: Distribution and prognostic value. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-08-30.

Membranous expression of podocalyxin-like protein is an independent factor of poor prognosis in urothelial bladder cancer

BACKGROUND

Membranous expression of the anti-adhesive glycoprotein podocalyxin-like (PODXL) has previously been found to correlate with poor prognosis in several major cancer forms. Here we examined the prognostic impact of PODXL expression in urothelial bladder cancer.

METHODS

Immunohistochemical PODXL expression was examined in tissue microarrays with tumours from two independent cohorts of patients with urothelial bladder cancer: n=100 (Cohort I) and n=343 (Cohort II). The impact of PODXL expression on disease-specific survival (DSS; Cohort II), 5-year overall survival (OS; both cohorts) and 2-year progression-free survival (PFS; Cohort II) was assessed.

RESULTS

Membranous PODXL expression was significantly associated with more advanced tumour (T) stage and high-grade tumours in both cohorts, and a significantly reduced 5-year OS (unadjusted HR=2.25 in Cohort I and 3.10 in Cohort II, adjusted HR=2.05 in Cohort I and 2.18 in Cohort II) and DSS (unadjusted HR=4.36, adjusted HR=2.70). In patients with Ta and T1 tumours, membranous PODXL expression was an independent predictor of a reduced 2-year PFS (unadjusted HR=6.19, adjusted HR=4.60) and DSS (unadjusted HR=8.34, adjusted HR=7.16).

CONCLUSION

Membranous PODXL expression is an independent risk factor for progressive disease and death in patients with urothelial bladder cancer.

A cohort study of the prognostic and treatment predictive value of SATB2 expression in colorectal cancer

BACKGROUND

Special AT-rich sequence-binding protein 2 (SATB2) is a novel diagnostic marker of colorectal cancer (CRC), and loss of SATB2 has been linked to poor survival from the disease. In this study, we validated the prognostic ability of SATB2 expression in a large, prospective CRC cohort.

METHODS

Immunohistochemical SATB2 expression was assessed in 527 incident CRC cases from the Malmö Diet and Cancer Study. Kaplan-Meier analysis and Cox proportional hazards modelling were used to explore the impact of SATB2 expression on cancer-specific survival (CSS) and overall survival (OS).

RESULTS

High SATB2 expression was associated with a prolonged CSS in the full cohort (hazard ratio (HR)=0.61; 95% CI 0.41-0.92) and in colon cancer (HR=0.39; 95% CI 0.20-0.75), remaining significant in multivariable analysis of colon cancer (HR=0.49; 95% CI 0.25-0.96), with similar findings for OS. In curatively resected stage III-IV patients, a significant benefit from adjuvant and/or neoadjuvant therapy was observed for SATB2 high tumours (P(interaction)=0.037 for OS) and high SATB2 expression in rectal cancer correlated with an enhanced effect of neoadjuvant therapy (P(interaction)=0.033 for OS).

CONCLUSION

High SATB2 expression is an independent marker of good prognosis in colon cancer and may modulate sensitivity to chemotherapy and radiation.