Abstract 36P
Background
Adrenocortical carcinoma (ACC) is a rare and aggressive tumor with a dismal prognosis. The pharmacotherapy of ACC is based on mitotane with/without etoposide, doxorubicin, and cisplatin. The limited efficacy and the toxicity of this treatment require new drug strategies. Progesterone (Pg) is a lipophilic hormone involved in both physiological and pathological processes. Trabectedin (T) is an alkylating drug with a complex mechanism of action. We have already reported Pg and T cytotoxicity in ACC cells, involving the Wnt/β-catenin pathway. Here, we investigated their effect on ACC cells invasiveness and metastatization.
Methods
Cell lines of primary (NCI-H295R) and metastatic (MUC-1 and TVBF-7) ACC were used to study the in vivo efficacy of Pg and T, by establishing tumor xenografts in Danio rerio embryos. The tumor mass areas were evaluated as well as metastasis-positive embryos. The in vitro invasiveness was evaluated in transwell assay. MMP2 (metalloprotease 2) secretion and activity were evaluated by western-blot and by zymography in cell culture-conditioned media.
Results
Xenograft experiments demonstrated Pg- and T-related reduction of tumor area in each ACC cell mode. Metastasis-derived cells proved to be able to metastasize in different regions of the embryos. Metastasis formation was reduced after Pg and T (Table). These results were confirmed in vitro, where Pg and T reduced the invasiveness of ACC cells across the matrix, which was greater at baseline for the metastatic models compared to primary-derived one. In metastatic models, protein analysis demonstrated a reduction of MMP2 secretion and activity in the culture medium after Pg and T exposure.
Table: 36P
Percentage of xenografted zebrafish embryos with metastasis
| ACC cell line | % of embryos with metastasis ± SD | |||
| Untreated | Pg-treated | Untreated | T-treated | |
| MUC-1 | 62.50 % ± 9.60% | 10.80 % ± 0.85% (p<0.05) | 72.15 % ± 9.65% | 24.20 % ± 3.52% (p<0.05) |
| TVBF-7 | 12.07 % ± 7.31% | No metastasis | 12.07% ± 7.31% | 1.19% ± 2.06% |
Conclusions
Our results indicate the ability of Pg and T to interfere with invasive and metastasis processes, with an involvement of MMP2. Furthermore, these results support those previously published and reinforce the promising role of Pg and T in ACC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Fondazione AIRC per la ricerca sul cancro (IG 23009; P.I. Prof. Alfredo Berruti - IG 27233 P.I. Prof. Sandra Sigala) University of Brescia (local grants) Trabectedin was kindly given by PharmaMar S.A. (Madrid, Spain).
Disclosure
A. Berruti: Financial Interests, Personal, Invited Speaker: HRA; Financial Interests, Personal, Advisory Board: HRA; Financial Interests, Personal, Research Grant: Janssen, Sanofi, Novartis. All other authors have declared no conflicts of interest.