Infertility is a dramatic and frequent side effect in women who are undergoing chemotherapy. Actual strategies are mainly focused on oocyte cryopreservation, but this is not always a suitable option. Considering the key role that granulosa cells play in follicle life, we studied whether thyroid hormone 3,5,3′-triiodothyronine (T₃) protects rat ovarian granulosa cells from chemotherapy-induced apoptosis. To this aim, a cell line was established from fresh isolated rat granulosa cells and named rGROV. Cells were exposed to paclitaxel (PTX) and T₃, and apoptosis, cell viability, and cell cycle distribution were analyzed under different conditions. First, the integrity of the steroidogenic pathway was demonstrated, and the presence of thyroid receptors, transporters, and deiodinases was confirmed by quantitative PCR. Cells were then exposed to PTX alone or contemporary to T₃. MTT and TUNEL assays revealed that while there was a relevant percentage of dying cells when exposed to PTX (40–60%), the percentage was sensibly reduced (20–30%) in favor of living cells if T₃ was present. Cell cycle analysis showed that cells exposed to PTX alone were first collected in G2 and then died by apoptosis; on the other hand, the T₃ granted the cells to cycle regularly and survive PTX insult. In addition, western blot and FCM analyses confirmed that caspases activation, casp 3 and Bax, were downregulated by T₃ and that Bcl2 and cyclins A and B together with cdk1 were upregulated by T₃. In conclusion, we demonstrated that thyroid hormone T₃ can counteract the lethal effect of taxol on granulosa cells.

The pancreatic adenocarcinoma is an aggressive and devastating disease, which is characterized by invasiveness, rapid progression, and profound resistance to actual treatments, including chemotherapy and radiotherapy. At the moment, surgical resection provides the best possibility for long-term survival, but is feasible only in the minority of patients, when advanced disease chemotherapy is considered, although the effects are modest. Several studies have shown that thyroid hormone, 3,3′,5-triiodo-l-thyronine (T₃) is able to promote or inhibit cell proliferation in a cell type-dependent manner. The aim of the present study is to investigate the ability of T₃ to reduce the cell growth of the human pancreatic duct cell lines chosen, and to increase the effect of chemotherapeutic drugs at conventional concentrations. Three human cell lines hPANC-1, Capan1, and HPAC have been used as experimental models to investigate the T₃ effects on pancreatic adenocarcinoma cell proliferation. The hPANC-1 and Capan1 cell proliferation was significantly reduced, while the hormone treatment was ineffective for HPAC cells. The T₃-dependent cell growth inhibition was also confirmed by fluorescent activated cell sorting analysis and by cell cycle-related molecule analysis. A synergic effect of T₃ and chemotherapy was demonstrated by cell kinetic experiments performed at different times and by the traditional isobologram method. We have showed that thyroid hormone T₃ and its combination with low doses of gemcitabine (dFdCyd) and cisplatin (DDP) is able to potentiate the cytotoxic action of these chemotherapic drugs. Treatment with 5-fluorouracil was, instead, largely ineffective. In conclusion, our data support the hypothesis that T₃ and its combination with dFdCyd and DDP may act in a synergic way on adenopancreatic ductal cells.