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ERα function is crucial for the development of normal mammary gland as well as in the process of progression of breast cancer cells. Signals that target receptor levels contribute to regulate estrogens effects in the cells. An intricate cross-regulation has been documented between ERα and TGF-β down-stream molecules: SMAD2, SMAD3, and SMAD4, that can bind ERα and regulate their signaling. Thus, identification of natural anticancer drugs able to influence the latter molecule might provide alternative choices for breast cancer treatment. Taking into account our previous published data we wanted to study the effect of 5-Methoxypsoralen (bergapten) on ERα and on TGF-β pathway. We reported that bergapten, a coumarin containing compound, effectively depletes ERα in MCF-7 breast cancer sensitive cells and in tamoxifen-resistant clone. The decrease of ERα protein after bergapten treatment results from the ubiquitine-proteasome pathway as demonstrated by the use of MG-132. IP experiments with ER antibody, demonstrated that the protein has physical interaction with SMAD4 and poly-ubiquitine and the amount of ubiquitinated receptor, linked to SMAD4, is greater under bergapten. The crucial role played by SMAD4, in this process, emerges from the observation that in breast cancer cells, silencing of SMAD4, resulted in increased expression of endogenous ERα in both control and bergapten-treated cells, compared to wild- type cells. The same results were confirmed in siRNA TGF-β RII cells. The results suggest a novel negative regulation of ERα by TGF-β/SMAD4 in breast cancer cells and indicate that the SMAD4 protein is involved in the degradation of ERα induced by bergapten. We propose that bergapten may efficiently act as a natural antitumoral agent, able to deplete ERα from breast cancer tamoxifen-sensitive and resistant cells, thereby retraining the effect of membrane signals targeting ERα and in such way its mitogenic potentiality.

Progesterone (P), 17-OH-progesterone (17-OH-P), androstenedione (A), dehydroepiandrosterone (DHEA), testosterone (T), 5 alpha-dihydrotestosterone (5 alpha-DHT), and 17 beta-estradiol (E2) were measured by RIA in plasma and testes of 114 males of the oviparous lizard Podarcis s. sicula raf, a species that displays annual hibernating cycles. Hormones were determined each month from January until December, except for August. Testosterone peaked at 174.8 ng/ml of plasma after emergence (March), while 5 alpha-DHT and A peaked in April. Plasma DHEA increased during hibernation. During the refractory period there were progressive increases in P and E2 plasma levels. The testicular peak of T, in March, coincided with that observed in plasma. The striking increases in testicular T and A in early July occurred at a time when plasma androgen concentrations were low. 5 alpha-DHT increased in April when spermatogenesis with spermiation occurred and then decreased alongside a second peak of T. There is an apparent separation of plasma and testicular androgen concentrations during the reproductive cycle.

Adverse reactions, toxicity, and poor compliance from patients still represent major challenges for conventional chemotherapy treatments. Localized drug delivery would ideally improve therapeutic efficacy, minimizing the side effects. An MSU-type mesoporous silica-based nanodevice (FOL-MSN-BTZ), able to selectively deliver the antineoplastic drug bortezomib (BTZ) to folate receptor over-expressing multiple myeloma (FR+ MM) cells is described. The receptor-specific ligand, folic acid, grafted on the external surface of the nanosystem, allows tumor recognition and cell internalization, while BTZ, mainly linked to the pore internal surface through a covalent pH-sensitive bond, is released in an acidic tumor environment. A detailed investigation showed that only the fine balancing of different functionalities of the nanodevice around the external and internal surfaces of MSN particles shows the absence of toxicity towards healthy cells in vitro and negligible BTZ-release at physiological pH, which are suitable features for applicative purposes in the engineering of therapies. After complete characterization in vitro, an accurate suspendability assessment, which considered the sedimentation process that reduces the particle amount and, consequently, drug content in the suspensions, allowed the development of an injectable formulation of FOL-MSN-BTZ that showed higher antitumor efficacy and an overall tendency to lower toxicity in a MM mice model compared to the conventional bortezomib chemotherapy.

// Francesca De Amicis 1, 2 , Carmela Guido 1, 2 , Marta Santoro 1 , Francesca Giordano 2 , Ada Dona 1, 2 , Pietro Rizza 2 , Michele Pellegrino 2 , Ida Perrotta 3 , Daniela Bonofiglio 1, 2 , Diego Sisci 1, 2 , Maria Luisa Panno 2 , Donatella Tramontano 4 , Saveria Aquila 1, 2, * , Sebastiano Ando 1, 2, * 1 Centro Sanitario, University of Calabria, Rende, Italy 2 Department of Pharmacy, Health Science and Nutrition, University of Calabria, Rende, Italy 3 DiBEST University of Calabria, Rende, Italy 4 Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, Naples, Italy * Joint senior authors Correspondence to: Francesca De Amicis, email: francesca.deamicis@unical.it Sebastiano Ando, email: sebastiano.ando@unical.it Keywords: progesterone, Bcl-2, cell cycle arrest, pRb, p16 Received: February 03, 2016 Accepted: July 09, 2016 Published: July 23, 2016 ABSTRACT Loss of progesterone-receptors (PR) expression is associated with breast cancer progression. Herein we provide evidence that OHPg/PR-B through Beclin-1 evoke autophagy-senescence transition, in breast cancer cells. Specifically, OHPg increases Beclin-1 expression through a transcriptional mechanism due to the occupancy of Beclin-1 promoter by PR-B, together with the transcriptional coactivator SRC-2. This complex binds at a canonical half progesterone responsive element, which is fundamental for OHPg effects, as shown by site-directed mutagenesis. Beside, OHPg via non-genomic action rapidly activates JNK, which phosphorylates Bcl-2, producing the functional release from Beclin-1 interaction. This is not linked to an efficient autophagic flux, since p62 levels, marker of degradation via lysosomes, were not reduced after sustained OHPg stimulus. Instead, the cell cycle inhibitor p27 was induced, together with an irreversible G1 arrest, hallmark of cellular senescence. Specifically the increase of senescence-associated β-galactosidase activity was blocked by Bcl-2 siRNA but also by Beclin-1 siRNA. Collectively these findings support the importance of PR-B expression in breast cancer cells, thus targeting PR-B may be a useful strategy to provide additional approaches to existing therapies for breast cancer patients.

Insulin-like growth factor-I receptor (IGF-IR) overexpression may play a role in prostate cancer progression. We found previously that, in prostate cancer cells, IGF-IR is up-regulated by both androgens and estrogens via a nongenotropic pathway. We now show that, in prostate cancer cells, stimulation with either androgens or estrogens up-regulates IGF-IR by inducing cyclic AMP response element–binding protein (CREB) activation. Both sex steroids phosphorylated CREB at Ser133 in a dose-dependent manner in androgen receptor (AR)–positive LNCaP cells, whereas only estrogens phosphorylated CREB in AR-negative PC3 cells. CREB phosphorylation involved c-Src–dependent extracellular signal-regulated kinase 1/2 activation, but not protein kinase A, protein kinase C, or calmodulin-dependent kinase II, and occurred also in cells transfected with AR or estrogen receptor mutants that do not localize into the nucleus. CREB silencing abrogated IGF-IR up-regulation and promoter activation. We also showed that CREB binds to IGF-IR promoter region and identified the relevant CREB-binding site at the 5′-untranslated region fragment of IGF-IR promoter. In conclusion, we describe a novel mechanism of IGF-IR up-regulation and promoter activity by CREB activation, induced by sex steroids, through a nongenotropic signaling. [Cancer Res 2009;69(18):7270–7]

Progesterone, 17-hydroxyprogesterone, androstenedione, 5 alpha-dihydrotestosterone, dehydroepiandrosterone, testosterone and oestradiol concentrations in the plasma were measured by simultaneous radioimmunoassay in males of the lizard Podarcis s. sicula. Hormonal determinations were performed at monthly intervals from January to December (except for August). Testosterone and androstenedione reached peak values of 174.8 ng/ml and 21.4 ng/ml in the mating season (spring) and then testosterone fell abruptly to 5.9 ng/ml in June remaining at this level during hibernation when dehydroepiandrosterone (DHA) reached a maximal level of 28.5 +/- 9.3 ng/ml. Castration resulted in a marked decrease of testosterone, androstenedione, dihydrotestosterone and DHA values, with DHA being significantly lowered only during the winter season. In castrated animals, however, testosterone and androstenedione persisted conspicuously in the plasma during the breeding period, suggesting that adrenal sex steroid output may change during the annual reproductive cycle. In intact animals, progesterone and oestradiol exhibited peak values during the refractory period after the mating season. We suggest a probable role of oestradiol in the induction of the refractory period in this lizard.