16alpha-hydroxyestrone inhibits estrogen sulfotransferase activity in human liver cancer cells.

In this study we investigated the impact of estrogen antagonists and of 16alpha-OHE1 (an estrogen derivative that binds to and induces transactivation of estrogen receptors) on estrogen metabolism in malignant HepG2 human liver cells featured by high estrogen sulfotransferase (EST); our aim was to clarify the potential correlation of EST and ER. As expected, the HepG2 cells exhibited a very high EST activity, with the majority of estrogen metabolites (over 86%) being detected as sulfates by 24 h. The coincubation of E2 and the antiestrogen tamoxifen induced a weak inhibition of EST activity (from 85.4% to 81.5%), while the coincubation with the pure antagonist ICI-182 and with 16alpha-OHE1 produced a 50% and 90% decrease of EST, respectively. Interestingly, both selective estrogen receptor modulators (SERMs) TAM and ICI-182, along with the same 16alpha-OHE1, gave rise respectively to a 2.8%, 3.2%, and 4.6% of de novo 16alpha-OHE1 formation. The inhibition of EST and the increase of 16alpha-OHE1 formation were both time- and dose-dependent. Our results suggest that EST activity is tightly associated with ER transactivation and can be regulated by selective estrogen receptor modulators (SERMs), including antiestrogens and 16alpha-OHE1. In this framework, 16alpha-OHE1 may have a potential role in human liver carcinogenesis, also through the inhibition of EST and the production of unconjugated, bioavailable estrogens.

Aromatase and amphiregulin are correspondingly expressed in human liver cancer cells.

Human hepatocellular carcinoma (HCC) is associated with high mortality rates, being the third most common cause of cancer death worldwide. Although estrogens have been implicated in HCC, their potential role in development and/or progression of this malignancy remains unclear. In this study we investigated mRNA and protein expression of aromatase (Aro) and amphiregulin (AREG) in relation to estrogen receptors (ERs), in HepG2, Huh7, and HA22T human malignant liver cell lines, using RT-PCR and Western blot analyses. Aro expression was significantly higher (approximately 13-fold, P= 0.003) in HepG2 cells than in Huh7 cells, while no Aro expression could be detected in HA22T cells. Interestingly, the patterns of AREG expression were consistently associated with those of Aro, with approximately 3-fold and approximately 8-fold higher levels being seen in HepG2 cells than in Huh7 cells (P= 0.002) and HA22T cells (P= 0.0014), respectively. Using a specific set of primers, ERalpha46 is the only ER variant expressed in all cell lines, while the wild-type ERalpha66 could not be detected. Western blot analysis revealed a corresponding figure. This evidence suggests that AREG expression may be upregulated by estrogens in human HCC and that locally elevated aromatase activity also may increase malignant cell proliferation through AREG signaling.

CCR5 proinflammatory allele in prostate cancer risk: a pilot study in patients and centenarians from Sicily .

Prostate cancer (PCa) is the most common malignant neoplasm in older men in Western countries. The number of affected older men is increasing. Therefore, strategies for prevention of prostate cancer are crucial. To this purpose it is essential to know the mechanisms involved in development and progression of this malignancy. Recently, an increasing body of genetic and epidemiological studies proposed new hypotheses for prostate carcinogenesis. It has been suggested that genetic factors as well as exposure to environmental factors such as infectious agents, dietary carcinogens, and hormonal imbalances participate in PCa development. Besides, chronic inflammation plays a key role in PCa. Taking into consideration this complex scenario, in the present study we evaluated whether CCR5Delta32 deletion of CCR5 gene might be associated with PCa susceptibility. For the control group we used centenarians, since they represent a disease-free human model. These preliminary results suggest that the CCR5Delta32 anti-inflammatory variant might be a resistance factor for the development of PCa.

HER2/neu expression in relation to clinicopathologic features of breast cancer patients.

We have evaluated HER2/neu expression in 1,355 breast cancer patients recruited at the Breast Cancer Registry in Palermo between January 1999 and December 2004. In this retrospective study, HER2/neu expression was related to clinicopathologic features of the disease, including tumor size, nodal and menopausal status, estrogen and progesterone receptors. Statistical analysis on all 1,355 patients showed a significant correlation between HER2/neu and nodal status (P < 0.001), and a significant association between HER2/neu overexpression and estrogen and progesterone receptors status (P < 0.001). In 194 patients without metastasis, with an average follow-up > or =5 years, only HER2/neu 3+ and histopathologic grading G3 were significantly associated with overall survival.

Expression levels and clinical-pathological correlations of HER2/neu in primary and metastatic human breast cancer.

In this retrospective study we assessed the expression of the HER2/neu oncogene product in a series of 574 consecutive breast cancer cases, all recruited at the Maurizio Ascoli Cancer Center of Civico Hospital, in Palermo, between January 1998 and June 2003. The HER2/neu expression was evaluated using immunohistochemistry and scored from 0 to +3 as per FDA recommendations. The HER2/neu expression levels were related to the clinical-pathological features of the disease, including tumor size, nodal and menopausal status, estrogen and progesterone receptors, and hormonal or chemotherapeutic treatment. In 108 patients with a follow-up period of 3 years or more, the HER2/neu expression was also related to their survival characteristics. A significant correlation (P = 0.011) between HER2/neu +3 and estrogen receptor-negative cases was observed in the 487 M0 patients. In addition, HER2/neu +3 cases were associated with a positive nodal status (57.4%), although this association was not quite significant (P = 0.06). More importantly, follow-up data revealed that, in the 91 M0 patients with an average follow-up period of 37 months, the percentage of HER2/neu +3 patients who relapsed was remarkably greater (54.8%) than that observed for the HER2/neu +1/0 cases when combined (34.2%). Furthermore, the disease-free interval (DFI) was 47 months in the HER2/neu +1/0 group, while it dropped to 45 months in c-HER2/neu +3 cases. Although the limited number of cases does not allow us to draw any definitive conclusions, our data suggest that high expression levels of HER2/neu +3 are associated with an early relapse and a shorter disease-free interval in M0 breast cancer patients.

Estrogen regulates cytokine production and apoptosis in PMA-differentiated, macrophage-like U937 cells.

We have investigated the effects of sex steroids, estradiol (E2), and testosterone (T) on the synthesis of tumor necrosis factor alpha (TNF-alpha) and interleukin-10 (IL-10) in phorbol-myristate-acetate (PMA)-differentiated human monoblastic U937 cells. The ability of both hormones to modulate the viability and programmed cell death of macrophage-like PMA-differentiated U937 cells was also inspected. E2 increased TNF-alpha synthesis, whereas T had no effect on the production of this cytokine. The combination of E2 and its antagonist tamoxifen or ICI-182,789 completely abolished the induction of TNF-alpha, while combination of T and its antagonist Casodex (CSDX) did not significantly affect TNF-alpha production by U937 cells. Exposure of cells to E2 resulted in a dose-dependent decrease of IL-10 synthesis, while again T did not show any detectable effect. In addition, E2 induced a significant increase of apoptosis in macrophage-like U937 cells and this increase was inhibited by the simultaneous addition of either tamoxifen or ICI-182. In contrast, T alone or in combination with CSDX did not modify apoptotic rates of U937 cells. This evidence, taken together, suggests that estrogens, but not androgens, exert a pro-inflammatory action through the modulation of TNF-alpha and IL-10, and regulate the immune effector cells by the induction of programmed cell death.