No abstract

Colorectal cancer (CRC) is a leading cause of death in the United States. Despite its slow development and the capacity for early diagnosis, current preventive approaches are not sufficient. However, a role for estrogen has been demonstrated in multiple epidemiologic studies, which may benefit CRC prevention. A large body of evidence from preclinical studies indicates that expression of the estrogen receptor beta (ERβ/ESR2) demonstrates an inverse relationship with the presence of colorectal polyps and stage of tumors, and can mediate a protective response. Natural compounds, including phytoestrogens, or synthetic ERβ selective agonists, can activate or upregulate ERβ in the colon and promote apoptosis in preclinical models and in clinical experience. Importantly, this activity has been associated with a reduction in polyp formation and, in rodent models of CRC, has been shown to lower incidence of colon adenocarcinoma. Collectively, these findings indicate that targeted activation of ERβ may represent a novel clinical approach for management of colorectal adenomatous polyps and prevention of colorectal carcinoma in patients at risk for this condition. In this review, we discuss the potential of new chemopreventive or dietary approaches based on estrogen signaling.

No abstract

No abstract

Therapeutic management of Helicobacter pylori (H. pylori) remains an unsolved issue. Indeed, no therapeutic regimen is able to cure the infection in all treated patients, and in many the infection persists despite the administration of several consecutive standard therapies. Although antibiotic resistance reports describe alarming results, the outcome of therapeutic regimens does not seem to parallel this scenario in most cases, since a successful performance is often reached in more than 80% of cases. However, the phenomenon of increasing antibiotic resistance is being closely studied, and the results show controversial aspects even in the same geographic area. For the continents of Europe, America, Asia, Africa, and Oceania, minimal and maximal values of resistance to the main antibiotics (clarithromycin, amoxicillin, metronidazole, and levofloxacin) feature wide ranges in different countries. The real enigma is therefore linked to the several different therapeutic regimens, which show results that often do not parallel the in vitro findings even in the same areas. A first aspect to be emphasized is that some regimens are limited by their use in very small geographic districts. Moreover, not all therapeutic trials have considered bacterial and host factors affecting the therapeutic outcome. The additional use of probiotics may help to reduce adverse events, but their therapeutic impact is doubtful. In conclusion, the "ideal therapy", paradoxically, appears to be a "utopia", despite the unprecedented volume of studies in the field and the real breakthrough in medical practice made by the discovery and treatment of H. pylori. The ample discrepancies observed in the different areas do not encourage the development of therapeutic guidelines that could be valid worldwide. On these bases, one of the main challenges for the future might be identifying a successful solution to overcome antibiotic resistances. In this context, geography must be considered a relevant matter.