Tubal and ovarian pathways to pelvic epithelial cancer: a pathological perspective.

Prolongation of ovarian epithelial cancer survival depends on early detection or improved responses to chemotherapy. Gains in either have been modest at best. Understanding the diverse pathogenesis of this disease is critical to early intervention or prevention. This review addresses six important variables, including (i) cell of origin, (ii) site of origin, (iii) initial genotoxic events, (iv) risks imposed by hereditary and other promoting conditions, (v) subsequent factors that promote different patterns of metastatic spread, and (vi) prospects for intervention. This review proposes two distinct pathways to pelvic epithelial cancer. The first initiates in ovarian surface epithelium (OSE), Mullerian inclusions or endometriosis in the ovary. The second arises from the endosalpinx and encompasses a subset of serous carcinomas. The serous carcinogenic sequence in the distal fallopian tube is described and contrasted with lower grade serous tumors based on tumour location, earliest genetic change and ability (or lack of) to undergo terminal (ciliated) differentiation. Ultimately, a clear understanding of tumour origin and the mechanism(s) leading to the earliest phases of the serous and endometrioid carcinogenic sequences may hold the greatest promise for designing prevention strategies and/or developing new therapies.

Vitamin D analogs as anti-carcinogenic agents.

Deltanoids are the class of compounds comprising all natural and synthetic vitamin D molecules. The anti-proliferative, pro-differentiation, and pro-apoptotic properties of deltanoids have garnered interest in the fields of cancer chemoprevention and chemotherapy. The naturally occurring, biologically active form of vitamin D, 1,25(OH)2D3, causes hypercalcemia at pharmacologically relevant doses which forms a major obstacle in the clinical development of this compound. Design of new deltanoids has shown promise in separating the beneficial effects from the toxic effects. The Vitamin D receptor (VDR) is a major target for deltanoid design, and the structural features of deltanoid binding have been described. Effective compounds must also exhibit beneficial pharmacokinetic properties in vivo, and the plasma vitamin D binding protein (DBP) is likely to play an important role in the success of deltanoids in the clinic. Further, dual strategies of avoiding vitamin D toxicity through altering the dosing schedule and using less toxic deltanoids are in development. The three main categories of structural modification to the vitamin D backbone include the C,D-ring, the A-ring, and the C,D-ring side chain, and the ways each area has impacted efficacy and toxicity have been described through structure-activity relationships (SARs). Lastly, there is evidence that deltanoids can enhance the activity of other chemopreventive agents. The use of a cocktail approach will be discussed as a potential avenue for deltanoids in chemoprevention and chemotherapy.