HPV L1 detection discriminates cervical precancer from transient HPV infection: a prospective international multicenter study.

The benefits of cytology-based cervical cancer screening programs in reducing morbidity and mortality are well recognized. Especially, overtreatment of human papillomavirus (HPV) high-risk positive early dysplastic lesions may have a negative impact on reproductive outcomes for fertile women. To optimize the clinical management an objective standard is needed to distinguish precancer that requires treatment, from spontaneously resolving HPV infections. In the current study, we examined the prognostic relevance of HPV-L1 capsid protein analysis with Cytoactiv in an international prospective multicenter study including 908 HPV high-risk positive early dysplastic lesions (LSIL/HSIL) during a follow-up period of 54 months. The clinical end points of the study were histologically confirmed CIN3+ as progression, CIN1/2 for stable disease and repeated negative Pap smears as spontaneous clinical remission. The difference of the clinical outcome of HPV-L1-negative and HPV-L1-positive cases was statistically highly significant (P-value<0.0001) independent of the classification as mild dysplasia (LSIL) and moderate dysplasia (HSIL). Of the HPV-L1-negative HPV high-risk positive mild/moderate dysplasias 84% progressed to CIN3, as compared with only 20% of the HPV-L1-positive cases. The data from our study show that HPV-L1 detection allows to identify transient HPV infections and precancerous lesions within the group of HPV high-risk positive early dysplastic lesions. The high progression rate of HPV-L1-negative mild and moderate dysplasia emphasizes the precancerous nature of these lesions. A close follow-up with colposcopy and histological evaluation is advisable and removal of these lesions should be considered. The low malignant potential of HPV-L1-positive cases, however, indicates transient HPV infection, justifying a watch and wait strategy with cytological follow-up, thus preventing overtreatment especially for women in their reproductive age.

Propiverine and metabolites: differences in binding to muscarinic receptors and in functional models of detrusor contraction.

Propiverine is a commonly used antimuscarinic drug used as therapy for symptoms of an overactive bladder. Propiverine is extensively biotransformed into several metabolites that could contribute to its spasmolytic action. In fact, three propiverine metabolites (M-5, M-6 and M-14) have been shown to affect various detrusor functions, including contractile responses and L-type calcium-currents, in humans, pigs and mice, albeit with different potency. The aim of our study was to provide experimental evidence for the relationship between the binding of propiverine and its metabolites to human muscarinic receptor subtypes (hM(1)-hM(5)) expressed in chinese hamster ovary cells, and to examine the effects of these compounds on muscarinic receptor-mediated detrusor function. Propiverine, M-5, M-6 and M-14 bound to hM(1)-hM(5) receptors with the same order of affinity for all five subtypes: M-6 > propiverine > M-14 > M-5. In HEK-293 cells expressing hM(3), carbachol-induced release of intracellular Ca(2+) ([Ca(2+)](i)) was suppressed by propiverine and its metabolites; the respective concentration-response curves for carbachol-induced Ca(2+)-responses were shifted to the right. At higher concentrations, propiverine and M-14, but not M-5 and M-6, directly elevated [Ca(2+)](i). These results were confirmed for propiverine in human detrusor smooth muscle cells (hDSMC). Propiverine and the three metabolites decreased detrusor contractions evoked by electric field stimulation in a concentration-dependent manner, the order of potency being the same as the order of binding affinity. We conclude that, in comparison with the parent compound, loss of the aliphatic side chain in propiverine metabolites is associated with higher binding affinity to hM(1)-hM(5) receptors and higher functional potency. Change from a tertiary to a secondary amine (M-14) results in lower binding affinity and reduced potency. Oxidation of the nitrogen (M-5) further lowers binding affinity as well as functional potency.