Could perfusion heterogeneity at dynamic contrast-enhanced MRI be used to predict rectal cancer sensitivity to chemoradiotherapy?

AIM: To evaluate whether perfusion heterogeneity of rectal cancer prior to chemoradiotherapy (CRT) using histogram analysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) quantitative parameters can predict response to treatment. MATERIALS AND METHODS: Twenty-one patients with histologically proven rectal adenocarcinoma were enrolled prospectively. All patients underwent 1.5 T DCE-MRI before CRT. Tumour volumes were drawn on Ktrans and Ve maps, using T2-weighted (W) images as reference, and the following first-order texture parameters of Ve and Ktrans values were extracted: 25th, 50th, 75th percentile, mean, standard deviation, skewness, and kurtosis. After CRT, patients underwent surgery and according with Rödel's tumour regression grade (TRG), they were classified as poor responders "non-GR" (TRG 0-2) and good responders "GR" (TRG 3-4). Differences between GR and non-GR in DCE-MRI first-order texture parameters were evaluated using the Mann-Whitney test, and their role in the prediction of response was investigated using receiver operating characteristic (ROC) curve analysis. RESULTS: Sixteen (76%) patients were classified as GR and five (24%) were non-GR. Skewness and kurtosis of Ve was significantly higher in non-GR (4.886±1.320 and 36.402±24.486, respectively) than in GR patients (1.809±1.280, p=0.003 and 6.268±8.130, p= 0.011). Ve skewness <3.635 was able to predict GR with an area under the ROC curve (AUC) of 0.988, sensitivity 93.8%, specificity 80%, and accuracy 90.5%. Ve kurtosis <21.095 was able to predict response with an AUC of 0.963, sensitivity 93.8%, specificity 80%, and accuracy 90.5%. Other parameters were not different between groups or predictors of response. CONCLUSION: Ve skewness and kurtosis seem to be promising in the prediction of response to CRT in rectal cancer patients.

Randomized, placebo-controlled, double-blind trial of clobetasol propionate 0.05% in the treatment of oral lichen planus.

OBJECTIVE: To perform a randomized, placebo-controlled, double-blind study, with a follow-up period of 6 months, for the use of topical clobetasol in cases of symptomatic oral lichen planus (OLP). SUBJECTS AND METHODS: Thirty-two participants were analyzed, with the aims of: (I) to compare the usefulness of topically applied clobetasol propionate 0.05% (mixed with 4% hydroxyethyl cellulose gel) and 4% hydroxyethyl cellulose gel alone (considered as placebo) in the management of OLP; (II) to describe which of them is quicker in decreasing signs and reported symptoms, and (III) which is able to give the proper longer remission in the follow-up. RESULTS: Symptoms improved in all clobetasol-treated patients during the first 2 months of therapy, while only 50% of placebo control group (p = .005) displayed similar results; of the remaining half, 12.5% did experienced a worsening while 37.5% remained stable. Regarding clinical signs, 87.5% of clobetasol-treated patients improved, while only 62.5% of the placebo-treated patients had a positive response (p = .229). CONCLUSIONS: It is possible to report that clobetasol, at this dosage, has been more effective than a placebo at provoking symptoms improvement in subjects affected by atrophic-erosive oral lesions.

Hippocampal SPARC regulates depression-related behavior.

SPARC (secreted protein acidic and rich in cysteine) is a matricellular protein highly expressed during development, reorganization and tissue repair. In the central nervous system, glial cells express SPARC during development and in neurogenic regions of the adult brain. Astrocytes control the glutamate receptor levels in the developing hippocampus through SPARC secretion. To further characterize the role of SPARC in the brain, we analyzed the hippocampal-dependent adult behavior of SPARC KO mice. We found that SPARC KO mice show increased levels of anxiety-related behaviors and reduced levels of depression-related behaviors. The antidepressant-like phenotype could be rescued by adenoviral vector-mediated expression of SPARC in the adult hippocampus, but anxiety-related behavior persisted in these mice. To identify the cellular mechanisms underlying these behavioral alterations, we analyzed neuronal activity and neurogenesis in the dentate gyrus (DG). SPARC KO mice have increased levels of neuronal activity, evidenced as more neurons that express c-Fos after a footshock. SPARC also affects cell proliferation in the subgranular zone of the DG, although it does not affect maturation and survival of new neurons. SPARC expression in the adult DG does not revert the proliferation phenotype in KO mice, but our results suggest a role of SPARC in limiting the survival of new neurons in the DG. This work suggests that SPARC could affect anxiety-related behavior by modulating neuronal activity, and that depression-related behavior is dependent upon the adult expression of SPARC, which affects adult brain function by mechanisms that need to be elucidated.