Sub-cellular population imaging tools reveal stable apical dendrites in hippocampal area CA3.

Anatomically segregated apical and basal dendrites of pyramidal neurons receive functionally distinct inputs, but it is unknown if this results in compartment-level functional diversity during behavior. Here we imaged calcium signals from apical dendrites, soma, and basal dendrites of pyramidal neurons in area CA3 of mouse hippocampus during head-fixed navigation. To examine dendritic population activity, we developed computational tools to identify dendritic regions of interest and extract accurate fluorescence traces. We identified robust spatial tuning in apical and basal dendrites, similar to soma, though basal dendrites had reduced activity rates and place field widths. Across days, apical dendrites were more stable than soma or basal dendrites, resulting in better decoding of the animal's position. These population-level dendritic differences may reflect functionally distinct input streams leading to different dendritic computations in CA3. These tools will facilitate future studies of signal transformations between cellular compartments and their relation to behavior.

Immunohistochemical localization of prolactin receptor (PRLR) to Hodgkin's and Reed-Sternberg cells of Hodgkin's lymphoma.

Prolactin receptor (PRLR), a type-1 cytokine receptor, is overexpressed in a number of cancer types. It has attracted much attention for putative pro-oncogenic roles, which however, remains controversial in some malignancies. In this study, we reported the localization of PRLR to the Hodgkin's and Reed-Sternberg (HRS) cells of Hodgkin's lymphoma (HL), a neoplasm of predominantly B cell origin. Immunohistochemistry performed on 5-µm thick FFPE sections revealed expression of PRLR in HRS cells. Cellular immunofluorescence experiments showed that the HL-derived cell lines, Hs445, KMH2 and L428 overexpressed PRLR. The PRLR immunofluorescent signal was depleted after treating the cell lines with 10 µM of siRNA for 48 h. We also tested whether PRLR is involved in the growth of HL, in vitro. One-way analysis of variance (ANOVA) on cell growth data obtain from WST-1 cell proliferation assay and trypan blue exclusion assay and hemocytometry showed that siRNA-depletion of PRLR expression resulted in decreased growth in all three cell lines. These results offered only a short insight into the involvement of PRLR in HL. As a result, further investigation is required to decipher the precise role(s) of PRLR in the pathogenesis of HL.

Luteolin Induces Cytotoxicity in Mix Cellularity Classical Hodgkin's Lymphoma via Caspase Activated-cell Death.

BACKGROUND/AIM: We investigated the effects of luteolin (LUT) on classical Hodgkin's lymphoma (cHL), since such studies in malignant lymphomas are lacking. MATERIALS AND METHODS: Effect of LUT on cell growth was assessed with water-soluble tetrazolium 1 (WST-1) cell proliferation assay and automated hemocytometry on trypan blue-exclusion assay. Cell death was investigated with acridine orange/ethidium bromide live-dead assay, propidium iodide (PI) flow cytometry, and Annexin-V-PI microscopy. Caspase activation was studied using CellEvent Caspase-3/7 Green detection reagent. High resolution immunofluorescence microscopy was used to detect cleaved-PARP-1. RESULTS: LUT induced a dose-dependent decrease in the growth of KMH2 and L428 cells, cellular models of mix-cellularity (MC) and nodular sclerosis (NS) cHL, respectively. However, LUT induced cell death only in KMH2, at a higher concentration, and this was associated with caspase activation and cleaved PARP-1. CONCLUSION: LUT induces cytotoxicity in the MC-cHL cellular model KMH2 via caspase activation.