instruction:
In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
question:
Context: The modern multimodality therapeutic approach to Wilms tumor (WT), combining surgery with radiotherapy and chemotherapy results in high cure rates even for high stage disease. However, the combination of radiotherapy and chemotherapy is associated with severe early and late complications such as neutropenic sepsis, growth retardation and secondary malignancies. Therefore, novel therapeutic strategies, which would decrease the treatment burden, are required. We studied the expression of erbB2 growth factor receptor in WT cells as well as its role as a tumor therapeutic target in an in vivo xenograft model of Wilms tumor.', 'Paraffin embedded pathological samples from 14 different WT cases as well as xenografts derived thereof were immunostained with anti-erbB2 monoclonal antibody. The immunostaining was graded in comparison to a known positive control (breast cancer) and was scored by the intensity of staining (0 to +3) multiplied by the percentage of cells expressing the antigen. The expression of erbB2 in the human WT xenograft was verified also by fluorescence activated cell sorter analysis. In addition, nude mice bearing established subcutaneous human WT xenografts were treated with either 3 intraperitoneal injections of N29 anti-erbB2 monoclonal antibody or irrelevant antibody.', 'All of the authentic human pathological samples, except 1 anaplastic WT as well the WT xenografts (at different stages), expressed erbB2. Expression was also observed in WT metastasis and in tumors which out grew chemotherapy. Systemic administration of anti-erbB2 monoclonal antibody inhibited and even prevented the growth of WT xenograft in vivo.\Question: Is erbB2 a tumor associated antigen and a suitable therapeutic target in Wilms tumor?
answer:
ErbB2 is a tumor associated antigen in WT. Being expressed in almost all tumor stages, our in vivo model suggests that erbB2 may serve as a WT therapeutic target. Further work is needed to establish the role of erbB2 in the disease and its potential use in decreasing current treatment burden.


question:
Context: The quantity of the silver-stained nucleolar proteins (AgNOR proteins) measured in situ in cytohistologic preparations is related to the rapidity of cell proliferation. The term "AgNOR proteins" comprises several proteins. The relationship between the individual AgNOR protein amount and cell proliferating activity is not yet known. We studied the quantitative distribution of the individual AgNOR proteins, with specific attention to the two major AgNOR proteins, nucleolin and protein B23, in seven human cancer cell lines characterized by different cell doubling times.', 'The doubling time of cancer cells was measured by counting the asynchronously growing cells at regular time intervals. The AgNOR proteins were quantified in situ, after a specific one-step staining procedure, by computerized image analysis. For the quantitative evaluation of nucleolin and protein B23, two methods were followed. Nuclear proteins after separation by SDS-PAGE were transferred onto nitrocellulose membranes and were either: 1) stained by the silver staining procedure for AgNOR proteins or 2) treated with anti-nucleolin and anti-protein B23 mAb followed by reaction with secondary Ab linked to peroxidase and revealed by chemiluminescence and autoradiography. In both cases, measurement of individual AgNOR protein and nucleolin and protein B23 amount was carried out using computerized densitometric analysis.', 'Integrated density values of the silver-stained bands at 105 kDa (nucleolin) and 38 to 39 kDa (protein B23) represented, in all cell lines, more than 60% of the total silver-stained band value. A relationship was found between the densitometric values of silver-stained nucleolin and protein B23 and rapidity of cell proliferation (r = 0.85 and r = 0.86, respectively, p < 0.05). The values of nucleolin and protein B23 obtained using the Western blots were strictly related to the rapidity of cell proliferation (r = 0.93 and 0.96, respectively, p < 0.001). Finally, a good correlation was observed between the mean AgNOR protein area value, as defined in cytologic preparations in situ, and nucleolin and protein B23 amounts as evaluated in silver-stained nitrocellulose membranes (r = 0.92 and r = 0.90, respectively, p < 0.01) and in Western blots (r = 0.95 and r = 0.94, respectively, p < 0.001).\Question: Is the quantity of nucleolar proteins nucleolin and protein B23 related to cell doubling time in human cancer cells?
answer:
These data indicate that the quantitative changes of AgNOR proteins observed in cytohistologic preparations in situ mainly reflect the quantitative changes of nucleolin and protein B23 and demonstrate that nucleolin and protein B23 amounts are inversely related to cell doubling time in human cancer cells.


question:
Context: Liver fibrosis develops when hepatic stellate cells (HSC) are activated into collagen-producing myofibroblasts. In non-alcoholic steatohepatitis (NASH), the adipokine leptin is upregulated, and promotes liver fibrosis by directly activating HSC via the hedgehog pathway. We reported that hedgehog-regulated osteopontin (OPN) plays a key role in promoting liver fibrosis. Herein, we evaluated if OPN mediates leptin-profibrogenic effects in NASH.', 'Leptin-deficient (ob/ob) and wild-type (WT) mice were fed control or methionine-choline deficient (MCD) diet. Liver tissues were assessed by Sirius-red, OPN and αSMA IHC, and qRT-PCR for fibrogenic genes. In vitro, HSC with stable OPN (or control) knockdown were treated with recombinant (r)leptin and OPN-neutralizing or sham-aptamers. HSC response to OPN loss was assessed by wound healing assay. OPN-aptamers were also added to precision-cut liver slices (PCLS), and administered to MCD-fed WT (leptin-intact) mice to determine if OPN neutralization abrogated fibrogenesis.', 'MCD-fed WT mice developed NASH-fibrosis, upregulated OPN, and accumulated αSMA+ cells. Conversely, MCD-fed ob/ob mice developed less fibrosis and accumulated fewer αSMA+ and OPN+ cells. In vitro, leptin-treated HSC upregulated OPN, αSMA, collagen 1α1 and TGFβ mRNA by nearly 3-fold, but this effect was blunted by OPN loss. Inhibition of PI3K and transduction of dominant negative-Akt abrogated leptin-mediated OPN induction, while constitutive active-Akt upregulated OPN. Finally, OPN neutralization reduced leptin-mediated fibrogenesis in both PCLS and MCD-fed mice.\Question: Is osteopontin a proximal effector of leptin-mediated non-alcoholic steatohepatitis ( NASH ) fibrosis?
answer:

OPN overexpression in NASH enhances leptin-mediated fibrogenesis via PI3K/Akt. OPN neutralization significantly reduces NASH fibrosis, reinforcing the potential utility of targeting OPN in the treatment of patients with advanced NASH.