TASK DEFINITION: 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.
PROBLEM: Context: An association between mitral valvar prolapse and low body mass index has been proposed. The goal of this study was to evaluate this suggested association using two independent and large databases. For comparison, we evaluated the association, if any, between bicuspid aortic valve and low body mass index.', 'We retrospectively analyzed, using uni- and multivariate analysis, 1742 echocardiograms that were performed as a part of a cardiac screening of teenage athletes and 24,265 echocardiograms performed between 1984 and 1998 for various clinical indications.', 'The first database included a total of 12,926 (53%) female and 11,339 (47%) male patients. The second database included a total of 1172 male (67%) and 570 female (33%) high school athletes. Mitral valvar prolapse was independently associated with low body mass index in addition to mitral regurgitation in both data bases. An index less than 30 occurred in 78 of 13,874 (0.6%) as opposed to 7 of 3236 (0.2%) in the echo data base, p equal to 0.03, odds ratio: 2.4 confidence intervals: 1.1-5.2, and an index less than 20 occurred in 7 of 354 (2%) as opposed to 6 of 944 (0.6%) in the athletic data base, p equal to 0.03, odds ratio: 3.2 confidence intervals: 1.05-9.5. The finding of a bicuspid aortic valve did not have any association with low body mass index.\Question: Is mitral valvar prolapse significantly associated with low body mass index in addition to mitral and tricuspid regurgitation?

SOLUTION: In our two independent databases, mitral valvar prolapse was independently associated with low body mass index in addition to mitral and tricuspid regurgitation. The cause of this association remains unknown.

PROBLEM: Context: This study aims to describe trinitrotoluene (TNT)-induced endoplasmic reticulum stress (ERS) and apoptosis in HePG2 cells.', 'HePG2 cells were cultured in vitro with 0, 6, 12, or 24 g/ml TNT solution for 12, 24, and 48 h. Western blotting was performed to detect intracellular ERS-related proteins, including glucose-regulated protein (GRP) 78, GRP94, Caspase 4, p-Jun N-terminal kinase (JNK), and C/EBP homologous protein (CHOP). Real-time PCR was used to measure mRNA expression from the respective genes.', 'The expressions of ERS-related proteins GRP78 and GRP94 as well as mRNA and protein expression of ERS signaling apoptotic CHOP in the TNT treatment group were significantly increased. In addition, the mRNA and protein expression levels of ERS-induced apoptotic protein Caspase-4 were significantly increased. Flow cytometry revealed that after TNT treatment, the apoptosis rate also significantly increased.\Question: Does trinitrotoluene induce Endoplasmic Reticulum Stress and Apoptosis in HePG2 Cells?

SOLUTION: TNT could increase the expression levels of GRP78, GRP94, Caspase-4, and CHOP in HePG2 cells; this increase in protein expression might be involved in HePG2 apoptosis through the induction of the ERS pathway.

PROBLEM: Context: Cancer-associated fibroblasts (CAFs) are believed to play an essential role in cancer initiation and development. However, little research has been undertaken to evaluate the role of CAFs in endometrial cancer (EC) progression. We aim to detect the functional contributions of CAFs to promote progression of EC.', 'Stromal fibroblasts were isolated from endometrioid adenocarcinomas and normal endometrial tissues. The conditioned media of cultured CAFs and normal fibroblasts (NFs) were collected to detect the level of stromal cell-derived factor-1alpha (SDF-1), macrophage chemoattractant protein-1 (MCP-1), migration inhibitory factor (MIF), colony stimulating factor-1 (CSF-1), and interleukin-1 (IL-1) by ELISA. The CAFs or NFs were cocultured with EC cell lines to determine the proliferation, migration, and invasion by MTT assays and transwell chambers. Xenograft models were used to observe tumor growth. Matrix metalloproteinases (MMP)-2 and MMP-9 activity was evaluated by zymography. AMD3100 (a chemokine receptor 4 (CXCR4) antagonist) was used to block the SDF-1/CXCR4 axis. Neutralizing antibodies were used to detect PI3K/Akt and MAPK/Erk pathways by western blotting. SDF-1 and CXCR4 expressions were analyzed in xenotransplanted tumors and 348 cases by immunohistochemistry.', 'CAFs promoted proliferation, migration, and invasion as well as in vivo tumorigenesis of admixed EC cells significantly more than NFs by secreting SDF-1. These effects were significantly inhibited by AMD3100. CAFs promoted EC progression via the SDF-1/CXCR4 axis to activate the PI3K/Akt and MAPK/Erk signalings in a paracrine-dependent manner or increase MMP-2 and MMP-9 secretion in an autocrine-dependent manner. SDF-1 and CXCR4 expression upregulation accompanied clinical EC development and progression. High SDF-1 expression levels were associated with deep myometrial invasion, lymph node metastasis, and poor prognosis in EC.\Question: Do cancer-associated fibroblasts promote the progression of endometrial cancer via the SDF-1/CXCR4 axis?

SOLUTION:
Our data indicated that CAFs derived from EC tissues promoted EC progression via the SDF-1/CXCR4 axis in a paracrine- or autocrine-dependent manner. SDF-1 is a novel independent poor prognostic factor for EC patients' survival. Targeting the SDF-1/CXCR4 axis might provide a novel therapeutic strategy for EC treatment.