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.

[EX Q]: Context: Exosomes are 30-100 nm membrane vesicles of endocytic origin, mediating diverse biological functions including tumor cell invasion, cell-cell communication and antigen presentation through transfer of proteins, mRNAs and microRNAs. Recent evidence suggests that microRNAs can be released through ceramide-dependent secretory machinery regulated by neutral sphingomyelinase 2 (nSMase2) enzyme encoded by the smpd3 gene that triggers exosome secretion. However, whether exosome-mediated microRNA transfer plays any role in cell invasion remains poorly understood. Thus, the aim of this study was to identify the exosomal microRNAs involved in breast cancer invasion.', 'The expression level of endogenous and exosomal miRNAs were examined by real time PCR and the expression level of target proteins were detected by western blot. Scanning electron and confocal microscopy were used to characterize exosomes and to study its uptake and transfer. Luciferase reporter plasmids and its mutant were used to confirm direct targeting. Furthermore, the functional significance of exosomal miR-10b was estimated by invasion assay.', 'In this study, we demonstrate that microRNA carrying exosomes can be transferred among different cell lines through direct uptake. miR-10b is highly expressed in metastatic breast cancer MDA-MB-231 cells as compared to non-metastatic breast cancer cells or non-malignant breast cells; it is actively secreted into medium via exosomes. In particular, nSMase2 or ceramide promotes the exosome-mediated miR-10b secretion whereas ceramide inhibitor suppresses this secretion. Moreover, upon uptake, miR-10b can suppress the protein level of its target genes such as HOXD10 and KLF4, indicating its functional significance. Finally, treatment with exosomes derived from MDA-MB-231 cells could induce the invasion ability of non-malignant HMLE cells.\Question: Does exosome-mediated transfer of miR-10b promote cell invasion in breast cancer?
[EX A]: Together, our results suggest that a set of specific microRNAs may play an important role in modulating tumor microenvironment through exosomes. Thus, a better understanding of this process may aid in the development of novel therapeutic agents.

[EX Q]: Context: To assess, in a retrospective cohort, urinary tract urothelial carcinoma (UT-UC) in patients with various stages of chronic kidney disease (CKD) and their clinicopathological features, as patients with end-stage renal disease (ESRD) have a higher incidence of UT-UC, but the relationship between early stages of CKD and characteristics of UT-UC are less well known.', 'The study included 267 patients with pathologically confirmed UT-UC from January 1994 to December 2006; all had a physical examination (blood pressure), and measurements of laboratory data (serum creatinine, serum haemoglobin) and pathological data. The glomerular filtration rate (GFR) was calculated using the Modification of Diet in Renal Disease equation. Patients were divided into three groups by individual GFR (mL/min), i.e. >60 (no/mild CKD), 30-60 (CKD stage 3) and <30 (CKD stage 4/5).', 'The CKD stages included 81 (30.3%) patients with none/mild CKD, 121 (45.3%) with CKD stage 3 and 65 (24.3%) with CKD stage 4/5. There was a significant and parallel increase in the frequency of UT-UC as CKD severity increased from none/mild CKD to stage 3 (11% vs 55%), and from CKD stage 3 to 4/5 (55% vs 71%; P < 0.05). Pathologically, the frequency of high-grade and high T stage UT-UC in patients with CKD stage 3 (90% and 35%, respectively) and CKD stage 4/5 (91% and 29%, respectively) were significantly greater than in the group with none/mild CKD (P < 0.001). Advanced age and more distant metastasis were independent risk factors for patient survival.\Question: Does the aggressiveness of urinary tract urothelial carcinoma increase with the severity of chronic kidney disease?
[EX A]: The aggressiveness of UT-UC increased with the severity of CKD, and this might have important clinical consequences.

[EX Q]: Context: Matrix metalloproteinases (MMPs) play pivotal roles in tumor progression. MMP-13 (collagenase-3) digests collagen and other extracellular components.', 'Reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry and zymograph were used to study the roles of MMP-13 during the neoplastic process of oral squamous cell carcinoma (OSCC).', 'Increase of MMP-13 mRNA and protein expression in OSCC cell lines relative to cultivated normal oral keratinocytes was found. MMP-13 mRNA expression in OSCC was significantly higher than in non-cancerous match tissue (NCMT) in 36 tissue pairs. Esophageal squamous cell carcinoma also exhibited high MMP-13 mRNA expression. The percentage of OSCC exhibiting strong MMP-13 immunoreactivity was significantly higher than pre-invasive lesion and NCMT. Treatment with >5 microm epigallocatechin-3-gallate (EGCG) to OEC-M1 cells suppressed the expression and activity of MMP-13.\Question: Do increase of MMP-13 expression in multi-stage oral carcinogenesis and epigallocatechin-3-gallate suppress MMP-13 expression?
[EX A]:
MMP-13 could be a potential tumor marker for OSCC. The effects of EGCG in tumor inhibition may act partially through the modulation of MMP-13.