Disease relevance of LUM

• The small leucine-rich proteoglycan lumican inhibits melanoma progression [1].
• Interestingly, TGFbeta1 and conditioned medium derived from pancreatic cancer cell lines synergistically suppressed the expression of known anti-tumor factors decorin and lumican, but stimulated the expression of pro-metastatic factor versican in cultured PSCs [2].
• The mRNA levels for lumican and decorin were increased in the joint capsules of the contracture knees in all groups when compared to normal capsules [3].
• Further evidence of altered lumican expression in breast cancer was manifested by discordance between lumican mRNA and protein localization in some regions of tumours but not in adjacent morphologically normal tissues [4].
• EXPERIMENTAL DESIGN: Lumican and decorin expression was examined in a cohort of 140 invasive breast carcinomas by Western blot analysis [5].

Psychiatry related information on LUM

• The PRICOR project, sponsored by the United States Agency for International Development, has designed and implemented methods for quality assessment and problem solving in LDC health systems [6].

High impact information on LUM

• The thickness and density of tenascin, lumican, and procollagen III in the reticular basement membrane (RBM) were quantified immunohistochemically by confocal microscopy [7].
• Treating asthmatics with anti-IL-5 antibody, which specifically decreased airway eosinophil numbers, significantly reduced the expression of tenascin, lumican, and procollagen III in the bronchial mucosal RBM when compared with placebo [7].
• Furthermore, expression of known tumor progression genes identified in the screen (IL-6 and cysteine-rich angiogenic inducer 61) as well as potential regulators (lumican and F-box-only 6) follow similar patterns in patient glioma [8].
• The small leucine-rich proteoglycan lumican was identified from a human placenta cDNA library by the expression cloning method as a gene product that interacts with membrane-type matrix metalloproteinase-1 (MT1-MMP) [9].
• The expression levels of p21 in HT1080/Lum were proportional to the concentration of secreted lumican and showed reverse corelation with colony formation in soft agar [9].

Chemical compound and disease context of LUM

• The lumican in colorectal cancer cells had non-sulfated or poorly sulfated polylactosamine side chains [10].
• In this study, the expression of lumican was studied in two human melanoma cell lines (WM9, M5) as well as in normal neonatal human melanocytes (HEMN) using real time PCR, western blotting with antibodies against the protein core and keratan sulfate, and treatments with specific enzymes [11].

Biological context of LUM

• Lumican induced and/or increased the apoptosis of B16F1 cells [1].
• For that purpose, B16F1 mouse melanoma cells were stably transfected with an expression plasmid containing the complete lumican cDNA [1].
• Lumican expression by tumor cells did not change the proliferative activity of mouse melanoma cells in monolayer culture and did not influence either cell adhesion to extracellular matrix gel or type I collagen or cell spreading on these substrates [1].
• Lumican with polylactosamine (nonsulfated keratan sulfate) side chains was detected in extracts of corneas as early as day 7 of embryonic development, and continued to accumulate within the cornea through day 18 [12].
• Treatment of lumican with chondroitinase ABC, keratanase-I and -II, and/or endo-beta-galactosidase was used to determine the degree of glycosylation of the lumican core protein [13].

Anatomical context of LUM

• Stable expression of lumican in HeLa cells induced expression of p21 and reduction of colony formation in soft agar, which were both abolished by the expression of MT1-MMP [9].
• To evaluate the expression of lumican and decorin, the major proteoglycans of the adult corneal stroma, during the acquisition of corneal transparency in developing chick embryos [12].
• RESULTS: Lumican was present in the human sclera as a 70- to 80-kDa core protein with short unsulfated lactosaminoglycan side chains [13].
• PURPOSE: Lumican is a keratan sulfate proteoglycan originally identified in cornea, but present in a variety of connective tissues where it presumably regulates collagen fibril formation and organization [13].
• In contrast, reporter assays carried out in human fetal lung fibroblasts, where lumican expression is deplete, revealed the presence of a repressor element located between 384 and 598 bp upstream of the transcription start site [14].

Associations of LUM with chemical compounds

• Lumican protein from bovine cornea and recombinant lumican core protein fused to glutathione S-transferase was shown to be cleaved at multiple sites by recombinant MT1-MMP [9].
• In the adult cartilage lumican exists predominantly in a glycoprotein form lacking keratan sulfate, whereas the juvenile form of the molecule is a proteoglycan [15].
• Decorin and lumican were extracted from bovine corneal stroma with either 0.7 M NaCl or 4 M guanidine HCl and purified by DEAE and Sepharose CL-4B chromatography [16].
• Histological composition was assessed in sections stained with haematoxylin and eosin, and the expression of lumican and decorin was assessed by immunohistochemistry; both were quantified by semi-quantitative scoring [17].
• Non-intrusive, non-contacting frequency-domain photothermal radiometry (FD-PTR or PTR) and frequency-domain luminescence (FD-LUM or LUM) have been used with 659- and 830-nm laser sources to assess the pits and fissures on the occlusal surfaces of human teeth [18].

Other interactions of LUM

• Cleavage of lumican by membrane-type matrix metalloproteinase-1 abrogates this proteoglycan-mediated suppression of tumor cell colony formation in soft agar [9].
• Furthermore, the degree of PG immunoreactivity was significantly correlated with airway responsiveness in the asthmatics (lumican; r = -0.77, p < 0.05; biglycan: r = -0.76, p < 0.05; versican: r = -0.74, p = 0.06) [19].
• The results of these studies suggest that decorin and lumican expression are independently regulated during the period of acquisition of corneal transparency [12].
• Further characterization of the >200-kDa lumican-immunopurified complex indicated that aggrecan (the cartilage proteoglycan) was covalently associated with lumican [13].
• CONCLUSIONS: Reducible and nonreducible lumican-aggrecan interactions occur in the scleral extracellular matrix and result in the formation of high-molecular-weight complexes that increase with age [13].

Analytical, diagnostic and therapeutic context of LUM

• After subcutaneous injections of transfected B16F1 cells in syngenic mice, lumican expression significantly decreased subcutaneous tumor formation in vivo, with a concomitant decrease of cyclin D1 expression [1].
• In addition, on Western blots, a larger >200-kDa species was apparent that was immunologically related to lumican [13].
• METHODS: Western blot analyses, immunohistochemistry, and immunoaffinity chromatography were used to detect and purify the lumican core protein from tissue extracts from human donors 6 to 89 years of age [13].
• Lumican down-regulation by endoglin appeared to be controlled, at least in part, at the transcriptional level, as indicated by RT-PCR, and transient transfection experiments using a lumican promoter reporter based vector [20].
• The gene (LUM) was localized to human chromosome 12 by hybridizing a cDNA probe to a Southern blot containing a human/hamster monochromosomal mapping panel DNA [21].

References