Disease relevance of HAS3

• To evaluate the physiological role of human HAS3, expression vectors for this protein were transfected into TSU cells (a prostate cancer cell line), and the phenotypic changes in these cells were examined [1].
• In our study, colon carcinoma cells isolated from a lymph node metastasis (SW620) produced more pericellular HA and expressed higher levels of HAS3 mRNA compared to cells isolated from a primary colon carcinoma (SW480) [2].
• Human mesothelial cells, which synthesize large amounts of hyaluronan, express mRNAs encoding all three HAS isoforms, whereas their transformed counterparts, mesothelioma cells, which produce only minute amounts of hyaluronan, express only HAS3 mRNA [3].
• Human lung fibroblasts and the glioma cell line U-118 MG express only the HAS2 and HAS3 genes [3].
• Of 20 cases of pulmonary adenocarcinoma, 5 overexpressed HAS1 (25%), 16 of 20 HAS2 (80%), and 4 of 20 HAS3 (20%) [4].

High impact information on HAS3

• These results suggested that the HAS3-induced overexpression of hyaluronan enhanced tumor cell growth, extracellular matrix deposition, and angiogenesis but was not sufficient to induce metastatic behavior in TSU cells [1].
• Hyaluronan synthase 3 overexpression promotes the growth of TSU prostate cancer cells [1].
• Aggressive cells in prostate cancer secrete extracellular hyaluronan (HA) as a result of up-regulated HA synthase enzymes HAS2 and HAS3 [5].
• The microvilli induced by HAS3 were gradually withered by introduction of an inhibitor of hyaluronan synthesis and rapidly retracted by hyaluronidase digestion, whereas they were not affected by competition with hyaluronan oligosaccharides and disruption of the CD44 gene, suggesting independence of hyaluronan receptors [6].
• In cells transfected with green fluorescent protein (GFP)-tagged Has3, the dorsal surface was decorated by up to 150 slender, 3-20-microm-long microvillus-type plasma membrane protrusions, which also contained filamentous actin, the hyaluronan receptor CD44, and lipid raft microdomains [6].

Biological context of HAS3

• These findings suggest that HAS3 gene expression plays a crucial role in the regulation of hyaluronan synthesis in the epidermis [7].
• To assess functionality, HAS3 expression in SW620 cells was inhibited by transfection with an asHAS3 construct [2].
• Partial clones facilitated the isolation of genomic and cDNA clones representing the mouse Has3 open reading frame [8].
• HAS3 was localized to human chromosome 16q22.1 and Has3 to mouse Chr 8 [9].
• Stimulation of mesothelial cells with platelet-derived growth factor-BB induced an up-regulation of mRNA for HAS2 to a maximum after 6 h of stimulation; HAS1 and HAS3 genes were only induced slightly [3].

Anatomical context of HAS3

• Furthermore, in situ mRNA hybridization showed that mouse epidermal keratinocytes abundantly expressed HAS3 mRNA from the basal to the granular cell layers, suggesting that HAS3 functions in epidermis [7].
• Labour-like cyclic mechanical stretch for 24, 36 and 48 h significantly enhanced the secretion of HA, from cultured human uterine cervical fibroblast (CxF) cells, 128.7, 151.4 and 173.2%, respectively, concomitant with a significant augmentation of HAS1 (36, 48 h), HAS2 (24, 36 and 48 h) and HAS3 (48 h) mRNA expression [10].
• Expression of the mouse Has3 open reading frame in transfected COS-1 cells led to high levels of hyaluronan synthesis, as determined through a classical particle exclusion assay, and by in vitro HA synthase assays [8].
• MAbs to beta 1 (DH12) and alpha 2 (HAS3) showed positive membrane and cytoplasmic staining of basal cells and luminal epithelial cells [11].
• Furthermore, we suggest that overexpression of HAS1 and its variants in combination with HAS3 may form an HA matrix around WM cells, thus preventing their elimination by the immune system, and it promotes their migration and may facilitate the spread of disease [12].

Associations of HAS3 with chemical compounds

• Transforming growth factor-beta1 reduced HAS2 mRNA slightly, and hydrocortisone reduced it strongly, within 6 h of stimulation in mesothelial cell cultures but did not significantly affect the expression of mRNAs for HAS1 and HAS3 [3].
• Moreover, cell proliferation and invasion were inhibited by suppressing the activity of HAS3 expressed in LM8 cells, using hyaluronan synthase suppressor, 4-methylumbelliferone (MU) [13].
• HAS2 and HAS3 mRNAs were also expressed by bovine chondrocytes isolated from either the superficial or deep zone of articular cartilage, and by human chondrocytes cultured either in the absence or presence of IL-1 and retinoic acid [14].
• Moreover, beta-carotene, a provitamin A, influenced HA production and HAS3 gene expression in a manner similar to the retinoids [15].
• We observed that RA and retinol markedly induced the expression of HA synthase-3 (HAS3) mRNA [15].

Regulatory relationships of HAS3

• In contrast to the activatory effect on HAS1, TGF-beta dose-dependently suppresses HAS3 mRNA [16].
• HAS1 mRNA was upregulated by transforming growth factor-beta and HAS3 mRNA was upregulated by interleukin-1beta and somewhat by tumor necrosis factor-alpha in the RA cells [17].
• In addition, at 24 h mRNA for HA synthase 2 was expressed in all samples whereas mRNA for HA synthase 3 was only expressed in strained cells [18].

Other interactions of HAS3

• Isolation of a genomic fragment of human HAS3 indicated high conservation between mouse and human sequences, similar to those observed for HAS1 and HAS2 [8].
• HA and its biosynthetic enzymes (HAS1, HAS2 and HAS3) are thought to participate in tumor growth and cancer progression [2].
• Expression of HAS3 mRNA was increased by about 14- and 10-fold after 3-h stimulation with 10 ng/ml TNF-alpha and 1 ng/ml IL-1beta, respectively [19].
• The gene expressions in adhesive subacromial bursae were approximately threefold to fourfold greater than those in nonadhesive bursae for the genes for Type I and Type III procollagens, CD34 antigen in vascular endothelium, hyaluronan synthase-3, and interferon-gamma [20].
• We found that HA of molecular weight which HAS3 produces enhanced biological functions related to metastasis such as cell proliferation, invasion, and degradation of extracellular matrix [13].

Analytical, diagnostic and therapeutic context of HAS3

• HAS3 messenger ribonucleic acid (mRNA) was also detectable in all these strains by RT-PCR under both control and IL-1beta-treated conditions [21].
• In the 23 patients that received chemotherapy, the expression of HAS1, HAS2 and HAS3 was unrelated to the chemotherapy response [22].
• In addition, activation patterns of mitogen activated protein kinases (MAPK) were analyzed by Western blot experiments. mRNA for HAS1 is undetectable but HAS3 mRNA can be readily detected in freshly isolated CD133+ as well as in CD133- UCB cells [23].
• RT-PCR analysis and in situ hybridization revealed that the mRNA of HAS2 was highly expressed in the synovial membrane and articular cartilage, whereas the expression of HAS3 mRNA was slightest in these tissues [24].
• Real-time PCR analysis demonstrated a 13-fold decrease in hyaluronan synthase 3 expression in mineralising MG63 cells; no significant change in hyaluronan synthase 2 expression in mineralising cells and hyaluronan synthase 1 was not expressed [25].

References