The most important factor for predicting lymph-node metastasis in early esophageal cancer is the presence of submucosal infiltration. Early adenocarcinomas and SCCs do not differ with regard to their rate of lymphatic involvement. The rate of lymph-node metastasis increases with the depth of submucosal infiltration, but metastases can already occur in sm1 lesions. Submucosal infiltration is a contraindication for endoscopic mucosectomy. Limited surgical procedures without adequate lymphadenectomy do not appear to be appropriate in the treatment of patients with submucosal esophageal carcinomas.
UVA irradiation leads to photoaging including clinical features such as wrinkle formation, reduced recoil capacity and blister formation of the skin. Besides synthesis of the extracellular matrix, its regulated degradation by various matrix-metalloproteinases (MMPs) determines the amount and the composition of the extracellular matrix within the dermis and the basement membrane of the dermo-epidermal junction. In this study we therefore ascertained whether UV irradiation could modulate the synthesis of MMPs with substrate specificities for dermal (collagen I, III, V) and basement membrane compounds (collagen IV, VII, proteoglycans, laminin) and whether synthesis of the counteracting tissue inhibitor of metalloproteinases (TIMP-1) was also affected. Following UVA irradiation specific mRNAs of MMPs 1, 2 and 3 were induced concomitantly up to 5-fold compared to mock irradiated controls. In contrast, TIMP-1 mRNA levels remained unaltered. Immunoprecipitation indicated that after UVA irradiation synthesis and secretion of MMPs 1, 2 and 3 into the supernatant increased. Taken together, our data show that UVA irradiation coordinately induced MMPs 1, 2 and 3 implying similar mechanisms in their regulatory pathways, while TIMP-1 synthesis was not altered. Hence, unbalanced synthesis of MMPs potentially contributes to the dissolution of dermal and basement membrane compounds finally leading to blister formation and cutaneous photoaging.
Measuring PDGFA, bFGF, and HIF1a expression may contribute to a better understanding of the prognosis of patients with pancreatic cancer and may even play a crucial role for the distribution of patients to multimodal therapeutic regimens. Larger studies including patients treated with actual chemotherapeutics seem to be warranted.
BackgroundOesophageal cancer is a highly aggressive tumour entity with at present poor prognosis. Therefore, novel treatment options are urgently needed. Hyaluronan (HA) is a polysaccharide present in the matrix of human oesophageal squamous cell carcinoma (ESCC). Importantly, in vitro ESCC cells critically depend on HA synthesis to maintain the proliferative phenotype. The aim of the present study is (1) to study HA-synthase (HAS) expression and regulation in human ESCC, and (2) to translate the in vitro results into a mouse xenograft model of human ESCC to study the effects of systemic versus tumour targeted HAS inhibition on proliferation and distribution of tumour-bound and stromal hyaluronan.MethodsmRNA expression was investigated in human ESCC biopsies by semiquantitative real-time RT PCR. Furthermore, human ESCC were xenografted into NMRI nu/nu mice. The effects on tumour progression and morphology of 4-methylumbelliferone (4-MU), an inhibitor of HA-synthesis, and of lentiviral knock down of HA-synthase 3 (HAS3), the main HAS isoform in the human ESCC tissues and the human ESCC cell line used in this study, were determined. Tumour progression was monitored by calliper measurements and by flat-panel detector volume computed tomography (fpVCT). HA content, cellular composition and proliferation (Ki67) were determined histologically.ResultsmRNA of HAS isoform 3 (HAS3) was upregulated in human ESCC biopsies and HAS3 mRNA was positively correlated to expression of the epidermal growth factor (EGF) receptor. EGF was also proven to be a strong inductor of HAS3 mRNA expression in vitro. During the course of seven weeks, 4-MU inhibited progression of xenograft tumours. Interestingly, remodelling of the tumour into a more differentiated phenotype and inhibition of cell proliferation were observed. Lentiviral knockdown of HAS3 in human ESCC cells prior to xenografting mimicked all effects of 4-MU treatment suggesting that hyaluronan produced by ESCC is accountable for major changes in tumour environment in vivo.ConclusionsSystemic inhibition of HA-synthesis and knockdown of tumour cell HAS3 cause decreased ESCC progression accompanied by tumour stroma remodelling and may therefore be used in novel approaches to ESCC therapy.
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