Tumor progression and metastasis

The initial observations relating CD44 expression to tumor dissemination were made in human non-Hodgkin s lymphomas by us and the group of Jalkanen (Pals et al., 1989 Horst et al., 1990 Koopman et al., 1993 Jalka-nen et al., 1990,1991). In these studies, expression of CD44 on human lym- 

Stage Grade Prognosis Normal Adenoma (n)d Carcinoma (n)d Metastases (i 

The major upregulation of CD44 occurs at the transition from normal mucosa to adenoma, indicating that deregulation of CD44 represents an early event in the adenoma-carcinoma sequence (Abbasi et al., 1993 Heider et al., 1993 Wielenga et al., 1993 Kim et al., 1994 P. A. Jackson et al., 1995 Got- 

Author N/RT/ISH- Exon6 Correlation withc Normal Expression iad 

Because CD44 splice variants containing v6 were shown to confer metastatic potential to rat carcinoma cell lines (Giinthert et al., 1991), overexpression of CD44 variants on colorectal carcinomas might also increase metastatic propensity, leading to disseminated disease and tumor-related death. To 

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Tumor-educated macrophages. (From Pollard, J.W., Tumor-educated macrophages promote tumor progression and metastasis, Nat. Rev. Cancer, 4, 71-74, 2004. Copyright year 2004, Macmillan Magazines Ltd and the author. Reproduced with permission from Macmillan.)... 

Albelda, S. M. (1993). Role of integrins and other cell adhesion molecules in tumor progression and metastasis. Lab. Invest. 68, 4-17. 

In breast cancer cells, increased numbers of chondroitin sulfate chains linked to P-selectin enhanced the attachment of cancer cells to vascular endothelial cells forcing tissue invasion of tumor cells (36). Increased levels of chondroitin sulfates were also found in melanoma (37) and ovarian carcinoma (38) and enhanced the mitogenic effect of platelet-derived growth factor-BB on fibrosarcoma cells (39). Chondroitin sulfates have a role in tissue remodeling, tumor progression, and metastasis (40). 

Tumor hypoxia results from a disparity between the demand and the supply of oxygen to the tumor tissue this consequence occurs when tumor cells are too distant from the vascular supply. By overcoming the hostile hypoxic environment, a tumor induces a new vascular supply to provide oxygen and nutrition - a process called angiogenesis. Accumulated evidences indicate that tumor hypoxia plays an important role in tumor progression and metastasis [5-8]. Studies both in vitro and in vivo demonstrated that hypoxic exposure of... 

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