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Cancer progression is a multistep process during which normal cells exhibit molecular changes that culminate into the highly malignant and metastatic phenotype, observed in cancerous tissues. The initiation of cell transformation is generally associated with genetic alterations in normal cells that lead to the loss of intercellular- and/or extracellular-matrix- (ECM-) mediated cell adhesion. Transformed cells undergo rapid multiplication and generate more modifications in adhesion and motilityrelated molecules which allow them to escape from the original site and acquire invasive characteristics. Integrins, which are multifunctional adhesion receptors, and are present, on normal as well as transformed cells, assist the cells undergoing tumor progression in creating the appropriate environment for their survival, growth, and invasion. In this paper, we have briefly discussed the role of ECM proteins and integrins during cancer progression and described some unique conditions where adhesion-related changes could induce genetic mutations in anchorage-independent tumor model systems [ABSTRACT FROM AUTHOR]

Background: Anchorage independent growth is an important hallmark of oncogenic transformation. Previous studies have shown that when adhesion dependent fibroblasts were prevented from adhering to a substrate they underwent anoikis. In the present study we have demonstrated how anoikis resistant cells gain the transformation related properties with sequential selection of genes. We have proposed this process as a model system for selection of transformed cells from normal cells. Results: This report demonstrates that some fibroblasts can survive during late stages of anoikis, at which time they exhibit transformation-associated properties such as in vitro colony formation in soft agar and in vivo subcutaneous tumour formation in nude mice. Cytogenetic characterisation of these cells revealed that they contained a t (2; 2) derivative chromosome and they have a selective survival advantage in non adherent conditions. Gene expression profile indicated that these cells over expressed genes related to hypoxia, glycolysis and tumor suppression/metastasis which could be helpful in their retaining a transformed phenotype. Conclusion: Our results reveal some new links between anoikis and cell transformation and they provide a reproducible model system which can potentially be useful to study multistage cancer and to identify new targets for drug development. [ABSTRACT FROM AUTHOR]

Hypoxia is a condition of insufficient tissue oxygenation, which is observed during normal development as well as tumorigenesis and its response at the cellular level is primarily mediated through hypoxia inducible factors (HIFs). HIFs have a significant role in the maintenance of stemness in both stem cells as well as in cancer stem cells (CSC) by acting as transcription factors. The CSCs are proposed to be the driving force of colon tumorigenesis and malignancy. These HIFs play a significant role in a wide range of diseases including colon cancer. HIF’s signaling functions with stemness, and maintaining Wnt/β-catenin signaling pathways. Due to HIFs functional significance in stemness maintenance in malignancy, targeting HIFs might provide a new approach for development of new therapy for colon cancer. In this review, we will be briefing on the colon and its stem cells, various molecular signaling pathways involved in stemness preservation, and the role hypoxia and its HIFs in the maintenance of stemness in colon stem cells and colon cancer stem cells. [ABSTRACT FROM AUTHOR]