Inhibition of vimentin or β1 integrin reverts morphology of prostate tumor cells grown in laminin-rich extracellular matrix gels and reduces tumor growth in vivo

Abstract

Prostate epithelial cells grown embedded in laminin-rich extracellular matrix (lrECM) undergo morphologic changes that closely resemble their architecture in vivo. In this study, growth characteristics of three human prostate epithelial sublines derived from the same cellular lineage, but displaying different tumorigenic and metastatic properties in vivo, were assessed in three-dimensional lrECM gels. M12, a highly tumorigenic and metastatic subline, was derived from the immortalized, prostate epithelial P69 cell line by selection in athymic, nude mice and found to contain a deletion of 19p-q13.1. The stable reintroduction of an intact human chromosome 19 into M12 resulted in a poorly tumorigenic subline, designated F6. When embedded in lrECM gels, the parental, nontumorigenic P69 line produced acini with clearly defined lumena. Immunostaining with antibodies to B-catenin, E-cadherin, or A 6 and B 1 integrins showed polarization typical of glandular epithelium. In contrast, the metastatic M12 subline produced highly disorganized cells with no evidence of polarization. The F6 subline reverted to acini-like structures exhibiting basal polarity marked with integrins. Reducing either vimentin levels via small interfering RNA interference or the expression of A 6 and B 1 integrins by the addition of blocking antibodies, reorganized the M12 subline into forming polarized acini. The loss of vimentin significantly reduced M12-Vim tumor growth when assessed by s.c. injection in athymic mice. Thus, tumorigenicity in vivo correlated with disorganized growth in three-dimensional lrECM gels. These studies suggest that the levels of vimentin and B 1 integrin play a key role in the homeostasis of the normal acinus in prostate and that their dysregulation may lead to tumorigenesis. [Mol Cancer Ther 2009;8(3):499 -508]

DNA strand breaks and hypoxia response inhibition mediate the radiosensitisation effect of nitric oxide donors on prostate cancer under varying oxygen conditions

“…All treatments resulted in failure of the cells to generate acinar structures with mature lumens (data not shown). This evidence strongly suggests that the main effects observed are anti-proliferative and therefore will result in lower tumourigenicity in vivo [16,19,20]. Furthermore, these 3D culture results agree with the results from 2D culture.…”

“…However, in an attempt to mimic the in vivo situation, an in vitro 3D model has been utilised, which has previously been shown to behave similarly to a mouse xenograft model [20]. It is not possible to mimic the chaotic, oxygenation of a solid tumour deposit in the in vitro setting.…”

In Vitro Modeling of Tissue-Specific 3D Microenvironments and Possibile Application to Pediatric Cancer Research

“…This tumor-derived matrix has the characteristics of a basement membrane-like matrix, since it is mainly composed of type IV collagen, laminin, perlecan, nidogen/entactin and trophic factors [110,111]. It was shown to sustain 3D cultures of breast-, colon-, prostate-, and lung-derived tumor cells, allow expression of some of their original tissuespecific functions and to allow co-culturing, thus confirming, for example, that, in an in vitro prostate tumor model, stromal cells might activate tumor growth and invasion's process [74,79,[112][113][114]. However, this extractive matrix, besides being variable in quality from batch to batch, fails, at least in part, in recreating the native mechanics of normal basement membrane, and does not correspond at all to the other matrices found within connective tissues and parenchyma.…”

Pyruvate uptake is increased in highly invasive ovarian cancer cells under anoikis conditions for anaplerosis, mitochondrial function, and migration

“…The three-dimensional culture approach has been used by other researchers to study cancer cells due to its closeness to in vivo tumor morphology (4,7,41). Matrigel culture of mammary epithelial cancer cells has been utilized to study lack of luminal clearance and luminal filling that takes place in mammary cancer and the oncogenes that play a role in this observation (7).…”