Is Wnt a tumor suppressor?

Is Wnt a tumor suppressor?

These studies are consistent with the Wnt pathway acting as a tumor suppressor in retinoblastoma and suggest that loss of Wnt signaling is tumorigenic in the retina.

Is Wnt signaling autocrine?

These results provide strong evidence, independent of the use of Wnt antagonists, that constitutive Wnt signaling was due to an autocrine loop in these human tumor cells, and implicated LRP6 as the specific Wnt canonical receptor involved.

How do you stimulate Wnt signaling?

To activate Wnt signaling, one can add Wnt protein, either in a purified form or as conditioned medium to cells. Cells producing active Wnt can be obtained from the ATCC (see also the reagents page). Active Wnt protein can be obtained from several companies.

What is Juxtacrine communication?

In biology, juxtacrine signalling (or contact-dependent signalling) is a type of cell–cell or cell–extracellular matrix signalling in multicellular organisms that requires close contact. A communicating junction links the intracellular compartments of two adjacent cells, allowing transit of relatively small molecules.

What are paracrine secretions?

Paracrine signaling is a form of cell signaling, a type of cellular communication in which a cell produces a signal to induce changes in nearby cells, altering the behaviour of those cells. Cells that produce paracrine factors secrete them into the immediate extracellular environment.

Does Wnt stabilize beta catenin?

Wnts also stabilize β-catenin via inhibition of GSK-3β, but, in contrast to hypertrophic signaling, this is not believed to involve PKB-induced Ser-9 phosphorylation (16, 32).

Is Wnt a growth factor?

The Wnt family of secreted growth factors plays key roles in directing cell patterning both during development and in adult tissues. In this pathway, Wnts activate β-catenin signalling and consequently modulate the expression of specific target genes that regulate cell proliferation, apoptosis, and cell fate [1,2].

What does the AXIN2 gene do in cancer?

The AXIN2 gene has been mapped to 17q23-q24, a region that shows frequent loss of heterozygosity in breast cancer, neuroblastoma, and other tumors. Mutations in this gene have been associated with colorectal cancer with defective mismatch repair. [provided by RefSeq, Jul 2008]

What is the function of AXIN2 in Wnt?

The Axin-related protein, Axin2, presumably plays an important role in the regulation of the stability of beta-catenin in the Wnt signaling pathway, like its rodent homologs, mouse conductin/rat axil.

Does Wnt3a affect β-catenin activity in SW620 cells?

By contrast, in APC-defective SW620 cells, constitutive levels of β-catenin, Axin2, or TOPflash activity are maximally activated and unaffected by Wnt3a ( Fig. 1 A and B ).

Is wingless-type MMTV signaling pathognomonic in colorectal cancer?

Aberrant activation of canonical Wingless-type MMTV integration site family (Wnt) signaling is pathognomonic of colorectal cancers (CRC) harboring functional mutations in either adenomatous polyposis coli or β-catenin.