The characteristics of cancer cells

Cancer tissue has a very distinctive morphological features when observed with a microscope. Among a large number of natural cell mitosis, variations in the number and size of the nucleus, variations in size and shape of cells, there were no distinctive features of cellular, mobile coordination does not occur commonly seen in normal tissue and there is no clear boundary network.

Immunohistochemistry and other molecular methods used to find the morphological characteristics typical of cancer cells / tumors, as the referral diagnosis and prognosis.

Hahn and colleagues used an ectopic expression of telomerase reverse-transcriptase combination with h-ras oncogene and SV40 T antigen of the virus to induce the conversion tumorigenik on fibroblast cells and human epithelial cells, which occurs due to disruption of intracellular metabolic path. Phenotype characteristic of cancer cells after undergoing a transformation from normal cells, among others:

Transformation in vitro

* There was cytological changes such as in cancer cells in vivo, such as increased cytoplasmic basofilia, increasing the number and size of the nuclei
* Changes in cell growth characteristics:

@. difficult to have undergone differentiation to death despite repeated
@. grow that will not stop running, although it has been squeezed by the surrounding cells, so that cancer tissue has a high density
@. serum and growth factors requires fewer
@. no longer needs to reproduce the interface layer, and can grow as colonies free in the semi-solid medium.
@. has no control over the cell cycle
@. difficult to undergo apoptosis

* Changes in the structure and function of cell membranes, including the increase due to lectin herbal aglutinabilitas
* Changes in the composition of the interface cell, glycoproteins, proteoglycans, glikolipid and mucin, tumorik antigen expression and increased absorption of amino acids and nucleosides heksos.
* No interaction matrix cells and cell-extracellular, so there is no decrease in the rate of differentiation
* Cancer cells do not respond to stimulation of substances that induce differentiation, because the interface changes the composition of cells, including the molecular composition of substances pencerap concerned.
* Changes in cellular signal transduction mechanisms, including the trajectories are very fundamental, in addition to regulations that control the trajectory pencerap function of growth factors, levels of phosphorylation and defosforilasi.
* The ability to induce tumors in the model. This capability is a sine qua non which defines the word "malignant" in transformation in vitro. However, cancer cells that do not have this ability, still has character "tumorigenik" on other models.

Transformation in vivo

* Increased expression of oncogene protein as a result of translocations, amplification and mutation of chromosomes.
* There was no protein expression of the gene "tumor suppressor".
* Changes in DNA methylation.
* There is a transcription of the genetic disorders that cause overproduction of growth supporting substances, such as IGF-2, TGF-α, tumor angiogenesis factor, PDGF, and hematopoietic growth factors such as CSF and interleukin.
* There was no genetic balance, which becomes increasingly uncontrolled proliferation, increased the likelihood of metastasis.
* Changes in enzyme patterns and increased enzymes that play a role in the synthesis of nucleic acids and enzymes that are lytic, such as protease, collagenase and glycosidase.
* Production onkofetal antigens, such antigens plasentis karsinoembrionik and hormones (eg, chorionic gonadotropin), or such Isozyme alkalina plasentis phosphatase.
* The ability to avoid the host antitumor response.