[gdpawel]

Some patients' tumors respond to chemotherapy and some do not. A pathway/mechanism - cancer stem cells - may be the cause. To prevent cancer's return may require one therapy to shrink a tumor and another therapy to kill the abnormal seeds that sprouted it. Conventional cancer therapies have been good at shrinking tumors, but the ability to shrink tumors has little or no correlation to survival times. Newer treatments need to decrease the number of cancer stem cells.

There is a communication between stem cells and a tumor. It sends out a signal that make the different cells of the tumor and the cancer cells then (send chemical messages) that cycle back to the cancer stem cell. Every tissue and organ in the body is made of cells. In order for cells to grow, divide, or die, they send and receive chemical messages. These messages are transmitted along specific pathways that involve various genes and proteins in a cell.

Finding the protein that prevents cancer from metastasizing, isolating factors within the stem cell microenvironment, can influence tumor cell fate and reverse the cancerous properties of metastatic tumor cells. However, it is not the only tumor suppressive factor within the stem cell microenvironment. Not all genes and proteins have a critical role in the survival and growth of cancer cells.

In some cases, targeted drugs may kill tumor cells without killing microvascular cells in the same time frame. In other cases, they may kill microvascular cells without killing tumor cells. Yet in other cases, they could kill both types of cells or neither type of cells. The ability to these targeted agents to kill tumor and/or microvascular cells in the same tumor is highly variable among the different agents.

You still need to measure the net result of all cellular processes, including interactions, occurring in real time when cancer cells actually are exposed to specific cancer drugs, not just the individual molecular targets. Improving cancer patient diagnosis and treatment through a combination of cellular and gene-based testing will offer predictive insight into the nature of an individual's particular cancer and enable oncologists to prescribe treatment more in keeping with the heterogeneity of the disease.

Sources:
Cell Function Analysis
European Science Foundation
American Association for Cancer Research