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Cancer research ranges from epidemiology, molecular bioscience to the performance of clinical trials to evaluate and compare applications of the various cancer treatment. These applications include surgery, radiation therapy, chemotherapy, hormone therapy, Immunotherapy and combined treatment modalities such as chemo-radiotherapy. Starting in the mid-1990s, the emphasis in clinical cancer research shifted towards therapies derived from biotechnology research, such as immunotherapy and gene therapy.
This type of research involves many different disciplines including genetics, diet, environmental factors (i.e. chemical carcinogens). In regard to investigation of causes and potential targets for therapy, the route used starts with data obtained from clinical observations, enters basic research, and, once convincing and independently confirmed results are obtained, proceeds with clinical research, involving appropriately designed trials on consenting human subjects, with aim to test safety and efficiency of the therapeutic intervention method. Important part of basic research is characterization of the potential function of mechanisms of carcinogenesis, in regard to the types of genetic and epigenetic changes that are associated with cancer development. The mouse is often used as a mammalian model for manipulation of the function of genes that play a role in tumor formation, while basic aspects of tumor initiation, such as mutagenesis, are assayed on cultures of bacteria and mammalian cells.
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There are several different cell types that are critical to tumor growth. In particular Endothelial Progenitor Cells are a very important cell population in tumor blood vessel growth. This finding was demonstrated in the high impact factor journals of Science (2008) and Genes and Development (2007)which also showed that Endothelial Progenitor Cells are critical for metastasis and the angiogenesis. This importance of endothelial progenitor cells in tumour growth and angiogenesis has been confirmed by a recent publication in Cancer Research (August 2010). This seminal paper has demonstrated that endothelial progenitor cells can be marked using the Inhibitor of DNA Binding 1 (ID1). This novel finding meant that investigators were able to track endothelial progenitor cells from the bone marrow to the blood to the tumour-stroma and even incorporated in tumour vasculature. This finding of endothelial progenitor cells incorporated in tumour vasculature proves the importance of this cell type in blood vessel development in a tumour setting. Furthermore, ablation of the endothelial progenitor cells in the bone marrow lead to a significant decrease in tumour growth and vasculature development. Therefore endothelial progenitor cells are very important in tumour biology and present novel therapeutic targets.
In vitro assays allow scientists to conduct studies under reasonable conditions in the lab. In order to study the communication between a tumor cell and a host cell in vitro assays have been created. The use of fragmented chicken heart cells as a host case for nutrients Thus allowing the HeLa cells to, in a sense win, and over take the PHF. In the case of the L tumor cells, they were not able to invade the PHF. Though HeLa cells were able to accomplish invasion after several hours the L cells are structurally different rendering them inadequate. The L cells have much more intercellular free space and do not surround the host cell as tightly as Hela cells. It was concluded that with a tight gap junction nutrients cannot enter the cell allowing the cancer cells to invade. With this information about the gap junction process between host cell and the tumor cell, further studies were conducted in cancer gene therapy with the use of Hela cells and the herpes virus.
The goal of oncogenomics is to identify new oncogenes or tumor suppressor genes that may provide new insights into cancer diagnosis, predicting clinical outcome of cancers, and new targets for cancer therapies. As the Cancer Genome Project stated in a 2004 review article, "a central aim of cancer research has been to identify the mutated genes that are causally implicated in oncogenesis (cancer genes)." The Cancer Genome Atlas project is a related effort investigating the genomic changes associated with cancer, while the COSMIC cancer database documents acquired genetic mutations from hundreds of thousands of human cancer samples.
These large scale projects, involving about 350 different types of tumour, have identified ~130,000 mutations in ~3000 genes that have been mutated in the tumours. The majority occurred in 319 genes of which 286 were tumour supressor genes and 33 oncogenes.
Several hereditary factors can increase the chance of cancer-causing mutations, including the activation of oncogenes or the inhibition of tumor suppressor genes. The functions of various onco- and tumor suppressor genes can be disrupted at different stages of tumor progression. Mutations in such genes can be used to classify the malignancy of a tumor.
In later stages, tumors can develop a resistance to cancer treatment. The identification of oncogenes and tumor suppressor genes is important to understand tumor progression and treatment success. The role of a given gene in cancer progression may vary tremendously, depending on the stage and type of cancer involved.
Genes and protein products that have been identified by at least two independent publications as being involved in cancer are:
ABI1, ABL2, ACSL6, AF1Q, AF5Q31 (also known as MCEF), AKT1, ARNT, ASPSCR1, ATF1, ATIC, BCL10, BFHD, BIRC3, BMPR1A, BTG1, CBFA2T1, CBFA2T3, CBFB, CCND1, CDC2, CDK4, CHIC2, CHN1, COPEB, COX6C, CTNNB1, CYLD, DDB2, DDIT3, DEK, Eif4a, EIF4A2, EPS15, ERCC2, ERCC3, ERCC5, ERG, ETV4, ETV6, EWSR1, EXT1, EXT2, FANCC, FANCG, FGFR1OP, FGFR3, FH, FIP1L1, FUS, GAS7, GATA1, GMPS, GOLGA5, GPC (gene), GPHN, HIST1H4I, HRAS, HSPCA, IL21R, IIRF4, KRAS2, LASP1, LCP1, LHFP, LMO2, LYL1, MADH4, MEIS1, MLF1, MLH1, MLLT3, MLLT6, MNAT1, MSF, MSH2, MSN, MUTYH, MYC, NCOA4, NF2, NPM1, NRAS, PAX8, PCBD, PDGFB, PHOX2B, PIM1, PLK2, PNUTL1, POU2F1, PPARG, PRCC, PRKACB, PRKAR1A, PTEN, PTPN11, RABEP1, RAD51L1, RAP1GDS1, RARA, RB1, RET, RHOH, RPL22, SBDS, SDHB, SEPTIN6, SET, SH3GL1, SS18L1, SSX1, SSX2, SSX4, STAT3, TAF15, TCF12, TCL1A, TFE3, TFEB, TFG, TFPT, TFRC, TNFRSF6, TP53, TPM3, TPM4, TRIP11, VHL, WAS, WT1, ZNF198, ZNF278, ZNF384, ZNFN1A1
Current topics of cancer treatment research include:
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Newsweek magazine published an article criticising the use of lab rats on cancer research because even though researchers frequently manage to cure lab mice transplanted with human tumors, few of those achievements are relevant to humanity. Oncologist Paul Bunn, from the International Association for the Study of Lung Cancer said: "We put a human tumor under the mouse's skin, and that microenvironment doesn't reflect a person's—the blood vessels, inflammatory cells or cells of the immune system". Fran Visco founder of the National Breast Cancer Coalition completed: "We cure cancer in animals all the time, but not in people."
Most funding for cancer research comes from taxpayers and charities, rather than from profit-making businesses. In the US, less than 30% of all cancer research is funded by commercial researchers such as pharmaceutical companies.
Per capita, public spending on cancer research by taxpayers and charities in the US is seven times as much as public spending by taxpayers and charities in the European Union. As a percentage of GDP, the non-commercial funding of cancer research in the US is four times the amount dedicated to cancer research in Europe. Half of Europe's non-commercial cancer research is funded by charitable organizations.
The organizational behavior of the large institutions and corporations that research cancer, may unduly favor low-risk research into small incremental advancements, over innovative research that might discover radically new and dramatically improved therapy.
One can share computer time for distributed cancer research projects like Help Conquer Cancer. World Community Grid also had a project called Help Defeat Cancer. Other related projects include the Folding@home and Rosetta@home projects, which focus on groundbreaking protein folding and protein structure prediction research.