Editing Cancer research (section)

== Types of research ==
Cancer research encompasses a variety of types and interdisciplinary areas of research. Scientists involved in cancer research may be trained in areas such as [[chemistry]], [[biochemistry]], [[molecular biology]], [[physiology]], [[medical physics]], [[epidemiology]], and [[biomedical engineering]]. Research performed on a foundational level is referred to as [[basic research]] and is intended to clarify scientific principles and mechanisms. [[Translational research]] aims to elucidate mechanisms of cancer development and progression and transform basic scientific findings into concepts that can be applicable to the treatment and prevention of cancer. [[Clinical research]] is devoted to the development of pharmaceuticals, surgical procedures, and medical technologies for the eventual treatment of patients.

=== Prevention and epidemiology ===

Epidemiologic analysis indicates that at least 35% of all cancer deaths in the world could now be avoided by primary prevention.<ref name="Song2018">{{cite journal |vauthors=Song M, Vogelstein B, Giovannucci EL, Willett WC, Tomasetti C |title=Cancer prevention: Molecular and epidemiologic consensus |journal=Science |volume=361 |issue=6409 |pages=1317–8 |date=September 2018 |pmid=30262488 |pmc=6260589 |doi=10.1126/science.aau3830 |bibcode=2018Sci...361.1317S }}</ref> According to a newer [[Global Burden of Disease Study|GBD]] [[Systematic review|systematic analysis]], in 2019, ~44% of all cancer deaths — or ~4.5&nbsp;million deaths or ~105&nbsp;million lost [[disability-adjusted life year]]s — were [[List of causes of death by rate#Underlying causes|due to known clearly preventable risk factors]]<!--(causal-contributing factors)-->, led by smoking, [[Health effects of alcohol|alcohol use]] and [[obesity|high BMI]].<ref name="10.1016/S0140-6736(22)01438-6">{{cite journal |last1=Tran |first1=Khanh Bao |last2=Lang |first2=Justin J. |last3=Compton |first3=Kelly |last4=Xu |first4=Rixing |last5=Acheson |first5=Alistair R. |last6=Henrikson |first6=Hannah Jacqueline |last7=Kocarnik |first7=Jonathan M. |last8=Penberthy |first8=Louise |last9=Aali |first9=Amirali |last10=Abbas |first10=Qamar |display-authors=et al. |title=The global burden of cancer attributable to risk factors, 2010–19: a systematic analysis for the Global Burden of Disease Study 2019 |journal=The Lancet |date=20 August 2022 |volume=400 |issue=10352 |pages=563–591 |doi=10.1016/S0140-6736(22)01438-6 |pmid=35988567 |pmc=9395583 |doi-access=free}}</ref>

However, one 2015 study suggested that between ~70% and ~90% of cancers are due to environmental factors and therefore potentially preventable.<ref>{{cite journal |vauthors=Wu S, Powers S, Zhu W, Hannun YA |title=Substantial contribution of extrinsic risk factors to cancer development |journal=Nature |volume=529 |issue=7584 |pages=43–7 |date=January 2016 |pmid=26675728 |pmc=4836858 |doi=10.1038/nature16166|bibcode=2016Natur.529...43W }}</ref>{{contradictory inline|date=February 2023}} Furthermore, it is estimated that with further research cancer death rates could be reduced by 70% around the world even without the development of any new therapies.<ref name = Song2018/> Cancer prevention research receives only 2–9% of global cancer research funding,<ref name = Song2018/> albeit many of the options for prevention are already well-known without further cancer-specific research but are not reflected in economics and policy. [[Mutational signatures]] of various cancers, for example, could reveal further causes of cancer and support causal attribution.<ref>{{cite journal |last1=Degasperi |first1=Andrea |last2=Zou |first2=Xueqing |last3=Dias Amarante |first3=Tauanne |last4=Martinez-Martinez |first4=Andrea |display-authors=et al. |title=Substitution mutational signatures in whole-genome–sequenced cancers in the UK population |journal=Science |date=22 April 2022 |volume=376 |issue=6591 |pages=abl9283 |doi=10.1126/science.abl9283 |pmid=35949260 |pmc=7613262 |s2cid=248334490 }}
* University press release: {{cite news |title=Largest study of whole genome sequencing data reveals 'treasure trove' of clues about causes of cancer |url=https://medicalxpress.com/news/2022-04-largest-genome-sequencing-reveals-treasure.html |access-date=15 May 2022 |work=University of Cambridge |language=en}}</ref>{{additional citation needed|date=February 2023}}

===Detection===
{{Further|Cancer screening}}
{{See also|Biomarker}}
Prompt detection of cancer is important, since it is usually more difficult to treat in later stages.  Accurate detection of cancer is also important because false positives can cause harm from unnecessary medical procedures.  Some screening protocols are currently not accurate (such as [[prostate-specific antigen]] testing).  Others such as a [[colonoscopy]] or [[mammogram]] are unpleasant and as a result some patients may opt out.  Active research is underway to address all these problems, to develop novel ways of cancer screening and to increase detection rates.{{citation needed|date=March 2019}}{{explain|date=December 2022}}

For example:
* [[Multimodal learning]] [[artificial intelligence in healthcare|AI]] systems are being developed to help detect many cancer types via [[Data integration#Medicine and Life Sciences|integrating]] different types of data.<ref>{{cite news|last1=Quach |first1=Katyanna |title=Harvard boffins build multimodal AI system to predict cancer |url=https://www.theregister.com/2022/08/09/ai_cancer_multimodal/ |access-date=16 September 2022 |work=The Register |language=en}}</ref><ref>{{cite journal |last1=Chen |first1=Richard J. |last2=Lu |first2=Ming Y. |last3=Williamson |first3=Drew F. K. |last4=Chen |first4=Tiffany Y. |last5=Lipkova |first5=Jana |last6=Noor |first6=Zahra |last7=Shaban |first7=Muhammad |last8=Shady |first8=Maha |last9=Williams |first9=Mane |last10=Joo |first10=Bumjin |last11=Mahmood |first11=Faisal |title=Pan-cancer integrative histology-genomic analysis via multimodal deep learning |journal=Cancer Cell |date=8 August 2022 |volume=40 |issue=8 |pages=865–878.e6 |doi=10.1016/j.ccell.2022.07.004 |pmid=35944502 |pmc=10397370 |s2cid=251456162 |doi-access=free }}
* Teaching hospital press release: {{cite news |title=New AI technology integrates multiple data types to predict cancer outcomes |url=https://medicalxpress.com/news/2022-08-ai-technology-multiple-cancer-outcomes.html |access-date=18 September 2022 |work=[[Brigham and Women's Hospital]] via medicalxpress.com |language=en}}</ref>
* Scientists work on identifying and measurability of novel [[biomarker]]s or sets of such to detect cancer early, such as tumor-associated [[Mycobiome#Humans|mycobiomes]] and [[Microbiome#Microbiota|bacterial microbiomes]]<ref>{{cite news |last1=Zimmer |first1=Carl |title=A New Approach to Spotting Tumors: Look for Their Microbes |url=https://www.nytimes.com/2022/09/29/science/cancer-tumors-fungi-bacteria-microbiome.html |access-date=19 October 2022 |work=The New York Times |date=29 September 2022}}</ref><ref>{{cite journal |last1=Dohlman |first1=Anders B. |last2=Klug |first2=Jared |last3=Mesko |first3=Marissa |last4=Gao |first4=Iris H. |last5=Lipkin |first5=Steven M. |last6=Shen |first6=Xiling |last7=Iliev |first7=Iliyan D. |title=A pan-cancer mycobiome analysis reveals fungal involvement in gastrointestinal and lung tumors |journal=Cell |date=29 September 2022 |volume=185 |issue=20 |pages=3807–22 |doi=10.1016/j.cell.2022.09.015 |pmid=36179671 |pmc=9564002 }}</ref><ref>{{cite journal |last1=Narunsky-Haziza |first1=Lian |last2=Sepich-Poore |first2=Gregory D. |last3=Livyatan |first3=Ilana |last4=Asraf |first4=Omer |last5=Martino |first5=Cameron |last6=Nejman |first6=Deborah |last7=Gavert |first7=Nancy |last8=Stajich |first8=Jason E. |last9=Amit |first9=Guy |last10=González |first10=Antonio |last11=Wandro |first11=Stephen |last12=Perry |first12=Gili |last13=Ariel |first13=Ruthie |last14=Meltser |first14=Arnon |last15=Shaffer |first15=Justin P. |last16=Zhu |first16=Qiyun |last17=Balint-Lahat |first17=Nora |last18=Barshack |first18=Iris |last19=Dadiani |first19=Maya |last20=Gal-Yam |first20=Einav N. |last21=Patel |first21=Sandip Pravin |last22=Bashan |first22=Amir |last23=Swafford |first23=Austin D. |last24=Pilpel |first24=Yitzhak |last25=Knight |first25=Rob |last26=Straussman |first26=Ravid |title=Pan-cancer analyses reveal cancer-type-specific fungal ecologies and bacteriome interactions |journal=Cell |date=29 September 2022 |volume=185 |issue=20 |pages=3789–3806.e17 |doi=10.1016/j.cell.2022.09.005 |pmid=36179670 |pmc=9567272 |doi-access=free}}</ref>{{explain|date=February 2023}}{{additional citation needed|date=February 2023}}
* Researchers investigate whether [[Working animal#Humans|ants could be used]] as [[biosensor]]s to detect cancer via urine<ref>{{cite journal |last1=Piqueret |first1=Baptiste |last2=Montaudon |first2=Élodie |last3=Devienne |first3=Paul |last4=Leroy |first4=Chloé |last5=Marangoni |first5=Elisabetta |last6=Sandoz |first6=Jean-Christophe |last7=d'Ettorre |first7=Patrizia |title=Ants act as olfactory bio-detectors of tumours in patient-derived xenograft mice |journal=Proceedings of the Royal Society B: Biological Sciences |date=25 January 2023 |volume=290 |issue=1991 |pages=20221962 |doi=10.1098/rspb.2022.1962 |pmid=36695032 |pmc=9874262 }}</ref>{{additional citation needed|date=February 2023}}

=== Treatment ===
{{main|Treatment of cancer}}
<!--- break this section down into:
==== Surgical research ====
==== Chemotherapy ====
==== Targeted therapy ====
==== Radiation ====
==== Other advances(?) ====
--->

Emerging topics of cancer treatment research include:

*[[Cancer vaccine|Anti-cancer vaccines]]
**[[Oncophage]]<ref name="pmid18990084">{{cite journal | vauthors = di Pietro A, Tosti G, Ferrucci PF, Testori A | title = Oncophage: step to the future for vaccine therapy in melanoma | journal = Expert Opinion on Biological Therapy | volume = 8 | issue = 12 | pages = 1973–84 | date = December 2008 | pmid = 18990084 | doi = 10.1517/14712590802517970 | s2cid = 83589014 }}</ref>
**[[Sipuleucel-T]] (Provenge) is a prostate cancer vaccine
**Inactivated tumor cells are investigated as potential bifunctional cancer vaccines<ref>{{cite journal |last1=Chen |first1=Kok-Siong |last2=Reinshagen |first2=Clemens |last3=Van Schaik |first3=Thijs A. |last4=Rossignoli |first4=Filippo |last5=Borges |first5=Paulo |last6=Mendonca |first6=Natalia Claire |last7=Abdi |first7=Reza |last8=Simon |first8=Brennan |last9=Reardon |first9=David A. |last10=Wakimoto |first10=Hiroaki |last11=Shah |first11=Khalid |title=Bifunctional cancer cell–based vaccine concomitantly drives direct tumor killing and antitumor immunity |journal=Science Translational Medicine |date=4 January 2023 |volume=15 |issue=677 |pages=eabo4778 |doi=10.1126/scitranslmed.abo4778 |pmid=36599004 |pmc=10068810 |s2cid=255416438 }}</ref>
* Newer forms of [[chemotherapy]]
*[[Gene therapy]]<ref>{{cite web | title=Gene Therapy, Cancer-Killing Viruses And New Drugs Highlight Novel Approaches To Cancer Treatment | work=Medical News Today | url=http://www.medicalnewstoday.com/medicalnews.php?newsid=68204 | access-date=24 April 2007 }}</ref><ref>{{cite web | title=World first gene therapy trial for leukaemia | work=LLR | url=http://leukaemialymphomaresearch.org.uk/research/achievements/new-treatments-blood-cancers | access-date=23 July 2013 | url-status=live | archive-url=https://web.archive.org/web/20130802091406/http://leukaemialymphomaresearch.org.uk/research/achievements/new-treatments-blood-cancers | archive-date=2 August 2013 }}</ref><ref>[https://www.nature.com/news/chinese-scientists-to-pioneer-first-human-crispr-trial-1.20302 Chinese scientists to pioneer first human CRISPR trial]</ref>
*[[Photodynamic therapy]]
*[[Radiation therapy]]
*[[Reoviridae]] (Reolysin drug therapy)
*[[Targeted therapy]]
*[[Microbotics#Medical microbots|Medical microbots]] (including bacterial),<ref>{{cite journal |last1=Schmidt |first1=Christine K. |last2=Medina-Sánchez |first2=Mariana |last3=Edmondson |first3=Richard J. |last4=Schmidt |first4=Oliver G. |title=Engineering microrobots for targeted cancer therapies from a medical perspective |journal=Nature Communications |date=5 November 2020 |volume=11 |issue=1 |pages=5618 |doi=10.1038/s41467-020-19322-7 |pmid=33154372 |pmc=7645678 |bibcode=2020NatCo..11.5618S |language=en |issn=2041-1723|doi-access=free}}</ref><ref>{{cite journal |last1=Gwisai |first1=T. |last2=Mirkhani |first2=N. |last3=Christiansen |first3=M. G. |last4=Nguyen |first4=T. T. |last5=Ling |first5=V. |last6=Schuerle |first6=S. |title=Magnetic torque–driven living microrobots for increased tumor infiltration |journal=Science Robotics |date=26 October 2022 |volume=7 |issue=71 |pages=eabo0665 |doi=10.1126/scirobotics.abo0665 |pmid=36288270 |language=en |issn=2470-9476|biorxiv=10.1101/2022.01.03.473989|s2cid=253160428 }}</ref> [[Nanobiotechnology#Nanomedicine|nanobots]]<ref>{{cite journal |last1=Kishore |first1=Chandra |last2=Bhadra |first2=Priyanka |title=Targeting Brain Cancer Cells by Nanorobot, a Promising Nanovehicle: New Challenges and Future Perspectives |journal=CNS & Neurological Disorders Drug Targets |date=July 2021 |volume=20 |issue=6 |pages=531–9 |doi=10.2174/1871527320666210526154801|pmid=34042038 |s2cid=235217854 }}</ref> and [[Cyborg#Bacterial cyborg cells|bacterial 'cyborg cells']]<ref>{{cite journal |last1=Contreras-Llano |first1=Luis E. |last2=Liu |first2=Yu-Han |last3=Henson |first3=Tanner |last4=Meyer |first4=Conary C. |last5=Baghdasaryan |first5=Ofelya |last6=Khan |first6=Shahid |last7=Lin |first7=Chi-Long |last8=Wang |first8=Aijun |last9=Hu |first9=Che-Ming J. |last10=Tan |first10=Cheemeng |title=Engineering Cyborg Bacteria Through Intracellular Hydrogelation |journal=Advanced Science |date=11 January 2023 |volume=10 |issue=9 |pages=2204175 |doi=10.1002/advs.202204175 |pmid=36628538 |pmc=10037956 |language=en |issn=2198-3844|doi-access=free}}
* News report about the study: {{cite news |last1=Firtina |first1=Nergis |title=Semi-living 'cyborg cells' could treat cancer, suggests new study |url=https://interestingengineering.com/health/semi-living-cyborg-cells-treat-cancer |access-date=15 February 2023 |work=Interesting Engineering |date=1 February 2023 |archive-date=15 February 2023 |archive-url=https://web.archive.org/web/20230215185036/https://interestingengineering.com/health/semi-living-cyborg-cells-treat-cancer |url-status=live }}</ref>{{additional citation needed|date=February 2023}}
* [[Virotherapy#Cancer treatment|Virotherapy]]<ref>{{cite journal |last1=Lawler |first1=Sean E. |last2=Speranza |first2=Maria-Carmela |last3=Cho |first3=Choi-Fong |last4=Chiocca |first4=E. Antonio |title=Oncolytic Viruses in Cancer Treatment: A Review |journal=JAMA Oncology |date=1 June 2017 |volume=3 |issue=6 |pages=841–9 |doi=10.1001/jamaoncol.2016.2064|pmid=27441411 |s2cid=39321536 |doi-access=free }}</ref><ref>{{cite journal |last1=Harrington |first1=Kevin |last2=Freeman |first2=Daniel J. |last3=Kelly |first3=Beth |last4=Harper |first4=James |last5=Soria |first5=Jean-Charles |title=Optimizing oncolytic virotherapy in cancer treatment |journal=Nature Reviews Drug Discovery |date=September 2019 |volume=18 |issue=9 |pages=689–706 |doi=10.1038/s41573-019-0029-0 |pmid=31292532 |s2cid=256745869 |language=en |issn=1474-1784}}</ref>
* [[Antibodies]]<ref>{{cite news |last1=Osborne |first1=Margaret |title=Small Cancer Trial Resulted in Complete Remission for All Participants |url=https://www.smithsonianmag.com/smart-news/small-cancer-trial-resulted-in-complete-remission-for-all-participants-180980221/ |access-date=21 July 2022 |work=Smithsonian Magazine |language=en}}</ref><ref>{{cite journal |last1=Cercek |first1=Andrea |last2=Lumish |first2=Melissa |last3=Sinopoli |first3=Jenna |last4=Weiss |first4=Jill |last5=Shia |first5=Jinru |last6=Lamendola-Essel |first6=Michelle |last7=El Dika |first7=Imane H. |last8=Segal |first8=Neil |last9=Shcherba |first9=Marina |last10=Sugarman |first10=Ryan |last11=Stadler |first11=Zsofia |last12=Yaeger |first12=Rona |last13=Smith |first13=J. Joshua |last14=Rousseau |first14=Benoit |last15=Argiles |first15=Guillem |last16=Patel |first16=Miteshkumar |last17=Desai |first17=Avni |last18=Saltz |first18=Leonard B. |last19=Widmar |first19=Maria |last20=Iyer |first20=Krishna |last21=Zhang |first21=Janie |last22=Gianino |first22=Nicole |last23=Crane |first23=Christopher |last24=Romesser |first24=Paul B. |last25=Pappou |first25=Emmanouil P. |last26=Paty |first26=Philip |last27=Garcia-Aguilar |first27=Julio |last28=Gonen |first28=Mithat |last29=Gollub |first29=Marc |last30=Weiser |first30=Martin R. |last31=Schalper |first31=Kurt A. |last32=Diaz |first32=Luis A. |title=PD-1 Blockade in Mismatch Repair–Deficient, Locally Advanced Rectal Cancer |journal=New England Journal of Medicine |date=23 June 2022 |volume=386 |issue=25 |pages=2363–76 |doi=10.1056/NEJMoa2201445 |pmid=35660797 |pmc=9492301 |s2cid=249395846 |issn=0028-4793}}</ref><ref>{{cite news |title=Trastuzumab Deruxtecan Leads to Longer PFS and OS Compared with Chemotherapy in Previously Treated HER2-Low Unresectable or Metastatic Breast Cancer |url=https://www.esmo.org/oncology-news/trastuzumab-deruxtecan-leads-to-longer-pfs-and-os-compared-with-chemotherapy-in-previously-treated-her2-low-unresectable-or-metastatic-breast-cancer |access-date=21 July 2022 |work=www.esmo.org}}</ref><ref>{{cite journal |last1=Modi |first1=Shanu |last2=Jacot |first2=William |last3=Yamashita |first3=Toshinari |last4=Sohn |first4=Joohyuk |last5=Vidal |first5=Maria |last6=Tokunaga |first6=Eriko |last7=Tsurutani |first7=Junji |last8=Ueno |first8=Naoto T. |last9=Prat |first9=Aleix |last10=Chae |first10=Yee Soo |last11=Lee |first11=Keun Seok |last12=Niikura |first12=Naoki |last13=Park |first13=Yeon Hee |last14=Xu |first14=Binghe |last15=Wang |first15=Xiaojia |last16=Gil-Gil |first16=Miguel |last17=Li |first17=Wei |last18=Pierga |first18=Jean-Yves |last19=Im |first19=Seock-Ah |last20=Moore |first20=Halle C. F. |last21=Rugo |first21=Hope S. |last22=Yerushalmi |first22=Rinat |last23=Zagouri |first23=Flora |last24=Gombos |first24=Andrea |last25=Kim |first25=Sung-Bae |last26=Liu |first26=Qiang |last27=Luo |first27=Ting |last28=Saura |first28=Cristina |last29=Schmid |first29=Peter |last30=Sun |first30=Tao |last31=Gambhire |first31=Dhiraj |last32=Yung |first32=Lotus |last33=Wang |first33=Yibin |last34=Singh |first34=Jasmeet |last35=Vitazka |first35=Patrik |last36=Meinhardt |first36=Gerold |last37=Harbeck |first37=Nadia |last38=Cameron |first38=David A. |title=Trastuzumab Deruxtecan in Previously Treated HER2-Low Advanced Breast Cancer |journal=New England Journal of Medicine |date=5 June 2022 |volume=387 |issue=1 |pages=9–20 |doi=10.1056/NEJMoa2203690 |pmid=35665782 |pmc=10561652 |hdl=2445/197309 |s2cid=249418284 |url=https://www.research.ed.ac.uk/en/publications/4095995e-3067-46c9-875a-a70cdb641427 |language=en|hdl-access=free }}</ref>{{additional citation needed|date=December 2022}}
* [[Photoimmunotherapy]] (for [[brain cancer]])<ref>{{cite web | url=https://www.theguardian.com/society/2022/jun/17/scientists-harness-light-therapy-to-target-and-kill-cancer-cells-in-world-first |title=Scientists harness light therapy to target and kill cancer cells in world first |work=The Guardian| date=17 June 2022| access-date=21 June 2022}}</ref><ref>{{cite journal |last1=Mączyńska |first1=Justyna |last2=Raes |first2=Florian |last3=Da Pieve |first3=Chiara |last4=Turnock |first4=Stephen |last5=Boult |first5=Jessica K. R. |last6=Hoebart |first6=Julia |last7=Niedbala |first7=Marcin |last8=Robinson |first8=Simon P. |last9=Harrington |first9=Kevin J. |last10=Kaspera |first10=Wojciech |last11=Kramer-Marek |first11=Gabriela |title=Triggering anti-GBM immune response with EGFR-mediated photoimmunotherapy |journal=BMC Medicine |date=21 January 2022 |volume=20 |issue=1 |pages=16 |doi=10.1186/s12916-021-02213-z |pmid=35057796 |pmc=8780306 |issn=1741-7015 |doi-access=free }}
* News release: {{cite web | url=https://www.icr.ac.uk/news-archive/light-activated-photoimmunotherapy-could-enhance-brain-cancer-treatment |title=Light-activated 'photoimmunotherapy' could enhance brain cancer treatment |work=Institute of Cancer Research| date=16 June 2022| access-date=21 June 2022}}</ref>{{additional citation needed|date=December 2022}}
*[[Natural killer cell]]s can induce [[immunological memory]].<ref name="CerwenkaLanier2016" /> Research is being developed to modify their action against cancer.<ref name="CerwenkaLanier2016">{{cite journal | vauthors = Cerwenka A, Lanier LL | title = Natural killer cell memory in infection, inflammation and cancer | journal = Nature Reviews. Immunology | volume = 16 | issue = 2 | pages = 112–123 | date = February 2016 | pmid = 26806484 | doi = 10.1038/nri.2015.9 | s2cid = 361806 | url = http://www.escholarship.org/uc/item/2qj442xk }}</ref>
*How treatments can best be combined (in [[combination therapies]])<ref>{{cite journal |last1=Zhu |first1=Shaoming |last2=Zhang |first2=Tian |last3=Zheng |first3=Lei |last4=Liu |first4=Hongtao |last5=Song |first5=Wenru |last6=Liu |first6=Delong |last7=Li |first7=Zihai |last8=Pan |first8=Chong-xian |title=Combination strategies to maximize the benefits of cancer immunotherapy |journal=Journal of Hematology & Oncology |date=December 2021 |volume=14 |issue=1 |pages=156 |doi=10.1186/s13045-021-01164-5|pmid=34579759 |pmc=8475356 |doi-access=free }}</ref>

=== Cause and development of cancer ===
[[File:Signal transduction v1.png|thumb|350px|Numerous [[cell signaling]] pathways are disrupted in the development of cancer.]]

Research into the cause of cancer 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 the aim to test safety and efficiency of the therapeutic intervention method.
An important part of basic research is characterization of the potential 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.

==== Genes involved in cancer ====
{{main|Oncogenomics}}
{{See also|Databases for oncogenomic research}}
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'')."<ref name="pmid14993899">{{cite journal | vauthors = Futreal PA, Coin L, Marshall M, Down T, Hubbard T, Wooster R, Rahman N, Stratton MR | title = A census of human cancer genes | journal = Nature Reviews. Cancer | volume = 4 | issue = 3 | pages = 177–183 | date = March 2004 | pmid = 14993899 | pmc = 2665285 | doi = 10.1038/nrc1299 }}</ref> [[The Cancer Genome Atlas]] project is a related effort investigating the genomic changes associated with cancer, while the [[COSMIC cancer database]] documents acquired genetic [[mutation]]s from hundreds of thousands of human cancer samples.<ref name="pmid16421597">{{cite journal | vauthors = Forbes S, Clements J, Dawson E, Bamford S, Webb T, Dogan A, Flanagan A, Teague J, Wooster R, Futreal PA, Stratton MR | title = COSMIC 2005 | journal = British Journal of Cancer | volume = 94 | issue = 2 | pages = 318–322 | date = January 2006 | pmid = 16421597 | pmc = 2361125 | doi = 10.1038/sj.bjc.6602928 }}</ref>

These large scale projects, involving about 350 different types of cancer, have identified ~130,000 [[mutation]]s in ~3000 [[genes]] that have been mutated in the tumors. The majority occurred in 319 genes, of which 286 were tumor suppressor 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. <!-- What does this last sentence mean?/! -->

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.<ref>Vlahopoulos SA, Logotheti S, Mikas D, Giarika A, Gorgoulis V, Zoumpourlis V.The role of ATF-2 in oncogenesis" ''Bioessays'' 2008 Apr;30(4) 314-27.</ref>

==== Cancer epigenetics ====
{{Excerpt|Cancer epigenetics|only=paragraphs}}