Ib qho oncogene yog ib hom cellular uas nws cov lus qhia yuav txhawb txoj kev loj hlob ntawm qog noj ntshav. Dab tsi yog qhov txawv ntawm oncogenes? Los ntawm dab tsi mechanisms lawv qhib? Kev piav qhia.

Ib qho oncogene (los ntawm Greek onkos, qog thiab genos, yug) kuj hu ua proto-oncogene (c-onc) yog cov noob uas nws cov lus qhia yuav ua rau muaj mob qog noj ntshav ntawm lub cev ib txwm muaj eukaryotic. Tseeb, oncogenes tswj cov synthesis ntawm cov proteins uas txhawb kev faib cell (hu ua oncoproteins) los yog inhibit programmed cell tuag (los yog apoptosis). Oncogenes yog lub luag haujlwm rau kev tswj tsis tau cov cell proliferation predisposing rau kev loj hlob ntawm cov qog nqaij hlav cancer.

Oncogenes muab faib ua 6 chav kawm uas sib raug raws li oncoproteins lawv encode:

• yam loj hlob. Piv txwv li: proto-oncogene encoding proteins ntawm tsev neeg FGF (Fibroblast Growth Factor);
• transmembrane loj hlob factor receptors. Piv txwv li: proto-oncogene erb B uas codes rau EGF (Epidermal Growth Factor) receptor;
• G-proteins lossis membrane proteins khi GTP. Piv txwv li: proto-oncogenes ntawm tsev neeg ras;
• membrane tyrosine protein kinases;
• cov protein kinases;
• proteins nrog kev ua haujlwm nuclear.Piv txwv li: proto-oncogenes erb A, phos, Lub rau hli ntuj et c-miv.

Cell txuas ntxiv yog ua kom tiav los ntawm lub voj voog ntawm tes. Cov yav tas yog txhais los ntawm ib txheej txheej xwm uas tsim tau ob tug ntxhais cell los ntawm niam cell. Peb tham txog cell faib los yog "mitosis".

Lub voj voog ntawm tes yuav tsum tau tswj. Tseeb, yog tias kev faib cell tsis txaus, lub cev tsis ua haujlwm zoo; Piv txwv li, yog hais tias cell division muaj ntau, hlwb proliferate uncontrollably, uas txhawb cov tsos ntawm cov qog nqaij hlav cancer.

Cov kev cai ntawm lub voj voog ntawm tes yog lav los ntawm cov noob tau muab faib ua ob pawg:

• anti-oncogenes uas inhibit cell proliferation los ntawm slowing lub cell voj voog;
• proto-oncogenes (c-onc) lossis oncogenes uas txhawb kev loj hlob ntawm tes los ntawm kev ua kom lub voj voog ntawm tes.

Yog tias peb piv lub voj voog ntawm tes mus rau lub tsheb, cov tshuaj tiv thaiv oncogenes yuav yog tus nres thiab cov proto-oncogenes yuav yog cov accelerators tom kawg.

Qhov tsos Cov qog nqaij hlav tuaj yeem tshwm sim los ntawm kev hloov pauv tsis ua haujlwm los tiv thaiv oncogenes lossis ntawm qhov tsis sib xws los ntawm kev hloov pauv ua kom proto-oncogenes (lossis oncogenes).

Kev poob ntawm kev ua haujlwm ntawm cov tshuaj tiv thaiv oncogenes tiv thaiv lawv los ntawm kev ua lawv cov cell proliferation inhibitory kev ua. Qhov inhibition ntawm anti-oncogenes yog lub qhov rooj qhib rau uncontrolled cell division uas yuav ua rau cov tsos ntawm malignant hlwb.

Txawm li cas los xij, cov tshuaj tiv thaiv oncogenes yog cov noob ntawm tes, uas yog, lawv muaj nyob rau hauv duplicate ntawm ob chromosomes uas nqa lawv nyob rau hauv lub nucleus ntawm lub cell. Yog li, thaum ib daim qauv ntawm cov tshuaj tiv thaiv oncogene tsis ua haujlwm, lwm qhov ua rau nws tuaj yeem ua tus nres kom cov ntsiab lus tiv thaiv kev loj hlob ntawm tes thiab tiv thaiv kev pheej hmoo ntawm cov qog. Qhov no yog qhov xwm txheej, piv txwv li, ntawm BRCA1 noob, qhov inhibitory kev hloov pauv uas nthuav tawm cov qog nqaij hlav mis. Tab sis yog tias daim ntawv thib ob ntawm cov noob no ua haujlwm tau zoo, tus neeg mob tseem muaj kev tiv thaiv txawm hais tias nws tau raug pov thawj vim qhov tsis zoo thawj daim ntawv. Raws li ib feem ntawm xws li ib tug predisposition, kev tiv thaiv ob mastectomy yog tej zaum txiav txim siab.

Hloov pauv, qhov kev hloov pauv hloov pauv cuam tshuam rau proto-oncogenes accentuates lawv cov nyhuv stimulating ntawm cell proliferation. Qhov no anarchic cell proliferation predisposes rau kev loj hlob ntawm cov qog nqaij hlav.

Ib yam li anti-oncogenes, pro-oncogenes yog cellular genes, tam sim no nyob rau hauv duplicate ntawm ob chromosomes uas nqa lawv. Txawm li cas los xij, tsis zoo li cov tshuaj tiv thaiv oncongens, muaj ib qho kev hloov pauv ntawm pro-oncogene txaus los tsim cov teebmeem kev ntshai (qhov no, cell proliferation). Yog li ntawd, tus neeg mob nqa qhov kev hloov pauv no yuav muaj feem yuav mob qog noj ntshav.

Kev hloov pauv hauv oncogenes tuaj yeem tshwm sim, keeb kwm lossis txawm tshwm sim los ntawm mutagens (tshwj xeeb, UV rays, thiab lwm yam).

Ob peb lub tswv yim yog nyob rau hauv keeb kwm ntawm activating mutations ntawm oncogenes los yog pro-oncogenes (c-onc):

• Kev sib xyaw ua ke ntawm tus kab mob: tso cov kab mob DNA ntawm qib ntawm kev tswj hwm noob. Qhov no yog piv txwv li rooj plaub ntawm human papillomavirus (HPV), uas kis tau los ntawm kev sib deev;
• taw tes kev hloov pauv nyob rau hauv ib ntu ntawm cov noob encoding cov protein;
• kev tshem tawm: poob ntawm qhov loj lossis me me ntawm DNA, ua rau muaj kev hloov pauv ntawm caj ces;
• kev hloov kho cov qauv: chromosomal alteration (translocation, inversion) ua rau kev tsim cov noob hybrid encoding ib qho protein uas tsis ua haujlwm;
• amplification: txawv txav ntau ntawm cov ntawv luam ntawm cov noob hauv lub cell. Qhov kev nthuav dav no feem ntau ua rau nce qib ntawm kev qhia ntawm cov noob;
• lub deregulation ntawm kev qhia ntawm ib tug RNA: cov noob yog disconnected los ntawm lawv ib txwm molecular ib puag ncig thiab muab tso rau nyob rau hauv tsis tsim nyog tswj ntawm lwm yam sequences ua rau ib tug hloov ntawm lawv cov kev qhia.

Genes encoding yam loj hlob los yog lawv cov receptors:

• PDGF: encodes platelet loj hlob yam cuam tshuam nrog glioma (mob qog noj ntshav ntawm lub hlwb);
  Erb-B: encodes lub epidermal loj hlob yam receptor. Koom nrog glioblastoma (mob qog noj ntshav ntawm lub hlwb) thiab mob qog noj ntshav mis;
• Erb-B2 kuj hu ua HER-2 los yog neu: encodes ib qho kev loj hlob receptor. Ua ke nrog lub mis, qog qaub ncaug thiab qog noj ntshav ntawm zes qe menyuam;
• RET: encodes ib qho kev loj hlob zoo receptor. Koom nrog cov thyroid cancer.

Genes encoding cytoplasmic relays nyob rau hauv txoj kev stimulation:

• Ki-ras: cuam tshuam nrog lub ntsws, zes qe menyuam, plab hnyuv thiab pancreatic cancer;
• N-ras: txuam nrog leukemia.

Genes encoding transcription yam uas qhib kev loj hlob txhawb cov noob:

• C-myc: txuam nrog leukemia thiab mis, plab thiab ntsws cancer;
• N-myc: txuam nrog neuroblastoma (mob qog noj ntshav ntawm paj hlwb) thiab glioblastoma;
• L-myc: txuam nrog mob ntsws cancer.

Genes encoding lwm molecules:

• Hcl-2: encodes cov protein uas ib txwm thaiv cov cell suicide. Txuas nrog lymphomas ntawm B lymphocytes;
• Bel-1: kuj hu ua PRAD1. Encodes Cyclin DXNUMX, ib lub voj voog ntawm tes ua haujlwm. Koom nrog mob qog noj ntshav mis, taub hau thiab caj dab;
• MDM2: encodes tus antagonist ntawm cov protein uas tsim los ntawm cov qog suppressor noob.
• P53: cuam tshuam nrog sarcomas (cov qog nqaij hlav sib txuas) thiab lwm yam qog noj ntshav.

Cov kab mob oncogenic yog cov kab mob uas muaj peev xwm ua rau cov cell lawv kis mob cancer. 15% ntawm cov qog nqaij hlav muaj tus kab mob etiology thiab cov kab mob qog noj ntshav no yog qhov ua rau kwv yees li 1.5 lab tus neeg mob tshiab hauv ib xyoos thiab 900 tus neeg tuag hauv ib xyoos thoob ntiaj teb.

Associated viral cancers yog ib qho teeb meem kev noj qab haus huv rau pej xeem:

• tus kab mob papillomavirus yog txuam nrog ze li 90% ntawm cov qog nqaij hlav hauv tsev menyuam;
• 75% ntawm tag nrho cov kab mob siab hepatocarcinoma txuas rau kab mob siab B thiab C.

Muaj tsib pawg ntawm cov kab mob oncogenic, txawm tias lawv yog cov kab mob RNA lossis cov kab mob DNA.

Cov kab mob RNA

• Retroviridae (HTVL-1) ua rau koj muaj kev pheej hmoo ntawm T leukemia;
• Flaviviridae (tus kab mob siab C) muaj kev pheej hmoo rau hepatocellular carcinoma.

DNA kab mob

• Papovaviridae (papillomavirus 16 thiab 18) ua rau mob qog noj ntshav ntawm lub ncauj tsev menyuam;
• Herpesviridae (Esptein Barr virus) kis rau B lymphoma thiab carcinoma;
• Herpesviridae (tib neeg herpesvirus 8) nthuav tawm Kaposi tus kab mob thiab lymphomas;
• Hepadnaviridae (tus kab mob siab B) yog raug rau kab mob hepatocellular carcinoma.