Izidalwa zezilwanyana ezixhatshazwayo - Imisebenzi, ukungavumelekanga, kunye nendima kwiCarcer
Ziziphi izidalwa zengcinezelo zengqumbo? Zihluke njani ezi zinto kunama-oncogenes, kwaye yintoni indima abayidlala ngayo ekuphuhliseni umdlavuza kunye nomhlaza wesizalo?
Inkcazo: Izidalwa zoLondolozo lweZindlebe
Izidalwa zengqungquthela zengcinezelo zengqungquthela zendalo ezilawula ukukhula kweeseli. Xa ezi jeni zisebenza ngokufanelekileyo, zinokuthintela kwaye zivimbele ukukhula kwezidumbu.
Xa i-genetic suppressor genes ishintshiwe okanye ingasebenzi (ngenxa yokuguquka), ilahlekelwa amandla okwenza iprotheni elawula ukukhula kweseli.
Iiselula zingakhula zingalawulwa kwaye zikhule zibe ngumhlaza.
Iintlobo zeGenesis ye-Tumor Suppressor
Kukho iintlobo ezi-3 eziphambili ze-tumor suppressor jeni.
- Olunye uhlobo luxelela iiseli ukuba zinciphise kwaye ziyeke ukuhlula.
- Olunye uhlobo lujongene nokulungisa umonakalo kwi-DNA eyenzekayo xa amaseli ahlula (i-DNA repair genes.)
- Uhlobo lwesithathu lujongene nokuxelela iiseli xa sifa, inkqubo ebizwa ngokuba yi-apoptosis okanye ukufa kweseli ehleliweyo.
I-Analogy Ukuqhuba - Izidalwa zokuSondeza iziHlomelo zeziBrakes
Kuzo zonke iindaba malunga ne-immunotherapy , kunye nezixhobo zokuva kunye neengcezu malunga "nokucima ukutshintsha" umhlaza, kunokunceda, ngokulula, ucinge ngeeseli njengemoto. Kwiseli nganye, kukho i-acceleration and brakes. Kwiimoto eziqhelekileyo, zombini zisebenza kakuhle. Iinkqubo ezininzi ziqinisekisa ukuba zihlala zilinganise kangangokuba imoto iyahamba rhoqo rhoqo, kodwa ayiyi kuphazamiseka.
I-Cancer iqala ngoluhlu lweenguqulelo. Olunye utshintsho alunanto enkulu-siyabhekisela kubo njengenguquko yomgibeli.
Iimpembelelo zeengxaki ziquka ezo ziquka umqhubi. Umqhubi unokuthatha isigqibo sokuhamba ngokukhawuleza okanye ngokukhawuleza. Unokuva malunga nale "njengentshukumo yomqhubi" kungekhona ngenxa yokuba baqhuba imoto, kodwa ngenxa yokuba baqhuba ukukhula kweeseli zomhlaza.
I-Cancer inxulumene neengxaki ezinokuthi i-accelerator okanye iibhuleki, kodwa ngokuqhelekileyo, umonakalo kumajeni okulawula ezo zombini zifunekayo ukuze kubangele umhlaza.
Inyaniso yokuba umdlavuza ufuna ukuba utshintsho oluthile luyinye yezizathu zokuba umhlaza uqheleke kangakanani kubantu abadala.
I-Oncogenes , ngokufana, izakhi zolawulo ezilawula i-accelerator. Ixesha elithi oncogenes lithetha ngokoqobo "umhlaza wesifo somhlaza."
Ukuxhatshazwa kwezilwanyana zegciwane , ngokungafani ne-oncogenes, iibhuleki. Izifo zengcinezelo zengcinezelo zenza njengeprogram. Ziya khokela iiprotheni eziye zinoxanduva lokuphuma nokubetha amabheki.
Uninzi lwexesha lokuba iseli ibe ngumhlaza, ludinga ukuguqulwa kwamagqabini kunye neentsholongwane zengcinezelo zenyama. Ngamanye amagama, i-accelerator kufuneka ibambelele phantsi kwaye i-brakes kufuneka ibenzi.
I-Oncogenes vs i-Tumor Suppressor Genes
Kukho ulwahlulo olubalulekileyo phakathi kwama-oncogenes kunye neengcinezelo zentsholongwane zesifo somhlaza kumhlaza. Ngokubanzi, i-oncogenes iphezulu . Kwimizimba yethu, sinamaqoqo amabini e-chromosomes nganye kunye neeseti ezimbini zegesi-enye ukusuka kubazali bethu. Ngokuqhelekileyo ukuba enye imfuyo ayisebenzi kakuhle, enye ingakwazi ukuhlawula. Usenokuba ulivile ngelifa. Ukuba uvile ngelifa lombala wamehlo, umahluko phakathi kwama-oncogenes amaninzi kunye neengcinezelo zokugulisa i-tumor kulula ukuqonda. I-Oncogenes ithambekele ekubeni yinto ephezulu-njengamabala omdaka.
Ukuba enye yegesi ingashenxisa i-accelerator nzima, inokufaka isandla kumdlavuza. Ukuxhatshazwa kweengcambu zengqungquthela, ngokuphambene, zithatha ukugqithisa . Okokuthi, njengokuba udinga iigenki ezimbini zamehlo aluhlaza ukuze unabantwana obuhlaza okwesibhakabhaka, ezimbini zezilwanyana ezixhasayo kufuneka zonakaliswe zombini ukuze zenze umdlavuza.
Izidalwa zezilwanyana ezixhasayo kunye nefa elibuyiselwayo - "2 Hit Hypothesis"
Ukuqonda ukuziphatha okugqithisileyo kwimizimba yokunyamezela i-tumor kunokusinceda ekuqondeni izidalwa zendalo ezibangelwa isifo.
Umzekelo umxhatshazo weengcambu zegciwane BRCA1 / BRCA2 - enye into eyaziwa ngokuba yi "gene genes". Abantu abanokuguqulwa komnye kula majelo enomhlaza banomngcipheko okhulayo wokuba nomdlavuza webele (phakathi kwabanye.) Kodwa akubona bonke abantu abanomdlavuza abanomdlavuza wesibele.
Xa i-gene engatshintshiyo iguqulwe, ukuguqulwa okufumeneyo, oku kuthetha ukuguqulwa komntu okwenzeka emva kokuzalwa, umhlaza ungabangela.
Ubume obunokugqithiseleyo yinto ekubhekiswa kuyo ukuba uva "i-2 hit hit" yomhlaza. Ezinye iintsholongwane ziqala (ubuncinci kwi-tumor suppressor ekupheleni, kodwa gcinani engqondweni ukuba kukho ukuguquguquka kwe-oncogene kwakhona) emva kokutshintshwa kwe-2 kwi-genetic infressor gene. Inguqu yokuqala ingase ibe khona ukusuka ekuzalweni, eyaziwa ngokuthi "ukuguquka kwegciwane." Okwesibini, "ukuguqulwa kwamathambo" kufumaneka kwaye kuhambelana nento kwimeko emva kokuzalwa.
Imbali
Izidalwa zokugonywa kweengcambu zaqala ukubonakala phakathi kwabantwana abane-retinoblastoma. Kwi-retinoblastoma, ngokuphambene, i-genetic suppressor gene ezuze ilifa-kwaye ke vumela iidlers ukuba ziphuhlise kubantwana abancinci.
IGenesis Suppressor Genes
Kukho ngoku sele kuninzi i-tumor suppressor geni echazwe. Ezinye zezi ziquka:
- RB - I-genetic suppressor gene ejongene ne-retinoblastoma
- i-p53 gene - Iikhowudi ze-p53 zofuzo zeprotheyini p53 .which ilawula ukulungiswa kwemfuza kwiiseli. Ukuguqulwa kwenguqu kule mfuza kubandakanyeka kuma-50 ekhulwini.
- B RCA1 / BRCA2 - Ezi zityalo zinoxanduva malunga neepesenti ezi-5 ukuya kwi-10 ekhulwini zeengcingo zebele. (I- BRCA2 idibaniswe nomngcipheko womhlaza wamaphaphu kwabasetyhini .)
- I-APC yegeni - Ezi ntlobo zegciwane zidibene nomngcipheko wokwanda komdlavuza wekoloni kubantu abane-familial adenomatous polyposis.
Kutheni ukunyanga kwamaKhankaso akusoloko usebenza
Ukuqonda i-tumor suppressor jeni kunokukunceda ukuba uchaze isizathu sokuba unyango, njengokhemotherapy, aluphilisi ngokupheleleyo umdlavuza. Olunye unyango lomhlaza lusebenza ukukhuthaza amangqamuzana ukuba azibulale. Ekubeni ezinye izifo zengcinezelo zentsholongwane zibandakanyeka kwinkqubo ye-apoptosis (ukufa kweseli) iiseli zomhlaza zingangena kwinkqubo ye-apoptosis njengoko ezinye iiseli zinokwenzeka.
Olongezelelweyo Ngomdlavuza
Ukufunda malunga neengcambu zokuxhaswa kweengcambu kuyingxenye enye yokuqonda ukuphuhliswa nokusinda komhlaza. Funda ngokuchanekileyo yintoni iseli somhlaza , kunye nendlela amangqamuzana omhlaza ahluke ngayo kwiiseli eziqhelekileyo .
Kwaziwa kwakhona njenge: antioncogene, ukulahleka kwemisebenzi yendalo
Imizekelo: Amaninzi omdlavuza wamaphaphu anomzimba ongaqhelekanga we-p53 kwisisu. i-p53 yindoda yokuxhaphaza i-tumor ejongene nokuqinisekisa ukuba iiseli ziyafa ukuba iDNA yazo yonakaliswe kwaye ayikwazi ukulungiswa (apoptosis).
> Imithombo:
> I-American Cancer Society. I-Oncogenes ne-Tumor Suppressor Genes. Ukuhlaziywa 06/25/14. http://www.cancer.org/cancer/cancercauses/geneticsandcancer/genesandcancer/genes-and-cancer-oncogenes-tumor-suppressor-genes