I-biopsies yamanzi isebenzisa igazi-hhayi izicubu zesisu-ukuxilonga umdlavuza
Ngokujwayelekile, izicubu zihlolwa ngokusetshenziswa kwezicubu zezinyosi. Isampula encane ithathwe ku-tumor kanye ne-genotyped, noma ihlaziywe ukwenza i-genetic makeup. Inkinga ngale ndlela iwukuthi izicubu ezinobuthi zingaba yinselele. Ngaphezu kwalokho, i-biopsy ye-tumor inikeza kuphela isifenqo se-tumor.
Ukubhala Ekutholeni Imithi ngo-2015, uLabgaa kanye nabalobi ababambisene nabo babika lokhu okulandelayo mayelana ne-tumor biopsy evamile:
Ngezizathu ezicacile, kunzima ukuqapha ukubola kwemvelo nge-biopsies elandelanayo. Futhi, i-biopsy ibonisa kuphela indawo eyodwa ye-tumor ngakho-ke ayikwazi ukumela yonke into eguquguqukayo ye-somatic ezithombeni ezinkulu. Enye ingaba ukuthola ama-biopsi amaningi amaningi, kepha lokhu kubonakala kubonakala kungokoqobo noma kunembile.
I-biopsy yamanzi ihilela ukulinganisa kokudlulisa i-DNA (ctDNA) kanye nezinye izifo ezinamahlumela ezingxenyeni zegazi ezitholakala ezigulini ezine-cancer. Le ndlela yokuhlonza evelayo iqinisekisa ukuthi iyashesha, ingenasidingo, futhi iyabiza.
Umlando we-Liquid Biopsy
Ngo-1948, uMandel noMétais, abacwaningi ababili baseFrance baqala ukubona i-cNA egazini labantu abaphilile. Lokhu kutholakala kwakungaphambi kwesikhathi sayo, futhi kwaze kwaphela amashumi eminyaka ukuthi i-ctDNA yaqhutshwa phambili.
Ngo-1977, uLeon nabasebenza nabo baqala ukuthola inani elengeziwe le-ctDNA egazini leziguli zomdlavuza.
Ngomnyaka ka-1989, iStroun kanye nabasebenza nabo bahlonze izici ze-neoplastic (okungukuthi, umdlavuza) egazini. Emva kwalokhu kutholakala, amanye amaqembu amaningana aveza ukuguqulwa okuqondile kwe-tumor suppressors kanye ne-oncogenes, ukungabi khona kwe-microsatellite, ne-DNA methylation, efakazela ukuthi i-ctDNA ikhishwa ekuhambeni kwegazi.
Nakuba siyazi ukuthi i-ctDNA etholakala emangqamuzaneni amangqamuzana egazini, umsuka, isilinganiso sokukhululwa, nendlela yokukhululwa kwaleli DNA akucacile, ucwaningo lwenza imiphumela ephikisanayo. Olunye ucwaningo lubonisa ukuthi ezinye izicubu ezinonya ziqukethe amangqamuzana omdlavuza omningi futhi zikhulule i-ctDNA ngaphezulu. Noma kunjalo, ucwaningo oluthile lubonisa ukuthi wonke amaseli akhipha i-ctDNA. Noma kunjalo, kubonakala sengathi izicubu zomdlavuza zikhulula amazinga e-ctDNA egazini, okwenza i-ctDNA ibe yi-biomarker enhle yomdlavuza.
Ngenxa yokuhlukaniswa okukhulu nokugxila okuphansi egazini, i-ctDNA kunzima ukuhlukanisa nokuhlaziya. Kunokungafani kwamakhemikhali e-ctDNA phakathi kwamasampuli e-serum nama-plasma. Kubonakala sengathi i-serum yegazi esikhundleni se-plasma yegazi ingumthombo ongcono we-ctDNA. Esicwaningweni sika-Umetani nabalingani bakhe, ama-ct ADN ayatholakala ephansi e-plasma uma kuqhathaniswa ne-serum ngenxa yokulahlekelwa kwe-DNA ngesikhathi sokuhlanzwa, njengoba ama-coagulation namanye amaprotheni aqedwa ngesikhathi sokulungiselela.
Ngokusho kukaHeitzer nozakwabo, nansi ezinye izinto ezidingekayo ukuthi zixazululwe ukuze zikwazi ukuhlolisisa i-ctDNA:
Okokuqala, izinqubo zangaphambi kokudinga zidinga ukulinganiselwa .... Ukukhethwa kwendlela yokwehlukanisa okuqinisekisa ukukhishwa kwesilinganiso esanele se-DNA ephezulu kakhulu futhi kuboniswe ukuthi izici zangaphambili ze-sampling yegazi kanye nokucubungula zingathinta kakhulu i-DNA isivuno .... Okwesibili, enye yezindaba ezibaluleke kakhulu ukungabi nokuvumelanisa kwezindlela ze-quantification. Izindlela ze-quantification ezahlukene, ... ukukhiqiza imiphumela ehlukene ngoba lezi zilinganiso zibheke noma yi-DNA engqikithi noma kuphela .... Okwesithathu, kuncane okuyaziwa ngemvelaphi kanye nenqubo eningiliziwe yokukhululwa kwe-ctDNA, futhi ezikhathini eziningi izifundo eziningi ziphazamisa izenzakalo ezingase zenze futhi ekukhululweni kwe-ctDNA.
Izinkambiso ezibhekelelwa nokungaqaliwe
Njengamanje, kunezindlela ezimbili eziyinhloko ezithathwe lapho kuhlaziywa i-plasma yegazi (noma i-serum) ye-ctDNA. Indlela yokuqala ihloswe futhi ibuke izinguquko ezithile zofuzo ezibonisa izimbala. Indlela yesibili ayilindelekile futhi ihilela ukuhlaziywa kohlobo lwama-genome efuna i-ctDNA eveza umdlavuza. Ngaphandle kwalokho, ukulandelana kokulinganayo kuye kwasetshenziselwa indlela engabizi, engalindelekile. Impahla yizingxenye ze-DNA ezibhaliselwe ukwenza amaprotheni.
Ngezindlela ezihlosiwe, i-serum ihlaziywa ngokuguqulwa kwezakhi zofuzo eyaziwa ngeqoqo elincane lokuguqulwa komshayeli.
Izinguquko zomshayeli zibhekisela ekuguquleni kwezakhi zofuzo ezikhuthaza, noma "ukushayela," ukukhula kwamangqamuzana omdlavuza. Lezi zinguquko zifaka i- KRAS noma i- EGFR .
Ngenxa yentuthuko yezobuchwepheshe eminyakeni yamuva, izindlela ezihlosiwe zokuhlaziywa kwe-genome ngamanani amancane e-ctDNA ziye zafinyeleleka. Lezi buchwepheshe zifaka i-ARMS (uhlelo lokuvuselela ukuguqulwa kwenethiwekhi); i-PCR yedijithali (dPCR); ubuhlalu, emulsions, amplification, kanye magnetics (BEAMing); nokulandelana okujulile (CAPP-Seq).
Ngisho noma kube nentuthuko kwezobuchwepheshe eyenza indlela ehlosiwe ikwazi ukuyenza, indlela ehlosiwe ihlose kuphela izikhundla ezimbalwa zezinguquko (ama-hotspots) futhi ilahlekelwa eziningi zokuguqulwa komshayeli njengezifo zofuzo eziphefumulayo.
Inzuzo eyinhloko yezindlela ezingalindelekile ze-biopsy yetshezi ukuthi zingasetshenziswa kuzo zonke iziguli ngenxa yokuthi uvivinyo aluthembeki ekuguqulweni kwezakhi zofuzo eziphindaphindiwe. Izinguquko zezakhi zofuzo ezivame ukumboza zonke izinhlobo zamanqamu futhi azizona ezibhalwe ngumdlavuza. Noma kunjalo, le ndlela ayinakho ukuhlaziywa kwengqondo nokuhlaziya okuphelele kwe-genomes ye-tumor ayikakwenzeka.
Okuphawula, intengo yokulandelanisa i-genome yonke isuke ishiywe kakhulu. Ngonyaka ka-2006, intengo yokulandelela i-genome yonke yayingaba ngu-$ 300,000 (USD). Ngonyaka we-2017, izindleko zase ziye zafinyelela kuma-dollar ayi-1 000 (USD) nge-genome ngayinye, kufaka phakathi ama-reagents kanye nokuhlelwa kwemishini yokulandelana.
Umtholampilo we-Biopsy wamanzi
Imizamo yokuqala yokusebenzisa i-ctDNA yayiyi-diagnostic futhi iqhathaniswa namazinga eziguli ezinempilo nalabo abaneziguli zomdlavuza noma labo abanezinkinga ezibulalayo. Imiphumela yale mizamo yahlanganiswa, ngezifundo ezithile kuphela ezibonisa umehluko omkhulu obonisa umdlavuza, isimo esingenasifo, noma ukubuyela emuva.
Isizathu sokuthi i-ctDNA ingasetshenziswa kanjani kuphela isikhathi sokuthola umdlavuza ngoba izilinganiso eziguquguqukayo ze-ctDNA zitholakala emathunjini. Akuzona zonke izicubu "ezichitha" i-DNA enani elifanayo. Ngokuvamile, iziphambane eziphakeme kakhulu, izicubu ezandayo zachitha i-DNA engaphezu kokusakazwa kunalokho okwenzeka ekuqaleni, endaweni yangakini, izicubu. Ukwengeza, izinhlobo ezahlukene ze-tumor zenza imali ehlukahlukene ye-DNA ekusakazeni. Ingxenyana yokudlulisa i-DNA etholakala esithombeni ihlukahluka kakhulu kuzo zonke izifundo nezinhlobo zomdlavuza, kusuka ku-0.01% kuya ku-93%. Kubalulekile ukuphawula ukuthi, ngokujwayelekile, kuphela okuncane kwe-ctDNA esuselwa ku-tumor, konke okuvela kumathismu avamile.
Ukujikeleza i-DNA kungasetshenziswa njengesimemezelo sesifo. Ukujikeleza i-DNA kungasetshenziswa ukuqapha izinguquko zomdlavuza ngokuhamba kwesikhathi. Isibonelo, isifundo esisodwa sabonisa ukuthi isilinganiso seminyaka emibili yokusinda ezigulini ezinomdlavuza omncane (ie isibalo seziguli esasaphila okungenani iminyaka emibili emva kokuxilongwa ngomdlavuza omncane) kanti ukuguquguquka kwe- KRAS hotspot kwakungamaphesenti angu-100 kulabo abangenabo ubufakazi i-DNA ejikelezayo ehambelanayo. Ngaphezu kwalokho, kungenzeka ukuthi esikhathini esizayo esiseduze, ukujikeleza i-DNA kungasetshenziswa ukuqapha izilonda ezingenakuqapha.
Ukujikeleza i-DNA nakho kungasetshenziswa ukuqapha impendulo yokwelapha. Ngenxa yokuthi i-DNA ihambisa isithombe esihle kunawo wonke sezakhi zofuzo, le DNA cishe iqukethe i-DNA yokuxilonga, engasetshenziswa esikhundleni se-DNA yokuxilonga etholakala ezifweni ngokwazo.
Manje, ake sibheke ezinye izibonelo ezithile ze-biopsy yamanzi.
I-Guardant360
Impilo yokuqapha yaba nesimo esisebenzisa ukulandelana kwesizukulwane esilandelayo kwiphrofayli ejikeleza i-DNA yokuguqulwa kwemvelo kanye nokuhlelwa kabusha kwe-chromosomal kumagciwane angu-73 ahlobene nomdlavuza. I-Guardant Health yanyathelisa ucwaningo olubika ukusetshenziswa kwe-biopsy yamanzi ku-oncology. Ucwaningo lwalusebenzisa amasampula egazi kusuka ezigulini ezingu-15,000 ezinama-tumor angu-50 ahlanganisiwe.
Ngokwengxenye enkulu, imiphumela evela ekuhlolweni kwe-biopsy ye-liquid ehambisana nokuguqulwa kwesakhi zofuzo ezibhekwe kwi-biopsies ye-tumor.
Ngokusho kwe-NIH:
U-Guardant360 uhlonze ukuguqulwa okubucayi okufanayo ezigabeni ezibalulekile ezihlobene nomdlavuza efana ne- EGFR, i-BRAF, i- KRAS , ne- PIK3CA ngezikhathi ezifana kakhulu nalokho okwakubonwe ngaphambili kuma-sampuli e-tumor biopsy, okubalwa ngezibalo kuya ku-94% kuya ku-99%.
Ngaphezu kwalokho, ngokwe-NIH abacwaningi babika lokhu okulandelayo:
Esikhathini sesibili saleso sifundo, abacwaningi bahlola iziguli ezingaba ngu-400-iningi lazo lalinomdlavuza wamaphaphu noma umbala-owathola ukuthi i-ctDNA yegazi ne-tumor tissue tissue DNA iyatholakala futhi iqhathanisa amaphethini ezishintshayo zomzimba. Ukunemba okuphelele kwe-biopsy ye-liquid uma kuqhathaniswa nemiphumela evela kuhlaziyi ye-biopsy ye-tumor kwaba ngu-87%. Ukunemba kwanda ngo-98% lapho igazi ne-sampuli ze-tumor ziqoqiwe zingakapheli izinyanga ezingu-6 zomunye nomunye.
I-Guardant360 yayinembile ngisho noma amazinga okujikeleza i-DNA egazini ayephansi. Ngokuvamile, ukujikeleza i-DNA ye-tumor kwakha amaphesenti angu-0.4 e-DNA egazini.
Ngokubanzi, besebenzisa i-biopsy yamanzi, abacwaningi be-Guardant bakwazi ukuveza izimbangela zokulahla okungaqondisa ukwelashwa odokotela ngamaphesenti angu-67 eziguli. Lezi ziguli zazifanelekele ukwelashwa okugunyaziwe yi-FDA kanye nemithi yokwenza uphenyo.
i-ctDNA ne-Cancer Cancer
Ngo-2016, i-FDA ivume ukuhlolwa kokuguquguquka kwe-cogas EGFR ukuze isetshenziselwe ukutholakala kwezinguquko ze- EGFR ku-DNA ejikelezayo yezigulane zomdlavuza wamaphaphu. Lokhu kuhlolwa kwakuyi-biopsy ye-FDA evunyelwe yi-FDA kanye neziguli ezitholakale ezingaba ukhetho lwezokwelapha ngezinqubo zokwelashwa ezibhekiswe ku-erlotinib (i-Tarceva), i-afatinib (i-Gilotrif), ne-gefitinib (Iressa) njengokwelashwa kokuqala, ne-osimeritinib (i-Tagrisso) njenge ukwelashwa kwemigqa yesibili. Lezi zinhlobonhlobo ezithintekayo zokwelashwa kwamangqamuzana omdlavuza wezinguquko ezithile ze- EGFR .
Okubaluleke kakhulu, ngenxa yenani eliphakeme lemiphumela engamanga, i-FDA incoma ukuthi isampula ye-biopsy yesisindo nayo ithathwe isiguli esine-biopsy engalungile.
i-ctDNA ne-Cancer Cancer
Inani labantu ababulawa yisifo somdlavuza wesibindi selukhulile phakathi neminyaka engu-20 edlule. Njengamanje, umdlavuza wesibindi iyimbangela yesibili yokuhola komdlavuza emhlabeni jikelele. Awekho ama-biomarker amahle atholakalayo ukuthola nokuhlaziya isibindi, noma i-hepatocellular (HCC), umdlavuza. Ukujikeleza i-DNA kungaba yisimanga esihle se-cancer yesibindi.
Cabanga ngokucaphuna okulandelayo okuvela eLagbaa nabambhali abambisene nabo mayelana nokukwazi ukusebenzisa i-DNA ukuxilonga umdlavuza wesibindi:
I-Hypermethylation ye-RASSF1A, i-p15, ne-p16 iye yaphakanyiswa njengamathuluzi okuxilonga okuqala ekutadisheni okuphindaphindiwe kufaka phakathi iziguli ezingama-50 ze-HCC. Isignesha yama-gesi amane anesibindi (APC, GSTP1, RASSF1A, ne-SFRP1) nayo ihlolwe ngokunemba kokuxilongwa, kuyilapho i-methylation ye-RASSF1A ibikwa njenge-biomarker yokubikezela. Ucwaningo oluqhubekayo luhlolisise i-ctDNA kwiziguli ze-HCC ngokusebenzisa ubuchwepheshe bokulandelela obujulile .... Ngokudabukisayo, izinombolo ze-DNA ezikhohlisayo zitholakala ezinkambini ezimbili ze-HBV ngaphandle komlando wangaphambilini we-HCC ngesikhathi sokuqoqwa kwegazi, kodwa ngubani owahlakulela i-HCC ngesikhathi sokulandelwa. Lokhu kuthole kuvulwe umnyango wokuhlola ukukopishwa kwenombolo yekhophi ku-ctDNA njengethuluzi lokuhlola ukutholakala kwe-HCC yokuqala.
Izwi elivela
Ama-biopsies e-liquid ayindlela entsha ethokozisayo yokuxilongwa ngegazi. Njengamanje, ezinye ze-biopsies zamanzi, ezinikeza ukuprofiliswa okuphelele kwamangqamuzana, zitholakala odokotela ukuze baqinisekise ulwazi lwezofuzo olutholakala kumzimba we-biopsy. Kukhona futhi ama-biopsies amakhemikhali athile angasetshenziswa endaweni yezicubu ze-biopsy-uma ama-biopsies amathishu ayitholakali.
Kubalulekile ukukhumbula ukuthi izilingo eziningi ze-biopsy zamanzi ziqhubeka futhi ucwaningo oluningi ludingeka lwenziwa enyameni ngaphandle kosizo lwezokwelapha kulokhu kungenelela.
> Imithombo:
> Ukuhlolwa Kwegazi Ngezinguquko ZamaGenesis Ngezicubu Kubonisa Ithembiso Njengendlela Ehlukile Yokuthumba I-Biopsy. I-NIH.
> Heitzer E, Ulz P, Geigl JB. Ukujikeleza i-Tumor DNA njenge-Biopsy ye-Liquid for Cancer. I-Chemistry Clinical. 2015; 61: 112-123. doi: 10.1373 / clinchem.2014.222679
> I-Lagbaa J, i-Villanueva A. I-biopsy emanzini emdlavuza wesibindi. Ukuthola Imithi. 2015; 19 (105): 263-73.
> Ukuqubuka kwamanzi okuqukethe amanzi: Ukusebenzisa i-DNA egazini ukuthola, ukulandelela, nokuphatha ukwelashwa. I-NIH.
> Umetani N, et al. Inani eliphakeme le-DNA elijikelezayo mahhala kunensimu ye-plasma akubangelwa kakhulu yi-DNA engcolile ngesikhathi sokuhlukaniswa. Ann NY Acad Sci. 2006; 1075: 299-307.
> Wellstein A. Izimiso Ezijwayelekile kwi-Pharmacotherapy yeCanscer. Ku: Brunton LL, Hilal-Dandan R, Knollmann BC. ama-eds. Goodman & Gilman's: The Pharmacological Basis of Therapeutics, 13e eNew York, NY: McGraw-Hill.