Vloga transkripcijskega dejavnika NANOG pri razvoju karcinoma materničnega vratu

Koren, Miha (author), Strojan Fležar, Margareta (mentor), Poljak, Mario (comentor)

Ploščatocelični karcinom materničnega vratu (PKMV) se razvije preko več stopenj predrakavih sprememb ploščatih celic materničnega vratu (MV) in je večinoma povezan z okužbo s človeškimi papilomavirusi (HPV, angl. human papillomaviruses). Predrakave spremembe ploščatega epitelija MV delimo v ploščatocelične intraepitelijske lezije nizke stopnje (PIL-NS) in ploščatocelične intraepitelijske lezije visoke stopnje (PIL-VS). PIL-VS razdelimo v cervikalno intraepitelijsko lezijo stopnje 2 in stopnje 3 (CIN 2 in CIN 3). Raziskave na področju PKMV so potrdile obstoj tumorskih matičnih celic (TMC) in izražanje označevalcev TMC, med drugim izražanje transkripcijskih dejavnikov NANOG, SOX2 in OCT3/4. V nalogi smo raziskali vlogo in regulacijo NANOG na beljakovinskem, RNA in DNA nivoju v karcinogenezi PKMV ter njegov diagnostični pomen. V raziskavo smo vključili 40 tkivnih vzorcev PIL/CIN in PKMV s priležnim nedisplastičnim ploščatim epitelijem MV (kontrole, K), skupno 40 bolnic oziroma 80 tkivnih vzorcev. Uporabili smo imunohistokemične metode, genotipizacijo HPV, kvantitativno verižno reakcijo s polimerazo in sekvenciranje po Sangerju. Beljakovini NANOG in SOX2 sta bili bolj izraženi v PIL/CIN in PKMV kot v K, njuno izražanje je naraščalo s stopnjo v karcinogenezi PKMV. Pri vseh bolnicah smo potrdili okužbo s HPV. Gen NANOG je bil najbolj izražen v PKMV. Regulatorja OCT3/4 in RoR sta pokazala pozitivno korelacijo z izražanjem NANOG, miR-145 pa negativno korelacijo. Spremenjene metilacije promotorja NANOG nismo zaznali. Naši rezultati kažejo višje izražanje beljakovin NANOG in SOX2 v PIL/CIN kot v K in v PIL-VS kot v PIL-NS. Višje izražanje beljakovine SOX2 smo ugotovili v PIL-VS/CIN 3 kot v PIL-VS/CIN 2. Izražanje NANOG mRNA se je v karcinogenezi razlikovalo od izražanja beljakovine NANOG, kar kaže na vlogo regulacije na posttranskripcijskem nivoju, med drugim z miR-145 in RoR, poleg regulacije z beljakovinami. Prispevali smo nova spoznanja o vlogi regulatorjev NANOG v karcinogenezi PKMV in potrdili možnost uporabe NANOG in SOX2 kot dodatnih označevalcev v diagnostiki PIL/CIN.

• Language: Slovenian
• Keywords: ploščatocelični karcinom materničnega vratu, ploščatocelična intraepitelijska lezija, cervikalna intraepitelijska neoplazija, tumorske matične celice, NANOG
• Work type: Doctoral dissertation
• Organization: MF - Faculty of Medicine
• Year: 2025
• PID: 20.500.12556/RUL-175973
• Publication date in RUL: 16.11.2025

Secondary language

• Language: English
• Title: The role of NANOG in the development of cervical carcinoma

Abstract

The majority of cervical squamous cell carcinomas (CSCCs) are associated with human papillomaviruses infection and develop from precursor lesions of the squamous cervical epithelium (SCE). Precursor lesions of the SCE are divided into low-grade squamous intraepithelial lesions (LSILs) and high-grade squamous intraepithelial lesions (HSILs). HSILs may be further subdivided into HSIL/cervical intraepithelial neoplasia (CIN), grade 2 (CIN 2) and HSIL/CIN, grade 3 (CIN 3). Recent studies on CSCC have suggested that tumorigenesis depends on cancer stem cells (CSCs). CSCs express several markers, NANOG, OCT3/4, and SOX2 among the others. We analysed expression and diagnostic significance of NANOG and its regulation on protein, RNA and DNA levels in cervical squamous carcinogenesis. Our study included 40 biopsy tissue samples from patients with CSCCs and SILs/CINs and their adjacent non-dysplastic SCE. Immunohistochemistry, HPV genotyping, quantitative polymerase chain reaction and Sanger sequencing were used. NANOG and SOX2 immunohistochemical expression gradually increased from non-dysplastic SCE via LSIL and HSIL to CSCC. HPV infection was confirmed in all 40 included patients. At mRNA level, NANOG was maximally expressed in CSCCs. Regulators OCT3/4 and RoR correlated positively with expression of NANOG, while miR-145 was negatively correlated with expression of NANOG. NANOG promoter methylation was not changed. Our results showed higher expression of proteins NANOG and SOX2 in LSIL compared to nondysplastic SCE and lower compared to HSIL. HSIL/CIN 3 showed higher immunohistochemical expression of SOX2 than HSIL/CIN 2. The expression of NANOG mRNA was different from the expression of NANOG protein, indicating an important role of post-transcription regulation, with miR-145 and RoR as the key regulatory mechanisms beside protein regulators in cervical squamous carcinogenesis. Our results contributed new insights into the role of NANOG regulators in the cervical squamous carcinogenesis. We also confirmed a potential of NANOG and SOX2 as additional diagnostic markers for classifying SILs/CINs.

• Keywords: cervical squamous cell carcinoma, squamous intraepithelial lesion, cervical intraepithelial neoplasia, cancer stem cell, NANOG