KGN Cells — A Steroidogenic Human Granulosa-Like Tumor Cell Line for Reproductive and Endocrine Research

Introduction

The KGN cell line is a steroidogenic human ovarian granulosa-like tumor cell line widely used in reproductive biology, endocrinology, and ovarian cancer research. Established in 2001 by Nishi, Yanase, and colleagues, KGN was derived from a patient with invasive ovarian granulosa cell carcinoma and rapidly became one of the most valuable in vitro models for studying granulosa cell function, steroidogenesis, and the molecular mechanisms underlying conditions such as polycystic ovary syndrome (PCOS). The line retains key physiological characteristics of human granulosa cells, including functional follicle-stimulating hormone (FSH) receptor expression and measurable aromatase activity. These properties make KGN cells an indispensable tool for investigating hormonal regulation, ovarian folliculogenesis, insulin resistance, and the cellular responses to endocrine disruptors. Researchers around the world rely on KGN cells to model granulosa cell dysfunction, study mitochondrial biology, and screen candidate therapeutic compounds relevant to reproductive medicine.

Key Takeaways

• KGN is a human ovarian granulosa-like tumor cell line derived from an invasive granulosa cell carcinoma and characterized by steroidogenic activity.
• KGN cells express a functional FSH receptor and exhibit aromatase activity stimulable by FSH and cAMP.
• The line carries the hallmark FOXL2 p.Cys134Trp (c.402C>G) somatic mutation found in adult-type ovarian granulosa cell tumors.
• KGN cells are extensively used to model PCOS pathophysiology, granulosa cell apoptosis, mitochondrial dysfunction, and responses to endocrine disruptors.
• Viability after thawing exceeds 99%, and the line maintains stable growth characteristics across multiple passages.
• Comprehensive omics data — including proteomics, transcriptomics, whole exome sequencing, and drug screening datasets — are publicly available for KGN.

What is KGN?

KGN (Cellosaurus accession CVCL_0375) was derived from the ovarian granulosa cell layer of a 63-year-old female patient diagnosed with a malignant ovarian granulosa cell tumor. Nishi et al. established the line from a recurrence of the granulosa cell carcinoma following menopause, making it one of very few authenticated human granulosa-like cell lines available to researchers [1]. The line displays an abnormal karyotype of 45,XX, 7q-, -22 and carries the heterozygous FOXL2 p.Cys134Trp (c.402C>G) somatic mutation, a hallmark of adult-type ovarian granulosa cell tumors [2] [3]. Its population doubling time is approximately 46–47 hours. KGN cells are included in the COSMIC cell lines project and the Cancer Dependency Map (DepMap), and comprehensive omics datasets — covering DNA methylation, whole exome sequencing, proteomics, transcriptomics, SNP array analysis, and drug screening — are publicly available [4] [5] [6].

Cell Culture Information

KGN – Low confluency

KGN – High confluency

Advantages of KGN Cells

KGN cells offer a unique and well-validated in vitro platform that closely recapitulates human granulosa cell physiology. Unlike immortalized non-steroidogenic lines, KGN cells retain the capacity to secrete pregnenolone and progesterone, and their aromatase activity is further inducible by FSH and cyclic AMP stimulation [1]. This makes them particularly suitable for studying steroidogenesis, hormonal feedback mechanisms, and the biochemical pathways underlying ovarian follicle maturation. The presence of a functional FSH receptor distinguishes KGN from most other granulosa-like lines reviewed in the literature [7]. Their adherent, epithelial-like morphology also facilitates standard microscopy-based assays.

KGN cells demonstrate exceptional stability across multiple passages. Product specifications show viability exceeding 99% both after thawing and before freezing, with subcultivation viabilities consistently above 98% across five passages. This robustness supports reproducible long-term experimental programs. The line is part of major multi-omics initiatives, providing researchers with a rich backdrop of publicly available genomic, transcriptomic, and proteomic reference data [6] [8]. The heterozygous FOXL2 p.Cys134Trp mutation also makes KGN a genetically defined model for studying adult-type granulosa cell tumor biology [3].

Limitations of KGN Cells

Despite their many strengths, KGN cells carry important caveats that researchers must consider. As a tumor-derived line with an abnormal karyotype (45,XX, 7q-, -22), KGN cells may not fully replicate the behavior of normal, non-transformed primary granulosa cells. Their steroidogenic profile is incomplete: although they secrete pregnenolone and progesterone and display aromatase activity, they produce little or no 17α-hydroxylated steroids, dehydroepiandrosterone, androstenedione, or estradiol under basal culture conditions [1]. Researchers studying the full steroidogenic cascade should complement KGN experiments with primary cell or animal models.

Additionally, Imai et al. documented that KGN cells can undergo spontaneous phenotypic transformation at higher passages, acquiring a more invasive, metastasis-like character [9]. This passage-dependent behavioral shift means that careful passage tracking is essential to ensure experimental consistency. The relatively long population doubling time of approximately 46–47 hours also extends experimental timelines compared with faster-dividing lines. Furthermore, as a cell line of East Asian genetic ancestry, results should be interpreted with awareness of potential population-specific genetic variation [8].

Applications

PCOS and Granulosa Cell Dysfunction

KGN cells have become one of the most widely adopted in vitro tools for investigating the molecular basis of polycystic ovary syndrome (PCOS). Researchers routinely treat KGN cells with dihydrotestosterone (DHT), lipopolysaccharide (LPS), or free fatty acids to replicate the androgen excess and inflammatory environment characteristic of PCOS granulosa cells. Zhou et al. performed transcriptome sequencing of PCOS patient granulosa cells and used KGN cells to validate FN1 as a central hub gene regulating granulosa cell proliferation via PI3K-Akt, MAPK, and TGF-beta signaling pathways; FN1 knockdown in KGN cells significantly suppressed proliferation [10].

Multiple studies have leveraged KGN cells to dissect cell death pathways in PCOS. Cai et al. demonstrated that WTAP-mediated N6-methylation of TRAF6 promotes ferroptosis in KGN cells, linking m6A RNA modification to PCOS pathogenesis [11]. Zhang et al. used IFN-γ-treated KGN cells alongside patient-derived granulosa cells to show that AIM2-mediated PANoptosis — a convergent form of programmed cell death combining pyroptosis, apoptosis, and necroptosis — drives ovulatory dysfunction in PCOS [12]. Shen et al. further employed KGN cells to explore how hyperhomocysteinemia impairs granulosa cell function and reduces high-quality embryo rates in PCOS patients undergoing IVF/ICSI [13].

KGN cells have also served as a platform for testing candidate therapies. Zhang et al. showed that resveratrol alleviates PCOS-associated inflammation in LPS-treated KGN cells by suppressing AIM2 expression and reducing inflammatory cytokines including IL-6, IL-1β, MCP-1, and COX2 [14]. Lian et al. used KGN cells to validate that follicular fluid exosomal miR-143-5p targets RASAL2 to drive aberrant granulosa cell proliferation in PCOS, establishing an exosome-mediated communication axis relevant to ovulatory dysfunction [15]. Yao et al. employed DHT and free fatty acid-treated KGN cells as part of an integrative study identifying FCGBP as a shared molecular driver of PCOS-NAFLD comorbidity [16].

Endocrine Disruption and Environmental Toxicology

KGN cells are a well-established model for testing the granulosa cell-specific effects of environmental endocrine disruptors. Their functional FSH receptor and inducible aromatase activity make them especially sensitive indicators of compounds that interfere with estrogen biosynthesis. Studies have employed KGN cells to demonstrate that bisphenol A (BPA) induces apoptosis through GPER-dependent activation of the ROS/Ca²⁺-ASK1-JNK pathway, establishing a mechanistic link between a ubiquitous plasticizer and granulosa cell death [25]. Similarly, bisphenol AF (BPAF) was shown to induce concentration-dependent KGN cell apoptosis via estrogen receptor beta (ERβ) and the ROS-ASK1-JNK MAPK cascade, highlighting the sensitivity of granulosa cells to structurally related bisphenol analogues[26].

KGN cells have also been used to assess the reproductive toxicity of novel nanomaterials. Liang et al. demonstrated that sulfur quantum dots (SQDs) — heavy metal-free nanomaterials with broad industrial applications — cause ferroptosis in both human placental trophoblast and KGN ovarian granulosa cells, and induce adverse pregnancy outcomes in mice [17]. This study established KGN cells as a critical human cellular readout in a multi-level toxicological framework spanning molecular, cellular, and whole-organism endpoints. The consistent sensitivity of KGN cells to oxidative stress-inducing agents across multiple chemical classes underlines their value in reproductive toxicology screening programs.

Mitochondrial Biology and Ovarian Aging

An emerging body of research uses KGN cells to study the mitochondrial mechanisms underlying granulosa cell senescence and ovarian aging. Shim et al. investigated whether prostaglandin D2 (PGD2) could restore ovarian competence through coordinated mitochondrial remodeling, using KGN cells alongside primary ovarian cells from aged mice and preimplantation embryos. PGD2 enhanced KGN cell viability, attenuated senescence-associated β-galactosidase activity, restored mitochondrial network integrity, increased mitochondrial membrane potential, and elevated ATP production [18]. These findings position PGD2 as a candidate mediator of mitochondrial quality control in aging granulosa cells.

Teng et al. explored how gap junction communication mediated by connexin 43 (CX43) becomes disrupted during ovarian aging and used KGN cells to validate the mechanistic action of the peptide ZP123 in restoring CX43-mediated coupling [19]. Zhu et al. employed KGN cells and a cyclophosphamide-induced diminished ovarian reserve mouse model to demonstrate that Qilin Pills protect granulosa cells by suppressing pathological overactivation of PINK1/Parkin-mediated mitophagy [20]. These studies collectively demonstrate that KGN cells provide a tractable human cellular model for dissecting mitophagy, membrane potential dynamics, and other mitochondrial parameters relevant to female reproductive aging.

Birkebæk et al. used KGN cells to evaluate how N-carbamoyl-L-glutamate (NCG), an analogue of the allosteric activator of mitochondrial CPS1, influences granulosa cell proliferation, arginine levels, and mTORC1 signaling during follicle activation [21]. Shin et al. used KGN cells as part of a broader study examining whether placental growth factor (PlGF) secreted by placenta-derived mesenchymal stem cells protects ovarian granulosa cells from oxidative injury, demonstrating antioxidant and cytoprotective effects relevant to ovarian insufficiency [22].

Granulosa Cell Tumor Biology and Oncology

As a cell line derived directly from an invasive granulosa cell carcinoma, KGN serves as a primary model for understanding the molecular biology of ovarian granulosa cell tumors (GCTs). The landmark establishment paper by Nishi et al. described the founding characteristics of the line in detail: KGN had a population doubling time of approximately 46.4 hours, an abnormal karyotype, and a steroidogenic profile consistent with granulosa cell differentiation [1]. Crucially, Nishi et al. demonstrated that KGN cells expressed a functional FSH receptor and showed stimulable aromatase activity, making the line a physiologically relevant model for both tumor biology and normal granulosa cell endocrinology [1].

Subsequent work confirmed that the FOXL2 c.402C>G mutation — present in the vast majority of adult-type GCTs — is also carried by KGN cells, providing genetic validation of its tumor origin [2] [3]. Imai et al. characterized the unique capacity of KGN cells to spontaneously transform into a more aggressive, invasive phenotype at higher passages, establishing the line as a model for studying GCT progression and metastasis [9]. Jiang et al. used CRISPR/Cas9 to knock out filamin A (FLNA) in KGN cells, revealing that FLNA regulates proliferation, cell cycle progression, migration, and cytoskeletal organization under mechanical stress, with implications for GCT tumor growth [23].

At the pan-cancer level, KGN cells have contributed to large-scale pharmacogenomics and proteomics studies. Iorio et al. included KGN in a landscape analysis of pharmacogenomic interactions across 1,001 cancer cell lines, mapping cancer-driven alterations to drug sensitivity profiles [5]. Gonçalves et al. incorporated KGN in a pan-cancer proteomic map of 949 human cell lines, quantifying 8,498 proteins and integrating multi-omics data with drug response and CRISPR-Cas9 gene essentiality screens [6]. These large-scale datasets enhance the utility of KGN cells well beyond reproductive biology.

Steroidogenesis and Hormonal Signaling

KGN cells retain a steroidogenic capacity that makes them suitable for studying the hormonal signaling pathways governing folliculogenesis and ovarian endocrine function. Havelock et al. reviewed the utility of granulosa cell lines including KGN and highlighted the importance of FSH receptor expression and aromatase activity as defining functional characteristics for modeling granulosa cell biology [7]. KGN cells have been used to study how phytochemicals modulate steroidogenesis in PCOS. Ikrar et al. employed an integrative approach combining transcriptomics, metabolomics, network pharmacology, and KGN-based in vitro validation to show that compounds from Cinnamomum burmannii and Myristica fragrans can modulate steroidogenic and insulin signaling pathways in PCOS-relevant contexts [24].

KGN cells have also been used to study the interface between steroidogenesis and programmed cell death. The line is responsive to androgen excess: salidroside was shown to alleviate DHT-induced oxidative stress and apoptosis in KGN cells via the AMPK/Nrf2 pathway, demonstrating KGN's utility for evaluating cytoprotective agents in hyperandrogenic environments [27]. Arachidonic acid enriched in the follicular fluid of PCOS patients was shown to induce oxidative stress and upregulate GDF15 expression in KGN cells, linking lipid mediators in the follicular microenvironment to granulosa cell dysfunction [28]. Together, these studies illustrate how KGN cells bridge steroidogenic, metabolic, and stress-response signaling in a single human in vitro system.

Conclusion

KGN cells occupy a unique and indispensable position in reproductive biology and ovarian endocrinology. Since their establishment and characterization by Nishi et al. in 2001, the line has become the most widely used human granulosa-like cell model for investigating PCOS pathophysiology, granulosa cell apoptosis and programmed cell death, steroidogenesis, mitochondrial dysfunction, and the reproductive toxicity of endocrine disruptors. The retention of a functional FSH receptor, stimulable aromatase activity, and the hallmark FOXL2 p.Cys134Trp mutation gives KGN cells exceptional physiological and genetic relevance. Their outstanding viability characteristics — consistently above 98% across passages — combined with rich publicly available multi-omics datasets make them a highly practical and well-supported research tool. Whether your work focuses on polycystic ovary syndrome, ovarian granulosa cell tumor biology, mitophagy, insulin resistance, or the effects of environmental compounds on ovarian function, KGN Cells provide a robust and reproducible human cellular platform. Visit cytion.com to explore full product specifications, view authentication data, and order KGN cells for your research program.

Key Publications

1. Nishi Y, Yanase T, Mu Y (2001) Establishment and characterization of a steroidogenic human granulosa-like tumor cell line, KGN, that expresses functional follicle-stimulating hormone receptor. Endocrinology. PMID: 11145608
2. Schrader KA, Gorbatcheva B, Senz J (2009) The specificity of the FOXL2 c.402C>G somatic mutation: a survey of solid tumors. PloS one. PMID: 19956657
3. Benayoun BA, Caburet S, Dipietromaria A (2010) Functional exploration of the adult ovarian granulosa cell tumor-associated somatic FOXL2 mutation p.Cys134Trp (c.402C>G). PloS one. PMID: 20098707
4. Bignell GR, Greenman CD, Davies H (2010) Signatures of mutation and selection in the cancer genome. Nature. PMID: 20164919
5. Iorio F, Knijnenburg TA, Vis DJ (2016) A Landscape of Pharmacogenomic Interactions in Cancer. Cell. PMID: 27397505
6. Gonçalves E, Poulos RC, Cai Z (2022) Pan-cancer proteomic map of 949 human cell lines. Cancer cell. PMID: 35839778
7. Havelock JC, Rainey WE, Carr BR (2004) Ovarian granulosa cell lines. Molecular and cellular endocrinology. PMID: 15541573
8. Dutil J, Chen Z, Monteiro AN (2019) An Interactive Resource to Probe Genetic Diversity and Estimated Ancestry in Cancer Cell Lines. Cancer research. PMID: 30894373
9. Imai M, Muraki M, Takamatsu K (2008) Spontaneous transformation of human granulosa cell tumours into an aggressive phenotype: a metastasis model cell line. BMC cancer. PMID: 18980698
10. Zhou K, Han W, Wang Q (2026) Transcriptome screening and functional validation of FN1 in the regulation of granulosa cell proliferation in polycystic ovary syndrome. The Korean journal of physiology & pharmacology. PMID: 42027048
11. Cai Z, Liu R, Zhao L (2026) WTAP-mediated N6-methylation of TRAF6 Facilitates Polycystic Ovary Syndrome by Inducing Ferroptosis. Reproductive sciences. PMID: 42115577
12. Zhang Q, Meng Y, Zhao W (2026) IFN-γ-induced AIM2-PANoptosis in granulosa cells leads to ovulatory dysfunction in polycystic ovary syndrome. Biochemical pharmacology. PMID: 42114679
13. Shen H, Jia T, Luo X (2026) Hyperhomocysteinemia reduces the high-quality embryo rate in PCOS patients undergoing IVF/ICSI: clinical evidence and a preliminary exploration of mechanisms in KGN cells. Journal of ovarian research. PMID: 42129831
14. Zhang Q, Li H, Meng Y (2026) Resveratrol Alleviates Inflammation in Polycystic Ovary Syndrome by Inhibiting Absent in Melanoma 2 Expression. Phytotherapy research. PMID: 42118129
15. Lian Y, Chen J, Zhang T (2026) A novel role of follicular fluid exosomal miR-143-5p in polycystic ovary syndrome: targeting RASAL2 to drive granulosa cell proliferation. Molecular and cellular endocrinology. PMID: 42208847
16. Yao Y, Si M, Ding H (2026) FCGBP links hormonal imbalance and hepatic steatosis in PCOS-NAFLD comorbidity: an integrative bioinformatics and experimental study. Frontiers in endocrinology. PMID: 42232754
17. Liang Y, Zhang W, Sun Y (2026) Sulfur quantum dots cause ferroptosis in human placental trophoblast and ovarian granulosa cells and induce mouse adverse pregnancy outcomes. Environment international. PMID: 42019120
18. Shim YH, An JY, Ryu JS (2026) Prostaglandin D2 reinforces mitochondrial quality control to enhance ovarian and embryonic competence. Biomedicine & pharmacotherapy. PMID: 42176571
19. Teng H, Xie Q, Zhou C (2026) Intraperitoneal ZP123 improves aged oocyte quality by restoring granulosa cell gap junctions and improving mitochondrial function. Journal of ovarian research. PMID: 42174667
20. Zhu F, Hu C, Huang S (2026) Qilin Pills protect against diminished ovarian reserve by suppressing pathological overactivation of PINK1/Parkin-mediated mitophagy in granulosa cells. Journal of ethnopharmacology. PMID: 42167661
21. Birkebæk SB, Amoushahi M, Lykke-Hartmann K (2026) Activation of mitochondrial CPS1 promotes dormant ovarian follicle activation via arginine elevation and the mTORC1 pathway. Frontiers in cell and developmental biology. PMID: 42111264
22. Shin JY, Lee DH, Park H (2026) Placental Growth Factor Secreted from Placenta-Derived Mesenchymal Stem Cells Improves Ovarian Function in TAA-Injured Rats via Antioxidant Effects. Antioxidants. PMID: 42193225
23. Jiang Y, Caban KM, Peitzsch M (2026) Knockout of filamin A in KGN granulosa tumor cells impairs proliferation, cell cycle progression, migration, and cytoskeletal organization under mechanical stress. Biological research. PMID: 42163310
24. Ikrar T, Siahaan SC, Hendarto H (2026) Multi-Target Modulation of Metabolic and Steroidogenic Pathways by Cinnamomum burmannii and Myristica fragrans in Polycystic Ovary Syndrome. Nutrients. PMID: 42075118
25. Huang M, Huang M, Li X, Liu S, Fu L, Jiang X, Yang M (2021) Bisphenol A induces apoptosis through GPER-dependent activation of the ROS/Ca²⁺-ASK1-JNK pathway in human granulosa cell line KGN. Ecotoxicology and Environmental Safety. PMID: 33039870
26. Huang M, Li X, Jia S, Liu S, Fu L, Jiang X, Yang M (2021) Bisphenol AF induces apoptosis via estrogen receptor beta (ERβ) and ROS-ASK1-JNK MAPK pathway in human granulosa cell line KGN. Environmental Pollution. PMID: 33189448
27. Ji R, Jia FY, Chen X, Wang ZH, Jin WY, Yang J (2022) Salidroside alleviates oxidative stress and apoptosis via AMPK/Nrf2 pathway in DHT-induced human granulosa cell line KGN. Archives of Biochemistry and Biophysics. PMID: 34813774
28. Ma Y, Zheng L, Wang Y, Gao Y, Xu Y (2022) Arachidonic acid in follicular fluid of PCOS induces oxidative stress in a human ovarian granulosa tumor cell line (KGN) and upregulates GDF15 expression as a response. Frontiers in Endocrinology. PMID: 35634503