Endometriosis-Associated Ovarian Carcinomas: How PI3K/AKT/mTOR Pathway Affects Their Pathogenesis

Endometriosis-associated ovarian cancer: a different clinical entity

OBJECTIVE

To compare survival outcomes and patterns of recurrence between endometriosis-associated ovarian cancer patients and non-endometriosis-associated ovarian cancer patients.

METHODS

This retrospective study included data of consecutive patients with endometrioid or clear cell ovarian cancer treated at the Fondazione IRCCS Istituto Nazionale dei Tumori di Milano between January 2010 and June 2021. Patients were assigned to one of two groups according to the absence or presence of endometriosis together with ovarian cancer at final histological examination. Survival outcomes were assessed using Kaplan-Meier and Cox hazard models. Proportions in recurrence rate and pattern of recurrence were evaluated using the Fisher exact test.

RESULTS

Overall, 83 women were included in the endometriosis-associated ovarian cancer group and 144 in the non-endometriosis-associated ovarian cancer group, respectively. Patients included in the non- endometriosis-associated ovarian cancer group had a shorter disease-free survival than those in the endometriosis-associated ovarian cancer group (23.4 (range 2.0-168.9) vs 60.9 (range 4.0-287.8) months; p<0.001). Univariable and multivariable analyses showed that the association with endometriosis, previous hormonal treatment, early stage at presentation, and endometrioid histology were related to better disease-free survival in the entire study population. Similarly, patients in the non-endometriosis-associated ovarian cancer group had a shorter median (range) overall survival than those in the endometriosis-associated ovarian cancer group (54.4 (range 0.7-190.6) vs 77.6 (range 4.5-317.8) months; p<0.001). Univariable and multivariable analyses showed that younger age at diagnosis, association with endometriosis, and early stage at presentation were related to better overall survival. The recurrence rate was higher in the non-endometriosis-associated ovarian cancer group (63/144 women, 43.8%) than in the endometriosis-associated ovarian cancer group (17/83 women, 20.5%; p<0.001).

CONCLUSIONS

Endometriosis-associated ovarian cancer patients had significantly longer disease-free survival and overall survival than non-endometriosis-associated ovarian cancer patients, while the recurrence rate was higher in non-endometriosis-associated ovarian cancer patients.

A large deletion in TSC2 causes tuberous sclerosis complex by dysregulating PI3K/AKT/mTOR signaling pathway

BACKGROUND/AIM

Tuberous sclerosis complex (TSC) is a multi-system syndrome caused by loss-of-function mutation in TSC1 or TSC2. Most TSC patients present with cardiac rhabdomyoma or cortical tubers during fetal life, and the symptoms are not uniform as their age. The gene products of TSC1/2 are components of the TSC protein complex and are important role in the PI3K/AKT/mTOR (PAM) signaling pathway. Based on three members of a family with variable expressivity, the purpose of this study was to clarify the clinical features of TSC in different age groups and to analyze the genetic characteristics of TSC2 gene.

METHODS

Clinical exome sequencing and co-segregation were used to identify a three-generation family with four affected individuals. HEK-293T cell model was constructed for subsequent experiments. Quantitative RT-PCR, western blotting, and subcellular localization were used to analyze the expression effect of TSC2 mutation. CCK-8 assay, wound healing assay, and cell cycle analysis were used to analyze the function effect of TSC2 mutation.

RESULT

We identified a TSC family with heterozygous deletion of exon 4 in TSC2 by clinical exon sequencing. Sanger sequencing indicated that the affected individuals have 2541-bp deletion that encompassed exon 4 and adjacent introns. Deletion of exon 4 decreased the TSC2 mRNA and protein levels in HEK-293T cells, and activated the PI3K/AKT/mTOR pathway, thereby altering the cell cycle and promoting cell proliferation and migration.

CONCLUSION

We confirmed the pathogenicity of the large deletion in TSC2 in a three- generations family.. Deletion of exon 4 of TSC2 affected cell proliferation, migration, and cell cycle via abnormal activation of the PAM pathway. This study evaluated the pathogenic effect of deletion of exon 4 of TSC2 and investigated the underlying mechanism.

The mysterious association between adiponectin and endometriosis

Adiponectin is a pleiotropic cytokine predominantly derived from adipose tissue. In addition to its role in regulating energy metabolism, adiponectin may also be related to estrogen-dependent diseases, and many studies have confirmed its involvement in mediating diverse biological processes, including apoptosis, autophagy, inflammation, angiogenesis, and fibrosis, all of which are related to the pathogenesis of endometriosis. Although many researchers have reported low levels of adiponectin in patients with endometriosis and suggested that it may serve as a protective factor against the development of the disease. Therefore, the purpose of this review was to provide an up-to-date summary of the roles of adiponectin and its downstream cytokines and signaling pathways in the aforementioned biological processes. Further systematic studies on the molecular and cellular mechanisms of action of adiponectin may provide novel insights into the pathophysiology of endometriosis as well as potential therapeutic targets.

Endometriosis-Associated Ovarian Cancer: From Molecular Pathologies to Clinical Relevance

Endometriosis is a chronic condition affecting reproductive-aged women, characterized by the growth of ectopic endometrial tissue. Despite being benign, endometriosis is associated with an increased risk of certain cancers, including endometriosis-associated ovarian cancer (EAOC). Ovarian cancer is rare, but more common in women with endometriosis, particularly endometrioid and clear-cell carcinomas. Factors such as hormonal imbalance, reproductive history, environmental exposures, and genetic predisposition contribute to the malignant transformation of endometriosis. Thus, understanding potential risk factors causing malignancy is crucial. Over the past few decades, various genetic mutations, microRNAs, as well as tumor microenvironmental factors have been identified, impacting pathways like PI3K/AKT/mTOR, DNA repair mechanisms, oxidative stress, and inflammation. Thus, this review aims to summarize molecular studies involved in EAOC pathogenesis as potential therapeutic targets. However, further research is needed to better understand the molecular and environmental factors driving EAOC development, to target the susceptibility of endometriotic lesions to malignant progression, and to identify effective therapeutic strategies.

Focusing on the role of protein kinase mTOR in endometrial physiology and pathology: insights for therapeutic interventions

The mammalian target of rapamycin (mTOR) is a serine/threonine protein kinase crucial for cellular differentiation, proliferation, and autophagy. It shows a complex role in the endometrium, influencing both normal and pathogenic conditions. mTOR promotes the growth and maturation of endometrial cells, enhancing endometrial receptivity and decidualization. However, it also contributes to the development of endometriosis (EMs) and endometrial cancer (EC), thus emerging as a therapeutic target for these conditions. In this review, we summarize recent research progress on the mTOR signalling pathway in the endometrium. This provides insights into female endometrial structure and function and guides the prevention and treatment of related diseases.

Refractory ovarian squamous cell carcinoma arising from a seromucinous borderline tumor with squamous overgrowth: A case report

Ovarian squamous cell carcinoma (SCC) is rare, and most cases arise from ovarian teratomas. Herein, we present a case of ovarian SCC arising from an ovarian seromucinous borderline tumor (SMBT) with squamous overgrowth. A 71-year-old woman an underwent emergency laparotomy due to the rupture of a right ovarian tumor suspected to be a borderline or malignant tumor. We performed a total abdominal hysterectomy, bilateral salpingo-oophorectomy, and partial omentectomy. The postoperative diagnosis was stage IC3 ovarian SCC arising from the SMBT with a squamous overgrowth. Subsequently, she underwent six cycles of combination therapy comprising paclitaxel and carboplatin. Two months after the last chemotherapy treatment, she presented with back pain. A CT scan showed a 14 mm pelvic tumor affecting the ureter, leading to right hydronephrosis. The patient underwent tumor resection and ureteroureterostomy. The pathological diagnosis was keratinizing SCC, representing ovarian cancer recurrence. Eight months after the removal of the recurrent tumor, we found a 35 mm recurrent pelvic tumor causing right hydronephrosis. Additionally, a 20 mm pleural dissemination was identified. Comprehensive genome profiling of recurrent tumor revealed genomic abnormalities in TP53, ARID1A, PTEN, PIK3R1, and CDKN2A/2B. Regarding immunotherapy biomarkers, the microsatellite instability test result was negative, the tumor mutation burden was low, and PD-L1 was highly expressed. The patient was referred to another hospital for participation in an immunotherapy clinical trial for ovarian SCC. This case indicates that refractory ovarian SCC can arise from SMBT. Further evaluation of additional cases is required to identify the molecular biological characteristics of ovarian SCC.

Elucidating the role of Brain-Derived Neurotrophic Factor (BDNF) and its receptor Tyrosine Receptor Kinase B (TrkB) in the development and symptoms of endometriosis

Endometriosis (EMs) is a common disease among women of reproductive age, and as of now, the clinical understanding of the etiology of this disease remains unclear. The occurrence of EMs has a profound impact on the reproductive health of women, making early diagnosis and treatment of this disease a pressing challenge in clinical practice. Recent studies have found that Brain-Derived Neurotrophic Factor (BDNF), in combination with its high-affinity receptor Tyrosine Receptor Kinase B (TrkB), participates in the development of EMs and the appearance of clinically relevant symptoms by activating the Mitogen-Activated Protein Kinase (MAPK) pathway, the Phosphatidylinositol 3-Kinase/Protein Kinase B (PI3K/AKT) pathway, and the Phospholipase C-gamma (PLCγ) signaling pathway, or by interacting with other factors. In order to gain a deeper understanding of the pathogenesis related to EMs, this article reviews the roles of BDNF and TrkB in EMs, particularly in terms of aberrant apoptosis and autophagy, cell invasion, proliferation, angiogenesis, oxidative stress, and inflammatory reactions, as well as their relationship with the symptoms associated with EMs.