Targeted therapies for rare gynaecological cancers

Recent development of nanotechnology-based approaches for gynecologic cancer therapy

Gynecological cancer is a life-threatening malignancy among women. Traditional therapies, including chemotherapy, often face challenges in terms of chemotherapeutic drug solubility and resistance, specificity, tumor site targeting, and toxicity to healthy tissues, leading to shortened efficacy and unfavorable patient outcomes and survival rates in patients with gynecologic malignancies. Recently, nanotechnology-based therapeutic methods such as targeted drug delivery and phototherapies have emerged as an appropriate alternative to overcome issues associated with traditional therapeutic methods. Specifically, nanomaterials and nanomaterial-based methods enhance the delivery of therapeutic/targeting agents to tumor sites and cellular uptakes and improve the tumor-suppressing effect. This review aims to provide an overview and future perspective on the potential impact of nanotechnology-based therapeutic methods for effective therapies for gynecologic cancer.

Neuroendocrine Neoplasms of the Gynecologic Tract

Simple Summary

Neuroendocrine refers to the cells that synthesize and secrete messenger chemicals such as neuropeptides and amines. Neuroendocrine neoplasms (NENs) are aggressive tumors arising from neuroendocrine cells, with an annual incidence of 6.98/100,000 and a prevalence of 170,000 in the United States. Primary gynecologic NENs constitute ≤2% of female reproductive tumors. NENs of the gynecologic tract are associated with high recurrence rates and dismal prognosis, making their treatment challenging. This article focuses on the updated staging classifications, clinicopathological characteristics, imaging, and management of NENs of the gynecological tract.

Abstract

Gynecological tract neuroendocrine neoplasms (NEN) are rare, aggressive tumors from endocrine cells derived from the neuroectoderm, neural crest, and endoderm. The primary gynecologic NENs constitute 2% of gynecologic malignancies, and the cervix is the most common site of NEN in the gynecologic tract. The updated WHO classification of gynecologic NEN is based on the Ki-67 index, mitotic index, and tumor characteristics such as necrosis, and brings more uniformity in the terminology of NENs like other disease sites. Imaging plays a crucial role in the staging, triaging, restaging, and surveillance of NENs. The expression of the somatostatin receptors on the surface of neuroendocrine cells forms the basis of increasing evaluation with functional imaging modalities using traditional and new tracers, including ⁶⁸Ga-DOTA-Somatostatin Analog-PET/CT. Management of NENs involves a multidisciplinary approach. New targeted therapies could improve the paradigm of care for these rare malignancies. This article focuses on the updated staging classifications, clinicopathological characteristics, imaging, and management of gynecologic NENs of the cervix, ovary, endometrium, vagina, and vulva, emphasizing the relatively common cervical neuroendocrine carcinomas among these entities.

The Role of Omics Approaches to Characterize Molecular Mechanisms of Rare Ovarian Cancers: Recent Advances and Future Perspectives

Rare ovarian cancers are ovarian cancers with an annual incidence of less than 6 cases per 100,000 women. They generally have a poor prognosis due to being delayed diagnosis and treatment. Exploration of molecular mechanisms in these cancers has been challenging due to their rarity and research efforts being fragmented across the world. Omics approaches can provide detailed molecular snapshots of the underlying mechanisms of these cancers. Omics approaches, including genomics, transcriptomics, proteomics, and metabolomics, can identify potential candidate biomarkers for diagnosis, prognosis, and screening of rare gynecological cancers and can aid in identifying therapeutic targets. The integration of multiple omics techniques using approaches such as proteogenomics can provide a detailed understanding of the molecular mechanisms of carcinogenesis and cancer progression. Further, omics approaches can provide clues towards developing immunotherapies, cancer recurrence, and drug resistance in tumors; and form a platform for personalized medicine. The current review focuses on the application of omics approaches and integrative biology to gain a better understanding of rare ovarian cancers.

(In)Distinctive Role of Long Non-Coding RNAs in Common and Rare Ovarian Cancers

Rare ovarian cancers (ROCs) are OCs with an annual incidence of fewer than 6 cases per 100,000 women. They affect women of all ages, but due to their low incidence and the potential clinical inexperience in management, there can be a delay in diagnosis, leading to a poor prognosis. The underlying causes for these tumors are varied, but generally, the tumors arise due to alterations in gene/protein expression in cellular processes that regulate normal proliferation and its checkpoints. Dysregulation of the cellular processes that lead to cancer includes gene mutations, epimutations, non-coding RNA (ncRNA) regulation, posttranscriptional and posttranslational modifications. Long non-coding RNA (lncRNA) are defined as transcribed RNA molecules, more than 200 nucleotides in length which are not translated into proteins. They regulate gene expression through several mechanisms and therefore add another level of complexity to the regulatory mechanisms affecting tumor development. Since few studies have been performed on ROCs, in this review we summarize the mechanisms of action of lncRNA in OC, with an emphasis on ROCs.

The puzzle of gynecologic neuroendocrine carcinomas: State of the art and future directions

Primary gynecologic neuroendocrine carcinomas (gNECs) are a heterogeneous spectrum of rare and highly aggressive neoplasms, accounting for about 2% of all gynecologic malignancies, which mostly resemble the small cell lung carcinoma (SCLC). Due to the lack of standardized treatment guidelines, their management poses a noteworthy clinical challenge. Currently, cumulative data retrieved from the management of SCLC and from retrospective studies supports a multimodality strategy, based on surgery, chemotherapy, and radiotherapy. Nevertheless, the prognosis remains poor and recurrences are extremely frequent. Hence, there is an urgent need for novel treatment options and promising molecular targets. Recently, there has been an increasing interest on the potential role of immune checkpoint inhibitors, especially in the recurrent setting. However, only scant evidence exists and there is still a long road ahead. A solid collaboration between gynecologists and oncologists worldwide is required to improve the treatment of these puzzling tumors.

Could MicroRNAs Be Useful Tools to Improve the Diagnosis and Treatment of Rare Gynecological Cancers? A Brief Overview

Gynecological cancers pose an important public health issue, with a high incidence among women of all ages. Gynecological cancers such as malignant germ-cell tumors, sex-cord-stromal tumors, uterine sarcomas and carcinosarcomas, gestational trophoblastic neoplasia, vulvar carcinoma and melanoma of the female genital tract, are defined as rare with an annual incidence of <6 per 100,000 women. Rare gynecological cancers (RGCs) are associated with poor prognosis, and given the low incidence of each entity, there is the risk of delayed diagnosis due to clinical inexperience and limited therapeutic options. There has been a growing interest in the field of microRNAs (miRNAs), a class of small non-coding RNAs of ∼22 nucleotides in length, because of their potential to regulate diverse biological processes. miRNAs usually induce mRNA degradation and translational repression by interacting with the 3' untranslated region (3'-UTR) of target mRNAs, as well as other regions and gene promoters, as well as activating translation or regulating transcription under certain conditions. Recent research has revealed the enormous promise of miRNAs for improving the diagnosis, therapy and prognosis of all major gynecological cancers. However, to date, only a few studies have been performed on RGCs. In this review, we summarize the data currently available regarding RGCs.

Molecular Characterization of Ovarian Yolk Sac Tumor (OYST)

Simple Summary

Ovarian yolk sac tumors (OYSTs) are rare and specific therapeutic strategies are needed after the failure of platinum-based first-line and salvage regimens. This retrospective study included ten patients with OYST, including patients with relapsed disease and disease-free patients. Three patients (33.3%) harbored oncogenic mutations in KRAS, KIT and ARID1A, which may be used as a target. Our series shows that relapsed patients with molecular analysis had clinically relevant molecular alterations. Future research with dedicated trials and multicenter international collaborations are needed to demonstrate the efficacy of specific therapeutic strategies after failure of platinum-based first-line and salvage regimens.

Abstract

Most patients with malignant ovarian germ cell tumors (MOGTCs) have a very good prognosis and chemotherapy provides curative treatment; however, patients with yolk sac tumors (OYSTs) have a significantly worse prognosis. OYSTs are rare tumors and promising results are expected with the use of specific therapeutic strategies after the failure of platinum-based first-line and salvage regimens. We initiated a project in collaboration with EORTC SPECTA, to explore the molecular characteristics of OYSTs. The pilot project used retrospective samples from ten OYST relapsed and disease-free patients. Each patient had a molecular analysis performed with FoundationOne CDx describing the following variables according to the Foundation Medicine Incorporation (FMI): alteration type (SNV, deletion), actionable gene alteration, therapies approved in EU (for patient’s tumor type and other tumor types), tumor mutational burden (TMB), and microsatellite instability (MSI) status. A total of 10 patients with OYST diagnosed between 2007 and 2017 had a molecular analysis. A molecular alteration was identified in four patients (40%). A subset of three patients (33.3% of all patients) harbored targetable oncogenic mutations in KRAS, KIT, ARID1A. Two patients at relapse harbored a targetable mutation. This retrospective study identifies clinically relevant molecular alterations for all relapsed patients with molecular analysis. Dedicated studies are needed to demonstrate the efficacy of specific therapeutic strategies after the failure of platinum-based first-line and salvage regimens and to explore the potential relationship of a molecular alteration and patient outcome.

The Latest Findings of PD-1/PD-L1 Inhibitor Application in Gynecologic Cancers

Gynecologic cancers account for approximately 11% of the newly diagnosed cancers in women in the United States and for 18% globally. The presence of tumor-infiltrating lymphocytes (TILs) influences the clinical outcome of cancer patients and immune checkpoint inhibitors (ICIs), including anti programmed cell death protein-1 (anti-PD-1), anti-programmed death-ligand 1 (anti-PD-L1), and anticytotoxic T-lymphocyte antigen 4 (anti-CTLA-4), which have been approved for treating different types of malignancies. Antibodies targeting the PD-1/PD-L1 checkpoint have shown dynamic and durable tumor regressions, suggesting a rebalancing of the host-tumor interaction. There are several the US food and drug administration (FDA)-approved ICIs targeting PD-1, including pembrolizumab and nivolumab, as well as those targeting PD-L1, including avelumab, atezolizumab, and durvalumab for melanoma, renal cell cancer, colorectal cancer, head and neck cancer, cervix cancer, urothelial cancer, and lung cancer. Current pre-clinical and clinical studies assessing PD-1/PD-L1 inhibitors in several gynecologic cancers have reported significant antitumor activity. In this review, we investigate pre-clinical and clinical studies that describe the safety and efficacy of anti-PD-1/PD-L1 antibodies, with a particular focus on ongoing clinical trials, analyzing the oncological outcome and adverse effects of ICIs in gynecologic cancers.

Molecular Pathways and Targeted Therapies for Malignant Ovarian Germ Cell Tumors and Sex Cord-Stromal Tumors: A Contemporary Review

Non-epithelial ovarian tumors are heterogeneous and account for approximately 10% of ovarian malignancies. The most common subtypes of non-epithelial ovarian tumors arise from germ cells or sex cord and stromal cells of the gonads. These tumors are usually detected at an early stage, and management includes surgical staging and debulking. When indicated for advanced disease, most respond to chemotherapy; however, options for patients with refractory disease are limited, and regimens can be associated with significant toxicities, including permanent organ dysfunction, secondary malignancies, and death. Targeted therapies that potentially decrease chemotherapy-related adverse effects and improve outcomes for patients with chemotherapy-refractory disease are needed. Here, we review the molecular landscape of non-epithelial ovarian tumors for the purpose of informing rational clinical trial design. Recent genomic discoveries have uncovered recurring somatic alterations and germline mutations in subtypes of non-epithelial ovarian tumors. Though there is a paucity of efficacy data on targeted therapies, such as kinase inhibitors, antibody–drug conjugates, immunotherapy, and hormonal therapy, exceptional responses to some compounds have been reported. The rarity and complexity of non-epithelial ovarian tumors warrant collaboration and efficient clinical trial design, including high-quality molecular characterization, to guide future efforts.

Targeting high transcriptional control activity of long mononucleotide A-T repeats in cancer by Argonaute 1

Epigenetic regulatory changes alter the gene regulation function of DNA repeat elements in cancer and consequently promote malignant phenotypes. Some short tandem repeat sequences, distributed throughout the human genome, can play a role as cis-regulatory elements of the genes. Distributions of tandem long (≥10) and short (<10) A-T repeats in the genome are different depending on gene functions. Long repeats are more commonly found in housekeeping genes and may regulate genes in harmonious fashion. Mononucleotide A-repeats around transcription start sites interact with Argonaute proteins (AGOs) to regulate gene expression. miRNA-bound AGO alterations in cancer have been reported; consequently, these changes would affect genes containing mononucleotide A- and T-repeats. Here, we showed an unprecedented hallmark of gene regulation in cancer. We evaluated the gene expression profiles reported in the Gene Expression Omnibus and found a high density of 13-27 A-T repeats in the up-regulated genes in malignancies derived from the bladder, cervix, head and neck, ovary, vulva, breast, colon, liver, lung, prostate, kidney, thyroid, adrenal gland, bone, blood cells, muscle and brain. Transfection of cell-penetrating protein tag AGO1 containing poly uracils (CPP-AGO1-polyUs) to the lung cancer cell lines altered gene regulation depending on the presence of long A-T repeats. CPP-AGO1-polyUs limited cell proliferation and the ability of a cancer cell to grow into a colony in lung cancer cell lines. In conclusion, long A-T repeats up-regulated many genes in cancer that can be targeted by AGO1 to change the expression of many genes and limited cancer growth.

PI3K inhibitor enhances the cytotoxic response to etoposide and cisplatin in a newly established neuroendocrine cervical carcinoma cell line

BACKGROUND

Neuroendocrine cervical carcinoma (NECC) is a rare and aggressive subtype of cervical cancer. To date, no NECC cell-based model is available, which hinders the development of new therapeutic strategies for NECC. In this study, we derived a new NECC cell line from an ex vivo biopsy and used it to explore novel drug combination approach for NECC.

RESULTS

The stable HM-1 cell line displayed high expression levels of the neuroendocrine marker, synaptophysin. HM-1 cell transplantation could induce tumor growth in nude mice. As expected, the combination of etoposide and cisplatin synergistically inhibited HM-1 cell proliferation. Strikingly, when etoposide and cisplatin were combined with PI3K inhibitor BEZ235, the growth of HM-1 cells was significantly reduced. Taken together, the data implied the combination of etoposide and cisplatin with BEZ235 not only inhibited HM-1 cell proliferation but also increased cell apoptosis.

MATERIALS AND METHODS

A NECC tissue sample from a 75-year-old female patient was processed to derive a primary cell line annotated as HM-1. The features of HM-1 were analyzed to establish its characteristic profile. Next, HM-1 was treated with PI3K inhibitors, BKM120 and/or BEZ235, in combination with two well-known genotoxic drugs, etoposide and/or cisplatin, to evaluate which combination could serve as a more effective treatment approach. Their inhibiting effects on HM-1 were evaluated by cell viability, apoptosis, and target kinase expression.

CONCLUSIONS

The newly established NECC cell line HM-1 could serve as a cell-based model for NECC research. The synergistic drug combination of PI3K inhibitor with genotoxic drugs might become a potential new treatment strategy against NECC.

The management of small-cell carcinomas of the gynecologic tract

PURPOSE OF REVIEW

Small-cell carcinomas of the gynecologic tract are aggressive malignancies that can be misdiagnosed or inappropriately managed. This review provides a summary of current literature that will help the clinician to correctly diagnose and treat patients with small-cell carcinomas of the cervix, ovary, uterus, vagina, and vulva.

RECENT FINDINGS

Small-cell carcinomas of gynecologic sites are rare and carry a poor prognosis. Stage is an important prognostic factor in small-cell carcinoma of the cervix, uterus, and ovary. Early stage disease has varied treatment approaches based on the site of malignancy, but systemic chemotherapy with or without radiation plays a role in the adjuvant setting to mitigate the risk of recurrence. Advanced stage patients require treatment with chemotherapy and possibly radiation, usually in a manner analogous to small-cell lung cancer. The preferred chemotherapy regimen contains a platinum agent and etoposide. For small-cell ovarian carcinomas, it is important to differentiate those of the hypercalcemic type from those of the pulmonary type. The small-cell carcinomas of the vagina and vulva need to be distinguished from Merkel cell cancers.

SUMMARY

The majority of small-cell tumors of the gynecologic tract will require systemic chemotherapy with a platinum agent and etoposide, both in the setting of early and advanced stage disease. Prospective trials with new chemotherapy or targeted agents are needed to improve the treatment of this aggressive cancer.

Expression pattern of class I histone deacetylases in vulvar intraepithelial neoplasia and vulvar cancer: a tissue microarray study

BACKGROUND

Epigenetic regulation is an important mechanism leading to cancer initiation and promotion. Histone acetylation by histone deacetylases (HDACs) represents an important part of it. The development of HDAC inhibitors has identified the utility of HDACs as a therapeutic target. Little is known about the epigenetic regulation of vulvar intraepithelial neoplasia (VIN) and vulvar squamous cell cancer (VSCC). In this study, the expression of class I HDACs (HDAC 1, 2 and 3) was compared in a series of VIN and VSCC tissues.

METHODS

A tissue micro array (TMA) with specimens from 106 patients with high-grade VIN and 59 patients with vulvar cancer was constructed. The expression of HDACs 1, 2 and 3 were analyzed with immunohistochemistry (IHC). The nuclear expression pattern was evaluated in terms of intensity and percentage of stained nuclei and was compared between vulvar preinvasive lesions and vulvar cancer.

RESULTS

HDAC 2 expression was significantly higher in VIN than in VSCC (p < 0.001, Fisher's test). Also, 88.7% (n = 94/106) of VIN samples and only 54.5% (n = 31/57) of VSCC samples were scored at the maximum level. Conversely, HDAC 3 expression was significantly higher in VSCC (93%, 53/57) compared to VIN (73.6%, 78/106, p = 0.003), whereas only a small difference in the expression of HDAC 1 was found between these two entities of vulvar neoplasia.

CONCLUSIONS

These results suggest that epigenetic regulation plays a considerable role in the transformation of VIN to invasive vulvar neoplasia.

Expression of survivin, CD117, and C-erbB-2 in neuroendocrine carcinoma of the uterine cervix

OBJECTIVE

To evaluate the expression and prognostic significance of survivin, CD117, and C-erbB-2 in neuroendocrine carcinoma of the uterine cervix.

MATERIALS AND METHODS

Immunohistochemical stains of survivin, CD117, and C-erbB-2 were evaluated in 100 cases of cervical neuroendocrine carcinoma. The findings were correlated with clinicopathologic variables and disease-free survival.

RESULTS

Expressions of survivin, CD117, and C-erbB-2 were detected in 27.0%, 12.0%, and 2.0% of the cases, respectively. Survivin-positive patients had a significantly younger mean age than the survivin-negative group (P=0.033). In early-stage cases, tumor recurrence was significantly associated with lymph node metastasis (P=0.005), depth of invasion (P=0.028), and the presence of lymphovascular space invasion (P=0.031) but not with the expression of survivin or CD117. Subgroup analysis in early-stage cases without lymph node metastasis (n=32) showed that only survivin expression had a significant association with decreased disease-free survival (P=0.041).

CONCLUSIONS

Survivin expression may be a prognostic indicator for survival in early-stage neuroendocrine carcinoma of the uterine cervix without lymph node metastasis. Adjuvant survivin-targeted therapy may have potential benefit in patients with this tumor.

Multidisciplinary management of malignant ovarian germ cell tumours

OBJECTIVES

Malignant ovarian germ cell tumours (MOGCT) are rare cancers of young women. Limited prospective trials exist from which evidence-based management can be developed. This review summarizes the available literature concerning MOGT in order to provide the clinician with information relevant to their multidisciplinary management.

METHODS

MEDLINE was searched between 1966 and 2010 for all publications in English where the studied population included women diagnosed with malignant ovarian germ cell tumours.

RESULTS

The majority of patients can be cured with fertility-preserving surgery with or without combination chemotherapy. Long term survival approaches 100% in early stage disease and is approximately 75% in advanced stage disease. Most studies suggest that the treatment has little, if any, effect on future fertility and limited data suggest that there is no adverse effect on the future quality of life.

CONCLUSION

MOGCTs are rare tumours of young women the majority of which can be successfully treated with fertility-preserving surgery with or without chemotherapy with preservation of reproductive function. Minimisation of chemotherapy in good prognostic groups and improved treatment in resistant and relapsed MOGCT are important goals for the future. Further studies are needed to quantify the late adverse effects of treatment in long term survivors.

HERV-K hypomethylation in ovarian clear cell carcinoma is associated with a poor prognosis and platinum resistance

INTRODUCTION

In general, ovarian clear cell carcinoma (OCCC) has a history of poor response to standard platinum-based chemotherapy regimens, and advanced cases have short survival periods. Therefore, the discovery of a biomarker for the pretreatment prediction of OCCC is crucial. Loss of methylation of a retrotransposable sequence, such as long interspersed repetitive sequence 1 (LINE-1), frequently occurs in cancers, including ovarian cancer, and it has been proven to be associated with poor survival. The expressions of human endogenous retrovirus (HERV) K and E were found to be increased in tissues from patients with OCCC. Here, we propose that methylation levels of HERV are associated with treatment response and prognosis of OCCC.

METHODS

Twenty-nine patients with OCCC were enrolled. Methylation levels of HERV-K, HERV-E, and LINE-1 were measured from microdissected cancer and normal ovarian tissues. The methylation levels were correlated with stage, treatment response, and prognosis.

RESULTS

Methylation levels of HERV-K, HERV-E, and LINE-1 were decreased in tissues from patients with advanced stage cancer (P = 0.0179, P = 0.0021, and P = 0.0307, respectively). Human endogenous retrovirus K demonstrated significantly lower methylation levels in the platinum-resistant group (P = 0.0004). Patients with lower levels of methylated (hypomethylated) HERV-K had a shorter mean overall survival (P = 0.006). In advanced OCCC cases, patients with hypomethylated HERV-K had shorter mean progression-free survival (P = 0.018) and mean overall survival (P = 0.018) than did patients with higher methylation levels of HERV-K.

CONCLUSIONS

Methylation levels of HERV-K, HERV-E, and LINE-1 are decreased during OCCC multistep carcinogenesis. Moreover, HERV-K hypomethylation is a promising biomarker for predicting OCCC treatment response and prognosis.