Tracking the origin of simultaneous endometrial and ovarian cancer by next-generation sequencing - a case report

Cancer and Autism: How PTEN Mutations Degrade Function at the Membrane and Isoform Expression in the Human Brain

Mutations causing loss of PTEN lipid phosphatase activity can promote cancer, benign tumors (PHTS), and neurodevelopmental disorders (NDDs). Exactly how they preferentially trigger distinct phenotypic outcomes has been puzzling. Here, we demonstrate that PTEN mutations differentially allosterically bias P loop dynamics and its connection to the catalytic site, affecting catalytic activity. NDD-related mutations are likely to sample conformations of the functional wild-type state, while sampled conformations for the strong, cancer-related driver mutation hotspots favor catalysis-primed conformations, suggesting that NDD mutations are likely to be weaker, and our large-scale simulations show why. Prenatal PTEN isoform expression data suggest exons 5 and 7, which harbor NDD mutations, as cancer-risk carriers. Since cancer requires more than a single mutation, our conformational and genomic analysis helps discover how same protein mutations can foster different clinical manifestations, articulates a role for co-occurring background latent driver mutations, and uncovers relationships of splicing isoform expression to life expectancy.

Synchronous endometrial and ovarian cancer: A case report

BACKGROUND

Synchronous endometrial and ovarian cancer (SEOC) is a rare genital tract tumor. Precise diagnosis is crucial for the disease management since prognosis and overall survival differ substantially between metastatic endometrial cancer (EC) or OC. In this review we present 2 cases of women who were diagnosed with SEOC, and discuss the clinical characteristic of SEOC, diagnostic and molecular profiling issues. Next generation sequencing of 10 gene panel was performed on cancerous tissue and uterine lavage samples.

CASE SUMMARY

In our report patients with SEOC had endometroid type histology with early stage and low-grade histology for both EC and OC. They underwent surgical treatment and staging. Next-generation sequencing of 10 gene-panel identified CTNNB1, PIK3CA, and PTEN gene mutations in ovarian tissue in one case, while none of these genes were mutated in other case. Literature review in support to our data suggest a good prognosis for SEOC diagnosed at early stage.

CONCLUSION

Accurate diagnosis of SEOC is essential for disease management and gene mutation analysis can be helpful as a complementary diagnostic and prognostic tool.

How PTEN mutations degrade function at the membrane and life expectancy of carriers of mutations in the human brain

PTEN dysfunction, caused by loss of lipid phosphatase activity or deletion, promotes pathologies, cancer, benign tumors, and neurodevelopmental disorders (NDDs). Despite efforts, exactly how the mutations trigger distinct phenotypic outcomes, cancer or NDD, has been puzzling. It has also been unclear how to distinguish between mutations harbored by isoforms, are they cancer or NDDs-related. Here we address both. We demonstrate that PTEN mutations differentially allosterically bias P-loop dynamics and its connection to the catalytic site, affecting catalytic activity. NDD-related mutations are likely to sample conformations present in the wild-type, while sampled conformations sheltering cancer-related hotspots favor catalysis-prone conformations, suggesting that NDD mutations are weaker. Analysis of isoform expression data indicates that if the transcript has NDD-related mutations, alone or in combination with cancer hotspots, there is high prenatal expression. If no mutations within the measured days, low expression levels. Cancer mutations promote stronger signaling and cell proliferation; NDDs' are weaker, influencing brain cell differentiation. Further, exon 5 is impacted by NDD or non-NDD mutations, while exon 7 is exclusively impacted by NDD mutations. Our comprehensive conformational and genomic analysis helps discover how same allele mutations can foster different clinical manifestations and uncovers correlations of splicing isoform expression to life expectancy.

High-Grade Serous Carcinoma Resulting From Rectal Endometriosis and Complicated With Ovarian Cancer

Endometriosis is one of the most common benign gynecological diseases. It shows similar attributes to those of some fatal tumors if it is becomes malignant. These attributes include invasion, implantation, and recurrence. Epidemiological, clinicopathological, molecular biological, and genetic evidence suggest that malignancy of endometriosis, referred to as endometriosis-associated malignancy (EAM), is histologically closely related to endometriosis. Atypical endometriosis, which usually causes EAM, is considered a transitional condition from benign endometriosis to cancer. Approximately 80% of EAMs occur in the ovary and are known as endometriosis-associated ovarian cancer (EAOC). However, extragonadal endometriosis is not common, and no earlier study reported an association between malignant transformation of rectal endometriosis and high-grade serous cancer. We report a rare case of high-grade serous carcinoma resulting from rectal endometriosis and complicated with ovarian cancer. A 63-year-old Chinese woman was admitted with a complaint of abdominal distension. We diagnosed the patient with ovarian carcinoma and decided on elective cytoreductive surgery as treatment for the patient. During the surgery, we found a solid mass of diameter 12 cm in the anterior rectal wall containing sticky brown fluid. Postoperative histopathological examination revealed high-grade serous carcinoma resulting from rectal endometriosis and complicated with ovarian cancer. The patient postoperatively received 6 cycles of chemotherapy consisting of carboplatin and paclitaxel and was followed up for 1 year with no recurrence of the condition.

Combination of Scoring Criteria and Whole Exome Sequencing Analysis of Synchronous Endometrial and Ovarian Carcinomas

OBJECTIVES

The purpose of this study was to distinguish synchronous primary endometrial and ovarian carcinomas from single primary tumor with metastasis by clinical pathologic criteria and whole exome sequencing (WES).

MATERIAL AND METHODS

Fifty-two patients with synchronous endometrial and ovarian carcinomas (SEOCs) between 2010 and 2017 were reviewed and subjected to WES.

RESULTS

On the basis of the Scully criteria, 11 cases were supposed as synchronous primary endometrial and ovarian carcinomas, 38 cases as single primary tumor with metastasis, and the remaining 3 cases (S50-S52) cannot be defined. Through a quantization scoring analysis, 9 cases that were scored 0-1 point were defined as synchronous primary endometrial and ovarian carcinomas, and 42 cases that were scored 3-8 points were defined as single primary tumor with metastasis. Two of the undefined cases were classified into metastatic disease, and another one that scored 2 points (S52) was subjected to WES. S52 was deemed synchronous primary endometrial and ovarian carcinomas, with few shared somatic mutations and overlapping copy number varieties. The finding of a serous component examined from the uterine endometrium samples further illustrated that the case was synchronous primary endometrial and ovarian carcinomas.

CONCLUSION

By scoring criterion, SEOCs were divided into 2 groups: synchronous primary endometrial and ovarian carcinoma group and single primary tumor with metastasis group. The analysis of clonality indicated that the case that scored 2 (S52) can be considered as synchronous primary endometrial and ovarian carcinomas. Scoring criteria of clinical pathology, along with the study of the WES, may further identify the classification of SEOCs.

Endometriosis-associated ovarian cancer: What have we learned so far?

Endometriosis is defined as the presence of ectopic endometrial tissue outside of the uterine cavity, most commonly in the ovaries and peritoneum. It is a complex disease that is influenced by multiple factors. It is also a common gynecological disorder and affects approximately 10-15% of all women of reproductive age. Recent molecular and pathological studies indicate that endometriosis may serve as a precursor of ovarian cancer (endometriosis-associated ovarian cancer, EAOC), particularly endometrioid and clear cell ovarian cancers. Although histological and epidemiological studies have demonstrated that endometriosis has a malignant potential, the molecular mechanism that underlies the malignant transformation of endometriosis is still controversial, and the precise mechanism of carcinogenesis must be fully elucidated. Currently, the development and improvement of a new sequencing technology, next-generation sequencing (NGS), has been increasingly relevant in cancer genomics research. Recently, NGS has also been utilized in clinical oncology to advance the personalized treatment of cancer. In addition, the sensitivity, speed, and cost make NGS a highly attractive platform compared to other sequencing modalities. For this reason, NGS may lead to the identification of driver mutations and underlying pathways associated with EAOC. Here, we present an overview of the molecular pathways that have led to the current opinions on the relationship between endometriosis and ovarian cancer.

Synchronous endometrioid endometrial and ovarian carcinomas are biologically related: A clinico-pathological and molecular (next generation sequencing) study of 22 cases

The criteria for distinction between independent primary tumors and metastasis from one site to the other in synchronous endometrioid endometrial and ovarian carcinoma (SEO) has been a matter of dispute for a long time. In our study we performed a comprehensive clinico-pathological and molecular analysis of 22 cases of SEO. Based on conventional clinico-pathological criteria the cases were classified as independent primary tumors (10 cases) and metastasis from one location to the other (12 cases). All tumors were analyzed by NGS with a panel of 73 genes (219 kbp). Clonal origin was confirmed in all cases by at least one shared mutation in PTEN, AKT1, PIK3CA, KRAS, TP53 and ARID1A. Two patients carried germline pathogenic mutation in cancer-predisposing genes BRCA1 or BARD1. Microsatellite instable phenotype was detected in 5/22 (22.7%) SEO, but in one case only in the endometrial tumor. In conclusion, our results showed that all 22 SEOs were clonally related, irrespectively of their clinico-pathological features. Even low grade and low stage tumors classified as independent primaries, according to the conventional morphological criteria, have a clonal origin. From the practical point of view, only the conventional morphological criteria should be used for the classification (staging) of these tumors. However, molecular profiling of these tumors may have prognostic and predictive meaning.

Tumor evolution and chemoresistance in ovarian cancer

Development of novel strategies to overcome chemoresistance is central goal in ovarian cancer research. Natural history of the cancer development and progression is being reconstructed by genomic datasets to understand the evolutionary pattern and direction. Recent studies suggest that intra-tumor heterogeneity (ITH) is the main cause of treatment failure by chemoresistance in many types of cancers including ovarian cancer. ITH increases the fitness of tumor to adapt to incompatible microenvironment. Understanding ITH in relation to the evolutionary pattern may result in the development of the innovative approach based on individual variability in the genetic, environment, and life style. Thus, we can reach the new big stage conquering the cancer. In this review, we will discuss the recent advances in understanding ovarian cancer biology through the use of next generation sequencing (NGS) and highlight areas of recent progress to improve precision medicine in ovarian cancer.

Potential for Mitochondrial DNA Sequencing in the Differential Diagnosis of Gynaecological Malignancies

In the event of multiple synchronous gynecological lesions, a fundamental piece of information to determine patient management, prognosis, and therapeutic regimen choice is whether the simultaneous malignancies arise independently or as a result of metastatic dissemination. An example of synchronous primary tumors of the female genital tract most frequently described are ovarian and endometrial cancers. Surgical findings and histopathological examination aimed at resolving this conundrum may be aided by molecular analyses, although they are too often inconclusive. High mitochondrial DNA (mtDNA) variability and its propensity to accumulate mutations has been proposed by our group as a tool to define clonality. We showed mtDNA sequencing to be informative in synchronous primary ovarian and endometrial cancer, detecting tumor-specific mutations in both lesions, ruling out independence of the two neoplasms, and indicating clonality. Furthermore, we tested this method in another frequent simultaneously detected gynecological lesion type, borderline ovarian cancer and their peritoneal implants, which may be monoclonal extra-ovarian metastases or polyclonal independent masses. The purpose of this review is to provide an update on the potential use of mtDNA sequencing in distinguishing independent and metastatic lesions in gynecological cancers, and to compare the efficiency of molecular analyses currently in use with this novel method.

Clonality, Heterogeneity, and Evolution of Synchronous Bilateral Ovarian Cancer

Synchronous bilateral ovarian cancer (SBOC) represents a relatively frequent occurrence and clinically relevant diagnostic dilemma. Delineation of its clonal architecture, genetic heterogeneity, and evolutionary trajectories may have important implications for prognosis and management of patients with SBOC. Here, we describe the results of next-generation whole-exome or whole-genome sequencing of specimens from 12 SBOC cases and report that bilateral tumors from each individual display a comparable number of genomic abnormalities and similar mutational signatures of single-nucleotide variations. Clonality indices based on tumor-specific alterations supported monoclonal origins of SBOC. Each of the ovarian lesions was nevertheless oligoclonal, with inferred metastatic tumors harboring more subclones than their primary counterparts. The phylogenetic structure of SBOC indicated that most cancer cell dissemination occurred early, when the primary carcinoma was still relatively small (<100 million cells). Accordingly, the mutation spectra and mutational signatures of somatic variants exhibited pronounced spatiotemporal differences in each patient. Overall, these findings suggest that SBOCs are clonally related and form through pelvic spread rather than independent multifocal oncogenesis. Metastatic dissemination is often an early event, with dynamic mutational processes leading to divergent evolution and intratumor and intertumor heterogeneity, ultimately contributing substantially to phenotypic plasticity and diverse clinical course in SBOC. Cancer Res; 77(23); 6551-61. ©2017 AACR.