Malignant tumors of the uterine corpus: molecular background of their origin

Epigenetic Features in Uterine Leiomyosarcoma and Endometrial Stromal Sarcomas: An Overview of the Literature

There is a consensus that epigenetic alterations play a key role in cancer initiation and its biology. Studies evaluating the modification in the DNA methylation and chromatin remodeling patterns, as well as gene regulation profile by non-coding RNAs (ncRNAs) have led to the development of novel therapeutic approaches to treat several tumor types. Indeed, despite clinical and translational challenges, combinatorial therapies employing agents targeting epigenetic modifications with conventional approaches have shown encouraging results. However, for rare neoplasia such as uterine leiomyosarcomas (LMS) and endometrial stromal sarcomas (ESS), treatment options are still limited. LMS has high chromosomal instability and molecular derangements, while ESS can present a specific gene fusion signature. Although they are the most frequent types of "pure" uterine sarcomas, these tumors are difficult to diagnose, have high rates of recurrence, and frequently develop resistance to current treatment options. The challenges involving the management of these tumors arise from the fact that the molecular mechanisms governing their progression have not been entirely elucidated. Hence, to fill this gap and highlight the importance of ongoing and future studies, we have cross-referenced the literature on uterine LMS and ESS and compiled the most relevant epigenetic studies, published between 2009 and 2022.

The risk of distant metastases in patients with gynecologic cancers after surgery: a population-based study

The aim of the study was to determine the risk of distant metastases in patients with gynecologic cancers after surgery, including cervical, uterine and ovarian cancers. This is a retrospective study evaluating gynecologic cancer from 2009 to 2014 using population-based administrative datasets from the Health and Welfare Data Science Center (HWDC) and from The National Health Informatics Project (NHIP). A total of 1,464 gynecologic cancer patients, including 321 cervical cancer patients, 724 uterine cancer patients and 419 ovarian cancer patients, were analyzed retrospectively from 2009 to 2014. Among the cervical cancer patients, 173 (53.89%) received surgery only and 148 (46.11%) received surgery with radiotherapy /chemotherapy. Among the uterus cancer patients, 425(58.70%) received surgery only and 299 (41.3%) received surgery with radiotherapy /chemotherapy. Among the ovarian cancer patients, 81 (19.33%) received surgery only and 338 (80.67%) received surgery with radiotherapy/chemotherapy. Among patients with brain, liver or lung metastasis, cervical cancer patients have more cumulative metastasis-free survival than those ovarian cancer (p=0.0041). In analyzing liver metastasis based on primary cancer sites, cervical cancer patients and uterine cancer cases have more cumulative metastasis- free survival than those ovarian cancer (p<0.0001). In conclusion, ovarian cancer patients have higher risk of liver metastasis than cervical or uterine cancer. There were significantly different of pathological stage for cumulative metastasis-free survival among gynecologic cancer patients with brain or liver or lung metastasis. Pathological T stage remains the main predictive for distant metastasis of gynecologic cancer.

A Danish nationwide study of risk factors associated with Type I and Type II endometrial cancer

OBJECTIVE

To examine risk factors for Type I and Type II endometrial cancer (EC) and to directly compare the influence of risk factors for Type II with Type I tumors. Furthermore, to examine whether risk factors for high-grade Type I and Type II tumors differed from low-grade Type I tumors.

METHODS

Women with EC diagnosed during 2000-2016 were identified in the Danish Cancer Registry. A case-control analysis was conducted with 1:15 random population controls matched on age and gender. Using conditional logistic regression, odds ratios and 95% confidence intervals on risk factors for Type I and II tumors were estimated. In case-case analyses, risk factors were evaluated in a direct comparison of cases grouped by tumor type and grade.

RESULTS

We identified 6958 women with Type I EC and 1206 women with Type II EC. In the case-control analysis, nulliparity and diabetes were associated with increased risk of both tumor types, whereas hormone replacement therapy only increased the risk of Type I EC. When directly comparing Type I and II tumors, the influence of BMI ≥ 30, current smoking, and parity ≥ 3 was strongest for Type I EC. The associations for the majority of risk factors were similar for Type II and high-grade Type I tumors compared with low-grade Type II tumors.

CONCLUSIONS

Risk factors for Type I and II tumors were overlapping suggesting that Type II tumors may be less estrogen-independent than previously anticipated. High-grade Type I tumors seemed to resemble Type II tumors more than low-grade Type I tumors.

miRNAs 144-3p, 34a-5p, and 206 are a useful signature for distinguishing uterine leiomyosarcoma from other smooth muscle tumors

Background

Leiomyosarcoma (LMS) is a rare uterine neoplasm that has a high mortality rate and no specific treatment. The origin of LMS remains unknown; although, it is hypothesized that LMS arises from the malignant transformation of a degenerated uterine leiomyoma (LM). LMs are the most common benign tumors diagnosed and rare variants of LM (unconventional LM) morphologically resemble LMS, thereby making an early and precise diagnosis of LMS difficult. Various molecular features may influence the malignancy risk of LMS tumors, including microRNAs (miRNAs). However, the role of miRNAs in uterine mesenchymal tumors remains poorly understood. Here, our aim was to assess the miRNA expression profiles of LMS, LM, and LM variants (ULM) to identify a specific signature that may facilitate differentiation among these tumor types. Possible associations between these profiles and patients’ clinical and pathological features were also analyzed.

Methods

Total RNA was extracted from formalin-fixed paraffin-embedded tissue samples of uterine LMS (n = 37), LM (n = 3), ULM (n = 8), and myometrium (MM) (n = 2) to perform real-time PCR analyses and detect expression levels of a panel of 84 miRNA sequences related to cancer.

Results

Between the LMS and LM samples, 16 miRNAs were found to be differentially expressed, with miR-372 and miR-34a-5p exhibiting the highest and lowest levels of expression, respectively. When LMS and ULM were compared, 5 differentially expressed miRNAs were identified, with miR-34a-5p downregulated and miR-144-3p upregulated. Between ULM and LM, all of the differentially expressed miRNAs were upregulated, and miR122-5p exhibited 10-fold higher expression. In addition, significant correlations were found between various miRNAs and tumor relapse (miR-148a-3p), metastasis (miR-27b-3p), and patient death (miR-124-3p and miR-183-5p). Downregulation of miR135b-5p was associated with disease-free survival.

Conclusion

Expression profiling of miRNAs 144-3p, 34a-5p, and 206 may be useful in characterizing uterine LMS and distinguishing it from benign tumors. Furthermore, deregulation of miRNAs 148a-3p, 27b-3p, 124-3p, 183-5p, and 135b-5p appear to indicate a poor prognosis for LMS patients.