Microsatellite instability and ploidy status define three categories with distinctive prognostic impact in endometrioid endometrial cancer

Microsatellite instability as a marker of prognosis: a systematic review and meta-analysis of endometrioid endometrial cancer survival data

INTRODUCTION

To investigate whether microsatellite instability (MSI) is an important prognostic biomarker for endometrioid endometrial cancer (EEC).

METHODS

The PubMed, EMBASE, and the Cochrane Cooperative Library databases were searched from inception to July 2021. Overall survival, disease-free survival, progression-free survival, EEC-specific survival, recurrence-free survival, and the recurrence rate were pooled to analyze the correlation between MSI and EEC. In addition, Egger's regression analysis and Begg's test were used to detect publication bias.

RESULTS

17 studies met the inclusion criteria and were included in our meta-analysis with a sample size of 4723, and the included patients with endometrioid cancer (EC) all were EEC. The pooled hazard ratios (HR) in patients with EEC showed that MSI was significantly associated with shorter overall survival [HR = 1.37, 95% confidence interval (CI) (1.00-1.86), p = 0.048, I2 = 60.6%], shorter disease-free survival [HR = 1.99, 95% CI (1.31-3.01), p = 0.000, I2 = 67.2%], shorter EEC-specific survival [HR = 2.07, 95% CI (1.35-3.18), p = 0.001, I2 = 31.6%] and a higher recurrence rate [Odds ratios (OR) = 2.72, 95% CI (1.56-4.76), p = 0.000, I2 = 0.0%]. In the early-stage EEC subgroup, MSI was significantly associated with shorter overall survival [HR = 1.47, 95% CI (1.11-1.95), p = 0.07], shorter disease-free survival [HR = 4.17, 95% CI (2.37-7.41), p = 0.000], and shorter progression-free survival [HR = 2.41, 95% CI (1.05-5.54), p = 0.039]. No significant heterogeneity was observed in overall survival (I2 = 20.9%), disease-free survival (I2 = 0.0%), or progression-free survival (I2 = 0.0%) in patients with early-stage EEC. Meanwhile, publication bias was not observed, and the p-value for Egger's test of overall survival, disease-free survival, and EEC-specific survival were p = 0.131, p = 0.068, and p = 0.987, respectively.

CONCLUSION

MSI is likely an important biomarker for poor prognosis in patients with EEC, and this correlation is even more certain in patients with early-stage EEC.

Combination of aneuploidy and high S-phase fraction indicates increased risk of relapse in stage I endometrioid endometrial carcinoma

INTRODUCTION

Endometrioid endometrial carcinoma is a cancer type with generally excellent prognosis when diagnosed at an early stage, but there is a subset of patients with relapsing disease in spite of early diagnosis and surgical treatment. There is a need to find prognostic markers to identify these patients with increased risk of relapse. Depth of myometrial invasion, histological grade, and presence of lymphovascular invasion are known risk factors. DNA content (ploidy) and proliferation measured as S-phase fraction (SPF) have been discussed as prognostic markers but need additional evaluation.

MATERIAL AND METHODS

We evaluated relapse-free survival (RFS) with respect to ploidy and SPF, which was analyzed by flow cytometry on fresh tumor tissue, in a cohort of 1001 women treated for stage I endometrioid endometrial carcinoma in northern Sweden during the period of 1993-2010, with a median follow up time of 12.0 years. Data were obtained from historical records.

RESULTS

In simple analysis, both aneuploidy and high SPF were associated to increased risk of relapse with hazard ratios (HR) 2.37 (95% CI 1.52-3.70) and 1.94 (95% CI 1.24-3.02), respectively. Our data also confirmed stage, tumor grade, and ploidy as independent prognostic markers in an age adjusted cox regression multivariable analysis but we did not find SPF to contribute to prognosis. However, the combination of aneuploidy and high SPF identified a group of patients with increased risk of relapse, HR 2.02 (95% CI 1.19-3.44).

CONCLUSION

In this study, which is the largest study of ploidy and SPF in stage I endometrioid endometrial carcinoma using fresh frozen tissue, aneuploidy was shown to be an independent prognostic marker. Furthermore, the combination of aneuploidy and high SPF could be used to identify patients with increased risk of relapse.

An immune competent orthotopic model of endometrial cancer with metastasis

Endometrial cancer is the most common gynecologic malignancy in the U.S. with metastatic disease remaining the major cause of patient death. Therapeutic strategies have remained essentially unchanged for decades. A significant barrier to progression in treatment modalities stems from a lack of clinically applicable in vivo models to accurately mimic endometrial cancer; specifically, ones that form distant metastases and maintain an intact immune system. To address this problem, we have established the first immune competent murine orthotopic tumor model for metastatic endometrial cancer by creating a green fluorescent protein labeled cell line from an endometrial cancer that developed in a Pgr ^cre/+ Pten ^f/f Kras ^G12D genetically engineered mouse. These cancer cells were grafted into the abraded uterine lumen of ovariectomized recipient mice treated with estrogen and subsequently developed local and metastatic endometrial tumors. We noted primary tumor formation in 59% mixed background and 86% of C57BL/6 animals at 4 weeks and distant lung metastases in 78% of mice after 2 months. This immunocompetent orthotopic tumor model closely resembles some human metastatic endometrial cancer, modeling both local metastasis and hematogenous spread to lung and has significant potential to advance the study of endometrial cancer and its metastasis.

Mismatch repair deficiency and aberrations in the Notch and Hedgehog pathways are of prognostic value in patients with endometrial cancer

The aim of this study was to investigate the prognostic value of the Hedgehog (Gli, Patched-1, Shh, Smo) and Notch (Jag1, Notch2, Notch3) pathway members, in comparison to a panel of proteins (ER, PgR, HER2/neu, Ki67, p53, p16, PTEN and MMR) previously suggested to be involved in the pathogenesis of endometrial cancer, in association with clinical outcome and standard clinicopathological characteristics. A total of 204 patients with histological diagnosis of endometrial cancer treated from 2004 to 2013 were included. The evaluation of protein expression was assessed by immunohistochemistry. Univariate analysis showed that higher Ki67 labeling, expression of PTEN, p16, Notch2 and Notch3 proteins, as well as MMR proficiency were associated with increased relapse and mortality rate. Additionally, Patched-1 protein expression was associated with worse DFS, while p53 overexpression was associated with worse OS. In multivariate analyses, patients with MMR proficient tumors had more than double risk for death than patients with MMR deficient (MMRd) tumors (adjusted HR = 2.19, 95% CI 1.05–4.58, p = 0.036). Jag1 positivity conferred reduced mortality risk (HR = 0.48, 95% CI 0.23–0.97, p = 0.042). However, as shown by hierarchical clustering, patients fared better when their tumors expressed high Jag1 protein in the absence of Notch2 and Notch3, while they fared worse when all three proteins were highly expressed. Patched-1 positivity conferred higher risk for relapse (HR = 2.04, 95% CI 1.05–3.96, p = 0.036).

Aberrant expression of key components of the Notch and Hedgehog signaling pathways, as well as MMRd may serve as independent prognostic factors for recurrence and survival in patients with endometrial cancer.

Assessment of DNA Ploidy in the ProMisE molecular subgroups of endometrial cancer

OBJECTIVE

We sought to determine whether DNA ploidy correlates with the four molecular subgroups of endometrial carcinoma (EC) as determined using ProMisE (Proactive Molecular Risk Classifier for Endometrial Cancer).

METHODS

90 cases of EC previously characterized by clinicopathological parameters, outcomes, and ProMisE molecular subgroup (POLE EDM, MMR-D, p53 wt or p53 abn) were assessed for DNA ploidy using image cytometry. Associations of ploidy with traditional clinicopathological parameters were also tested.

RESULTS

Abnormal DNA ploidy status differed amongst the ProMisE groups (p<0.001) and was found in 80.9% (17/21) of p53 abn, 37.0% (10/27) of p53 wt, 28.6% (4/14) of POLE EDM and 14.3% (4/28) of MMR-D. Abnormal DNA content was significantly associated with lower BMI (p=0.034) and grade 3 tumors (p=0.001). In the entire cohort, abnormal DNA content was significantly associated with worse progression free survival (p=0.0094) but not disease specific survival (p=0.249) or overall survival (p=0.187). When examining ploidy within each of the ProMisE groups, abnormal DNA content correlated with worse overall survival (p=0.041) and progression free survival (p=0.011) in the MMR-D group. No statistically significant relationship was seen in the remaining 3 groups.

CONCLUSION

Abnormal DNA ploidy status did correlate with the molecular subgroups of EC; abnormal DNA content was seen in the large majority of p53 abn cases. Abnormal ploidy however was also seen in smaller numbers in the p53 wt, POLE EDM and MMR-D groups; therefore abnormal DNA content was not a specific marker for any one molecular group. The addition of ploidy to the ProMisE molecular categories conferred additional prognostic value within the MMR-D group, which merits further study.

LncRNA HOTAIR promotes human liver cancer stem cell malignant growth through downregulation of SETD2

Long non-coding RNA HOTAIR predicts negative tumor prognosis and exhibits oncogenic activity. Herein, we demonstrate HOTAIR promotes human liver cancer stem cell malignant growth through downregulation of SETD2. Mechanistically, HOTAIR reduces the recuritment of the CREB, P300, RNA polII onto the SETD2 promoter region that inhibits SETD2 expression and its phosphorylation. Thereby, the SETD2 binding capacity to substrate histone H3 is weakened, triggering a reduction of trimethylation on histone H3 thirty-sixth lysine, and thereby the H3K36me3–hMSH2-hMSH6-SKP2 complex is also decreased. Strikingly, the complex occupancy on chromosome is depressed, preventing from mismatch DNA repair. While reducing the degradation capacity of Skp₂ for aging histone H3 bound to damaged DNA, the aging histone repair is impaired. Furthermore, that the damaged DNA escaped to repair can causes microsatellite instability(MSI) and abnormal expression of cell cycle related genes that may trigger the hepatocarcinogenesis. This study provides evidence for HOTAIR to promote tumorigenesis via downregulating SETD2 in liver cancer stem cells.

Clinicopathologic Significance of Mismatch Repair Defects in Endometrial Cancer: An NRG Oncology/Gynecologic Oncology Group Study

PURPOSE

The clinicopathologic significance of mismatch repair (MMR) defects in endometrioid endometrial cancer (EEC) has not been definitively established. We undertook tumor typing to classify MMR defects to determine if MMR status is prognostic or predictive.

METHODS

Primary EECs from NRG/GOG0210 patients were assessed for microsatellite instability (MSI), MLH1 methylation, and MMR protein expression. Each tumor was assigned to one of four MMR classes: normal, epigenetic defect, probable mutation (MMR defect not attributable to MLH1 methylation), or MSI-low. The relationships between MMR classes and clinicopathologic variables were assessed using contingency table tests and Cox proportional hazard models.

RESULTS

A total of 1,024 tumors were assigned to MMR classes. Epigenetic and probable mutations in MMR were significantly associated with higher grade and more frequent lymphovascular space invasion. Epigenetic defects were more common in patients with higher International Federation of Gynecology and Obstetrics stage. Overall, there were no differences in outcomes. Progression-free survival was, however, worse for women whose tumors had epigenetic MMR defects compared with the MMR normal group (hazard ratio, 1.37; P < .05; 95% CI, 1.00 to 1.86). An exploratory analysis of interaction between MMR status and adjuvant therapy showed a trend toward improved progression-free survival for probable MMR mutation cases.

CONCLUSION

MMR defects in EECs are associated with a number of well-established poor prognostic indicators. Women with tumors that had MMR defects were likely to have higher-grade cancers and more frequent lymphovascular space invasion. Surprisingly, outcomes in these patients were similar to patients with MMR normal tumors, suggesting that MMR defects may counteract the effects of negative prognostic factors. Altered immune surveillance of MMR-deficient tumors, and other host/tumor interactions, is likely to determine outcomes for patients with MMR-deficient tumors.

PIKing the type and pattern of PI3K pathway mutations in endometrioid endometrial carcinomas

OBJECTIVE

The vast majority of endometrioid endometrial carcinomas (EECs) harbor mutations in the PI3K pathway. Here we sought to determine whether the type and pattern of mutations targeting different components of the PI3K pathway are distinct between microsatellite stable (MSS) and high-level microsatellite instable (MSI-H) EECs.

METHODS

Whole exome massively parallel sequencing-based mutation data from EECs of The Cancer Genome Atlas (TCGA) were used to define the number, type and pattern of mutations affecting PI3K pathway-related genes, including AKT1, INPP4B, MTOR, PIK3CA, PIK3R1 and PTEN. EECs were classified as MSI-H (n=70) and MSS (n=109) based on seven MSI markers assessed by TCGA. Ultramutated cases were excluded.

RESULTS

Although the mutation rates and mutational signatures of MSS and MSI-H EECs were distinct, the prevalence of PI3K pathway mutations was similar between these two groups (all p>0.05), with the exception of PTEN mutations, which were more prevalent in MSI-H (61/70; 87%) than in MSS EECs (78/109; 72%; p=0.017). The PIK3CA hotspot mutations E542K, E545K, and H1047R were found to be significantly more prevalent in PIK3CA-mutant MSS (21/58, 36%) compared to PIK3CA-mutant MSI-H EECs (5/37, 13.5%; p=0.019).

CONCLUSION

Although the prevalence of mutations targeting PI3K pathway genes is similar between MSS and MSI-H EECs, PIK3CA hotspot mutations, which result in constitutive kinase activation, are significantly more prevalent in MSS than in MSI-H EECs. Our findings warrant further investigation of the role of different types of PIK3CA mutations and their predictive impact on distinct subtypes of EECs.