Aneuploidy related transcriptional changes in endometrial cancer link low expression of chromosome 15q genes to poor survival

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.

The emerging links between chromosomal instability (CIN), metastasis, inflammation and tumour immunity

Many cancers possess an incorrect number of chromosomes, a state described as aneuploidy. Aneuploidy is often caused by Chromosomal Instability (CIN), a process of continuous chromosome mis-segregation. CIN is believed to endow tumours with enhanced evolutionary capabilities due to increased intratumour heterogeneity, and facilitating adaptive resistance to therapies. Recently, however, additional consequences and associations with CIN have been revealed, prompting the need to understand this universal hallmark of cancer in a multifaceted context. This review is focused on the investigation of possible links between CIN, metastasis and the host immune system in cancer development and treatment. We specifically focus on these links since most cancer deaths are due to the consequences of metastasis, and immunotherapy is a rapidly expanding novel avenue of cancer therapy.

PIK3CA Amplification Associates with Aggressive Phenotype but Not Markers of AKT-MTOR Signaling in Endometrial Carcinoma

PURPOSE

Amplification of PIK3CA, encoding the PI3K catalytic subunit alpha, is common in uterine corpus endometrial carcinoma (UCEC) and linked to an aggressive phenotype. However, it is unclear whether PIK3CA amplification acts via PI3K activation. We investigated the association between PIK3CA amplification, markers of PI3K activity, and prognosis in a large cohort of UCEC specimens.

EXPERIMENTAL DESIGN

UCECs from 591 clinically annotated patients including 83 tumors with matching metastasis (n = 188) were analyzed by FISH to determine PIK3CA copy-number status. These data were integrated with mRNA and protein expression and clinicopathologic data. Results were verified in The Cancer Genome Atlas dataset.

RESULTS

PIK3CA amplifications were associated with disease-specific mortality and with other markers of aggressive disease. PIK3CA amplifications were also associated with other amplifications characteristic of the serous-like somatic copy-number alteration (SCNA)-high subgroup of UCEC. Tumors with PIK3CA amplification also demonstrated an increase in phospho-p70S6K but had decreased levels of activated phospho-AKT1-3 as assessed by Reverse Phase Protein Arrays and an mRNA signature of MTOR inhibition.

CONCLUSIONS

PIK3CA amplification is a strong prognostic marker and a potential marker for the aggressive SCNA-high subgroup of UCEC. Although PIK3CA amplification associates with some surrogate measures of increased PI3K activity, markers for AKT1-3 and MTOR signaling are decreased, suggesting that this signaling is not a predominant pathway to promote cancer growth of aggressive serous-like UCEC. Moreover, these associations may reflect features of the SCNA-high subgroup of UCEC rather than effects of PIK3CA amplification itself.