Dusp6 immunohistochemistry is associated with the response of atypical endometrial hyperplasia and early endometrial cancer to conservative treatment.

OBJECTIVE: Dual-specificity phosphatase 6 (Dusp6) was proposed as a predictive marker of response of atypical endometrial hyperplasia (AEH) and early endometrial cancer (EEC) to conservative treatment. However, its predictive accuracy has never been calculated. We aimed to define it in conservatively treated AEH and EEC. METHODS: All patients <45 years with AEH or EEC and conservatively treated with hysteroscopic resection + LNG-IUD insertion from 2007 to 2018 were retrospectively assessed. Dusp6 immunohistochemical expression was assessed and dichotomized as "strong" vs "weak". Relative risk (RR) for "no regression" and "recurrence" or AEH/EEC was calculated. Predictive accuracy was calculated as sensitivity, specificity, positive and negative predictive values (PPV, NPV) and area under the curve (AUC) on receiver operating characteristic curve. RESULTS: Thirty-six women were included. Weak Dusp6 immunohistochemical expression was significantly associated with increased risk of resistance to treatment, with a RR = 16 (P = 0.0074); predictive accuracy analysis showed sensitivity = 80%, specificity = 90%, PPV = 57.1%, NPV = 96.4%, AUC = 0.85. A weak Dusp6 expression was not significantly associated with the risk of recurrence after an initial regression (RR = 0.4; P = 0.53). CONCLUSION: Weak Dusp6 expression appears as a significant predictor of resistance of AEH/EEC to fertility-sparing treatment, with moderate predictive accuracy. Weak Dusp6 expression is significantly associated with resistance of atypical endometrial hyperplasia or early endometrial cancer to fertility-sparing treatment, with moderate predictive accuracy.

Clinical features of ProMisE groups identify different phenotypes of patients with endometrial cancer.

BACKGROUND: The Proactive Molecular Risk Classifier for Endometrial Cancer (ProMisE) groups has identified four molecular prognostic groups of endometrial cancer (EC): POLE-mutated (POLE-mt), mismatch repair-deficient (MMR-d), p53-abnormal (p53-abn), p53-wild-type (p53-wt). These groups might have different pathogenesis and risk factors, and might occur in different phenotypes of patients. However, these data are still lacking. OBJECTIVE: To provide a clinical characterization of the ProMisE groups of EC. METHODS: A systematic review and meta-analysis was performed by searching seven electronic databases from their inception to December 2020, for all studies reporting clinical characteristics of EC patients in each ProMisE group. Pooled means of age and BMI and pooled prevalence of FIGO stage I and adjuvant treatment in each ProMisE group were calculated. RESULTS: Six studies with 1, 879 women were included in the systematic review. Pooled means (with standard error) and prevalence values were: in the MMR-d group, age = 66.5 ± 0.6; BMI = 30.6 ± 1.2; stage I = 72.6%; adjuvant treatment = 47.3%; in the POLE-mt group, age = 58.6 ± 2.7; BMI = 27.2 ± 0.9; stage I = 93.7%; adjuvant treatment = 53.6%; in the p53-wt group, age = 64.2 ± 1.9; BMI = 32.3 ± 1.4; stage I = 80.5%; adjuvant treatment = 45.3%; in the p53-abn group, age = 71.1 ± 0.5; BMI = 29.1 ± 0.5; stage I = 50.8%; adjuvant treatment = 64.4%. CONCLUSION: The ProMisE groups identify different phenotypes of patients. The POLE-mt group included the youngest women, with the lower BMI and the highest prevalence of stage I. The p53-wt group included patients with the highest BMI. The p53-abn group included the oldest women, with the highest prevalence of adjuvant treatment and the lowest prevalence of stage I. The MMR-d group showed intermediate values among the ProMisE groups for all clinical features.

Tumor mutational burden on cytological samples: A pilot study.

BACKGROUND: Immune-checkpoint inhibitors (ICIs) represent an important treatment option for patients who have advanced stage non-small cell lung cancer (NSCLC). Currently, evaluation of the expression level of programmed death-ligand 1 (PD-L1) has proven highly successful as a positive predictive biomarker for ICIs. In addition to PD-L1, other promising predictive biomarkers are emerging, including high tumor mutational burden (TMB-H). However, measuring TMB-H remains challenging for several reasons, among which is the difficulty in obtaining adequate tissue material from NSCLC patients. There are no data in the current literature regarding the possibility of adopting cell blocks (CBs) for TMB evaluation; therefore, our goal was to evaluate the feasibility of analyzing TMB on CBs. METHODS: For evaluation of differences in run metric parameters, 8 pairs of histological and CB samples from patients with NSCLC were analyzed using the Oncomine Tumor Mutational Load Assay on Ion Torrent S5 GS next-generation sequencing (NGS) platform. RESULTS: Most CBs (6/8, 75.0%) were successfully analyzed by adopting the broad NGS panel approach. CBs provided results similar to those obtained on histological matched specimens in terms of median total reads (7207048.80 vs 7558817.80), median mapped reads (7075753.83 vs 7513822.00), median read lengths (115.50 vs. 113.00), median percentage of reads on-target (97.49% vs. 98.45%), median average reads per amplicon (454.67 vs 476.14), and median uniformity of amplicon coverage (83.52% vs 84.13%). CONCLUSION: In this pilot study, we demonstrated the technical feasibility of assessing TMB on CBs.

Predictive Accuracy of Progesterone Receptor B in Young Women with Atypical Endometrial Hyperplasia and Early Endometrial Cancer Treated with Hysteroscopic Resection plus LNG-IUD Insertion.

STUDY OBJECTIVE: The immunohistochemical expression of isoform B of the progesterone receptor (PRB) has shown promising results in predicting the response of atypical endometrial hyperplasia (AEH) and early endometrial cancer (EEC) to conservative treatment. We aimed to calculate the accuracy of PRB as a predictive marker of conservative treatment outcome in AEH or EEC. DESIGN: Retrospective cohort study. SETTING: University of Naples Federico II, Naples, Italy. PATIENTS: Thirty-six consecutive premenopausal women <45 years of age with AEH (n = 29) or EEC (n = 7) conservatively treated from January 2007 to June 2018 were retrospectively assessed. INTERVENTIONS: All patients had been treated with hysteroscopic resection plus levonorgestrel-releasing intrauterine device insertion and followed for at least 1 year. The immunohistochemical expression of PRB was separately assessed in the glands and stroma of the lesion and dichotomized as "weak" or "normal." MEASUREMENT AND MAIN RESULTS: The treatment outcomes considered were (1) treatment failure (i.e., a combined outcome including no regression or recurrence); (2) no regression; and (3) recurrence. The predictive accuracy of PRB immunohistochemistry was assessed by calculating sensitivity (SE), specificity (SP), and area under the receiver operating characteristic curve (AUC). A weak glandular PRB expression showed SE = 70%, SP = 77%, and AUC = 0.74 for treatment failure; SE = 66.7%, SP = 70%, and AUC = 0.68 for no regression; and SE = 75%, SP = 68.8%, and AUC = 0.72 for recurrence. A weak stromal PRB expression showed SE = 100%, SP = 53.8%, and AUC = 0.77 for treatment failure; SE = 100%, SP = 46.7%, and AUC = 0.73 for no regression; and SE = 100%, SP = 43.8%, and AUC = 0.72 for recurrence. CONCLUSION: A weak stromal PRB expression is a highly sensitive predictive marker of both no response and recurrence of AEH and EEC conservatively treated.

PRMT5 silencing selectively affects MTAP-deleted mesothelioma: In vitro evidence of a novel promising approach.

Malignant mesothelioma (MM) is an aggressive asbestos-related cancer of the serous membranes. Despite intensive treatment regimens, MM is still a fatal disease, mainly due to the intrinsic resistance to current therapies and the lack of predictive markers and new valuable molecular targets. Protein arginine methyltransferase 5 (PRMT5) inhibition has recently emerged as a potential therapy against methylthioadenosine phosphorylase (MTAP)-deficient cancers, in which the accumulation of the substrate 5'-methylthioadenosine (MTA) inhibits PRMT5 activity, thus sensitizing the cells to further PRMT5 inhibition. Considering that the MTAP gene is frequently codeleted with the adjacent cyclin-dependent kinase inhibitor 2A (CDKN2A) locus in MM, we assessed whether PRMT5 could represent a therapeutic target also for this cancer type. We evaluated PRMT5 expression, the MTAP status and MTA content in normal mesothelial and MM cell lines. We found that both administration of exogenous MTA and stable PRMT5 knock-down, by short hairpin RNAs (shRNAs), selectively reduced the growth of MTAP-deleted MM cells. We also observed that PRMT5 knock-down in MTAP-deficient MM cells reduced the expression of E2F1 target genes involved in cell cycle progression and of factors implicated in epithelial-to-mesenchymal transition. Therefore, PRMT5 targeting could represent a promising new therapeutic strategy against MTAP-deleted MMs.

Multiplex fluorescence in situ hybridisation to detect anaplastic lymphoma kinase and ROS proto-oncogene 1 receptor tyrosine kinase rearrangements in lung cancer cytological samples.

AIMS: Several predictive biomarkers of response to specific inhibitors have become mandatory for the therapeutic choice in non-small-cell lung cancer (NSCLC). In most lung cancer patients, the biological materials available to morphological and molecular diagnosis are exclusively cytological samples and minimum tumour wastage is necessary. Multiplex fluorescence in situ hybridisation (mFISH) to detect simultaneously ALK-rearrangement and ROS1-rearrangement on a single slide could be useful in clinical practice to save cytological samples for further molecular analysis. In this study, we aim to validate diagnostic performance of multiplex ALK/ROS1 fluorescence in situ hybridisation (FISH) approach in lung adenocarcinoma cytological series compared with classic single break apart probes. METHODS: We collected a series of 61 lung adenocarcinoma cytological specimens enriched in tumours harbouring ALK-rearrangement and ROS1-rearrangement. ALK and ROS1 status were previously assessed by classic FISH test using single break apart probes and immunohistochemistry. Study population was composed of 6 ALK-positive, 2 ROS1-positive and 53 ALK/ROS1-wild type. All specimens were analysed by multiplex FISH assay using FlexISH ALK/ROS1 DistinguISH Probe Zytovision. RESULTS: The dual ALK/ROS1 FISH probe test results were fully concordant with the results of previous single ALK and ROS1 FISH tests on two different slides. 6 ALK-positive and 2 ROS1-positive were confirmed through multiplex FISH test, without false-positive and false-negative results. Multiplex ALK/ROS1 FISH test results agreed with immunohistochemistry assay staining results. CONCLUSION: Multiplex ALK/ROS1 FISH probe test is a useful tool to detect simultaneously ALK-rearrangement and ROS1-rearrangement on a single slide in cytological specimens with a small amount of biomaterial.

Heterogeneity of PD-L1 Expression in Lung Mixed Adenocarcinomas and Adenosquamous Carcinomas.

Immune checkpoint inhibitors against programmed cell death protein 1/programmed death-ligand 1 (PD-L1) have proven to be remarkably effective in non-small cell lung cancer. PD-L1 represents a predictive biomarker in lung cancer, although its heterogenous expression represents an emerging challenge for accurate biomarker-based patient selection. Lung adenocarcinomas (ADCs) show a high rate of intratumor morphologic heterogeneity that may reflect a heterogenous molecular and immunophenotypic profile. The aim of our study was to analyze the expression of PD-L1 in different intratumor subtypes and/or growth patterns in a series of mixed adenocarcinomas (mADCs) and adenosquamous lung carcinomas (AdSqLCs). As many as 73 mADCs and 6 AdSqLCs were selected. Comprehensive histologic subtyping was performed, and PD-L1 expression was assessed by immunohistochemistry assay using different primary antibodies and automated immunostainers. Overall, PD-L1 expression was observed in 37 of 79 cases (39.2%) (31 mADCs and all AdSqLCs). PD-L1 expression was heterogenous in 22 of 37 PD-L1-positive cases (23.2% mADC and 83% AdSqLC). PD-L1 expression was observed more frequently in ADC with solid pattern. Heterogeneity of PD-L1 expression was significantly related to the presence of micropapillary (P=0.028) and solid (P=0.017) patterns. All PD-L1-positive cases were epidermal growth factor receptor wild-type, 2 cases harbored concomitantly PD-L1 expression and ALK rearrangement. Our data suggest that PD-L1 expression is quite heterogenous in mADCs and AdSqLCs, partly contributing to explaining the discrepant results between biopsy and surgical resections and discordant clinical effectiveness in regard to PD-L1-positive or negative ADC diagnosed on cytology/small biopsy.