ESGO-ESMO-ESP consensus conference recommendations on ovarian cancer: pathology and molecular biology and early, advanced and recurrent disease

The European Society of Gynaecological Oncology, the European Society for Medical Oncology (ESMO) and the European Society of Pathology held a consensus conference (CC) on ovarian cancer on 15-16 June 2022 in Valencia, Spain. The CC panel included 44 experts in the management of ovarian cancer and pathology, an ESMO scientific advisor and a methodologist. The aim was to discuss new or contentious topics and develop recommendations to improve and harmonise the management of patients with ovarian cancer. Eighteen questions were identified for discussion under four main topics: (i) pathology and molecular biology, (ii) early-stage disease and pelvic mass in pregnancy, (iii) advanced stage (including older/frail patients) and (iv) recurrent disease. The panel was divided into four working groups (WGs) to each address questions relating to one of the four topics outlined above, based on their expertise. Relevant scientific literature was reviewed in advance. Recommendations were developed by the WGs and then presented to the entire panel for further discussion and amendment before voting. This manuscript focuses on the recommendation statements that reached a consensus, their voting results and a summary of evidence supporting each recommendation.

Recommendations for the use of next-generation sequencing in patients with metastatic cancer in the Asia-Pacific region: a report from the APODDC working group

INTRODUCTION

Next-generation sequencing (NGS) diagnostics have shown clinical utility in predicting survival benefits in patients with certain cancer types who are undergoing targeted drug therapies. Currently, there are no guidelines or recommendations for the use of NGS in patients with metastatic cancer from an Asian perspective. In this article, we present the Asia-Pacific Oncology Drug Development Consortium (APODDC) recommendations for the clinical use of NGS in metastatic cancers.

METHODS

The APODDC set up a group of experts in the field of clinical cancer genomics to (i) understand the current NGS landscape for metastatic cancers in the Asia-Pacific (APAC) region; (ii) discuss key challenges in the adoption of NGS testing in clinical practice; and (iii) adapt/modify the European Society for Medical Oncology guidelines for local use. Nine cancer types [breast cancer (BC), gastric cancer (GC), nasopharyngeal cancer (NPC), ovarian cancer (OC), prostate cancer, lung cancer, and colorectal cancer (CRC) as well as cholangiocarcinoma and hepatocellular carcinoma (HCC)] were identified, and the applicability of NGS was evaluated in daily practice and/or clinical research. Asian ethnicity, accessibility of NGS testing, reimbursement, and socioeconomic and local practice characteristics were taken into consideration.

RESULTS

The APODDC recommends NGS testing in metastatic non-small-cell lung cancer (NSCLC). Routine NGS testing is not recommended in metastatic BC, GC, and NPC as well as cholangiocarcinoma and HCC. The group suggested that patients with epithelial OC may be offered germline and/or somatic genetic testing for BReast CAncer gene 1 (BRCA1), BRCA2, and other OC susceptibility genes. Access to poly (ADP-ribose) polymerase inhibitors is required for NGS to be of clinical utility in prostate cancer. Allele-specific PCR or a small-panel multiplex-gene NGS was suggested to identify key alterations in CRC.

CONCLUSION

This document offers practical guidance on the clinical utility of NGS in specific cancer indications from an Asian perspective.

The effect of inhibition of receptor tyrosine kinase AXL on DNA damage response in ovarian cancer

AXL is a receptor tyrosine kinase that is often overexpressed in cancers. It contributes to pathophysiology in cancer progression and therapeutic resistance, making it an emerging therapeutic target. The first-in-class AXL inhibitor bemcentinib (R428/BGB324) has been granted fast track designation by the U.S. Food and Drug Administration (FDA) in STK11-mutated advanced metastatic non-small cell lung cancer and was also reported to show selective sensitivity towards ovarian cancers (OC) with a Mesenchymal molecular subtype. In this study, we further explored AXL's role in mediating DNA damage responses by using OC as a disease model. AXL inhibition using R428 resulted in the increase of DNA damage with the concurrent upregulation of DNA damage response signalling molecules. Furthermore, AXL inhibition rendered cells more sensitive to the inhibition of ATR, a crucial mediator for replication stress. Combinatory use of AXL and ATR inhibitors showed additive effects in OC. Through SILAC co-immunoprecipitation mass spectrometry, we identified a novel binding partner of AXL, SAM68, whose loss in OC cells harboured phenotypes in DNA damage responses similar to AXL inhibition. In addition, AXL- and SAM68-deficiency or R428 treatment induced elevated levels of cholesterol and upregulated genes in the cholesterol biosynthesis pathway. There might be a protective role of cholesterol in shielding cancer cells against DNA damage induced by AXL inhibition or SMA68 deficiency.

Nuclear pCHK1 as a potential biomarker of increased sensitivity to ATR inhibition

Excessive genomic instability coupled with abnormalities in DNA repair pathways induces high levels of 'replication stress' when cancer cells propagate. Rather than hampering cancer cell proliferation, novel treatment strategies are turning their attention towards targeting cell cycle checkpoint kinases (such as ATR, CHK1, WEE1, and others) along the DNA damage response and replicative stress response pathways, thereby allowing unrepaired DNA damage to be carried forward towards mitotic catastrophe and apoptosis. The selective ATR kinase inhibitor elimusertib (BAY 1895344) has demonstrated preclinical and clinical monotherapy activity; however, reliable predictive biomarkers of treatment benefit are still lacking. In this study, using gene expression profiling of 24 cell lines from different cancer types and in a panel of ovarian cancer cell lines, we found that nuclear-specific enrichment of checkpoint kinase 1 (CHK1) correlated with increased sensitivity to elimusertib. Using an advanced multispectral imaging system in subsequent cell line-derived xenograft specimens, we showed a trend between nuclear phosphorylated CHK1 (pCHK1) staining and increased sensitivity to the ATR inhibitor elimusertib, indicating the potential value of pCHK1 expression as a predictive biomarker of ATR inhibitor sensitivity. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Interim analysis from a phase II study of olaparib maintenance with pembrolizumab and bevacizumab in BRCA non-mutated patients with platinum-sensitive recurrent ovarian cancer: APGOT-ov4/ OPEB-01

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Background: The optimal treatment of BRCA wild-type patients with platinum-sensitive recurrent (PSR) ovarian cancer remains controversial. This single arm phase 2 study (OPEB-01) evaluated a triple combination regimen with olaparib, bevacizumab, and pembrolizumab as 2nd-line maintenance treatment in BRCA non-mutated, PSR ovarian cancer. Methods: Women with PSR ovarian cancer who had a partial or complete response to their most recent platinum-based regimen were eligible. Patients received olaparib 300mg PO bid daily, bevacizumab 15mg/kg IV q3w, and pembrolizumab 200mg IV q3w until progressive disease or unacceptable toxicity. The primary endpoint of the study was 6-month PFS rate. A simon 2-stage design was utilized. Target accrual was 22 patients in the first stage; 13 or more patients with non-progressive disease at 6 months was required to proceed to second stage. Results: 22 patients were enrolled at the first stage. Median age was 60 years old and most of the patients (90.9%) had high-grade serous carcinoma. Secondary cytoreductive surgery was performed in 6 (27.3%) patients. The objective response rate (ORR) was 68.2% and the disease control rate (DCR) was 90.9%. At the time of data analysis (data cutoff Jan 19 2022), 20 (90.9%) had non-progressive disease at 6 months. No grade 4 adverse events were reported and no treatment related adverse events leading to treatment discontinuation was observed. Additional correlative data regarding homologous recombination deficiency and PD-L1 will be presented at the meeting. Conclusions: OPEB-01 is the first trial to suggest the potential benefit of triple combination maintenance in BRCA wild-type patients. These combinations showed a manageable safety profile. Accrual is ongoing in the second stage. Clinical trial information: NCT4361370.

Genetic counselling and testing for breast and ovarian cancer in Asia: A multinational survey of unmet needs

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Background: Enabling equitable access to healthcare services among women remains a challenge in Asia. Differences in the presentation and treatment stage contribute to disparities in cancer outcomes. Genetic testing provides accurate risk assessment to help guide personalised preventative and treatment options. However, there is a critical need for research to further our understanding of barriers in leveraging optimal benefits of genetic testing and counselling (GT&C) to address cancer among women. Methods: A team of multinational experts was assembled to form the Asian Consensus and Recommendations on Genetic Testing and Counselling (ACROSS) Consortium to assess the challenges in adoption of GT&C for patients with breast and ovarian cancer in Asia. Critical publications were identified, and a pre-meeting questionnaire was developed. The questionnaire was refined to align with the objectives over iterations, and final approval was obtained from the steering committee. Survey responses were gathered from oncologists from ten countries across Asia. The expert committee discussed the survey results to highlight (1) current knowledge, attitude, and practices; (2) unmet needs and gaps; and (3) recommendations for addressing critical obstacles. Results: Adoption of GT&C for cancer is low in Asia. Lack of time, resources, and access to genetic counsellors are major difficulties faced. In most cases, the practising oncologists provide pre-test genetic counselling and communicate test results. For breast cancer (BC), most experts preferred germline testing only, with few opting for somatic testing if germline testing was negative. The agreement was lower among the ovarian cancer (OC) experts, with advocates for either germline or somatic testing or both. There was a lack of consensus on clinical criteria for selecting suitable candidates for genetic testing and the use of multiple gene panel germline testing. The need for government-aided subsidies and training programmes was highlighted. Conclusions: Recommendations from the expert panel included (1) development of guidelines and criteria to identify candidates suitable for GT&C; (2) training healthcare professionals with required competencies; (3) improving accessibility and affordability; (4) increased patient education and awareness; and (5) adoption of GT&C into the national healthcare system. The consortium agreed that a multifaceted plan of action combining the expertise of clinicians, scientists, and policymakers is required to facilitate uptake of GT&C in Asia. [Table: see text]

A multicenter phase II randomized trial of durvalumab (D) versus physician’s choice chemotherapy (PCC) in patients (pts) with recurrent ovarian clear cell adenocarcinoma (MOCCA/APGOT-OV2/GCGS-OV3)

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Background: The optimal treatment of recurrent ovarian clear cell carcinoma (rOCCC) remains unknown. Prior data suggests rOCCC is a chemo-resistant disease that may respond to programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immune checkpoint inhibition (ICI). We aimed to determine the efficacy of D versus PCC in pts with rOCCC. Methods: In this multicentre, open-label, randomised phase 2 trial, 9 academic centres across Singapore, South Korea and Australia, enrolled rOCCC (determined histologically) and Eastern Cooperative Oncology Group performance status (PS) 0-2 pts, who had recurred after prior platinum-based chemotherapy and had not received more than 4 prior lines of systemic therapy, nor prior ICI therapy. Eligible pts were randomly assigned (2:1), using dynamic block randomization with block size of 6, and stratification by ECOG PS, to receive D (1500mg on day 1, in 28-day cycles) or PCC until disease progression (PD), intolerable toxicity or withdrawal of consent. Pts with PD on PCC were allowed to crossover to D. The primary endpoint was investigator-assessed progression-free survival (PFS) by RECIST version 1.1 and analyses included pts who had commenced at least 1 cycle of study treatment. Results: Between 7 Nov 2017 and 17 Feb 2020, 57 pts were assessed for eligibility, of whom 47 (PS 0-1) were randomly assigned to treatment with D (31 pts) or PCC (16 pts). At the data cut-off date (10 Jan 2022), the median follow-up was 83.0 weeks (IQR: 54.1—97.0) in the PCC group and 107.0 weeks (IQR: 82.7—116.4) in the D group. Median PFS was 7.4 weeks (IQR: 6.0—16.0) in the D group and 14.0 (IQR: 7.0—28.6) in the PCC group (HR 1.5 [95% CI 0.8-2.8], log-rank p = 0.89). The objective response rate (ORR) was 10.7% in pts randomised to D and 18.8% in the PCC group (p = 0.884). Clinical benefit rate (CR/PR/SD for ≥16weeks) was similar for PCC (37.5%) and D (32.1%) (p = 0.756). 9 pts on PCC crossed over to receive D, with 2 of the 8 evaluable pts achieving partial response (PR). When crossover D pts were included, ORR to D was 13.9% (5/36) with a clinical benefit rate of 30.6% (11/36). Median duration of response was 44 weeks for the 3 PCC responders (PR to gemcitabine 24.9wks, PR to liposomal doxorubicin 65.7wks, CR to carboplatin/liposomal doxorubicin 44wks), and 18 weeks (range 2.1-45.3) for the 5 responders to D. Frequency of adverse events (AEs) across all grades was 68.8% for PCC and 38.7% for D. Grade 3/4 AEs were observed in 37.5% of PCC pts and 9.7% of D pts. Conclusions: No significant differences in PFS, ORR or clinical benefit rate were observed between D and PCC treatment in rOCCC. Treatment with D was associated with less grade 3-4 adverse events. Correlative translational analyses to elucidate predictive biomarkers of response and resistance are ongoing. Clinical trial information: NCT03405454.

GAGE mediates radio resistance in cervical cancers via the regulation of chromatin accessibility

Radiotherapy (RT) resistance is a major cause of treatment failure in cancers that use definitive RT as their primary treatment modality. This study identifies the cancer/testis (CT) antigen G antigen (GAGE) as a mediator of radio resistance in cervical cancers. Elevated GAGE expression positively associates with de novo RT resistance in clinical samples. GAGE, specifically the GAGE12 protein variant, confers RT resistance through synemin-dependent chromatin localization, promoting the association of histone deacetylase 1/2 (HDAC1/2) to its inhibitor actin. This cumulates to elevated histone 3 lysine 56 acetylation (H3K56Ac) levels, increased chromatin accessibility, and improved DNA repair efficiency. Molecular or pharmacological disruption of the GAGE-associated complex restores radiosensitivity. Molecularly, this study demonstrates the role of GAGE in the regulation of chromatin dynamics. Clinically, this study puts forward the utility of GAGE as a pre-screening biomarker to identify poor responders at initial diagnosis and the therapeutic potential of agents that target GAGE and its associated complex in combination with radiotherapy to improve outcomes.

The role of homologous recombination deficiency testing in ovarian cancer and its clinical implications: do we need it?

The recognition of homologous recombination deficiency (HRD) as a frequent feature of high-grade serous ovarian cancer (HGSOC) has transformed treatment paradigms. Poly(ADP-ribose) polymerase inhibitors (PARPis), developed based on the rationale of synthetic lethality that predicates antitumor efficacy in tumors harboring underlying HRD, now represents an important class of therapy for HGSOC. Recent data have drawn attention to the assessment of homologous recombination DNA repair (HRR) as a prognostic and predictive biomarker in HGSOC, leading to increasing debate on the optimal means of defining and evaluating HRD, both genotypically and phenotypically. At present, clinical-grade assays such as myChoice CDx and FoundationOne CDx are approved companion diagnostics which can identify patients with HRD-positive HGSOC by diagnosing a 'genomic scar' reflecting underlying genomic instability. Yet despite the rapid maturation of this field, tumoral HRD status has been recognized to be dynamic over time and with treatment pressure. In practice, this means that restoration of HRR through mechanisms of platinum and PARPi resistance are not adequately represented by genomic scar assays, and contribute toward discordance with clinical PARPi response, or lack-thereof. It is thus critical that HRD testing is optimized to address the controversies of diverse HRD testing methodology, appropriate thresholds for HRD identification, and relevant timepoints for HRD testing, in order to realize the potential for PARPis to maximally benefit patients with HGSOC. Here, we discuss the premise of HRD testing in HGSOC, current methodologies for HRD identification and their performance in the clinic, highlight upcoming strategies, and discuss the challenges faced in moving this field forward.

The systemic treatment of recurrent ovarian cancer revisited

Treatment approaches for relapsed ovarian cancer have evolved over the past decade from a calendar-based decision tree to a patient-oriented biologically driven algorithm. Nowadays, platinum-based chemotherapy should be offered to all patients with a reasonable chance of responding to this therapy. The treatment-free interval for platinum is only one of many factors affecting patients' eligibility for platinum re-treatment. Bevacizumab increases the response to chemotherapy irrespective of the cytotoxic regimen and can be valuable in patients with an urgent need for symptom relief (e.g. pleural effusion, ascites). For patients with recurrent high-grade ovarian cancer, which responds to platinum-based treatment, maintenance therapy with a poly(ADP-ribose) polymerase inhibitor can be offered, regardless of the BRCA mutation status. Here we review contemporary decision-making processes in the systemic treatment of relapsed ovarian cancer.

Molecular profiling of metastatic breast cancer (MBC) and target-based therapeutic matching in an Asian tertiary phase I oncology unit

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Background: Somatic profiling of MBC has highlighted actionable mutations and driven trials of matched targeted therapy (tx). Previous phase I studies have reported improved outcomes following matched therapies with tumour molecular profiles. Here, we review next generation sequencing (NGS) and treatment outcomes of Asian MBC patients (pts) in the phase I unit of a tertiary centre. Methods: Pts with MBC referred to a phase I unit underwent NGS (n = 152). Tumour tissue was sequenced via the amplicon based Ion Ampliseq Cancer (IAC) v2 (50 genes) platform from 2014-2017 prior to institutional change to Foundation Medicine 1 (FM1) (324 genes) 2017-2019. Patients were counselled on findings and enrolled onto matched therapeutic trials where available. Results: NGS was successfully performed in 107 pts (IAC 46%, FM1 54%) of which tumour subtypes include hormone receptor positive 63%, triple negative breast cancer (TNBC) 28% and Her2 positive 19%. Median lines of prior tx for MBC was 4 (range 0-12). 89% had prior chemotherapy (CT), 57% prior endocrine therapy (ET). 72/107 (67%) sequenced patients had further treatment and 18 (25%) were matched to tx based on NGS findings (15 clinical trial, 3 off trial). Matching rates on both NGS platforms were similar (IAC 22% vs FM1 28%). Mutated pathways with potential matched tx included PIK3CA/AKT/PTEN (52%), DNA damage response (DRR) (15%), and FGFR (11%) pathways. PIK3 mutations were seen in 43% and associated with higher number of metastatic sites (p = 0.03); most prevalent aberrations were PIK3CA H1047R (41%) and PIK3CA E542K (13%). Matched cases were more heavily pretreated (mean lines of prior tx 5.3 matched vs 3.7, unmatched p = 0.05), and showed a median progression free survival (mPFS) of 24 weeks [w] and clinical benefit rate (complete/partial response or stable disease ≥ 12 weeks) of 53% on matched tx. Comparison by NGS platform showed improved mPFS for matched vs unmatched pts sequenced on FM1 vs IAC (FM1: 26 vs 19w, HR = 0.76 [95% CI: 0.3-1.9]; IAC: 8 vs 12w; HR = 1.21 [95% CI: 0.5-2.8]). Interestingly, 1 pt with SMARCB mutation, reportedly associated with the FGFR pathway, had a PFS of 70w on tx with a pan-FGFR inhibitor after progressing on 3 prior lines of tx (ET and CT). Conclusions: Molecular profiling of MBC in a phase I unit led to matched tx in 25% of cases. Matched pts showed encouraging mPFS with a suggestion of benefit in those matched after sequencing on a broader gene panel (FM1).

Clinical efficacy and molecular effects of lenvatinib (Len) and letrozole (Let) in hormone receptor-positive (HR+) metastatic breast cancer (MBC)

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Background: Preclinical studies show cross talk between RET and estrogen receptor, with at least additive treatment (Tx) effect of Len, a RET inhibitor, with Let. Our previous work concluded a recommended phase 2 dose (RP2D) of Len 14mg daily and Let 2.5mg daily (Lim, ASCO 2019). We present efficacy data from dose escalation and expansion cohorts. Methods: Safety, tolerability and efficacy data of MBC patients in both dose escalation (Len dose level 1 [DL]:20mg, DL -1:16mg and DL -2:14mg) and expansion (Len 14mg) cohort of this phase Ib/II study of combination Len+Let study was analysed. Patients were treated with single-agent Len for 2 weeks, followed by Len+Let until disease progression (PD). Serial tumor biopsies at baseline, after Len alone, 4 weeks post Len+Let, and upon PD, were sequenced for 440 genes with the ACTOnco+ platform. Results: A total of 33 pts (DL1 6pts, DL-1 6pts, DL-2 + expansion 21pts) with median 5 lines of prior Tx (range 0-11) were enrolled; 87.9%, 75.8%, and 75.8% had prior endocrine therapy (ET), ET+CDK4/6 inhibitor (i), and chemotherapy (CT) respectively. Objective response rate (ORR), disease control rate (DCR) ≥6 months (m), median duration of response (DOR), and percentage progression-free (PPF) at 12m were 33.3%, 45.5%, 11.5m (range 6.3-22.4), and 27.2% respectively. Among patients who previously progressed on CDK4/6i (n = 25), ORR, DCR ≥6m, median DOR, and PPF at 12m were 24.0%, 40.0%, 13.7m (range 6.3-18.2), and 12.0% respectively. Of note, 3/25 (12%) patients had durable response to Len+Let lasting ≥12m, despite having only modest PFS on ET+CDK4/6i (3, 7, and 12 months respectively). Most frequent all-grade toxicities (tox) were HTN (n = 15, G3:15), hypothyroidism (n = 20, G3:0) and fatigue (n = 13, G3:2), with no G4/5 tox. No new toxicity signals were observed compared to dose escalation phase. Pre-treatment tumor molecular profiling showed responders to be more likely to harbor NEFH, USH2A and PTCH1 mutations, while non-responders were more likely to carry PIK3R1, APC and PALB2 mutations. Sequencing of serial biopsies showed downregulation of BRD4, PTCH1, KIT, NTRK1 and CREBBP after Len treatment. Conclusions: Len+Let showed significant anti-tumor activity with meaningful duration of response, even in pts who failed prior CT or ET+CDK4/6i. The results support further investigation in randomized studies. Tumor profiling identified mutations associated with response and insights on molecular effects of lenvatinib. Clinical trial information: NCT02562118 .

Clinical outcomes of MSI-high (MSI-H) versus stable (MSS) endometrial carcinoma (EC) after front-line platinum chemotherapy and subsequent matched therapy

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Background: Precision oncology approaches in EC patients (pts) are evolving with emerging targeted therapy. We reviewed the effect of genomic findings on treatment choice and outcome in an Asian EC cohort. Methods: Recurrent or metastatic ECs were prospectively profiled with next-generation sequencing (NGS) and relevant immunohistochemistry. Clinical data were collected to assess outcomes. Results: Between 12/2014 to 12/2019, 51 Asian EC pts of endometrioid (26/51), serous (7/51), carcinosarcoma (4/51), clear cell (4/51) and mixed (10/51) histology were enrolled. 35/51(69%) of tumors were high grade. The median age at diagnosis was 56 (range 37-77), and the median lines of treatment received was 3 (range 1-8). 45/51(88%) of pts had successful NGS profiling, 31/45(69%) using FoundationOne CDx, and 14/45 (31%) on an in-house platform. Frequent mutations (>20%) occurred in PTEN (60%), PIK3CA (49%), TP53 (46%), ARID1A (27%), CTNNB1 (24%) and KRAS (22%). There were 12/51(24%) MSI-H, 25/51(49%) MSS, and 14/51(27%) MSI-unknown tumors. The 6 mth progression free survival (PFS) rate for MSS versus MSI-H pts treated with front-line carboplatin+paclitaxel (CP) was 83% versus 50% (RR 1.67, fisher’s exact 2-sided p=0.09), with a shorter median PFS after 1st line CP for MSI-H versus MSS pts (median 5.2 mth vs. 8.3 mth, not sig). Upon progression, 29/51(57%) of pts were matched to therapy based on tumor profiles. Of these, 7/29(24%), 13/29(45%) and 9/29(31%) matched to anti-PD1/PD-L1, endocrine therapy and other targeted therapy, respectively. Among 7 MSI-H pts matched to anti-PD1/PD-L1 therapy, median PFS was 14.6 mth (95% CI 0.4-29), and objective response rate was 57%(4/7). In subsequent-line, matching to endocrine therapy (HR 4.3 95% CI 0.95-19.0, p=0.06) or other targeted therapy (HR 5.1, 95% CI 1.1-24.5, p=0.04) was associated with worse PFS compared to anti-PD1/PD-L1 therapy. Despite a short median PFS after front-line CP, median overall survival (OS) was not reached for MSI-H pts, compared to 38 mth (95% CI 30.7-46.0) for MSS and MSI-unknown pts. Conclusions: MSI-H EC pts appear to have shorter PFS to front-line CP chemotherapy compared with MSS pts, but may derive durable responses from immunotherapy in subsequent-line therapy. Early use of immunotherapy in advanced MSI-H EC pts should be considered. Further optimisation of therapy is urgently needed in advanced MSS EC.

Analysis of gene expression signatures identifies prognostic and functionally distinct ovarian clear cell carcinoma subtypes

Background

Ovarian clear cell carcinoma (OCCC) is a histological subtype of epithelial ovarian cancer (EOC) with distinct pathological, biological, and molecular features. OCCCs are more resistant to conventional treatment regimen of EOC and have the worst stage-adjusted prognosis amongst EOC subtypes. As the OCCC incidence rate in Asian populations has significantly increased in recent decades, it is critical to elucidate its molecular features that could lead to OCCC-tailored therapeutic strategies.

Methods

Gene expression profiles of 222 OCCC were analyzed by hierarchical clustering and statistical analyses.

Findings

We identified two OCCC gene expression subtypes: EpiCC—epithelial-like, which is associated with early-stage disease, with a relatively higher rate of gene mutations in the SWI/SNF complex; and MesCC—mesenchymal-like, associated with late-stage and higher enrichment of immune-related pathway activity. Genetic, copy number and transcriptomic analyses showed that both EpiCC and MesCC carried OCCC-associated aberrations. The EpiCC/MesCC classification was reproducible in validation cohorts and OCCC cell lines. MesCC tumors had a poorer progression-free survival (PFS) than EpiCC tumors (HR: 3·0, p = 0·0006). Functional assays in cell lines showed that the MesCC subtype was more proliferative and more anoikis-resistant than the EpiCC. By applying the EpiCC/MesCC classification to the TCGA renal clear cell carcinoma cohort, our results indicated interoperability of the subtyping scheme, and revealed preferential drug response of MesCC to bevacizumab.

Interpretation

The EpiCC/MesCC classification shows promise for prognostic and therapeutic stratification in OCCC patients and warrants further investigation in the context of OCCC gene expression subtype-tailored treatment strategies.

Clinical validation of GAGE family protein as a biomarker for radiotherapy resistance in cervical cancer

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Background: Cervical cancer is the 4th most common cancer in females. Treatment recommendation for locally advanced cervical cancer includes concurrent chemo-radiotherapy (RT) followed by brachytherapy. However, primary treatment failure is not uncommon and is attributed to RT resistance. In view of RT-associated complications, identification of RT-resistant groups at diagnosis will help to minimize exposure to unnecessary toxicities. Methods: Our initial studies analyzing the genetic profile of RT-sensitive and RT-resistant tumours from xenograft models have identified the GAGE-family protein as a genetic marker that is selectively upregulated in RT-resistant xenograft tumours in vitro & in animal studies and is associated with more aggressive phenotypes of these tumors. To clinically validate these findings, we carried out a pilot study on 8 patients and also analyzed GAGE-family protein levels in retrospective study samples obtained from initial biopsy samples from from patients who have completed chemoRT and brachytherapy for cervical cancer to correlate their initial GAGE-family protein levels with treatment response. Results: Immuno-histological staining of pathology samples from 8 patients in our pilot study have shown that those with a higher expression of GAGE-family protein at mRNA and protein levels are more resistant to standard RT. Our retrospective analysis of 43 cervical cancer biopsy samples showed significantly elevated levels of GAGE-family protein mRNA ( P= 0.0028) and GAGE-family protein intensity score ( P= 0.026) in the 20 patients who were found to be resistant to standard definitive RT on subsequent follow-up compared to 23 patients who responded well. Median follow-up was 42 months. Conclusions: GAGE-family protein mRNA and protein expressions are elevated in patients resistant to standard definitive RT. We aim to develop a classification system to stratify patients into responders versus poor responders based on their GAGE-family protein levels at initial diagnosis in order to personalize treatment regimen whereby good responders can be treated with reduced RT dose and poor responders can receive escalated RT dose and further therapies in order to improve outcome.

A phase Ib/II trial of lenvatinib (len) and letrozole (let) incorporating pharmacodynamics studies in postmenopausal women with hormone receptor positive (HR+) locally advanced/metastatic breast cancer (LABC/MBC)

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Background: Endocrine blockade (EB) is standard of care for patients (pts) with HR+ LABC/MBC. RET over-expression (RET+) occurs in up to 75% of HR+ breast cancers and is a postulated mechanism of endocrine resistance. Preclinical studies show cross talk between RET and estrogen receptor, and at least additive treatment (Tx) effect of Len+EB. Methods: We performed a phase Ib trial (3+3 dose escalation) to study safety, tolerability, pharmacodynamics and efficacy of Len+Let. Both drugs were given as continuous daily dosing with 2 weeks (wks) of Len alone, followed by Len+Let for 12 wks then surgery (LABC), or till disease progression (PD) (MBC). Serial tumor biopsies (n = 15) were done at baseline, after Len alone, 4 wks post Len+Let, and at surgery [LABC] / upon PD [MBC]. Results: 16 pts were treated (4 LABC, 12 MBC); Among MBC pts, median lines of prior Tx was 3 (range 0-10); 84.6%, 66.7%, and 58.3% had prior EB, EB+CDK4/6 inhibitor (i), and chemotherapy (CT) respectively. At dose level (DL) 1, 2/4 pts had dose-limiting toxicities (DLT). There was no DLT at DL-1, but 6/6 pts needed dose reductions (DR), with 4/6 DR within 6 wks of Len+Let (3 G3 hypertension [HTN], 1 G3 wound pain), deeming DL-1 intolerable. At DL-2, 0/6 pts had DLT; this was declared recommended phase 2 dose (RP2D). Most frequent G3 toxicities (tox) were HTN (6/16), proteinuria (2/16) and palmar-plantar erythrodysesthesia (PPE) (2/16), with no G4/5 tox. Len+Let was active with 93.8% overall disease control rate (DCR) (50.0% partial response [PR], 43.8% stable disease [SD]). Among MBCts (8/12 had prior EB+CDK4/6i), DCR ≥12 wks was 91.7%; 1 pt had sustained PR for 48 wks and 1 ongoing PR at 40 wks. 9/16 pts had RET+ tumors on immunohistochemistry at baseline, and 66.7% showed down-regulation with Tx (RECIST: 4 PR, 2 SD). Conclusions: Len+Let showed significant anti-tumor activity, even in pts who failed prior CT or EB+CDK4/6i. RP2D of 14mg Len and 2.5mg Let is tolerated with efficacy; dose expansion is currently underway. Clinical trial information: NCT02562118. [Table: see text]

First-in-human trial of the oral ataxia telangiectasia and Rad3-related (ATR) inhibitor BAY 1895344 in patients (pts) with advanced solid tumors

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Background: The ATR kinase is a key regulator of the DNA damage response (DDR) machinery, activated by DNA damage and replication stress. BAY 1895344 is a novel, potent, and selective ATR inhibitor with anti-tumor activity in preclinical models with DDR defects. Methods: Pts with advanced metastatic solid tumors resistant or refractory to standard treatment, with and without DDR defects, received BAY 1895344 BID, 3 days (d) on/4 d off continuously in 3-weekly cycles. Results: As of December 20, 2018, 18 pts with colorectal (4), breast (3), prostate (2), and ovarian (2) cancers were enrolled across 6 cohorts (5 mg, 10 mg, 20 mg, 40 mg, 60 mg, and 80 mg BID). Median prior lines of treatment was 5. No dose-limiting toxicities (DLTs) were reported in the 5-40 mg cohorts. 2/3 pts had DLTs in the 80 mg cohort (grade [G] 4 neutropenia, G4 neutropenia and G4 thrombocytopenia) and 2/7 had DLTs in the 60 mg cohort (G4 neutropenia, G2 fatigue). 40 mg BID 3 on/4 off was defined as the maximum tolerated dose. Most common treatment-emergent adverse events included anemia, neutropenia, nausea, and fatigue. Pharmacokinetics appeared dose proportional. Pharmacodynamic analyses showed modulation of pH2AX and/or pKAP1 in paired tumor biopsies at exposures associated with preclinical anti-tumor activity. In 13 pts with and without DDR defects treated at dose levels ≥40 mg BID, the objective response rate was 30.7%, including 2/2 pts at 40 mg (appendix and urothelial cancer), 1/8 pts at 60 mg (breast), and 1/3 pts at 80 mg (endometrial). All responders had ATM protein loss of expression and/or ATM mutation; median treatment duration was 347 d (range 293-364 d). A BRCA1-mutant, olaparib-resistant ovarian cancer pt (60 mg) had a CA125 response and stable disease >10 months. 41 additional pts have been enrolled in ongoing expansion cohorts in cancers with DDR defects (prostate, breast, gynecologic, colorectal) or ATM protein loss (all comers) with responses observed. Conclusions: The ATR inhibitor BAY 1895344 is tolerated at biologically active doses with anti-tumor activity against cancers with certain DDR defects, including ATM protein loss. Clinical trial information: NCT03188965.

Decoding transcriptomic intra-tumour heterogeneity to guide personalised medicine in ovarian cancer

The evaluation of intra-tumour heterogeneity (ITH) from a transcriptomic point of view is limited. Single-cell cancer studies reveal significant genomic and transcriptomic ITH within a tumour and it is no longer adequate to employ single-subtype assignment as this does not acknowledge the ITH that exists. Molecular assessment of subtype heterogeneity (MASH) was developed to comprehensively report on the composition of all transcriptomic subtypes within a tumour lesion. Using MASH on 3431 ovarian cancer samples, correlation and association analyses with survival, metastasis and clinical outcomes were performed to assess the impact of subtype composition as a surrogate for ITH. The association was validated on two independent cohorts. We identified that 30% of ovarian tumours consist of two or more subtypes. When biological features of the subtype constituents were examined, we identified significant impact on clinical outcomes with the presence of poor prognostic subtypes (Mes or Stem-A). Poorer outcomes correlated with having higher degrees of poor prognostic subtype populations within the tumour. Subtype prediction in several independent datasets reflected a similar prognostic trend. In addition, paired analysis of primary and recurrent/metastatic tumours demonstrated Mes and/or Stem-A subtypes predominated in recurrent and metastatic tumours regardless of the original primary subtype. Given the biological and prognostic value in delineating individual subtypes within a tumour, a clinically applicable MASH assay using NanoString^® technology was developed as a classification tool to comprehensively describe constituents of molecular subtypes. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Tumor molecular profiling of responders and non-responders following pembrolizumab monotherapy in chemotherapy resistant advanced cervical cancer

Optimal treatment for advanced cervical cancer after first line chemotherapy remains undefined. Immune checkpoint inhibition with pembrolizumab, a programmed cell death protein 1(PD-1) inhibitor, is under investigation. We analyzed the micro-environmental and molecular genetic profile of tumors from 4 patients with metastatic cervical cancer treated with off-label second-line pembrolizumab in an effort to identify predictive biomarkers. All patients received 2 mg/kg of pembrolizumab, 3-weekly until disease progression. Immunohistochemistry(IHC) for PD-1, PD-L1, CD3 and CD8, as well as next generation sequencing (NGS) for 50 cancer-related genes were performed on tumor samples. All patients tolerated treatment well with no discontinuation of treatment due to toxicity. One patient experienced dramatic and prolonged partial response, and remains stable on pembrolizumab with a progression free survival (PFS) of 21 months at the time of reporting of this series. Three patients experienced disease progression as best response. In the exceptional responder, there was no tumoral expression of PD-L1, however, combined positive score (CPS) for PD-L1 was 1 and we identified somatic mutations in ERBB4(R612W), PIK3CA(E542K) and RB1(E365K). In 2 patients, despite progressive disease defined by RECIST v1.1, symptom stabilization on pembrolizumab was observed. The tumors of both patients had PD-1 expression in ≥1% of stromal lymphocytes. All patients with response or clinical benefit had CPS for PD-L1 ≥ 1. NGS revealed PIK3CA mutations in 3 tumors. Pembrolizumab is a promising therapeutic option in advanced cervical cancer. Further evaluation of biomarkers may guide optimal patient selection.

Whole exome sequencing (WES) of multiple spatially distinct biopsies from single metastatic lesions to evaluate tumour heterogeneity and identify actionable truncal mutations (ATMs) in patients (pts) with advanced solid malignancies using a radiologically-guided single-pass percutaneous technique

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Background: Genomic profiling of single core biopsies (bx) are confounded intratumoral heterogeneity, resulting in sampling bias. We explored the use of a novel technique to obtain multiple bx from single metastatic lesion in pts to evaluate heterogeneity and identify therapeutic ATM. Methods: 15 pts (5 NSCLC; 3 ovarian; 2 colon, 2 uterine and 1 breast, cervix and HCC) with biopsiable lesions were identified. Using a single pass radiologically guided percutaneous bx technique, we obtained multiple spatially distinct core bx samples from a single metastatic lesion. Each bx underwent DNA extraction and WES using the NextSeq500. Results: Median of 4 core bx were obtained from each lesion. Complication rate utilizing this technique was 0%. 2 pts were omitted from analysis due to poor quality DNA with 13 pts successfully sequenced. In 1 pt, only 2 of 4 cores were successfully sequenced. The median amounts of total and non-synonymous variants were 137 (27-1286) and 66 (10-649) respectively. The median (range) filtered variants detected in 1/4, 2/4, 3/4, and 4/4 bx cores was 63(16-91)%, 5(1-65)%, 4(0-30)% and 26(0-63)% respectively, suggesting significant subclonal diversity within a single lesion. ATMs were identitified in 8/13 pts. 4/13 pts (31%) had no ATM across all 4 cores. 3 pts received therapy with inhibitors targeting ATMs. A pt with AKT1_E17K ATM received an AKT inhibitor with 21% tumour shrinkage and PFS 6.1 mths. 2 NSCLC pts harbouring an EGFR_T790M ATM were treated with an EGFRT790M specific TKI. 1 withdrew due to toxicity after 2mths and another had PFS > 16.5 mths. Tumour mutational burden (TMB) was consistent across multiple bx from each lesion. A NSCLC pt with the highest TMB received a checkpoint inhibitor with ongoing > 4 mths stable disease. Conclusions: Utilizing a single pass radiologically guided techniqueto obtainmultiple bx is feasible, safe and informative. This allows reconstruction of a tumour’s subclonal genomic architecture, providing insights into mutational heterogeneity and help guide therapy.

Phase II clinical and molecular trial of oral ENMD-2076 in clear cell ovarian cancer (CCOC): A study of the Princess Margaret phase II consortium

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Background: CCOC is a rare chemoresistant subtype of OC. ENMD-2076 is an oral multi-target kinase inhibitor with antiangiogenic/antiproliferative profile; selective activity against the mitotic kinase Aurora A and VEGFRs, FGFRs. Methods: This is a multi-center Phase II study of ENMD-2076 in pts with recurrent CCOC and prior platinum. Primary endpoints were ORR and 6-m PFS rate. Correlative analyses include ARID1A, PTEN expression by IHC and genome sequencing by custom capture library of 555 genes. Results: Completed study enrolled 40 pts – 37 evaluable, median age of 54 (39-78). 12 pts (31%) received prior radiation and 24 (62%), 11 (28%), 4 (10%) had 1, 2 or 3 lines of chemotherapy. Archival tissue was available for 36/37 pts. Best response was PR for 2 pts (1 unconfirmed), SD for 25 (68%) and PD for 10 (26%) pts. Median PFS was 3.7 months (m) (95%CI: 3.4-4.4). ENMD was well tolerated with main related AE: hypertension (21 pts - 8 G3), nausea (18 pts -1 G3) and diarrhea (17 pts - 4 G3). By IHC, median PFS (95%CI) in ARID1A loss (19 pts) was 4.1m (3.5-10.3) vs 3.6m (1.7-3.9) in ARID1A positive (17 pts) (p = 0.024). Whilst, by IHC, PTEN was loss in 20 pts; intact in 10 and heterogeneous in 6 pts; no difference in PFS was observed. By PI3KCA mutation status, median PFS (95%CI) in wild-type (WT) (12 pts) was 5m (3.4-19.3) vs 3.7m (167-4.4) in mutated group (20 pts) (p = 0.038). Molecular profiling showed variants in PI3KCA (27%), ARID1A (26%), TP53 (7%), BRIP1 (7%), ATM (11%), BRCA1 (5%), BRCA2 (3%), RAD50 (3%), PABL2 (1%), RAD51C (1%), FANCA (1%), CTNNB1 (3%).The patient with the longest treatment duration (22m) was PTEN WT, diploid PTEN, putative bi-allelic inactivation of ARID1A. Conclusions: The PFS at 6 months was 20% for the evaluable patients, 31% in ARID1A loss and 12% in ARID1A positive patients. Loss of ARID1A, a known negative prognostic factor, was correlated with better PFS on ENMD-2076. Additional molecular profiling of the baseline biopsy material is underway. Clinical trial information: NCT01914510.

Update on immune checkpoint inhibitors in gynecological cancers

In recent years, progress in our understanding of immune-modulatory signaling pathways in immune cells and the tumor microenvironment (TME) has led to rejuvenated interest in cancer immunotherapy. In particular, immunotherapy targeting the immune checkpoint receptors such as cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), programmed cell-death 1 (PD-1), and programmed cell-death ligand 1 (PD-L1) have demonstrated clinical activity in a wide variety of tumors, including gynecological cancers. This review will focus on the emerging clinical data on the therapeutic role of immune checkpoint inhibitors, and potential strategies to enhance the efficacy of this class of compounds, in the context of gynecological cancers. It is anticipated that future biomarker-directed clinical trials will provide further insights into the mechanisms underlying response and resistance to immunotherapy, and help guide our approach to designing therapeutic combinations that have the potential to enhance the benefit of immunotherapy in patients with gynecologic cancers.

Limb Hypothermia for Preventing Paclitaxel-Induced Peripheral Neuropathy in Breast Cancer Patients: A Pilot Study

BACKGROUND

Peripheral neuropathy (PN) due to paclitaxel is a common dose-limiting toxicity with no effective prevention or treatment. We hypothesize that continuous-flow limb hypothermia can reduce paclitaxel-induced PN.

PATIENTS AND METHODS

An internally controlled pilot trial was conducted to investigate the neuroprotective effect of continuous-flow limb hypothermia in breast cancer patients receiving weekly paclitaxel. Patients underwent limb hypothermia of one limb for a duration of 3 h with every paclitaxel infusion, with the contralateral limb used as control. PN was primarily assessed using nerve conduction studies (NCSs) before the start of chemotherapy, and after 1, 3, and 6 months. Skin temperature and tolerability to hypothermia were monitored using validated scores.

RESULTS

Twenty patients underwent a total of 218 cycles of continuous-flow limb hypothermia at a coolant temperature of 22°C. Continuous-flow limb hypothermia achieved mean skin temperature reduction of 1.5 ± 0.7°C and was well tolerated, with no premature termination of cooling due to intolerance. Grade 3 PN occurred in 2 patients (10%), grade 2 in 2 (10%), and grade 1 in 12 (60%). Significant correlation was observed between amount of skin cooling and motor nerve amplitude preservation at 6 months (p < 0.0005). Sensory velocity and amplitude in the cooled limbs were less preserved than in the control limbs, but the difference did not attain statistical significance. One patient with a history of diabetes mellitus had significant preservation of compound muscle action potential in the cooled limb on NCS analysis.

CONCLUSION

This study suggests that continuous limb hypothermia accompanying paclitaxel infusion may reduce paclitaxel-induced PN and have therapeutic potential in select patients and warrants further investigation. The method is safe and well tolerated.

CSIOVDB: a microarray gene expression database of epithelial ovarian cancer subtype

Databases pertaining to various diseases provide valuable resources on particular genes of interest but lack the molecular subtype and epithelial-mesenchymal transition status. CSIOVDB is a transcriptomic microarray database of 3,431 human ovarian cancers, including carcinoma of the ovary, fallopian tube, and peritoneum, and metastasis to the ovary. The database also comprises stroma and ovarian surface epithelium from normal ovary tissue, as well as over 400 early-stage ovarian cancers. This unique database presents the molecular subtype and epithelial-mesenchymal transition status for each ovarian cancer sample, with major ovarian cancer histologies (clear cell, endometrioid, mucinous, low-grade serous, serous) represented. Clinico-pathological parameters available include tumor grade, surgical debulking status, clinical response and age. The database has 1,868 and 1,516 samples with information pertaining to overall and disease-free survival rates, respectively. The database also provides integration with the copy number, DNA methylation and mutation data from TCGA. CSIOVDB seeks to provide a resource for biomarker and therapeutic target exploration for ovarian cancer research.

Low Levels of NDRG1 in Nerve Tissue Are Predictive of Severe Paclitaxel-Induced Neuropathy

Introduction

Sensory peripheral neuropathy caused by paclitaxel is a common and dose limiting toxicity, for which there are currently no validated predictive biomarkers. We investigated the relationship between the Charcot-Marie-Tooth protein NDRG1 and paclitaxel-induced neuropathy.

Methods/Materials

Archived mammary tissue specimen blocks of breast cancer patients who received weekly paclitaxel in a single centre were retrieved and NDRG1 immunohistochemistry was performed on normal nerve tissue found within the sample. The mean nerve NDRG1 score was defined by an algorithm based on intensity of staining and percentage of stained nerve bundles. NDRG1 scores were correlated with paclitaxel induced neuropathy

Results

111 patients were studied. 17 of 111 (15%) developed severe paclitaxel-induced neuropathy. The mean nerve NDRG1 expression score was 5.4 in patients with severe neuropathy versus 7.7 in those without severe neuropathy (p = 0.0019). A Receiver operating characteristic (ROC) curve analysis of the mean nerve NDRG1 score revealed an area under the curve of 0.74 (p = 0.0013) for the identification of severe neuropathy, with a score of 7 being most discriminative. 13/54 (24%) subjects with an NDRG1 score < = 7 developed severe neuropathy, compared to only 4/57 (7%) in those with a score >7 (p = 0.017).

Conclusion

Low NDRG1 expression in nerve tissue present within samples of surgical resection may identify subjects at risk for severe paclitaxel-induced neuropathy. Since nerve biopsies are not routinely feasible for patients undergoing chemotherapy for early breast cancer, this promising biomarker strategy is compatible with current clinical workflow.

Safety and antitumor activity of selinexor (KPT-330), a first-in-class, oral XPO1 selective inhibitor of nuclear export: A phase I study expanded with colon cancer cohort

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Background: Tumor suppressor proteins (TSPs) are inactivated by their export from the nucleus by Exportin1 (XPO1/CRM1). The oral selective inhibitor of nuclear export selinexor (KPT-330)restores the nuclear localization and function of TSPs and shows a broad anti-tumor activity in animal models. Here we report on the treatment of a subset of patients (pts) with metastatic colorectal cancer (CRC) in a phase I trial of selinexor. Methods: Objectives were to determine the recommended phase 2 dose, evaluate safety, pharmacokinetics (PK), pharmacodynamics (PD), and tumor response (RECIST 1.1) of selinexor administered in two different schedules with 8 or 10 doses in a 28-day cycle. An expansion cohort of 15 pts with CRC was planned. Results: Twenty-seven pts with CRC were treated across eight doses (3-40 mg/m2) including 15 pts in the expansion cohort (30-35 mg/m2). Median age was 61 yrs and median number of prior regimens was 4. MTD of the 10-dose schedule was 30 mg/m2. MTD for the 8-dose schedule has not been reached. Thirteen pts experienced drug related gr 3-4 adverse events (AEs) including fatigue (n = 6), hyponatremia (n = 5), thrombocytopenia (n = 3), anorexia (n = 3), dehydration (n = 2), anemia (n = 2), hyperglycemia (n = 1), pulmonary embolism (n = 1), and hypotension (n = 1). The most common gr 1-2 drug related AEs were nausea (74 %), anorexia (67 %), fatigue (67 %), vomiting (59 %), dysgeusia (52 %), and weight loss (48 %). Cmax increased with dose to ≈ 1.4 µM with T½ of 4.0 – 7.4 hrs. Significant increases (2-20x) in PD marker XPO1 mRNA in circulating leukocytes were observed at all doses. Analysis of tumor biopsies confirmed nuclear localization of TSPs and induction of apoptosis following selinexor. CEA decreased in 4 of 12 pts. One pt had a partial response at 23 mg/m2, 6 patients had stable disease ≥8 weeks, and 3 patients had stable disease ≥24 weeks in 25 evaluable pts Conclusions: Preliminary signals of antitumor activity in CRC pts were observed. Selinexor is generally well tolerated and prolonged drug exposure is feasible. Selinexor induces Exportin in leucocytes and apoptosis in tumor biopsies with restoration of the nuclear location of TSPs. Clinical trial information: NCT01607905.

First-in-class, first-in-human phase I trial of KPT-330, a selective inhibitor of nuclear export (SINE) in patients (pts) with advanced solid tumors

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Background: In cancers, the majority of tumor suppressor proteins (TSP) are transported out of the nucleus exclusively by Exportin 1 (XPO1/CRM1), rendering these TSPs non-functional. KPT-330 is a potent inhibitor of XPO1, and forces the nuclear retention and activation of > 10 TSPs resulting in tumor cell death in vitro, in murine preclinical models and in dogs with spontaneous lymphomas. Methods: KPT-330 was administered orally for 10 doses in a 28-day cycle. Detailed pharmacokinetic (PK) and pharmacodynamic (PDn) analyses and serial tumor biopsies were performed. Response evaluation was done every 2 cycles (RECIST 1.1). All pts entering the study had documented progressive disease. Results: 23 pts (10 males; median age 62 yrs; ECOG PS 0/1: 5/18) received KPT-330 across 6 dose levels (3 to 30 mg/m2). There has been no dose limiting toxicity. Nine drug related grade 3/4 adverse events (AEs) post cycle 1 were reported in 6 pts (neutropenia, thrombocytopenia, hyponatremia, increased ALT, fatigue, vomiting [n=2], nausea [n=2]). The most common grade 1/2 AEs were nausea (78%), fatigue (74%) and anorexia (74%). PK analysis demonstrated a fairly proportional increase in Cmax and AUC with increasing dose, with no accumulation and without affecting half-life or clearance of KPT-330. At 30 mg/m2, AUC0-last. (4375 ng*h/mL) was comparable to the anti tumor exposure observed in mice and dogs. Tmax (~3 hrs) and T1/2 (6-7 hrs) were consistent across doses. Significant increase (2-20x) in XPO1 mRNA levels (PDn marker) in circulating leukocytes was observed at all doses, with higher doses demonstrating higher levels of XPO1 mRNA induction. Analysis of tumor biopsies confirmed nuclear localization of TSPs (e.g. p53, FOXO3A, IκB) and apoptosis of cancer cells following KPT-330 administration. RECIST response was evaluable in 13 pts. Stable disease (SD) was noted in 9 pts, with 3 (colon, endocervical & endometrial stromal tumors) remaining with SD at 6+ months (dose levels 3 & 6 mg/m2), as well as one minor response (colon). Conclusions: KPT-330 treatment is generally well tolerated, with favorable PK and PDn properties. Preliminary signals of clinical antitumor activity were observed. Clinical trial information: NCT01607905.

Phase I trial of trebananib (AMG 386) plus temsirolimus (Tr + T) in patients (pts) with advanced solid tumors (PJC-008/NCI#9041)

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Background: Preclinical data suggest that combined Ang1/2 and mTOR blockade has synergistic anti-cancer activity. The combination of Tr (inhibits angiogenesis by preventing interaction of Ang1/2 with Tie2) with the mTOR inhibitor T was evaluated in pts with advanced solid tumors to determine safety, tolerability, maximum tolerated dose (MTD), pharmacodynamics and preliminary antitumor activity. Methods: Pts were enrolled using 3+3 design. Tr and T were dosed on Day 1 (D1), 8, 15 and 22 of a 28-day cycle. Peripheral blood was collected for evaluation of Tie2-expressing monocytes (TEMs) and thymidine phosphorylase (TP) (an angiogenic enzyme increased in TEMs upon Tie2 stimulation) by flow cytometry. Tumor response was assessed every 2 cycles. Results: 13 pts have been enrolled, 6 at dose level (DL) 1 (15mg/kg Tr + 25mg T) and 7 (1 died from disease before DLT assessment) at DL -1 (15mg/kg Tr + 20mg T). Median age was 57yrs, ECOG 0-1, median previous chemotherapy lines 3 (range 1-8). In DL 1, 1/6 pts experienced DLT (Grade (Gr) 2 pneumonitis). In view of frequent Gr2 adverse events (AEs) in DL 1, DL -1 was evaluated with DLTs in 2/6 evaluable pts (Gr3 mucositis and intolerable Gr2 limb edema preventing start of cycle 2 within 14 days). The most common related AEs (all Gr across both DL) were: fatigue (77%), edema (69%), anorexia (62%), and nausea (54%). Common Gr≥3 AEs included lymphopenia (23%) and fatigue (23%). Of 10 evaluable pts, best RECIST responses were: 1 breast cancer pt (ER+/ HER2-/ PIK3CA mutant) with PR (now in cycle 9), 7 pts with SD, and 2 pts with PD. Four pts with ovarian cancer (1 PIK3CAmutant) had SD ≥11weeks with 2/3 pts (1 not evaluable) demonstrating GCIG response (>50% decrease in CA125). In preliminary analyses, TP expression in TEMs was decreased (mean -18%) in 4pts with tumor shrinkage, but increased (+6%) in 1pt with tumor growth, suggesting a trend between reduced TP and tumor response. Conclusions: The MTD was exceeded at 15mg/kg Tr and 20mg T weekly. The safety of 10mg/kg Tr and 20mg T weekly is currently being evaluated. The combination of Tr and T shows early signs of antitumor activity. TP expression in TEMs by flow cytometry as an early marker of treatment benefit warrants further evaluation. Clinical trial information: NCT01548482.

Phase I clinical trial of a genetically modified and oncolytic vaccinia virus GL-ONC1 with green fluorescent protein imaging (NCT009794131)

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Background: GL-ONC is a genetically engineered virus attenuated by insertion of the ruc-gfp (Renilla luciferase and Aequorea green fluorescent protein fusion gene), beta-galactosidase (lacZ) and beta-glucuronidase (gusA) reporter genes into the FL14.5L, J2R (thymidine kinase) and A56R (hemagglutinin) loci, respectively. A phase I trial of intravenous (i.v) GL-ONC1 was pursued to evaluate safety, tolerability, tumour delivery, neutralising antibody development and antitumor activity. Methods: GL-ONC1 was administered at escalating doses (1x105, 1x106, 1x107, 1x108, 1x109, 3x109 plaque forming units (pfu) on day 1; 1.667x107 and 1.667x108, 1.667x109pfu on days 1-3) utilizing a 28-day cycle and a 3+3 dose escalation design. Paired biopsies before treatment and on day 8 for pharmacodynamic and viral delivery evaluation were obtained. Green flourescent protein (GFP) imaging was performed on skin rash and mucosal tumour lesions at baseline and after each cycle. Results: To date, 33 patients (pts) across 8 cohorts have been treated with 1 dose limiting toxicty reported of grade 3 transaminitis after a single infusion at 1x109pfu. Other reported adverse events (n) included pyrexia (26), musculoskeletal pain (10), fatigue (8), nausea and vomiting (4). 2 pts had transient transaminitis; both had liver metastases, which may have contributed to this. 2 pts developed minimally symptomatic poxvirus skin pustules, which appeared green by GFP and were positive to viral plaque assay (VPA). Overall, stable disease (SD) by RECIST was seen at >24 weeks (n=6) and 8-12 weeks (n=5). 2 out of 4 pts in cohort 8 (one with cholangiocarcinoma and another with non-small cell lung caner) achieved SD for median 5.5 months, with a drop in tumour markers at the time of infusions. Conclusions: GL-ONC1 is well tolerated; more frequent delivery of the virus (2 weekly, at the same dose) is planned in an attempt to increase agent exposure. Clinical trial information: NCT009794131.

Genomic profile of a secretory breast cancer with an ETV6-NTRK3 duplication

BACKGROUND

Secretory breast cancer (SBC) is a rare entity characterised by indolent clinical behaviour, distinctive histological features and the presence of a recurrent chromosomal translocation t(12;15)(p13;q25), leading to the formation of the ETV6-NTRK3 fusion gene.

AIM

To describe the molecular genetic features of a case of SBC which harbours a duplication of the t(12;15) translocation.

METHODS

Tiling path array comparative genomic hybridisation (aCGH) analysis and fluorescence in situ hybridisation (FISH) using in-house-generated probes for ETV6, NTRK3 and the fusion genes, centromeric probes for chromosomes 12 and 15, and a commercially available split-apart ETV6/NTRK3 probe.

RESULTS

FISH revealed the presence of a duplication of the translocation t(12;15), which resulted from the gain of one copy of the derivative chromosome der(15)t(12;15), retention of one normal copy of both ETV6 and NTRK3 genes and deletion of the derivative chromosome der(12)t(12;15). Consistent with FISH findings, aCGH revealed copy number gains of ETV6 and NTRK3 and deletions encompassing the regions centromeric to ETV6 and telomeric to NTRK3. Additional regions of copy number changes included gains of 10q21, 10q26.3, 12p13.3-p13.31 15q11-q25.3 and 16pq and losses of 6q24.1-q27, 12p13.2-q12 and 15q25.3-q26.3.

CONCLUSIONS

To the best of our knowledge, this is the first time a carcinoma has been shown to harbour a duplication of the ETV6-NTRK3 translocation. The presence of an additional copy of the derivative chromosome der(15)t(12;15) coupled with deletion of the other derivative der(12)t(12;15) in the modal population of cancer cells suggests that this was either an early phenomenon or conferred additional growth advantage on neoplastic cells.

ESR1 amplification in endometrial carcinomas: hope or hyperbole?

The ESR1 gene maps 6q25 and encodes for oestrogen receptor alpha, which has been shown to play a pivotal role in the development of breast and endometrial cancer. It has recently been reported that oestrogen receptor alpha expression may be driven in some cases by ESR1 gene amplification and that this phenomenon may be an early event in breast and endometrial carcinogenesis. Although copy number gains of 6q have been reported by several groups, their prevalence, association with oestrogen receptor alpha expression, and clinical implications have been a matter of controversy. Here we discuss the key issues regarding the methods employed in the identification of ESR1 amplification, and briefly review the current literature and recent controversies on the subject of ESR1 amplification in endometrial and breast cancers.

Hereditary breast cancer: from molecular pathology to tailored therapies

Hereditary breast cancer accounts for up to 5-10% of all breast carcinomas. Recent studies have demonstrated that mutations in two high-penetrance genes, namely BRCA1 and BRCA2, are responsible for about 16% of the familial risk of breast cancer. Even though subsequent studies have failed to find another high-penetrance breast cancer susceptibility gene, several genes that confer a moderate to low risk of breast cancer development have been identified; moreover, hereditary breast cancer can be part of multiple cancer syndromes. In this review we will focus on the hereditary breast carcinomas caused by mutations in BRCA1, BRCA2, Fanconi anaemia (FANC) genes, CHK2 and ATM tumour suppressor genes. We describe the hallmark histological features of these carcinomas compared with non-hereditary breast cancers and show how an accurate histopathological diagnosis may help improve the identification of patients to be screened for mutations. Finally, novel therapeutic approaches to treat patients with BRCA1 and BRCA2 germ line mutations, including cross-linking agents and PARP inhibitors, are discussed.