Caloric restriction leads to druggable LSD1-dependent cancer stem cells expansion

Caloric Restriction (CR) has established anti-cancer effects, but its clinical relevance and molecular mechanism remain largely undefined. Here, we investigate CR's impact on several mouse models of Acute Myeloid Leukemias, including Acute Promyelocytic Leukemia, a subtype strongly affected by obesity. After an initial marked anti-tumor effect, lethal disease invariably re-emerges. Initially, CR leads to cell-cycle restriction, apoptosis, and inhibition of TOR and insulin/IGF1 signaling. The relapse, instead, is associated with the non-genetic selection of Leukemia Initiating Cells and the downregulation of double-stranded RNA (dsRNA) sensing and Interferon (IFN) signaling genes. The CR-induced adaptive phenotype is highly sensitive to pharmacological or genetic ablation of LSD1, a lysine demethylase regulating both stem cells and dsRNA/ IFN signaling. CR + LSD1 inhibition leads to the re-activation of dsRNA/IFN signaling, massive RNASEL-dependent apoptosis, and complete leukemia eradication in ~90% of mice. Importantly, CR-LSD1 interaction can be modeled in vivo and in vitro by combining LSD1 ablation with pharmacological inhibitors of insulin/IGF1 or dual PI3K/MEK blockade. Mechanistically, insulin/IGF1 inhibition sensitizes blasts to LSD1-induced death by inhibiting the anti-apoptotic factor CFLAR. CR and LSD1 inhibition also synergize in patient-derived AML and triple-negative breast cancer xenografts. Our data provide a rationale for epi-metabolic pharmacologic combinations across multiple tumors.

Quantifying geographical accessibility to cancer clinical trials in different income landscapes

Background

Clinical trials are increasingly perceived as a therapeutic opportunity for cancer patients. Favoring their concentration in few high-expertise academic centers maximizes quality of data collection but poses an issue of access equality. Analytical tools to quantify trial accessibility are needed to rationalize resources.

Materials and methods

We constructed a distance-based accessibility index (dAI) using publicly available data on demographics, cancer incidence and trials. Multiple strategies were applied to mitigate or quantify clear sources of bias: reporting biases by text mining multiple registries; reliability of simple geographical distance by comparison with high-quality travel cost data for Italy; index inflation due to highly heterogeneous cancer incidence by log-transformation. We studied inequalities by Gini index and time trend significance by Mann–Kendall test. We simulated different resource allocation models in representative countries and identified locations where new studies would maximally improve the national index.

Results

The dAI approximated well a more realistic but not widely applicable travel cost-based index. Accessibility was unevenly distributed across and within countries (Gini index ∼0.75), with maximal inequalities in high- and upper-middle-income countries (China, United States, Russian Federation). Over time, accessibility increased but less than the total number of trials, most evidently in upper-middle-income countries. Simulations in representative countries (Italy and Serbia) identified ideal locations able to maximally raise the national index.

Conclusions

Access to clinical trials is highly uneven across and within countries and is not mitigated by simple increase in the number of trials; a rational algorithmic approach can be used to mitigate inequalities.

•

Accessibility to cancer clinical trials grew less than total number of trials over time in upper-middle-income countries.

•

Accessibility is unevenly distributed, with maximal inequalities in high- and upper-middle-income countries.

•

Simulation of resource allocation can identify ideal locations able to raise the national accessibility index.

Abstract CT167: Neoadjuvant ipilimumab/nivolumab in locally advanced or oligometastatic melanoma: An open label, single arm, multi-institutional clinical study with molecular and immunological biomarker’s analysis

Efficacy, safety, together with molecular and immunological biomarkers were studied in a sequential clinical trial of neoadjuvant immunotherapy, surgery and adjuvant immunotherapy in locally advanced or oligometastatic melanoma patients (pts), within an open label, single arm and two sites study. Treatment schedule consisted in four primary cycles of inverted dose ipilimumab 1 mg/kg and nivolumab 3 mg/kg every 3 weeks, followed by radical surgery and adjuvant nivolumab 480 mg every 4 weeks for 6 cycles. Primary objective was pathological complete remission (pCR) rate, according to International Neoadjuvant Melanoma Consortium (INMC) criteria, while secondary objectives were: safety, feasibility and efficacy; QoL; identification of biomarkers of response and resistance; degree of immune activation; longitudinal evaluation of the gut microbiome. From March 2019 to April 2021, 43 pts were enrolled in the trial and, with an intent to treat of 35 pts, 34 completed the primary phase, 31 received surgery and 28 completed the adjuvant phase. Four pts were withdrawn during primary phase for progression (2), toxicity (1) and consent withdrawal (1). Study primary endpoint has been met since 20/31 pts undergoing surgery reached a pCR/near pCR (65%), 4/31 (13%) a pathological partial remission (pPR) and 7/31 (22%) pts a pathological no response. With a median follow-up of 17 months, 33/35 pts are alive. Treatment failure occurred in 9 pts: 2 pts progressed during primary phase and did not undergo surgery; 7 pts progressed during adjuvant (3 pts) or follow-up phase (4 pts). Six out of these 7 pts were classified as pNR at surgery, while the other, classified as pCR, did not receive adjuvant therapy. Both pts in stage IV relapsed. Unfortunately, one pt died for ischemic stroke after 5 months from adjuvant therapy while on CR. Treatment related toxicities were mainly G1-2 and only 6 pts (17%) developed G3-4 adverse events (AE): 3 transaminitis, 1 pneumonitis, 1 myocarditis, 1 CPK increase and 1 dermatomyositis. Translational studies on samples collected before, during therapy and at progression have been performed: whole exome sequencing and gut microbiota dynamics on longitudinal samples showed some relationships with responses and developing resistances. These data, never presented elsewhere previously, are in part new and in part confirmatory of immunological or molecular signatures described by other groups. In conclusion, primary immunotherapy with Ipilimumab/Nivolumab in pts affected by locally advanced/oligometastatic melanoma is able to achieve an elevated pCR/near pCR rate which appears to be predictive of long term relapse free survival. Translational data analyzed longitudinally on each patient can allow for a better selection of pts, giving new insight on the mechanisms of melanoma progression and resistance.

Citation Format: Pier Francesco Ferrucci, Bruno Achutti Duso, Luigi Nezi, Luca Mazzarella, Fiorenza Lotti, Sara Gandini, Gianmarco Orsolini, Elisabetta Pennacchioli, Patrizia Gnagnarella, Teresa Manzo, Simone Ribero, Maria Teresa Fierro, Rebecca Senetta, Concetta Riviello, Virginia Caliendo, Pietro Quaglino, Massino Barberis, Giuseppina Bonizzi, Emilia Cocorocchio. Neoadjuvant ipilimumab/nivolumab in locally advanced or oligometastatic melanoma: An open label, single arm, multi-institutional clinical study with molecular and immunological biomarker’s analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT167.

Abstract 1164: Somatic NF1 loss in breast cancer leads to centrosome amplification, aneuploidy and increased sensitivity to T-DM1

Background: Centrosome amplification (CA, the presence of >2 centrosomes) is a hallmark of several tumors. CA perturbs mitosis by generating nonphysiological pulling forces, leading to chromosome missegregation and aneuploidy. This condition may be advantageous for tumor outgrowth providing it gets corrected by clustering centrosomes into a pseudo-bipolar conformation for successful cell division. Molecular determinants of CA and therapeutic opportunities in breast cancer (BC) are still poorly understood. Preliminary data from our group show that somatic NF1 loss of function (LOF), common upon metastatic progression, is associated in vitro and in patients with selective sensitivity to maytansinoids such as T-DM1. Here, we explored the molecular basis of this increased sensitivity.

Methods: Multiple CRISPR/Cas9-generated NF1KO or WT clones of HER2+ BC cell lines (BT474, SKBR3 and HCC1954) were assessed for sensitivity to T-DM1 or DM1 in BrdU-based and clonogenic assays, with RNAseq being performed. BT474 cells were furthered engineered with the FUCCI(Ca) reporter for live cell cycle imaging. Ploidy was assessed through flow cytometry. Aneuploidy in the GENIE cohort (restricted to BC patients analyzed with NF1-covering panels) was assessed by generating a segmentation score (sum of the absolute ploidy scores in segments covered by NGS panels). Centrosomes, spindle conformation and chromosome abnormalities were studied by confocal microscopy in cells synchronized both with RO3306 or thymidine block.

Results: All lines showed increased sensitivity to T-DM1 in KO vs WT in BrdU-based and clonogenic assays; similar results were obtained with DM1 only, suggesting independence from HER2 targeting. RNAseq differential analysis showed significant enrichment for gene sets involved in mitotic spindle in KO but not WT cells upon T-DM1 treatment. FUCCI analysis showed significantly longer permanence in G2/M in NF1KO compared to WT cells (24.8 vs 17.9% in G2/M, p=1.81E-07). In vehicle-treated synchronized cells, significantly more KO cells showed >2 centrosomes (21.6 vs 4.7%, p<0.00001) and multiple pseudo-bipolar mitotic figures with narrow intercentriolar distances, indicative of efficient clustering. This was associated with more frequent chromosome misalignment (26.7 vs 6.7%, p=0.038). In the GENIE cohort, segmentation score was higher for patients with NF1 LOF mutations vs NF1 WT (median 46.7 vs 41.1, p=0.0023), indicative of more common aneuploidy. Upon T-DM1, KO cells exhibited significantly more non-bipolar spindles with massively wider intercentriolar distances.

Conclusions: Somatic NF1 loss causes aneuploidy due to CA. This likely favors metastatization and can be exploited therapeutically. CA associated with other common oncogenic events (RAS and BRCA1/2 mutations, PTEN loss) may represent a general biomarker for drugs inhibiting centrosome clustering in BC.

Citation Format: Bruno Achutti Duso, Elena Gavilan Dorronzoro, Giulia Tini, Maria de Filippo, Marica Ippolito, Chiara Soriani, Simona Rodighiero, Stefano Santaguida, Pier Giuseppe Pelicci, Luca Mazzarella. Somatic NF1 loss in breast cancer leads to centrosome amplification, aneuploidy and increased sensitivity to T-DM1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1164.

Combining immunotherapy with an epidrug in squamous cell carcinomas of different locations: rationale and design of the PEVO basket trial

Squamous cell carcinomas (SCCs) are among the most frequent solid tumors in humans. SCCs, related or not to the human papillomavirus, share common molecular features. Immunotherapies, and specifically immune checkpoint inhibitors, have been shown to improve overall survival in multiple cancer types, including SCCs. However, only a minority of patients experience a durable response with immunotherapy. Epigenetic modulation plays a major role in escaping tumor immunosurveillance and confers resistance to immune checkpoint inhibitors. Preclinical evidence suggests that modulating the epigenome might improve the efficacy of immunotherapy. We herein review the preclinical and the clinical rationale for combining immunotherapy with an epidrug, and detail the design of PEVOsq, a basket clinical trial combining pembrolizumab with vorinostat, a histone deacetylase inhibitor, in patients with SCCs of different locations. Sequential blood and tumor sampling will be collected in order to identify predictive and pharmacodynamics biomarkers of efficacy of the combination. We also present how clinical and biological data will be managed with the aim to enable the development of a prospective integrative platform to allow secure and controlled access to the project data as well as further exploitations.

Circulating tumour DNA and melanoma survival: A systematic literature review and meta-analysis

We reviewed and meta-analysed the available evidence (until December 2019) about circulating tumour DNA (ctDNA) levels and melanoma patients survival. We included twenty-six studies (>2000 patients overall), which included mostly stage III-IV cutaneous melanoma patients and differed widely in terms of systemic therapy received and somatic mutations that were searched. Patients with detectable ctDNA before treatment had worse progression-free survival (PFS) (summary hazard ratio (SHR) 2.47, 95 % confidence intervals (CI) 1.85-3.29) and overall survival (OS) (SHR 2.98, 95 % CI 2.26-3.92), with no difference by tumour stage. ctDNA detectability during follow-up was associated with poorer PFS (SHR 4.27, 95 %CI 2.75-6.63) and OS (SHR 3.91, 95 %CI 1.97-7.78); in the latter case, the association was stronger (p = 0.01) for stage IV vs. III melanomas. Between-estimates heterogeneity was low for all pooled estimates. ctDNA is a strong prognostic biomarker for advanced-stage melanoma patients, robust across tumour (e.g. genomic profile) and patients (e.g. systemic therapy) characteristics.

Semantic and Geographical Analysis of COVID-19 Trials Reveals a Fragmented Clinical Research Landscape Likely to Impair Informativeness

Background: The unprecedented impact of the COVID-19 pandemic on modern society has ignited a "gold rush" for effective treatment and diagnostic strategies, with a significant diversion of economic, scientific, and human resources toward dedicated clinical research. We aimed to describe trends in this rapidly changing landscape to inform adequate resource allocation. Methods: We developed an online repository (COVID Trial Monitor) to analyze in real time the growth rate, geographical distribution, and characteristics of COVID-19 related trials. We defined structured semantic ontologies with controlled vocabularies to categorize trial interventions, study endpoints, and study designs. Analyses are publicly available at https://bioinfo.ieo.it/shiny/app/CovidCT. Results: We observe a clear prevalence of monocentric trials with highly heterogeneous endpoints and a significant disconnect between geographic distribution and disease prevalence, implying that most countries would need to recruit unrealistic percentages of their total prevalent cases to fulfill enrolment. Conclusions: This geographically and methodologically incoherent growth casts doubts on the actual feasibility of locally reaching target sample sizes and the probability of most of these trials providing reliable and transferable results. We call for the harmonization of clinical trial design criteria for COVID-19 and the increased use of larger master protocols incorporating elements of adaptive designs. COVID Trial Monitor identifies critical issues in current COVID-19-related clinical research and represents a useful resource with which researchers and policymakers can improve the quality and efficiency of related trials.

Opportunities and challenges of implementing Pharmacogenomics in cancer drug development

Cancer drug development is a time and resources consuming process. Around 90% of drugs entering clinical trials fail due to lack of efficacy and/or safety issues, more often after conspicuous research and economic efforts. Part of the discarded drugs might be beneficial only in a subgroup of the study patients, and some adverse events might be prevented by identifying those patients more vulnerable to toxicities. The implementation of pharmacogenomic biomarkers allows the categorization of patients, to predict efficacy and toxicity and to optimize the drug development process. Around seventy FDA approved drugs currently present one or more genetic biomarker to keep in consideration, and with the progress of Precision Medicine tailoring therapies on individuals' genomic landscape promises to become a new standard of cancer care. In the current article we review the role of pharmacogenomics in cancer drug development, underlying the advantages and challenges of their implementation.

Homologous recombination deficiency in triple negative breast cancer

Triple negative breast cancer (TNBC) represents a heterogeneous subtype of breast cancer characterized by an unfavorable prognosis due to its aggressive biology. The median overall survival (OS) for patients with metastatic TNBC is around 9-12 months with conventional cytotoxic agents. Considering this suboptimal outcome, which is induced despite of medical treatment, new therapeutic strategies would be urgently needed. The ultimate goal of precision medicine is to identify specific molecular alterations that permit considering effective targeted drug(s). Germline BRCA mutations occur in 10-20% of TNBC patients while somatic mutations occur in 3-5% of them. Alterations in the homologous recombination (HR) system are typical of BRCA mutant tumors, but can also be identified in tumors that do not carry this mutation, defining a subgroup of patients referred to as BRCAness. In this review, we focus on the role of homologous recombination deficiency (HRD) as both predictive and prognostic factor in different settings of TNBC patients treated with DNA damaging drugs and poly ADP ribose polymerase (PARP) inhibitors.

Liver toxicity in the era of immune checkpoint inhibitors: A practical approach

Immune checkpoint inhibitors have revolutionized the cancer treatment with an approved efficacy in different solid tumors and hematologic malignancies. These agents are increasing the indication in cancer treatment, but can be associated with serious immune-related adverse effects (IRAEs). Dermatologic and gastrointestinal toxicities are the most common IRAE followed by endocrinopathies with a different time of occurrence. Rarely cases of gastrointestinal toxicities are observed almost 2 years after initiation of the therapy. In this review we focus on liver toxicity related to these immunotherapeutic agents for which the largest amount of safety data is available. The management of drug-induced liver toxicity is very complicated and in same cases may take a long period of time to be resolved. A prompt recognition of liver IRAEs and an appropriate management of this event, requiring close collaboration with other specialist figures, could improve its treatment with evident implication on the efficacy of the therapy.

Targeting the microenvironment in solid tumors

Tumorigenesis is a complex and dynamic process involving different cellular and non-cellular elements composed of tumor microenvironment (TME). The interaction of TME with cancer cells is responsible for tumor development, progression and drug resistance. TME consists of non malignant cells of the tumor such as cancer associated fibroblasts (CAFs), endothelial cells and pericytes composing tumor vasculature, immune and inflammatory cells, bone marrow derived cells, and the extracellular matrix (ECM) establishing a complex cross-talk with tumor. These interactions contribute towards proliferation and invasion of the tumor by producing growth factors, chemokines and matrix-degrading enzymes. ECM is a complex system containing macromolecules with distinctive physical, biochemical and biomechanical properties. During tumorigenesis this system is deregulated favoring the generation of tumorigenic microenvironment enhancing tumor-associated angiogenesis and inflammation. An important step of anticancer treatment is the identification of the biological alterations present in TME in order to target these key molecular players. Multitargeted approaches, providing a simultaneous inhibition of TME components, may offer a more efficient way to treat cancer. In this manuscript we overview the function of each components of TME and the treatments targeting the key players.

Clinical efficacy of ribociclib as a first-line therapy for HR-positive, advanced breast cancer

INTRODUCTION

Breast cancer (BC) remains the most frequently diagnosed cancer and the most common cause of cancer death among women of all races worldwide. Over 80% of BC cases are hormone receptor (HR)-positive, comprised of luminal A and luminal B per molecular subtypes, imposing an urgent need to fully understand the mechanisms behind progression. Ribociclib is a selective cycline-dependent kinase 4 and 6 inhibitor. A phase 1 and a phase 3 trial have established a definitive role of ribociclib as frontline in the treatment of endocrine-sensitive advanced BC. Areas covered: Herein, the authors provide an overview of the data on ribociclib covering all aspects of the drug from its pharmacokinetics to efficacy and safety. The authors also provide their perspectives for the future. Expert opinion: Ribociclib is offering an opportunity to explore a new compound at the crossroads of different molecular activity and cell targets, which focus on endocrine-resistance reversal in multiple settings including early BC. Moreover, its activity against different subtypes of BC is being studied as is its immune-modulating effect. One cautionary note is that, in a market of concomitant similar competitors, a financial discussion will be mandatory.

Mortality of Adult Critically Ill Subjects With Cancer

BACKGROUND

Cancer patients may require intensive care support for postoperative care, complications associated with underlying malignancy, or toxicities related to cancer therapy. The higher mortality rates found in this population than in the population of ICU patients without cancer may be attributable to confounding due to a higher prevalence of multiple organic dysfunctions at ICU admission in patients with malignancy; however, data regarding this hypothesis are scarce. Accordingly, we performed the present study to compare the crude and propensity score-matched mortality rates between adult subjects with and without cancer admitted to a mixed medical-surgical ICU.

METHODS

We conducted a retrospective analysis of a comprehensive longitudinal ICU database in a tertiary referral hospital in Southern Brazil. All adult subjects who were admitted to the ICU from January 2008 to December 2014 were evaluated. Crude and propensity score-matched all-cause 30-d mortality rates of critically ill subjects with cancer were compared with those of critically ill subjects without cancer.

RESULTS

A total of 4,221 subjects were evaluated. The survival analysis revealed that the crude mortality rate was higher among subjects with cancer than among subjects without cancer (18.7% vs 10.2%, P < .001). However, after matching by propensity score, the 30-d mortality rates of subjects with and without cancer were similar (18.5% vs 15.2%, P = .17).

CONCLUSIONS

The present study failed to show an association between malignancy and all-cause 30-d mortality rate in adult subjects admitted to a mixed medical-surgical ICU. The propensity score-matched analysis showed no evidence of excessive mortality due to cancer diagnosis.