bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from First-in-Human Study of AT13148, a Dual ROCK-AKT Inhibitor in Patients with Solid Tumors
Authors: McLeod Robert , Kumar Rajiv , Papadatos-Pastos Dionysis , Mateo Joaquin , Brown Jessica S. , Garces Alvaro H. Ingles , Ruddle Ruth , Decordova Shaun , Jueliger Simone , Ferraldeschi Roberta , Maiques Oscar , Sanz-Moreno Victoria , Jones Paul , Traub Stephanie , Halbert Gavin , Mellor Sarah , Swales Karen E. , Raynaud Florence I. , Garrett Michelle D. , Banerji Udai
Published: April 2023

AbstractPurpose:
AT13148 is an oral AGC kinase inhibitor, which potently inhibits ROCK and AKT kinases. In preclinical models, AT13148 has been shown to have antimetastatic and antiproliferative activity.
Patients and Methods:
The trial followed a rolling six design during dose escalation. An intrapatient dose escalation arm to evaluate tolerability and a biopsy cohort to study pharmacodynamic effects were later added. AT13148 was administered orally three days a week (Mon–Wed–Fri) in 28-day cycles. Pharmacokinetic profiles were assessed using mass spectrometry and pharmacodynamic studies included quantifying p-GSK3β levels in platelet-rich plasma (PRP) and p-cofilin and p-MLC2 levels in tumor biopsies.
Results:
Fifty-one patients were treated on study. The safety of 5–300 mg of AT13148 was studied. Further, the doses of 120–180–240 mg were studied in an intrapatient dose escalation cohort. The dose-limiting toxicities included hypotension (300 mg), pneumonitis, and elevated liver enzymes (240 mg), and skin rash (180 mg). The most common side effects were fatigue, nausea, headaches, and hypotension. On the basis of tolerability, 180 mg was considered the maximally tolerated dose. At 180 mg, mean Cmax and AUC were 400 nmol/L and 13,000 nmol/L/hour, respectively. At 180 mg, ≥50% reduction of p-cofilin was observed in 3 of 8 posttreatment biopsies.
Conclusions:
AT13148 was the first dual potent ROCK-AKT inhibitor to be investigated for the treatment of solid tumors. The narrow therapeutic index and the pharmacokinetic profile led to recommend not developing this compound further. There are significant lessons learned in designing and testing agents that simultaneously inhibit multiple kinases including AGC kinases in cancer.
Data from Arginine Starvation and Docetaxel Induce c-Myc–Driven hENT1 Surface Expression to Overcome Gemcitabine Resistance in ASS1-Negative Tumors
Authors: Prudner Bethany C. , Rathore Richa , Robinson Anthony M. , Godec Abigail , Chang Samuel F. , Hawkins William G. , Hirbe Angela C. , Van Tine Brian A.
Published: April 2023

AbstractPurpose:
The response to acute and long-term arginine starvation results in a conditional adaptive metabolic reprogramming that can be harnessed for therapeutic opportunities in ASS1-negative tumors. Here, we investigate the underlying biology of priming ASS1− tumors with arginine deiminase (ADI-PEG20) before treatment with gemcitabine (GEM) and docetaxel (DTX) in sarcoma, pancreatic cancer, and melanoma cell lines.
Experimental Design:
ASS1− tumor cell lines were treated to create LTAT (long-term ADI treated) cell lines (ASS1+) and used for drug combination studies. Protein expression of ASS1, dCK, RRM2, E2F1, c-MYC, and hENT1 was measured. c-MYC activity was determined, live-cell immunofluorescent studies for hENT1, uptake assays of FITC-cytosine probe, and rescue studies with a c-MYC inhibitor were all determined in the presence or absence of the ADI-PEG20:GEM:DTX.
Results:
In examining modulations within the pyrimidine pathway, we identified that the addition of DTX to cells treated with ADI-PEG20 resulted in translocation of stabilized c-Myc to the nucleus. This resulted in an increase of hENT1 cell-surface expression and rendered the cells susceptible to GEM. In vivo studies demonstrate that the combination of ADI-PEG20:GEM:DTX was optimal for tumor growth inhibition, providing the preclinical mechanism and justification for the ongoing clinical trial of ADI-PEG20, GEM, and DTX in sarcoma.
Conclusions:
The priming of tumors with ADI-PEG20 and DTX results in the stabilization of c-MYC potentiating the effect of GEM treatment via an increase in hENT1 expression. This finding is applicable to ASS1-deficient cancers that are currently treated with GEM.
Data from Circulating Tumor DNA Sequencing Analysis of Gastroesophageal Adenocarcinoma
Authors: Maron Steven B. , Chase Leah M. , Lomnicki Samantha , Kochanny Sara , Moore Kelly L. , Joshi Smita S. , Landron Stacie , Johnson Julie , Kiedrowski Lesli A. , Nagy Rebecca J. , Lanman Richard B. , Kim Seung Tae , Lee Jeeyun , Catenacci Daniel V.T.
Published: April 2023

AbstractPurpose:
Gastroesophageal adenocarcinoma (GEA) has a poor prognosis and few therapeutic options. Utilizing a 73-gene plasma-based next-generation sequencing (NGS) cell-free circulating tumor DNA (ctDNA-NGS) test, we sought to evaluate the role of ctDNA-NGS in guiding clinical decision-making in GEA.
Experimental Design:
We evaluated a large cohort (n = 2,140 tests; 1,630 patients) of ctDNA-NGS results (including 369 clinically annotated patients). Patients were assessed for genomic alteration (GA) distribution and correlation with clinicopathologic characteristics and outcomes.
Results:
Treatment history, tumor site, and disease burden dictated tumor-DNA shedding and consequent ctDNA-NGS maximum somatic variant allele frequency. Patients with locally advanced disease having detectable ctDNA postoperatively experienced inferior median disease-free survival (P = 0.03). The genomic landscape was similar but not identical to tissue-NGS, reflecting temporospatial molecular heterogeneity, with some targetable GAs identified at higher frequency via ctDNA-NGS compared with previous primary tumor-NGS cohorts. Patients with known microsatellite instability-high (MSI-High) tumors were robustly detected with ctDNA-NGS. Predictive biomarker assessment was optimized by incorporating tissue-NGS and ctDNA-NGS assessment in a complementary manner. HER2 inhibition demonstrated a profound survival benefit in HER2-amplified patients by ctDNA-NGS and/or tissue-NGS (median overall survival, 26.3 vs. 7.4 months; P = 0.002), as did EGFR inhibition in EGFR-amplified patients (median overall survival, 21.1 vs. 14.4 months; P = 0.01).
Conclusions:
ctDNA-NGS characterized GEA molecular heterogeneity and rendered important prognostic and predictive information, complementary to tissue-NGS.

See related commentary by Frankell and Smyth, p. 6893
Data from Glioblastoma-mediated Immune Dysfunction Limits CMV-specific T Cells and Therapeutic Responses: Results from a Phase I/II Trial
Authors: Weathers Shiao-Pei , Penas-Prado Marta , Pei Be-Lian , Ling Xiaoyang , Kassab Cynthia , Banerjee Pinaki , Bdiwi Mustafa , Shaim Hila , Alsuliman Abdullah , Shanley Mayra , de Groot John F. , O'Brien Barbara J. , Harrison Rebecca , Majd Nazanin , Kamiya-Matsuoka Carlos , Fuller Gregory N. , Huse Jason T. , Chi Linda , Rao Ganesh , Weinberg Jeffrey S. , Lang Frederick F. , Sawaya Raymond , Shpall Elizabeth J. , Rezvani Katayoun , Heimberger Amy B.
Published: April 2023

AbstractPurpose:
Cytomegalovirus (CMV) antigens occur in glioblastoma but not in normal brains, making them desirable immunologic targets.
Patients and Methods:
Highly functional autologous polyclonal CMV pp65-specific T cells from patients with glioblastoma were numerically expanded under good manufacturing practice compliant conditions and administered after 3 weeks of lymphodepleting dose-dense temozolomide (100 mg/m2) treatment. The phase I component used a 3+3 design, ascending through four dose levels (5 × 106–1 × 108 cells). Treatment occurred every 6 weeks for four cycles. In vivo persistence and effector function of CMV-specific T cells was determined by dextramer staining and multiparameter flow cytometry in serially sampled peripheral blood and in the tumor microenvironment.
Results:
We screened 65 patients; 41 were seropositive for CMV; 25 underwent leukapheresis; and 20 completed ≥1 cycle. No dose-limiting toxicities were observed. Radiographic response was complete in 1 patient, partial in 2. Median progression-free survival (PFS) time was 1.3 months [95% confidence interval (CI), 0–8.3 months]; 6-month PFS was 19% (95% CI, 7%–52%); and median overall survival time was 12 months (95% CI, 6 months to not reached). Repeated infusions of CMV-T cells paralleled significant increases in circulating CMV+ CD8+ T cells, but cytokine production showing effector activity was suppressed, especially from T cells obtained directly from glioblastomas.
Conclusions:
Adoptive infusion of CMV-specific T cells after lymphodepletion with dose-dense temozolomide was well tolerated. But apparently CMV seropositivity does not guarantee tumor susceptibility to CMV-specific T cells, suggesting heterogeneity in CMV antigen expression. Moreover, effector function of these T cells was attenuated, indicating a requirement for further T-cell modulation to prevent their dysfunction before conducting large-scale clinical studies.
Data from Comprehensive Genomic Analysis of Translocation Renal Cell Carcinoma Reveals Copy-Number Variations as Drivers of Disease Progression
Authors: Marcon Julian , DiNatale Renzo G. , Sanchez Alejandro , Kotecha Ritesh R. , Gupta Sounak , Kuo Fengshen , Makarov Vladimir , Sandhu Amar , Mano Roy , Silagy Andrew W. , Blum Kyle A. , Nassau Daniel E. , Benfante Nicole E. , Ortiz Michael V. , Carlo Maria I. , Chan Timothy A. , Motzer Robert J. , Voss Martin H. , Coleman Jonathan , Russo Paul , Reuter Victor , Hakimi A. Ari , Reznik Ed
Published: April 2023

AbstractPurpose:
Translocation renal cell carcinoma (tRCC) is a rare, aggressive renal cell carcinoma (RCC) subtype. There is currently limited understanding on the role of molecular alterations in the pathogenesis and progression of these tumors. We investigated the association between somatic alterations and clinical outcomes in two independent cohorts profiled using DNA sequencing.
Experimental Design:
Twenty-two tRCCs underwent targeted sequencing [Memorial Sloan Kettering Cancer Center (MSK)-IMPACT]; a subset was profiled using exome-sequencing and combined with exome data from The Cancer Genome Atlas (TCGA) for analysis. The prognostic value of specific somatic aberrations, tumor mutation burden (TMB), and fraction of copy-number–altered genome (FCNAg) was explored. In TCGA cases, neoantigen prediction and immune cell deconvolution were performed using RNA-sequencing and exome data. Overall survival estimates were computed using the Kaplan–Meier method; time-on-treatment was calculated for 14 MSK-IMPACT patients who underwent systemic therapy. Associations between molecular features and outcomes were evaluated using nonparametric testing.
Results:
Copy-number aberrant tRCCs were associated with poor overall survival (P = 0.03). Pediatric patients had tumors with lower FCNAg (P = 0.01). In one adult case with two chronologically distinct tumor samples sequenced, we confirmed that copy-number events occurred early during evolution. TERT promoter mutations were found exclusively in high-stage tumors. We found that tRCCs displayed distinct angiogenesis and PD-L1 gene expression profiles compared with other RCC subtypes.
Conclusions:
Tumors molecularly defined by increased copy-number variations were associated with aggressive disease in tRCC. A higher burden of genomic events in adults compared with pediatric cases likely reflects a more aggressive clinical course. The unique immunophenotypic characteristics of tRCC merit further exploration.
Data from Identification of Somatically Acquired BRCA1/2 Mutations by cfDNA Analysis in Patients with Metastatic Breast Cancer
Authors: Vidula Neelima , Dubash Taronish , Lawrence Michael S. , Simoneau Antoine , Niemierko Andrzej , Blouch Erica , Nagy Becky , Roh Whijae , Chirn Brian , Reeves Brittany A. , Malvarosa Giuliana , Lennerz Jochen , Isakoff Steven J. , Juric Dejan , Micalizzi Douglas , Wander Seth , Spring Laura , Moy Beverly , Shannon Kristen , Younger Jerry , Lanman Richard , Toner Mehmet , Iafrate A. John , Getz Gad , Zou Lee , Ellisen Leif W. , Maheswaran Shyamala , Haber Daniel A. , Bardia Aditya
Published: April 2023

AbstractPurpose:
Plasma genotyping may identify mutations in potentially “actionable” cancer genes, such as BRCA1/2, but their clinical significance is not well-defined. We evaluated the characteristics of somatically acquired BRCA1/2 mutations in patients with metastatic breast cancer (MBC).
Experimental Design:
Patients with MBC undergoing routine cell-free DNA (cfDNA) next-generation sequencing (73-gene panel) before starting a new therapy were included. Somatic BRCA1/2 mutations were classified as known germline pathogenic mutations or novel variants, and linked to clinicopathologic characteristics. The effect of the PARP inhibitor, olaparib, was assessed in vitro, using cultured circulating tumor cells (CTCs) from a patient with a somatically acquired BRCA1 mutation and a second patient with an acquired BRCA2 mutation.
Results:
Among 215 patients with MBC, 29 (13.5%) had somatic cfDNA BRCA1/2 mutations [nine (4%) known germline pathogenic and rest (9%) novel variants]. Known germline pathogenic BRCA1/2 mutations were common in younger patients (P = 0.008), those with triple-negative disease (P = 0.022), and they were more likely to be protein-truncating alterations and be associated with TP53 mutations. Functional analysis of a CTC culture harboring a somatic BRCA1 mutation demonstrated high sensitivity to PARP inhibition, while another CTC culture harboring a somatic BRCA2 mutation showed no differential sensitivity. Across the entire cohort, APOBEC mutational signatures (COSMIC Signatures 2 and 13) and the “BRCA” mutational signature (COSMIC Signature 3) were present in BRCA1/2-mutant and wild-type cases, demonstrating the high mutational burden associated with advanced MBC.
Conclusions:
Somatic BRCA1/2 mutations are readily detectable in MBC by cfDNA analysis, and may be present as both known germline pathogenic and novel variants.
Data from Enhancing Abiraterone Acetate Efficacy in Androgen Receptor–positive Triple-negative Breast Cancer: Chk1 as a Potential Target
Authors: Grellety Thomas , Callens Celine , Richard Elodie , Briaux Adrien , Vélasco Valérie , Pulido Marina , Gonçalves Anthony , Gestraud Pierre , MacGrogan Gaetan , Bonnefoi Hervé , Cardinaud Bruno
Published: April 2023

AbstractPurpose:
Our aim was to identify predictive factors of abiraterone acetate efficacy and putative new druggable targets in androgen receptor (AR)-positive triple-negative breast cancer (TNBC) treated in the UCBG 2012-1 trial.

Experimental Design: We defined abiraterone acetate response as either complete or partial response, or stable disease at 6 months. We sequenced 91 general and breast cancer–associated genes from the tumor DNA samples. We analyzed transcriptomes from the extracted RNA samples on a NanoString platform and performed IHC using tissue microarrays. We assessed abiraterone acetate and Chk1 inhibitors (GDC-0575 and AZD7762) efficacies, either alone or in combination, on cell lines grown in vitro and in vivo.
Results:
Classic IHC apocrine markers including AR, FOXA1, GGT1, and GCDFP15, from patients' tumors allowed identifying abiraterone acetate-responders and nonresponders. All responders had clear apocrine features. Transcriptome analysis revealed that 31 genes were differentially expressed in the two subgroups, 9 of them being linked to proliferation and DNA damage repair. One of the most significant differences was the overexpression, in nonresponders, of CHEK1, a gene encoding Chk1, a protein kinase that can be blocked by specific inhibitors. On the basis of cell line experiments, abiraterone acetate and Chk1 inhibitor combination showed at least additive effect on cell viability, cell cycle, apoptosis, and accumulation of DNA damages. In vivo, orthotopic xenograft experiments confirmed the efficacy of this combination therapy.
Conclusions:
This study suggests that apocrine features can be helpful in the identification of abiraterone acetate-responders. We identified Chk1 as a putative drug target in AR-positive TNBCs.
Data from A Phase II Study of Tumor-infiltrating Lymphocyte Therapy for Human Papillomavirus–associated Epithelial Cancers
Authors: Stevanović Sanja , Helman Sarah R. , Wunderlich John R. , Langhan Michelle M. , Doran Stacey L. , Kwong Mei Li M. , Somerville Robert P.T. , Klebanoff Christopher A. , Kammula Udai S. , Sherry Richard M. , Yang James C. , Rosenberg Steven A. , Hinrichs Christian S.
Published: April 2023

AbstractPurpose:
Cellular therapy is an emerging cancer treatment modality, but its application to epithelial cancers has been limited. This clinical trial evaluated tumor-infiltrating lymphocyte (TIL) therapy for the treatment of patients with metastatic human papillomavirus (HPV)-associated carcinomas.
Patients and Methods:
The trial was a phase II design with two cohorts, cervical cancers and noncervical cancers. Cell infusion was preceded by a lymphocyte-depleting conditioning regimen and followed by systemic high-dose aldesleukin.
Results:
Objective tumor responses occurred in 5 of 18 (28%) patients in the cervical cancer cohort and 2 of 11 (18%) patients in the noncervical cancer cohort. Two of the responses in cervical cancer were complete and are ongoing 67 and 53 months after treatment. Responses in the noncervical cancer cohort were in anal cancer and oropharyngeal cancer. The HPV reactivity of the infused T cells correlated with clinical response. Peripheral blood repopulation with HPV-reactive T cells also correlated with clinical response.
Conclusions:
These findings support the concept that cellular therapy can mediate the regression of epithelial cancers, and they suggest the importance of predictive biomarkers and novel treatment platforms for more effective therapies.
Data from Telomerase Activation and ATRX Mutations Are Independent Risk Factors for Metastatic Pheochromocytoma and Paraganglioma
Authors: Job Sylvie , Draskovic Irena , Burnichon Nelly , Buffet Alexandre , Cros Jérôme , Lépine Charles , Venisse Annabelle , Robidel Estelle , Verkarre Virginie , Meatchi Tchao , Sibony Mathilde , Amar Laurence , Bertherat Jérôme , de Reyniès Aurélien , Londoño-Vallejo Arturo , Favier Judith , Castro-Vega Luis Jaime , Gimenez-Roqueplo Anne-Paule
Published: April 2023

AbstractPurpose:
Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors. Whereas most PPGLs are benign, up to 20% may become metastatic with SDHB- and FH-mutated tumors showing the higher risk. We aimed at determining the contribution of immortalization mechanisms to metastatic progression.

Experimental Design: Immortalization mechanisms were investigated in 200 tumors. To identify telomerase (+) tumors, we analyzed genomic alterations leading to transcriptional activation of TERT comprising promoter mutations, hypermethylation and gain copy number. To identify tumors that activated the alternative lengthening of telomere (ALT) mechanism, we combined analyses of telomere length by slot blot, telomere heterogeneity by telomere FISH, and ATRX mutations by next-generation sequencing. Univariate/multivariate and metastasis-free survival (MFS) and overall survival (OS) analyses were carried out for assessment of risk factors and clinical outcomes.
Results:
Only 37 of 200 (18.5%) tumors achieved immortalization. Telomerase activation occurred in 12 metastatic tumors and was prevalent in SDHB-mutated paragangliomas (P = 2.42e−09). ALT features were present in 25 tumors, mostly pheochromocytomas, regardless of metastatic status or molecular group (P = 0.169), yet ATRX mutations were found preferentially in SDHB/FH-mutated metastatic tumors (P = 0.0014). Telomerase activation and ATRX mutations were independent factors of poor prognosis: MFS (hazard ratio, 48.2 and 33.1; P = 6.50E−07 and 1.90E−07, respectively); OS (hazard ratio, 97.4 and 44.1; P = 4.30E−03 and 2.00E−03, respectively) and were associated with worse MFS and OS (log-rank tests P < 0.0001).
Conclusions:
Assessment of telomerase activation and ATRX mutations could be used to identify metastatic PPGLs, particularly in tumors at high risk of progression.
Data from A Combinatorial Strategy for Targeting BRAFV600E-Mutant Cancers with BRAFV600E Inhibitor (PLX4720) and Tyrosine Kinase Inhibitor (Ponatinib)
Authors: Ghosh Chandrayee , Kumar Suresh , Kushchayeva Yevgeniya , Gaskins Kelli , Boufraqech Myriem , Wei Darmood , Gara Sudheer Kumar , Zhang Lisa , Zhang Ya-qin , Shen Min , Mukherjee Sanjit , Kebebew Electron
Published: April 2023

AbstractPurpose:
Most aggressive thyroid cancers are commonly associated with a BRAFV600E mutation. Preclinical and clinical data in BRAFV600E cancers suggest that combined BRAF and MEK inhibitor treatment results in a response, but resistance is common. One mechanism of acquired resistance is through persistent activation of tyrosine kinase (TK) signaling by alternate pathways. We hypothesized that combination therapy with BRAF and multitargeting TK inhibitors (MTKI) might be more effective in BRAFV600E thyroid cancer than in single-agent or BRAF and MEK inhibitors.
Experimental Design:
The combined drug activity was analyzed to predict any synergistic effect using high-throughput screening (HTS) of active drugs. We performed follow-up in vitro and in vivo studies to validate and determine the mechanism of action of synergistic drugs.
Results:
The MTKI ponatinib and the BRAF inhibitor PLX4720 showed synergistic activity by HTS. This combination significantly inhibited proliferation, colony formation, invasion, and migration in BRAFV600E thyroid cancer cell lines and downregulated pERK/MEK and c-JUN signaling pathways, and increased apoptosis. PLX4720-resistant BRAFV600E cells became sensitized to the combination treatment, with decreased proliferation at lower PLX4720 concentrations. In an orthotopic thyroid cancer mouse model, combination therapy significantly reduced tumor growth (P < 0.05), decreased the number of metastases (P < 0.05), and increased survival (P < 0.05) compared with monotherapy and vehicle control.
Conclusions:
Combination treatment with ponatinib and PLX4720 exhibited significant synergistic anticancer activity in preclinical models of BRAFV600E thyroid cancer, in addition to overcoming PLX4720 resistance. Our results suggest this combination should be tested in clinical trials.
Data from Baseline Plasma Tumor Mutation Burden Predicts Response to Pembrolizumab-based Therapy in Patients with Metastatic Non–Small Cell Lung Cancer
Authors: Aggarwal Charu , Thompson Jeffrey C. , Chien Austin L. , Quinn Katie J. , Hwang Wei-Ting , Black Taylor A. , Yee Stephanie S. , Christensen Theresa E. , LaRiviere Michael J. , Silva Benjamin A. , Banks Kimberly C. , Nagy Rebecca J. , Helman Elena , Berman Abigail T. , Ciunci Christine A. , Singh Aditi P. , Wasser Jeffrey S. , Bauml Joshua M. , Langer Corey J. , Cohen Roger B. , Carpenter Erica L.
Published: April 2023

AbstractPurpose:
The role of plasma-based tumor mutation burden (pTMB) in predicting response to pembrolizumab-based first-line standard-of-care therapy for metastatic non–small cell lung cancer (mNSCLC) has not been explored.
Experimental Design:
A 500-gene next-generation sequencing panel was used to assess pTMB. Sixty-six patients with newly diagnosed mNSCLC starting first-line pembrolizumab-based therapy, either alone or in combination with chemotherapy, were enrolled (Clinicaltrial.gov identifier: NCT03047616). Response was assessed using RECIST 1.1. Associations were made for patient characteristics, 6-month durable clinical benefit (DCB), progression-free survival (PFS), and overall survival (OS).
Results:
Of 66 patients, 52 (78.8%) were pTMB-evaluable. Median pTMB was 16.8 mutations per megabase (mut/Mb; range, 1.9–52.5) and was significantly higher for patients achieving DCB compared with no durable benefit (21.3 mut/Mb vs. 12.4 mut/Mb, P = 0.003). For patients with pTMB ≥ 16 mut/Mb, median PFS was 14.1 versus 4.7 months for patients with pTMB < 16 mut/Mb [HR, 0.30 (0.16–0.60); P < 0.001]. Median OS for patients with pTMB ≥ 16 was not reached versus 8.8 months for patients with pTMB < 16 mut/Mb [HR, 0.48 (0.22–1.03); P = 0.061]. Mutations in ERBB2 exon 20, STK11, KEAP1, or PTEN were more common in patients with no DCB. A combination of pTMB ≥ 16 and absence of negative predictor mutations was associated with PFS [HR, 0.24 (0.11–0.49); P < 0.001] and OS [HR, 0.31 (0.13–0.74); P = 0.009].
Conclusions:
pTMB ≥ 16 mut/Mb is associated with improved PFS after first-line standard-of-care pembrolizumab-based therapy in mNSCLC. STK11/KEAP1/PTEN and ERBB2 mutations may help identify pTMB-high patients unlikely to respond. These results should be validated in larger prospective studies.
Data from RABL6A Is an Essential Driver of MPNSTs that Negatively Regulates the RB1 Pathway and Sensitizes Tumor Cells to CDK4/6 Inhibitors
Authors: Kohlmeyer Jordan L. , Kaemmer Courtney A. , Pulliam Casey , Maharjan Chandra K. , Samayoa Allison Moreno , Major Heather J. , Cornick Kendall E. , Knepper-Adrian Vickie , Khanna Rajesh , Sieren Jessica C. , Leidinger Mariah R. , Meyerholz David K. , Zamba K.D. , Weimer Jill M. , Dodd Rebecca D. , Darbro Benjamin W. , Tanas Munir R. , Quelle Dawn E.
Published: April 2023

AbstractPurpose:
Malignant peripheral nerve sheath tumors (MPNST) are deadly sarcomas that lack effective therapies. In most MPNSTs, the retinoblastoma (RB1) tumor suppressor is disabled by hyperactivation of cyclin-dependent kinases (CDK), commonly through loss of CDK-inhibitory proteins such as p27(Kip1). RABL6A is an inhibitor of RB1 whose role in MPNSTs is unknown. To gain insight into MPNST development and establish new treatment options, we investigated RABL6A-RB1 signaling and CDK inhibitor–based therapy in MPNSTs.
Experimental Design:
We examined patient-matched MPNSTs and precursor lesions by RNA sequencing (RNA-Seq) and IHC. Molecular and biological effects of silencing RABL6A and/or p27 in MPNST lines and normal human Schwann cells were determined. Tumor-suppressive effects of CDK inhibitors were measured in MPNST cells and orthotopic tumors.
Results:
RABL6A was dramatically upregulated in human MPNSTs compared with precursor lesions, which correlated inversely with p27 levels. Silencing RABL6A caused MPNST cell death and G1 arrest that coincided with p27 upregulation, CDK downregulation, and RB1 activation. The growth-suppressive effects of RABL6A loss, and its regulation of RB1, were largely rescued by p27 depletion. Importantly, reactivation of RB1 using a CDK4/6 inhibitor (palbociclib) killed MPNST cells in vitro in an RABL6A-dependent manner and suppressed MPNST growth in vivo. Low-dose combination of drugs targeting multiple RB1 kinases (CDK4/6, CDK2) had enhanced antitumorigenic activity associated with potential MPNST cell redifferentiation.
Conclusions:
RABL6A is a new driver of MPNST pathogenesis that acts in part through p27-RB1 inactivation. Our results suggest RB1 targeted therapy with multiple pathway drugs may effectively treat MPNSTs.
Data from Targeted Brain Tumor Radiotherapy Using an Auger Emitter
Authors: Pirovano Giacomo , Jannetti Stephen A. , Carter Lukas M. , Sadique Ahmad , Kossatz Susanne , Guru Navjot , Demétrio De Souza França Paula , Maeda Masatomo , Zeglis Brian M. , Lewis Jason S. , Humm John L. , Reiner Thomas
Published: April 2023

AbstractPurpose:
Glioblastoma multiforme is a highly aggressive form of brain cancer whose location, tendency to infiltrate healthy surrounding tissue, and heterogeneity significantly limit survival, with scant progress having been made in recent decades.
Experimental Design:
123I-MAPi (Iodine-123 Meitner-Auger PARP1 inhibitor) is a precise therapeutic tool composed of a PARP1 inhibitor radiolabeled with an Auger- and gamma-emitting iodine isotope. Here, the PARP inhibitor, which binds to the DNA repair enzyme PARP1, specifically targets cancer cells, sparing healthy tissue, and carries a radioactive payload within reach of the cancer cells' DNA.
Results:
The high relative biological efficacy of Auger electrons within their short range of action is leveraged to inflict DNA damage and cell death with high precision. The gamma ray emission of 123I-MAPi allows for the imaging of tumor progression and therapy response, and for patient dosimetry calculation. Here we demonstrated the efficacy and specificity of this small-molecule radiotheranostic in a complex preclinical model. In vitro and in vivo studies demonstrate high tumor uptake and a prolonged survival in mice treated with 123I-MAPi when compared with vehicle controls. Different methods of drug delivery were investigated to develop this technology for clinical applications, including convection enhanced delivery and intrathecal injection.
Conclusions:
Taken together, these results represent the first full characterization of an Auger-emitting PARP inhibitor which demonstrate a survival benefit in mouse models of GBM and confirm the high potential of 123I-MAPi for clinical translation.
Data from Serum Alpha-fetoprotein Levels and Clinical Outcomes in the Phase III CELESTIAL Study of Cabozantinib versus Placebo in Patients with Advanced Hepatocellular Carcinoma
Authors: Kelley Robin Kate , Meyer Tim , Rimassa Lorenza , Merle Philippe , Park Joong-Won , Yau Thomas , Chan Stephen L. , Blanc Jean-Frederic , Tam Vincent C. , Tran Albert , Dadduzio Vincenzo , Markby David W. , Kaldate Rajesh , Cheng Ann-Lii , El-Khoueiry Anthony B. , Abou-Alfa Ghassan K.
Published: April 2023

AbstractPurpose:
The phase III CELESTIAL study demonstrated improved overall survival (OS) and progression-free survival (PFS) with cabozantinib versus placebo in patients with previously treated, advanced hepatocellular carcinoma (HCC). We analyzed outcomes by baseline alpha-fetoprotein (AFP) and on-treatment AFP changes.
Patients and Methods:
Serum AFP was measured every 8 weeks by blinded, centralized testing. Outcomes were analyzed by baseline AFP bifurcated at 400 ng/mL and by on-treatment AFP response (≥20% decrease from baseline at Week 8). The optimal cutoff for change in AFP at Week 8 was evaluated using maximally selected rank statistics.
Results:
Median OS for cabozantinib versus placebo was 13.9 versus 10.3 months [HR, 0.81; 95% confidence interval (CI), 0.62–1.04] for patients with baseline AFP <400 ng/mL, and 8.5 versus 5.2 months (HR, 0.71; 95% CI, 0.54–0.94) for patients with baseline AFP ≥400 ng/mL. Week 8 AFP response rate was 50% for cabozantinib versus 13% for placebo. In the cabozantinib arm, median OS for patients with and without AFP response was 16.1 versus 9.1 months (HR, 0.61; 95% CI, 0.45–0.84). AFP response was independently associated with longer OS. The optimal cutoff for association with OS in the cabozantinib arm was ≤0% change in AFP at Week 8 [AFP control; HR 0.50 (95% CI, 0.35–0.71)]. HRs for PFS were consistent with those for OS.
Conclusions:
Cabozantinib improved outcomes versus placebo across a range of baseline AFP levels. On-treatment AFP response and control rates were higher with cabozantinib than placebo, and were associated with longer OS and PFS with cabozantinib.
Data from Integrative Molecular Characterization of Resistance to Neoadjuvant Chemoradiation in Rectal Cancer
Authors: Kamran Sophia C. , Lennerz Jochen K. , Margolis Claire A. , Liu David , Reardon Brendan , Wankowicz Stephanie A. , Van Seventer Emily E. , Tracy Adam , Wo Jennifer Y. , Carter Scott L. , Willers Henning , Corcoran Ryan B. , Hong Theodore S. , Van Allen Eliezer M.
Published: April 2023

AbstractPurpose:
Molecular properties associated with complete response or acquired resistance to concurrent chemotherapy and radiotherapy (CRT) are incompletely characterized.

Experimental Design: We performed integrated whole-exome/transcriptome sequencing and immune infiltrate analysis on rectal adenocarcinoma tumors prior to neoadjuvant CRT (pre-CRT) and at time of resection (post-CRT) in 17 patients [8 complete/partial responders, 9 nonresponders (NR)].
Results:
CRT was not associated with increased tumor mutational burden or neoantigen load and did not alter the distribution of established somatic tumor mutations in rectal cancer. Concurrent KRAS/TP53 mutations (KP) associated with NR tumors and were enriched for an epithelial–mesenchymal transition transcriptional program. Furthermore, NR was associated with reduced CD4/CD8 T-cell infiltrates and a post-CRT M2 macrophage phenotype. Absence of any local tumor recurrences, KP/NR status predicted worse progression-free survival, suggesting that local immune escape during or after CRT with specific genomic features contributes to distant progression.
Conclusions:
Overall, while CRT did not impact genomic profiles, CRT impacted the tumor immune microenvironment, particularly in resistant cases.
Data from Response to Anti-EGFR Therapy in Patients with BRAF non-V600–Mutant Metastatic Colorectal Cancer
Authors: Yaeger Rona , Kotani Daisuke , Mondaca Sebastián , Parikh Aparna R. , Bando Hideaki , Van Seventer Emily E. , Taniguchi Hiroya , Zhao HuiYong , Thant Claire N. , de Stanchina Elisa , Rosen Neal , Corcoran Ryan B. , Yoshino Takayuki , Yao Zhan , Ebi Hiromichi
Published: April 2023

AbstractPurpose:
While mutations in BRAF in metastatic colorectal cancer (mCRC) most commonly occur at the V600 amino acid, with the advent of next-generation sequencing, non-V600 BRAF mutations are increasingly identified in clinical practice. It is unclear whether these mutants, like BRAF V600E, confer resistance to anti-EGFR therapy.
Experimental Design:
We conducted a multicenter pooled analysis of consecutive patients with non-V600 BRAF-mutated mCRCs identified between 2010 and 2017. Non-V600 BRAF mutations were divided into functional classes based on signaling mechanism and kinase activity: activating and RAS-independent (class 2) or kinase-impaired and RAS-dependent (class 3).
Results:
Forty patients with oncogenic non-V600 BRAF–mutant mCRC received anti-EGFR antibody treatment [n = 12 (30%) class 2 and n = 28 (70%) class 3]. No significant differences in clinical characteristics were observed by mutation class. In contrast, while only 1 of 12 patients with class 2 BRAF mCRC responded, 14 of 28 patients with class 3 BRAF responded to anti-EGFR therapy (response rate, 8% and 50%, respectively, P = 0.02). Specifically, in first- or second-line, 1 of 6 (17%) patients with class 2 and 7 of 9 (78%) patients with class 3 BRAF mutants responded (P = 0.04). In third- or later-line, none of 6 patients with class 2 and 7 of 19 (37%) patients with class 3 BRAF mutants responded (P = 0.14).
Conclusions:
Response to EGFR antibody treatment in mCRCs with class 2 BRAF mutants is rare, while a large portion of CRCs with class 3 BRAF mutants respond. Patients with colorectal cancer with class 3 BRAF mutations should be considered for anti-EGFR antibody treatment.

See related commentary by Fontana and Valeri, p. 6896
Data from Impact of BRAF Mutation Class on Disease Characteristics and Clinical Outcomes in BRAF-mutant Lung Cancer
Authors: Dagogo-Jack Ibiayi , Martinez Pablo , Yeap Beow Y. , Ambrogio Chiara , Ferris Lorin A. , Lydon Christine , Nguyen Tom , Jessop Nicholas A. , Iafrate A. John , Johnson Bruce E. , Lennerz Jochen K. , Shaw Alice T. , Awad Mark M.
Published: April 2023

AbstractPurpose:
BRAF mutations are divided into functional classes distinguished by signaling mechanism and kinase activity: V600-mutant kinase-activating monomers (class I), kinase-activating dimers (class II), and kinase-inactivating heterodimers (class III). The relationship between functional class and disease characteristics in BRAF-mutant non–small cell lung cancer (NSCLC) has not been fully explored.
Experimental Design:
We performed a retrospective analysis of BRAF-mutant NSCLCs treated at 2 institutions from 2005 to 2017 to determine clinicopathologic characteristics, progression-free survival (PFS) on chemotherapy, and overall survival (OS).
Results:
We identified 236 patients with BRAF-mutant NSCLC (n = 107 class I, n = 75 class II, and n = 54 class III). Patients with class II or III mutations were more likely to have brain metastases (P ≤ 0.01) and RAS coalterations (P ≤ 0.001) than class I. Compared with class I, PFS on chemotherapy was shorter for class II (P = 0.069) and class III (P = 0.034). OS was shorter for class II and III (class I, 40.1 months; class II, 13.9 months; and class III, 15.6 months; I vs. II, P < 0.001; I vs. III, P = 0.023); however, this difference was driven by fewer extrathoracic metastases and higher use of targeted therapies in class I patients. When patients treated with targeted therapy and those with thoracic-only metastases were excluded, there was no difference in OS across the 3 classes.
Conclusions:
BRAF-mutant NSCLC is a heterogeneous disease that encompasses 3 distinct functional classes. Classes II and III have more aggressive clinical features leading to less favorable outcomes. The distinct biological characteristics of class II and III tumors suggest that class-specific therapies may be necessary to effectively target these molecular subsets.
Data from Wee1 Kinase Inhibitor AZD1775 Effectively Sensitizes Esophageal Cancer to Radiotherapy
Authors: Yang Linlin , Shen Changxian , Pettit Cory J. , Li Tianyun , Hu Andrew J. , Miller Eric D. , Zhang Junran , Lin Steven H. , Williams Terence M.
Published: April 2023

AbstractPurpose:
Esophageal cancer is a deadly malignancy with a 5-year survival rate of only 5% to 20%, which has remained unchanged for decades. Esophageal cancer possesses a high frequency of TP53 mutations leading to dysfunctional G1 cell-cycle checkpoint, which likely makes esophageal cancer cells highly reliant upon G2–M checkpoint for adaptation to DNA replication stress and DNA damage after radiation. We aim to explore whether targeting Wee1 kinase to abolish G2–M checkpoint sensitizes esophageal cancer cells to radiotherapy.
Experimental Design:
Cell viability was assessed by cytotoxicity and colony-forming assays, cell-cycle distribution was analyzed by flow cytometry, and mitotic catastrophe was assessed by immunofluorescence staining. Human esophageal cancer xenografts were generated to explore the radiosensitizing effect of AZD1775 in vivo.
Results:
The IC50 concentrations of AZD1775 on esophageal cancer cell lines were between 300 and 600 nmol/L. AZD1775 (100 nmol/L) as monotherapy did not alter the viability of esophageal cancer cells, but significantly radiosensitized esophageal cancer cells. AZD1775 significantly abrogated radiation-induced G2–M phase arrest and attenuation of p-CDK1-Y15. Moreover, AZD1775 increased radiation-induced mitotic catastrophe, which was accompanied by increased γH2AX levels, and subsequently reduced survival after radiation. Importantly, AZD1775 in combination with radiotherapy resulted in marked tumor regression of esophageal cancer tumor xenografts.
Conclusions:
Abrogation of G2–M checkpoint by targeting Wee1 kinase with AZD1775 sensitizes esophageal cancer cells to radiotherapy in vitro and in mouse xenografts. Our findings suggest that inhibition of Wee1 by AZD1775 is an effective strategy for radiosensitization in esophageal cancer and warrants clinical testing.
Data from Talazoparib Is a Potent Radiosensitizer in Small Cell Lung Cancer Cell Lines and Xenografts
Authors: Laird James H. , Lok Benjamin H. , Ma Jennifer , Bell Andrew , de Stanchina Elisa , Poirier John T. , Rudin Charles M.
Published: April 2023

Abstract
Purpose: Small cell lung cancer (SCLC) is an aggressive malignancy with a critical need for novel therapies. Our goal was to determine whether PARP inhibition could sensitize SCLC cells to ionizing radiation (IR) and if so, to determine the contribution of PARP trapping to radiosensitization.

Experimental Design: Short-term viability assays and clonogenic survival assays (CSA) were used to assess radiosensitization in 6 SCLC cell lines. Doses of veliparib and talazoparib with equivalent enzymatic inhibitory activity but differing PARP trapping activity were identified and compared in CSAs. Talazoparib, IR, and their combination were tested in three patient-derived xenograft (PDX) models.

Results: Talazoparib radiosensitized 5 of 6 SCLC cell lines in short-term viability assays and confirmed in 3 of 3 cell lines by CSAs. Concentrations of 200 nmol/L talazoparib and 1,600 nmol/L veliparib similarly inhibited PAR polymerization; however, talazoparib exhibited greater PARP trapping activity that was associated with superior radiosensitization. This observation further correlated with an increased number of double-stranded DNA breaks induced by talazoparib as compared with veliparib. Finally, a dose of 0.2 mg/kg talazoparib in vivo caused tumor growth inhibition in combination with IR but not as a single agent in 3 SCLC PDX models.

Conclusions: PARP inhibition effectively sensitizes SCLC cell lines and PDXs to IR, and PARP trapping activity enhances this effect. PARP inhibitors, especially those with high PARP trapping activity, may provide a powerful tool to improve the efficacy of radiotherapy in SCLC. Clin Cancer Res; 24(20); 5143–52. ©2018 AACR.
Data from U.S. Phase I First-in-human Study of Taletrectinib (DS-6051b/AB-106), a ROS1/TRK Inhibitor, in Patients with Advanced Solid Tumors
Authors: Papadopoulos Kyriakos P. , Borazanci Erkut , Shaw Alice T. , Katayama Ryohei , Shimizu Yuki , Zhu Viola W. , Sun Thomas Yang , Wakelee Heather A. , Madison Russell , Schrock Alexa B. , Senaldi Giorgio , Nakao Naoki , Hanzawa Hiroyuki , Tachibana Masaya , Isoyama Takeshi , Nakamaru Kenji , Deng Chenhui , Li Meijing , Fan Frank , Zhao Qinying , Gao Yanfei , Seto Takashi , Jänne Pasi A. , Ou Sai-Hong Ignatius
Published: April 2023

AbstractPurpose:
Taletrectinib (DS-6051b/AB-106) is an oral, tyrosine kinase inhibitor of ROS1 and NTRK with potent preclinical activity against ROS1 G2032R solvent-front mutation among others. We report the first-in-human U.S. phase I results of taletrectinib.
Patients and Methods:
Patients ≥18 years old with neuroendocrine tumors, with tumor-induced pain, or tumors harboring ROS1/NTRK rearrangements were eligible. Accelerated titration followed by modified continuous reassessment method and escalation with overdose control was used (50–1,200 mg once daily or 400 mg twice daily). Primary objectives were safety/tolerability, and MTD determination. Secondary objectives were food-effect pharmacokinetics and antitumor activity.
Results:
A total of 46 patients were enrolled. Steady-state peak concentration (Cmax) and exposure (AUC0-8) increased dose dependently from 50-mg to 800-mg once-daily doses. The ratio of the geometric mean of AUC0-24 between low-fat-diet-fed/fasted state was 123% (90% confidence interval, 104%–149%). Dose-limiting toxicities (grade 3 transaminases increase) occurred in two patients (1,200-mg once-daily dose). MTD was 800 mg once daily. Most common treatment-related adverse events were nausea (47.8%), diarrhea (43.5%), and vomiting (32.6%). Pain score reductions were observed in the 800-mg once-daily dose cohort. Confirmed objective response rate was 33.3% among the six patients with RECIST-evaluable crizotinib-refractory ROS1+ NSCLC. One patient with TPM3-NTRK1 differentiated thyroid cancer achieving a confirmed partial response of 27 months at data cutoff. We identified a cabozantinib-sensitive ROS1 L2086F as an acquired taletrectinib-resistance mutation.
Conclusions:
Taletrectinib has manageable toxicities at the MTD of 800 mg daily. Preliminary efficacy was observed in patients with crizotinib-refractory ROS1+ NSCLC.
Data from Association of CD4+ Radiation-Induced Lymphocyte Apoptosis with Fibrosis and Telangiectasia after Radiotherapy in 272 Breast Cancer Patients with >10-Year Follow-up
Authors: Veldwijk Marlon R. , Seibold Petra , Botma Akke , Helmbold Irmgard , Sperk Elena , Giordano Frank A. , Gürth Nicole , Kirchner Anne , Behrens Sabine , Wenz Frederik , Chang-Claude Jenny , Herskind Carsten
Published: April 2023

AbstractPurpose:
Radiation-induced lymphocyte apoptosis (RILA) has been suggested as a predictive assay for adverse late reactions after radiotherapy. Thus, low RILA values of T-lymphocyte subpopulations have been associated with increased risk for various endpoints at 2 to 3 years of follow-up. The purpose was to test if such associations persist for specific endpoints (subcutaneous fibrosis, telangiectasia) in breast cancer patients with at least 10 years of follow-up.

Experimental Design: Two hundred and seventy-two female patients who had received breast-conserving therapy within the German ISE study were included (median follow-up: 11.6 years). Radiotherapy-induced side effects were scored according to the Late Effects in Normal Tissues-Subjective, Objective, Management, and Analytic (LENT-SOMA) classification system. RILA in the CD4+, CD8+, and natural killer (NK) subpopulations from peripheral blood was analyzed by flow cytometry. Multivariate predictive modeling was performed including relevant clinical risk factors.
Results:
Low CD4+ RILA was associated with increased risk for both fibrosis (P = 0.011) and telangiectasia (P < 0.001). For fibrosis, the association was stronger outside the surgical area (Fibout; P = 0.004) than within (Fibin; P = 0.17). Predictive multivariate modeling including clinical risk factors yielded OR of 3.48 (95% confidence interval, 1.84–6.58) for any fibrosis and 8.60 (2.71–27.3) for telangiectasia. Addition of CD4+ RILA to the clinical variables improved discrimination (c statistics) from 0.62 to 0.68 for any fibrosis, 0.62 to 0.66 for Fibin, 0.61 to 0.69 for Fibout, and from 0.65 to 0.76 for telangiectasia. CD8+ and NK RILA were not significantly associated with radiotherapy-related late reactions.
Conclusions:
The results provide first evidence that low CD4+ RILA is associated with increased subcutaneous fibrosis and telangiectasia even after 10 years. This supports the potential usefulness for predicting individual clinical risk.
Data from FS222, a CD137/PD-L1 Tetravalent Bispecific Antibody, Exhibits Low Toxicity and Antitumor Activity in Colorectal Cancer Models
Authors: Lakins Matthew A. , Koers Alexander , Giambalvo Raffaella , Munoz-Olaya Jose , Hughes Robert , Goodman Emma , Marshall Sylwia , Wollerton Francisca , Batey Sarah , Gliddon Daniel , Tuna Mihriban , Brewis Neil
Published: April 2023

AbstractPurpose:
With the increased prevalence in checkpoint therapy resistance, there remains a significant unmet need for additional therapies for patients with relapsing or refractory cancer. We have developed FS222, a bispecific tetravalent antibody targeting CD137 and PD-L1, to induce T-cell activation to eradicate tumors without the current toxicity and efficacy limitations seen in the clinic.
Experimental Design:
A bispecific antibody (FS222) was developed by engineering CD137 antigen–binding sites into the Fc region of a PD-L1 IgG1 mAb. T-cell activation by FS222 was investigated using multiple in vitro assays. The antitumor efficacy, survival benefit, pharmacodynamics, and liver pharmacology of a murine surrogate molecule were assessed in syngeneic mouse tumor models. Toxicology and the pharmacokinetic/pharmacodynamic profile of FS222 were investigated in a non-human primate dose-range finding study.
Results:
We demonstrated simultaneous binding of CD137 and PD-L1 and showed potent T-cell activation across CD8+ T-cell activation assays in a PD-L1–dependent manner with a CD137/PD-L1 bispecific antibody, FS222. FS222 also activated T cells in a human primary mixed lymphocyte reaction assay, with greater potency than the monospecific mAb combination. FS222 showed no signs of liver toxicity up to 30 mg/kg in a non-human primate dose-range finding study. A surrogate molecule caused significant tumor growth inhibition and survival benefit, concomitant with CD8+ T-cell activation, in CT26 and MC38 syngeneic mouse tumor models.
Conclusions:
By targeting CD137 agonism to areas of PD-L1 expression, predominantly found in the tumor microenvironment, FS222 has the potential to leverage a focused, potent, and safe immune response augmenting the PD-(L)1 axis blockade.