Systematic discovery of mutation-directed neo-protein-protein interactions in cancer.

Comprehensive sequencing of patient tumors reveals genomic mutations across tumor types that enable tumorigenesis and progression. A subset of oncogenic driver mutations results in neomorphic activity where the mutant protein mediates functions not engaged by the parental molecule. Here, we identify prevalent variant-enabled neomorph-protein-protein interactions (neoPPI) with a quantitative high-throughput differential screening (qHT-dS) platform. The coupling of highly sensitive BRET biosensors with miniaturized coexpression in an ultra-HTS format allows large-scale monitoring of the interactions of wild-type and mutant variant counterparts with a library of cancer-associated proteins in live cells. The screening of 17,792 interactions with 2,172,864 data points revealed a landscape of gain of interactions encompassing both oncogenic and tumor suppressor mutations. For example, the recurrent BRAF V600E lesion mediates KEAP1 neoPPI, rewiring a BRAFV600E/KEAP1 signaling axis and creating collateral vulnerability to NQO1 substrates, offering a combination therapeutic strategy. Thus, cancer genomic alterations can create neo-interactions, informing variant-directed therapeutic approaches for precision medicine.

An update on the immune landscape in lung and head and neck cancers.

Immunotherapy has dramatically changed the treatment landscape for patients with cancer. Programmed death-ligand 1/programmed death-1 checkpoint inhibitors have been in the forefront of this clinical revolution. Currently, there are 6 US Food and Drug Administration-approved checkpoint inhibitors for approximately 18 different histologic types of cancer. Lung cancer and head and neck squamous cell carcinoma (HNSCC) are 2 diseases that have led the way in the development of immunotherapy. Atezolizumab, durvalumab, nivolumab, and pembrolizumab are all currently used as part of standard-of-care treatment for different stages of lung cancer. Similarly, nivolumab and pembrolizumab have US regulatory approval as treatment for advanced metastatic HNSCC. This is significant because lung cancer represents the most common and most fatal cancer globally, and HNSCC is the sixth most common. Currently, most of the approvals for the use of immunotherapy agents are for patients diagnosed in the metastatic setting. However, research is ongoing to evaluate these drugs in earlier stage disease. There is plausible biological rationale to expect that pharmacologic activation of the immune system will be effective for early-stage and smaller tumors. In addition, selecting patients who are more likely to respond to immunotherapy and understanding why resistance develops are crucial areas of ongoing research. The objective of this review was to provide an overview of the current immune landscape and future directions in lung cancer and HNSCC.

Tarlatamab for Patients with Previously Treated Small-Cell Lung Cancer.

BACKGROUND: Tarlatamab, a bispecific T-cell engager immunotherapy targeting delta-like ligand 3 and CD3, showed promising antitumor activity in a phase 1 trial in patients with previously treated small-cell lung cancer. METHODS: In this phase 2 trial, we evaluated the antitumor activity and safety of tarlatamab, administered intravenously every 2 weeks at a dose of 10 mg or 100 mg, in patients with previously treated small-cell lung cancer. The primary end point was objective response (complete or partial response), as assessed by blinded independent central review according to the Response Evaluation Criteria in Solid Tumors, version 1.1. RESULTS: Overall, 220 patients received tarlatamab; patients had previously received a median of two lines of treatment. Among patients evaluated for antitumor activity and survival, the median follow-up was 10.6 months in the 10-mg group and 10.3 months in the 100-mg group. An objective response occurred in 40% (97.5% confidence interval [CI], 29 to 52) of the patients in the 10-mg group and in 32% (97.5% CI, 21 to 44) of those in the 100-mg group. Among patients with an objective response, the duration of response was at least 6 months in 59% (40 of 68 patients). Objective responses at the time of data cutoff were ongoing in 22 of 40 patients (55%) in the 10-mg group and in 16 of 28 patients (57%) in the 100-mg group. The median progression-free survival was 4.9 months (95% CI, 2.9 to 6.7) in the 10-mg group and 3.9 months (95% CI, 2.6 to 4.4) in the 100-mg group; the estimates of overall survival at 9 months were 68% and 66% of patients, respectively. The most common adverse events were cytokine-release syndrome (in 51% of the patients in the 10-mg group and in 61% of those in the 100-mg group), decreased appetite (in 29% and 44%, respectively), and pyrexia (in 35% and 33%). Cytokine-release syndrome occurred primarily during treatment cycle 1, and events in most of the patients were grade 1 or 2 in severity. Grade 3 cytokine-release syndrome occurred less frequently in the 10-mg group (in 1% of the patients) than in the 100-mg group (in 6%). A low percentage of patients (3%) discontinued tarlatamab because of treatment-related adverse events. CONCLUSIONS: Tarlatamab, administered as a 10-mg dose every 2 weeks, showed antitumor activity with durable objective responses and promising survival outcomes in patients with previously treated small-cell lung cancer. No new safety signals were identified. (Funded by Amgen; DeLLphi-301 ClinicalTrials.gov number, NCT05060016.).

The PLAG1-GDH1 Axis Promotes Anoikis Resistance and Tumor Metastasis through CamKK2-AMPK Signaling in LKB1-Deficient Lung Cancer.

Loss of LKB1 is associated with increased metastasis and poor prognosis in lung cancer, but the development of targeted agents is in its infancy. Here we report that a glutaminolytic enzyme, glutamate dehydrogenase 1 (GDH1), upregulated upon detachment via pleomorphic adenoma gene 1 (PLAG1), provides anti-anoikis and pro-metastatic signals in LKB1-deficient lung cancer. Mechanistically, the GDH1 product α-KG activates CamKK2 by enhancing its substrate AMPK binding, which contributes to energy production that confers anoikis resistance. The effect of GDH1 on AMPK is evident in LKB1-deficient lung cancer, where AMPK activation predominantly depends on CamKK2. Targeting GDH1 with R162 attenuated tumor metastasis in patient-derived xenograft model and correlation studies in lung cancer patients further validated the clinical relevance of our finding. Our study provides insight into the molecular mechanism by which GDH1-mediated metabolic reprogramming of glutaminolysis mediates lung cancer metastasis and offers a therapeutic strategy for patients with LKB1-deficient lung cancer.

Tetrameric Acetyl-CoA Acetyltransferase 1 Is Important for Tumor Growth.

Mitochondrial acetyl-CoA acetyltransferase 1 (ACAT1) regulates pyruvate dehydrogenase complex (PDC) by acetylating pyruvate dehydrogenase (PDH) and PDH phosphatase. How ACAT1 is "hijacked" to contribute to the Warburg effect in human cancer remains unclear. We found that active, tetrameric ACAT1 is commonly upregulated in cells stimulated by EGF and in diverse human cancer cells, where ACAT1 tetramers, but not monomers, are phosphorylated and stabilized by enhanced Y407 phosphorylation. Moreover, we identified arecoline hydrobromide (AH) as a covalent ACAT1 inhibitor that binds to and disrupts only ACAT1 tetramers. The resultant AH-bound ACAT1 monomers cannot reform tetramers. Inhibition of tetrameric ACAT1 by abolishing Y407 phosphorylation or AH treatment results in decreased ACAT1 activity, leading to increased PDC flux and oxidative phosphorylation with attenuated cancer cell proliferation and tumor growth. These findings provide a mechanistic understanding of how oncogenic events signal through distinct acetyltransferases to regulate cancer metabolism and suggest ACAT1 as an anti-cancer target.

Shifting Sociodemographic Characteristics of a Phase I Clinical Trial Population at an NCI-Designated Comprehensive Cancer Center in the Southeast.

Racial and ethnic minority populations are consistently under-represented in oncology clinical trials despite comprising a disproportionate share of a cancer burden. Phase I oncology clinical trials pose a unique challenge and opportunity for minority inclusion. Here we compared the sociodemographic characteristics of patients participating in phase 1 clinical trials a National Cancer Institute ( NCI)-designated comprehensive center to all patients at the center, patients with new cancer diagnosis in metropolitan Atlanta and patients with new cancer diagnoses in the state of Georgia. From 2015 to 2020, 2325 patients (43.4% female, 56.6% male) consented to participate in a phase I trial. Grouped self-reported race distribution was 70.3% White, 26.2% Black, and 3.5% other. Of new patient registrations at Winship Cancer Institute (N = 107 497) (50% F, 50% M), grouped race distribution was 63.3% White, 32.0% Black, and 4.7% other. Patients with new cancer diagnoses in metro Atlanta from 2015 to 2016 (N = 31101) were 58.4% White, 37.2% Black, and 4.3% other. Race and sex distribution of phase I patients was significantly different than Winship patients (P < .001). Over time, percent of White patients decreased in both phase I and Winship groups (P = .009 and P < .001, respectively); percentage of females did not change in either group (P = .54 phase I, P = .063 Winship). Although phase I patients were more likely to be White, male, and privately ensured than the Winship cohort, from 2015 to 2020 the percentage of White patients in phase I trials and among all new patients treated at Winship decreased. The intent of characterizing existing disparities is to improve the representation of patients from racial and ethnic minority backgrounds in phase I clinical trials.

Efficacy of Selpercatinib in RET-Altered Thyroid Cancers.

BACKGROUND: RET mutations occur in 70% of medullary thyroid cancers, and RET fusions occur rarely in other thyroid cancers. In patients with RET-altered thyroid cancers, the efficacy and safety of selective RET inhibition are unknown. METHODS: We enrolled patients with RET-mutant medullary thyroid cancer with or without previous vandetanib or cabozantinib treatment, as well as those with previously treated RET fusion-positive thyroid cancer, in a phase 1-2 trial of selpercatinib. The primary end point was an objective response (a complete or partial response), as determined by an independent review committee. Secondary end points included the duration of response, progression-free survival, and safety. RESULTS: In the first 55 consecutively enrolled patients with RET-mutant medullary thyroid cancer who had previously received vandetanib, cabozantinib, or both, the percentage who had a response was 69% (95% confidence interval [CI], 55 to 81), and 1-year progression-free survival was 82% (95% CI, 69 to 90). In 88 patients with RET-mutant medullary thyroid cancer who had not previously received vandetanib or cabozantinib, the percentage who had a response was 73% (95% CI, 62 to 82), and 1-year progression-free survival was 92% (95% CI, 82 to 97). In 19 patients with previously treated RET fusion-positive thyroid cancer, the percentage who had a response was 79% (95% CI, 54 to 94), and 1-year progression-free survival was 64% (95% CI, 37 to 82). The most common adverse events of grade 3 or higher were hypertension (in 21% of the patients), increased alanine aminotransferase level (in 11%), increased aspartate aminotransferase level (in 9%), hyponatremia (in 8%), and diarrhea (in 6%). Of all 531 patients treated, 12 (2%) discontinued selpercatinib owing to drug-related adverse events. CONCLUSIONS: In this phase 1-2 trial, selpercatinib showed durable efficacy with mainly low-grade toxic effects in patients with medullary thyroid cancer with and without previous vandetanib or cabozantinib treatment. (Funded by Loxo Oncology and others; LIBRETTO-001 ClinicalTrials.gov number, NCT03157128.).

Phase I trial of the DLL3/CD3 bispecific T-cell engager BI 764532 in DLL3-positive small-cell lung cancer and neuroendocrine carcinomas.

Poorly differentiated neuroendocrine carcinomas such as small-cell lung cancer (SCLC) have poor survival and high relapse rates. DLL3 is found on these carcinomas and has become a target of increasing interest in recent years. The bispecific DLL3/CD3 T-cell engager BI 764532 has been shown to induce complete tumor regression in a human T cell-engrafted mouse model. Here, we describe the study design of a first-in-human, phase I, multicenter, open-label, non-randomized, dose-escalation study in patients with SCLC or other DLL3-positive neuroendocrine carcinomas. The study will determine the maximum tolerated dose and evaluate safety, tolerability, pharmacokinetics and preliminary efficacy of BI 764532 monotherapy.

DLL3 is a protein involved in development of the embryo during pregnancy. It has also been found on the surface of cells involved in the development of certain types of lung cancer and other tumors. The T-cell engager BI 764532 binds to DLL3 and cells of the immune system simultaneously, resulting in the death of tumor cells. Here we describe the rationale for, and design of, a clinical study of BI 764532 in patients with small-cell lung cancer and other tumors containing DLL3. The aim of the study is to find the highest acceptable dose of BI 764532 that can be tolerated by patients, and explore the safety and efficacy of BI 764532. Clinical Trial Registration: NCT04429087 (ClinicalTrials.gov).

Physician Communication and Patient Understanding of Molecular Testing Terminology.

BACKGROUND: The use of molecular testing in oncology is rapidly expanding. The aim of this study was to determine how oncologists describe molecular testing and whether patients understand the terminology being used. MATERIALS AND METHODS: Sixty conversations between oncologists and patients about molecular testing were observed, and the used technical terms were noted by the researcher. Patients were interviewed post-conversation to assess their understanding of the noted technical terms. A patient understanding score was calculated for each participant. Comparisons of the terms were conducted using χ2 tests, Fisher's exact tests, or ANOVA when appropriate. RESULTS: Sixty-one unique technical terms were used by oncologists, to describe seven topics. "Mutation" was a challenging term for patients to understand with 48.8% (21/43 mentions) of participants correctly defining the term. "Genetic testing" and "Gene" were understood a little more than half the time (53.3%; 8/15 and 56.4%; 22/39 respectively). "DNA" was well understood (80%; 12/15). There was no correlation between the terms being defined by the oncologist in the conversation, and the likelihood of the patient providing a correct definition. White participants were significantly more likely to understand both "mutation" and "genetic testing" than non-White participants. Forty-two percent (n = 25) of participants had an understanding score below 50%, and a higher family income was significantly correlated with a higher score. CONCLUSION: Our results show that oncologists use variable terminology to describe molecular testing, which is often not understood. Because oncologists defining the terms did not correlate with understanding, it is imperative to develop new, improved methods to explain molecular testing. IMPLICATIONS FOR PRACTICE: The use of molecular testing is expanding in oncology, yet little is known about how effectively clinicians are communicating information about molecular testing and whether patients understand the terminology used. The results of this study indicate that patients do not understand some of the terminology used by their clinicians and that clinicians tend to use highly variable terminology to describe molecular testing. These results highlight the need to develop and implement effective methods to explain molecular testing terminology to patients to ensure that patients have the tools to make autonomous and informed decisions about their treatment.

Phase I Trial of Cemiplimab, Radiotherapy, Cyclophosphamide, and Granulocyte Macrophage Colony-Stimulating Factor in Patients with Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma.

LESSONS LEARNED: Cemiplimab in combination with radiation therapy, cyclophosphamide, and granulocyte macrophage colony-stimulating factor did not demonstrate efficacy above what can be achieved with other PD-1 inhibitor monotherapies in patients with refractory and metastatic head and neck squamous cell carcinoma. The safety profile of cemiplimab combination therapy was consistent with previously reported safety profiles of cemiplimab monotherapy. No new safety signal was observed. BACKGROUND: Refractory and metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) generally does not respond to PD-1 inhibitor monotherapy. Cemiplimab is a human anti-PD-1 monoclonal antibody. An expansion cohort enrolled patients with R/M HNSCC in a phase I study combining cemiplimab plus radiation therapy (RT), cyclophosphamide, and granulocyte macrophage colony-stimulating factor (GM-CSF). METHODS: Patients with R/M HNSCC refractory to at least first-line therapy and for whom palliative RT is clinically indicated received cemiplimab plus RT, cyclophosphamide, and GM-CSF. The co-primary objectives were the safety, tolerability, and efficacy of cemiplimab plus RT, cyclophosphamide, and GM-CSF in 15 patients with R/M HNSCC. RESULTS: Fifteen patients were enrolled. Patients discontinued treatment due to progression of disease. The most common treatment-emergent adverse events (TEAEs) of any grade were fatigue (40.0%), constipation (26.7%), and asthenia, dyspnea, maculo-papular rash, and pneumonia (each 20%). The only grade ≥3 TEAE that occurred in two patients was pneumonia (13.3%). By investigator assessment, there was one partial response (6.7%); disease control rate was 40.0% (95% confidence interval [CI], 16.3-67.7; five patients with stable disease); seven patients had progressive disease, and two were not evaluable. Median progression-free survival by investigator assessment was 1.8 months (95% CI, 1.7-4.7). CONCLUSION: The regimen demonstrated tolerability but not efficacy above that which can be achieved with anti-PD-1 inhibitor monotherapy for R/M HNSCC.

PD-1 Blockade with Cemiplimab in Advanced Cutaneous Squamous-Cell Carcinoma.

BACKGROUND: No systemic therapies have been approved for the treatment of advanced cutaneous squamous-cell carcinoma. This cancer may be responsive to immune therapy, because the mutation burden of the tumor is high and the disease risk is strongly associated with immunosuppression. In the dose-escalation portion of the phase 1 study of cemiplimab, a deep and durable response was observed in a patient with metastatic cutaneous squamous-cell carcinoma. METHODS: We report the results of the phase 1 study of cemiplimab for expansion cohorts of patients with locally advanced or metastatic cutaneous squamous-cell carcinoma, as well as the results of the pivotal phase 2 study for a cohort of patients with metastatic disease (metastatic-disease cohort). In both studies, the patients received an intravenous dose of cemiplimab (3 mg per kilogram of body weight) every 2 weeks and were assessed for a response every 8 weeks. In the phase 2 study, the primary end point was the response rate, as assessed by independent central review. RESULTS: In the expansion cohorts of the phase 1 study, a response to cemiplimab was observed in 13 of 26 patients (50%; 95% confidence interval [CI], 30 to 70). In the metastatic-disease cohort of the phase 2 study, a response was observed in 28 of 59 patients (47%; 95% CI, 34 to 61). The median follow-up was 7.9 months in the metastatic-disease cohort of the phase 2 study. Among the 28 patients who had a response, the duration of response exceeded 6 months in 57%, and 82% continued to have a response and to receive cemiplimab at the time of data cutoff. Adverse events that occurred in at least 15% of the patients in the metastatic-disease cohort of the phase 2 study were diarrhea, fatigue, nausea, constipation, and rash; 7% of the patients discontinued treatment because of an adverse event. CONCLUSIONS: Among patients with advanced cutaneous squamous-cell carcinoma, cemiplimab induced a response in approximately half the patients and was associated with adverse events that usually occur with immune checkpoint inhibitors. (Funded by Regeneron Pharmaceuticals and Sanofi; ClinicalTrials.gov numbers, NCT02383212 and NCT02760498 .).

Evaluating the impact of the Patient Preference Assessment Tool on clinicians' recommendations for phase I oncology clinical trials.

OBJECTIVE: Many groups recommend assessment of patient preferences particularly for patients with advanced, incurable cancer. We, therefore, developed the Patient Preference Assessment Tool (PPAT) to ascertain patient preferences in order to inform clinician recommendations and improve shared decision-making. The aim of this study is to assess the PPAT's impact on clinicians' strength of recommendations for phase I oncology clinical trials. METHODS: Clinicians recorded the strength of their recommendation on a Likert scale before viewing the patient's PPAT. After viewing the PPAT, the clinician discussed the clinical trial with the patient and then recorded the strength of recommendation again. If there was a change, the clinician noted the reason for the change: clinical findings or patient preference. Clinicians were interviewed about the acceptability of the tool. Our threshold for determining if a change in recommendation due to the PPAT was significant was 20%, given the multiple factors influencing a clinician's recommendation. We also noted the type of phase I conversation observed based on classifications defined in prior work-priming, treatment-options, trial logistics, consent. RESULTS: N = 29. The strength of the clinicians' recommendations changed due to patient preferences in 7 of 29 (24%) of the conversations. The seven changes due to preferences were all in the 23 treatment-options conversations, for an impact rate of 30% in this type of conversation. 82% of clinicians found the PPAT useful. CONCLUSION: The PPAT was impactful in an academic setting, exceeding our 20% impact threshold. This tool helps achieve the important goal of incorporating patient preferences into shared decision-making about clinical trials.

Benefits and limitations of real-world evidence: lessons from EGFR mutation-positive non-small-cell lung cancer.

While randomized controlled trials (RCTs) are the gold standard for evidence-based medicine, they do not always reflect real-world patient populations, limiting their generalizability and external validity. Real-world evidence (RWE), generated during routine clinical practice, is increasingly important in determining effectiveness outside of the tightly controlled conditions of RCTs, and is now recognized by regulatory bodies as a valuable complement to RCTs. Consequently, it is increasingly important for physicians to understand how RWE data can be used alongside clinical trial data. Here, we discuss the different types of real-world observational studies, outline the benefits and limitations of RWE, and, using examples from EGFR mutation-positive non-small-cell lung cancer, outline how RWE can be used to help inform treatment decisions.

ERK inhibition effectively overcomes acquired resistance of epidermal growth factor receptor-mutant non-small cell lung cancer cells to osimertinib.

BACKGROUND: Osimertinib (AZD9291), a third-generation, mutation-selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (EGFR-TKI), is an approved drug for patients who have non-small cell lung cancer (NSCLC) with activating EGFR mutations or those harboring a resistant T790M mutation. Unfortunately, all patients eventually relapse and develop resistance to osimertinib. The current study addressed whether ERK inhibition exerts effects similar to those produced by MEK inhibition in overcoming acquired resistance to osimertinib. METHODS: Drug effects on cell and tumor growth were assessed by measuring cell number alterations and colony formation in vitro and with xenografts in nude mice in vivo. Apoptosis was assessed with annexin V/flow cytometry and protein cleavage. Protein alterations in cells were detected with Western blot analysis. Gene overexpression and knockout were achieved with lentiviral infection and CRISPR/Cas9, respectively. RESULTS: The combination of osimertinib with an ERK inhibitor synergistically decreased the survival of osimertinib-resistant cell lines with enhanced induction of apoptosis and effectively inhibited the growth of osimertinib-resistant xenografts in nude mice. Moreover, the combination of an MEK or ERK inhibitor with a first-generation (eg, erlotinib) or second-generation (eg, afatinib) EGFR-TKI also very effectively inhibited the growth of osimertinib-resistant cells in vitro and of tumors in vivo, although these cell lines were cross-resistant to first-generation or second-generation EGFR-TKIs. CONCLUSIONS: The current findings emphasize the importance of targeting MEK/ERK signaling in maintaining the long-term benefit of osimertinib through overcoming acquired resistance to osimertinib, warranting further investigation of this therapeutic strategy to improve the therapeutic efficacy of osimertinib in the clinic.

MEK or ERK inhibition effectively abrogates emergence of acquired osimertinib resistance in the treatment of epidermal growth factor receptor-mutant lung cancers.

BACKGROUND: The majority of patients with non-small cell lung cancer (NSCLC) harboring activating epidermal growth factor receptor (EGFR) mutations respond well to osimertinib (AZD9291), a third-generation, mutation-selective EGFR inhibitor. The current study focuses on determining whether targeting MEK/ERK signaling prevents or delays the development of acquired resistance to osimertinib. METHODS: Drug effects on cell survival were determined by measuring cell number alterations. Apoptosis was assessed with flow cytometry for the detection of annexin V-positive cells and with Western blotting for protein cleavage. Alterations of proteins in cells were detected with Western blotting. Drug effects on delaying the emergence of osimertinib resistance were evaluated with colony formation in vitro and xenografts in nude mice in vivo. RESULTS: Osimertinib combined with an MEK or ERK inhibitor synergistically decreased cell survival with enhanced induction of apoptosis in EGFR-mutant NSCLC cells but not in EGFR wild-type NSCLC cells. These combinations were also very effective in killing cell clones with primary intrinsic resistance to osimertinib. Continuous and intermittent pharmacologic inhibition of MEK/ERK signaling delayed the emergence of osimertinib resistance both in vitro and in vivo. CONCLUSIONS: These results provide strong preclinical evidence in support of targeting MEK/ERK signaling as a strategy for delaying or preventing acquired resistance to osimertinib in the clinic to improve the long-term therapeutic efficacy of osimertinib. From a clinical standpoint, the data support the evaluation of an intermittent treatment schedule of osimertinib in combination with an MEK or ERK inhibitor in patients with EGFR-mutated NSCLC.

Overcoming acquired resistance of epidermal growth factor receptor-mutant non-small cell lung cancer cells to osimertinib by combining osimertinib with the histone deacetylase inhibitor panobinostat (LBH589).

BACKGROUND: The major clinical obstacle that limits the long-term benefits of treatment with osimertinib (AZD9291) in patients with epidermal growth factor receptor-mutant non-small cell lung cancer is the development of acquired resistance. Therefore, effective strategies that can overcome acquired resistance to osimertinib are urgently needed. The authors' current efforts in this direction have identified LBH589 (panobinostat), a clinically used histone deacetylase inhibitor, as a potential agent in overcoming osimertinib resistance. METHODS: Cell growth and apoptosis in vitro were evaluated by measuring cell numbers and colony formation and by detecting annexin V-positive cells and protein cleavage, respectively. Drug effects on tumor growth in vivo were assessed with xenografts in nude mice. Alterations of tested proteins in cells were monitored with Western blot analysis. Gene knockout was achieved using the CRISPR/Cas9 technique. RESULTS: The combination of LBH589 and osimertinib synergistically decreased the survival of different osimertinib-resistant cell lines, including those harboring C797S mutations, with greater inhibition of cell colony formation and growth. The combination enhanced the induction of apoptosis in osimertinib-resistant cells. Importantly, the combination effectively inhibited the growth of osimertinib-resistant xenograft tumors in nude mice. Mechanistically, the combination of LBH589 and osimertinib enhanced the elevation of Bim in osimertinib-resistant cells. Knockout of Bim in osimertinib-resistant cells substantially attenuated or abolished apoptosis enhanced by the LBH589 and osimertinib combination. These results collectively support a critical role of Bim elevation in the induction of apoptosis of osimertinib-resistant cells for this combination. CONCLUSIONS: The current findings provide strong preclinical evidence in support of the potential for LBH589 to overcome osimertinib resistance in the clinic.

Efficacy and safety of immune checkpoint blockade in self-identified Black patients with advanced non-small cell lung cancer.

BACKGROUND: To the authors' knowledge, race-based differences in efficacy for the treatment of patients with advanced non-small cell lung cancer (NSCLC) have not been studied to date due to the underrepresentation of patients of minority backgrounds in pivotal trials. In the current study, the authors examined real-world differences in outcome in a diverse patient population. METHODS: The authors retrospectively analyzed the clinical outcomes of patients with advanced NSCLC who were treated with single-agent immune checkpoint blockade (ICB) between 2013 and July 2018 at Winship Cancer Institute of Emory University in Atlanta, Georgia. Primary efficacy comparison between Black patients and White patients was performed using bivariate and multivariate analyses for overall survival (OS) and progression-free survival (PFS). RESULTS: Data from 257 patients were analyzed. The median age of the patients was 69 years; 50.6% of the patients were female, 63.4% were White, 29.5% were Black, and 7.1% of the patients were of "other" race. ICB was the first-line treatment in 51 patients (19.9%), the second-line treatment in 161 patients (62.6%), and the third-line treatment in 33 patients (12.9%). The most commonly used agents were nivolumab (49.0%), pembrolizumab (25.2%), and atezolizumab (21.3%). No differences with regard to OS (P = .839) and PFS (P = .235) were noted between Black and White patients. The sample overall response rate was 20.6% (15.2% in Black patients and 23.1% in White patients). No differences with regard to OS (P = .081) and PFS (P = .176) were observed between female and male patients. The rate of immune-related adverse events was found to be similar in Black and White patients (20.0% vs 29.9%; P = .148). On multivariate analysis, race was not found to be significantly associated with OS or PFS. CONCLUSIONS: Real-world analysis of the authors' institutional experience demonstrated similar efficacy and tolerability of ICB in Black versus White patients with advanced NSCLC. Larger multi-institutional studies including other US minority populations would make the findings of the current study more generalizable.

Prognostic significance of an invasive leader cell-derived mutation cluster on chromosome 16q.

BACKGROUND: Intratumoral heterogeneity is defined by subpopulations with varying genotypes and phenotypes. Specialized, highly invasive leader cells and less invasive follower cells are phenotypically distinct subpopulations that cooperate during collective cancer invasion. Because leader cells are a rare subpopulation that would be missed by bulk sequencing, a novel image-guided genomics platform was used to precisely select this subpopulation. This study identified a novel leader cell mutation signature and tested its ability to predict prognosis in non-small cell lung cancer (NSCLC) patient cohorts. METHODS: Spatiotemporal genomic and cellular analysis was used to isolate and perform RNA sequencing on leader and follower populations from the H1299 NSCLC cell line, and it revealed a leader-specific mutation cluster on chromosome 16q. Genomic data from patients with lung squamous cell carcinoma (LUSC; n = 475) and lung adenocarcinoma (LUAD; n = 501) from The Cancer Genome Atlas were stratified by 16q mutation cluster (16qMC) status (16qMC+ vs 16qMC-) and compared for overall survival (OS), progression-free survival (PFS), and gene set enrichment analysis (GSEA). RESULTS: Poorer OS, poorer PFS, or both were found across all stages and among early-stage patients with 16qMC+ tumors within the LUSC and LUAD cohorts. GSEA revealed 16qMC+ tumors to be enriched for the expression of metastasis- and survival-associated gene sets. CONCLUSIONS: This represents the first leader cell mutation signature identified in patients and has the potential to better stratify high-risk NSCLC and ultimately improve patient outcomes.

Adiposity may predict survival in patients with advanced stage cancer treated with immunotherapy in phase 1 clinical trials.

BACKGROUND: Body mass index (BMI) is used to define obesity, but it is an imperfect measure of body composition. In the current study, the authors explored the association between types of fat and survival in patients treated with immunotherapy. METHODS: A retrospective analysis of 90 patients who were treated with immunotherapy on phase 1 clinical trials at the Winship Cancer Institute in Atlanta, Georgia, from 2009 through 2017 was performed. Overall survival (OS) and progression-free survival (PFS) were used to measure clinical outcomes. Baseline BMI and radiographic images at the middle of the third lumbar vertebrae were obtained. Fat densities were calculated and converted to indices (subcutaneous fat index [SFI], intermuscular fat index [IFI], and visceral fat index [VFI]) after dividing by height in meters squared. Risk groups were created using recursive partitioning and the regression trees method for SFI and IFI, which were selected by stepwise variable selection among all fat-related variables. The Cox proportional hazards model and Kaplan-Meier method were used for the association with OS and PFS. RESULTS: The majority of patients (59%) were male and diagnosed with melanoma (33%) or gastrointestinal cancers (22%). The median BMI was 27.4 kg/m2 , the median SFI was 62.78, the median IFI was 4.06, and the median VFI was 40.53. Low-risk patients (those with an SFI ≥73) had a significantly longer OS (hazard ratio, 0.20; 95% CI, 0.09-0.46 [P < .001]) and PFS (hazard ratio, 0.38; 95% CI, 0.20-0.72 [P = .003]) compared with patients at intermediate risk (those with an SFI <73 and IFI <3.4) and poor risk (those with an SFI <73 and IFI ≥3.4). The Uno concordance statistics were found to be higher for fat risk groups than BMI in predicting OS (0.603 vs 0.574; P = .581) and PFS (0.602 vs 0.586; P = .71). CONCLUSIONS: Increased BMI, increased SFI, and decreased IFI may be associated with prolonged survival in patients with cancer who are treated with immunotherapy. Further studies are needed to elucidate the effect of adiposity on the host immune response to immunotherapy.

Phase 1 safety and pharmacodynamic study of lenalidomide combined with everolimus in patients with advanced solid malignancies with efficacy signal in adenoid cystic carcinoma.

BACKGROUND: Purpose: The combination of a mammalian target of rapamycin inhibitor and lenalidomide showed enhanced preclinical cytotoxicity. We conducted a phase 1 study in advanced solid tumour patients to assess safety, efficacy and pharmacodynamic (PD) outcomes. METHODS: We employed a 3+3 dose escalation design to establish the safety and recommended phase 2 doses (RP2D) of daily everolimus and lenalidomide in patients with advanced solid tumours. The starting doses were 5 and 10 mg, respectively, with planned escalation to maximum single-agent doses of 10 and 25 mg in the absence of dose-limiting toxicity. PD endpoints of lymphocyte subsets and immune cytokines were assessed in peripheral blood using multiparameter flow cytometry and LUMINEX assay. Efficacy was evaluated by cross-sectional imaging after every two cycles of treatment. RESULTS: The study enrolled 44 patients, median age of 58 years and 28 males (63.6%). The RP2D was established as 10 and 25 mg daily continuously for everolimus and lenalidomide. Common (>5%) grade ≥3 adverse events included rash (19%), neutropenia (19%), hypokalaemia (11%) and fatigue (9%). Best efficacy outcomes in 36 evaluable patients were partial response in 5 (13.8%), stable disease in 24 (55.8%) and progressive disease in 7 (19.4%) patients. PD assessment revealed significant association of cytokine levels (interleukin-2 (IL2), IL21 and IL17), baseline activated and total CD8+ lymphocytes and change in B cell lymphocytes and activated NK cells with clinical benefit. CONCLUSIONS: The study demonstrated the safety of everolimus and lenalidomide with promising efficacy signal in thyroid and adenoid cystic cancers. CLINICAL TRIAL REGISTRATION: NCT01218555.