Society for Immunotherapy of Cancer (SITC) recommendations on intratumoral immunotherapy clinical trials (IICT): from premalignant to metastatic disease.

BACKGROUND: Intratumorally delivered immunotherapies have the potential to favorably alter the local tumor microenvironment and may stimulate systemic host immunity, offering an alternative or adjunct to other local and systemic treatments. Despite their potential, these therapies have had limited success in late-phase trials for advanced cancer resulting in few formal approvals. The Society for Immunotherapy of Cancer (SITC) convened a panel of experts to determine how to design clinical trials with the greatest chance of demonstrating the benefits of intratumoral immunotherapy for patients with cancers across all stages of pathogenesis. METHODS: An Intratumoral Immunotherapy Clinical Trials Expert Panel composed of international key stakeholders from academia and industry was assembled. A multiple choice/free response survey was distributed to the panel, and the results of this survey were discussed during a half-day consensus meeting. Key discussion points are summarized in the following manuscript. RESULTS: The panel determined unique clinical trial designs tailored to different stages of cancer development-from premalignant to unresectable/metastatic-that can maximize the chance of capturing the effect of intratumoral immunotherapies. Design elements discussed included study type, patient stratification and exclusion criteria, indications of randomization, study arm determination, endpoints, biological sample collection, and response assessment with biomarkers and imaging. Populations to prioritize for the study of intratumoral immunotherapy, including stage, type of cancer and line of treatment, were also discussed along with common barriers to the development of these local treatments. CONCLUSIONS: The SITC Intratumoral Immunotherapy Clinical Trials Expert Panel has identified key considerations for the design and implementation of studies that have the greatest potential to capture the effect of intratumorally delivered immunotherapies. With more effective and standardized trial designs, the potential of intratumoral immunotherapy can be realized and lead to regulatory approvals that will extend the benefit of these local treatments to the patients who need them the most.

Immune Checkpoint Inhibitor-Induced Myositis/Myasthenia Gravis Overlap.

Immune checkpoint inhibitors (ICIs) have considerably changed the management of several malignancies. Although these agents transformed the scope of management in oncology and proved long-term efficacy, they have been associated with numerous autoimmune-related adverse events. We presented a case of a 61-year-old male with a history of non-small cell lung cancer (NSCLC) who presented with respiratory failure requiring mechanical ventilation. He was discharged with a working diagnosis of myasthenia gravis crisis secondary to the use of pembrolizumab. On further evaluation, he was found to possibly have pembrolizumab-induced myositis. He was treated with plasmapheresis, methylprednisolone, and rituximab and achieved significant improvement. Pembrolizumab, a monoclonal antibody, is an ICI that targets programmed death protein 1 (PD-1), thereby blocking the interaction between PD-1 and PDL-1, leading to an enhancement of T-cell mediated immune response against tumor cells. Pembrolizumab has been used to treat a variety of malignancies including melanoma, NSCLC, and other solid tumors. Though ICIs have revolutionized the field of oncology, they should be used with caution. ICIs can cause immune-related adverse events (irAEs), including myasthenia gravis and myositis. Diagnosing irAEs is challenging due to their nonspecific presentations and lack of antibody markers. Therefore, patients and clinicians should be aware of irAEs in order to initiate timely intervention.

Cellular Therapy for Lung Cancer: Focusing on Chimeric Antigen Receptor T (CAR T) Cells and Tumor-Infiltrating Lymphocyte (TIL) Therapy.

Lung cancer is a leading cause of morbidity and mortality in the United States and worldwide. The introduction of immune checkpoint inhibitors has led to a marked improvement in the outcomes of lung cancer patients. Despite these advances, there is a huge unmet need for therapeutic options in patients who are not candidates for targeted or immunotherapy or those who progress after first-line treatment. With its high mutational burden, lung cancer appears to be an attractive target for novel personalized treatment approaches. In this review, we provide an overview of two adoptive cell therapy approaches-chimeric antigen receptors (CAR) T-cell therapy and Tumor-infiltrating lymphocytes (TILs) in lung cancer with an emphasis on current challenges and future perspectives. While both these therapies are still in the early phases of development in lung cancer and need more refinement, they harbor the potential to be effective treatment options for this group of patients with otherwise poor prognoses.

Plasma Thermogram Parameters Differentiate Status and Overall Survival of Melanoma Patients.

Melanoma is the fifth most common cancer in the United States and the deadliest of all skin cancers. Even with recent advancements in treatment, there is still a 13% two-year recurrence rate, with approximately 30% of recurrences being distant metastases. Identifying patients at high risk for recurrence or advanced disease is critical for optimal clinical decision-making. Currently, there is substantial variability in the selection of screening tests and imaging, with most modalities characterized by relatively low accuracy. In the current study, we built upon a preliminary examination of differential scanning calorimetry (DSC) in the melanoma setting to examine its utility for diagnostic and prognostic assessment. Using regression analysis, we found that selected DSC profile (thermogram) parameters were useful for differentiation between melanoma patients and healthy controls, with more complex models distinguishing melanoma patients with no evidence of disease from patients with active disease. Thermogram features contributing to the third principal component (PC3) were useful for differentiation between controls and melanoma patients, and Cox proportional hazards regression analysis indicated that PC3 was useful for predicting the overall survival of active melanoma patients. With the further development and optimization of the classification method, DSC could complement current diagnostic strategies to improve screening, diagnosis, and prognosis of melanoma patients.

Monocytic MDSCs exhibit superior immune suppression via adenosine and depletion of adenosine improves efficacy of immunotherapy.

Immune checkpoint inhibitor (ICI) therapy is effective against many cancers for a subset of patients; a large percentage of patients remain unresponsive to this therapy. One contributing factor to ICI resistance is accumulation of monocytic myeloid-derived suppressor cells (M-MDSCs), a subset of innate immune cells with potent immunosuppressive activity against T lymphocytes. Here, using lung, melanoma, and breast cancer mouse models, we show that CD73-expressing M-MDSCs in the tumor microenvironment (TME) exhibit superior T cell suppressor function. Tumor-derived PGE2, a prostaglandin, directly induces CD73 expression in M-MDSCs via both Stat3 and CREB. The resulting CD73 overexpression induces elevated levels of adenosine, a nucleoside with T cell-suppressive activity, culminating in suppression of antitumor CD8+ T cell activity. Depletion of adenosine in the TME by the repurposed drug PEGylated adenosine deaminase (PEG-ADA) increases CD8+ T cell activity and enhances response to ICI therapy. Use of PEG-ADA can therefore be a therapeutic option to overcome resistance to ICIs in cancer patients.

Talimogene laherparepvec in combination with ipilimumab versus ipilimumab alone for advanced melanoma: 5-year final analysis of a multicenter, randomized, open-label, phase II trial.

Talimogene laherparepvec (T-VEC) plus ipilimumab has demonstrated greater antitumor activity versus ipilimumab alone, without additional toxicity, in patients with advanced melanoma. Here, we report the 5-year outcomes from a randomized phase II study. These data provide the longest efficacy and safety follow-up for patients with melanoma treated with a combination of an oncolytic virus and a checkpoint inhibitor.Eligible patients with unresectable stage IIIB‒IV melanoma were randomized 1:1 to receive T-VEC plus ipilimumab or ipilimumab alone. T-VEC was administered intralesionally at 106 plaque-forming units (PFU)/mL in week 1, followed by 108 PFU/mL in week 4 and every 2 weeks thereafter. Ipilimumab (3 mg/kg every 3 weeks; ≤4 doses) was administered intravenously starting at week 1 in the ipilimumab arm and week 6 in the combination arm. The primary end point was investigator-assessed objective response rate (ORR) per immune-related response criteria; key secondary end points included durable response rate (DRR), duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety.Overall, 198 patients were randomized to receive the combination (n=98) or ipilimumab (n=100). The combination improved the ORR versus ipilimumab (35.7% vs 16.0%; OR 2.9; 95% CI 1.5 to 5.7; p=0.003). DRR was 33.7% and 13.0% (unadjusted OR 3.4; 95% CI 1.7 to 7.0; descriptive p=0.001), respectively. Among the objective responders, the median DOR was 69.2 months (95% CI 38.5 to not estimable) with the combination and was not reached with ipilimumab. Median PFS was 13.5 months with the combination and 6.4 months with ipilimumab (HR 0.78; 95% CI 0.55 to 1.09; descriptive p=0.14). Estimated 5-year OS was 54.7% (95% CI 43.9 to 64.2) in the combination arm and 48.4% (95% CI 37.9 to 58.1) in the ipilimumab arm. Forty-seven (48.0%) and 65 (65.0%) patients in the combination and ipilimumab arms, respectively, received subsequent therapies. No new safety signals were reported.At the 5-year follow-up, the improved response rates observed with T-VEC plus ipilimumab were durable. This is the first randomized controlled study of the combination of an oncolytic virus and a checkpoint inhibitor that meets its primary end point.Trial registration number: NCT01740297.

Optimizing Reversal of Muscle Relaxation with Sugammadex to Accelerate Discharge Readiness in Operative Laryngoscopy: A Randomized Clinical Trial.

IMPORTANCE: Operative laryngoscopy is a commonly performed ambulatory procedure in patients with significant co-morbidity. Optimal anesthetics for surgical exposure with rapid return to baseline after the procedure enhances postoperative patient safety. OBJECTIVE: To determine whether sugammadex hastens recovery in patients undergoing operative laryngoscopy under general anesthesia with rocuronium-induced paralysis. DESIGN: Prospective clinical intervention randomized single-blinded, single-center study in an academic tertiary care center. Approved by the institutional review board and registered with ClinicalTrials.gov. SETTINGS: Single center tertiary care academic institution. PARTICIPANTS: 18 years or older, American Society of Anesthesiology physical status I-III with ability to give written informed consent undergoing operative laryngoscopy. INTERVENTION: Participants were randomized into two groups. Both groups received inhaled anesthetic: sevoflurane, remifentanil, and rocuronium at 0.6-1.2 mg/kg for intubation and anti-nausea prophylaxis. Group 1 received reversal with neostigmine (0.04 mg/kg) and glycopyrrolate (0.01 mg/kg). Group 2 received reversal with sugammadex (4 mg/kg). Vital signs were maintained at 20% of baseline in both groups. Post anesthesia care unit nurses were blinded to the reversal agent and were the evaluators of the discharge criteria and times. Primary end point was time to extubation after the procedures and secondary end points were: Subjective interpretation of surgical conditions by the surgeon, hemodynamic, respiratory parameters, anesthetics, and opioids used, operative time, and duration to achieve discharge readiness. RESULTS: A total of eighty-four participants, who were similar in age, sex, and weight in both groups. The primary end point and secondary end points were similar except time to meet discharge criteria in the two groups. 65% in the sugammadex versus 35% in the neostigmine group met Aldrete criteria of 18 or higher on arrival at the post anesthesia care unit. CONCLUSIONS: Optimizing the anesthetic regimen, along with stable intraoperative hemodynamics and reversal with sugammadex improves discharge readiness in patients undergoing operative laryngoscopy.

Randomized, Double-Blind, Placebo-Controlled, Global Phase III Trial of Talimogene Laherparepvec Combined With Pembrolizumab for Advanced Melanoma.

PURPOSE: The combination of talimogene laherparepvec (T-VEC) and pembrolizumab previously demonstrated an acceptable safety profile and an encouraging complete response rate (CRR) in patients with advanced melanoma in a phase Ib study. We report the efficacy and safety from a phase III, randomized, double-blind, multicenter, international study of T-VEC plus pembrolizumab (T-VEC-pembrolizumab) versus placebo plus pembrolizumab (placebo-pembrolizumab) in patients with advanced melanoma. METHODS: Patients with stage IIIB-IVM1c unresectable melanoma, naïve to antiprogrammed cell death protein-1, were randomly assigned 1:1 to T-VEC-pembrolizumab or placebo-pembrolizumab. T-VEC was administered at ≤ 4 × 106 plaque-forming unit (PFU) followed by ≤ 4 × 108 PFU 3 weeks later and once every 2 weeks until dose 5 and once every 3 weeks thereafter. Pembrolizumab was administered intravenously 200 mg once every 3 weeks. The dual primary end points were progression-free survival (PFS) per modified RECIST 1.1 by blinded independent central review and overall survival (OS). Secondary end points included objective response rate per mRECIST, CRR, and safety. Here, we report the primary analysis for PFS, the second preplanned interim analysis for OS, and the final analysis. RESULTS: Overall, 692 patients were randomly assigned (346 T-VEC-pembrolizumab and 346 placebo-pembrolizumab). T-VEC-pembrolizumab did not significantly improve PFS (hazard ratio, 0.86; 95% CI, 0.71 to 1.04; P = .13) or OS (hazard ratio, 0.96; 95% CI, 0.76 to 1.22; P = .74) compared with placebo-pembrolizumab. The objective response rate was 48.6% for T-VEC-pembrolizumab (CRR 17.9%) and 41.3% for placebo-pembrolizumab (CRR 11.6%); the durable response rate was 42.2% and 34.1% for the arms, respectively. Grade ≥ 3 treatment-related adverse events occurred in 20.7% of patients in the T-VEC-pembrolizumab arm and in 19.5% of patients in the placebo-pembrolizumab arm. CONCLUSION: T-VEC-pembrolizumab did not significantly improve PFS or OS compared with placebo-pembrolizumab. Safety results of the T-VEC-pembrolizumab combination were consistent with the safety profiles of each agent alone.

Lung cancer metabolomic data from tumor core biopsies enables risk-score calculation for progression-free and overall survival.

INTRODUCTION: Metabolomics has emerged as a powerful method to provide insight into cancer progression, including separating patients into low- and high-risk groups for overall (OS) and progression-free survival (PFS). However, survival prediction based mainly on metabolites obtained from biofluids remains elusive. OBJECTIVES: This proof-of-concept study evaluates metabolites as biomarkers obtained directly from tumor core biopsies along with covariates age, sex, pathological stage at diagnosis (I/II vs. III/VI), histological subtype, and treatment vs. no treatment to risk stratify lung cancer patients in terms of OS and PFS. METHODS: Tumor core biopsy samples obtained during routine lung cancer patient care at the University of Louisville Hospital and Norton Hospital were evaluated with high-resolution 2DLC-MS/MS, and the data were analyzed by Kaplan-Meier survival analysis and Cox proportional hazards regression. A linear equation was developed to stratify patients into low and high risk groups based on log-transformed intensities of key metabolites. Sparse partial least squares discriminant analysis (SPLS-DA) was performed to predict OS and PFS events. RESULTS: Univariable Cox proportional hazards regression model coefficients divided by the standard errors were used as weight coefficients multiplied by log-transformed metabolite intensity, then summed to generate a risk score for each patient. Risk scores based on 10 metabolites for OS and 5 metabolites for PFS were significant predictors of survival. Risk scores were validated with SPLS-DA classification model (AUROC 0.868 for OS and AUROC 0.755 for PFS, when combined with covariates). CONCLUSION: Metabolomic analysis of lung tumor core biopsies has the potential to differentiate patients into low- and high-risk groups based on OS and PFS events and probability.

Single-Cell Immune Mapping of Melanoma Sentinel Lymph Nodes Reveals an Actionable Immunotolerant Microenvironment.

PURPOSE: Improving our understanding of the immunologic response to cancer cells within the sentinel lymph nodes (SLN) of primary tumors is expected to identify new approaches to stimulate clinically meaningful cancer immunity. EXPERIMENTAL DESIGN: We used mass cytometry by time-of-flight (CyTOF), flow cytometry, and T-cell receptor immunosequencing to conduct simultaneous single-cell analyses of immune cells in the SLNs of patients with melanoma. RESULTS: We found increased effector-memory αß T cells, TCR clonality, and γδ T cells selectively in the melanoma-bearing SLNs relative to non-melanoma-bearing SLNs, consistent with possible activation of an antitumor immune response. However, we also observed a markedly immunotolerant environment in the melanoma-bearing SLNs indicated by reduced and impaired NK cells and increased levels of CD8+CD57+PD-1+ cells, which are known to display low melanoma killing capabilities. Other changes observed in melanoma-bearing SLNs when compared with non-melanoma-bearing SLNs include (i) reduced CD8+CD69+ T cell/T regulatory cell ratio, (ii) high PD-1 expression on CD4+ and CD8+ T cells, and (iii) high CTLA-4 expression on γδ T cells. CONCLUSIONS: Our data suggest that these immunologic changes compromise antimelanoma immunity and contribute to a high relapse rate. We propose the development of clinical trials to test the neo-adjuvant administration of anti-PD-1 antibodies prior to SLN resection in patients with stage III melanoma. See related commentary by Lund, p. 1996.

Efficacy and safety of lifileucel, a one-time autologous tumor-infiltrating lymphocyte (TIL) cell therapy, in patients with advanced melanoma after progression on immune checkpoint inhibitors and targeted therapies: pooled analysis of consecutive cohorts of the C-144-01 study.

BACKGROUND: Patients with advanced melanoma have limited treatment options after progression on immune checkpoint inhibitors (ICI). Lifileucel, a one-time autologous tumor-infiltrating lymphocyte (TIL) cell therapy, demonstrated an investigator-assessed objective response rate (ORR) of 36% in 66 patients who progressed after ICI and targeted therapy. Herein, we report independent review committee (IRC)-assessed outcomes of 153 patients treated with lifileucel in a large multicenter Phase 2 cell therapy trial in melanoma. METHODS: Eligible patients had advanced melanoma that progressed after ICI and targeted therapy, where appropriate. Melanoma lesions were resected (resected tumor diameter ≥1.5 cm) and shipped to a central good manufacturing practice facility for 22-day lifileucel manufacturing. Patients received a non-myeloablative lymphodepletion regimen, a single lifileucel infusion, and up to six doses of high-dose interleukin-2. The primary endpoint was IRC-assessed ORR (Response Evaluation Criteria in Solid Tumors V.1.1). RESULTS: The Full Analysis Set consisted of 153 patients treated with lifileucel, including longer-term follow-up on the 66 patients previously reported. Patients had received a median of 3.0 lines of prior therapy (81.7% received both anti-programmed cell death protein 1 and anti-cytotoxic lymphocyte-associated protein 4) and had high disease burden at baseline (median target lesion sum of diameters (SOD): 97.8 mm; lactate dehydrogenase (LDH) >upper limit of normal: 54.2%). ORR was 31.4% (95% CI: 24.1% to 39.4%), with 8 complete responses and 40 partial responses. Median duration of response was not reached at a median study follow-up of 27.6 months, with 41.7% of the responses maintained for ≥18 months. Median overall survival and progression-free survival were 13.9 and 4.1 months, respectively. Multivariable analyses adjusted for Eastern Cooperative Oncology Group performance status demonstrated that elevated LDH and target lesion SOD >median were independently correlated with ORR (p=0.008); patients with normal LDH and SOD

PFKFB3 Inhibition Impairs Erlotinib-Induced Autophagy in NSCLCs.

Tyrosine kinase inhibitors (TKIs) targeting the kinase domain of the epidermal growth factor receptor (EGFR), such as erlotinib, have dramatically improved clinical outcomes of patients with EGFR-driven non-small cell lung carcinomas (NSCLCs). However, intrinsic or acquired resistance remains a clinical barrier to the success of FDA-approved EGFR TKIs. Multiple mechanisms of resistance have been identified, including the activation of prosurvival autophagy. We have previously shown that the expression and activity of PFKFB3-a known driver of glycolysis-is associated with resistance to erlotinib and that PFKFB3 inhibition improves the response of NSCLC cells to erlotinib. This study focuses on investigating the role of PFKFB3 in regulating erlotinib-driven autophagy to escape resistance to erlotinib. We evaluated the consequence of pharmacological inhibition of PFKFB3 on erlotinib-driven autophagy in NSCLC cells with different mutation statuses. Here, we identify PFKFB3 as a mediator of erlotinib-induced autophagy in NSCLCs. We demonstrate that PFKFB3 inhibition sensitizes NCSLCs to erlotinib via impairing autophagy flux. In summary, our studies uncovered a novel crosstalk between PFKFB3 and EGFR that regulates erlotinib-induced autophagy, thus contributing to erlotinib sensitivity in NSCLCs.

Longitudinal Relationship between Idylla Plasma ctBRAF V600 Mutation Detection and Tumor Burden in Patients with Metastatic Melanoma.

BACKGROUND: Circulating tumor DNA (ctDNA) may complement radiography for interim assessment of patients with cancer. OBJECTIVE: Our objective was to explore the relationship between changes in plasma ctDNA versus radiographic imaging among patients with metastatic melanoma. METHODS: Using the Idylla system, we measured B-Raf proto-oncogene (BRAF) V600 ctDNA in plasma from 15 patients with BRAF V600E/K-positive primary tumors undergoing standard-of-care monitoring, including cross-sectional computed tomography (CT) imaging. BRAF V600 mutant allele frequency (%MAF) was calculated from the Idylla Cq values and directly measured using droplet digital polymerase chain reaction (ddPCR). RESULTS: The Idylla ctDNA assay demonstrated 91% sensitivity, 96% specificity, 91% positive predictive value, and 96% negative predictive value for the presence of > 93 mm metastatic disease. Qualitative ctDNA results corresponded to changes in RECIST (Response Evaluation Criteria in Solid Tumors) 1.1 status determined by CT imaging in 11 of 15 subjects (73%). Calculated %MAF results correlated with ddPCR (R2 = 0.94) and provided evidence of progressive disease 55 and 97 days in advance of CT imaging for two subjects with persistently positive qualitative results. CONCLUSIONS: Overall, interim ctDNA results provided evidence of partial response or progressive disease an average of 82 days before radiography. This pilot study supports the feasibility of using the Idylla plasma BRAF V600 ctDNA assay as a complement to CT scanning for routine monitoring of therapeutic response. Somatic mutation quantification based on Cq values shows promise for identifying disease progression and warrants further validation.

Lifileucel, a Tumor-Infiltrating Lymphocyte Therapy, in Metastatic Melanoma.

PURPOSE: Effective treatment options are limited for patients with advanced (metastatic or unresectable) melanoma who progress after immune checkpoint inhibitors and targeted therapies. Adoptive cell therapy using tumor-infiltrating lymphocytes has demonstrated efficacy in advanced melanoma. Lifileucel is an autologous, centrally manufactured tumor-infiltrating lymphocyte product. METHODS: We conducted a phase II open-label, single-arm, multicenter study in patients with advanced melanoma who had been previously treated with checkpoint inhibitor(s) and BRAF ± MEK targeted agents. Lifileucel was produced from harvested tumor specimens in central Good Manufacturing Practice facilities using a streamlined 22-day process. Patients received a nonmyeloablative lymphodepletion regimen, a single infusion of lifileucel, and up to six doses of high-dose interleukin-2. The primary end point was investigator-assessed objective response rate (ORR) per RECIST, version 1.1. RESULTS: Sixty-six patients received a mean of 3.3 prior therapies (anti-programmed death 1 [PD-1] or programmed death ligand 1 [PD-L1]: 100%; anticytotoxic T-lymphocyte-associated protein-4: 80%; BRAF ± MEK inhibitor: 23%). The ORR was 36% (95% CI, 25 to 49), with two complete responses and 22 partial responses. Disease control rate was 80% (95% CI, 69 to 89). Median duration of response was not reached after 18.7-month median study follow-up (range, 0.2-34.1 months). In the primary refractory to anti-PD-1 or PD-L1 therapy subset, the ORR and disease control rate were 41% (95% CI, 26 to 57) and 81% (95% CI, 66 to 91), respectively. Safety profile was consistent with known adverse events associated with nonmyeloablative lymphodepletion and interleukin-2. CONCLUSION: Lifileucel demonstrated durable responses and addresses a major unmet need in patients with metastatic melanoma with limited treatment options after approved therapy, including the primary refractory to anti-PD-1 or PD-L1 therapy subset.

Differential gene expression analysis of palbociclib-resistant TNBC via RNA-seq.

PURPOSE: The management of triple-negative breast cancer (TNBC) remains a significant clinical challenge due to the lack of effective targeted therapies. Inhibitors of the cyclin-dependent kinases 4 and 6 (CDK4/6) are emerging as promising therapeutic agents against TNBC; however, cells can rapidly acquire resistance through multiple mechanisms that are yet to be identified. Therefore, determining the mechanisms underlying resistance to CDK4/6 inhibition is crucial to develop combination therapies that can extend the efficacy of the CDK4/6 inhibitors or delay resistance. This study aims to identify differentially expressed genes (DEG) associated with acquired resistance to palbociclib in ER- breast cancer cells. METHODS: We performed next-generation transcriptomic sequencing (RNA-seq) and pathway analysis in ER- MDA-MB-231 palbociclib-sensitive (231/pS) and palbociclib-resistant (231/pR) cells. RESULTS: We identified 2247 up-regulated and 1427 down-regulated transcripts in 231/pR compared to 231/pS cells. DEGs were subjected to functional analysis using Gene Ontology (GO) and the KEGG database which identified many transduction pathways associated with breast cancer, including the PI3K/AKT, PTEN and mTOR pathways. Additionally, Ingenuity Pathway Analysis (IPA) revealed that resistance to palbociclib is closely associated with altered cholesterol and fatty acid biosynthesis suggesting that resistance to palbociclib may be dependent on lipid metabolic reprograming. CONCLUSION: This study provides evidence that lipid metabolism is altered in TNBC with acquired resistance to palbociclib. Further studies are needed to determine if the observed lipid metabolic rewiring can be exploited to overcome therapy resistance in TNBC.

Talimogene Laherparepvec and Pembrolizumab in Recurrent or Metastatic Squamous Cell Carcinoma of the Head and Neck (MASTERKEY-232): A Multicenter, Phase 1b Study.

PURPOSE: The prognosis for patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) is poor, and only a minority of patients benefit from checkpoint immunotherapy. Talimogene laherparepvec (T-VEC), an oncolytic immunotherapy approved for advanced melanoma, in combination with pembrolizumab may yield enhanced antitumor activity over either agent alone. PATIENTS AND METHODS: This was a phase Ib/III, multicenter trial testing intratumoral T-VEC combined with intravenous pembrolizumab in R/M HNSCC refractory to platinum-based chemotherapy. For phase Ib, primary endpoint was incidence of dose-limiting toxicity (DLT). Key secondary endpoints included objective response rate and progression-free survival per irRECIST, overall survival, and safety. RESULTS: Thirty-six patients were enrolled into the phase Ib study. The data cut-off date was August 28, 2018. Median follow-up was 5.8 months (range, 0.3-24.2). One DLT of T-VEC-related fatal arterial hemorrhage was reported. Twenty (55.6%) and 21 (58.3%) patients experienced adverse events (AE) related to T-VEC and pembrolizumab, respectively. Besides the DLT, there were no treatment-related fatal AEs. A confirmed partial response was observed in 5 (13.9%) patients. Ten (27.8%) patients were unevaluable for response due to early death. Median PFS and OS were 3.0 months [95% confidence interval (Cl), 2.0-5.8] and 5.8 months (95% Cl, 2.9-11.4), respectively. CONCLUSIONS: The combination of T-VEC and pembrolizumab demonstrated a tolerable safety profile in R/M HNSCC. The efficacy with the combination was similar to that with pembrolizumab monotherapy in historical HNSCC studies. Phase III part of this study was not further pursued (ClinicalTrials.gov Identifier: NCT02626000).

PFKFB2 regulates glycolysis and proliferation in pancreatic cancer cells.

Tumor cells increase glucose metabolism through glycolysis and pentose phosphate pathways to meet the bioenergetic and biosynthetic demands of rapid cell proliferation. The family of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases (PFKFB1-4) are key regulators of glucose metabolism via their synthesis of fructose-2,6-bisphosphate (F2,6BP), a potent activator of glycolysis. Previous studies have reported the co-expression of PFKFB isozymes, as well as the mRNA splice variants of particular PFKFB isozymes, suggesting non-redundant functions. Majority of the evidence demonstrating a requirement for PFKFB activity in increased glycolysis and oncogenic properties in tumor cells comes from studies on PFKFB3 and PFKFB4 isozymes. In this study, we show that the PFKFB2 isozyme is expressed in tumor cell lines of various origin, overexpressed and localizes to the nucleus in pancreatic adenocarcinoma, relative to normal pancreatic tissue. We then demonstrate the differential intracellular localization of two PFKFB2 mRNA splice variants and that, when ectopically expressed, cytoplasmically localized mRNA splice variant causes a greater increase in F2,6BP which coincides with an increased glucose uptake, as compared with the mRNA splice variant localizing to the nucleus. We then show that PFKFB2 expression is required for steady-state F2,6BP levels, glycolytic activity, and proliferation of pancreatic adenocarcinoma cells. In conclusion, this study may provide a rationale for detailed investigation of PFKFB2's requirement for the glycolytic and oncogenic phenotype of pancreatic adenocarcinoma cells.