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result(s) for
"Pike, Luke"
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Safety of combining radiotherapy with immune-checkpoint inhibition
by
Hwang, William L
,
Loeffler, Jay S
,
Mahal, Brandon A
in
Antigen presentation
,
Antigen-presenting cells
,
Antigens
2018
Immune-checkpoint inhibitors targeting cytotoxic T- lymphocyte antigen 4 (CTLA-4), programmed cell death protein 1 (PD-1), or programmed cell death 1 ligand 1 (PD-L1) have transformed the care of patients with a wide range of advanced-stage malignancies. More than half of these patients will also have an indication for treatment with radiotherapy. The effects of both radiotherapy and immune-checkpoint inhibition (ICI) involve a complex interplay with the innate and adaptive immune systems, and accumulating evidence suggests that, under certain circumstances, the effects of radiotherapy synergize with those of ICI to augment the antitumour responses typically observed with either modality alone and thus improve clinical outcomes. However, the mechanisms by which radiotherapy and immune-checkpoint inhibitors synergistically modulate the immune response might also affect both the type and severity of treatment-related toxicities. Moreover, in patients receiving immune-checkpoint inhibitors, the development of immune-related adverse events has been linked with superior treatment responses and patient survival durations, suggesting a relationship between the antitumour and adverse autoimmune effects of these agents. In this Review, we discuss the emerging data on toxicity profiles related to immune-checkpoint inhibitors and radiotherapy, both separately and in combination, their potential mechanisms, and the approaches to managing these toxicities.
Journal Article
Genomic analysis and clinical correlations of non-small cell lung cancer brain metastasis
by
Reis-Filho, Jorge S.
,
Schultz, Nikolaus
,
Tringale, Kathryn R.
in
45/23
,
631/67/1612/1350
,
631/67/322
2023
Up to 50% of patients with non-small cell lung cancer (NSCLC) develop brain metastasis (BM), yet the study of BM genomics has been limited by tissue access, incomplete clinical data, and a lack of comparison with paired extracranial specimens. Here we report a cohort of 233 patients with resected and sequenced (MSK-IMPACT) NSCLC BM and comprehensive clinical data. With matched samples (47 primary tumor, 42 extracranial metastatic), we show
CDKN2A/B
deletions and cell cycle pathway alterations to be enriched in the BM samples. Meaningful clinico-genomic correlations are noted, namely
EGFR
alterations in leptomeningeal disease (LMD) and
MYC
amplifications in multifocal regional brain progression. Patients who developed early LMD frequently have had uncommon, multiple, and persistently detectable
EGFR
driver mutations. The distinct mutational patterns identified in BM specimens compared to other tissue sites suggest specific biologic underpinnings of intracranial progression.
The genomic landscape of brain metastasis (BM) in patients with non-small cell lung cancer (NSCLC) remains to be explored. Here, the authors analyse a cohort of 233 patients with BM including 47 primary tumour, 42 extracranial metastatic matched samples and reveal distinct mutational patterns.
Journal Article
Advances in the Management of Lung Cancer Brain Metastases
by
Hockemeyer, Kathryn G.
,
Rusthoven, Chad G.
,
Pike, Luke R. G.
in
Brain cancer
,
Brain injury
,
Cancer
2024
Lung cancer, both non-small cell and small cell, harbors a high propensity for spreading to the central nervous system. Radiation therapy remains the backbone of the management of brain metastases. Recent advances in stereotactic radiosurgery have expanded its indications and ongoing studies seek to elucidate optimal fractionation and coordination with systemic therapies, especially targeted inhibitors with intracranial efficacy. Efforts in whole-brain radiotherapy aim to preserve neurocognition and to investigate the need for prophylactic cranial irradiation. As novel combinatorial strategies are tested and prognostic/predictive biomarkers are identified and tested, the management of brain metastases in lung cancer will become increasingly personalized to optimally balance intracranial efficacy with preserving neurocognitive function and patient values.
Journal Article
Recent Advances and Applications of Radiation Therapy for Brain Metastases
2022
Purpose of ReviewRadiation therapy (RT) is a mainstay of treatment for brain metastases from solid tumors. Treatment of these patients is complex and should focus on minimizing symptoms, preserving functional status, and prolonging survival.Recent FindingsWhole-brain radiotherapy (WBRT) can lead to toxicity, and while it does reduce recurrence in the CNS, this has not been shown to provide a survival benefit. Recent advances focus on reducing the toxicity of WBRT or using more targeted radiation therapy. New paradigms including the use of proton RT for leptomeningeal metastases (LM) and stereotactic radiosurgery (SRS) before craniotomy hold promise in improving treatment efficacy and reducing toxicity.SummaryOmission or replacement of WBRT is often safe and the use of SRS is expanding to include patients with more lesions and preoperative RT. Proton RT holds promise for LM. Progress is being made in improving patient-centered outcomes and reducing toxicity for patients with brain metastases.
Journal Article
Clinical experience with a same‐day simulation and treatment program for stereotactic radiation therapy on a C‐arm linac
by
Cervino, Laura
,
Shen, Sernger
,
Pike, Luke R. G.
in
Aged
,
Application programming interface
,
Brain Neoplasms - radiotherapy
2026
Purpose We report our experience with the implementation of a same‐day simulation and treatment C‐arm linear accelerator (linac)‐based stereotactic program for patients with intracranial and extracranial metastatic disease. Methods Between May 2021 and October 2023, patients were treated in our same‐day program with linac‐based SRS/SBRT. Two slots per week were offered. Patients with expedited clinical needs, able to undergo SRS/SBRT simulation and treatment, were considered. Extracranial treatments were required to meet standards for automated intensity modulated radiation therapy (IMRT) optimization. Intracranial treatments were limited to 1–3 lesions and 1–2 isocenters. The day before treatment, the patient needed to be identified, and any diagnostic imaging had to be available for the physician and dosimetrist to discuss the plan. On the day of treatment, simulation was scheduled for 8 AM and treatment at 4 PM by default, with the goal to complete treatment by 6 PM. We analyzed information about each patient's treatment plan and time spent on each step of the workflow. Results Ninety‐seven patients followed our same‐day workflow and were included in the analysis. Seventy‐five patients received intracranial SRS (57% to 1 lesion), while 22 patients received extracranial treatments (50% to the extremities). Simulation often required additional time to be completed, finishing a median 18 min (IQR 5–40) after the goal end time. The median time between simulation completion and end of the same‐day treatment was 7.8 h (IQR 7.4–8.6). Treatment technique and the number of target volumes had a significant impact on planning time. The median treatment end time was 5:13 PM (IQR 4:46 PM–6:01 PM), with 74% ending by 6 PM. Conclusions A linac‐based program to treat patients with SRS/SBRT in an expedited fashion was established and successfully treated patients in a same‐day timeline. Careful selection of planning techniques to limit plan complexity and adding automation in time‐consuming parts of the process are crucial when developing expedited workflows.
Journal Article
ATF4 orchestrates a program of BH3-only protein expression in severe hypoxia
by
Phadwal, Kanchan
,
Harris, Adrian L.
,
Simon, Anna Katharina
in
Activating Transcription Factor 4 - metabolism
,
Animal Anatomy
,
Animal Biochemistry
2012
Intratumoral hypoxia is associated with poor prognosis, regardless of the mode of therapy. Cancer cells survive this condition through activating several adaptive signaling pathways, including the integrated stress response (ISR) and autophagy. Activating transcription factor 4 (ATF4) is the major transcriptional mediator of the ISR, which we have shown to be involved in autophagy regulation to protect cells from severe hypoxia. Here we demonstrate that ATF4 orchestrates a program of BH3-only protein expression in severe hypoxia. We find that the BH3-only proteins HRK, PUMA, and NOXA are transcriptionally induced in severe hypoxia and that their expression is abrogated by RNA interference against ATF4. In particular, we show that the BH3-only protein harakiri (HRK) is transactivated by ATF4 in severe hypoxia through direct binding of ATF4 to the promoter region. Furthermore, we demonstrate through siRNA knockdown that HRK induces autophagy and promotes cancer cell survival in severe hypoxia.
Journal Article
Fast, light, and scalable: harnessing data-mined line annotations for automated tumor segmentation on brain MRI
by
Panyam, Prashanth Kumar
,
Shih, Hao-Hsin
,
Murthy, Krishna Nand Keshava
in
Adult
,
Annotations
,
Automation
2023
Objectives
While fully supervised learning can yield high-performing segmentation models, the effort required to manually segment large training sets limits practical utility. We investigate whether data mined line annotations can facilitate brain MRI tumor segmentation model development without requiring manually segmented training data.
Methods
In this retrospective study, a tumor detection model trained using clinical line annotations mined from PACS was leveraged with unsupervised segmentation to generate pseudo-masks of enhancing tumors on T1-weighted post-contrast images (9911 image slices; 3449 adult patients). Baseline segmentation models were trained and employed within a semi-supervised learning (SSL) framework to refine the pseudo-masks. Following each self-refinement cycle, a new model was trained and tested on a held-out set of 319 manually segmented image slices (93 adult patients), with the SSL cycles continuing until Dice score coefficient (DSC) peaked. DSCs were compared using bootstrap resampling.
Utilizing the best-performing models, two inference methods were compared: (1) conventional full-image segmentation, and (2) a hybrid method augmenting full-image segmentation with detection plus image patch segmentation.
Results
Baseline segmentation models achieved DSC of 0.768 (U-Net), 0.831 (Mask R-CNN), and 0.838 (HRNet), improving with self-refinement to 0.798, 0.871, and 0.873 (each
p
< 0.001), respectively. Hybrid inference outperformed full image segmentation alone: DSC 0.884 (Mask R-CNN) vs. 0.873 (HRNet),
p
< 0.001.
Conclusions
Line annotations mined from PACS can be harnessed within an automated pipeline to produce accurate brain MRI tumor segmentation models without manually segmented training data, providing a mechanism to rapidly establish tumor segmentation capabilities across radiology modalities.
Key Points
•
A brain MRI tumor detection model trained using clinical line measurement annotations mined from PACS was leveraged to automatically generate tumor segmentation pseudo-masks
.
•
An iterative self-refinement process automatically improved pseudo-mask quality, with the best-performing segmentation pipeline achieving a Dice score of 0.884 on a held-out test set
.
•
Tumor line measurement annotations generated in routine clinical radiology practice can be harnessed to develop high-performing segmentation models without manually segmented training data, providing a mechanism to rapidly establish tumor segmentation capabilities across radiology modalities
.
Journal Article
Molecular Features of Resected Melanoma Brain Metastases, Clinical Outcomes, and Responses to Immunotherapy
2023
Importance Central nervous system (CNS)–penetrant systemic therapies have significantly advanced care for patients with melanoma brain metastases. However, improved understanding of the molecular landscape and microenvironment of these lesions is needed to both optimize patient selection and advance treatment approaches. Objective To evaluate how bulk and single-cell genomic features of melanoma brain metastases are associated with clinical outcome and treatment response. Design, Setting, and Participants This cohort study analyzed bulk DNA sequencing and single nuclear RNA-sequencing data from resected melanoma brain metastases and included 94 consecutive patients with a histopathologically confirmed diagnosis of melanoma brain metastasis who underwent surgical resection at a single National Comprehensive Cancer Network cancer center in San Francisco, California, from January 1, 2009, to December 31, 2022. Exposure A Clinical Laboratory Improvement Amendments–certified targeted sequencing assay was used to analyze tumor resection specimens, with a focus onBRAFV600E alteration. For frozen pathologic specimens from CNS treatment-naive patients undergoing surgical resection, commercial single nuclear RNA sequencing approaches were used. Main Outcomes and Measures The primary outcome was overall survival (OS). Secondary outcomes included CNS progression-free survival (PFS), microenvironmental composition with decreased T-cell and macrophage populations, and responses to immunotherapy. Results To correlate molecular status with clinical outcome, Kaplan-Meier survival analysis of 94 consecutive patients (median age, 64 years [range, 24-82 years]; 70 men [74%]) with targetedBRAFalteration testing showed worse median intracranial PFS (BRAFvariant: 3.6 months [IQR, 0.1-30.6 months];BRAFwildtype: 11.0 months [IQR, 0.8-81.5 months];P < .001) and OS (BRAFvariant: 9.8 months [IQR, 2.5-69.4 months];BRAFwildtype: 23.2 months [IQR, 1.1-102.5 months];P = .005; log-rank test) inBRAFV600E variant tumors. Multivariable Cox proportional hazards regression analysis revealed thatBRAFV600E status was an independent variable significantly associated with both PFS (hazard ratio [HR], 2.65; 95% CI, 1.54-4.57;P < .001) and OS (HR, 1.96; 95% CI, 1.08-3.55;P = .03). For the 45 patients with resected melanoma brain metastases undergoing targeted DNA sequencing, molecular classification recapitulated The Cancer Genome Atlas groups (NRASvariant,BRAFvariant,NF1variant, and triple wildtype) with no subtype enrichment within the brain metastasis cohort. On a molecular level,BRAFV600E variant lesions were found to have a significantly decreased tumor mutation burden. Moreover, single nuclear RNA sequencing of treatment-naiveBRAFV600E variant (n = 3) brain metastases compared withBRAFwildtype (n = 3) brain metastases revealed increased immune cell populations inBRAFwildtype tumors (mean [SD], 11% [4.1%] vs 3% [1.6%] CD45-positive cells;P = .04). Survival analysis of postoperative immunotherapy responses byBRAFstatus revealed thatBRAFwildtype lesions were associated with a response to checkpoint inhibition (median OS: with immunotherapy, undefined; without immunotherapy, 13.0 months [range, 1.1-61.7 months];P = .001; log-rank test) whileBRAFvariant lesions (median OS: with immunotherapy, 9.8 months [range, 2.9-39.8 months]; without immunotherapy, 9.5 months [range, 2.5-67.2 months];P = .81; log-rank test) were not. Conclusions and Relevance This molecular analysis of patients with resected melanoma brain metastases found thatBRAFV600E alteration is an important translational biomarker associated with worse clinical outcomes, differential microenvironmental composition, and benefit from immunotherapy. Patients withBRAFV600E variant melanoma brain metastases may thus benefit from alternative CNS-penetrant systemic regimens.
Journal Article
The role of atf4 in hypoxia-induced cell death in cancer
by
Pike, Luke R. G
in
Oncology
2011
Cancer cells survive the harsh oxygen and nutrient deprivation of the tumour microenvironment through the selection of apoptosis-resistant and glycolytic clones (Cairns et al., 2011; Graeber et al., 1996). In particular, the integrated stress response (ISR) has been shown to be pivotal in cancer cell survival in vivo and the resistance of cancer cells to therapy (Harding et al., 2003). In recent years, it has become apparent that increased autophagy is one mechanism by which the ISR can confer resistance to stress (Kroemer et al., 2010). ATF4 is a major transcriptional effector of the integrated stress response in severe hypoxia (<0.01% O₂). ATF4 is a well-established regulator of genes involved in oxidative stress, amino acid synthesis and uptake, lipid metabolism, protein folding, metastasis, and angiogenesis. Recent work has demonstrated an important role of ATF4 in promoting resistance to severe hypoxia through the transcriptional upregulation of MAP1LC3B and ATG5, essential components of the autophagy machinery (Rouschop et al., 2009b; Rzyski et al., 2010). In this work, the author describes several novel ATF4 target genes, and examines their role in the regulation of autophagy and the resistance of cancer cells to severe hypoxia. In the first part of this thesis, the author shows that three BH3-only members of the BCL-2 family of proteins--HRK, PUMA, and NOXA--are upregulated in response to severe hypoxia in an ATF4-dependent manner. In particular, the author shows that the poorly described BH3-only protein HRK is a direct target of transcriptional activation by ATF4, and that HRK induces autophagy in severe hypoxia, thereby providing the first evidence that the integrated stress response can transcriptionally trigger the autophagy process. In contrast to the previously described role of HRK in apoptosis, this thesis demonstrates that HRK can play a pro-survival role in the context of breast cancer cells. In the latter part of this thesis, the author identifies the essential autophagy gene ULK1 as an ISR target. The author shows that ULK1 expression in severe hypoxia is transcriptionally upregulated through direct activation by ATF4. The author identifies ULK1 as a crucial regulator of autophagy and mitophagy in both normoxia and severe hypoxia and shows that ULK1 plays a pivotal role in cancer cell survival. Furthermore, it is shown that human breast cancer patients with high levels of ULK1 relapse earlier than those with low levels of ULK1, thereby identifying ULK1 as a potential target for cancer therapy.
Dissertation
The role of ATF4 in hypoxia-induced cell death in cancer
2011
Cancer cells survive the harsh oxygen and nutrient deprivation of the tumour microenvironment through the selection of apoptosis-resistant and glycolytic clones (Cairns et al., 2011; Graeber et al., 1996). In particular, the integrated stress response (ISR) has been shown to be pivotal in cancer cell survival in vivo and the resistance of cancer cells to therapy (Harding et al., 2003). In recent years, it has become apparent that increased autophagy is one mechanism by which the ISR can confer resistance to stress (Kroemer et al., 2010). ATF4 is a major transcriptional effector of the integrated stress response in severe hypoxia (<0.01% O₂). ATF4 is a well-established regulator of genes involved in oxidative stress, amino acid synthesis and uptake, lipid metabolism, protein folding, metastasis, and angiogenesis. Recent work has demonstrated an important role of ATF4 in promoting resistance to severe hypoxia through the transcriptional upregulation of MAP1LC3B and ATG5, essential components of the autophagy machinery (Rouschop et al., 2009b; Rzyski et al., 2010). In this work, the author describes several novel ATF4 target genes, and examines their role in the regulation of autophagy and the resistance of cancer cells to severe hypoxia. In the first part of this thesis, the author shows that three BH3-only members of the BCL-2 family of proteins--HRK, PUMA, and NOXA--are upregulated in response to severe hypoxia in an ATF4-dependent manner. In particular, the author shows that the poorly described BH3-only protein HRK is a direct target of transcriptional activation by ATF4, and that HRK induces autophagy in severe hypoxia, thereby providing the first evidence that the integrated stress response can transcriptionally trigger the autophagy process. In contrast to the previously described role of HRK in apoptosis, this thesis demonstrates that HRK can play a pro-survival role in the context of breast cancer cells. In the latter part of this thesis, the author identifies the essential autophagy gene ULK1 as an ISR target. The author shows that ULK1 expression in severe hypoxia is transcriptionally upregulated through direct activation by ATF4. The author identifies ULK1 as a crucial regulator of autophagy and mitophagy in both normoxia and severe hypoxia and shows that ULK1 plays a pivotal role in cancer cell survival. Furthermore, it is shown that human breast cancer patients with high levels of ULK1 relapse earlier than those with low levels of ULK1, thereby identifying ULK1 as a potential target for cancer therapy.
Dissertation