Hepatic prohibitin 1 and methionine adenosyltransferase α1 defend against primary and secondary liver cancer metastasis.

BACKGROUND & AIMS: The liver is a common site of cancer metastasis, most commonly from colorectal cancer, and primary liver cancers that have metastasized are associated with poor outcomes. The underlying mechanisms by which the liver defends against these processes are largely unknown. Prohibitin 1 (PHB1) and methionine adenosyltransferase 1A (MAT1A) are highly expressed in the liver. They positively regulate each other and their deletion results in primary liver cancer. Here we investigated their roles in primary and secondary liver cancer metastasis. METHODS: We identified common target genes of PHB1 and MAT1A using a metastasis array, and measured promoter activity and transcription factor binding using luciferase reporter assays and chromatin immunoprecipitation, respectively. We examined how PHB1 or MAT1A loss promotes liver cancer metastasis and whether their loss sensitizes to colorectal liver metastasis (CRLM). RESULTS: Matrix metalloproteinase-7 (MMP-7) is a common target of MAT1A and PHB1 and its induction is responsible for increased migration and invasion when MAT1A or PHB1 is silenced. Mechanistically, PHB1 and MAT1A negatively regulate MMP7 promoter activity via an AP-1 site by repressing the MAFG-FOSB complex. Loss of MAT1A or PHB1 also increased MMP-7 in extracellular vesicles, which were internalized by colon and pancreatic cancer cells to enhance their oncogenicity. Low hepatic MAT1A or PHB1 expression sensitized to CRLM, but not if endogenous hepatic MMP-7 was knocked down first, which lowered CD4+ T cells while increasing CD8+ T cells in the tumor microenvironment. Hepatocytes co-cultured with colorectal cancer cells express less MAT1A/PHB1 but more MMP-7. Consistently, CRLM raised distant hepatocytes' MMP-7 expression in mice and humans. CONCLUSION: We have identified a PHB1/MAT1A-MAFG/FOSB-MMP-7 axis that controls primary liver cancer metastasis and sensitization to CRLM. IMPACT AND IMPLICATIONS: Primary and secondary liver cancer metastasis is associated with poor outcomes but whether the liver has underlying defense mechanism(s) against metastasis is unknown. Here we examined the hypothesis that hepatic prohibitin 1 (PHB1) and methionine adenosyltransferase 1A (MAT1A) cooperate to defend the liver against metastasis. Our studies found PHB1 and MAT1A form a complex that suppresses matrix metalloproteinase-7 (MMP-7) at the transcriptional level and loss of either PHB1 or MAT1A sensitizes the liver to metastasis via MMP-7 induction. Strategies that target the PHB1/MAT1A-MMP-7 axis may be a promising approach for the treatment of primary and secondary liver cancer metastasis.

A chemokine regulatory loop induces cholesterol synthesis in lung-colonizing triple-negative breast cancer cells to fuel metastatic growth.

Triple-negative breast cancer (TNBC) has a high propensity for organ-specific metastasis. However, the underlying mechanisms are not well understood. Here we show that the primary TNBC tumor-derived C-X-C motif chemokines 1/2/8 (CXCL1/2/8) stimulate lung-resident fibroblasts to produce the C-C motif chemokines 2/7 (CCL2/7), which, in turn, activate cholesterol synthesis in lung-colonizing TNBC cells and induce angiogenesis at lung metastatic sites. Inhibiting cholesterol synthesis in lung-colonizing breast tumor cells by pulmonary administration of simvastatin-carrying HER3-targeting nanoparticles reduces angiogenesis and growth of lung metastases in a syngeneic TNBC mouse model. Our findings reveal a novel, chemokine-regulated mechanism for the cholesterol synthesis pathway and a critical role of metastatic site-specific cholesterol synthesis in the pulmonary tropism of TNBC metastasis. The study has implications for the unresolved epidemiological observation that use of cholesterol-lowering drugs has no effect on breast cancer incidence but can unexpectedly reduce breast cancer mortality, suggesting interventions of cholesterol synthesis in lung metastases as an effective treatment to improve survival in individuals with TNBC.

Comparative Proteomic Analysis of HPV(+) Oropharyngeal Squamous Cell Carcinoma Recurrence.

Deintensification therapy for human papillomavirus-related oropharyngeal squamous cell carcinoma (HPV(+) OPSCC) is under active investigation. An adaptive treatment approach based on molecular stratification could identify high-risk patients predisposed to recurrence and better select for appropriate treatment regimens. Collectively, 40 HPV(+) OPSCC FFPE samples (20 disease-free, 20 recurrent) were surveyed using mass spectrometry-based proteomic analysis via data-independent acquisition to obtain fold change and false discovery differences. Ten-year overall survival was 100.0 and 27.7% for HPV(+) disease-free and recurrent cohorts, respectively. Of 1414 quantified proteins, 77 demonstrated significant differential expression. Top enriched functional pathways included those involved in programmed cell death (73 proteins, p = 7.43 × 10-30), apoptosis (73 proteins, p = 5.56 × 10-9), ß-catenin independent WNT signaling (47 proteins, p = 1.45 × 10-15), and Rho GTPase signaling (69 proteins, p = 1.09 × 10-5). PFN1 (p = 1.0 × 10-3), RAD23B (p = 2.9 × 10-4), LDHB (p = 1.0 × 10-3), and HINT1 (p = 3.8 × 10-3) pathways were significantly downregulated in the recurrent cohort. On functional validation via immunohistochemistry (IHC) staining, 46.9% (PFN1), 71.9% (RAD23B), 59.4% (LDHB), and 84.4% (HINT1) of cases were corroborated with mass spectrometry findings. Development of a multilateral molecular signature incorporating these targets may characterize high-risk disease, predict treatment response, and augment current management paradigms in head and neck cancer.

Five-dimensional quantitative low-dose Multitasking dynamic contrast- enhanced MRI: Preliminary study on breast cancer.

PURPOSE: To develop a low-dose Multitasking DCE technique (LD-MT-DCE) for breast imaging, enabling dynamic T1 mapping-based quantitative characterization of tumor blood flow and vascular properties with whole-breast coverage, a spatial resolution of 0.9 × 0.9 × 1.1 mm3 , and a temporal resolution of 1.4 seconds using a 20% gadolinium dose (0.02 mmol/kg). METHODS: Magnetic resonance Multitasking was used to reconstruct 5D images with three spatial dimensions, one T1 recovery dimension for dynamic T1 quantification, and one DCE dimension for contrast kinetics. Kinetic parameters Fp , vp , Ktrans , and ve were estimated from dynamic T1 maps using the two-compartment exchange model. The LD-MT-DCE repeatability and agreement against standard-dose MT-DCE were evaluated in 20 healthy subjects. In 7 patients with triple-negative breast cancer, LD-MT-DCE image quality and diagnostic results were compared with that of standard-dose clinical DCE in the same imaging session. One-way unbalanced analysis of variance with Tukey test was performed to evaluate the statistical significance of the kinetic parameters between control and patient groups. RESULTS: The LD-MT-DCE technique was repeatable, agreed with standard-dose MT-DCE, and showed excellent image quality. The diagnosis using LD-MT-DCE matched well with clinical results. The values of Fp , vp , and Ktrans were significantly different between malignant tumors and normal breast tissue (P < .001, < .001, and < .001, respectively), and between malignant and benign tumors (P = .020, .003, and < .001, respectively). CONCLUSION: The LD-MT-DCE technique was repeatable and showed excellent image quality and equivalent diagnosis compared with standard-dose clinical DCE. The estimated kinetic parameters were capable of differentiating between normal breast tissue and benign and malignant tumors.

Improved survival in women versus men with merkel cell carcinoma.

BACKGROUND: Studies have observed that women have better outcomes than men in melanoma, but less is known about the influence of sex differences on outcomes for other aggressive cutaneous malignancies. OBJECTIVE: To investigate whether women and men have disparate outcomes in Merkel cell carcinoma (MCC). METHODS: Patients with nonmetastatic MCC undergoing surgery and lymph node evaluation were identified from the National Cancer Database (NCDB) and the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier analysis and Cox proportional hazards regression models were used for overall survival, and competing-risks analysis and Fine-Gray models were used for cause-specific and other-cause mortality. RESULTS: The NCDB cohort (n = 4178) included 1516 (36%) women. Women had a consistent survival advantage compared with men in propensity score-matched analysis (66.0% vs 56.8% at 5 years, P < .001) and multivariable Cox regression (hazard ratio, 0.68; 95% confidence interval, 0.61-0.75; P < .001). Similarly, women had a survival advantage in the SEER validation cohort (n = 1202) with 457 (38.0%) women, which was entirely due to differences in MCC-specific mortality (5-year cumulative incidence: 16.4% vs 26.7%, P = .002), with no difference in other-cause mortality (16.8% vs 17.8%, P = .43) observed in propensity score-matched patients. LIMITATIONS: Potential selection bias from a retrospective data set. CONCLUSION: In MCC, women have improved survival compared with men, driven by MCC-related mortality.

Stage I HPV-positive oropharyngeal cancer: Should all patients receive similar treatments?

BACKGROUND: Patients with clinical stage I human papillomavirus (HPV)-positive oropharyngeal squamous cell cancer (OPSCC) according to the American Joint Committee on Cancer (AJCC) eighth edition classification comprise a heterogeneous group formerly classified as stage I to stage IVA according to the seventh edition of the AJCC classification. These patients historically were treated with disparate treatment regimens, particularly with respect to the use of concurrent chemotherapy. METHODS: The National Cancer Data Base was queried for patients with AJCC eighth edition clinical stage I HPV-positive OPSCC (AJCC seventh edition stage T1-2N0-2bM0) who were diagnosed from 2010 to 2014 and underwent definitive radiotherapy. Concurrent chemotherapy with definitive radiotherapy was defined as chemotherapy administered within 7 days of the initiation of radiotherapy. RESULTS: The current analysis included 4473 patients with HPV-positive stage I OPSCC with a median follow-up of 36.3 months. A total of 3127 patients (69.9%) received concurrent chemotherapy. Concurrent chemotherapy was found to be associated with improved overall survival on multivariable analyses (hazard ratio [HR], 0.782; 95% CI, 0.645-0.948 [P = .012]). The effect of chemotherapy on survival varied based on lymph node involvement (P for interaction = .001). Specifically, chemotherapy was associated with improved survival for patients with lymph node-positive stage I disease (stage III-IVA according to the AJCC seventh edition: HR, 0.682; 95% CI, 0.557-0.835 [P < .001]), but not for patients with N0 disease (stage I-II according to the AJCC seventh edition: HR, 1.646; 95% CI, 1.011-2.681 [P = .05]). Similar results were noted among propensity score-matched cohorts. CONCLUSIONS: Treatment with concurrent chemotherapy was associated with improved overall survival for patients with lymph node-positive, but not lymph node-negative, AJCC eighth edition stage I HPV-positive OPSCC undergoing definitive radiotherapy, thereby supporting different treatment paradigms for these patients.

The association between facility volume and overall survival in patients with Merkel cell carcinoma.

BACKGROUND: Merkel cell carcinoma is an uncommon malignancy often requiring multidisciplinary management. The purpose of this study was to determine whether high-volume facilities have improved outcomes in patients with Merkel cell carcinoma relative to lower-volume facilities. METHODS: A total of 5304 patients from the National Cancer Database with stage I-III Merkel cell carcinoma undergoing surgery were analyzed. High-volume facilities were the top 1% by case volume. Multivariable Cox regression and propensity score-matching were performed to account for imbalances between groups. RESULTS: Treatment at high-volume facilities (hazard ratio: 0.74; 95% confidence interval: 0.65-0.84, P < .001) was independently associated with improved overall survival (OS) in multivariable analyses. In propensity score-matched cohorts, 5-year OS was 62.3% at high-volume facilities vs 56.8% at lower-volume facilities (P < .001). Median OS was 111 months at high-volume facilities vs 79 months at lower-volume facilities. CONCLUSION: Treatment at high-volume facilities is associated with improved OS in Merkel cell carcinoma. Given the impracticality of referring all elderly patients with Merkel cell carcinoma to a small number of facilities, methods to mitigate this disparity should be explored.

Impact of insurance on survival in patients < 65 with head & neck cancer treated with radiotherapy.

OBJECTIVES: The United States has a heterogenous health insurance landscape for patients <65 years. We sought to characterise the impact of primary payer on overall survival (OS) in insured patients younger than 65 with head and neck squamous cell carcinoma (HNSCC) treated with definitive radiotherapy. DESIGN/STUDY/PARTICIPANTS: The National Cancer Database was queried for patients <65 years old diagnosed from 2004 to 2014 undergoing definitive radiotherapy ± chemotherapy for cancers of the nasopharynx, oropharynx, hypopharynx and larynx. Uninsured patients and oropharyngeal cancers without known HPV status were excluded. MAIN OUTCOME: Overall survival. RESULTS: Overall, 27 292 insured patients were identified, including 17 060 (62.5%) with private insurance. Median follow-up was 52.1 months. In multivariable models, patients receiving Medicaid (HR = 1.66, 95% CI 1.57-1.75, P < .001), Medicare (HR = 1.64, 95% CI 1.55-1.73, P < .001) and other government insurance (HR = 1.44, 95% CI 1.29-1., P < .001) had independently increased mortality in comparison to those with private insurance. In propensity score-matched cohorts, 5-year OS was 65.5% vs 50.6% for privately vs government-insured patients, respectively (P < .001). In multivariable subgroup analysis, private insurance was associated with improved survival in all subgroups. However, the magnitude of this effect was most pronounced in patients with HPV-positive oropharyngeal cancer vs non-HPV-related cancer (interaction P < .001), younger patients (interaction P = .001), and those without comorbidity (interaction P < .001). CONCLUSIONS: Patients <65 with HNSCC undergoing definitive radiation with private health insurance have markedly longer survival relative to patients with government-sponsored insurance. This illustrates that increasing access to care may be necessary, but is not sufficient, to mitigate the significant disparities in the US healthcare system.

Immune microenvironments in solid tumors: new targets for therapy.

Leukocytes and their soluble mediators play important regulatory roles in all aspects of solid tumor development. While immunotherapeutic strategies have conceptually held clinical promise, with the exception of a small percentage of patients, they have failed to demonstrate effective, consistent, and durable anti-cancer responses. Several subtypes of leukocytes that commonly infiltrate solid tumors harbor immunosuppressive activity and undoubtedly restrict the effectiveness of these strategies. Several of these same immune cells also foster tumor development by expression of potent protumor mediators. Given recent evidence revealing that immune-based mechanisms regulate the response to conventional cytotoxic therapy, it seems reasonable to speculate that tumor progression could be effectively diminished by combining cytotoxic strategies with therapies that blunt protumor immune-based effectors and/or neutralize those that instead impede development of desired anti-tumor immunity, thus providing synergistic effects between traditional cytotoxic and immune-modulatory approaches.

Development of a novel salivary gland cancer lymph node staging system.

BACKGROUND: Current lymph node (LN) staging for salivary gland cancer (SGC) is extrapolated from mucosal head and neck squamous cell carcinoma. However, given its unique biology and clinical behavior, it is possible that a SGC-specific LN staging system would be more accurate. METHODS: Patients from the National Cancer Data Base with nonmetastatic SGC of the head and neck who were diagnosed from 2004 through 2013 and underwent surgical resection and neck dissection removing at least 10 LNs were included. Multivariable models were constructed to assess the association between survival and LN factors, including number of metastatic LNs, extranodal extension, LN size, and lower LN involvement. RESULTS: Overall, 4520 patients met the inclusion criteria. An increasing number of metastatic LNs was found to be strongly associated with worse survival without plateau. The risk of death increased more rapidly up to 4 LNs (hazard ratio, 1.34; 95% confidence interval, 1.27-1.41 [P < .001]), and was more gradual for additional LNs >4 (hazard ratio, 1.02; 95% confidence interval, 1.01-1.03 [P < .001]). LN size, extranodal extension, and lower LN involvement appeared to have no impact on survival when accounting for the number of metastatic LNs. Recursive partitioning analysis was used to create a novel SGC LN staging system in which N0 indicates 0 positive LNs, N1 indicates 1 to 2 positive LNs, N2 indicates 3 to 21 positive LNs, and N3 indicates ≥ 22 positive LNs. This system exhibited greater concordance than the current American Joint Committee on Cancer (eighth edition) system. CONCLUSIONS: Quantitative LN burden is an important determinant of survival in patients with SGC. Use of this variable may improve SGC staging. Cancer 2018. © 2018 American Cancer Society.

Treatment at high-volume facilities and academic centers is independently associated with improved survival in patients with locally advanced head and neck cancer.

BACKGROUND: The treatment of head and neck cancers is complex and associated with significant morbidity, requiring multidisciplinary care and physician expertise. Thus, facility characteristics, such as clinical volume and academic status, may influence outcomes. METHODS: The current study included 46,567 patients taken from the National Cancer Data Base who were diagnosed with locally advanced invasive squamous cell carcinomas of the oropharynx, larynx, and hypopharynx and were undergoing definitive radiotherapy. High-volume facilities (HVFs) were defined as the top 1% of centers by the number of patients treated from 2004 through 2012. Multivariable Cox regression and propensity score matching were performed to account for imbalances in covariates. RESULTS: The median follow-up was 55.1 months. Treatment at a HVF (hazard ratio, 0.798; 95% confidence interval, 0.753-0.845 [P<.001]) and treatment at an academic facility (hazard ratio, 0.897; 95% confidence interval, 0.871-0.923 [P<.001]) were found to be independently associated with improved overall survival in multivariable analysis. In propensity score-matched cohorts, the 5-year overall survival rate was 61.6% versus 55.5% for patients treated at an HVF versus lower-volume facilities, respectively (P<.001). Similarly, the 5-year overall survival rate was 52.3% versus 49.7% for patients treated at academic versus nonacademic facilities (P<.001). Analysis of facility volume as a continuous variable demonstrated continual improvement in survival with an increased number of patients treated. The impact of facility volume and academic designation on survival was observed when using a variety of thresholds to define HVF, and across the vast majority of subgroups, including both oropharyngeal and nonoropharyngeal subsites. CONCLUSIONS: Patients with locally advanced head and neck squamous cell carcinoma who are undergoing curative radiotherapy at HVFs and academic centers appear to have improved survival. Cancer 2017;123:3933-42. © 2017 American Cancer Society.

Combined high-intensity local treatment and systemic therapy in metastatic head and neck squamous cell carcinoma: An analysis of the National Cancer Data Base.

BACKGROUND: There is increasing evidence that primary tumor ablation can improve survival for some cancer patients with distant metastases. This may be particularly applicable to head and neck squamous cell carcinoma (HNSCC) because of its tropism for locoregional progression. METHODS: This study included patients with metastatic HNSCC undergoing systemic therapy identified in the National Cancer Data Base. High-intensity local treatment was defined as radiation doses ≥ 60 Gy or oncologic resection of the primary tumor. Multivariate Cox regression, propensity score matching, landmark analysis, and subgroup analysis were performed to account for imbalances in covariates, including adjustments for the number and location of metastatic sites in the subset of patients with this information available. RESULTS: In all, 3269 patients were included (median follow-up, 51.5 months). Patients undergoing systemic therapy with local treatment had improved survival in comparison with patients receiving systemic therapy alone in propensity score-matched cohorts (2-year overall survival, 34.2% vs 20.6%; P < .001). Improved survival was associated only with patients receiving high-intensity local treatment, whereas those receiving lower-intensity local treatment had survival similar to that of patients receiving systemic therapy without local treatment. The impact of high-intensity local therapy was time-dependent, with a stronger impact within the first 6 months after the diagnosis (adjusted hazard ratio [AHR], 0.255; 95% confidence interval [CI], 0.210-0.309; P < .001) in comparison with more than 6 months after the diagnosis (AHR, 0.622; 95% CI, 0.561-0.689; P < .001) in the multivariate analysis. A benefit was seen in all subgroups, in landmark analyses of 1-, 2-, and 3-year survivors, and when adjusting for the number and location of metastatic sites. CONCLUSIONS: Aggressive local treatment warrants prospective evaluation for select patients with metastatic HNSCC. Cancer 2017;123:4583-4593. © 2017 American Cancer Society.

The toxicity and efficacy of concomitant chemoradiotherapy in patients aged 70 years and older with oropharyngeal carcinoma in the intensity-modulated radiotherapy era.

BACKGROUND: Despite controversy surrounding its benefit, the use of concomitant chemoradiotherapy (CCRT) in patients with oropharyngeal squamous cell carcinoma (OPSCC) who are aged > 70 years is increasing. However, to the authors' knowledge, few studies to date have compared the outcomes of different systemic treatments in this population. METHODS: Records from 74 patients aged ≥ 70 years with stage III to stage IVB OPSCC who were undergoing CCRT from 2002 to 2013 at a single institution were reviewed. Patients were stratified according to the systemic therapy received, including cisplatin, carboplatin with either 5-fluorouracil or paclitaxel (CARB), or cetuximab to compare oncologic outcome and toxicity. RESULTS: The median follow-up was 36 months. The median age of the patients was 75.3 years (range, 70-91 years), with significantly older patients receiving cetuximab (P = .03). A total of 28, 20, and 26 patients, respectively, received CCRT with cisplatin, CARB, and cetuximab. RT interruptions of > 1 day were needed in 4% of patients receiving cisplatin, 20% of patients receiving CARB, and 15% of patients receiving cetuximab (P = .19). Unplanned hospitalizations during CCRT occurred in 25%, 55%, and 58%, respectively, of patients receiving cisplatin, CARB, and cetuximab (P = .03). There were 2 treatment-related deaths, both of which occurred among the patients who were treated with cetuximab. At 5 years, locoregional control was achieved in 100%, 88%, and 60% (P<.001), respectively, and the overall survival rate was 87%, 61%, and 47% (P = .03), respectively, among patients treated with cisplatin, CARB, and cetuximab. CONCLUSIONS: Toxicity from CCRT remains a challenge for older adults with OPSCC. Herein, the authors found no evidence that this toxicity was mitigated by treatment with cetuximab. Nevertheless, a subset of patients aged ≥70 years appear to tolerate cisplatin-based treatment with acceptable toxicity and excellent outcomes. Further identification of this patient subgroup is crucial to optimize therapy for older patients with OPSCC. Cancer 2017;123:1345-1353. © 2016 American Cancer Society.

Impact of concomitant chemoradiation on survival for patients with T1-2N1 head and neck cancer.

BACKGROUND: Single-modality radiotherapy is considered a standard-of-care option for certain stage III, T1-2N1 head and neck squamous cell carcinomas (HNSCCs). The role of concomitant chemoradiation is not well established because there have been no studies comparing chemoradiation with radiation alone in this population. METHODS: This study analyzed patients in the National Cancer Data Base with cT1-2N1M0 invasive squamous cell carcinomas of the oropharynx, larynx, and hypopharynx who were diagnosed between 2004 and 2012 and were undergoing definitive radiation. Patients who were undergoing surgery before radiation with unknown follow-up or for whom either the receipt or timing of chemotherapy was unknown were excluded. RESULTS: In all, 5030 patients with T1-2N1 oropharyngeal, laryngeal, or hypopharyngeal cancer were included. The median follow-up was 56.8 months (95% confidence interval [CI], 55.7-58.6 months). Overall, 68% of the patients received concomitant chemoradiation (CCRT). The use of CCRT significantly increased during the time period of this study from 53% in 2004 to 78% in 2012 (P < .001). CCRT was associated with improved overall survival (OS) in comparison with radiation alone in a multivariate analysis (hazard ratio [HR], 0.80; 95% CI, 0.72-0.88; P < .001). In propensity score-adjusted analyses, CCRT remained significantly associated with improved OS, with 5-year OS rates of 63.5% (95% CI, 60.7%-66.2%) and 55.6% (95% CI, 52.7%-58.4%; P < .001) with CCRT and radiation alone, respectively. Subgroup analyses showed a benefit across the majority of subgroups, including patients with oropharyngeal cancer (HR, 0.74; 95% CI, 0.65-0.85; P < .001). CONCLUSIONS: Concomitant chemoradiation is associated with improved survival for patients with T1-2N1 HNSCC. Prospective trials in this population should be pursued. Cancer 2017;123:1555-1565. © 2017 American Cancer Society.

Clinical experience using a video-guided spirometry system for deep inhalation breath-hold radiotherapy of left-sided breast cancer.

The purpose was to report clinical experience of a video-guided spirometry system in applying deep inhalation breath-hold (DIBH) radiotherapy for left-sided breast cancer, and to study the systematic and random uncertainties, intra- and interfraction motion and impact on cardiac dose associated with DIBH. The data from 28 left-sided breast cancer patients treated with spirometer-guided DIBH radiation were studied. Dosimetric comparisons between free-breathing (FB) and DIBH plans were performed. The distance between the heart and chest wall measured on the digitally reconstructed radiographs (DRR) and MV portal images, dDRR(DIBH) and dport(DIBH), respectively, was compared as a measure of DIBH setup uncertainty. The difference (Δd) between dDRR(DIBH) and dport(DIBH) was defined as the systematic uncertainty. The standard deviation of Δd for each patient was defined as the random uncertainty. MV cine images during radiation were acquired. Affine registrations of the cine images acquired during one fraction and multiple fractions were performed to study the intra- and interfraction motion of the chest wall. The median chest wall motion was used as the metric for intra- and interfraction analysis. Breast motions in superior-inferior (SI) direction and "AP" (defined on the DRR or MV portal image as the direction perpendicular to the SI direction) are reported. Systematic and random uncertainties of 3.8 mm and 2mm, respectively, were found for this spirometer-guided DIBH treatment. MV cine analysis showed that intrafraction chest wall motions during DIBH were 0.3mm in "AP" and 0.6 mm in SI. The interfraction chest wall motions were 3.6 mm in "AP" and 3.4 mm in SI. Utilization of DIBH with this spirometry system led to a statistically significant reduction of cardiac dose relative to FB treatment. The DIBH using video-guided spirometry provided reproducible cardiac sparing with minimal intra- and interfraction chest wall motion, and thus is a valuable adjunct to modern breast treatment techniques.

Single-cell and spatial profiling identify three response trajectories to pembrolizumab and radiation therapy in triple negative breast cancer.

Strategies are needed to better identify patients that will benefit from immunotherapy alone or who may require additional therapies like chemotherapy or radiotherapy to overcome resistance. Here we employ single-cell transcriptomics and spatial proteomics to profile triple negative breast cancer biopsies taken at baseline, after one cycle of pembrolizumab, and after a second cycle of pembrolizumab given with radiotherapy. Non-responders lack immune infiltrate before and after therapy and exhibit minimal therapy-induced immune changes. Responding tumors form two groups that are distinguishable by a classifier prior to therapy, with one showing high major histocompatibility complex expression, evidence of tertiary lymphoid structures, and displaying anti-tumor immunity before treatment. The other responder group resembles non-responders at baseline and mounts a maximal immune response, characterized by cytotoxic T cell and antigen presenting myeloid cell interactions, only after combination therapy, which is mirrored in a murine model of triple negative breast cancer.

Activated T cell therapy targeting glioblastoma cancer stem cells.

Naïve T cells become effector T cells following stimulation by antigen-loaded dendritic cells (DCs) and sequential cytokine activation. We aimed to develop procedures to efficiently activate T cells with tumor-associated antigens (TAAs) to glioblastoma (GBM) stem cells. To remove antigen presentation outside of the immunosuppressive tumor milieu, three different glioma stem cell (GSC) specific antigen sources to load DCs were compared in their ability to stimulate lymphocytes. An activated T cell (ATC) protocol including cytokine activation and expansion in culture to target GSCs was generated and optimized for a planned phase I clinical trial. We compared three different antigen-loading methods on DCs to effectively activate T cells, which were GBM patient-derived GSC-lysate, acid-eluate of GSCs and synthetic peptides derived from proteins expressed in GSCs. DCs derived from HLA-A2 positive blood sample were loaded with TAAs. Autologous T cells were activated by co-culturing with loaded DCs. Efficiency and cytotoxicity of ATCs were evaluated by targeting TAA-pulsed DCs or T2 cells, GSCs, or autologous PHA-blasts. Characteristics of ATCs were evaluated by Flow Cytometry and ELISpot assay, which showed increased number of ATCs secreting IFN-γ targeting GSCs as compared with non-activated T cells and unloaded target cells. Neither GSC-lysate nor acid-eluate loading showed enhancement in response of ATCs but the synthetic peptide pool showed significantly increased IFN-γ secretion and increased cytotoxicity towards target cells. These results demonstrate that ATCs activated using a TAA synthetic peptide pool efficiently enhance cytotoxicity specifically to target cells including GSC.

Association of x-ray velocimetry (XV) ventilation analysis compared to spirometry.

Introduction: X-ray Velocimetry (XV) ventilation analysis is a 4-dimensional imaging-based method for quantifying regional ventilation, aiding in the assessment of lung function. We examined the performance characteristics of XV ventilation analysis by examining correlation to spirometry and measurement repeatability. Methods: XV analysis was assessed in 27 patients receiving thoracic radiotherapy for non-lung cancer malignancies. Measurements were obtained pre-treatment and at 4 and 12-months post-treatment. XV metrics such as ventilation defect percent (VDP) and regional ventilation heterogeneity (VH) were compared to spirometry at each time point, using correlation analysis. Repeatability was assessed between multiple runs of the analysis algorithm, as well as between multiple breaths in the same patient. Change in VH and VDP in a case series over 12 months was used to determine effect size and estimate sample sizes for future studies. Results: VDP and VH were found to significantly correlate with FEV1 and FEV1/FVC (range: -0.36 to -0.57; p < 0.05). Repeatability tests demonstrated that VDP and VH had less than 2% variability within runs and less than 8% change in metrics between breaths. Three cases were used to illustrate the advantage of XV over spirometry, where XV indicated a change in lung function that was either undetectable or delayed in detection by spirometry. Case A demonstrated an improvement in XV metrics over time despite stable spirometric values. Case B demonstrated a decline in XV metrics as early as 4-months, although spirometric values did not change until 12-months. Case C demonstrated a decline in XV metrics at 12 months post-treatment while spirometric values remained normal throughout the study. Based on the effect sizes in each case, sample sizes ranging from 10 to 38 patients would provide 90% power for future studies aiming to detect similar changes. Conclusions: The performance and safety of XV analysis make it ideal for both clinical and research applications across most lung indications. Our results support continued research and provide a basis for powering future studies using XV as an endpoint to examine lung health and determine therapeutic efficacy.

A Single-Institution Retrospective Study of Three-Fraction HDR Accelerated Partial Breast Irradiation.

PURPOSE: Accelerated partial breast irradiation (APBI) delivered with high-dose-rate brachytherapy is a standard of care treatment typically delivered over 10 fractions. The TRIUMPH-T multi-institutional study recently demonstrated promising results using a shorter three fraction regimen, however there are limited additional published series using this regimen. Here, we report our experience and outcomes for patients treated as per the TRIUMPH-T regimen. METHODS AND MATERIALS: This study was a retrospective single-institution analysis of patients who underwent lumpectomy followed by APBI (22.5 Gy in 3 fractions delivered over 2-3 days) using a Strut Adjusted Volume Implant (SAVI) applicator between November 2016 and January 2021. Dose-volume metrics were obtained from the clinically treated plan. Chart review was performed to determine locoregional recurrence and toxicities according to CTCAE v5.0. RESULTS: Between 2016 and 2021, 31 patients were treated per the TRIUMPH-T protocol. Median followup was 31 months from completion of brachytherapy. There were no acute/late Grade 3 or higher toxicities. Cumulative late Grade 1 and 2 toxicities were seen in 58.1% and 9.7% of patients, respectively. Of note, four patients experienced locoregional recurrence: three ipsilateral breast tumor recurrences and one nodal recurrence. All three ipsilateral breast tumor recurrences occurred in patients who would be classified as "cautionary" based on ASTRO consensus guidelines due to age ≤50, lobular histology, or high grade. CONCLUSIONS: Three-fraction HDR brachytherapy APBI was well-tolerated with no grade 3 or higher toxicities and an acceptably small percentage of grade 2 toxicities. Given the small sample size, the number of recurrences suggests that attention to appropriate patient selection is necessary until more long-term followup data is available.

Chronic antigen in solid tumors drives a distinct program of T cell residence.

Analyses of healthy tissue reveal signatures that identify resident memory CD8+ T cells (TRM), which survey tissues without recirculating. The density of TRM phenotype cells within solid tumors correlates favorably with prognosis, suggesting that intratumoral residents control cancer. However, residence has not been directly tested, and intratumoral TRM phenotype cells could instead reflect aspects of the microenvironment that correlate with prognosis. Using a breast cancer model in mice, we found that conventional TRM markers do not inform the tumor residence of either bystander or tumor-specific cells, which exhibit further distinct phenotypes in the tumor microenvironment and healthy mammary tissue. Rather, tumor-specific, stem progenitor CD8+ T cells migrate to tumors and become resident while acquiring select markers of exhaustion. These data indicate that tonic antigen stimulation and the tumor environment drive distinct programs of residence compared with healthy tissues and that tumor immunity is sustained by continued migration of tumor-specific stem cells.