The Safety of Bridging Radiation with Anti-BCMA CAR T-Cell Therapy for Multiple Myeloma.

PURPOSE: B-cell maturation antigen (BCMA)-targeted chimeric antigen receptor (CAR) T cells (CART-BCMA) are a promising treatment for relapsed/refractory multiple myeloma (r/rMM). We evaluated the safety and feasibility of bridging radiation (RT) in subjects treated on a phase I trial of CART-BCMA. EXPERIMENTAL DESIGN: Twenty-five r/rMM subjects were treated in three cohorts with two doses of CART-BCMA cells ± cyclophosphamide. We retrospectively analyzed toxicity, response, and CART manufacturing data based on RT receipt. RESULTS: Thirteen subjects received no RT <1 year before CART infusion (Group A). Eight subjects received RT <1 year before CART infusion (Group B) with median time from RT to apheresis of 114 days (range 40-301). Four subjects received bridging-RT (Group C) with a median dose of 22 Gy and time from RT to infusion of 25 days (range 18-35). Group C had qualitatively lower rates of grade 4 (G4) hematologic toxicities (25%) versus A (61.5%) and B (62.5%). G3-4 neurotoxicity occurred in 7.7%, 25%, and 25% in Group A, B, and C, respectively. G3-4 cytokine release syndrome was observed in 38.5%, 25%, and 25% in Group A, B, and C, respectively. Partial response or better was observed in 54%, 38%, and 50% of Group A, B, and C, respectively. RT administered <1 year (P = 0.002) and <100 days (P = 0.069) before apheresis was associated with lower in vitro proliferation during manufacturing; however, in vivo CART-BCMA expansion appeared similar across groups. CONCLUSIONS: Bridging-RT appeared safe and feasible with CART-BCMA therapy in our r/rMM patients, though larger future studies are needed to draw definitive conclusions.

Bridging Radiation Therapy Before Commercial Chimeric Antigen Receptor T-Cell Therapy for Relapsed or Refractory Aggressive B-Cell Lymphoma.

PURPOSE: CD19-targeting chimeric antigen receptor T-cell (CART) therapy has emerged as a promising treatment for relapsed/refractory aggressive B-cell lymphoma (r/rABL), culminating in 2 US Food and Drug Administration-approved therapies: tisagenlecleucel (tisa-cel) and axicabtagene ciloleucel (axi-cel). Following leukapheresis and in preparation for CART infusion, contemporary bridging and lymphodepletion regimens rely mostly on cytotoxic chemotherapy. Here, in a cohort of patients treated with commercial tisa-cel and axi-cel, we show that bridging-RT may offer a supplemental approach. METHODS AND MATERIALS: Thirty-one patients receiving commercial tisa-cel (n = 13) or axi-cel (n = 18) between August 2018 and February 2019 for r/rABL were retrospectively reviewed. Patients were categorized into 2 groups: (1) bridging-RT within 30 days of CART infusion or (2) nonbridging-RT (NBRT), in which patients received either remote RT greater than 30 days before CART infusion or no prior RT. RESULTS: Five patients received bridging-RT within 30 days of CART infusion. Median bridging-RT dose was 37.5 Gy and was completed a median of 13 days before infusion. No grade 3 (G3) or higher RT-toxicities occurred. No patients in the bridging-RT group experienced G3 or higher CART-related toxicities (CRS or neurotoxicity), and 23% (n = 6) and 15% (n = 4) experienced G3-5 CRS and G3-5 neurotoxicity in the NBRT group, respectively. Overall treatment response in the bridging-RT and NBRT groups was 80% and 64%, respectively. The axi-cel CART product was associated with CRS (odds ratio [OR] = 26.67, P = .001) and CRS correlated with neurotoxicity (OR = 12.22, P = .028). There was a trend toward an association for CRS with metabolic tumor volume (OR = 1.06/mL, P = .141) and TLG (OR = 1.01/mL x standard uptake value, P = .099). CONCLUSIONS: Bridging-RT before commercial CART does not appear to increase the risk for CART-related toxicities or negatively affect outcomes in r/rABL patients. No G3 or higher RT-toxicities occurred in this series. Pretreatment metabolic tumor burden may be associated with CART-associated CRS; however, larger patient numbers are required to elucidate significant associations. Future work to prospectively assess the value of bridging-RT is warranted.

Acute neurologic toxicity of palliative radiotherapy for brain metastases in patients receiving immune checkpoint blockade.

BACKGROUND: The interaction between immune checkpoint blockade (ICB) and radiation (RT) for brain metastases has not been well understood. Given that acute neurotoxicity from this combination is not well characterized, we reviewed patients receiving ICB and RT for brain metastases. METHODS: Patients treated with ICB and cranial RT from 2010 through 2017 were reviewed. ICB and RT must have been administered within 30 days of each other. Treatment parameters, performance status, symptoms prior to treatment, and toxicity were extracted from the electronic medical record. Survival was calculated from the end of RT to last follow-up or death. RESULTS: Seventy-eight patients were included. Median follow-up was 177 days (range, 12-1603). Median age was 64 years old (range, 29-98) and 47 (63%) were male. The main tumor types were melanoma (n = 47) and nonsmall-cell lung cancer (n = 19). Fifty-seven patients were treated with stereotactic radiosurgery (SRS) and 21 with whole-brain radiotherapy (WBRT). Most patients received single-agent ICB, though 4 patients received nivolumab and ipilimumab. Forty-one (53%) patients reported no neurologic toxicity. Grade 2 or greater neurologic toxicities were reported in 12 (21%) and 8 (38%) patients in the SRS and WBRT groups, respectively. WBRT was associated with a greater risk of any neurotoxicity, though there was no correlation between ICB agent and toxicity. Sequencing of ICB and RT (ie, <30 days vs <7) did not influence rates of toxicity. CONCLUSIONS: ICB during SRS or WBRT does not appear to worsen acute neurotoxicity compared to historical controls of RT alone.

Evaluating the Impact of Secure Mobile Messaging on Communication and Cancer Care Team Satisfaction in a Large Radiation Oncology Clinic.

PURPOSE: Communication is crucial in any clinical environment for efficient delivery of care and ensuring patient safety. A 2016 National Database of Nursing Quality Indicators questionnaire indicated poor physician-nurse satisfaction with communication in our department. We addressed gaps in our communication procedures by implementing a communication policy with a secure mobile messaging platform, and we surveyed care team members to evaluate the effectiveness of the implementation. METHODS: We designed a policy around best communication practices and implemented a secure mobile messaging platform, Cureatr, which enables closed-loop, two-way communication that is compliant with the Health Insurance Portability and Accountability Act. Pre- and postimplementation surveys evaluated self-reported impression of efficiency, timeliness, effectiveness, and overall quality of communication, which were scored on a 5-point Likert scale. The number of messages sent was evaluated as a measure of uptake in use, and patient navigation data were queried to measure changes in clinic workflow. RESULTS: After implementation of Cureatr and a communication policy, survey responses demonstrated a clear improvement in staff satisfaction with the efficiency, timeliness, effectiveness, and overall quality of communication. The number of messages sent reflected a progressive increase in use of Cureatr; however, a consistent improvement in clinical workflow as measured by a decrease in patient in-room time was not appreciated. CONCLUSION: Implementing a secure messaging application with a communication policy improved cancer care team satisfaction with communication on all levels. Additional work is needed to evaluate the impact of secure messaging on clinical workflows, patient satisfaction, and staff well-being.

Long-term Survival After Treating Cardiac Metastasis With Radiation and Immune Therapy: A Case Report.

Cardiac metastases are a rare clinical entity and they generally portend a poor prognosis. Management is generally directed toward symptom control and maintaining cardiac function; however, long-term survival is rare. Here, we report a case of isolated metastatic urothelial cell carcinoma to the right ventricle that was functionally limiting the patient. The metastasis was successfully palliated for 17 months following radiation and immune therapy; however, disease progression in and around his heart ultimately led to a cardiac arrest.

Stereotactic body proton therapy for liver tumors: Dosimetric advantages and their radiobiological and clinical implications.

BACKGROUND AND PURPOSE: Photon Stereotactic Body Radiotherapy (SBRT) for primary and metastatic tumors of the liver is challenging for larger lesions. An in silico comparison of paired SBRT and Stereotactic Body Proton Therapy (SBPT) plans was performed to understand the potential advantages of SBPT as a function of tumor size and location. METHODS AND MATERIALS: Theoretical tumor volumes with maximum diameter of 1-10 cm were contoured in the dome, right inferior, left medial, and central locations. SBRT and SBPT plans were generated to deliver 50 Gy in 5 fractions, max dose <135%. When organs-at-risk (OAR) constraints were exceeded, hypothetical plans (not clinically acceptable) were generated for comparison. Liver normal tissue complication probability (NTCP) models were applied to evaluate differences between treatment modalities. RESULTS: SBRT and SBPT were able to meet target goals and OAR constraints for lesions up to 7 cm and 9 cm diameter, respectively. SBPT plans resulted in a higher integral gross target dose for all lesions up to 7 cm (mean dose 57.8 ±â€¯2.3 Gy to 64.1 ±â€¯2.2 Gy, p < 0.01). Simultaneously, SBPT spared dose to the uninvolved liver in all locations (from 11.5 ±â€¯5.3 Gy to 8.6 ±â€¯4.4 Gy, p < 0.01), resulting in lower NTCP particularly for larger targets in the dome and central locations. SBPT also spared duodenal dose across all sizes and positions (from 7.3 ±â€¯1.1 Gy to 1.1 ±â€¯0.3 Gy, p < 0.05). CONCLUSION: The main advantages of SBPT over SBRT is meeting plan goals and constrains for larger targets, particularly dome and central locations, and sparing dose to uninvolved liver. For such patients, SBPT may allow improvements in tumor control and treatment safety.

Protein Phosphatase 2A Inhibition with LB100 Enhances Radiation-Induced Mitotic Catastrophe and Tumor Growth Delay in Glioblastoma.

Protein phosphatase 2A (PP2A) is a tumor suppressor whose function is lost in many cancers. An emerging, though counterintuitive, therapeutic approach is inhibition of PP2A to drive damaged cells through the cell cycle, sensitizing them to radiotherapy. We investigated the effects of PP2A inhibition on U251 glioblastoma cells following radiation treatment in vitro and in a xenograft mouse model in vivo. Radiotherapy alone augmented PP2A activity, though this was significantly attenuated with combination LB100 treatment. LB100 treatment yielded a radiation dose enhancement factor of 1.45 and increased the rate of postradiation mitotic catastrophe at 72 and 96 hours. Glioblastoma cells treated with combination LB100 and radiotherapy maintained increased γ-H2AX expression at 24 hours, diminishing cellular repair of radiation-induced DNA double-strand breaks. Combination therapy significantly enhanced tumor growth delay and mouse survival and decreased p53 expression 3.68-fold, compared with radiotherapy alone. LB100 treatment effectively inhibited PP2A activity and enhanced U251 glioblastoma radiosensitivity in vitro and in vivo. Combination treatment with LB100 and radiation significantly delayed tumor growth, prolonging survival. The mechanism of radiosensitization appears to be related to increased mitotic catastrophe, decreased capacity for repair of DNA double-strand breaks, and diminished p53 DNA-damage response pathway activity.

Obstructive voiding symptoms following stereotactic body radiation therapy for prostate cancer.

BACKGROUND: Obstructive voiding symptoms (OVS) are common following prostate cancer treatment with radiation therapy. The risk of urinary retention (UR) following hypofractionated radiotherapy has yet to be fully elucidated. This study sought to evaluate OVS and UR requiring catheterization following SBRT for prostate cancer. METHODS: Patients treated with SBRT for localized prostate cancer from February 2008 to July 2011 at Georgetown University were included in this study. Treatment was delivered using the CyberKnife® with doses of 35 Gy-36.25 Gy in 5 fractions. UR was prospectively scored using the CTCAE v.3. Patient-reported OVS were assessed using the IPSS-obstructive subdomain at baseline and at 1, 3, 6, 9, 12, 18 and 24 months. Associated bother was evaluated via the EPIC-26. RESULTS: 269 patients at a median age of 69 years received SBRT with a median follow-up of 3 years. The mean prostate volume was 39 cc. Prior to treatment, 50.6% of patients reported moderate to severe lower urinary track symptoms per the IPSS and 6.7% felt that weak urine stream and/or incomplete emptying were a moderate to big problem. The 2-year actuarial incidence rates of acute and late UR ≥ grade 2 were 39.5% and 41.4%. Alpha-antagonist utilization rose at one month (58%) and 18 months (48%) post-treatment. However, Grade 3 UR was low with only 4 men (1.5%) requiring catheterization and/or TURP. A mean baseline IPSS-obstructive score of 3.6 significantly increased to 5.0 at 1 month (p < 0.0001); however, it returned to baseline in 92.6% within a median time of 3 months. Late increases in OVS were common, but transient. Only 7.1% of patients felt that weak urine stream and/or incomplete emptying was a moderate to big problem at two years post-SBRT (p = 0.6854). CONCLUSIONS: SBRT treatment caused an acute increase in OVS which peaked within the first month post-treatment, though acute UR requiring catheterization was rare. OVS returned to baseline in > 90% of patients within a median time of three months. Transient Late increases in OVS were common. However, less than 10% of patients felt that OVS were a moderate to big problem at two years post-SBRT.

Interferon ß-1b directly modulates human neural stem/progenitor cell fate.

Interferon beta (IFN-ß) is a mainline treatment for multiple sclerosis (MS); however its exact mechanism of action is not completely understood. IFN-ß is known as an immunomodulator; although recent evidence suggests that IFN-ß may also act directly on neural stem/progenitor cells (NPCs) in the central nervous system (CNS). NPCs can differentiate into all neural lineage cells, which could contribute to the remyelination and repair of MS lesions. Understanding how IFN-ß influences NPC physiology is critical to develop more specific therapies that can better assist this repair process. In this study, we investigated the effects of IFN ß-1b (Betaseron®) on human NPCs in vitro (hNPCs). Our data demonstrate a dose-dependent response of hNPCs to IFN ß-1b treatment via sustained proliferation and differentiation. Furthermore, we offer insight into the signaling pathways involved in these mechanisms. Overall, this study shows a direct effect of IFN ß-1b on hNPCs and highlights the need to further understand how current MS treatments can modulate endogenous NPC populations within the CNS.

SloR modulation of the Streptococcus mutans acid tolerance response involves the GcrR response regulator as an essential intermediary.

Streptococcus mutans, the primary causative agent of human dental caries, grows as a biofilm on the tooth surface, where it metabolizes dietary carbohydrates and generates acid byproducts that demineralize tooth enamel. A drop in plaque pH stimulates an adaptive acid-tolerance response (ATR) in this oral pathogen that allows it to survive acid challenge at pHs as low as 3.0. In the present study, we describe the growth of an S. mutans mutant, GMS901, that harbours an insertion-deletion mutation in gcrR, a gene that encodes a transcriptional regulatory protein. The mutant is acid-sensitive and significantly compromised in its ATR relative to the UA159 wild-type progenitor strain. Consistent with these findings are the results of real-time quantitative RT-PCR (qRT-PCR) experiments that support the GcrR-regulated expression of known ATR genes, including atpA/E and ffh. Although we observed gcrR transcription that was not responsive to acidic pH, we did note a significant increase in gcrR expression when S. mutans cells were grown in a manganese-restricted medium. Interestingly, the results of gel mobility shift assays indicate that the S. mutans SloR metalloregulatory protein is a potential regulator of gcrR by virtue of its manganese-dependent binding to the gcrR promoter region, and expression studies support the hypothesis that sloR transcription is responsive to manganese deprivation and acidic pH. Taking these results together, we propose that SloR-Mn modulates S. mutans gcrR expression as part of a general stress response, and that GcrR acts downstream of SloR to control the ATR.