Immunologic and dose dependent effects of rapamycin and its evolving role in chemoprevention

Rapamycin inhibits the mechanistic (formally mammalian) target of rapamycin (mTOR), an evolutionarily conserved intracellular kinase that influences activation of growth signaling pathways and immune responses to malignancy. Rapamycin has been found to have both immunosuppressant and immunostimulatory effects throughout the innate and adaptive responses based on the inhibition of mTOR signaling. While the immunosuppressant properties of rapamycin and mTOR inhibition explain rapamycin's success in the prevention of transplant rejection, the immunostimulatory characteristics are likely partially responsible for rapamycin's anti-neoplastic effects. The immunologic response to rapamycin is at least partially dependent on the dose and administration schedule, with lower doses inducing immunostimulation and intermittent dosing promoting immune function while limiting metabolic and immunosuppressant toxicities. In addition to its FDA-approved application in advanced malignancies, rapamycin may be effective as a chemopreventive agent, suspending progression of low-grade cancers, preventing invasive conversion of in situ malignancy, or delaying malignant transformation of established pre-malignant conditions.

Multi-institutional, prospective, randomized, double-blind, placebo-controlled phase IIb trial of the tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine to prevent recurrence in high-risk melanoma patients: A subgroup analysis

Background

Checkpoint inhibitors (CPI) in combination with cell‐based vaccines may produce synergistic antitumor immunity. The primary analysis of the randomized and blinded phase IIb trial in resected stage III/IV melanoma demonstrated TLPLDC is safe and improved 24‐month disease‐free survival (DFS) in the per treatment (PT) analysis. Here, we examine efficacy within pre‐specified and exploratory subgroups.

Methods

Stage III/IV patients rendered disease‐free by surgery were randomized 2:1 to TLPLDC vaccine versus placebo. The pre‐specified PT analysis included only patients completing the primary vaccine/placebo series at 6 months. Kaplan–Meier analysis was used to compare 24‐month DFS among subgroups.

Results

There were no clinicopathologic differences between subgroups except stage IV patients were more likely to receive CPI. In stage IV patients, 24‐month DFS was 43% for vaccine versus 0% for placebo (p = 0.098) in the ITT analysis and 73% versus 0% (p = 0.002) in the PT analysis. There was no significant difference in 24‐month DFS when stratified by use of immunotherapy or CPI. For patients with resected recurrent disease, 24‐month DFS was 88.9% versus 33.3% (p = 0.013) in the PT analysis. All benefit from vaccination was in the PT analysis; no benefit was found in patients receiving up to three doses.

Conclusion

The TLPLDC vaccine improved DFS in patients completing the primary vaccine series, particularly in the resected stage IV patients. The efficacy of the TLPLDC vaccine will be confirmed in a phase III study evaluating adjuvant TLPLDC + CPI versus Placebo + CPI in resected stage IV melanoma patients.

A Phase IIb Randomized Controlled Trial of the TLPLDC Vaccine as Adjuvant Therapy After Surgical Resection of Stage III/IV Melanoma: A Primary Analysis

Background

Melanoma therapy has changed dramatically over the last decade with improvements in immunotherapy, yet many patients do not respond to current therapies. This novel vaccine strategy may prime a patient’s immune system against their tumor and work synergistically with immunotherapy against advanced-stage melanoma.

Methods

This was a prospective, randomized, double-blind, placebo-controlled, phase IIb trial of the tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine administered to prevent recurrence in patients with resected stage III/IV melanoma. Patients were enrolled and randomized 2:1 to the TLPLDC vaccine or placebo (empty yeast cell wall particles and autologous dendritic cells). Both intention-to-treat (ITT) and per treatment (PT) analyses were predefined, with PT analysis including patients who remained disease-free through the primary vaccine/placebo series (6 months).

Results

A total of 144 patients were randomized (103 vaccine, 41 control). Therapy was well-tolerated with similar toxicity between treatment arms; one patient in each group experienced related serious adverse events. While disease-free survival (DFS) was not different between groups in ITT analysis, in PT analysis the vaccine group showed improved 24-month DFS (62.9% vs. 34.8%, p = 0.041).

Conclusions

This phase IIb trial of TLPLDC vaccine administered to patients with resected stage III/IV melanoma shows TLPLDC is well-tolerated and improves DFS in patients who complete the primary vaccine series. This suggests patients who do not recur early benefit from TLPLDC in preventing future recurrence from melanoma. A phase III trial of TLPLDC + checkpoint inhibitor versus checkpoint inhibitor alone in patients with advanced, surgically resected melanoma is under development.

Trial Registration

NCT02301611.

Supplementary information

The online version contains supplementary material available at (10.1245/s10434-021-09709-1).

Phase I Trial of Encapsulated Rapamycin in Patients with Prostate Cancer Under Active Surveillance to Prevent Progression

No approved medical therapies prevent progression of low-grade prostate cancer. Rapamycin inhibits cell proliferation and augments immune responses, producing an antitumor effect. Encapsulated rapamycin (eRapa) incorporates rapamycin into a pH-sensitive polymer, ensuring consistent dosing. Here, we present results from a phase I trial evaluating the safety and tolerability of eRapa in patients with prostate cancer. Patients with Gleason ≤7 (3+4) disease (low and intermediate risk) under active surveillance were enrolled in a 3+3 study with three eRapa dosing cohorts (cohort 1, 0.5 mg/week; cohort 2, 1 mg/week; and cohort 3, 0.5 mg/day). Patients were treated for 3 months and followed for an additional 3 months to assess safety, pharmacokinetics, quality of life (QoL), immune response, and disease progression. Fourteen patients (cohort 1, n = 3; cohort 2, n = 3; and cohort 3, n = 8) were enrolled. In cohort 3, one dose-limiting toxicity (DLT; neutropenia) and two non-DLT grade 1-2 adverse events (AE) occurred that resulted in patient withdrawal. All AEs in cohorts 1 and 2 were grade 1. Peak serum rapamycin concentration was 7.1 ng/mL after a 1 mg dose. Stable trough levels (∼2 ng/mL) developed after 48-72 hours. Daily dosing mildly worsened QoL, although QoL recovered after treatment cessation in all categories, except fatigue. Weekly dosing increased naïve T-cell populations. Daily dosing increased central memory cell populations and exhaustion markers. No disease progression was observed. In conclusion, treatment with eRapa was safe and well-tolerated. Daily dosing produced higher frequencies of lower grade toxicities and transient worsening of QoL, while weekly dosing impacted immune response. Future studies will verify clinical benefit and long-term tolerability.Prevention Relevance: There is an unmet medical need for a well-tolerated treatment capable of delaying progression of newly diagnosed low-grade prostate cancer. This treatment would potentially obviate the need for future surgical intervention and improve the perception of active surveillance as a more acceptable option among this patient population.

Chemoprevention in familial adenomatous polyposis: past, present and future

Familial adenomatous polyposis (FAP) is a hereditary colorectal cancer syndrome characterized by colorectal adenomas and a near 100% lifetime risk of colorectal cancer (CRC). Prophylactic colectomy, usually by age 40, is the gold-standard therapy to mitigate this risk. However, colectomy is associated with morbidity and fails to prevent extra-colonic disease manifestations, including gastric polyposis, duodenal polyposis and cancer, thyroid cancer, and desmoid disease. Substantial research has investigated chemoprevention medications in an aim to prevent disease progression, postponing the need for colectomy and temporizing the development of extracolonic disease. An ideal chemoprevention agent should have a biologically plausible mechanism of action, be safe and easily tolerated over a prolonged treatment period, and produce a durable and clinically meaningful effect. To date, no chemoprevention agent tested has fulfilled these criteria. New agents targeting novel pathways in FAP are needed. Substantial preclinical literature exists linking the molecular target of rapamycin (mTOR) pathway to FAP. A single case report of rapamycin, an mTOR inhibitor, used as chemoprevention in FAP patients exists, but no formal clinical studies have been conducted. Here, we review the prior literature on chemoprevention in FAP, discuss the rationale for rapamycin in FAP, and outline a proposed clinical trial testing rapamycin as a chemoprevention agent in patients with FAP.

Correlation of tumor microenvironment from biopsy and resection specimens in untreated colorectal cancer patients: a surprising lack of agreement

Background

Colorectal cancer (CRC) tumor microenvironment (TME) characteristics, such as tumor infiltrating lymphocyte (TIL) densities and PD-L1 status, are predictive of recurrence, disease-free survival, and overall survival. In many malignancies, TME characteristics are also predictive of response to immunotherapy. As window of opportunity studies using neoadjuvant immunotherapy become more common and treatment guidelines incorporate TME features, accurate assessment of the pre-treatment TME using the biopsy specimen is critical. However, no study has thoroughly evaluated the correlation between the TMEs of the biopsy and resection specimens.

Methods

We conducted a retrospective analysis of patients with stage I–III CRC with matched biopsy and resection specimens. CD3+, CD4+, CD8+, and FoxP3+ lymphocyte populations at the center of tumor (CT) and invasive margin (IM) and tumor PD-L1 status in the biopsy and resection specimens were evaluated. TIL populations were compared using Mann–Whitney U tests or Student’s t tests and correlated using Pearson r.

Results

CD3+ and CD4+ densities were significantly higher in the CT of the biopsy relative to the resection specimen Comparing biopsy and resection specimens, no TIL population at either the CT or IM had a correlation coefficient > 0.5. Determining PD-L1 status based on biopsy tissue resulted in a sensitivity of 37.1%, specificity of 81.4%, and accuracy of 61.5%.

Conclusions

These findings demonstrate significant discordance between the TME of the biopsy and resection specimens. Caution should be used when basing treatment decisions on pre-treatment endoscopic biopsy findings and when interpreting changes in the TME between pre-treatment biopsy and resection specimens after neoadjuvant therapy.

Electronic supplementary material

The online version of this article (10.1007/s00262-020-02784-5) contains supplementary material, which is available to authorized users.

Abstract 6537: Impact of disease-free interval on recurrence in high-risk melanoma patients in a phase IIb trial of the tumor lysate particle loaded dendritic cell (TLPLDC) vaccine

Background: Immunotherapy has become a mainstay of adjuvant treatment of advanced melanoma, but recurrence rates remain high. TLPLDC is a personalized vaccine that was shown in a multi-center, double-blind, placebo-controlled phase IIb trial to be safe, well tolerated, and effective for preventing recurrence in patients with resectable stage III or IV melanoma. The trial enrolled patients who had either a new diagnosis of melanoma or recurrent disease. It is hypothesized that the length of disease-free interval (DFI) may be a marker of more indolent disease and therefore a good prognostic factor for vaccine efficacy. In this study, we examined the impact of disease-free interval on response to the vaccination.

Methods: Vaccine production and dosing has been described elsewhere. Patients were characterized as having either primary or recurrent disease at the time of enrollment. For recurrent patients, DFI was defined as the length of time between their initial biopsy establishing a diagnosis of melanoma and complete surgical resection. Patients were grouped by DFI into a primary and recurrent group, where the recurrent group had DFI >3 months and the primary group had no prior disease or recurrence with DFI <3 months. It is thought that a DFI of <3 months more likely represents clinically undetectable metastatic disease that was present at the time of surgical resection. Demographic data was compared using a Chi-square test and survival estimates were calculated by a Kaplan-Meier analysis.

Results: Patients were randomized 2:1 (103 vaccine group, 41 control group) and divided into a recurrent group (n=48) and a primary group (n=96). There was no difference between groups in stage, age, margin status, BRAF mutation, or use of concurrent immunotherapy including checkpoint inhibitors. Patients in the recurrent group had numerically improved 24-month DFS with vaccine vs. placebo (52.6% vs. 23.5%, p=0.214) whereas the primary group had no difference (32.9% vs. 31.8%, p=0.451). Patients in the recurrent group had significantly improved overall survival with vaccine vs. placebo (94.4% vs. 50.5%, p=0.011) whereas the primary group had no difference (83.4% vs. 90.2%, p=0.779).

Conclusions: The TLPLDC vaccine improved overall survival in patients with DFI >3 months prior to recurrence. These patients have more indolent disease biology and a less immunosuppressive tumor microenvironment, where monotherapy with a cancer vaccine is thought to be more effective. Further study is required to identify patients at initial presentation who are more likely to benefit from the TLPLDC vaccine. Meanwhile, combination therapy with vaccine and checkpoint inhibitor may be required for those with more aggressive disease biology.

Citation Format: Robert Connor Chick, Phillip M. Kemp Bohan, Timothy J. Vreeland, Annelies T. Hickerson, Jessica L. Cindass, Diane F. Hale, Guy Travis Clifton, George E. Peoples. Impact of disease-free interval on recurrence in high-risk melanoma patients in a phase IIb trial of the tumor lysate particle loaded dendritic cell (TLPLDC) vaccine [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6537.

Abstract 6536: Safety and efficacy of autologous tumor lysate particle loaded dendritic cell (TLPLDC) vaccination in combination with systemic therapies in patients with metastatic melanoma

Background: The treatment of melanoma has changed drastically with the advent of immunotherapy, particularly checkpoint inhibition (CPI). Unfortunately, only 50-60% of tumors respond to current immunotherapy. The autologous tumor lysate, particle loaded, dendritic cell (TLPLDC) vaccine utilizes the whole antigenic panel of the patient's tumor to stimulate T-cells and may work synergistically with other immunotherapies. We have previously demonstrated both safety and efficacy of TLPLDC vaccine as adjuvant therapy for patients (pts) with resected stage III or IV melanoma who complete the primary vaccine series. Here, we describe results in pts with metastatic melanoma treated with the TLPLDC vaccine together with other approved therapies.

Methods: The TLPLDC vaccine is created by loading autologous tumor lysate into yeast cell wall particles which are then phagocytosed by autologous dendritic cells ex-vivo. Pts who recurred while enrolled in a randomized phase IIb trial of adjuvant TLPLDC vaccine (crossover arm) and pts with metastatic melanoma with measurable disease (MM arm) were offered TLPLDC vaccine in an open-label fashion in addition to other approved therapies as determined by their treating physician. The vaccine is given via intradermal injection monthly x4 followed by boosters at six and nine months. Tumor response is measured by RECIST 1.1 criteria.

Results: To date, 53 pts have been enrolled (28 in the crossover arm and 25 in the MM arm). Within the crossover arm, 18 pts had received TLPLDC as part of the phase IIb trial, 8 were from the placebo group, and 2 patients withdrew prior to vaccination. Within the MM arm, 2 were excluded for no evidence of disease at time of vaccination and 1 withdrew. The vaccine was well tolerated, with 24% of patients experiencing a treatment-related adverse event (AE), with no grade ≥3 AE. Concurrent therapies were varied in the crossover arm, but 36% received CPI, compared with 68% in the MM arm. Of those receiving CPI, 59% had >1 immune-related AE, none of which were grade ≥3. In the crossover arm, 12-month overall survival (OS) was 83.3% in the vaccine-naïve cohort at median follow-up of 6.0 months vs. 94.7% in the re-vaccinated cohort at median follow-up of 9.0 months (p=0.961). In the MM arm, 12-month OS was 61.2% at a median follow-up of 7.7 months. In a pooled analysis of 33 evaluable pts, vaccine-naïve pts (n=21) had a 42.9% non-progression rate compared to a 66.7% non-progression rate in re-vaccinated pts (n=12).

Conclusion: Vaccination with the TLPLDC vaccine in combination with approved systemic therapies in MM pts is well tolerated, with acceptable rates of immune-related AE when combined with CPI. Additionally, vaccination, and specifically re-vaccination, may provide clinical benefit particularly if used in combination with other approved therapies.

Citation Format: Robert Connor Chick, Annelies T. Hickerson, Guy Travis Clifton, Phillip M. Kemp Bohan, Tommy A. Brown, Jessica L. Cindass, John W. Myers, Timothy J. Vreeland, Doreen O. Jackson, Diane F. Hale, Kaitlin M. Peace, Garth S. Herbert, Xianzhong Yu, Thomas Wagner, George E. Peoples. Safety and efficacy of autologous tumor lysate particle loaded dendritic cell (TLPLDC) vaccination in combination with systemic therapies in patients with metastatic melanoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6536.

Multi-institutional, prospective, randomized, double-blind, placebo-controlled phase IIb trial of the tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine to prevent recurrence in high-risk melanoma patients: A subgroup analysis

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Background: A novel vaccine strategy may prevent recurrence in high-risk melanoma patients (pts). The TLPLDC vaccine uses yeast cell wall particles (YCWP) to load tumor lysate into autologous dendritic cells (DC). In this phase IIb trial of TLPLDC vs. placebo in resected stage III/IV pts, TLPLDC increased 24 month (mo) disease free survival (DFS) in the per treatment (PT) population. Here, we present a 24mo DFS subgroup analysis and estimated overall 36mo DFS. Methods: Disease-free pts were randomized 2:1 to the TLPLDC vaccine vs. unloaded YCWP+DC at 0, 1, 2, 6, 12, and 18mo. The protocol was amended to allow concurrent adjuvant checkpoint inhibitor (CPI) therapy once approved. The pre-specified PT population included only pts completing the primary vaccine/placebo series (PVS) at 6 mo. Kaplan-Meier estimates of DFS were used to compare treatment arms by stage (III or IV) and CPI therapy (yes/no) in the ITT and PT populations. Results: 144 pts were randomized (103 TLPLDC, 41 placebo); 98 pts (66 TLPLDC, 32 placebo) completed the PVS. There were no clinicopathologic differences between treatment groups. There was no difference in 24mo DFS in stage III pts (n = 112), but in stage IV pts (n = 32), the 24mo DFS was 44% vs 0% (TLPLDC vs placebo) (p = 0.41) in ITT and 73.3% vs. 0% (HR 0.14, p = 0.002) in PT. Stage IV pts were more likely to receive CPI than stage III pts (50% vs. 30%, p = 0.003). There was no difference in 24mo DFS for pts who did not receive CPI (n = 102), but in pts who received CPI (n = 42), the 24mo DFS was 49.3% vs. 31.3% (p = 0.71) in ITT and 68.8% vs. 41.7% (HR 0.46, p = 0.28) in PT, showing a trend toward improved DFS in pts who completed the PVS and received CPI (n = 31). Overall, the 36mo estimated DFS was 34.2% vs. 21.6% (p = 0.89) for ITT and 56.9% vs. 27.9% (p = 0.021) for PT. Conclusions: The TLPLDC vaccine improved DFS in patients completing the PVS at 24 and 36 mos, particularly in the resected stage IV subset. The apparent synergistic effect with TLPLDC + CPI will be confirmed in a phase III study evaluating adjuvant TLPLDC + CPI vs. CPI alone in resected stage IV melanoma pts. Clinical trial information: NCT02301611.

Results of a phase Ib trial of encapsulated rapamycin in prostate cancer patients under active surveillance to prevent progression

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Background: At low doses, rapamycin inhibits cell proliferation and angiogenesis while augmenting CD8 T-cell responses, cumulatively producing an antitumor effect. Oral rapamycin is limited by variable bioavailability. Encapsulated rapamycin (eRapa) incorporates submicron rapamycin particles into a pH-sensitive polymer, improving bioavailability and allowing for consistent and lower dosing. Here, we present results of a phase Ib trial evaluating safety and treatment effects of eRapa in patients with low-grade prostate cancer (PCa). Methods: PCa patients with Gleason ≤7 (3+4) under active surveillance were enrolled in a 3+3 study with 3 dosing cohorts (0.5mg weekly, 1mg weekly, and 0.5mg daily) to determine the optimal dosing. Patients were treated for 3 months (m) and followed for 6m. Safety, labs (including PSA), pharmacokinetics, immune response, and quality of life (QOL) were assessed for each cohort. Results: 14 patients were enrolled; 3 in cohort 1, 3 in cohort 2, and 8 in cohort 3. 2 patients withdrew for non-dose limiting toxicity (DLT) (grade 1-2) adverse events (AEs) in cohort 3, leaving 6 evaluable. A single grade 3 DLT (neutropenia) occurred in cohort 3. No AEs > Grade 1 occurred in cohorts 1/2. Peak serum rapamycin concentration ([Rapa]) was 7 ng/mL after a 1 mg dose (2h after administration). Stable trough levels (2 ng/mL) were established after 48 hrs and persisted to 13wks. Central memory CD8 T cells and CD3+/CD56+ NK cells were more prevalent in cohort 3 than other cohorts at 1m (p = 0.027 and p = 0.041) and 3m (p = 0.023 and p = 0.049). There was no significant change in PSA level; no patients clinically progressed on therapy. In cohort 3, there were no differences between baseline and 3m QOL assessments but there was a suggestion of withdrawal effects at 6m. Conclusions: Treatment with low dose eRapa is safe and well-tolerated. The dose of 0.5mg daily produced stable serum [Rapa] through the duration of treatment and resulted in a positive immune impact. Further investigation with low dose and/or intermittent dosing of eRapa as a preventive agent in PCa and other indications will be required to establish clinical benefit. Clinical trial information: NCT03618355.

Abstract CT208: Prior vaccination with the autologous Tumor Lysate Particle Loaded Dendritic Cell (TLPLDC) Vaccine may impact clinical outcomes in melanoma patients treated with systemic therapies and re-vaccination

Background: Melanoma is an immunogenic cancer, yet only 50-60% of tumors respond to current immunotherapy. The autologous tumor lysate, particle loaded, dendritic cell (TLPLDC) vaccine may potentiate an immune response by stimulating T-cells. We are conducting a phase IIb double-blinded randomized trial of TLPLDC to prevent recurrence after resection. Patients who recurred were offered enrollment in an open-label TLPLDC vaccine trial along with standard therapy. Here, we describe characteristics and clinical outcomes of recurred patients that continued on open label TLPLDC vaccination.

Methods: Patients with resected no evidence of disease (NED) stage III/IV melanoma were randomized to TLPLDC vs. empty yeast cell wall particle (YCWP) loaded DC in a 2:1 fashion. TLPDC is created by loading autologous tumor lysate into YCWP. This is then introduced ex vivo to the patient’s DC for phagocytosis. 1-1.5x106TLPLDCs are given via intradermal injection monthly x4 followed by boosters at 6 and 9 months. Patients who recurred after receiving TLPLDC (vaccine group, VG) or after empty YCWP (control group, CG) on the trial (primary endpoint) were offered open label TLPLDC vaccination with same dosing schedule along with standard therapy as determined by the patient’s treatment team. Disease status is measured by RECIST criteria.

Results: To date, 23 (14 VG and 11 CG) patients have enrolled and been vaccinated, with median follow up (fu) of 7.86 months (mo). The patients received the following additional therapies: surgery, gamma-knife, check point inhibitor, radiation, TVEC, BRAF/MEK, and imantinib. No related toxicities > grade 2 were observed. Of 14 VG patients, 5 were NED when re-enrolled, 9 had measurable disease (MD). Of these, 11 have followed up data, 9 (82%) show disease control (5/5 NED patients remain NED, 4/6 with MD show SD), while 2 (18%) have progressed. Of 9 CG patients, 4 were NED and 5 had measurable disease at time of re-enrollment. Of these, 8 have followed up, 5 (62%) show disease control (2/4 NED remain NED, 1/4 with MD shows regression, 2/4 SD), while 3 (38%) have progressed (2/4 NED, 1/3 with MD).

Conclusion: Open label administration of TLPLPDC vaccine after recurrence is demonstrated as a safe therapy and shows potential clinical benefit when combined SOC therapy. Further study is warranted to determine if prior exposure to TLPLDC may provide clinical benefit after the first episode of disease recurrence.

Citation Format: Annelies T. Hickerson, Guy T. Clifton, Tommy A. Brown, Jessica L. Cindass, John W. Myers, Timothy J. Vreeland, Diane F. Hale, Kaitlin M. Peace, Doreen O. Jackson, Garth Herbert, Xianzhong Yu, Thomas E. Wagner, George E. Peoples. Prior vaccination with the autologous Tumor Lysate Particle Loaded Dendritic Cell (TLPLDC) Vaccine may impact clinical outcomes in melanoma patients treated with systemic therapies and re-vaccination [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT208.