Neoadjuvant nivolumab plus chemotherapy followed by resection for superior sulcus tumour with high PD-L1 expression: A case report

The standard treatment for resectable non-small cell lung cancer (NSCLC) located in the superior sulcus is neoadjuvant chemoradiotherapy followed by highly invasive resection. Based on the results of the CheckMate 816 trial, which showed a marked improvement in the efficacy of neoadjuvant chemo-immunotherapy, we report a case of minimally invasive resection after neoadjuvant nivolumab plus chemotherapy for superior sulcus NSCLC, resulting in a pathologic complete response. The patient was a 76-year-old man with a 65-mm right superior sulcus tumour diagnosed as squamous cell carcinoma with 95% PD-L1. After two courses of neoadjuvant nivolumab plus chemotherapy, the tumour was completely resected through an 11-cm right lateral thoracotomy with second rib resection and first rib preservation. No residual tumour cells were observed in the specimen, and the patient had a pathologic complete response. This report represents a new treatment option for superior sulcus tumours.

PRMT5 is an actionable therapeutic target in CDK4/6 inhibitor-resistant ER+/RB-deficient breast cancer

CDK4/6 inhibitors (CDK4/6i) have improved survival of patients with estrogen receptor-positive (ER+) breast cancer. However, patients treated with CDK4/6i eventually develop drug resistance and progress. RB1 loss-of-function alterations confer resistance to CDK4/6i, but the optimal therapy for these patients is unclear. Through a genome-wide CRISPR screen, we identify protein arginine methyltransferase 5 (PRMT5) as a molecular vulnerability in ER+/RB1-knockout breast cancer cells. Inhibition of PRMT5 blocks the G1-to-S transition in the cell cycle independent of RB, leading to growth arrest in RB1-knockout cells. Proteomics analysis uncovers fused in sarcoma (FUS) as a downstream effector of PRMT5. Inhibition of PRMT5 results in dissociation of FUS from RNA polymerase II, leading to hyperphosphorylation of serine 2 in RNA polymerase II, intron retention, and subsequent downregulation of proteins involved in DNA synthesis. Furthermore, treatment with the PRMT5 inhibitor pemrametostat and a selective ER degrader fulvestrant synergistically inhibits growth of ER+/RB-deficient cell-derived and patient-derived xenografts. These findings highlight dual ER and PRMT5 blockade as a potential therapeutic strategy to overcome resistance to CDK4/6i in ER+/RB-deficient breast cancer.

A Phase II Study of High-Flow Nasal Cannula for Relieving Dyspnea in Advanced Cancer Patients

CONTEXT

The efficacy and tolerability of high-flow nasal cannula (HFNC) for relieving dyspnea in advanced cancer patients with limited prognosis requires elucidation.

OBJECTIVES

The primary aim of this trial was to assess the efficacy and tolerability of HFNC regarding dyspnea including severe as well as moderate for longer durations in patients under palliative care.

METHODS

In this prospective study, hospitalized patients with advanced cancer who had dyspnea at rest (numeric rating scale, NRS≥3) and hypoxemia were enrolled. They were treated with HFNC for five days in the respiratory unit. Primary endpoint was mean change of modified Borg scale at 24 hours. Key secondary endpoints consisted of mean changes in modified Borg scale during the study period and feasibility (Trial Identifier, UMIN000035738).

RESULTS

Between February 2019 and February 2022, 25 patients were enrolled and 21 were analyzed. Twenty patients used inspired oxygen and the mean fraction of inspired oxygen (FiO2) was 0.34 (range, 0.21-1.0). At baseline, mean NRS (dyspnea) was 5.9 (range, 3-10). Median survival time was 19 days (range, 3-657). The mean change of modified Borg scale was 1.4 (80% confidence interval [CI]: 0.8-1.9) at 24 hours, 12 patients (57%) showed 1.0 points improvement of modified Borg scale. Within two hours, 15 patients showed 1.0 points improvement of modified Borg scale and such early responders were likely to maintain dyspnea improvement for 24 hours. Nineteen patients could continue HFNC for 24 hours and 11 patients completed five days of HFNC.

CONCLUSION

To our knowledge, this trial is the first prospective study to assess the five-day efficacy and tolerability of HFNC for dyspnea in patients under palliative care. Although this did not reach the prespecified endpoint, about half of the patients showed 1.0 point improvement, a minimally clinically important difference (MCID) in the chronic lung disease. HFNC can be a palliative treatment option in advanced cancer patients with dyspnea.

Machine learning analysis of pathological images to predict 1-year progression-free survival of immunotherapy in patients with small-cell lung cancer

BACKGROUND

In small-cell lung cancer (SCLC), the tumor immune microenvironment (TIME) could be a promising biomarker for immunotherapy, but objectively evaluating TIME remains challenging. Hence, we aimed to develop a predictive biomarker of immunotherapy efficacy through a machine learning analysis of the TIME.

METHODS

We conducted a biomarker analysis in a prospective study of patients with extensive-stage SCLC who received chemoimmunotherapy as the first-line treatment. We trained a model to predict 1-year progression-free survival (PFS) using pathological images (H&E, programmed cell death-ligand 1 (PD-L1), and double immunohistochemical assay (cluster of differentiation 8 (CD8) and forkhead box P3 (FoxP3)) and patient information. The primary outcome was the mean area under the curve (AUC) of machine learning models in predicting the 1-year PFS.

RESULTS

We analyzed 100,544 patches of pathological images from 78 patients. The mean AUC values of patient information, pathological image, and combined models were 0.789 (range 0.571-0.982), 0.782 (range 0.750-0.911), and 0.868 (range 0.786-0.929), respectively. The PFS was longer in the high efficacy group than in the low efficacy group in all three models (patient information model, HR 0.468, 95% CI 0.287 to 0.762; pathological image model, HR 0.334, 95% CI 0.117 to 0.628; combined model, HR 0.353, 95% CI 0.195 to 0.637). The machine learning analysis of the TIME had better accuracy than the human count evaluations (AUC of human count, CD8-positive lymphocyte: 0.681, FoxP3-positive lymphocytes: 0.626, PD-L1 score: 0.567).

CONCLUSIONS

The spatial analysis of the TIME using machine learning predicted the immunotherapy efficacy in patients with SCLC, thus supporting its role as an immunotherapy biomarker.

Mannitol versus furosemide in patients with thoracic malignancies who received cisplatin-based chemotherapy using short hydration: A randomized phase II trial

BACKGROUND

Mannitol is exclusively recommended in the National Comprehensive Cancer Network guidelines for diuresis in cisplatin (CDDP)-based chemotherapy. The utility of furosemide, a widely used and convenient diuretic, thus requires clarification.

METHODS

This is a prospective, single-centered, open-label, noninferiority phase II study. Patients with thoracic malignancies who planned to receive CDDP-based chemotherapy were randomly assigned to receive either mannitol (arm A) or furosemide (arm B). The primary end point was set as the proportion of patients who experienced any grade of "creatinine (Cr) increased" based on the upper limit of the normal range (ULN) during the first cycle as assessed by Common Terminology Criteria for Adverse Events Version 4.0. Secondary end points were Cr increased based on the baseline value during the first cycle, Cr increased after the completion of CDDP, and the proportion of patients with phlebitis.

RESULTS

Between April 2018 and March 2022, 115 patients were enrolled and 106 were analyzed. Any grade of Cr increased based on the ULN during the first cycle was 17.3% (arm A) and 24.1% (arm B), respectively (p = 0.34). Therefore, the primary end point was not met. After completion of chemotherapy, any grade of Cr increased was observed in 23.1% (arm A) and 31.5% (arm B), respectively. However, the actual serum Cr level and Cr clearance during the courses were not different between the arms. Phlebitis occurred more frequently in arm A (28.8%) than arm B (16.7%).

CONCLUSIONS

Mannitol should remain the standard diuresis in CDDP-based chemotherapy assessed by conventional CTCAE grading, but furosemide can be room for consideration when assessed by actual serum Cr level and Cr clearance.

NOTCH1 and CREBBP co-mutations negatively affect the benefit of adjuvant therapy in completely resected EGFR-mutated NSCLC: translational research of phase III IMPACT study

The phase III IMPACT study (UMIN000044738) compared adjuvant gefitinib with cisplatin plus vinorelbine (cis/vin) in completely resected epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC). Although the primary endpoint of disease-free survival (DFS) was not met, we searched for molecular predictors of adjuvant gefitinib efficacy. Of 234 patients enrolled in the IMPACT study, 202 patients were analyzed for 409 cancer-related gene mutations and tumor mutation burden using resected lung cancer specimens. Frequent somatic mutations included tumor protein p53 (TP53; 58.4%), CUB and Sushi multiple domains 3 (CSMD3; 11.8%), and NOTCH1 (9.9%). Multivariate analysis showed that NOTCH1 co-mutation was a significant poor prognostic factor for overall survival (OS) in the gefitinib group and cAMP response element binding protein (CREBBP) co-mutation for DFS and OS in the cis/vin group. In patients with NOTCH1 co-mutations, gefitinib group had a shorter OS than cis/vin group (Hazard ratio 5.49, 95% CI 1.07-28.00), with a significant interaction (P for interaction = 0.039). In patients with CREBBP co-mutations, the gefitinib group had a longer DFS than the cis/vin group, with a significant interaction (P for interaction = 0.058). In completely resected EGFR-mutated NSCLC, NOTCH1 and CREBBP mutations might predict poor outcome in patients treated with gefitinib and cis/vin, respectively.

Biomarker Testing in Patients With Unresectable Advanced or Recurrent Non-Small Cell Lung Cancer

Importance

Biomarker testing for driver mutations is essential for selecting appropriate non-small cell lung cancer (NSCLC) treatment but is insufficient.

Objective

To investigate the status of biomarker testing and drug therapy for NSCLC in Japan for identifying problems in treatment.

Design, Setting, and Participants

The REVEAL cohort study included retrospective data collection and prospective follow-up from 29 institutions across Japan. Of 1500 patients diagnosed with advanced or recurrent NSCLC between January 1 and March 18, 2021, 1479 were eligible. Cases recognized at the wrong clinical stage (n = 12), diagnosed outside the study period (n = 6), not treated according to eligibility criteria before recurrence (n = 2), and with deficient consent acquisition procedure (n = 1) were excluded.

Main Outcomes and Measures

The primary end point was the biomarker testing status. Treatment-related factors were examined.

Results

Among the 1479 patients included in the analysis, the median age was 72 (range, 30-95) years; 1013 (68.5%) were men; 1161 (78.5%) had an Eastern Cooperative Oncology Group performance status 0 or 1; 1097 (74.2%) were current or past smokers; and 947 (64.0%) had adenocarcinoma. Biomarker status was confirmed in 1273 patients (86.1%). Multigene testing was performed in 705 cases (47.7%); single-gene testing, in 847 (57.3%); and both, in 279 (18.9%). Biomarker testing was performed for EGFR in 1245 cases (84.2%); ALK, in 1165 (78.8%); ROS1, in 1077 (72.8%); BRAF, in 803 (54.3%); and MET, in 805 (54.4%). Positivity rates among 898 adenocarcinoma cases included 305 (34.0%) for EGFR, 29 (3.2%) for ALK, 19 (2.1%) for ROS1, 11 (1.2%) for BRAF, and 14 (1.6%) for MET. Positivity rates among 375 nonadenocarcinoma cases were 14 (3.7%) for EGFR, 6 (1.6%) for ALK, 1 (0.3%) for ROS1, 3 (0.8%) for BRAF, and 8 (2.1%) for MET. Poor physical status, squamous cell carcinoma, and other comorbidities were associated with hampered multigene testing. Targeted therapy was received as first-line treatment by 263 of 278 cases (94.6%) positive for EGFR, 25 of 32 (78.1%) positive for ALK, 15 of 24 (62.5%) positive for ROS1, 9 of 12 (75.0%) positive for BRAF, and 12 of 19 (63.2%) positive for MET. Median overall survival of patients with positive findings for driver gene alteration and who received targeted therapy was 24.3 (95% CI, not reported) months; with positive findings for driver gene alteration and who did not receive targeted therapy, 15.2 (95% CI, 7.7 to not reported) months; and with negative findings for driver gene alteration, 11.0 (95% CI, 10.0-12.5) months. Multigene testing for nonadenocarcinomas and adenocarcinomas accounted for 705 (47.7%) of all NSCLC cases.

Conclusions and Relevance

These findings suggest that multigene testing has not been sufficiently implemented in Japan and should be considered prospectively, even in nonadenocarcinomas, to avoid missing rare driver gene alterations.

Tarlatamab for Patients with Previously Treated Small-Cell Lung Cancer

BACKGROUND

Tarlatamab, a bispecific T-cell engager immunotherapy targeting delta-like ligand 3 and CD3, showed promising antitumor activity in a phase 1 trial in patients with previously treated small-cell lung cancer.

METHODS

In this phase 2 trial, we evaluated the antitumor activity and safety of tarlatamab, administered intravenously every 2 weeks at a dose of 10 mg or 100 mg, in patients with previously treated small-cell lung cancer. The primary end point was objective response (complete or partial response), as assessed by blinded independent central review according to the Response Evaluation Criteria in Solid Tumors, version 1.1.

RESULTS

Overall, 220 patients received tarlatamab; patients had previously received a median of two lines of treatment. Among patients evaluated for antitumor activity and survival, the median follow-up was 10.6 months in the 10-mg group and 10.3 months in the 100-mg group. An objective response occurred in 40% (97.5% confidence interval [CI], 29 to 52) of the patients in the 10-mg group and in 32% (97.5% CI, 21 to 44) of those in the 100-mg group. Among patients with an objective response, the duration of response was at least 6 months in 59% (40 of 68 patients). Objective responses at the time of data cutoff were ongoing in 22 of 40 patients (55%) in the 10-mg group and in 16 of 28 patients (57%) in the 100-mg group. The median progression-free survival was 4.9 months (95% CI, 2.9 to 6.7) in the 10-mg group and 3.9 months (95% CI, 2.6 to 4.4) in the 100-mg group; the estimates of overall survival at 9 months were 68% and 66% of patients, respectively. The most common adverse events were cytokine-release syndrome (in 51% of the patients in the 10-mg group and in 61% of those in the 100-mg group), decreased appetite (in 29% and 44%, respectively), and pyrexia (in 35% and 33%). Cytokine-release syndrome occurred primarily during treatment cycle 1, and events in most of the patients were grade 1 or 2 in severity. Grade 3 cytokine-release syndrome occurred less frequently in the 10-mg group (in 1% of the patients) than in the 100-mg group (in 6%). A low percentage of patients (3%) discontinued tarlatamab because of treatment-related adverse events.

CONCLUSIONS

Tarlatamab, administered as a 10-mg dose every 2 weeks, showed antitumor activity with durable objective responses and promising survival outcomes in patients with previously treated small-cell lung cancer. No new safety signals were identified. (Funded by Amgen; DeLLphi-301 ClinicalTrials.gov number, NCT05060016.).

Perioperative Durvalumab for Resectable Non-Small-Cell Lung Cancer

BACKGROUND

Neoadjuvant or adjuvant immunotherapy can improve outcomes in patients with resectable non-small-cell lung cancer (NSCLC). Perioperative regimens may combine benefits of both to improve long-term outcomes.

METHODS

We randomly assigned patients with resectable NSCLC (stage II to IIIB [N2 node stage] according to the eighth edition of the AJCC Cancer Staging Manual) to receive platinum-based chemotherapy plus durvalumab or placebo administered intravenously every 3 weeks for 4 cycles before surgery, followed by adjuvant durvalumab or placebo intravenously every 4 weeks for 12 cycles. Randomization was stratified according to disease stage (II or III) and programmed death ligand 1 (PD-L1) expression (≥1% or <1%). Primary end points were event-free survival (defined as the time to the earliest occurrence of progressive disease that precluded surgery or prevented completion of surgery, disease recurrence [assessed in a blinded fashion by independent central review], or death from any cause) and pathological complete response (evaluated centrally).

RESULTS

A total of 802 patients were randomly assigned to receive durvalumab (400 patients) or placebo (402 patients). The duration of event-free survival was significantly longer with durvalumab than with placebo; the stratified hazard ratio for disease progression, recurrence, or death was 0.68 (95% confidence interval [CI], 0.53 to 0.88; P = 0.004) at the first interim analysis. At the 12-month landmark analysis, event-free survival was observed in 73.4% of the patients who received durvalumab (95% CI, 67.9 to 78.1), as compared with 64.5% of the patients who received placebo (95% CI, 58.8 to 69.6). The incidence of pathological complete response was significantly greater with durvalumab than with placebo (17.2% vs. 4.3% at the final analysis; difference, 13.0 percentage points; 95% CI, 8.7 to 17.6; P<0.001 at interim analysis of data from 402 patients). Event-free survival and pathological complete response benefit were observed regardless of stage and PD-L1 expression. Adverse events of maximum grade 3 or 4 occurred in 42.4% of patients with durvalumab and in 43.2% with placebo. Data from 62 patients with documented EGFR or ALK alterations were excluded from the efficacy analyses in the modified intention-to-treat population.

CONCLUSIONS

In patients with resectable NSCLC, perioperative durvalumab plus neoadjuvant chemotherapy was associated with significantly greater event-free survival and pathological complete response than neoadjuvant chemotherapy alone, with a safety profile that was consistent with the individual agents. (Funded by AstraZeneca; AEGEAN ClinicalTrials.gov number, NCT03800134.).

Study Design and Rationale for Marble Study: A Phase II Trial of Atezolizumab (MPDL3280A) Plus Carboplatin and Paclitaxel in Patients With Advanced or Recurrent Thymic Carcinoma (JTD2101)

BACKGROUND

Thymic carcinoma (TC) is a rare thymic epithelial tumor, and advanced or recurrent TC has limited prognosis. Treatment for chemotherapy-naïve, advanced, or recurrent TC remains unchanged with the combination of carboplatin and paclitaxel; therefore, a new treatment strategy is warranted. Immune checkpoint blockades inhibiting the programmed cell death-1 (PD-1) pathway (PD-1 and its ligand, PD-L1) have shown potential as a monotherapy for TC, although the efficacy of monotherapy was moderate for previously treated TC. We hypothesized that the combination of an anti-PD-L1 antibody, atezolizumab, with carboplatin and paclitaxel, would be effective in inducing immunogenic cell death in patients with advanced or recurrent TC.

METHODS

We initiated a multicenter, single-arm, open-label phase II study of atezolizumab combined with carboplatin and paclitaxel for metastatic or recurrent TC. Eligible patients will receive atezolizumab plus carboplatin and paclitaxel every 3 weeks for up to 6 cycles, followed by atezolizumab every 3 weeks for up to 2 years until progression or unacceptable toxicity. A total of 47 patients will be enrolled in this study, with a 24-month enrollment period and 12-month follow-up. The primary endpoint is the objective response rate (ORR), based on an independent central review. The secondary endpoints are the investigator-assessed ORR, disease control rate, progression-free survival, duration of response, overall survival, and safety.

RESULTS

This study aims to establish the safety and efficacy of atezolizumab combined with carboplatin and paclitaxel in patients with advanced or recurrent TC.

TRIAL REGISTRATION

Japan Registry of Clinical Trials (jRCT), jRCT2031220144. Registered on June 18, 2022, https://jrct.niph.go.jp/en-latest-detail/jRCT2031220144.

Randomized, open-label phase II study of brigatinib and carboplatin plus pemetrexed and brigatinib alone for chemotherapy-naive patients with ALK-rearranged non-squamous non-small cell lung cancer: treatment rationale and protocol design of the B-DASH study (WJOG 14720 L)

BACKGROUND

The ALTA-1L study compared brigatinib with crizotinib in untreated ALK-rearranged non-small cell lung cancer (NSCLC) patients, demonstrating the efficacy of brigatinib. Although the median progression-free survival (PFS) of brigatinib group was 24.0 months, the one-year PFS rate was 70%. In the NEJ009 study, patients with EGFR mutations showed improved outcomes with gefitinib plus chemotherapy compared with gefitinib monotherapy. To evaluate the efficacy of the combination of brigatinib with chemotherapy for patients with ALK-rearranged NSCLC, we designed B-DASH study (WJOG 14720L).

METHODS

B-DASH study is a multicenter, two-arm, phase II study. Eligible patients have untreated stage IIIB, stage IIIC, stage IV, or postoperative relapse ALK-rearranged nonsquamous NSCLC. Patients will be randomized in a 1:1 ratio to receive brigatinib (180 mg once daily with a 7-day lead-in period at 90 mg) monotherapy or carboplatin (area under the curve = 5 on day 1) plus pemetrexed (500 mg/m2 on day 1) and brigatinib in a 3-week cycle for up to four cycles, followed by pemetrexed and brigatinib as maintenance therapy. The target hazard ratio of 0.62 is set based on the NEJ009 study. With one-sided alpha = 0.20 and power = 0.8, the sample size for the B-DASH study was calculated to be 110, considering the possibility of patients dropping out. The primary endpoint is PFS. The key secondary endpoints are the overall response rate and overall survival. We will evaluate tumor-derived DNA from plasma specimens before treatment, 42 days after administering the study drug, and on the day of progressive disease. Recruitment began in November 2021 and is ongoing.

DISCUSSION

The efficacy of combination therapy with tyrosine kinase inhibitors and cytotoxic chemotherapy was demonstrated in patients with EGFR mutations but remains unclear in patients with ALK-rearranged NSCLC. The B-DASH study is the only trial of brigatinib combined with chemotherapy in patients with untreated ALK-rearranged NSCLC.

TRIAL REGISTRATION

jRCT identifier: jRCTs041210103.

Acquired Secondary HER2 Mutations Enhance HER2/MAPK Signaling and Promote Resistance to HER2 Kinase Inhibition in Breast Cancer

HER2 mutations drive the growth of a subset of breast cancers and are targeted with HER2 tyrosine kinase inhibitors (TKI) such as neratinib. However, acquired resistance is common and limits the durability of clinical responses. Most HER2-mutant breast cancers progressing on neratinib-based therapy acquire secondary mutations in HER2. It is unknown whether these secondary HER2 mutations, other than the HER2T798I gatekeeper mutation, are causal to neratinib resistance. Herein, we show that secondary acquired HER2T862A and HER2L755S mutations promote resistance to HER2 TKIs via enhanced HER2 activation and impaired neratinib binding. While cells expressing each acquired HER2 mutation alone were sensitive to neratinib, expression of acquired double mutations enhanced HER2 signaling and reduced neratinib sensitivity. Computational structural modeling suggested that secondary HER2 mutations stabilize the HER2 active state and reduce neratinib binding affinity. Cells expressing double HER2 mutations exhibited resistance to most HER2 TKIs but retained sensitivity to mobocertinib and poziotinib. Double-mutant cells showed enhanced MEK/ERK signaling, which was blocked by combined inhibition of HER2 and MEK. Together, these findings reveal the driver function of secondary HER2 mutations in resistance to HER2 inhibition and provide a potential treatment strategy to overcome acquired resistance to HER2 TKIs in HER2-mutant breast cancer.

SIGNIFICANCE

HER2-mutant breast cancers acquire secondary HER2 mutations that drive resistance to HER2 tyrosine kinase inhibitors, which can be overcome by combined inhibition of HER2 and MEK.

First-line nivolumab, paclitaxel, carboplatin, and bevacizumab for advanced non-squamous non-small cell lung cancer: Updated survival analysis of the ONO-4538-52/TASUKI-52 randomized controlled trial

BACKGROUND

ONO-4538-52/TASUKI-52 was performed in Japan, Korea, and Taiwan to determine the oncological effectiveness and safety of combining nivolumab or placebo with bevacizumab plus platinum chemotherapy for the initial (first-line) treatment of patients with advanced non-squamous non-small cell lung cancer (nsNSCLC). At the interim analysis (minimum follow-up, 7.4 months), the independent radiology review committee-assessed progression-free survival was significantly longer in the nivolumab arm, but overall survival (OS) data were immature.

METHODS

Here, we present the updated OS data. Patients with treatment-naïve stage IIIB/IV or recurrent nsNSCLC without driver mutations in ALK, EGFR, or ROS1, were randomized 1:1 to receive either nivolumab or placebo. Patients in both arms received paclitaxel, carboplatin, and bevacizumab, administered 3-weekly for a maximum of 6 cycles. Nivolumab/placebo and bevacizumab were subsequently continued until disease progression or unacceptable toxicity.

RESULTS

Overall, 550 patients were randomized. At the time of the analysis (minimum follow-up: 19.4 months), the median OS was longer in the nivolumab arm than in the placebo arm (30.8 vs. 24.7 months; hazard ratio 0.74, 95% confidence interval 0.58-0.94). The 12-month OS rates were 81.3% vs. 76.3% in the nivolumab vs. placebo arms, respectively. The respective 18-month OS rates were 69.0% vs. 61.9%.

CONCLUSION

Nivolumab plus platinum chemotherapy and bevacizumab demonstrated longer OS vs. the placebo combination. We believe this regimen is viable as a standard, first-line treatment for patients with advanced nsNSCLC without driver mutations in ALK, EGFR, or ROS1.

Protein arginine methyltransferase 5 (PRMT5) is an actionable therapeutic target in CDK4/6 inhibitor-resistant ER+/RB-deficient breast cancer

CDK4/6 inhibitors (CDK4/6i) have improved survival of patients with estrogen receptor-positive (ER+) breast cancer. However, patients treated with CDK4/6i eventually develop drug resistance and progress. RB1 loss-of-function alterations confer acquired resistance to CDK4/6i, but the optimal therapy for these patients is unclear. Using a genome-wide CRISPR screen, we identified protein arginine methyltransferase 5 (PRMT5) as a molecular vulnerability in ER+/RB1-knockout (RBKO) breast cancer cells. PRMT5 inhibition blocked cell cycle G1-to-S transition independent of RB, thus arresting growth of RBKO cells. Proteomics analysis uncovered fused in sarcoma (FUS) as a downstream effector of PRMT5. Pharmacological inhibition of PRMT5 resulted in dissociation of FUS from RNA polymerase II (Pol II), Ser2 Pol II hyperphosphorylation, and intron retention in genes that promote DNA synthesis. Treatment with the PRMT5i inhibitor pemrametostat and fulvestrant synergistically inhibited growth of ER+/RB-deficient patient-derived xenografts, suggesting dual ER and PRMT5 blockade as a novel therapeutic strategy to treat ER+/RB-deficient breast cancer.

Carboplatin and irinotecan (CI) vs. carboplatin and etoposide (CE) for the treatment of extended-stage small-cell lung cancer in an elderly population: A phase II/III randomized control trial

OBJECTIVES

Cisplatin plus irinotecan has been considered as the standard therapy in younger (<70 years old) patients for extensive-disease small-cell lung cancer (ED-SCLC) in Japan. However, there is a lack of high-quality evidence for the use of irinotecan in elderly patients with ED-SCLC. This study aimed to demonstrate that carboplatin plus irinotecan (CI) improves overall survival (OS) in elderly patients with ED-SCLC.

MATERIALS AND METHODS

This was a randomized Phase II/III trial which enrolled elderly patients with ED-SCLC. Patients were randomized to the CI or carboplatin plus etoposide (CE) arm in a 1:1 ratio. The CE group intravenously received carboplatin (AUC 5 mg/ml/min on day 1) and etoposide (80 mg/m2 on days 1-3) every 3 weeks for four cycles. The CI group received carboplatin (AUC 4 mg/ml/min on day 1) and irinotecan (50 mg/m2 on days 1 and 8) intravenously every 3 weeks for 4 cycles.

RESULTS

In total, 258 patients were enrolled and randomized (CE arm, 129 patients; CI arm, 129 patients). The median overall survival, progression-free survival, and objective response rate of the CE vs. CI arms were 12.0 (95% CI, 9.3-13.7) vs. 13.2 (95% CI, 11.1-14.6) months (HR, 0.85 (95% CI, 0.65-1.11)) (one-sided P = 0.11), 4.4 (95% CI, 4.0-4.7) vs. 4.9 (95% CI, 4.5-5.2) months (HR, 0.85 (95% CI, 0.66-1.09)), and 59.5% vs. 63.2%, respectively. A higher incidence of myelosuppression was observed in the CE group, whereas a higher incidence of gastrointestinal toxicity was observed in the CI group. Three treatment-related deaths occurred (one due to lung infection in the CE arm, and one due to lung infection and sepsis each in the CI arm).

CONCLUSIONS

The CI treatment showed favorable efficacy; however, the difference was not statistically significant. These results suggest that CE should remain as the standard chemotherapy regimen for elderly patients with ED-SCLC.

Abstract 3934: PRMT5 is an actionable target in CDK4/6 inhibitor-resistant ER+/Rb-deficient breast cancer

RB1 loss-of-function genomic alterations confer resistance to CDK4/6 inhibitors (CDK4/6i) and are enriched post treatment of CDK4/6i in estrogen receptor-positive (ER+) metastatic breast cancer. ER+/Rb-deficient breast cancer is a rising patient population in need of novel therapeutic strategies. Herein, we used a genome-wide CRISPR screen and identified protein arginine methyltransferase 5 (PRMT5) as a molecular vulnerability in this refractory breast cancer subtype. sgRNA-induced depletion of PRMT5 arrested growth of MCF-7 and T47D RB1 knockout (RBKO) cells. PRMT5 catalyzes symmetric dimethylation of arginine (SDMA). In RBKO cells carrying doxycycline-inducible shRNA targeting the 3’UTR of PRMT5, rescue with wild-type but not an enzymatically dead mutant of PRMT5 restored cell growth, supporting that PRMT5 methyltrasferase activity is essential for growth of these cells. Gene set enrichment analysis (GSEA) of RNA-seq data revealed significant downregulation of cell cycle-related Hallmark gene signatures in RBKO cells treated with PRMT5 siRNA versus control siRNA. Both gene silencing and pharmacological blockade of PRMT5 with the small molecule inhibitor pemrametostat impeded G1-to-S cell cycle progression in MCF-7 and T47D RBKO cells and in lung, prostate, and triple-negative breast cancer cells with natural RB1 mutations or deletions, suggesting that PRMT5 inhibition can block the G1-to-S transition even in the absence of Rb. To identify the protein interactome of PRMT5 and the mechanism by which it promotes cell cycle progression in Rb-deficient cells, we performed proteomics analysis of Co-IP mass spectrometry and an SDMA post-translational modification scan and pinpointed FUS (fused in sarcoma) as a putative downstream effector of PRMT5. FUS is known to regulate RNA polymerase II (Pol II)-mediated transcription. Inhibition of PRMT5 with pemrametostat significantly reduced SDMA levels on FUS and dissociated FUS from Pol II as evidenced by FUS Co-IP and immunoblot analysis. ChIP-seq analysis revealed that treatment of RBKO cells with pemrametostat derepressed phosphorylation of Ser2 in the C-terminus of Pol II at transcription start sites (TSS) of genes involved in cell cycle progression. In accordance with the abnormal accumulation of pSer2 Pol II at TSS, pemrametostat treatment also resulted in an increased Pol II pausing index and an enrichment of intron retention splicing variants. Finally, therapeutic inhibition of PRMT5 with pemrametostat synergized with fulvestrant (a selective ER degrader) against growth of ER+/Rb-deficient breast cancer cell line- and patient-derived xenografts in mice, suggesting this combination as a novel therapeutic strategy for ER+/Rb-deficient metastatic breast cancers.

Citation Format: Chang-Ching Lin, Tsung-Cheng Chang, Yunguan Wang, Yanfeng Zhang, Andrew Lemoff, Yisheng V. Fang, He Zhang, Dan Ye, Isabel Soria-Bretones, Alberto Servetto, Kyung-min Lee, Xuemei Luo, Joseph J. Otto, Hiroaki Akamatsu, David W. Cescon, Lin Xu, Yang Xie, Joshua T. Mendell, Ariella B. Hanker, Carlos L. Arteaga. PRMT5 is an actionable target in CDK4/6 inhibitor-resistant ER+/Rb-deficient breast cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3934.

Outcomes of Chemoimmunotherapy Among Patients With Extensive-Stage Small Cell Lung Cancer According to Potential Clinical Trial Eligibility

IMPORTANCE

Chemoimmunotherapy is the standard first-line therapy for patients with extensive-stage small cell lung cancer (ES-SCLC). However, whether findings from pivotal trials can be extrapolated to the clinical practice setting remains unclear.

OBJECTIVE

To compare treatment outcome gaps following first-line chemoimmunotherapy for patients with ES-SCLC between those who met and did not meet the eligibility criteria used in previous clinical trials.

DESIGN, SETTING, AND PARTICIPANTS

A prospective cohort study was conducted from September 1, 2019, to September 30, 2020, at 32 hospitals in Japan, with at least 12 months of follow-up. Participants included consecutive patients with ES-SCLC who received carboplatin and etoposide with atezolizumab as first-line therapy.

EXPOSURES

Patients who met eligibility criteria for pivotal phase 3 clinical trials were considered trial-eligible.

MAIN OUTCOMES AND MEASURES

The primary outcome was 6-month progression-free survival. The secondary outcomes were differences in progression-free survival, overall survival, and safety according to whether key clinical trial eligibility criteria were met.

RESULTS

A total of 207 patients were analyzed (median age, 72 years; range, 46-87 years; 170 [82%] were male). Sixty-four patients (31%) were older adults (age ≥75 years), and most (184 [89%]) had an Eastern Cooperative Oncology Group performance status of 0 or 1. There were 132 (64%) trial-eligible patients. The 6-month progression-free survival rate for all patients was 38.8% (95% CI, 32.4%-45.7%). The median progression-free survival was 5.1 months in trial-eligible patients and 4.7 months in trial-ineligible patients (hazard ratio, 0.72; 95% CI, 0.53-0.97; P = .03). The proportion of patients who achieved disease control was 93% (118 of 127) in trial-eligible patients and 77% (55 of 71) in trial-ineligible patients (P = .002). The median overall survival was 15.8 months in trial-eligible patients and 13.1 months in trial-ineligible patients (hazard ratio, 0.73; 95% CI, 0.51-1.07; P = .10). The rate of severe adverse events was numerically higher among trial-ineligible patients than among trial-eligible patients (39% vs 27%; P = .07).

CONCLUSIONS AND RELEVANCE

In this cohort study, the overall treatment outcome was comparable to that reported in pivotal clinical trials. However, treatment outcomes after chemoimmunotherapy might differ between trial-eligible and trial-ineligible patients. These findings suggest that trial-eligibility criteria may be useful in clinical practice, and further studies using data from clinical practice settings are required to inform regulatory approval and clinical decision-making.

Effectiveness and safety of atezolizumab monotherapy in previously treated Japanese patients with unresectable advanced or recurrent non-small cell lung cancer: A multicenter, prospective, observational study (J-TAIL)

Introduction

The efficacy and safety of atezolizumab in previously treated patients with NSCLC have been established in the registrational phase 3 OAK trial. In this study, we evaluated the effectiveness and safety of atezolizumab monotherapy in a large real-world cohort to confirm the reproducibility of the results of the registrational trial.

Methods

This was a multicenter, prospective, single-arm observational study. Consecutive patients with previously treated NSCLC scheduled to receive atezolizumab monotherapy were enrolled. The primary end point was the 18-month overall survival (OS) rate. The incidence of adverse events (AEs) and immune-related AEs was evaluated.

Results

Overall, 1002 patients were included in the safety analysis set and 1000 in the full analysis set. Median follow-up was 11.5 months. Of the full analysis set, 62% were ineligible for the OAK trial (OAK-unlike subpopulation). The 18-month OS rate was 41.1%, with a median OS of 13.0 months (95% confidence interval: 12.2-15.1). The 18-month OS rate was 49.4% and 36.1% in OAK-like and OAK-unlike subpopulations, respectively; that in patients with Eastern Cooperative Oncology Group performance status greater than or equal to 2 was 14.3%. The incidence of AEs overall, in the OAK-like, and OAK-unlike subpopulations was 43.9%, 46.2%, and 42.5%; that of immune-related AEs was 19.0%, 20.1%, and 18.3%, respectively.

Conclusions

The findings suggest that atezolizumab may be effective and safe for previously treated patients with NSCLC in real-world settings; however, atezolizumab administration should be considered carefully regarding the benefit-risk balance for the OAK-unlike subpopulation, especially in patients with Eastern Cooperative Oncology Group performance status greater than or equal to 2.

Radiographic findings useful for diagnosis of primary chest wall lymphoma without preceding pleural disease: A case report

A 70‐year‐old man with no history of pleural diseases had a dumbbell‐shaped chest wall mass extending from the thoracic cavity to the spinal canal at the intervertebral foramen without bone destruction. Computed tomography revealed a positive a ‘pleural sandwich sign’, where the intercostal artery was enveloped by the mass. A high maximum standard uptake value was noted on fluorodeoxyglucose‐positron emission tomography. No lesions were found in areas other than the chest wall. CT‐guided biopsy was performed and he was diagnosed with primary chest wall lymphoma. This case report suggests that these radiographic findings may be helpful for diagnosing chest wall lymphomas even in patients without prior pleural disease.

Nivolumab Retreatment in Non-Small Cell Lung Cancer Patients Who Responded to Prior Immune Checkpoint Inhibitors and Had ICI-Free Intervals (WJOG9616L)

PURPOSE

To explore the efficacy of retreatment with immune checkpoint inhibitors (ICI) in patients with advanced non-small cell lung cancer (NSCLC) who responded to prior ICI and had adequate ICI-free interval.

PATIENTS AND METHODS

Patients with advanced NSCLC who had achieved complete response (CR), partial response (PR), or stable disease for ≥6 months with prior ICI therapy preceding progression were prospectively enrolled. All patients should have had ICI-free interval ≥60 days before registration. Patients were treated with nivolumab (240 mg) every 2 weeks until progression. The primary endpoint was overall response rate (ORR). Secondary endpoints included progression-free survival (PFS), overall survival, and safety (Trial Identifier, UMIN000028561).

RESULTS

Sixty-one patients were enrolled during October 2017 to February 2020, with 59 analyzed for efficacy. Regarding prior ICI, 41 patients had CR or PR. Median treatment on ICI and median ICI-free intervals were 8.1 months and 9.2 months, respectively. Twenty patients experienced immune-related adverse events (irAE) that required discontinuation of prior ICI. Nivolumab retreatment demonstrated ORR of 8.5% [95% confidence interval (CI), 2.8-18.7%] and median PFS of 2.6 months (95% CI, 1.6-2.8 months) while 5 responders had 11.1 months of median PFS. In the multivariate analysis, ICI-free interval was the only predictive factor of PFS (HR, 2.02; P = 0.02), while prior efficacy or history of irAE was not. Common adverse events were skin disorders (23%), malaise (20%), and hypoalbuminemia (15%).

CONCLUSIONS

Even in patients who initially responded to prior ICI and had ICI-free interval, once resistance occurred, retreatment with nivolumab had limited efficacy.

Abstract 516: N-glycan moiety of IgG-Fc region is a prognostic biomarker for advancednon-small cell lung cancertreated with immune checkpoint inhibitors

Background: Although it has been known that N-glycan moiety in immunoglobulin G (IgG) fragment crystallizable (Fc) region, which affects antigen dependent cellular cytotoxicity (ADCC) activity is different between healthy individuals and cancer patients, the impact of N-glycan structure on cancer treatment is unknown. Here, we evaluated the putative ADCC activity by the N-glycan moiety of IgG-Fc using serum samples and analyzed its association with clinical benefits from immune checkpoint inhibitors (ICIs) in patients with advanced non-small cell lung cancer (NSCLC).

Patients and Methods: Serum samples from healthy volunteers (HVs) were obtained from Tohoku Medical Megabank and chronic obstructive pulmonary disease (COPD) patients were enrolled as a smoking-related non-cancer disease cohort. Serum samples from advanced NSCLC patients receiving ICIs until disease progression or unacceptable toxicity were collected prior treatment. Three IgG fractions (area 1, 2 and 3) corresponding to three peaks identified by affinity chromatography using TSKgel FcR-IIIA-NPR column (Tosoh, Japan) were quantified and the putative ADCC activity was estimated based on the ratio of area 3, which associates with highest ADCC activity, to the whole area (area 3 (%)). Mann-Whitney U-test, Kaplan-Meier methods and the log-rank test were conducted for statistical analyses using JMP Pro software (ver. 14.0).

Results: Forty-two COPD and ninty-six NSCLC patients were registered in the study between Jan 2016 and May 2021 at Wakayama Medical University. Characteristics of the patients were as follows: median age, 70 (range, 49-91); male. 78%; smoker, 79%; previous treatment ≥1, 77%; performance status 0-1, 82%; stage IV, 69%; squamous/non-squamous/unknown, 29/69/2%; nivolumab/pembrolizumab/atezolizumab, 46/42/12%. The objective response rate was 25.0% (24/96). The median progression free survival (PFS) and median overall survival (OS) was 72 days (95%CI, 49 to 127) and 310 days (95% CI, 216 to 453), respectively. The area 3 (%) was significantly lower in NSCLC patients than both HVs and COPD patients (P=0.0002 and p&lt;0.0001, respectively) and no significant difference was observed between HVs and COPD samples. When time-to-event analysis was conducted by dividing into two groups in NSCLC patients at the median of the area 3 (%), OS was significantly longer in patient with higher ratio than those with lower one in both entire cohort (median OS, 952 vs 482; 95% CI, 453 days-not reached (NR) and 233-744 days; p=0.0236) and 2nd line subset (median OS, 952 vs 292; 95% CI, 453 days-NR and 120-692 days; p=0.001). Evaluation of IgG fraction was not associated with tumor response or PFS in this study cohort.

Conclusion: Our results suggest that evaluation of the N-glycan moiety of IgG-Fc in peripheral blood has a potential as a prognostic biomarker in advanced NSCLC patients treated with ICIs.

Citation Format: Jun Oyanagi, Yasuhiro Koh, Yasuyuki Akiyama, Atsushi Morimoto, Koichi Sato, Shunsuke Teraoka, Daichi Fujimoto, Nahomi Tokudome, Atsushi Hayata, Yuichi Ozawa, Hiroaki Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. N-glycan moiety of IgG-Fc region is a prognostic biomarker for advancednon-small cell lung cancertreated with immune checkpoint inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 516.

Impact of underrepresented populations on clinical outcomes of chemo-immunotherapy for extensive-stage small cell lung cancer: Real-world prospective cohort study

8567

Background: Chemo-immunotherapy is the standard 1st-line therapy for patients with extensive-stage small cell lung cancer (ES-SCLC). Prospective data about underrepresented populations outside the clinical trial such as elderly or poor risk has not been revealed. Methods: We conducted a 32-hospitals prospective cohort study of consecutive patients with ES-SCLC who received carboplatin and etoposide with atezolizumab as 1st-line therapy between September 2019 and September 2020. The primary outcome was 6-months progression-free survival (PFS) probability of all patients. The secondary outcomes were overall survival (OS), PFS, time to treatment failure, objective response rate, safety, and differences in efficacy and safety depending on whether or not the key eligible study criteria of previous trials are met. Results: In total, 207 patients with ES-SCLC were analyzed. The median age was 72 years, and 64 patients (31%) were elderly (≥75 years). Most patients (89%) had a performance status (PS) of 0 or 1. As a result, 132 (64%) was categorized as eligible patients. The 6-months PFS probability of all patients was 38.8 % (95%CI:32.4-45.7%). Between eligible and ineligible patients, there was significant difference of patients who attained disease control (93% versus 77%, p = 0.002). Median PFS was significantly longer in eligible patients than ineligible patients (5.1 vs. 4.7 months; P =.03, HR 0.72 (95% CI 0.53–0.97)), and median OS was longer in eligible patients than ineligible patients, without any significant difference (15.8 vs. 13.1 months; P =.10, HR 0.73 (95% CI 0.51–1.07)). Survival analysis identified a PS score of 0-1 (HR: 0.60, 95% CI: 0.39-0.97, p = 0.03) as a significant predictor of better PFS, while PS score of 0-1 (HR: 0.51, 95% CI: 0.31-0.89, p = 0.01) and younger patients ( < 75 years) (HR: 0.66, 95% CI: 0.45-0.97, p = 0.03) as significant-good predictor of OS. The rate of severe AEs was higher in ineligible patients than in eligible (39% vs. 27%, respectively; p = 0.07), although the difference was not significant. Older age was significantly associated with severe AEs (p = 0.049). Conclusions: The real-world efficacy of chemo-immunotherapy for ES-SCLC was similar to that of pivotal clinical trials. However, trial-ineligible patients with ES-SCLC had poor treatment outcome and the higher rates of severe adverse events in this prospective cohort study. Our study suggests that positive results among the trial eligible patients may not translate to ineligible patients. Clinical trial information: UMIN000038064.

Phase 2 study of tarlatamab, a DLL3-targeting, half life–extended, bispecific T-cell engager (HLE BiTE)immuno-oncology therapy, in relapsed/refractory small cell lung cancer (SCLC)

TPS8603

Background: SCLC is characterized by rapid growth and early development of metastases. Platinum-based first-line chemotherapy is associated with a high initial response rate; however, disease recurrence is common. Delta-like ligand 3 (DLL3) is a Notch ligand that is upregulated and aberrantly expressed on the cell surface in most SCLC, making it a compelling therapeutic target. Tarlatamab is an HLE BiTE immuno-oncology therapy designed to bind DLL3 on target cancer cells and CD3 on T cells, forming a cytolytic synapse inducing T cell activation and expansion and T cell-dependent killing of tumor cells. Interim results of an ongoing first-in-human study in patients with relapsed/refractory SCLC (NCT03319940) show preliminary evidence for tarlatamab efficacy in pretreated patients with confirmed partial responses in 20% of patients and duration of response of 8.7 months (Owonikoko TK, et al. Abstract 8510. Presented at: ASCO Annual Meeting, June 4–8, 2021; Virtual). Grade ≥ 3 treatment-related AEs (TRAEs) occurred in 27% of patients and TRAEs resulted in discontinuation in 5% of patients. This promising efficacy/safety profile supports further study of tarlatamab in SCLC. Methods: NCT05060016 is a phase 2, open-label study evaluating tarlatamab in patients with relapsed/refractory SCLC after two or more lines of prior treatment. Part 1 is a dose characterization phase in which subjects will be randomized 1:1 to two active doses of tarlatamab. Part 2 will continue enrollment for the selected target dose only based on interim analysis of Part 1. Key eligibility criteria include adults with histologically or cytologically confirmed SCLC whose disease progressed/recurred after two or more lines of prior treatment including at least 1 platinum-based regimen (including a PD-L1 inhibitor, if standard of care, with certain exceptions per protocol), treated brain metastases, ECOG performance status ≤1, and life expectancy ≥ 12 weeks in the opinion of the investigator. The primary endpoint for the primary analysis is ORR per RECIST 1.1 as assessed by blinded independent central review. Secondary objectives are to evaluate antitumor activity by additional measures (duration of response, progression-free survival, disease control rate and duration, overall survival), safety and tolerability, immunogenicity, and pharmacokinetics. Sites in North America, Asia and Europe are participating in the trial with subjects already enrolled and enrollment ongoing. Clinical trial information: NCT05060016.

Impact of pre-existing interstitial lung abnormal shadow on lung injury development and severity in patients of non-small cell lung cancer treated with osimertinib

Background

First‐generation epidermal growth factor receptor‐tyrosine kinase inhibitor (EGFR‐TKI) sometimes causes lung injury, thereby affecting survival. Although pre‐existing interstitial lung abnormal shadow (pre‐ILS) increases the risk of lung injury by EGFR‐TKIs, its impact on osimertinib, a third‐generation EGFR‐TKI, remains unknown.

Patients and Methods

This retrospective cohort study consecutively enrolled patients of EGFR‐mutated non‐small cell lung cancer treated with osimertinib. Computed tomography images were obtained and evaluated independently by three pulmonologists in a blinded manner. Factors associated with lung injury were assessed using a logistic regression model. Survival curves were calculated by the Kaplan–Meier method and compared using a log‐rank test.

Results

Of the 195 patients, 40 had pre‐ILS, and 21 (8 with and 13 without pre‐ILS) developed lung injury during the observation period. Multivariate analysis revealed that pre‐ILS was independently associated with lung injury (odds ratio, 3.1; 95% confidence interval [CI], 1.1–8.2; p = 0.025). Severe (≥Grade 3) lung injury was observed in eight (4.1%) patients, of whom, two (5%) and six (3.9%) had and did not have pre‐ILS (p = 0.67), respectively. Grade 5 lung injury was not observed, and survival curves were similar between the patients who developed lung injury and those who did not (median 11 vs. 12 months; hazard ratio, 1.2; 95% CI, 0.56–2.7; p = 0.60).

Conclusions

Pre‐ILS increased the risk of lung injury in patients of non‐small cell lung cancer treated with osimertinib, while the severity of lung injury was not clearly affected by the presence of pre‐ILS.

Abstract P5-17-09: A genome-wide CRISPR screen identifies PRMT5 as a novel therapeutic target in ER+/RB1-deficient breast cancer

Background: CDK4/6 inhibitors (CDK4/6i) have improved survival of patients with advanced estrogen receptor-positive (ER+) breast cancer. However, this benefit is transient as virtually all these tumors eventually develop drug resistance and recur. Clinical studies have reported an association of RB1 loss-of-function genomic alterations with acquired resistance to CDK4/6i. Given the enrichment of RB1 alterations post CDK4/6i treatment, ER+/RB1-deficient breast cancer will become a rising patient population in need of discovery of novel treatment strategies. In this study, we sought to identify actionable vulnerabilities for this refractory breast cancer subtype using a genome-wide CRISPR screen. Methods: RB1 was knocked out in ER+ MCF-7 and T47D breast cancer cells using CRISPR-Cas9; complete gene knockout was confirmed by PCR-based genotyping, Sanger sequencing, and immunoblot analysis. Isogenic RB1 knockout (RBKO) and wild-type (WT) T47D cells were used for the genome-wide CRISPR screen. MAGeCKFlute was used to identify differentially essential genes in T47D RBKO vs WT cells; Gene Ontology (GO) analysis was used to prioritize hits. MCF-7 and T47D RBKO cells were used for validating and studying the function of the identified genes. Results: Knockout of RB1 in MCF-7 and T47D cells increased IC50 of abemaciclib, palbociclib, and ribociclib 10-200 fold compared to WT cells. RNA-seq analysis showed upregulation of E2F target gene expression in RBKO vs WT cells. The CRISPR screen revealed that CCND1 and CDK4 lost their essentiality in T47D RBKO cells, suggesting that loss of RB1 uncouples the CDK4/Cyclin D1 complex from E2F-regulated transcription. GO analysis of the top 50 differentially essential hits of RBKO vs WT cells showed an enrichment of protein arginine methyltransferase activity, primarily PRMT5, which post-translationally mono-methylates and symmetrically di-methylates protein arginine. In agreement with this finding, PRMT5 knockout by three individual sgRNAs resulted in more potent growth inhibition of MCF-7 and T47D RBKO cells than WT cells. Further, transfection of PRMT5 siRNA or treatment with the PRMT5 small molecule inhibitor GSK3326595 - currently in clinical trials - resulted in G1 arrest of MCF-7 and T47D RBKO cells as assayed by propidium iodide staining but did not induce caspase 3/7 or PARP cleavage (apoptosis). RNA-seq of PRMT5 siRNA vs control siRNA in MCF-7 and T47D RBKO cells exhibited significant downregulation of E2F Hallmark gene signature, further suggesting PRMT5 inhibition as a strategy to suppress E2F-regulated gene expression when cells lose Rb. The CRISPR screen also revealed that transcription factors that drive ER signaling, such as FOXA1, GATA3, MYC, SPDEF, and ESR1 (the gene encoding ERα), were commonly essential in both T47D WT and RBKO cells. Estrogen deprivation or treatment with fulvestrant inhibited estrogen responsive element (ERE) luciferase reporter activity, expression of putative E2F target genes, and proliferation of both WT and RBKO cells, suggesting that ER+ cells still rely on ERα irrespective of RB1 status. Treatment of MCF-7 and T47D RBKO cells with fulvestrant and GSK3326595 resulted in more potent growth inhibition than each drug alone, suggesting a novel approach to treat ER+/RB1-deficient breast cancer. We are currently testing the antitumor activity of fulvestrant plus GSK3326595 against RBKO xenografts as well as the requirement of arginine methyltransferase activity associated with PRMT5 for growth of ER+/RB1-deficient breast cancer cells. Conclusion: PRMT5 is essential for proliferation of ER+/RB1-deficient breast cancer cells. Targeting PRMT5 in combination with anti-estrogens is a novel and testable strategy to suppress E2F-regulated cell cycle progression of this CDK4/6 inhibitor-resistant breast cancer subtype.

Citation Format: Chang-Ching Lin, Tsung-Cheng Chang, Alberto Servetto, Kyung-min Lee, He Zhang, Yunguan Wang, Dan Ye, Sumanta Chatterjee, Dhivya R Sudhan, Hiroaki Akamatsu, Yang Xie, Joshua T Mendell, Ariella B Hanker, Carlos L Arteaga. A genome-wide CRISPR screen identifies PRMT5 as a novel therapeutic target in ER+/RB1-deficient breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-17-09.

Pre-treatment serum protein levels predict survival of non-small cell lung cancer patients without durable clinical benefit by PD-1/L1 inhibitors

While PD-1/L1 inhibitors are characterized by durable tumor control, they also prolong survival without prolongation of progression-free survival (PFS) in part of patients. However, little is known about the factors and mechanisms involved in this. Between December 2015 and September 2018, 106 patients with advanced non-small cell lung cancer treated with ICI monotherapy were enrolled in a prospective-observational study. Sixty-nine of whom progressed or died within 6 months after ICI initiation were defined as patients without durable clinical benefit (NDBs). Clinical factors and 39 serum proteins before ICI initiation and at the time of progressive disease (PD) were explored for an association with overall survival (OS) and OS after PD (OS-PD). As a result, median PFS, OS, and OS-PD were 44 days [95% confidence interval (CI): 39-56), 211 days (95% CI: 158-425), and 193 days (95% CI: 118-349), respectively. By multivariate analysis for OS, CRP (> 1.44 mg/dl) [HR 2.59 (95% CI:1.33-5.04), P = 0.005] and follistatin (> 685 pg/ml) [HR 2.29 (95% CI:1.12-4.69), P = 0.023] before ICI initiation were significantly predictive. Notably, no serum protein at the time of PD was predictive for OS-PD. There were also no serum predictive factors of OS in the 33 patients with durable clinical benefit. In conclusion, serum levels of CRP and follistatin before ICI initiation, not at the time of PD, are predictive for OS in NDBs, suggesting long-term survivor in NDBs are predetermined by the immune status before ICI initiation.

Abstract P014: Clinical impact of evaluating serum IgG fractions in advanced non-small cell lung cancer treated with immune checkpoint inhibitors

Background: Structure of N-linked glycan in immunoglobulin G (IgG) fragment crystallizable (Fc) region is associated with antigen-dependent cellular cytotoxicity (ADCC) activity. Although it has been known that N-glycan moiety is different between healthy individuals and cancer patients, the relationship between the N-glycan structure and treatment response in cancer patients is unknown. Here, we evaluated the putative ADCC activity by the N-glycan moiety of IgG-Fc using peripheral blood and analyzed its association with clinical benefits from immune checkpoint inhibitors (ICIs) in patients with advanced non-small cell lung cancer (NSCLC). Patients and Methods: Advanced NSCLC patients received nivolumab, pembrolizumab or atezolizumab treatment until disease progression or unacceptable toxicity. Serum samples were collected at baseline. Tumor responses were classified into complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD) based on RECIST v1.1. Durable clinical benefit (DCB) was defined as patients whose response was lasting over 6 months. Three IgG fractions (area 1, 2 and 3) corresponding to three peaks identified by affinity chromatography using TSKgel FcR-IIIA-NPR column (Tosoh, Japan) were quantified and the putative ADCC activity was estimated based on the ratio of area 3, which associates with highest ADCC activity, to the whole area. All statistical analyses were carried out using JMP Pro software (ver. 14.0). Mann-Whitney U-test was conducted. Time to event analysis was conducted using Kaplan-Meier methods and the log-rank test. Results: Ninety-seven patients were registered in the study between Jan 2016 and Nov 2018 at Wakayama Medical University. Characteristics of the patients were as follows: median age, 70 (range, 49-91); male. 78%; smoker, 79%; previous treatment ≥1, 77%; performance status 0-1, 82%; stage III/IV, 31/69%; squamous/non-squamous/unknown, 29/69/2%; nivolumab/pembrolizumab/atezolizumab, 46/42/12%. The objective response rate was 25.0% (24/96) and the disease control rate was 55.2% (53/96). The DCB rate was 45.4% (44/96). The median progression free survival (PFS) was 72 days (95%CI, 49 to 127) and median overall survival (OS) was 310 days (95% CI, 229 to 475). When time-to-event analysis was conducted by dividing into two groups at the median of the ratio of area 3 to the whole area, OS was significantly longer in patient with higher ratio than those with lower one in both entire cohort (median OS, 952 vs 482; 95% CI, 482 days-not reached and 233-744 days; log rank p=0.0292) and 2nd line cohort (median OS, 952 vs 292; 95% CI, 453 days-not reached and 120-692 days; log rank p=0.0010). Evaluation of IgG fraction was not associated with tumor response or PFS in this study cohort. Conclusion: Our results suggest that evaluation of the N-glycan moiety of IgG-Fc in peripheral blood has a potential as a prognostic biomarker in advanced NSCLC patients treated with ICIs.

Citation Format: Jun Oyanagi, Yasuhiro Koh, Yasuyuki Akiyama, Atsushi Morimoto, Koichi Sato, Shunsuke Teraoka, Daichi Fujimoto, Nahomi Tokudome, Atsushi Hayata, Yuichi Ozawa, Hiroaki Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Clinical impact of evaluating serum IgG fractions in advanced non-small cell lung cancer treated with immune checkpoint inhibitors [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P014.

Predictive value of EGFR mutation in non-small-cell lung cancer patients treated with platinum doublet postoperative chemotherapy

The mutation status of tumor tissue DNA (n = 389) of resected stage II‐III non‐squamous non–small‐cell lung cancer (Ns‐NSCLC) was analyzed using targeted deep sequencing as an exploratory biomarker study (JIPANG‐TR) for the JIPANG study, a randomized phase III study of pemetrexed/cisplatin (Pem/Cis) vs vinorelbine/cisplatin (Vnr/Cis). The TP53 mutation, common EGFR mutations (exon 19 deletion and L858R), and KRAS mutations were frequently detected. The frequency of the EGFR mutation was significant among female patients. Patients with an EGFR mutation‐positive status had a significantly shorter recurrence‐free survival (RFS) time (24 mo vs not reached) (HR, 1.64; 95% CI, 1.22‐2.21; P = .0011 for EGFR mutation status). Multivariable analysis identified both the pathological stage and EGFR mutation status as independent prognostic factors for RFS (HR, 1.78; 95% CI, 1.30‐2.44; P = .0003 for disease stage; and HR, 1.57; 95% CI, 1.15‐2.16; P = .0050 for EGFR mutation status). This study demonstrated that the EGFR mutation has either a poor prognostic or predictive impact on a poor response to postoperative chemotherapy with platinum doublet chemotherapy for stage II‐III Ns‐NSCLC patients. This result supports a role for mandatory molecular diagnosis of early‐stage Ns‐NSCLC for precision oncology and signifies the importance of adjuvant for the 3rd generation tyrosine kinase inhibitor rather than platinum‐based chemotherapy. This study is registered with the UMIN Clinical Trial Registry (UMIN 000012237).

Pembrolizumab Plus Amrubicin in Patients With Relapsed SCLC: Multi-Institutional, Single-Arm Phase 2 Study

Introduction

In patients with relapsed SCLC, amrubicin (AMR) is the current standard treatment in Japan. Nevertheless, its efficacy is not satisfactory and prognosis is poor. Preclinical study suggested that anthracycline agent might induce immunogenic cell death and work synergistically with immune checkpoint inhibitors.

Methods

Patients with relapsed SCLC who relapsed after completion of platinum-containing regimen were registered. Patients were treated with pembrolizumab (200 mg, flat dose on d 1, every 3 wk for 2 y) plus AMR (40 mg/m² on d 1-3, every 3 wk until progression). Primary end point was overall response rate (ORR). Secondary end points consisted of progression-free survival (PFS), overall survival, and safety. On the basis of the hypothesis that this treatment will improve ORR from 20% to 40% (0.1 of one-sided α and power of 0.8), 25 patients are required (trial identifier: NCT03253068).

Results

Between November 2017 and October 2019, a total of 25 patients were enrolled. Most participants (88%) relapsed within 90 days after platinum-containing therapy and all patients were immune checkpoint inhibitor-naive. ORR, the primary end point, was 52.0% (95% confidence interval [CI]: 31.3%-72.2%). Median PFS was 4.0 months (95% CI: 2.8-7.0 mo), and PFS rate at 1 year was 14.4%. Median overall survival was 10.6 months (95% CI: 7.3-21.3 mo). Common adverse events greater than or equal to grade 3 were neutropenia (64%), leukopenia (40%), and febrile neutropenia (16%). No treatment-related deaths occurred.

Conclusions

Among patients with relapsed SCLC, pembrolizumab plus AMR was effective and tolerable.

Co-occurring gain-of-function mutations in HER2 and HER3 modulate HER2/HER3 activation, oncogenesis, and HER2 inhibitor sensitivity

Activating mutations in HER2 (ERBB2) drive the growth of a subset of breast and other cancers and tend to co-occur with HER3 (ERBB3) missense mutations. The HER2 tyrosine kinase inhibitor neratinib has shown clinical activity against HER2-mutant tumors. To characterize the role of HER3 mutations in HER2-mutant tumors, we integrate computational structural modeling with biochemical and cell biological analyses. Computational modeling predicts that the frequent HER3E928G kinase domain mutation enhances the affinity of HER2/HER3 and reduces binding of HER2 to its inhibitor neratinib. Co-expression of mutant HER2/HER3 enhances HER2/HER3 co-immunoprecipitation and ligand-independent activation of HER2/HER3 and PI3K/AKT, resulting in enhanced growth, invasiveness, and resistance to HER2-targeted therapies, which can be reversed by combined treatment with PI3Kα inhibitors. Our results provide a mechanistic rationale for the evolutionary selection of co-occurring HER2/HER3 mutations and the recent clinical observations that HER3 mutations are associated with a poor response to neratinib in HER2-mutant cancers.

Nuclear FGFR1 Regulates Gene Transcription and Promotes Antiestrogen Resistance in ER+ Breast Cancer

PURPOSE

FGFR1 overexpression has been associated with endocrine resistance in ER⁺ breast cancer. We found FGFR1 localized in the nucleus of breast cancer cells in primary tumors resistant to estrogen suppression. We investigated a role of nuclear FGFR1 on gene transcription and antiestrogen resistance.

EXPERIMENTAL DESIGN

Tumors from patients treated with letrozole were subjected to Ki67 and FGFR1 IHC. MCF7 cells were transduced with FGFR1(SP-)(NLS) to promote nuclear FGFR1 overexpression. FGFR1 genomic activity in ER⁺/FGFR1-amplified breast cancer cells ± FOXA1 siRNA or ± the FGFR tyrosine kinase inhibitor (TKI) erdafitinib was examined by chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing (RNA-seq). The nuclear and chromatin-bound FGFR1 interactome was investigated by mass spectrometry (MS).

RESULTS

High nuclear FGFR1 expression in ER⁺ primary tumors positively correlated with post-letrozole Ki67 values. Nuclear FGFR1 overexpression influenced gene transcription and promoted resistance to estrogen suppression and to fulvestrant in vivo. A gene expression signature induced by nuclear FGFR1 correlated with shorter survival in the METABRIC cohort of patients treated with antiestrogens. ChIP-Seq revealed FGFR1 occupancy at transcription start sites, overlapping with active transcription histone marks. MS analysis of the nuclear FGFR1 interactome identified phosphorylated RNA-Polymerase II and FOXA1, with FOXA1 RNAi impairing FGFR1 recruitment to chromatin. Treatment with erdafitinib did not impair nuclear FGFR1 translocation and genomic activity.

CONCLUSIONS

These data suggest nuclear FGFR1 contributes to endocrine resistance by modulating gene transcription in ER⁺ breast cancer. Nuclear FGFR1 activity was unaffected by FGFR TKIs, thus supporting the development of treatment strategies to inhibit nuclear FGFR1 in ER+/FGFR1 overexpressing breast cancer.

Abstract 2976: Establishment of organoids derived from patients with advanced thoracic malignancies

Background: In the past decade, three-dimensional organoid culture derived from various tumors has been applied to cancer research. Compared to the conventional two-dimensional cell culture, organoid culture recapitulates in vivo system and furthermore, its high establishment rate may hold the potential to help decision-making for precision medicine. However, it remains challenging to establish organoids from advanced thoracic malignancies due to a limited amount of biopsy specimens. Here, we report the attempt to establish organoids from endoscopic biopsy specimens and pleural effusions in patients with advanced thoracic malignancies

Methods: Organoid culture was attempted using biopsy specimens or pleural effusions from patients who underwent transbronchial biopsy, thoracoscopic biopsy or thoracentesis. After confirming the presence of malignant cells by rapid on-site evaluation, biopsy specimens were digested with collagenase and dispase at 37°C followed by being harvested and cultured in Matrigel. As for pleural effusions, mononuclear cells were isolated by ficoll density gradient centrifugation and CD45+ cells were depleted using anti-CD45 magnetic beads. Then, the resultant cells were cultured in Matrigel. Next-generation sequencing was performed to confirm cancer-related somatic mutations using Ion PGM system. Cell viability assay was performed by resazurin assay.

Results:142 patients were registered in the study between May 2019 and October 2020 at Wakayama Medical University. Fifty-one cases were excluded because of negative diagnosis for malignancy, retraction of the consent or risk of bleeding associated with biopsy. We attempted to culture organoids using 98 samples from 91 patients. The types of malignancies were as follows: non-small cell lung cancers (NSCLC)/SCLC/others, 80/8/3. A total of 33 organoids were successfully cultured with sustainable proliferation and 16 were successfully cryopreserved. Established organoids were confirmed to harbor the same mutations as detected by clinical testing with tissue samples and to form tumors in a xenotransplantation model. HLCO-75, established from pleural effusion at disease progression after osimertinib treatment was genotyped and found to gain ERBB2 V777L mutation in exon 20 in addition to original EGFR L858R mutation. Marked growth-inhibitory effect by poziotinib, a HER2 tyrosine kinase inhibitor with IC50 value 6 nM was observed whereas not by TAS6417, another EGFR/HER2 exon 20 inhibitor, suggesting the potential of organoid culture for decision-making in cancer precision medicine.

Conclusion: Our results suggest that organoid culture is feasible from small biopsy specimens and these organoids could be applied for personalized medicine.

Citation Format: Jun Oyanagi, Yasuhiro Koh, Koichi Sato, Masanori Tanaka, Katsuyuki Furuta, Takeya Sugimoto, Ryota Shibaki, Shunsuke Teraoka, Daichi Fujimoto, Nahomi Tokudome, Hiroaki Akamatsu, Atsushi Hayata, Atsushi Hayata, Yuichi Ozawa, Hiroki Ueda, Nobuyuki Yamamoto. Establishment of organoids derived from patients with advanced thoracic malignancies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2976.

Nivolumab with carboplatin, paclitaxel, and bevacizumab for first-line treatment of advanced nonsquamous non-small-cell lung cancer

BACKGROUND

This international, randomized, double-blind phase III study (ONO-4538-52/TASUKI-52) evaluated nivolumab with bevacizumab and cytotoxic chemotherapy as first-line treatment for nonsquamous non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Between June 2017 and July 2019, this study enrolled treatment-naïve patients with stage IIIB/IV or recurrent nonsquamous NSCLC without sensitizing EGFR, ALK, or ROS1 alterations. They were randomly assigned in a 1 : 1 ratio to receive nivolumab or placebo in combination with carboplatin, paclitaxel, and bevacizumab every 3 weeks for up to six cycles, followed by nivolumab/placebo with bevacizumab until progressive disease or unacceptable toxicity. The primary endpoint was progression-free survival (PFS) assessed by an independent radiology review committee (IRRC).

RESULTS

Overall, 550 patients from Japan, Korea, and Taiwan were randomized; of these patients, 273 and 275 received the nivolumab and placebo combinations, respectively. In the present preplanned interim analysis with a median follow up of 13.7 months, the IRRC-assessed median PFS was significantly longer in the nivolumab arm than in the placebo arm (12.1 versus 8.1 months; hazard ratio 0.56; 96.4% confidence interval 0.43-0.71; P < 0.0001). The PFS benefit was observed across all patients with any programmed death-ligand 1 (PD-L1) expression levels including PD-L1-negative patients. The IRRC-assessed objective response rates were 61.5% and 50.5% in the nivolumab and placebo arms, respectively. The incidence of treatment-related adverse events of grade 3 or 4 was comparable between the two arms; treatment-related adverse events leading to death were observed in five and four patients in the nivolumab and placebo arms, respectively.

CONCLUSION

The TASUKI-52 regimen should be considered a viable new treatment strategy for treatment-naïve patients with advanced nonsquamous NSCLC.

A randomized phase II/III study comparing carboplatin and irinotecan with carboplatin and etoposide for the treatment of elderly patients with extensive-disease small cell lung cancer (JCOG1201/TORG1528)

8571

Background: Carboplatin and etoposide is the current standard treatment for elderly extensive-disease small-cell lung cancer (ED-SCLC). The purpose of this study is to evaluate the efficacy and safety of carboplatin and irinotecan compared with carboplatin and etoposide in elderly Japanese patients with ED-SCLC in a randomized phase II/III design. Methods: Eligibility included histologically or cytologically proven SCLC, no previous systemic chemotherapy, performance status of 0 to 2, and aged 71 years or older. Patients received carboplatin (AUC 5 mg/ml/min on day 1) and etoposide (80 mg/m2 on day 1 to 3) (CE) every 3 weeks for 4 cycles or carboplatin (AUC 4 mg/ml/min on day 1) and irinotecan (50 mg/m2 on day 1 and 8) (CI) every 3 weeks for 4 cycles. In the phase II part, the primary endpoint was the objective response rate of the CI arm and the secondary endpoint was adverse events. In the phase III part, the primary endpoint was overall survival, and the secondary endpoints were progression-free survival, objective response rate, adverse events, and symptom score. This study was designed to confirm the superiority of CI arm in terms of overall survival over CE arm. The median survival time with CI arm was expected to be increased by 3.5 months with hazard ratio (HR) of 0.750 (10.5 vs. 14.0 months). The sample size was set at 250 to observe the required number of events of 227 with one-sided alpha level of 0.05, a power of 70%, an accrual period of 6.5 years, and a follow-up period of 1.5 years. Results: Between December 2013 and June 2019, 258 patients were randomized (CE arm, 129 patients; CI arm, 129 patients). The median age was 75 (range, 71-90). The characteristics of the patients were well balanced between CE arm and CI arm. Overall survival, progression-free survival, and objective response rate of CE arm vs. CI arm were 12.0 (95% CI, 9.3-13.7) vs. 13.2 (95% CI, 11.1-14.6) months (HR, 0.848 (95% CI, 0.650-1.105)) (one-sided P=0.11), 4.4 (95% CI, 4.0-4.7) vs. 4.9 months (95% CI, 4.5-5.2) (HR, 0.851 (95% CI, 0.664-1.090)) (two-sided P=0.21), and 59.7% (77 of 129) vs. 64.3% (83 of 129), respectively. Symptom score showed no significant difference between the arms. Higher incidences of myelosuppression of grade 3 or worse occurred with CE arm, whereas higher incidences of gastrointestinal toxicity of grade 3 or worse occurred with CI arm. Three treatment-related deaths including lung infection in CE arm and lung infection and sepsis in CI arm were observed. Conclusions: Efficacy tended to be favorable in carboplatin and irinotecan arm, but there was no statistically significant difference. These results indicate that carboplatin and etoposide is a still standard treatment in elderly Japanese patients with ED-SCLC. Clinical trial information: 000012605.

Tumor expression of cGAS, not STING, negatively impacts on the efficacy of PD-1/L1 inhibitors in non-small cell lung cancer with PD-L1 TPS ≥50

e21048

Background: The cGAS/STING pathway is an innate immune pathway that promotes cytokine production in response to cytoplasmic DNA, and its activation is important for the induction of anti-tumor immunity. However, predictivity of cGAS/STING tumor expression on the efficacy of PD-1/L1 inhibitors and subsequent immune responses (e.g., changes in serum cytokines) remain to be elucidated. Non-small cell lung cancer with PD-L1 tumor proportion score (TPS) of 50% or higher respond well to immune checkpoint inhibitor (ICI) monotherapy, but there is still a poor response group among them, and the extraction of such patients is an urgent issue. Methods: This is a post hoc analysis of prospective biomarker study, which enrolled 106 patients with advanced non-small cell lung cancer (NSCLC) who were treated with ICI monotherapy between December 2015 and September 2018. We investigated in 68 patients with preserved evaluable tissue samples taken before start of ICI treatment. cGAS, STING, and PD-L1 expression in tumors were stained by immunohistochemistry. cGAS and STING were evaluated by H-score. Using peripheral blood which was collected by the observational study, 41 serum proteins at the time of PD-1/L1 inhibitors initiation and in 4 – 6 weeks later were quantified. Results: The median cGAS and STING H-SCORE were 220 (5 – 300) and 190 (0 – 300), respectively. There were no differences in cGAS or STING H-SCORE between PD-L1 high (TPS ≥50) and low (TPS < 50) groups ( p= 0.990 and 0.283). Cases were divided into two groups according to median of the H-SCORE, respectively, and compared. Unexpectedly, cGAS high (H-SCORE ≥220) patients showed significantly shorter progression free survival of ICI when PD-L1 TPS ≥50 (median progression free survival (PFS); 143 days vs. not reached, p = 0.028) and progression free rate at 18 months was 7 and 53%, while no association was observed when PD-L1 TPS < 50 (median PFS; 47 vs. 61 days, p= 0.798). STING tumor expression was not associated with PFS regardless of PD-L1 TPS. In cytokine analysis, cGAS high was associated with significantly higher serum concentrations of TGF-β1 and β2 before ICI initiation (47.5 vs. 22.3hg/l, p= 0.023; 2118 vs. 882rg/ml, p= 0.037), and H-SCORE of cGAS, not STING, were significantly correlated with TGF-β1 and β2 basal levels (r = 0.447, p= 0.009; r = 0.373, p= 0.033). Analysis about fold change from baseline to 4 – 6 weeks later of 41 cytokines revealed that leptin significantly increased in cGAS high tumor while no difference was seen in all of cytokines between STING high and low tumor. Conclusions: Tumor expression (H-Score) of cGAS, not STING, is a candidate for predictor of poor response to ICI monotherapy in NSCLC with PD-L1 high (TPS ≥50). cGAS tumor expression may be associated with TGF-β producing, immune-suppressive tumor microenvironment in NSCLC. Clinical trial information: UMIN000024414.

Comparison of Systemic Inflammatory Response Syndrome and quick Sequential Organ Failure Assessment scores in predicting bacteremia in the emergency department

Aim

The emergency department requires simple and useful clinical indicators to identify bacteremia. This retrospective study explored the Systemic Inflammatory Response Syndrome (SIRS) and quick Sequential Organ Failure Assessment (qSOFA) scores for predicting bacteremia.

Methods

Between April and September 2017, we assessed blood cultures of 307 patients in our emergency department. We calculated the SIRS and qSOFA scores for these patients and evaluated their correlation with bacteremia.

Results

Of 307 patients, 66 (21.5%) had bacteremia, 237 (77.2%) were SIRS-positive, and 123 (40.0%) were qSOFA-positive. The sensitivity and specificity of the SIRS score for predicting bacteremia were 87.9% and 25.7%, respectively. The sensitivity and specificity of the qSOFA score were 47.0% and 61.8%, respectively. Multivariate analysis revealed that body temperature (odds ratio, 2.16; 95% confidence interval, 1.22-3.84; P = 0.009) and blood pressure (odds ratio, 2.72; 95% confidence interval, 1.39-5.35; P = 0.004) significantly associated with bacteremia.

Conclusions

The SIRS score was a more sensitive indicator than the qSOFA score for predicting bacteremia.

Bloodborne Cytokines for Predicting Clinical Benefits and Immune-Related Adverse Events in Advanced Non-Small Cell Lung Cancer Treated With Anti-Programmed Cell Death 1 Inhibitors

BACKGROUND

Programmed cell death ligand 1 is a biomarker of immune checkpoint inhibitors (ICIs) for treating advanced non-small-cell lung cancer (NSCLC). Here, we evaluated serum proteins from patients with advanced NSCLC treated with ICIs to determine their potential as noninvasive predictive biomarkers for efficacy and immune-related adverse events (irAEs).

PATIENTS AND METHODS

Patients with advanced NSCLC who received nivolumab or pembrolizumab monotherapy until disease progression or unacceptable toxicity were integrated with previously reported nivolumab-treated patients. Blood samples were collected serially from baseline until the disease progressed. Serum protein levels were quantified using the Luminex assay. Associations of clinical benefit (CB) and onset of irAEs with serum protein levels were evaluated.

RESULTS

Sixty-three patients with advanced NSCLC were studied, and we used 63 and 47 paired serum samples at baseline and the second sampling point, respectively, for efficacy analysis. Baseline growth-regulated oncogene 1 (GRO-1) levels were significantly lower in durable CB (DCB) patients than in non-DCB patients (P < .05). Changes in monocyte chemoattractant protein 1 (MCP-1) levels significantly decreased between baseline and the second sampling point (P < .05). Patients with the low GRO-1/decreased MCP-1 subtype showed significantly longer progression-free survival (PFS) and overall survival (OS) than the high GRO-1/increased MCP-1 subgroup did (median PFS, not reached vs. 47 days, P < .0001; median OS, 985 days vs. 148 days, P = .0002, respectively). Elevated GRO-1 levels were associated with immune-related adverse event onset.

CONCLUSIONS

Serum GRO-1 and MCP-1 levels can identify patients with advanced NSCLC who are likely to benefit from ICI treatment. Time-course tracing of these protein levels might be valuable in ICI treatment.

Frequency shift algorithm: Application to a frequency-domain multiplexing readout of x-ray transition-edge sensor microcalorimeters

In the frequency-domain multiplexing (FDM) scheme, transition-edge sensors (TESs) are individually coupled to superconducting LC filters and AC biased at MHz frequencies through a common readout line. To make efficient use of the available readout bandwidth and to minimize the effect of non-linearities, the LC resonators are usually designed to be on a regular grid. The lithographic processes, however, pose a limit on the accuracy of the effective filter resonance frequencies. Off-resonance bias carriers could be used to suppress the impact of intermodulation distortions, which, nonetheless, would significantly affect the effective bias circuit and the detector spectral performance. In this paper, we present a frequency shift algorithm (FSA) to allow off-resonance readout of TESs, while preserving the on-resonance bias circuit and spectral performance, demonstrating its application to the FDM readout of an x-ray TES microcalorimeter array. We discuss the benefits in terms of mitigation of the impact of intermodulation distortions at the cost of increased bias voltage and the scalability of the algorithm to multi-pixel FDM readout. We show that with FSA, in the multi-pixel and frequencies shifted on-grid, the line noises due to intermodulation distortion are placed away from the sensitive region in the TES response and the x-ray performance is consistent with the single-pixel, on-resonance level.

Efficacy of Osimertinib Plus Bevacizumab vs Osimertinib in Patients With EGFR T790M-Mutated Non-Small Cell Lung Cancer Previously Treated With Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitor: West Japan Oncology Group 8715L Phase 2 Randomized Clinical Trial

Importance

Although treatment with first-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) plus antiangiogenic inhibitor has shown promising efficacies in patients with EGFR-mutated lung adenocarcinoma, recent single-arm studies have suggested that osimertinib plus antiangiogenic inhibitor might not work synergistically.

Objective

To explore the efficacy and safety of osimertinib plus bevacizumab compared with osimertinib alone in patients with lung adenocarcinoma with EGFR T790M mutation.

Design, Setting, and Participants

Patients with advanced lung adenocarcinoma that progressed with prior EGFR-TKI treatment (other than third-generation TKI) and acquired EGFR T790M mutation were enrolled. This study comprises a lead-in part with 6 patients and a subsequent phase 2 part. In phase 2, patients were randomized to osimertinib plus bevacizumab or osimertinib alone in a 1:1 ratio.

Interventions

The combination arm received oral osimertinib (80 mg, every day) plus intravenous bevacizumab (15 mg/kg, every 3 weeks) until progression or unacceptable toxic effects. The control arm received osimertinib monotherapy.

Main Outcomes and Measures

The primary end point was progression-free survival (PFS) assessed by investigators. Secondary end points consisted of overall response rate, time to treatment failure, overall survival, and safety.

Results

From August 2017 through September 2018, a total of 87 patients were registered (6 in the lead-in part and 81 in the phase 2 part [intention-to-treat population]). Among those randomized, the median (range) age was 68 (41-82) years; 33 (41%) were male; 37 (46%) had an Eastern Cooperative Oncology Group performance status of 0; and 21 (26%) had brain metastasis. Although the overall response rate was better with osimertinib plus bevacizumab than osimertinib alone (68% vs 54%), median PFS was not longer with osimertinib plus bevacizumab (9.4 months vs 13.5 months; adjusted hazard ratio, 1.44; 80% CI, 1.00 to 2.08; P = .20). Median time to treatment failure was also shorter in the combination arm vs the osimertinib arm (8.4 months vs 11.2 months; P = .12). Median overall survival was not different in the combination arm vs osimertinib arm (not reached vs 22.1 months; P = .96). In the combination arm, common adverse events of grade 3 or higher were proteinuria (n = 9; 23%), hypertension (n = 8; 20%).

Conclusions and Relevance

In this randomized clinical trial comparing osimertinib plus bevacizumab vs osimertinib alone, the combination arm failed to show prolongation of PFS in patients with advanced lung adenocarcinoma with EGFR T790M mutation.

Trial Registration

UMIN Clinical Trials Registry Identifier: UMIN000023761.

Abstract GS1-06: FGFR1 associates with gene promoters and regulates gene transcription: Implications for endocrine resistance in ER+/FGFR1-amplified breast cancer

Background: FGFR1 amplification occurs in ~ 15% of ER+ breast cancers. In these tumors, nuclear FGFR1 has been shown to interact with DNA, but its role in transcriptional regulation is unclear. Thus, we investigated the genomic role of FGFR1 in ER+/FGFR1-amplified breast cancer. Results: FGFR1 ChIP-Seq detected 4,412 DNA binding sites in CAMA1 ER+/FGFR1-amplified breast cancer cells cultured in estrogen-free conditions. Of these binding sites, 67% were enriched at promoter regions. ChIP-qPCR confirmed FGFR1 binding to several promoter regions in a second ER+/FGFR1-amplified cell line, MDA-MB-134, and a patient derived xenograft, HCI-011. To determine the nuclear FGFR1 interactome, we performed FLAG immunoprecipitation of mixed nuclear and chromatin fractions of CAMA1 cells transduced with a 3XFLAG-FGFR1 plasmid, followed by mass spectrometry (MS) of FLAG antibody pulldowns. MS revealed RNA Polymerase II subunits among the top nuclear FGFR1 interacting proteins. FGFR1 mainly bound Pol II phosphorylated on Ser5 (Pol II S5P), a marker of transcription initiation, in CAMA1, MDA-MB-134 and HCI-011 cell extracts. Pol II S5P ChIP-Seq revealed that 2,867/4,412 (65%) FGFR1 peaks were shared with Pol II S5P. ChIP-Seq also showed that 95% of FGFR1 peaks overlapped with both H3K4me3 and H3K27ac, markers of active transcription. Consistent with these results, RNA-Seq of CAMA1 cells showed that expression of FGFR1-bound genes was markedly higher than non FGFR1-bound genes (p&lt;0.0001), suggesting that FGFR1 binds to actively transcribed genes. In addition to Pol II, MS detected FOXA1 among FGFR1 interacting proteins. ChIP-Seq analysis revealed FOXA1 enriched at FGFR1-bound loci. siRNA-mediated FOXA1 knockdown reduced FGFR1 distribution to several genomic loci in CAMA1 cells, as measured by FGFR1 ChIP-Seq, suggesting that FOXA1 mediates FGFR1 recruitment to chromatin. We next transduced MCF-7 cells with an FGFR1(SP-)(NLS) plasmid, where the NLS sequence forces nuclear import of the resulting protein. To determine the role of FGFR1 on transcriptional regulation, we used Binding and Expression Target Analysis (BETA), integrating FGFR1 ChIP-Seq and RNA-Seq results from MCF7FGFR1(SP-)(NLS) vs MCF7EV cells. This analysis predicted a direct role for genomic-bound FGFR1 in activating gene expression (p=8.01e-6). MCF7FGFR1(SP-)(NLS) cells were markedly less sensitive to fulvestrant compared to control cells. Gene Set Enrichment Analysis (GSEA) of the 1,009 genes upregulated in MCF7FGFR1(SP-)(NLS) cells and bound by FGFR1 at a genomic level revealed a strong enrichment of estrogen response early (q=2.2e-44) and late (q=6.4e-33) genes, suggesting that nuclear FGFR1 induces an ERα-associated transcriptional profile that may contribute to endocrine resistance. Finally, an expression signature associated with nuclear FGFR1 correlated with endocrine resistance in three cohorts of patients with ER+ breast cancer treated with aromatase inhibitors. We next studied the effect of growth factor stimulation on FGFR1 transcriptional function. Stimulation with FGF2 enhanced nuclear FGFR1 import in CAMA1 cells, as well as FGFR1-Pol II S5P association. Notably, these effects were not abrogated by treatment with the FGFR1 inhibitor erdafitinib. ChIP-Seq revealed that erdafitinib did not impair the FGFR1 genomic distribution. These results do not support a causal link between the FGFR1 activated TK and the receptor’s activity in the nucleus. Conclusions: We have demonstrated a role for nuclear FGFR1 in transcriptional regulation in breast cancer. FGFR1-induced gene expression contributes to endocrine resistance and is not affected by FGFR TKIs. These findings provide a rationale for developing treatment strategies to inhibit nuclear FGFR1 in ER+/FGFR1-amplified breast cancer.

Citation Format: Alberto Servetto, Rahul Kollipara, Luigi Formisano, Chang-Ching Lin, Kyung-min Lee, Dhivya R Sudhan, Ariella B Hanker, Sumanta Chatterjee, Angel Guerrero-Zotano, Paula Gonzalez-Ericsson, Saurabh Mendiratta, Hiroaki Akamatsu, Nicholas James, Ralf Kittler, Carlos L Arteaga. FGFR1 associates with gene promoters and regulates gene transcription: Implications for endocrine resistance in ER+/FGFR1-amplified breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS1-06.

Phase Ib Study of Osimertinib Plus Ramucirumab in Japanese Lung Cancer Patients With EGFR Mutation

BACKGROUND/AIM

To explore the safety of osimertinib plus ramucirumab in patients with EGFR-mutated lung adenocarcinoma.

PATIENTS AND METHODS

Six advanced lung adenocarcinoma patients with EGFR mutation were treated with osimertinib 80 mg/day plus ramucirumab 10 mg/kg, every two weeks. Defined dose-limiting toxicity (DLT) was assessed within the first two treatment cycles.

RESULTS

Of those enrolled, five patients had both EGFR exon 20 T790M mutation and sensitizing mutation. DLT was observed in one patient (grade 3 appetite loss). During the entire period, no other severe adverse event was observed. Five patients showed partial response and one disease progression. Median progression-free survival for patients with EGFR T790M was 9.2 months. In an exploratory analysis, changes of cell-free DNA at 2 weeks predicted radiological tumor responses.

CONCLUSION

The safety results of osimertinib plus ramucirumab in Japanese lung adenocarcinoma patients with EGFR mutation will lead to further efficacy investigation.

Performance and uniformity of a kilo-pixel array of Ti/Au transition-edge sensor microcalorimeters

Uniform large transition-edge sensor (TES) arrays are fundamental for the next generation of x-ray space observatories. These arrays are required to achieve an energy resolution ΔE < 3 eV full width at half maximum (FWHM) in the soft x-ray energy range. We are currently developing x-ray microcalorimeter arrays for use in the future laboratory and space-based x-ray astrophysics experiments and ground-based spectrometers. In this contribution, we report on the development and the characterization of a uniform 32 × 32 pixel array with 140 × 30 μm² Ti/Au TESs with the Au x-ray absorber. We report on extensive measurements on 60 pixels in order to show the uniformity of our large TES array. The averaged critical temperature is T_c = 89.5 ± 0.5 mK, and the variation across the array (∼1 cm) is less than 1.5 mK. We found a large region of detector's bias points between 20% and 40% of the normal-state resistance where the energy resolution is constantly lower than 3 eV. In particular, results show a summed x-ray spectral resolution ΔE_FWHM = 2.50 ± 0.04 eV at a photon energy of 5.9 keV, measured in a single-pixel mode using a frequency domain multiplexing readout system developed at SRON/VTT at bias frequencies ranging from 1 MHz to 5 MHz. Moreover, we compare the logarithmic resistance sensitivity with respect to temperature and current (α and β, respectively) and their correlation with the detector's noise parameter M, showing a homogeneous behavior for all the measured pixels in the array.

A phase II study of cisplatin plus vinorelbine combined with atezolizumab as adjuvant therapy for completely resected non-small-cell lung cancer with EGFR mutation (West Japan Oncology Group 11719L/ADJUST study)

Background

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) is a standard treatment in EGFR-mutated advanced non-small-cell lung cancer (NSCLC); however, previous data have suggested that EGFR-TKI has limited potential as adjuvant therapy. On the contrary, based on subset analysis with the immune checkpoint inhibitor (ICI) plus platinum-doublet chemotherapy in advanced NSCLC with EGFR mutation, we hypothesized that this combination was worth testing as adjuvant therapy in patients with EGFR-mutated NSCLC.

Methods

Herein, we introduce our phase II study of cisplatin plus vinorelbine combined with atezolizumab as adjuvant therapy for completely resected NSCLC with EGFR mutation. Accrued patients will be pathological stage II-IIIA with completely resected NSCLC and whose tumors have EGFR mutation. Treatment comprises four cycles of cisplatin plus vinorelbine combined with atezolizumab followed by maintenance with atezolizumab. The primary endpoint is the disease-free survival (DFS) rate at 2 years. Secondary endpoints are DFS, overall survival, and safety. In total, 18 patients will be enrolled in this study.

Discussion

Ongoing phase III trials of adjuvant ICI allow the inclusion of patients with EGFR mutation, but our current trial will provide the earliest clinical data on the efficacy of platinum-doublet chemotherapy with atezolizumab.