Dana-Farber Cancer Institute

Mutations in nucleophosmin 1 (NPM1) are diseased‐defining genetic alterations encountered in approximately one‐third of cases of acute myeloid leukemia (AML). A mutation in NPM1 confers a more favorable prognosis; however, clinical outcomes of NPM1–mutated AML (NPM1mut AML) are diverse due to the heterogeneity of disease biology, patient characteristics, and treatment received. Research over the last two decades has dramatically expanded our understanding of the biology of NPM1mut AML and led to the development of new therapeutic approaches and strategies for monitoring measurable residual disease (MRD). Here, we review NPM1mut AML with a practical focus on the current treatment landscape, the role of MRD in guiding management, and emerging therapies, including menin inhibitors.

Sacituzumab govitecan (SG), a Trop-2-directed antibody-drug conjugate, is currently approved to treat metastatic triple-negative breast cancer and HR+/HER2– breast cancer, and is under clinical investigation for a range of other tumor types. This review describes its mode of action, development, and clinical outcomes. SG is composed of SN-38 (a topoisomerase I inhibitor derived from irinotecan) covalently linked to an anti-Trop-2 monoclonal antibody (sacituzumab; hRS7) via a hydrolysable CL2A linker. SN-38 was chosen due to its potent antitumor activity; CL2A occupies the most effective position on SN-38 for maintaining stability during transport, with pH-sensitive payload release in the tumor, and the antigen target (Trop-2) is highly expressed on many solid tumors. SG has an ~8:1 drug-to-antibody ratio and delivers therapeutic SN-38 concentration to Trop-2+ expressing tumor cells via rapid internalization and efficient payload release. Free SN-38 can subsequently enter the tumor microenvironment and kill adjacent tumor cells with or without Trop-2 expression (bystander effect). SN-38 induces DNA breakage and inhibits nucleic acid synthesis via a drug-induced topoisomerase 1:DNA complex that interferes with cell proliferation, causing apoptosis. Dose-finding studies support SG 10 mg/kg on days 1 and 8 of a 21-day cycle as the monotherapy dose for clinical use; this was determined by therapeutic index improvement based on efficacy and safety. Payload-linker dynamics and SG potency ensure continued tissue penetration. Neutropenia and diarrhea are the most common grade ≥ 3 treatment-emergent adverse events with SG, but they are manageable. Efficacy of SG has been demonstrated across a broad spectrum of solid tumors.

A critical goal in functional genomics is evaluating which non-coding elements contribute to gene expression, cellular function, and disease. Functional characterization remains a challenge due to the abundance and complexity of candidate elements. Here, we develop a CRISPRi-based approach for multi-locus screening of putative transcription factor binding sites with a single truncated guide. A truncated guide with hundreds of sequence match sites can reliably disrupt enhancer activity, which expands the targeting scope of CRISPRi while maintaining repressive efficacy. We screen over 13,000 possible CTCF binding sites with 24 guides at 10 nucleotides in spacer length. These truncated guides direct CRISPRi-mediated deposition of repressive H3K9me3 marks and disrupt transcription factor binding at most sequence match target sites. This approach can be a valuable screening step for testing transcription factor binding motifs or other repeated genomic sequences and is easily implemented with existing tools.

Enzalutamide is a potent second-generation antiandrogen commonly used to treat hormone-sensitive and castration-resistant prostate cancer (CRPC) patients. While initially effective, the disease almost always develops resistance. Given that many enzalutamide-resistant tumors lack specific somatic mutations, there is strong evidence that epigenetic factors can cause enzalutamide resistance. To explore how resistance arises, we systematically test all epigenetic modifiers in several models of castration-resistant and enzalutamide-resistant prostate cancer with a custom epigenetic CRISPR library. From this, we identify and validate SMARCC2, a core component of the SWI/SNF complex, that is selectivity essential in enzalutamide-resistant models. We show that the chromatin occupancy of SMARCC2 and BRG1 is expanded in enzalutamide resistance at regions that overlap with CRPC-associated transcription factors that are accessible in CRPC clinical samples. Overall, our study reveals a regulatory role for SMARCC2 in enzalutamide-resistant prostate cancer and supports the feasibility of targeting the SWI/SNF complex in late-stage PCa.

Background Pembrolizumab monotherapy is an established front-line treatment for advanced non-small cell lung cancer (NSCLC) with programmed cell death-ligand 1 (PD-L1) tumor proportion score (TPS)≥50%. However, real-world data on its long-term efficacy remains sparse. Methods This study assessed 5-year outcomes of first-line pembrolizumab monotherapy in a large, multicenter, real-world cohort of patients with advanced NSCLC and PD-L1 TPS≥50%, referred to as Pembro-real 5Y. Individual patient-level data (IPD) from the experimental arm of the KEYNOTE-024 trial were extracted (KN024 IPD cohort) to compare the long-term outcomes between the two cohorts. To further assess the reproducibility of clinical trial results, we reconstructed the “KN024 look-alike” cohort by excluding patients with an Eastern Cooperative Oncology Group-performance status (ECOG-PS)≥2, those requiring corticosteroids with doses ≥10 mg of prednisolone/equivalent, patients with positive/unknown epidermal growth factor receptor/anaplastic lymphoma kinase genotype, and those with pre-existing autoimmune disease. We additionally provided a hierarchical organization of determinants of long-term benefit through a conditional inference tree analysis. Results The study included 1050 patients from 61 institutions across 14 countries, with a median follow-up of 70.3 months. The 5-year survival rate was 26.9% (95% CI: 23.8% to 30.2%), and median OS was 21.8 months (95% CI: 19.1 to 25.7), while 32 (3.0%) patients who achieved a complete response remained progression-free at the data cut-off. The KN024 look-alike cohort had a 5-year survival rate of 29.3% (95% CI: 25.5% to 33.6%) and a median OS of 27.5 months (95% CI: 22.8 to 31.3). Neither the overall study population nor the KN024 look-alike cohort exhibited significantly different OS compared with the KN024 IPD cohort. By the data cut-off, 1015 patients (96.7%) had permanently discontinued treatment: 659 (64.9%) due to progressive disease, 156 (15.4%) due to toxicity, 77 (7.6%) due to treatment completion, and 106 (10.4%) due to other reasons. Overall, 222 participants (21.1%) were treated for a minimum period of 24 months, among them the 5-year survival rates were: 31.7%, 72.7%, 78.6%, 84.2% for patients who discontinued treatment due to progressive disease, toxicity, treatment completion, and other reasons, respectively. Conclusion This study provides valuable real-world evidence that confirms the long-term efficacy of pembrolizumab outside of clinical trials. Hierarchical organization indicates ECOG-PS, age and PD-L1-TPS as the most important predictors of 5-year survival, potentially informing clinical practice.

Purpose: This study explored the combination of FAP-IL2v, a novel immune-cytokine, with pembrolizumab in patients with advanced and/or metastatic melanoma. Patients and Methods: This open-label, multicenter, phase 1b clinical study (NCT03875079) evaluated the safety, tolerability, pharmacodynamics, pharmacokinetics (PK), and antitumor activity of FAP-IL2v (simlukafusp alfa, RO6874281) in combination with pembrolizumab. Patients with advanced and/or metastatic melanoma were either checkpoint inhibitor (CPI)-naïve or -experienced. Patients received 10 mg FAP-IL2v either continuously once every three weeks (Q3W) or in an induction/maintenance setting consisting of a 3-week induction phase with weekly (QW) dosing followed by continuous Q3W dosing. Pembrolizumab was dosed Q3W at 200 mg. Results: Eighty-three patients were treated, 16 patients in two safety run-in cohorts, and 67 patients in two extension cohorts; 75 (90.4%) patients were CPI-experienced. The PK of FAP-IL2v in combination with pembrolizumab was similar to that after administration as monotherapy. Consistent with the proposed mode-of-action, FAP-IL2v preferentially expanded NK and CD8 T cells. The most common FAP-IL2v-related grade 3/4 AEs were lymphopenia (23%), elevated γ‑glutamyltransferase (8%), elevated alanine aminotransferase (6%), and infusion-related reaction (6%). A response was observed in 5 of 75 (6.7%) CPI-experienced patients (all partial responses) and in 2 of 8 CPI-naïve patients (one complete, one partial response). The median progression-free survival was 3.1 months. Conclusions: The safety profile of FAP-IL2v in combination with pembrolizumab was manageable and consistent with the known safety profile. However, further exploration of FAP-IL2v and pembrolizumab was precluded in melanoma patients with prior CPI due to the lack of clinical activity.

Importance As US society ages and the climate changes, extreme outdoor heat may exacerbate the health burden of Alzheimer disease and related dementias (ADRD), but where, when, and among whom extreme heat may increase hospitalizations with ADRD remains understudied. Objective To investigate the association between extreme heat and the risk of hospitalization with ADRD, and to explore how associations differ across climates and population subgroups. Design, Setting, and Participants Population-based cohort study, using a time-stratified case-crossover design, of Medicare fee-for-service (Part A) claims from 2000 to 2018 among beneficiaries aged 65 years or older in the contiguous US; time-stratified case-crossover design implemented with distributed lag nonlinear models using conditional logistic regression. Data were analyzed from October to November 2024. Exposures Daily maximum heat index converted to percentiles of climate-specific warm season heat index distributions. Main Outcomes and Measures The main outcome was each beneficiary’s first hospitalization with an ADRD diagnosis code, and other measures were county-level climates (arid, continental, temperate, or tropical). Results The sample included 3 329 977 beneficiaries (2 126 290 [63.9%] female, 33 887 [1.0%] Asian, 354 771 [10.7%] Black, 61 515 [1.8%] Hispanic, 2 831 391 [85.0%] White, and 891 815 [26.8%] dual eligible for Medicaid). The odds ratio (OR) of hospitalization with ADRD comparing days in the 99th vs 50th percentile of the heat index distribution was 1.02 (95% CI, 1.01-1.02), corresponding to 0.8 (95% CI, 0.5-1.1) additional hospitalizations with ADRD per 1000 beneficiaries. Results suggest extreme heat associations persist for 3 days beyond the initial day. The cumulative OR of hospitalization with ADRD after 4 days of continuous exposure to heat indexes at the 99th vs 50th percentile was 1.04 (95% CI, 1.03-1.04), or 1.7 (95% CI, 1.3-2.0) additional hospitalizations with ADRD per 1000 beneficiaries. Extrapolating these estimates to the 6.7 million adults currently living with ADRD suggests that each day of extreme heat could contribute to at least 5360 added hospitalizations with ADRD nationwide. Effects estimates were similar in temperate and continental climates. Arid and tropical climate estimates were somewhat similar but more uncertain. OR point estimates for hospitalization from 4 days of continuous extreme heat exposure for beneficiaries identifying as Asian (OR, 1.09; 95% CI, 1.02-1.17), Black (OR, 1.07; 95% CI, 1.05-1.10), and Hispanic (OR, 1.08; 95% CI, 1.03-1.13), were 2.6 to 3.2 times larger than for White beneficiaries (OR, 1.03; 95% CI, 1.02-1.04). Conclusions and Relevance This study found that extreme heat may pose a growing threat to older adults living with ADRD. This threat may be larger among Asian, Black, and Hispanic racial and ethnic groups. Clinicians should consider counseling patients living with ADRD on extreme heat risks, and policymakers should devise risk mitigation programs.

Background Waist circumference (WC) and its allometric counterpart, “a body shape index” (ABSI), are risk factors for colorectal cancer (CRC); however, it is uncertain whether associations with these body measurements are limited to specific molecular subtypes of the disease. Methods Data from 2,772 CRC cases and 3,521 controls were pooled from four cohort studies within the Genetics and Epidemiology of Colorectal Cancer Consortium. Four molecular markers (BRAF mutation, KRAS mutation, CpG island methylator phenotype, and microsatellite instability) were analysed individually and in combination (Jass-types). Multivariable logistic and multinomial logistic models were used to assess the associations of WC and ABSI with overall CRC risk and in case-only analyses evaluating heterogeneity by molecular subtype, respectively. Results Higher WC (ORper 5cm=1.06, 95%CI:1.04-1.09) and ABSI (ORper 1-SD=1.07, 95%CI:1.00-1.14) were associated with elevated CRC risk. There was no evidence of heterogeneity between the molecular subtypes. No difference was observed regarding the influence of WC and ABSI on the four major molecular markers in proximal colon, distal colon, and rectal cancer, as well as in early and later onset CRC. Associations did not differ in the Jass-type analysis. Conclusions Higher WC and ABSI were associated with elevated CRC risk; however, they do not differentially influence all four major molecular mutations involved in colorectal carcinogenesis but underscore the importance of maintaining a healthy body weight in CRC prevention. Impact The proposed results have potential utility in colorectal cancer prevention.

Sequencing of human patient tumors has identified recurrent missense mutations in genes encoding core histones. We report that mutations that convert histone H3 amino acid 50 from a glutamate to a lysine (H3E50K) support an oncogenic phenotype. Expression of H3E50K is sufficient to transform human cells as evidenced by an increase in cell migration and invasion, and an increase in proliferation and clonogenicity. H3E50K also increases the invasive phenotype in the context of co-occurring BRAF mutations, which are present in patient tumors characterized by H3E50K. H3E50 lies on the globular domain surface in a region that contacts H4 within the nucleosome. We find that H3E50K selectively increases chromatin accessibility and perturbs proximal H3 post-translational modifications including H3K27me3; together these changes to chromatin dynamics dysregulate gene expression to support the epithelial-to-mesenchymal transition. Functional studies using Saccharomyces cerevisiae reveal that, while yeast cells that express H3E50K as the sole copy of histone H3 show sensitivity to cellular stressors, including caffeine, H3E50K cells display some genetic interactions that are distinct from the characterized H3K36M oncohistone yeast model. Taken together, these data suggest that additional H3 mutations have the potential to support oncogenic activity and function through distinct mechanisms that dysregulate gene expression.

Chronic graft-versus-host disease (cGVHD) is the leading cause of morbidity and non-relapse associated mortality following allogeneic hematopoietic cell transplantation (aHSCT). Treating steroid resistant/refractory cGVHD remains challenging. Epigenetic regulators can have global transcriptional effects that control donor T-cell responses. We previously showed that inhibiting histone lysine motifs by chromatin-modifying enzymes can ameliorate murine cGVHD. Targeting donor T-cell DNA methyltransferases reduce acute GVHD. Here, we sought to investigate the DNA demethylase Tet (ten-eleven translocase) methylcytosine dioxygenases 2 (Tet2) and Tet3 in T follicular helper cell (TFH) dependent cGVHD. In a clinically relevant model of cGVHD that recapitulates pulmonary fibrosis from bronchiolitis obliterans, recipients of Tet2 deleted donor T-cells did not have improved pulmonary function tests in contrast to the markedly improved pulmonary function in Tet3 deleted donor T-cells. Tet3 deleted donor T-cells did not impair TFH-dependent germinal center (GC) formation. Unexpectedly, TET3 deficiency resulted in elevated GATA3 expression in and IL-4 production by TFH cells. TET3 deficient TFH cells supported GC B-cell immunoglobulin (Ig) class switching to nonpathogenic IgG1 but not pathogenic IgG2c allowing mice to escape cGVHD pulmonary fibrosis. Elevated GATA3 expression and disruption of IgG2c class switching was recapitulated in an in-vitro human GC culture system. These studies provide new insights into the function of Tet3 in TFH driven Ig class switching and suggest a new approach to mitigate cGVHD.

4 Background: Anti-PD-1 monotherapy has limited efficacy in patients (pts) with advanced squamous cell cancer of the anal canal (SCAC). In KN-158, pembrolizumab (P) was reported to have an ORR of 10%, DCR of 25%, and a 12-month PFS rate of 15% in patients with incurable SCAC. TGFβ promotes immunosuppression within the tumor microenvironment, and inhibition of this pathway may improve tumor susceptibility to immune checkpoint blockade.Ficerafusp alfa (F)is a bifunctional EGFR/TGFβ inhibitor with manageable safety and favorable preliminary anti-tumor efficacy in advanced solid tumors (ESMO 2022 731MO). We evaluated the combination of F+P in pts with chemotherapy-refractory locally advanced/unresectable or metastatic SCAC. Methods: This single-arm, multicenter dose expansion from an ongoing phase I/Ib trial enrolled pts with ICI-naïve SCAC that was locally advanced/unresectable or metastatic, who had received 1-2 prior lines of chemotherapy. Pts received ficerafusp alfa (1500 mg IV on days 1, 8, 15) and pembrolizumab (200 mg IV on day 1) every 21-day cycle. The primary endpoint was safety (CTCAE v5), and secondary endpoints were radiographic response (RECIST 1.1), duration of response, progression-free survival, and overall survival. Results: Among 26 pts treated, 21 (81%) were female, and median age was 61 (range: 43-82). As of 7/2024, 22 pts are evaluable for efficacy. ORR was 32% (95% CI 13.9-54.9%). Six of the seven responses were confirmed, including one pt with a radiographic PR with pathologic CR to F+P. Seven pts (32%) achieved SD as best response, resulting in DCR of 64%. Median PFS was 2.8 months (95% CI 1.4-14.8) and the PFS rate at 12 months was 36%. G3 treatment-related adverse events were observed in 10/26 pts (38%, most common: Anemia (19%) and acneiform rash (12%)). TRAEs led to permanent discontinuation of study treatment in 2 pts (8%). The most common TRAEs of any grade were acneiform rash (13/26, 50%), epistaxis (46%) and headache (38%). Conclusions: The addition of ficerafusp alfa demonstrated encouraging efficacy, with increased ORR, DCR, and 12-month PFS relative to historical precedent with pembrolizumab alone. Safety and tolerability were acceptable. Further investigation of this combination in pts with advanced SCAC is warranted. Updated data will be presented. Study funded by Bicara Therapeutics Inc. with access to pembrolizumab in collaboration with Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA (NCT04429542). Clinical trial information: NCT04429542 .

23 Background: BOT is an Fc-enhanced, multifunctional anti-CTLA−4 antibody designed to improve Fc gamma receptor-mediated effector functions and extend the reach of I-O to tumor types such as MSS mCRC. Here we present preliminary data from a randomized, open-label, phase 2 study in patients (pts) with MSS mCRC NLM treated with BOT ± BAL (anti-PD−1; NCT05608044). The study aimed to inform dose and contribution of components based on the primary endpoint of objective response rate (ORR) by RECIST 1.1 per investigator, and safety, and was not powered for statistical comparisons between arms. Methods: A total of 234 pts (intent-to-treat [ITT]) were randomized to BOT (up to 4 doses) 75 or 150 mg every 6 wks (Q6W), BOT 75 or 150 mg Q6W plus BAL 240 mg Q2W (up to 2 years), or standard of care (SOC; regorafenib or trifluridine/tipiracil). Results: Median age was 58 yrs (range 23—90), 50% male, 39% rectal, 44% 3L+, 43% ECOG 1, 58% KRAS mutant, 4% NRAS mutant, 83% prior bev, all MSS and/or pMMR by local testing. Key characteristics were well balanced with some exceptions including median time from diagnosis of metastatic disease to study entry (30 mos across arms; 45 mos SOC) and presence of peritoneal metastases (34% across arms; 42% 75 mg BOT / 240 mg BAL; 27% SOC). As of July 29, 2024, median follow-up was 9.8 mos. Key efficacy and safety data are shown (Table). Image based endpoints by blinded independent review, as well as overall survival will be reported in the future. Grade ≥3 treatment-related adverse events (TRAEs) were highest with SOC followed by BOT + BAL combination, and then BOT monotherapy, with dose dependency. Treatment-related immune-mediated diarrhea/colitis (imDC) was manageable and highest with 150 mg BOT / 240 mg BAL. No new safety signals and no treatment-related deaths occurred. Conclusions: The study met the objectives of informing dose and contribution of components. Overall ORR was higher with BOT + BAL vs BOT monotherapy. ORR was highest with 75 mg BOT / 240 mg BAL with less toxicity as compared to 150 mg BOT / 240 mg BAL. Consistent with published data, there were no objective responses in SOC whereas most responses seen with BOT + BAL were ongoing, similar to the durable responses observed in the ph1 study. These responses are differentiated from previous I-O-only combinations and SOC, supporting further investigation of 75 mg BOT / 240 mg BAL vs SOC in a planned global ph3 trial. Clinical trial information: NCT05608044 . 75 mg BOT/240 mg BAL 150 mg BOT/240 mg BAL 75 mg BOT 150 mg BOT SOC ITT (Randomized) n=62 n=61 38 n=40 n=33 ORR, % (95% CI) 19%(10—31) 8%(3—18) 0%(0—10) 8%(2—20) 0%(0—11) Safety (Treated) n=62 n=60 n=37 n=39 n=21 Any Grade TRAEs, n (%) 54 (87) 59 (98) 28 (76) 31 (79) 19 (90) Grade ≥3 TRAEs, n (%) 22 (35) 25 (42) 8 (22) 9 (23) 12 (57) Any Grade Treatment-related IMDC, n (%) 19 (31) 28 (47) 13 (35) 12 (31) 0 (0)

666 Background: In the phase 3 CABINET trial (NCT03375320), cabozantinib (CABO) significantly prolonged median progression-free survival (PFS) compared to placebo (PB) in patients with advanced, previously treated, progressive extrapancreatic NET (epNET) [HR 0.38 (95% CI, 0.25-0.59, P<0.0001)] and pancreatic NET (pNET) [HR 0.23 (95% CI, 0.12-0.42, P<0.0001)] (Chan et al., NEJM, 2024). In this analysis, we focus on outcomes of patients with epNET arising in the GI tract. Methods: Patients with locally advanced or metastatic epNET or pNET were randomized 2:1 in separate cohorts to receive CABO 60 mg daily vs PB. The epNET cohort included patients with tumors arising in the GI tract (not including pancreas), lung, unknown primary, and other rare primary sites. In this subgroup analysis of the epNET cohort, patients with GI NET were included. Eligibility included progression by RECIST within 12 months (mo) prior to registration, ≥ 1 prior systemic therapy. Primary endpoint: PFS by blinded independent central review (BICR). Secondary endpoints: objective response rate, overall survival, safety. Results: 116 of the 203 patients in the epNET cohort had GI NET (CABO, n=70; PB, n=46). Median age was 66 yrs; females: 46%; G1/G2/G3/unknown grade: 35%/57%/6%/2%. ECOG performance status: 0/1-2: 43%/57%. White race: 86%. The most common primary tumor locations were ileum/cecum (54%), small intestine with location not specified (20%); non-cecum colon or rectum (11%), stomach (4%); duodenum (3%); jejunum and nonspecified midgut site (3% each). Prior systemic therapies included somatostatin analogs (SSA) (100%), everolimus (59%); Lu-177 dotatate (77%); temozolomide +/- capecitabine (16%). In patients with GI NET, CABO was associated with improved PFS by BICR compared to PB (stratified HR, 0.50; 95% CI: 0.28-0.88, 1-sided stratified log-rank P=0.007). Median PFS with cabozantinib was 8.5 mo (95% CI, 6.0-16.7) compared to 5.6 mo (95% CI, 3.9-11.0) with PB. CABO demonstrated potential benefit in patients with midgut GI NET and across clinical factors including grade, functional status related to hormone secretion, concurrent SSA use, and prior therapy with Lu-177 dotatate or everolimus. The most frequent grade 3/4 adverse events attributed to therapy with CABO included hypertension (19%), diarrhea (13%), fatigue (10%). Conclusions: CABO is associated with improvement in PFS compared to PB in patients with advanced GI NET. Potential benefit was observed across clinical factors including grade, functional status, concurrent SSA, and prior treatment. The safety profile for CABO in patients with GI NET is consistent with that previously reported. Support: U10CA180821, U10CA180882; U10CA180820 (ECOG-ACRIN), U10CA180868 (NRG Oncology), U10CA180888 (SWOG); Exelixis; https://acknowledgments.alliancefound.org . Clinical trial information: NCT03375320 .