SMARCA4 mutation

P2, N=60, Not yet recruiting, Prelude Therapeutics

This influences essential cellular processes such as differentiation and cell cycle regulation, and SMARCA4 is widely regarded as a tumor suppressor. This review will explore the role of SMARCA4 mutations in tumor progression, its clinicopathological features in NSCLC, its impact on treatment outcomes, and potential therapeutic strategies..

This case underscores the transient efficacy of targeted therapy in SMARCA4-deficient NSCLC with concurrent EGFR mutations. It highlights the need for continuous therapeutic adjustments and emphasizes the importance of further research into effective strategies for treating this complex and challenging subset of NSCLC, as current modalities have limitations in sustained efficacy.

Despite undergoing radical surgery and receiving systemic treatments including VeIP (vinblastine, ifosfamide, cisplatin), and VDC (vincristine, doxorubicin, cyclophosphamide) regimens, the patient succumbed to death due to disease progression. With the implementation of NGS, we anticipate that more cases with SMARCA4 mutations will be diagnosed in the future. Further research is necessary to unveil therapeutic targets associated for this oncogenic alteration.

DNA-based next-generation sequencing revealed a nonsense mutation in SMARCA4, copy number loss in SMARCB1, and a nonsense mutation in ARID1A. Different molecular alterations of the switch/sucrose nonfermenting complex subunits in the present case may provide further insights into the functions of the switch/sucrose nonfermenting complex in the progression of tumors.

Multiplexed immunofluorescence on 93 NSCLC samples identified higher intratumoral CD8+PD1+ T cells (p = 0.02) in tumors with PD-L1 TPS greater than or equal to 90% versus 50% to 89%. Pembrolizumab and cemiplimab were found to have long-term survival benefit and favorable genomic and immunophenotypic profile in patients with advanced NSCLC with PD-L1 TPS greater than or equal to 90% compared with TPS 50% to 89%.

We treated the patients with combination of an immune checkpoint inhibitor (pembrolizumab) and a multikinase inhibitor (lenvatinib), and the response to the treatment was stable. This study presents the first report on the response to immune checkpoint inhibitor and multikinase inhibitor in SDUS. The online version contains supplementary material available at 10.1007/s13691-024-00721-2.

Finally, we show that YD23 has potent tumor growth inhibitory activity in SMARCA4-mutant xenografts. These findings provide the mechanistic basis for development of SMARCA2 degraders as synthetic lethal therapeutics against SMARCA4-mutant lung cancers.

We validate these results by orthogonal genetic and pharmacologic approaches by demonstrating that KD025 (Belumosudil), an FDA approved ROCK inhibitor, has highly synergistic anti-cancer activity in vitro and in vivo in combination with OXPHOS inhibition...Importantly, we found converging phosphorylation-dependent regulatory cross-talk by AMPK and ROCK kinases on key RHO GTPase signaling/ROCK-dependent substrates such as PPP1R12A, NUMA1 and PKMYT1 that are known regulators of cell cycle progression. Taken together, our study identified ROCK kinases as critical mediators of metabolic adaptation of cancer cells to OXPHOS inhibition and provides a strong rationale for pursuing ROCK inhibitors as novel combination partners to OXPHOS inhibitors in cancer treatment.

Additionally, immunotherapy efficacy in patients with SMARCA4 mutations depended on the co-mutant genes. Thus, SMARCA4 could be an important factor to be considered for LUAD diagnosis and treatment.

P1/2, N=86, Recruiting, National Cancer Institute (NCI) | Trial completion date: Sep 2025 --> Jun 2026 | Trial primary completion date: Sep 2025 --> Jun 2026

P2, N=45, Recruiting, Dana-Farber Cancer Institute | Trial primary completion date: Oct 2024 --> Jun 2025

Mutations in other SWI/SNF complex members, including SMARCA2, SMARCB1 and SMARCC1, occur rarely in either OCCC or SCCOHT. Abrogated SWI/SNF raises opportunities for pharmacological inhibition, including the use of DNA damage repair inhibitors, kinase and epigenetic inhibitors, as well as immune checkpoint blockade.

SMARCA4-Mut is an adverse prognostic feature in NSCLC patients. Napsin A expression in SMARCA4-Mut patients is associated with prolonged OS.

Finally, we show that YDR1 and YD54 synergize with the KRAS G12C inhibitor sotorasib to inhibit growth of SMARCA4 and KRAS G12C co-mutant lung cancer cells. These findings provide additional evidence for the utility of single agent or combination regimens containing SMARCA2 PROTACs as synthetic lethal therapeutics against SMARCA4 mutant cancers.

Importantly, we uncover distinct roles of the bromodomain in modulating chromatin binding/targeting in a DNA-accessibility-dependent manner, pointing to a model where successive longer-lived binding within "hotspots" leads to sustained productive remodeling. Finally, systematic comparison of six common BRG1 mutants implicated in various cancers unveils alterations in chromatin-binding dynamics unique to each mutant, shedding insight into a multi-modal landscape regulating the spatio-temporal organizational dynamics of SWI/SNF remodelers.

TEs occurred later with EGFR and ALK , while earlier with ROS1 or KRAS with STK11, KEAP1 or SMARCA4 co-mutations compared to those with KRAS mutations alone. $$table_{7740CBC2-774F-48DA-932A-077113E7FED5}$$

TEs occurred later with EGFR and ALK , while earlier with ROS1 or KRAS with STK11, KEAP1 or SMARCA4 co-mutations compared to those with KRAS mutations alone. Cumulative incidence of venous and arterial TEs % 0 6 weeks 6 months 1 year 2 years 3 years Overall 2.8 6 11.7 15.8 21.5 26.2 ALK 5.3 10.7 12 14.8 14.8 17 BRAF 2.1 5.8 12.9 16.3 19.5 27.9 EGFR 2 5.8 10.2 14 17.9 23 HER2 0 3.5 7.2 9.2 19.5 23 KRAS 2.7 5.1 11.3 15.3 22.5 27.1 MET 14 6.8 11.3 21.2 21.2 23.9 27.7 RET 13.3 23.3 33.3 36.6 44.5 50.1 ROS1 12 20 34.2 34.2 45.1 53.3

Conclusions : SMARCA4 -deficient NSCLCs has a distinct tumor immune microenvironment characterized by increased myeloid cell and macrophage infiltration, potentially contributing to resistance to immune checkpoint inhibitors. Additional work is underway to profile and spatially analyze the tumor immune microenvironment and to characterize its relation to STK11 co-mutation status.

Histologically, the tumors exhibited a sheet-like growth pattern, reduced or absent epithelial markers, and loss of BRG-1 expression, with molecular analysis confirming SMARCA4 gene mutations. The response to conventional chemotherapy was poor, underscoring the importance of complete surgical resection and the development of alternative treatment modalities.

SMARCA4 protein deficiency, rather than genetic mutations, played a decisive role in its characteristics of higher TMB and poor prognosis. Chemoimmunotherapy serves as the optimal option in the current treatment regimen. Paclitaxel-based chemoimmunotherapy performed better than those with pemetrexed-based chemoimmunotherapy.

With several patent applications disclosed recently, interest in targeting SMARCA2 should continue, especially with a selective SMARCA2 PROTAC now in the clinic from Prelude Therapeutics. The outcome of the clinical trials will influence the evolution of selective SMARCA2 PROTACs development.

P1/2, N=254, Recruiting, Haihe Biopharma Co., Ltd. | N=168 --> 254

Esophageal carcinoma with SMARCA4 mutations shows overly aggressive behavior and presents with advanced stages of disease; most patients succumb to the disease within 1 year of initial diagnosis. Esophageal carcinoma with SMARCA4 mutation is an overly aggressive disease, and further research on the affected molecular pathway may help improve its prognosis.

Our findings suggest that SMARCA4 mutation negatively affects NSCLC OS and PFS. The prognostic effects of SMARCA4-co-occurring mutations and the predictive role of SMARCA4 mutation status in immunotherapy require further exploration.

P2, N=267, Completed, Epizyme, Inc. | Active, not recruiting --> Completed | Trial completion date: Jun 2024 --> Feb 2024

Here we demonstrate that EBV- BL comprises two subsets of cases based on SOX11 expression. The mutual exclusion of SOX11 and EBV, and the association of SOX11 with a specific genetic landscape suggest a role of SOX11 in the early pathogenesis of BL.

The redoxhigh phenotype in LUAD is predominantly driven by mutations in KEAP1, STK11, NRF2, and SMARCA4. This phenotype diminishes the number of tissue-resident memory CD8+ T cells and attenuates the efficacy of ICIs.

These results serve as the first comprehensive examination of the relationship between SMARCA4ms and clinical outcomes in GEA.

AU-24118 demonstrated tumor regression in a model of castration-resistant prostate cancer (CRPC) which was further enhanced with combination enzalutamide treatment, a standard of care androgen receptor (AR) antagonist used in CRPC patients. The ABCB1 inhibitor, zosuquidar, reversed resistance to all three PROTAC degraders tested. Combined, these findings position mSWI/SNF degraders for clinical translation for patients with enhancer-driven cancers and define strategies to overcome resistance mechanisms that may arise.

Most early compounds are weakly selective, but these efforts have culminated in the first dual SMARCA2/SMARCA4 ATPase inhibitor to enter clinical trials. Data from the ongoing clinical trials, as well as continued advancement of SMARCA2-selective ATPase inhibitors, are anticipated to significantly impact the field of therapies, targeting SMARCA4-deficient tumors.

P2, N=267, Active, not recruiting, Epizyme, Inc. | Trial primary completion date: Jun 2024 --> Feb 2024

P1/2, N=168, Recruiting, Haihe Biopharma Co., Ltd. | Trial completion date: Dec 2024 --> Dec 2025 | Trial primary completion date: Dec 2023 --> Dec 2025

and Deng et al. find that loss of ARID1A or SMARCA4 contributes to lymphomagenesis by causing B cells to aberrantly re-enter germinal centers where they undergo repeated rounds of proliferation and somatic hypermutation.

Taken together, the high incidence of SMARCA4 aberrations in LCC may indicate its diagnostic and prognostic value. Our study established the necessity of SMARCA4 IHC in the identification of SMARCA4-aberrant tumours, and this may be of particular importance in LCC and tumours without known driver events.

This observation could have important implications for WNT medulloblastoma patients, who are frequently affected by both alterations with the functional role of SMARCA4 mutations in tumorigenesis not deciphered so far. Additionally, this work highlights divergence of mouse phenotypes after brain-specific activation of WNT signaling from previously published studies and proposes potential reasons for varying recombination using the brain lipid binding protein (Blbp)-cre mouse strain.

In endometrial clear cell carcinoma, we observed 8.7% of tumors with HER2 gene amplification. The HER2 immunohistochemical staining appears to be consistent with the HER2 gene amplification. It needs further cases to be validated.

Notably, mutational profiling through broad-panel NGS could more sensitively detect residual tumors than the conventional histologic methods. Adjuvant CT and adjuvant CRT exhibited no significant difference in eliminating locoregional recurrence risk for stage pIIIA/N2 NSCLC patients with molecularly positive surgical margins.

Thoracic SMARCA4-UTs exhibited an aggressive clinical course, presented solid architecture with or without necrosis and/or rhabdoid morphology, and frequently expressed CD34 and synaptophysin. Some thoracic SMARCA4-UTs appear to be associated with responsiveness to immunotherapy, suggesting the need for validation in larger series.

This tumor thus warrants careful consideration. Accurate diagnosis can greatly improve early diagnosis and treatment of these tumors.

It is necessary to identify this subset of lung adenocarcinoma by carrying out BRG1 stain routinely on lung adenocarcinoma. These patients can then be identified and benefit from targeted therapies.

P1, N=22, Active, not recruiting, Prelude Therapeutics | Recruiting --> Active, not recruiting | N=61 --> 22