A case study of Duchenne muscular dystrophy caused by Alu element insertion in DMD gene and analysis of its gray-hair symptoms.

Duchenne muscular dystrophy (DMD) is a severe X-linked recessive genetic disorder caused by mutations in the DMD gene, which leads to a deficiency of the dystrophin protein. The main mutation types of this gene include exon deletions and duplications, point mutations, and insertions. These mutations disrupt the normal expression of dystrophin, ultimately leading to the disease. In this study, we reported a case of DMD caused by an insertion mutation in exon 59 (E59) of the DMD gene. The affected child exhibited significant abnormalities in related biochemical markers, early symptoms of DMD, and multiple gray hair. His mother and sister were carriers with slightly abnormal biochemical markers. The mother had mild clinical symptoms, while the sister had no clinical symptoms. Other family members were genetically and physically normal. Sequencing and sequence alignment revealed that the inserted fragment was an Alu element from the AluYa5 subfamily. This insertion produced two stop codons and a polyadenylate (polyA) tail. To understand the impact of this insertion on the DMD gene and its association with clinical symptoms, exonic splicing enhancer (ESE) prediction indicated that the insertion did not affect the splicing of E59. Therefore, we speculated that the insertion sequence would be present in the mRNA sequence of the DMD gene. The two stop codons and polyA tail likely terminate translation, preventing the production of functional dystrophin protein, which may be the mechanism leading to DMD. In addition to typical DMD symptoms, the child also exhibited premature graying of hair. This study reports, for the first time, a case of DMD caused by the insertion of an Alu element into the coding region of the DMD gene. This finding provides clues for studying gene mutations induced by Alu sequence insertion and expands the understanding of DMD gene mutations.

Brugada syndrome in a patient with AKAP9 mutation: Case report and review of the literature.

Brugada syndrome (BrS) is a rare autosomal dominant inherited channel disorder characterized by a specific electrocardiographic pattern of right precordial ST-segment elevation. Clinically, patients may experience polymorphic ventricular tachycardia and ventricular fibrillation, leading to recurrent syncope and sudden cardiac death (SCD) in the absence of structural cardiomyopathy. The A-kinase anchor protein 9 (AKAP9) gene, located on chromosome 7, encodes the AKAP9 protein, which plays a crucial role in regulating the phosphorylation of slowly activating delayed rectifier potassium channels (IKs). Here, we present a rare case of BrS associated with an insertion mutation in AKAP9, resulting in a frameshift mutation.

A phase II study of osimertinib in patients with NSCLC harboring EGFR exon 20 insertion: A multicenter trial of the Korean Cancer Study Group (LU17-19).

BACKGROUND: Epidermal growth factor receptor (EGFR) exon 20 insertions account for up to 10% of all EGFR mutations. Clinical outcomes in patients receiving approved EGFR exon 20 insertion-specific inhibitors have been variable. Although osimertinib has demonstrated antitumor activity in clinical trials, its clinical efficacy and translational potential remain to be determined in non-small cell lung carcinoma (NSCLC) with EGFR exon 20 insertion. METHODS: In this multicenter phase II study, patients with advanced NSCLC harboring EGFR exon 20 insertions for whom the standard chemotherapy failed received 80 mg osimertinib once daily. The primary endpoint was the investigator-assessed objective response rate (ORR) as defined by Response Evaluation Criteria in Solid Tumors version 1.1. The secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety profile. RESULTS: Among 15 patients enrolled at stage 1, the best response was most commonly disease stabilization (73.3 %), which did not meet the stage 1 threshold (objective response ≥ 2/15). As of data cutoff, two patients remained on the treatment. The median PFS and OS were 3.8 (95 % confidence interval [CI] = 1.7-5.5) months and 6.5 (95 % CI = 3.9-not reached) months, respectively. Adverse events (≥grade 3) were anemia, hypercalcemia, and pneumonia (13.3 % each), and asthenia, femur fracture, increased alkaline phosphate, hyperkalemia, bone pain, and azotemia (6.7 % each). Pre-existing EGFR C797S mutation detected in plasma limited the efficacy of osimertinib. CONCLUSION: Osimertinib at 80 mg once daily had limited efficacy and mostly showed disease stabilization with an acceptable safety profile in advanced NSCLC harboring EGFR exon 20 insertions. CLINICALTRIALS: govIdentifier: NCT03414814.

A phase 1 study to assess the absolute bioavailability, mass balance, pharmacokinetics, metabolism, and excretion of [14C]-mobocertinib, an oral inhibitor of EGFR exon 20 insertion mutations, in healthy participants.

Mobocertinib (TAK-788) is a first-in-class oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that received accelerated approval for the treatment of patients with non-small cell lung cancer with EGFR exon 20 insertion mutations previously treated with platinum-based chemotherapy. This phase 1, 2-period, study was conducted to assess the absolute bioavailability of mobocertinib (Period 1), as well as mass balance, pharmacokinetics, metabolism, and excretion of [14C]-mobocertinib (Period 2) in healthy adult males. In Period 1, participants received a single oral capsule dose of 160 mg mobocertinib, followed by a 15-minute intravenous infusion of 50 µg (~ 2 µCi) [14C]-mobocertinib administered from 3.75 to 4 h after the capsule dose. In Period 2, a single oral dose of 160 mg (~ 100 µCi) [14C]-mobocertinib was administered as an oral solution. The geometric mean absolute bioavailability of mobocertinib was determined to be 36.7%. After oral administration of [14C]-mobocertinib, mobocertinib and its active metabolites, AP32960 and AP32914, were minor components in plasma, accounting for only 0.275% of total plasma radioactivity as the majority of mobocertinib-related material was covalently bound to plasma proteins. The geometric mean percentage of the administered radioactive dose recovered in the urine and feces was 3.57% and 76.0%, respectively. Only 0.39% of the oral dose of [14C]-mobocertinib was recovered in the urine as mobocertinib; thus, indicating that renal excretion of unchanged drug was a very minor pathway of elimination. In both treatment periods, mobocertinib was generally safe and well-tolerated as all adverse events were Grade 1 in severity. (Trial registration number ClinicalTrials.gov NCT03811834. Registration date January 22, 2019).

Clinical outcomes in patients with non-small cell lung cancer harboring EGFR Exon20 in-frame insertions in the near-loop and far-loop: Results from LC-SCRUM-Asia.

OBJECTIVES: In this study, we explored the clinical outcomes of non-small cell lung cancer (NSCLC) patients with EGFR Exon20 in-frame insertions (Exon20ins), and the impact of the location of Exon20ins on these clinical outcomes. MATERIALS AND METHODS: The efficacies of current systemic therapies in NSCLC patients harboring Exon20ins were investigated using a large-scale clinico-genomic database of LC-SCRUM-Asia, and compared with that of amivantamab in the CHRYSALIS trial. RESULTS: Of the 11,397 patients enrolled in LC-SCRUM-Asia, Exon20ins were detected in 189 patients (1.7 %). Treatment with classical EGFR tyrosine-kinase inhibitors (classical TKIs) was associated with a significantly shorter progression-free survival (PFS) in NSCLC patients with Exon20ins as compared with Exon19 deletions and L858R. Post platinum-based chemotherapy, classical TKIs and immune checkpoint inhibitors (ICIs) were associated with a shorter PFS than with docetaxel in patients with Exon20ins (HR [95 % CI]; TKIs vs docetaxel, 2.16 [1.35-3.46]; ICIs vs docetaxel, 1.49 [1.21-1.84]). Patients treated with amivantamab in the CHRYSALIS trial showed a risk reduction in PFS and overall survival as compared with LC-SCRUM-Asia patients treated with docetaxel, classical TKIs, or ICIs. Among the 189 patients, Exon20ins were classified as near-loop or far-loop insertions in 115 (61 %) and 56 (30 %) patients, respectively. Treatment with osimertinib was associated with a longer PFS in patients with Exon20ins in near-loop as compared with far-loop (median, 5.6 vs. 2.0 months; HR [95 % CI], 0.22 [0.07-0.64]). CONCLUSIONS: After platinum-based chemotherapy, classical TKIs and ICIs are less effective in NSCLC patients with Exon20ins, and amivantamab may be a promising targeted therapy. There is a possibility that the location of Exon20ins has an impact on the efficacy of TKIs.

[First-line Treatment with Furmonertinib Mesylate in Lung Adenocarcinoma Patient 
with EGFR Exon 20 Insertion Mutantion].

With the continuous innovation of genomics, proteomics and molecular biological detection technology, the treatment of non-small cell lung cancer (NSCLC) has changed from traditional chemotherapy to immunotherapy and targeted therapy. Among them, molecular tumor markers targeting tyrosine kinase pathways play more important roles in clinical practice. For advanced NSCLC patients with positive epidermal growth factor receptor (EGFR) mutations, there are many first-line drugs on the market and they could bring significant efficacy, thus completely subverting the treatment pattern of advanced NSCLC. Common mutations of EGFR in Chinese patients are located on exons 19, 20 and 21, of which exons 19 and 21 mutations are the more common types. Besides, there is also a subtype of EGFR mutations, known as EGFR 20 exon insertion (EGFR 20ins) mutation. The authors summarized the treatment of a lung adenocarcinoma patient with EGFR 20ins mutation accepting Furmonertinib mesylate, in order to provide effective references for clinical diagnosis and treatment.
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First-in-human phase I study of BEBT-109 in previously treated EGFR exon 20 insertion-mutated advanced non-small cell lung cancer.

BACKGROUND: BEBT-109 is an oral pan-mutant-selective inhibitor of epidermal growth factor receptor (EGFR) that demonstrated promising antitumor potency in preclinical models. METHODS: This first-in-human study was a single-arm, open-label, two-stage study. Phase Ia dose-escalation study evaluated the safety and pharmacokinetics of BEBT-109 in 11 patients with EGFR T790M-mutated advanced non-small cell lung cancer (aNSCLC). Phase Ib dose-expansion study evaluated the safety and efficacy of BEBT-109 in 18 patients with EGFR exon 20 insertion (ex20ins)-mutated treatment-refractory aNSCLC. The primary outcomes were adverse events and antitumor activity. Clinical trial registration number CTR20192575. FINDINGS: The phase Ia study demonstrated no dose-limiting toxicity, no observation of the maximum tolerated dose, and no new safety signals with BEBT-109 in the dose range of 20-180 mg/d, suggesting that BEBT-109 had an acceptable safety profile among patients with EGFR T790M-mutated aNSCLC. Plasma pharmacokinetics of BEBT-109 showed a dose-proportional increase in the area under the curve and maximal concentration, with no significant drug accumulation. The dose-expansion study demonstrated that BEBT-109 treatment was tolerable across the three dose levels. The three most common treatment-related adverse events were diarrhea (100%; 22.2% ≥Grade 3), rash (66.7%; 5.6% ≥Grade 3), and anemia (61.1%; 0% ≥Grade 3). The objective response rate was 44.4% (8 of 18). Median progression-free survival was 8.0 months (95% confidence intervals, 1.33-14.67). CONCLUSION: Preliminary findings showed that BEBT-109 had an acceptable safety profile and favorable antitumor activity in patients with refractory EGFR ex20ins-mutated aNSCLC. FUNDING: National Natural Science Foundation of China.

Prognostic outcomes and recurrence patterns in resected stage I lung adenocarcinoma harbouring atypical epidermal growth factor receptor mutations.

OBJECTIVES: Limited data exist on the characteristics of atypical epidermal growth factor receptor (EGFR) mutations in early-stage lung cancer. Our goal was to elucidate the associations with outcomes and recurrence patterns in resected stage I lung adenocarcinoma harbouring atypical EGFR mutations. METHODS: Eligible patients between 2014 and 2019 were retrospectively identified and grouped into exon20 insertion mutations and major atypical mutations, which included G719X, L861Q and S768I. Disease-free survival (DFS) was evaluated in the entire cohort and stratified by radiologic characteristics. Recurrence patterns were investigated and compared between groups. A competing risk model was used to estimate the cumulative incidence of recurrence. RESULTS: A total of 710 patients were finally included. Among them, 289 (40.7%) patients had exon 20 insertion mutations and 421 (59.3%) patients had major atypical mutations. There was no significant difference regarding DFS (P = 0.142) between groups in the entire cohort. The interaction between mutation subtype and the presence of ground-glass opacities was significant (hazard ratio 2.00, 95% confidence interval 1.59-2.51, P < 0.001), indicating DFS between exon 20 insertion mutations and major atypical mutations may be different among subsolid and solid tumours. Survival analysis consistently revealed no significant difference in subsolid tumours (P = 0.680), but favourable DFS of exon 20 insertion mutations in solid tumours (P = 0.037). Furthermore, patients with exon 20 insertion mutations had a lower risk of developing bone metastases did those with radiologic solid tumours (Gray's test, P = 0.012). CONCLUSIONS: Exon 20 insertion mutations were correlated with favourable DFS and lower incidence of bone metastases in radiologic solid lung adenocarcinomas harbouring atypical EGFR mutations.

Efficacy of Mobocertinib and Amivantamab in Patients With Advanced Non-Small Cell Lung Cancer With EGFR Exon 20 Insertions Previously Treated With Platinum-Based Chemotherapy: An Indirect Treatment Comparison.

INTRODUCTION: Exon 20 insertions (ex20ins) mutations of the EGFR gene account for 1% to 2% of all non-small-cell lung cancers (NSCLCs). Targeted therapies have been developed to treat this cancer type but have not been studied in head-to-head trials. Our objective was to use a matching-adjusted indirect comparison (MAIC) to assess the efficacy of mobocertinib and amivantamab in patients with NSCLC EGFR ex20ins mutations who were previously treated with platinum-based chemotherapy. MATERIALS AND METHODS: An unanchored MAIC was conducted to estimate the treatment effects of mobocertinib and amivantamab using individual-level data from the mobocertinib phase I/II single-arm trial (NCT02716116) and published data from the amivantamab single-arm CHRYSALIS trial (NCT02609776). Confirmed overall response rate (cORR), progression-free survival (PFS), overall survival (OS), and duration of response (DoR) were assessed. RESULTS: Both trials were comparable in terms of study population, study design, and outcome definitions and included 114 patients who received mobocertinib and 114 patients who received amivantamab. After MAIC weighting, all reported baseline characteristics were balanced between mobocertinib and amivantamab. The weighted odds ratio (OR) [95% confidence interval (CI)] comparing mobocertinib to amivantamab was 0.56 (0.30-1.04) for independent review committee (IRC)-assessed cORR and 0.98 (0.53-1.82) for investigator (INV)-assessed cORR. The weighted hazard ratio (HR) comparing mobocertinib to amivantamab was 0.74 (0.51-1.07) for IRC-assessed PFS, 0.92 (0.57-1.48) for OS, and 0.59 (0.30-1.18) for INV-assessed DoR. CONCLUSION: MAIC analysis showed that mobocertinib and amivantamab had similar efficacy in patients with NSCLC harboring EGFR ex20ins mutations whose disease progressed during or after platinum-based chemotherapy. These findings may benefit patients by supporting future treatment options.

Long-term survival after stereotactic body radiotherapy combined with immunotherapy plus anti-angiogenesis therapy in patients with advanced non-small cell lung cancer and EGFR exon 20 insertion mutation: a report of two cases.

Background: Epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutation is the third most common EGFR-mutant form, accounting for 10-12% of all EGFR mutations in non-small cell lung cancer (NSCLC). Chemotherapy was the first-line treatment for patients with EGFR ex20ins mutation in the era when EGFR ex20ins tyrosine kinase inhibitors (EGFR ex20ins-TKIs) were inaccessible. Although EGFR ex20ins-TKIs have since then demonstrated certain efficacy, the population benefit rate is not high due to the high cost of the drug and limited benefit to the population. Therefore, the choice of treatment modality when a patient does not have access to EGFR ex20ins-TKIs or are resistant to them remains an avenue worth exploring. Case Description: In this report, we present two cases of patients with lung adenocarcinoma and EGFR ex20ins mutation. The two patients were middle-aged Asian women with no smoking history, and both had one or more metastatic lesions. Both achieved long-term clinical benefit (progression-free survival ≥12 months) after receiving combined treatment, suggesting that this is a promising treatment modality. Conclusions: To the best of our knowledge, this is the first report supporting the combination of stereotactic body radiotherapy and apatinib and camrelizumab as an effective treatment strategy in patients with advanced EGFR ex20ins-positive NSCLC who have been previously treated with chemotherapy. The therapy described in this report might serve as a potential alternative approach for clinical oncologists.

An insertion mutation of the MECP2 gene in severe neonatal encephalopathy and ocular and oropharyngeal dyskinesia: a case report.

BACKGROUND: Pathogenic variation of the MECP2 gene presents mostly as Rett syndrome in females and is extremely rare in males. Most male patients with MECP2 gene mutation show MECP2 duplication syndrome. CASE PRESENTATION: Here we report a rare case in a 10-month-old boy with a hemizygous insertion mutation in MECP2 as NM_001110792, c.799_c.800insAGGAAGC, which results in a frameshift mutation (p.R267fs*6). The patient presented with severe encephalopathy in the neonatal period, accompanied by severe development backwardness, hypotonia, and ocular and oropharyngeal dyskinesia. This is the first report of this mutation, which highlights the phenotype variability associated with MECP2 variants. CONCLUSIONS: This case helps to expand the clinical spectrum associated with MECP2 variants. Close attention should be paid to the growth and development of patients carrying a MECP2 variant or Xq28 duplication. Early interventions may help improve symptoms to some certain extent.

Rapid Detection of SARS-CoV-2 RNA Using Reverse Transcription Recombinase Polymerase Amplification (RT-RPA) with Lateral Flow for N-Protein Gene and Variant-Specific Deletion-Insertion Mutation in S-Protein Gene.

Rapid molecular testing for severe acute respiratory coronavirus 2 (SARS-CoV-2) variants may contribute to the development of public health measures, particularly in resource-limited areas. Reverse transcription recombinase polymerase amplification using a lateral flow assay (RT-RPA-LF) allows rapid RNA detection without thermal cyclers. In this study, we developed two assays to detect SARS-CoV-2 nucleocapsid (N) gene and Omicron BA.1 spike (S) gene-specific deletion-insertion mutations (del211/ins214). Both tests had a detection limit of 10 copies/µL in vitro and the detection time was approximately 35 min from incubation to detection. The sensitivities of SARS-CoV-2 (N) RT-RPA-LF by viral load categories were 100% for clinical samples with high (>9015.7 copies/µL, cycle quantification (Cq): < 25) and moderate (385.5-9015.7 copies/µL, Cq: 25-29.9) viral load, 83.3% for low (16.5-385.5 copies/µL, Cq: 30-34.9), and 14.3% for very low (<16.5 copies/µL, Cq: 35-40). The sensitivities of the Omicron BA.1 (S) RT-RPA-LF were 94.9%, 78%, 23.8%, and 0%, respectively, and the specificity against non-BA.1 SARS-CoV-2-positive samples was 96%. The assays seemed more sensitive than rapid antigen detection in moderate viral load samples. Although implementation in resource-limited settings requires additional improvements, deletion-insertion mutations were successfully detected by the RT-RPA-LF technique.

Possible False Results With cobas® EGFR Mutation Test v2 and Oncomine Dx Target Test for EGFR Mutation.

BACKGROUND/AIM: Disparities in the results of next-generation sequencing-based multiplex gene panel tests and those of single-gene tests when detecting epidermal growth factor receptor (EGFR) mutations in non-small-cell lung cancer (NSCLC) have been reported. However, the possible underlying causes have not been investigated. The aim of this study was to explore the possibilities and causes of false results obtained using cobas® EGFR Mutation Test v2 (cobas® EGFR) and Oncomine Dx Target Test (ODxTT). PATIENTS AND METHODS: The data of patients with NSCLC who underwent gene assessment using both cobas® EGFR and ODxTT between April 2021 and May 2022 were retrospectively reviewed. Disparate results of EGFR mutation analyses were then reviewed. RESULTS: One hundred and sixteen patients were included in the analysis. The results of six samples were inconsistent. In four samples, exon 20 insertion mutations were detected using cobas® EGFR, but not identified using ODxTT. A fragment analysis was performed on three of the four samples, and all showed negative results for exon 20 insertion. Furthermore, one false negative result was obtained in the ODxTT for both exon 19 deletion and L858R mutations. For exon 19 deletion mutation, a single nucleotide variant from adenine to thymine was identified close to the mutation site. CONCLUSION: False positives for exon 20 insertion may occur when using cobas® EGFR, and false negatives for exon 19 deletion and L858R mutations may occur when using ODxTT.

HER2 exon 20 insertion mutations and myelosuppression in lung adenocarcinoma patient: a case report and response to trastuzumab deruxtecan.

BACKGROUND: Human epidermal growth factor receptor 2 (HER2) mutations occur in 2% of lung cancers. CASE PRESENTATION: In this report, we presented a case of an Asian female who was diagnosed with lung adenocarcinoma. NGS results indicated HER2 exon 20 insertion mutation and PET/CT results showed multiple metastases in lower lobes of both lungs. Thereafter, she was treated with chemotherapy alone, combination of chemotherapy and targeted therapy and immunotherapy. Due to progressive disease, she was then received DS-8201. Imaging data indicated partial response to DS-8201 and tumor marker values decreased significantly, suggesting good efficacy. Nevertheless, DS-8201 was discontinued because of the development of myelosuppression (grade 3). Finally, she died at home due to platelet deficiency, white blood cell (grade 4), granulocytopenia, intracranial hemorrhage and gastrointestinal hemorrhage. CONCLUSIONS: This was an important case since it exerted effective response to DS-8201. Meanwhile, myelosuppression is also found in the patient, which requires attention to pulmonary symptoms and careful monitoring.

Distribution and Detectability of EGFR Exon 20 Insertion Variants in NSCLC.

INTRODUCTION: EGFR exon 20 insertion (ex20ins) mutations represent 5% to 10% of EGFR mutations in NSCLC. Identifying patients with EGFR ex20ins is challenging owing to the limited coverage of polymerase chain reaction (PCR) assays and the relatively recent use of next-generation sequencing (NGS). This study analyzes the spectrum of EGFR ex20ins variants in a large patient population from a global clinical trial and several real-world cohorts and the ability of PCR kits to identify these alterations. METHODS: We conducted this retrospective analysis in patients with NSCLC who underwent NGS or other sequencing testing and had a known EGFR ex20ins mutation. Patients were gathered from a clinical trial (NCT02716116), a chart review study in Germany, and the LC-SCRUM-Japan, GENIE, and U.S. COTA databases. Proportions of patients with ex20ins variants that could have been detected by six commercially available and widely used PCR kits were calculated in each data set. RESULTS: Overall, 636 patients with NSCLC harboring EGFR ex20ins mutations were included in this analysis and 104 unique EGFR ex20ins variants were identified across the data sources. The proportion of patients whose ex20ins could have been detected by any PCR test alone ranged from 11.8% to 58.9% across the data sources. CONCLUSIONS: Our findings suggest that the PCR tests evaluated would have missed more than 40% of patients with NSCLC harboring EGFR ex20ins mutations. NGS-based genetic testing is preferable than standard PCR assays and can substantially improve the identification of the diverse profile of EGFR ex20ins variants in NSCLC.

Real-world efficacy and safety of mobocertinib in EGFR exon 20 insertion-mutated lung cancer.

Background: Non-small cell lung cancer (NSCLC) harboring EGFR exon 20 insertions (EGFRex20ins) is relatively resistant to the existing EGFR tyrosine kinase inhibitors (TKIs). Mobocertinib is a novel TKI that selectively targets EGFRex20ins and has demonstrated therapeutic efficacy in pretreated patients with tumors harboring these mutations. Methods: This is a retrospective, non-interventional, multicenter real-world study aimed at assessing the efficacy and safety of mobocertinib in patients with EGFRexon20ins who received 160 mg QD monotherapy as part of expanded access. Data collection was based on patients' records. PET-CT or CT scans were used to measure systemic response, while brain MRIs were used to examine intracranial response as part of the follow-up. Results: 16 patients were included in this report. Mobocertinib was administered to 31.3% (5) of patients as first-line, 50% (8) as second-line, and 18.7% (3) as a later-line therapy. The median age was 65 years (range, 38-83), 75% (12/16) were female, and 50% (8/16) had brain metastases at baseline before mobocertinib treatment. The objective response rate (ORR) to mobocertinib was 25% (4/16) (1/5 for first line and 3/11 for other lines), disease control rate (DCR) was 75% (12/16) with a follow-up period of 11 months. The median duration of treatment (mDoT) was 5.6 months across all patients, and 8.6 months in responders. Based on the presence or absence of brain metastasis, the mDoT was 14.8 and 5.4 months (p=0.01), respectively. Mobocertinib Grade ≥3 treatment-related adverse events (TRAEs) included diarrhea (19%), nausea (6%) and renal failure (6%). Dose reduction was reported in 25% of cases to 80 mg. Conclusion: Mobocertinib in compassionate use exhibited an ORR of 25%, which is very similar to that of the phase 2 EXCLAIM study and clearly better than historical data of monochemotherapy or conventional EGFR inhibitors. The greatest benefit was noted in patients without brain metastases, who showed durable effects with mDoT 14.8 months, while intracranial activity was limited. These findings may assist therapeutic considerations, inasmuch as results from the EXCLAIM cohort-3 dedicated to brain lesions are not available yet.

Case Report: A good response to furmonertinib second-line treatment of an advanced lung adenocarcinoma patient with a rare EGFR exon 20 N771_P772insH mutation: A case report and literature review.

Background: Lung adenocarcinoma with the classical EGFR 19 deletion and exon 21 L858R point mutations has exhibited good responses to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treatment. However, the sensitivity of uncommon EGFR exon 20 insertion mutation to third-generation EGFR-TKIs has not been determined. Although emerging targeted therapies for EGFR exon 20 insertion mutation have been reported in recent years, such patients still have a poorer prognosis than those with typical or wild-type EGFR mutations. Case summary: Here, we report the case of a 57-year-old man with advanced non-small cell lung cancer (NSCLC) with a rare EGFR exon 20 N771_P772insH mutation. The patient was treated with furmonertinib as second-line therapy. Although his pleural effusion was more than before that during treatment, various examination results showed that the pleural effusion was closely related to hypoproteinemia; thus, local progression was not considered. His cough was significantly alleviated, and the dose was well tolerated. The patient was evaluated for a remarkable progression-free survival (PFS) of 10.0 months, a duration of response (DOR) of 8.0 months, and an overall survival (OS) of 22.0 months, which had not previously been achieved. Conclusion: The present study indicated that furmonertinib might be a good treatment option for first-line progressive NSCLC patients with EGFR exon 20 insertion mutation.

The identification of a novel frameshift insertion mutation in the EXT1 gene in a Chinese family with hereditary multiple exostoses.

To identify the pathogenic gene variation in a Chinese family with Hereditary Multiple Exostoses (HME). By examining blood-sourced DNA and clinical manifestations of the proband and his family members, the whole exome sequencing (WES) and Sanger sequencing were used to detect possibly pathogenic mutations. A novel heterozygous mutation (c.325dup) was identified in exon 1 of the exostosin 1 (EXT1) gene from the proband and the affected family members. And we found this mutation was absent in all the unaffected family members. This c.325dup mutation is in the exon 1 domain of the EXT1 gene and the change of p.C109Lfs*80 cause the early termination of protein translation. The identification of the novel frameshift insertion mutation (c.325dup) expands the mutation spectrum of HME, which provides new evidence for HME diagnosis.

An insertion mutation in the Apoe gene associated with spontaneous hyperlipidemia in mice.

Introduction: Spontaneously hyperlipidemic (SHL) mice, a mouse strain derived from an inbred strain of Japanese wild (original)-type mice (KOR; Mus musculus molossinus), show high plasma cholesterol concentrations with disruption of the apolipoprotein E (Apoe) gene. However, the details of the Apoe gene of SHL mice have yet to be described. Material and methods: The DNA sequence of the Apoe gene of SHL mice was compared to that of control KOR mice in genomic DNA and cDNA analyses. Results: In the DNA analysis, a 4700-bp fragment was found to be inserted into exon 4 of the Apoe gene of SHL mice. The insertion contained two 365-bp repeats at each terminal and was flanked by a 6-bp target duplication at each side. The inserted fragment produced a frameshift of an early stop codon, resulting in a protein product that consisted of 87 amino acids in SHL mice compared to 311 amino acids in control KOR mice. Conclusions: These findings provide useful information about the molecular basis of SHL mice and related lipid disorders.

Case Report: Exceptional Response to Poziotinib in Patient with Metastatic Non-Small Cell Lung Cancer With EGFR Exon 20 Insertion Mutation.

Among the several next-generation tyrosine kinase inhibitors (TKIs) tested against uncommon EFGR alterations, poziotinib has been demonstrated to be a powerful agent for metastatic non-small-cell lung cancer (mNSCLC) with aberrations in HER2 exon 20, and FDA approval is being sought in the previously-treated population. Poziotinib has also shown activity in mNSCLC with aberrations in EGFR exon 20. Herein, we report the first published case of a patient affected by mNSCLC harbouring an EGFR exon 20 insertion (EGFRex20ins) mutation who achieved a complete response (CR) under treatment with poziotinib as part of the ZENITH20 trial. In January 2021, a former smoker 62-year-old female patient was diagnosed with relapse, after two surgeries and post-operative chemotherapy of mNSCLC, at liver and retroperitoneal nodes. Given the identification by Next Generation Sequencing (NGS) of EGFRex20ins mutation, she was enrolled in ZENITH20-cohort 5 trial, a phase 2 multicentre study aimed to assess the efficacy and safety of poziotinib in patients with EGFR or HER2 exon 20 insertion mutations. Poziotinib as first-line systemic therapy for metastatic disease was initiated at the end of January 2021 and administrated at the initial dosage of 8 mg orally twice daily (BID). The most common side effects from the beginning of the treatment included alopecia, macular skin rash, diarrhoea, xerostomia, and conjunctivitis. Due to these adverse events, poziotinib was discontinued during the first 3 months and then reduced to 6 mg orally BID in April 2021. After the dose de-escalation, the adverse events ameliorated, and the patient better tolerated the treatment without further interruption. Since the first reevaluation (after 4 weeks of therapy), the treatment with poziotinib resulted to be remarkably effective, with a partial response (PR) subsequently confirmed in May and July 2021. Then, in October 2021, a CT scan confirmed a CR, maintained with good tolerance at the last reevaluation in February 2022. Treatment is still ongoing at the same dosage. In this case, poziotinib has represented a successful and well-tolerated first-line treatment alternative to chemotherapy in this patient with EGFR exon 20 insertion mutated mNSCLC.