Predictive and Prognostic Potential of TP53 in Patients With Advanced Non-Small-Cell Lung Cancer Treated With EGFR-TKI: Analysis of a Phase III Randomized Clinical Trial (CTONG 0901)

Outcomes in non-small cell lung cancer with uncommon epidermal growth factor receptor L858 substitutions under first-line epidermal growth factor receptor tyrosine kinase inhibitors: A large real-world cohort study

Atypical L858R or other L858X mutations in the epidermal growth factor receptor (EGFR) gene, beyond the classical EGFRL858R mutation caused by c.2573 T > G, have been identified in non-small cell lung cancer (NSCLC), yet their genomic features and survival benefits with EGFR tyrosine kinase inhibitor (TKI) treatment have not been fully explored. We retrospectively enrolled 489 NSCLC patients with baseline tumor tissue/plasma samples carrying uncommon EGFRL858R (N = 124), EGFRL858Q/M (N = 17), or classical EGFRL858R mutations (N = 348). The comparison of molecular features was performed using treatment-naïve tumor tissues. Survival benefits and resistance mechanisms of first-line EGFR TKI treatment were studied in an advanced disease subcohort. NSCLCs harboring uncommon EGFRL858R had lower TP53 mutation prevalence (p = 0.04) and chromosome instability scores (p = 0.02) than those with classical EGFRL858R. Concomitant EGFRL861Q mutations were enriched in NSCLCs with EGFRL858Q/M (p < 0.01), with cooccurrence in those carrying EGFRL858M. Patients with uncommon EGFRL858R experienced improved progression-free survival (PFS) compared to those with classical EGFRL858R (median: 13.0 vs. 10.0 months, hazard ratio [HR]: 0.57, 95% confidence interval [CI]: 0.41-0.80). The association remained significant when adjusting for sex, age, histological subtype, TKI category, and anti-vascular therapy (HR: 0.55, 95% CI: 0.39-0.77). Furthermore, EGFRL858Q/M patients showed enhanced first-line PFS (vs. classical EGFRL858R, HR: 0.26, 95% CI: 0.10-0.67), potentially benefiting more from afatinib. Additionally, NSCLCs with uncommon EGFRL858R and classical EGFRL858R had similar resistance profiles to EGFR TKIs. In conclusion, NSCLCs carrying atypical EGFR L858 aberrations, which had fewer TP53 mutations and higher chromosome stability, exhibited improved PFS under first-line EGFR TKIs than those with the classical EGFRL858R.

Amivantamab plus lazertinib versus osimertinib in first-line EGFR-mutant advanced non-small-cell lung cancer with biomarkers of high-risk disease: a secondary analysis from MARIPOSA

BACKGROUND

Amivantamab-lazertinib significantly prolonged progression-free survival (PFS) versus osimertinib in patients with epidermal growth factor receptor (EGFR)-mutant advanced non-small-cell lung cancer [NSCLC; hazard ratio (HR) 0.70; P < 0.001], including those with a history of brain metastases (HR 0.69). Patients with TP53 co-mutations, detectable circulating tumor DNA (ctDNA), baseline liver metastases, and those without ctDNA clearance on treatment have poor prognoses. We evaluated outcomes in these high-risk subgroups.

PATIENTS AND METHODS

This analysis included patients with treatment-naive, EGFR-mutant advanced NSCLC randomized to amivantamab-lazertinib (n = 429) or osimertinib (n = 429) in MARIPOSA. Pathogenic alterations were identified by next-generation sequencing (NGS) of baseline blood ctDNA with Guardant360 CDx. Ex19del and L858R ctDNA in blood was analyzed at baseline and cycle 3 day 1 (C3D1) with Biodesix droplet digital polymerase chain reaction (ddPCR).

RESULTS

Baseline ctDNA for NGS of pathogenic alterations was available for 636 patients (amivantamab-lazertinib, n = 320; osimertinib, n = 316). Amivantamab-lazertinib improved median PFS (mPFS) versus osimertinib for patients with TP53 co-mutations {18.2 versus 12.9 months; HR 0.65 [95% confidence interval (CI) 0.48-0.87]; P = 0.003} and for patients with wild-type TP53 [22.1 versus 19.9 months; HR 0.75 (95% CI 0.52-1.07)]. In patients with EGFR-mutant, ddPCR-detectable baseline ctDNA, amivantamab-lazertinib significantly prolonged mPFS versus osimertinib [20.3 versus 14.8 months; HR 0.68 (95% CI 0.53-0.86); P = 0.002]. Amivantamab-lazertinib significantly improved mPFS versus osimertinib in patients without ctDNA clearance at C3D1 [16.5 versus 9.1 months; HR 0.49 (95% CI 0.27-0.87); P = 0.015] and with clearance [24.0 versus 16.5 months; HR 0.64 (95% CI 0.48-0.87); P = 0.004]. Amivantamab-lazertinib significantly prolonged mPFS versus osimertinib among randomized patients with [18.2 versus 11.0 months; HR 0.58 (95% CI 0.37-0.91); P = 0.017] and without baseline liver metastases [24.0 versus 18.3 months; HR 0.74 (95% CI 0.60-0.91); P = 0.004].

CONCLUSIONS

Amivantamab-lazertinib effectively overcomes the effect of high-risk features and represents a promising new standard of care for patients with EGFR-mutant advanced NSCLC.

The prognosis of TP53 and EGFR co-mutation in patients with advanced lung adenocarcinoma and intracranial metastasis treated with EGFR-TKIs

Background

TP53 mutation is a poor factor for non-small cell lung cancer (NSCLC), while the effect of TP53 on prognosis in epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma (LUAD) with brain metastasis remains elusive and needs further exploration.

Methods

We retrospectively analyzed 236 patients and tested for TP53- and EGFR-mutant status in metastasis LUAD patients who had received first-line EGFR-tyrosine kinase inhibitor (TKI) treatment. Survival rates were calculated by the Kaplan-Meier method. Furthermore, univariate and multivariate Cox analyses were performed to identify the independent prognostic factors.

Results

There were 114 patients with confirmed non-brain metastasis (NBM), 74 patients with preliminary diagnosis early brain metastasis (EBM), and 48 patients with late brain metastasis (LBM). TP53 and EGFR co-mutations were found in 35/236 patients (14.8%). The median progression-free survival (PFS) and overall survival (OS) in the EGFR mutation and TP53 wild-type group were significantly longer than those in the EGFR and TP53 co-mutation group in all advanced LUAD or NBM. Concurrently, PFS and OS were found to be not significant in EBM and LBM patients. Subgroup analysis revealed longer median PFS and OS in the TP53 wild-type group compared to the TP53 mutant group in L858R patients and not significant in EGFR Exon 19 deletion patients. In LBM patients, the time to brain metastasis in the EGFR mutation and TP53 wild-type group was longer than that in the EGFR and TP53 co-mutation group, and TP53 mutant status was an independent prognostic factor for brain metastasis. The TP53 wild-type group exhibited a higher objective remission rate (ORR) and disease control rate (DCR) than the TP53 mutant group in NBM, EBM, and LBM patients, irrespective of primary lung and brain metastatic lesions.

Conclusion

TP53/EGFR co-mutation patients receiving first-line EGFR-TKI treatment had poor prognoses in advanced LUAD, especially with L858R mutation. Moreover, TP53/EGFR co-mutation patients treated with EGFR-TKIs may more easy developed intracranial metastasis.

Valproic acid increased the efficacy of EGFR TKIs on EGFR/TP53 co-mutated lung cancers and downregulated mutant-p53 levels

The TP53 tumor suppressor is the most frequently mutated gene in human cancers. For p53-targeted therapy, one of the strategies was targeting mutant p53 for degradation. In EGFR-mutated lung cancer patients, concurrent TP53 mutation was associated with faster resistance to EGFR-TKIs. In this study, we discovered that valproic acid (VPA), a widely prescribed antiseizure medication, had a synergic effect on sensitive as well as acquired resistant lung cancers with EGFR/TP53 co-mutation in combination with EGFR-TKIs. In both in vitro and in vivo models, VPA greatly improved the efficacy of EGFR-TKIs, including forestalling the occurrence of acquired resistance and increasing the sensitivity to EGFR-TKIs. Mechanistically, VPA dramatically promoted degradation of mutant p53 in both sensitive and acquired resistant cells while inhibited mutant TP53 mRNA transcription only in sensitive cells. Together, this study suggested that VPA combination treatment could have beneficial effects on EGFR-mutant lung cancers with concurrent p53 mutation in both early and late stages, expanding the potential clinical applications for VPA.

Clinical significance of TP53 alterations in advanced NSCLC patients treated with EGFR, ALK and ROS1 tyrosine kinase inhibitors: An update

 The development of targeted therapies for non-small cell lung cancer (NSCLC), such as the epidermal growth factor receptor (EGFR), anaplastic lymphoma receptor tyrosine kinase (ALK), and ROS proto-oncogene 1 (ROS1), has improved patients' prognosis and significantly extended progression-free survival. However, it remains unclear why some patients do not benefit from the treatment as much or have a rapid disease progression. It is considered that, apart from the oncogenic driver gene, molecular alterations in a number of caretaker and gatekeeper genes significantly impact the efficacy of targeted therapies. The tumor protein 53 (TP53) gene is one of the most frequently mutated genes in NSCLC. To date, numerous studies have investigated the influence of various TP53 alterations on patient prognosis and responsiveness to therapies targeting EGFR, ALK, or ROS1. This review focuses on the latest data concerning the role of TP53 alterations as prognostic and/or predictive biomarkers for EGFR, ALK, and ROS1 tyrosine kinase inhibitors (TKIs) in advanced NSCLC patients. Since the presence of TP53 mutations in NSCLC has been linked to its decreased responsiveness to EGFR, ALK, and ROS1 targeted therapy in most of the referenced studies, the review also discusses the impact of TP53 mutations on treatment resistance. It seems plausible that assessing the TP53 mutation status could aid in patient stratification for optimal clinical decision-making. However, drawing meaningful conclusions about the clinical value of the TP53 co-mutations in EGFR-, ALK- or ROS1-positive NSCLC is hampered mainly by an insufficient knowledge regarding the functional consequences of the TP53 alterations. The integration of next-generation sequencing into the routine molecular diagnostics of cancer patients will facilitate the detection and identification of targetable genetic alterations along with co-occurring TP53 variants. This advancement holds the potential to accelerate understanding of the biological and clinical role of p53 in targeted therapies for NSCLC.

Lung adenocarcinomas with isolated TP53 mutation: A comprehensive clinical, cytopathologic and molecular characterization

BACKGROUND

TP53 mutation is present in about 50.8% of lung adenocarcinomas, frequently in combination with other genetic alterations. However, a rare subset harbors the TP53 mutation alone.

METHODS

Next-generation sequencing was performed in 844 lung adenocarcinomas diagnosed by fine needle aspiration. Fourteen cases (1.7%) showed isolated TP53 alteration and were subjected to a comprehensive analysis.

RESULTS

The average age at diagnosis was 65.7 years (range 48-79); 9 males and 5 females. All were smokers with an average pack-year of 40.7 (range 10-70). Ten had metastases, mostly in the brain (n = 4) and pleura (n = 4). After a follow-up period of up to 102 months, 9 died, 3 were alive free of disease, 1 was alive with disease, and 1 was lost to follow-up. The median survival was 12.2 months. Most tumors exhibited poor differentiation, composed of solid sheets with moderate to severe atypia, increased mitotic activity, and necrotic background. Half were positive for TTF-1 and showed p53 overexpression. PD-L1 was positive in 5 cases. Most alterations were missense mutations in exons 5-8, and this mutation type was associated with p53 overexpression. Tumors with combined missense mutation and truncated protein had higher PD-L1 expression along with a trend towards an increase in tumor mutational burden (TMB). CEBPA deletion of undetermined significance was the most common copy number alteration.

CONCLUSION

Isolated TP53 mutation was seen in association with smoking, high-grade cytomorphologic features, adverse prognosis, and recurrent CEBPA deletions. These tumors tend to have strong PD-L1 expression and high TMB, suggesting potential benefit from immune checkpoint inhibitors. Hence, the recognition of this molecular group has prognostic and therapeutic implications.

Prognostic Significance of Tumor Mutation Burden among Patients with Non-small Cell Lung Cancer Who Received Platinum-based Adjuvant Chemotherapy: An Exploratory Study

This study aimed to investigate the prognostic significance of tumor mutation burden (TMB) among patients with non-small cell lung cancer (NSCLC) who received platinum-based adjuvant chemotherapy. Tumor tissue specimens after surgical resection were collected for DNA extraction. Somatic mutation detection and TMB analysis were conducted using next-generation sequencing (NGS). Recurrence status of the patients was assessed in the hospital during the adjuvant chemotherapy period, and long-term survival data of patients were obtained by telephone follow-up. Univariate analysis between TMB status and prognosis was carried out by survival analysis. A retrospective review of 78 patients with non-squamous NSCLC who received platinum-based adjuvant chemotherapy showed a median disease-free survival of 3.6 years and median overall survival (OS) of 5.3 years. NGS analysis exhibited that the most common mutated somatic genes among the 78 patients were tumor suppressor protein p53 (TP53), epidermal growth factor receptor, low-density lipoprotein receptor related protein 1B, DNA methyltransferase 3 alpha and FAT atypical cadherin 3, and their prevalence was 56.4%, 48.7%, 37.2%, 30.7%, and 25.6%, respectively. TMB status was divided into TMB-L (≤ 4.5/Mb) and TMB-H (> 4.5/Mb) based on the median TMB threshold. Relevance of TMB to prognosis suggested that the median OS of patients with TMB-L was significantly longer than that of patients with TMB-H (NR vs. 4.6, P = 0.014). Higher TMB status conferred a worse implication on OS among patients with non-squamous NSCLC who received platinum-based adjuvant chemotherapy.

The impact of genomic context on outcomes of solid cancer patients treated with genotype-matched targeted therapies: a comprehensive review

INTRODUCTION

A critical need in the field of genotype-matched targeted therapy in cancer is to identify patients unlikely to respond to precision medicines. This will manage expectations of individualised therapies and avoid clinical progression to a point where institution of alternative treatments might not be possible. We examined the evidence base of the impact of genomic context on which targeted alterations are inscribed to identify baseline biomarkers distinguishing those obtaining the expected response from those with less benefit from targeted therapies.

METHODS

A comprehensive narrative review was conducted: scoping searches were undertaken in PubMed, Cochrane Database of Systematic Reviews, and PROSPERO. Outcomes included in meta-analysis were progression-free and overall survival. Data were extracted from Kaplan-Meier and used to calculate hazard ratios. Studies presenting data on two molecular subcohorts (e.g. co-mutation versus no co-mutation) were included in fixed meta-analysis. Other studies were used for descriptive purposes.

RESULTS

The presence of concomitant driver mutations, higher tumour mutational burden (TMB), greater copy number burden, and APOBEC signatures significantly reduces benefits of targeted therapy in lung cancers in never smokers (LCINS - less than 100 cigarettes per lifetime) and breast cancer, cancers with low TMB. LCINS have significantly poorer outcomes if their cancers harbour p53 co-mutations, an effect also seen in human epidermal growth factor receptor 2-positive (HER2+) breast cancer patients (trastuzumab) and head and neck cancer patients [phosphoinositide 3-kinase (PI3K) inhibition]. PI3K co-alterations have less impact when targeting epidermal growth factor receptor mutations and anaplastic lymphoma kinase fusions, but significantly reduce the impact of targeting HER2 and MET amplifications. SMARCA4 co-mutations predict for poor outcome in patients treated with osimertinib and sotorasib. In BRAF-mutant melanoma, whilst there are no genomic features distinguishing exceptional responders from primary progressors, there are clear transcriptomic features dichotomising these outcomes.

CONCLUSION

To our knowledge, this is the most comprehensive review to date of the impact of genomic context on outcomes with targeted therapy. It represents a valuable resource informing progress towards contextualised precision medicine.

Combination of genomic instability score and TP53 status for prognosis prediction in lung adenocarcinoma

The genomic instability (GI) /homologous recombination deficiency (HRD) score, calculated as the sum of the events of loss of heterozygosity (LOH), large-scale state transition (LST) and telomere allele imbalance (TAI), is used to guide the choice of treatment in several cancers, but its relationship with genomic features, clinicopathological characteristics and prognosis in lung cancer is poorly understood, which could lead to population bias in prospective studies. We retrospectively analyzed 1011 lung cancer patients whose tumor samples were successfully profiled by high-throughput sequencing panel including GI/HRD score. Alterations of many cancer suppressor genes were associated with higher GI/HRD scores, biallelic inactivation of TP53 was correlated with a high GI/HRD score. A combination of two gene alterations exhibited a higher GI/HRD scores than single gene alterations. The GI/HRD score was associated with advanced stages in lung adenocarcinoma but not in lung squamous cell carcinoma. Furthermore, patients with higher GI/HRD scores had significantly shorter overall survival and progression-free survival than patients with lower GI/HRD scores. Finally, patients with a combination of a higher GI/HRD scores and TP53 alteration exhibited an extremely poor prognosis compared with patients with a lower GI/HRD scores and wild-type TP53 (overall survival, training cohort, hazard ratio (HR) = 8.56, P < 0.001; validation cohort, HR = 6.47, P < 0.001; progression-free survival, HR = 4.76, P < 0.001). Our study revealed the prognostic value of the GI/HRD score in lung adenocarcinoma, but not for all lung cancer. Moreover, the combination of the GI/HRD score and TP53 status could be a promising strategy to predict the prognosis of patients with lung adenocarcinoma.

Correlation Analysis of the TP53 Mutation With Clinical Characteristics in the Prognosis of Non-Small Cell Lung Cancer

Background

Non-small cell lung cancer (NSCLC) with TP53 mutations has a worse prognosis. It was generally more resistant to chemotherapy and radiation. Our aim was to investigate the correlation between the TP53 co-mutated gene and clinical features, and prognostic value in patients with NSCLC.

Methods

Seventy-three patients with a diagnosis of NSCLC at our hospital were recruited. They were divided into the TP53 mutation status (minor) (TP53 MU) and TP53 wild-type (major) (TP53 WT) groups according to their clinical characteristics after their mutation data and clinical information were collected. Serum markers were compared between groups using Mann-Whitney U test. Other clinical factors were compared between groups using χ2 test and Fisher exact test. The log-rank test was used to compare survival curves.

Results

Of the 73 patients with NSCLC, 37 (50.68%) were found to carry TP53 mutation. TP53 MU and TP53 WT groups (n = 36) showed a significant difference in the number of smokers, incidence of squamous cell carcinoma, EGFR mutation, and number of advanced patients (P < .05), while gender, age, lymph node metastasis, and KRAS mutation did not differ significantly between the 2 groups. The survival curves in the TP53/KRAS and the TP53/EGFR co-mutation groups suggest that patients with NSCLC may have a shorter progression-free survival (PFS) if they carry one of the 2 types of co-mutation.

Conclusions

TP53 gene mutations are more common in patients with NSCLC and squamous cell carcinoma. New predictive markers for NSCLC prognosis may be TP53/KRAS and TP53/EGFR co-mutations.

Concordance of Abundance for Mutational EGFR and Co-Mutational TP53 with Efficacy of EGFR-TKI Treatment in Metastatic Patients with Non-Small-Cell Lung Cancer

The present study aimed to investigate the influence of the mutation abundance of the epidermal growth factor receptor (EGFR) and its co-mutation with TP53 on the therapeutic efficacy of tyrosine kinase inhibitor (TKI) treatment in patients with metastatic lung adenocarcinoma (LUAD). In total, 130 patients (January 2018-September 2022) with metastatic LUAD from the Second Affiliated Hospital of Zhejiang University were included. Kaplan-Meier analysis was performed to measure the duration of drug application (DDA) and the log-rank test was used to compare differences. Univariate and multivariate analyses of Cox proportional hazard regression models were used to evaluate the association between the relevant clinicopathological factors and DDA. Hazard ratios with 95% confidence intervals were also calculated. Among the 130 patients who were treated with first-generation EGFR-TKIs, 86 showed high-EGFR mutation abundance (>22.0%) and 44 showed low-EGFR mutation abundance (≤22.0%). Patients in the high-EGFR group had a greater DDA than those in the low-EGFR group (p < 0.05). The results of the subgroup analysis were consistent with those of the total mutation population (exon19: >18.5% vs. ≤18.5%, 14 months vs. 10 months, p = 0.049; exon21: >22.0% vs. ≤22.0%, 15 months vs. 9 months, p = 0.005). In addition, the mutation abundance of TP53 was negatively correlated with the DDA (p < 0.05). Patients in the combination group had a better DDA than those in the monotherapy group (p < 0.05). Subgroup analysis showed that, among the low mutation abundance of the EGFR exon 21 or 19 cohort, the combination group had a better DDA than the monotherapy group (p < 0.05). An EGFR mutation abundance greater than 22.0% was a positive predictor of DDA in patients with metastatic LUAD. However, a TP53 mutation abundance higher than 32.5% could reverse this situation. Finally, first-line treatment with EGFR-TKIs plus chemotherapy is a potential treatment strategy for patients with low-abundance EGFR mutations.

The significance of co-mutations in EGFR-mutated non-small cell lung cancer: Optimizing the efficacy of targeted therapies?

Non-small cell lung cancer (NSCLC) is the most common cause of cancer death worldwide. In non-squamous NSCLC, the identification of oncogenic drivers and the development of target-specific molecules led to remarkable progress in therapeutic strategies and overall survival over the last decade. Nevertheless, responses are limited by systematically acquired mechanisms of resistance early on after starting a targeted therapy. Moreover, mounting evidence has demonstrated that each oncogenic-driven cluster is actually heterogeneous in terms of molecular features, clinical behaviour, and sensitivity to targeted therapy. In this review, we aimed to examine the prognostic and predictive significance of oncogene-driven co-mutations, focusing mainly on EGFR and TP53. A narrative review was performed by searching MEDLINE databases for English articles published over the last decade (from January 2012 until November 2022). The bibliographies of key references were manually reviewed to select those eligible for the topic. The genetic landscape of EGFR-mutated NSCLC is more complicated than what is known so far. In particular, the occurrence of TP53 co-mutations stratify patients carrying EGFR mutations in terms of treatment response. The study provides a deeper understanding of the mechanisms underlying the variability of the genetic landscape of EGFR-mutated NSCLC and summarizes notably the clinical importance of TP53 co-mutations for an open avenue to more properly addressing the clinical decision-making in the near future.

Genomic landscape and efficacy of HER2-targeted therapy in patients with HER2-mutant non-small cell lung cancer

Background

HER2-targeted therapy provides survival benefits to HER2-mutant non-small cell lung cancer (NSCLC). A better understanding of the clinical and genomic characterization of treatment-naïve HER2-positive NSCLC, as well as the efficacy of and resistance to HER2-targeted therapy in HER2-altered NSCLC, could promote further improvement of HER2 targeted therapy.

Methods

HER2-altered NSCLC patients was retrospectively included and their genomic profiles were performed by next-generation sequencing. The clinical outcomes included overall response rate, disease control rate and progression-free survival.

Results

Among 176 treatment-naïve patients with HER2 alterations, 64.8% harbored HER2 mutations with/without HER2 amplification, and 35.2% carried HER2 amplification only. Molecular characterization was correlated with tumor stage that late-stage NSCLC with HER2 oncogenic mutations showed a higher prevalence of TP53 mutations and a higher tumor mutation burden. However, this correlation was not found in patients with HER2 amplification only. Twenty-one patients with HER2 alterations treated with pyrotinib or afatinib were retrospectively enrolled. Pyrotinib yielded a longer median progression-free survival than afatinib (5.9 [95% CI, 3.8-13.0] vs. 4.0 months [95% CI, 1.9-6.3], P = 0.06) in these patients. Analysis of the genomic profiles before and after anti-HER2 targeted therapies identified de novo HER2 copy number gain and G518W mutation, as well as mutations involving DNA damage repair signaling, SWI–SNF complex, and epigenetic regulations as potential resistance mechanisms.

Conclusion

HER2-mutant NSCLC had different molecular features from HER2-amplified NSCLC, and its genomic profile was dependent of tumor stage. Pyrotinib had superior therapeutic effects than afatinib in HER2-altered NSCLC, although larger cohorts are warranted to validate it. HER2-dependent and -independent resistance mechanisms to afatinib and pyrotinib were unveiled.

Optimal therapy for concomitant EGFR and TP53 mutated non-small cell lung cancer: a real-world study

BACKGROUND

Non-small cell cancer (NSCLC) patients with concomitant epidermal growth factor receptor (EGFR) and TP53 mutations have a poor prognosis with the treatment of tyrosine kinase inhibitors (TKIs), and may benefit from a combination regimen preferentially. The present study aims to compare the benefits of EGFR-TKIs and its combination with antiangiogenic drugs or chemotherapy in patients with NSCLC harboring EGFR and TP53 co-mutation in a real-life setting.

METHODS

This retrospective analysis included 124 patients with advanced NSCLC having concomitant EGFR and TP53 mutations, who underwent next-generation sequencing prior to treatment. Patients were classified into the EGFR-TKI group and combination therapy group. The primary end point of this study was progression-free survival (PFS). The Kaplan-Meier (KM) curve was drawn to analyze PFS, and the differences between the groups were compared using the logarithmic rank test. Univariate and multivariate cox regression analysis was performed on the risk factors associated with survival.

RESULTS

The combination group included 72 patients who received the regimen of EGFR-TKIs combined with antiangiogenic drugs or chemotherapy, while the EGFR-TKI monotherapy group included 52 patients treated with TKI only. The median PFS was significantly longer in the combination group than in the EGFR-TKI group (18.0 months; 95% confidence interval [CI]: 12.1-23.9 vs. 7.0 months; 95% CI: 6.1-7.9; p < 0.001) with greater PFS benefit in TP53 exon 4 or 7 mutations subgroup. Subgroup analysis showed a similar trend. The median duration of response was significantly longer in the combination group than in the EGFR-TKI group. Patients with 19 deletions or L858R mutations both achieved a significant PFS benefit with combination therapy versus EGFR-TKI alone.

CONCLUSION

Combination therapy had a higher efficacy than EGFR-TKI alone for patients with NSCLC having concomitant EGFR and TP53 mutations. Future prospective clinical trials are needed to determine the role of combination therapy for this patient population.

RELAY, Ramucirumab plus Erlotinib (RAM+ERL) in Untreated Metastatic EGFR-Mutant NSCLC (EGFR+ NSCLC): Association between TP53 Status and Clinical Outcome

BACKGROUND

Ramucirumab plus erlotinib (RAM+ERL) demonstrated superior progression-free survival (PFS) in RELAY, a randomised Phase III trial in patients with untreated, metastatic, EGFR-mutated, non-small-cell lung cancer (EGFR+ NSCLC). Here, we present the relationship between TP53 status and outcomes in RELAY.

MATERIALS AND METHODS

Patients received oral ERL plus intravenous RAM (10 mg/kg IV) or placebo (PBO+ERL) every 2 weeks. Plasma was assessed by Guardant 360 next-generation sequencing and patients with any gene alteration detected at baseline were included in this exploratory analysis. Endpoints included PFS, overall response rate (ORR), disease control rate (DCR), DoR, overall survival (OS), safety, and biomarker analysis. The association between TP53 status and outcomes was evaluated.

RESULTS

Mutated TP53 was detected in 165 (42.7%; 74 RAM+ERL, 91 PBO+ERL) patients, wild-type TP53 in 221 (57.3%; 118 RAM+ERL, 103 PBO+ERL) patients. Patient and disease characteristics and concurrent gene alterations were comparable between those with mutant and wildtype TP53. Independent of treatment, TP53 mutations, most notably on exon 8, were associated with worse clinical outcomes. In all patients, RAM+ERL improved PFS. While ORR and DCR were comparable across all patients, DoR was superior with RAM+ERL. There were no clinically meaningful differences in the safety profiles between those with baseline TP53 mutation and wild-type.

CONCLUSION

This analysis indicates that while TP53 mutations are a negative prognostic marker in EGFR+ NSCLC, the addition of a VEGF inhibitor improves outcomes in those with mutant TP53. RAM+ERL is an efficacious first-line treatment option for patients with EGFR+ NSCLC, independent of TP53 status.

Meta-analysis of the prognostic impact of TP53 co-mutations in EGFR-mutant advanced non-small-cell lung cancer treated with tyrosine kinase inhibitors

PURPOSE

To assess the prognostic impact of TP53 mutations in EGFR-mutant advanced NSCLC patients treated with TKIs.

METHODS

Studies exploring the clinical outcomes of EGFR mutant/TP53 wild-type versus EGFR/TP53 co-mutant patients treated with TKIs were selected. Data were cumulated by adopting a fixed and random-effect model.

RESULTS

Overall, 29 trials were eligible. The PFS analysis showed that TP53 co-mutant group has shorter PFS versus EGFR mutant/TP53 wild-type group (HR = 1.67, 95% CI 1.51-1.83, heterogeneity I² =20%, p = 0.18). Patients affected by EGFR/TP53 co-mutant NSCLC have a higher chance of shorter OS versus EGFR mutant/TP53 wild type (HR= 1.89, 95% CI 1.67-2.14, heterogeneity I² = 21%; p = 0.19). The subgroup analysis showed no significant difference between first-second versus third-generation TKIs in both PFS and OS (p = 0.31, p = 0.08).

CONCLUSIONS

TP53 mutations represent a clinically relevant mechanism of resistance to EGFR-TKIs, regardless of their generation. A personalized therapeutical approach should be explored in dedicated clinical trials.

Efficacy and safety analyses of epidermal growth factor receptor tyrosine kinase inhibitors combined with chemotherapy in the treatment of advanced non-small-cell lung cancer with an EGFR/TP53 co-mutation

PURPOSE

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) combined with cytotoxic chemotherapy are highly effective in the treatment of advanced non-small-cell lung cancer (NSCLC) with EGFR mutations. The purpose of this study is to evaluate the efficacy and safety of this combination in advanced NSCLC patients with an EGFR/TP53 co-mutation.

METHODS

Ninety-five advanced NSCLC patients with an EGFR/TP53 co-mutation were enrolled in this study. Treatments with either EGFR-TKI monotherapy (T group, n = 61) or EGFR-TKI combined with chemotherapy (TC group, n = 34) were evaluated in relation to objective response rate (ORR), disease control rate (DCR), median time to progression (TTP), and median overall survival (OS).

RESULTS

There were no statistically significant differences in DCR between the treatment groups. The ORR was significantly improved in the TC group versus the T group (55.9% vs. 34.4%, P = 0.042). A higher median TTP was noted in TC group compared with T group (16.1 vs. 11.1 months, P = 0.002). Patients without brain metastases in TC group had a longer median OS than in T group (48.4 vs. 28.8 months, P = 0.003). However, there was a non-significant trend towards longer OS in TC group in the entire cohort (36.9 vs. 28.2 months, P = 0.078). Cox multivariate regression analysis showed that clinical stage, brain metastases, EGFR21 L858R mutation, and T790M status at first progression were independent risk factors for OS. However, the incidence of grade 3 or higher adverse events were higher in the TC group than in the T group (32.4% vs. 13.1%, P = 0.025).

CONCLUSION

Our study indicates that EGFR-TKIs combined with chemotherapy could significantly improve the ORR and TTP of advanced NSCLC patients with an EGFR/TP53 co-mutation. Combination therapy may be a promising treatment for advanced NSCLC patients with an EGFR/TP53 co-mutation without brain metastases.

Landscape of Savolitinib Development for the Treatment of Non-Small Cell Lung Cancer with MET Alteration-A Narrative Review

Non-small cell lung cancer (NSCLC) is increasingly being treated with targeted therapies. Savolitinib (Orpathys^®) is highly selective mesenchymal epithelial transition (MET)-tyrosine kinase inhibitor (TKI), which is conditionally approved in China for advanced NSCLC with MET exon 14 skipping mutations (METex14). This article summarizes the clinical development of savolitinib, as a monotherapy in NSCLC with METex14 mutation and in combination with epidermal growth factor receptor (EGFR) inhibitor in post EGFR-TKI resistance NSCLC due to MET-based acquired resistance. Preclinical models demonstrated anti-tumor activities in MET-driven cancer cell line and xenograft tumor models. The Phase Ia/Ib study established an optimized, recommended phase II dose in Chinese NSCLC patients, while TATTON study of savolitinib plus osimertinib in patients with EGFR mutant, MET-amplified and TKI-progressed NSCLC showed beneficial efficacy with acceptable safety profile. In a pivotal phase II study, Chinese patients with pulmonary sarcomatoid carcinoma, brain metastasis and other NSCLC subtype positive for METex14 mutation showed notable responses and acceptable safety profile with savolitinib. Currently, results from ongoing clinical trials are eagerly anticipated to confirm the efficacious and safety benefits of savolitinib as monotherapy and in combination with EGFR-TKI in acquired resistance setting in advanced NSCLC and its subtypes with MET alterations.

Molecular profiling identifies distinct subtypes across TP53 mutant tumors

Tumor protein 53 mutation (TP53mut) is one of the most important driver events facilitating tumorigenesis, which could induce a series of chain reactions to promote tumor malignant transformation. However, the malignancy progression patterns under TP53 mutation remain less known. Clarifying the molecular landscapes of TP53mut tumors will help us understand the process of tumor development and aid precise treatment. Here, we distilled genetic and epigenetic features altered in TP53mut cancers for cluster-of-clusters analysis. Using integrated classification, we derived 5 different subtypes of TP53mut patients. These subtypes have distinct features in genomic alteration, clinical relevance, microenvironment dysregulation, and potential therapeutics. Among the 5 subtypes, COCA3 was identified as the subtype with worst prognosis, causing an immunosuppressive microenvironment and immunotherapeutic resistance. Further drug efficacy research highlighted olaparib as the most promising therapeutic agents for COCA3 tumors. Importantly, the therapeutic efficacy of olaparib in COCA3 and immunotherapy in non-COCA3 tumors was validated via in vivo experimentation. Our study explored the important molecular events and developed a subtype classification system with distinct targeted therapy strategies for different subtypes of TP53mut tumors. These multiomics classification systems provide a valuable resource that significantly expands the knowledge of TP53mut tumors and may eventually benefit in clinical practice.

Prognostic impact of tumour mutational burden in resected stage I and II lung adenocarcinomas from a European Thoracic Oncology Platform Lungscape cohort

BACKGROUND

The primary objective of this study is to evaluate tumor mutational burden (TMB), its associations with selected clinicopathological and molecular characteristics as well as its clinical significance, in a retrospective cohort of surgically resected stage I-II lung adenocarcinomas, subset of the ETOP Lungscape cohort.

METHODS

TMB was evaluated on tumor DNA extracted from resected primary lung adenocarcinomas, based on FoundationOne®CDx (F1CDx) genomic profiling, centrally performed at the University Hospital Zurich. The F1CDx test sequences the complete exons of 324 cancer-related genes and detects substitutions, insertions and deletions (indels), copy number alterations and gene rearrangements. In addition, the genomic biomarkers TMB and microsatellite instability (MSI) are analyzed.

RESULTS

In the Lungscape cohort, TMB was assessed in 78 surgically resected lung adenocarcinomas from two Swiss centers (62 % males, 55 %/45 % stage I/II). Median TMB was 7.6 Muts/Mb, with TMB high (≥10 Muts/Mb) in 40 % of cases (95 %CI:29 %-52 %). The most frequently mutated genes were TP53/KRAS/EGFR/MLL2 detected in 58 %/38 %/33 %/30 % of samples, respectively. TMB was significantly higher among males (TMB high: 50 % vs 23 % in females, p = 0.032), as well as among current/former smokers (TMB high: 44 % vs 8 % in never smokers, p = 0.023). Furthermore, TMB was significantly higher in TP53 mutated than in non-mutated patients (TMB high: 60 % vs 12 %, p < 0.001), while it was higher in EGFR non-mutated patients compared to EGFR mutated (TMB high: 48 % vs 23 %, p = 0.049). At a median follow-up time of 56.1 months (IQR:38.8-72.0), none of the three outcome variables (OS, RFS, TTR) differed significantly by TMB status (all p-values > 5 %). This was also true when adjusting for clinicopathological characteristics.

CONCLUSIONS

While presence of TP53 mutations and absence of EGFR mutations are associated with high TMB, increased TMB had no significant prognostic impact in patients with resected stage I/II lung adenocarcinoma beyond T and N classification, in both unadjusted and adjusted analyses.

NSCLC patients with rare EGFR Ex19del/G724S mutation showed good response to afatinib combined with chemotherapy treatment: A two-case report

EGFR G724S mutation in exon 18 has been shown to be resistant to both first- and third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). However, we found a rare mutation of EGFR Ex19del/G724S in two patients with lung cancer who demonstrated a favorable response to the combination of afatinib and chemotherapy. Identified by next-generation sequencing (NGS), EGFR G724S was found from a primary and a secondary tumor biopsy, respectively. Treated with afatinib combined with chemotherapy, both patients responded well and achieved progression-free survival. Analysis of acquired mutations developed during treatment using afatinib revealed that the emergence of EGFR T790M or ALK fusion was the potential mechanism of afatinib resistance. Our study lends credence to treatment using afatinib combined with chemotherapy as a viable option for patients with Ex19del/G724S.

Efficacy Differences of First-line EGFR-TKIs Alone vs in Combination with Chemotherapy in Advanced Lung Adenocarcinoma Patients with Sensitive EGFR Mutation and Concomitant Non-EGFR Genetic Alterations

BACKGROUND

Epidermal growth factor receptor (EGFR) mutations are often associated with non-EGFR genetic alterations, which may be a reason for the poor efficacy of EGFR tyrosine kinase inhibitors (TKIs). Here we conducted this study to explore whether EGFR-TKIs combined with chemotherapy would benefit advanced lung adenocarcinoma patients with both sensitive EGFR mutation and concomitant non-EGFR genetic alterations.

METHODS

Cases of advanced lung adenocarcinoma with EGFR mutation combined with concomitant non-EGFR genetic alterations were retrospectively collected. And the patients were required to receive first-line EGFR-TKIs and chemotherapy combination or EGFR-TKIs monotherapy. Demographic, clinical and pathological data were collected, and the electronic imaging data were retrieved to evaluate the efficacy and time of disease progression. Survival data were obtained through face-to-face or telephone follow-up. The differences between the two groups in objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and overall survival (OS) were investigated.

RESULTS

107 patients were included, including 63 cases in the combination group and 44 cases in the monotherapy group. The ORR were 78% and 50% (P=0.003), and DCR were 97% and 77% (P=0.002), respectively. At a median follow-up of 13.7 mon, a PFS event occurred in 38.1% and 81.8% of patients in the two groups, with median PFS of 18.8 mon and 5.3 mon, respectively (P<0.000,1). Median OS was unreached in the combination group, and 27.8 mon in the monotherapy group (P=0.31). According to the Cox multivariate regression analysis, combination therapy was an independent prognostic factor of PFS CONCLUSIONS: In patients with EGFR-mutant advanced lung adenocarcinoma with concomitant non-EGFR genetic alterations, combination of TKIs and chemotherapy was significantly superior to EGFR-TKIs monotherapy, which should be the preferred treatment option.

TP53 Co-Mutations in Advanced EGFR-Mutated Non-Small Cell Lung Cancer: Prognosis and Therapeutic Strategy for Cancer Therapy

Lung cancer is the leading cause of cancer-related deaths worldwide. As the most prevalent molecular mutation subtypes in non-small cell lung cancer (NSCLC), EGFR-TKIs are currently a standard first-line therapy for targeting the mutated EGFR in advanced NSCLC patients. However, 20-30% of this subset of patients shows primary resistance to EGFR-TKIs. Patients with co-mutations of EGFR and several other genes have a poor response to EGFR-TKIs, whereas the prognostic and predictive significance of EGFR/TP53 co-mutation in NSCLC patients remains controversial. Meanwhile, little is known about how to choose an optimal therapeutic strategy for this subset of patients. Presently, no drugs targeting TP53 mutations are available on the market, and some p53 protein activators are in the early stage of clinical trials. A combination of EGFR-TKIs with antiangiogenic agents or chemotherapy or other agents might be a more appropriate strategy to tackle the problem. In this review, we describe the prognostic and predictive value of EGFR/TP53 co-mutation in NSCLC patients, investigate the mechanisms of this co-mutation affecting the response to EGFR-TKIs, and further explore optimal regimens effectively to prolong the survival time of the NSCLC patients harboring this co-mutation.

The Role of TP53 Mutations in EGFR-Mutated Non-Small-Cell Lung Cancer: Clinical Significance and Implications for Therapy

Simple Summary

Non-Small-Cell Lung Cancer (NSCLC) is the primary cause of cancer-related death worldwide. Patients carrying Epidermal Growth Factor Receptor (EGFR) mutations usually benefit from targeted therapy treatment. Nonetheless, primary or acquired resistance mechanisms lead to treatment discontinuation and disease progression. Tumor protein 53 (TP53) mutations are the most common mutations in NSCLC, and several reports highlighted a role for these mutations in influencing prognosis and responsiveness to EGFR targeted therapy. In this review, we discuss the emerging data about the role of TP53 in predicting EGFR mutated NSCLC patients’ prognosis and responsiveness to targeted therapy.

Abstract

Non-Small-Cell Lung Cancer (NSCLC) is the primary cause of cancer-related death worldwide. Oncogene-addicted patients usually benefit from targeted therapy, but primary and acquired resistance mechanisms inevitably occur. Tumor protein 53 (TP53) gene is the most frequently mutated gene in cancer, including NSCLC. TP53 mutations are able to induce carcinogenesis, tumor development and resistance to therapy, influencing patient prognosis and responsiveness to therapy. TP53 mutants present in different forms, suggesting that different gene alterations confer specific acquired protein functions. In recent years, many associations between different TP53 mutations and responses to Epidermal Growth Factor Receptor (EGFR) targeted therapy in NSCLC patients have been found. In this review, we discuss the current landscape concerning the role of TP53 mutants to guide primary and acquired resistance to Tyrosine-Kinase Inhibitors (TKIs) EGFR-directed, investigating the possible mechanisms of TP53 mutants within the cellular compartments. We also discuss the role of the TP53 mutations in predicting the response to targeted therapy with EGFR-TKIs, as a possible biomarker to guide patient stratification for treatment.

Patients harboring uncommon EGFR exon 19 deletion-insertion mutations respond well to first-generation EGFR inhibitors and osimeritinib upon acquisition of T790M

Background

In the existing next generation sequencing (NGS) system, epidermal growth factor receptor (EGFR) exon 19 deletion-insertion (19delins) is still interpreted into the category of EGFR exon 19 deletion (19del). However, the controversy exists whether the two mutation types have the similar responses and resistant mechanisms to first-generation EGFR tyrosine kinase inhibitor (TKI) in non-small cell lung cancer (NSCLC) patients.

Methods

We successively and retrospectively reviewed the NGS data of 3054 patients diagnosed as advanced NSCLC from November 2017 to September 2020. Finally, 41 patients with EGFR 19delins mutation and 41 patients with EGFR 19del mutation who received first-generation EGFR TKIs as first-line therapy were included in the study.

Results

A total of 17 genotypes were identified in this study, including L747_P753delinsS (10/41), L747_A750delinsP (9/41), L747_T751delinsP (6/41) and E746_S752delinsV (3/41). Under the same baseline characteristics, the population of EGFR 19delins respond well to first line EGFR TKIs as well as those of EGFR 19del, with little difference in median progression-free survival (mPFS): 10.4 months vs. 13.1 months, p = 0.1076). Interestingly, patients with L747_T751delinsP seem to have a better mPFS than others (18.7 months vs. 13.1 months, p = 0.035). After the disease progression, both EGFR 19delins and EGFR 19del had similar rates of developing EGFR T790M mutation resistance (45.8% vs. 57.8%), and those receiving osimeritinib as second-line treatment obtain the similar survival benefits (mPFS: 12.0 months vs. 12.2 months (p = 0.97).

Conclusions

This retrospective cohort study furnish the evidence that therapeutic responses and survival of untreated NSCLC population with EGFR 19delins mutation are equal to those with common EGFR 19del mutation after administration of EGFR TKIs therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08942-x.

Genomic signatures define three subtypes of EGFR-mutant stage II-III non-small-cell lung cancer with distinct adjuvant therapy outcomes

The ADJUVANT study reported the comparative superiority of adjuvant gefitinib over chemotherapy in disease-free survival of resected EGFR-mutant stage II–IIIA non-small cell lung cancer (NSCLC). However, not all patients experienced favorable clinical outcomes with tyrosine kinase inhibitors (TKI), raising the necessity for further biomarker assessment. In this work, by comprehensive genomic profiling of 171 tumor tissues from the ADJUVANT trial, five predictive biomarkers are identified (TP53 exon4/5 mutations, RB1 alterations, and copy number gains of NKX2-1, CDK4, and MYC). Then we integrate them into the Multiple-gene INdex to Evaluate the Relative benefit of Various Adjuvant therapies (MINERVA) score, which categorizes patients into three subgroups with relative disease-free survival and overall survival benefits from either adjuvant gefitinib or chemotherapy (Highly TKI-Preferable, TKI-Preferable, and Chemotherapy-Preferable groups). This study demonstrates that predictive genomic signatures could potentially stratify resected EGFR-mutant NSCLC patients and provide precise guidance towards future personalized adjuvant therapy.

Adjuvant gefitinib improves outcomes in non-small cell lung cancer (NSCLC) patients compared to chemotherapy, but not in all cases. Here, the authors find genomic biomarkers of response to gefitinib in NSCLC patients from the ADJUVANT trial, and propose a score to stratify them by potential benefit from the treatment.

A Large Real-World Study on the Effectiveness of the Combined Inhibition of EGFR and MET in EGFR-Mutant Non-Small-Cell Lung Cancer After Development of EGFR-TKI Resistance

Background

MET proto-oncogene amplification (amp) is an important mechanism underlying acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). However, the optimal treatment strategy after acquiring MET-amp-mediated EGFR-TKI resistance remains controversial. Our study compared three treatment strategies for patients with EGFR-mutant non-small-cell lung cancer (NSCLC) who were detected with MET-amp at EGFR-TKI progression using next-generation sequencing.

Methods

Of the 70 patients included in the study, 38 received EGFR-TKI + crizotinib, 10 received crizotinib monotherapy, and 22 received chemotherapy. Clinical outcomes and molecular profiles were analyzed.

Results

The objective response rate was 48.6% for EGFR-TKI + crizotinib group, 40.0% for crizotinib monotherapy group, and 18.2% for chemotherapy group. Patients who received EGFR-TKI + crizotinib had significantly longer progression-free survival than those who received crizotinib or chemotherapy (5.0 vs. 2.3 vs. 2.9 months, p = 0.010), but overall survival was comparable (10.0 vs. 4.1 vs. 8.5 months, p = 0.088). TP53 mutation (58.5%) and EGFR-amp (42.9%) were frequent concurrent mutations of the cohort. Progression-free survival was significantly longer for patients with either concurrent TP53 mutation (n = 17) (6.0 vs. 2.3 vs. 2.9 months, p = 0.009) or EGFR-amp (n = 13) (5.0 vs. 1.2 vs. 2.4 months, p = 0.016) in the EGFR-TKI + crizotinib group than the other two regimen. Potential acquired resistance mechanisms to EGFR-TKI + crizotinib included EGFR-T790M (n = 2), EGFR-L718Q (n = 1), EGFR-S645C (n = 1), MET-D1228H (n = 1), BRAF-V600E (n = 1), NRAS-Q61H (n = 1), KRAS-amp (n = 1), ERBB2-amp (n = 1), CDK4-amp (n = 1), and MYC-amp (n = 1).

Conclusion

Our study provides real-world clinical evidence from a large cohort that simultaneous inhibition of EGFR and MET could be a more effective therapeutic strategy for patients with MET-amp acquired from EGFR-TKI therapy.

Differences in genetics and microenvironment of lung adenocarcinoma patients with or without TP53 mutation

Background

Differences in genetics and microenvironment of LUAD patients with or without TP53 mutation were analyzed to illustrate the role of TP53 mutation within the carcinogenesis of LUAD, which will provide new concepts for the treatment of LUAD.

Methods

In this study, we used genetics and clinical info from the TCGA database, including somatic mutations data, RNA-seq, miRNA-seq, and clinical data. More than one bioinformatics tools were used to analyze the unique genomic pattern of TP53-related LUAD.

Results

According to TP53 gene mutation status, we divided the LUAD patients into two groups, including 265 in the mutant group (MU) and 295 in the wild-type group (WT). 787 significant somatic mutations were detected between the groups, including mutations in titin (TTN), type 2 ryanodine receptor (RYR2) and CUB and Sushi multiple domains 3(CSMD3), which were up-regulated in the MU. However, no significant survival difference was observed. At the RNA level, we obtained 923 significantly differentially expressed genes; in the MU, α-defensin 5(DEFA5), pregnancy-specific glycoprotein 5(PSG5) and neuropeptide Y(NPY) were the most up-regulated genes, glucose-6-phosphatase (G6PC), alpha-fetoprotein (AFP) and carry gametocidal (GC) were the most down-regulated genes. GSVA analysis revealed 30 significant pathways. Compared with the WT, the expression of 12 pathways in the mutant group was up-regulated, most of which pointed to cell division. There were significant differences in tumor immune infiltrating cells, such as Macrophages M1, T cells CD4 memory activated, Mast cells resting, and Dendritic cells resting. In terms of immune genes, a total of 35 immune-related genes were screened, of which VGF (VGF nerve growth factor inducible) and PGC (peroxisome proliferator-activated receptor gamma coactivator) were the most significant up-regulated and down-regulated genes, respectively. Research on the expression pattern of immunomodulators found that 9 immune checkpoint molecules and 6 immune costimulatory molecules were considerably wholly different between the two groups.

Conclusions

Taking the mutant group as a reference, LUAD patients in the mutant group had significant differences in somatic mutations, mRNA-seq, miRNA-seq, immune infiltration, and immunomodulators, indicating that TP53 mutation plays a crucial role in the occurrence and development of LUAD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01671-8.

Intra-tumor and Inter-tumor Heterogeneity in MET Exon 14 Skipping Mutations and Co-mutations in Pulmonary Pleomorphic Carcinomas

BACKGROUND

MET exon 14 skipping mutation is a driver mutation in lung cancer and is highly enriched in pulmonary pleomorphic carcinomas (PPCs). Whether there is intratumor or intertumor heterogeneity in MET exon 14 skipping status or in co-occurring genetic alterations in lung cancers driven by MET exon 14 skipping is unknown.

METHODS

We analyzed tumor specimens obtained from 23 PPC patients (10 autopsied and 13 surgically resected). MET exon 14 skipping was detected by RT-PCR. For patients with MET exon 14 skipping mutation, further analyses were performed. Genomic DNA (gDNA) was extracted from various histological components for each patient who underwent surgical resection (to assess intratumor heterogeneity). In autopsied patients, gDNA and total RNA were extracted from all metastatic lesions (to assess intertumor heterogeneity).

RESULTS

MET exon 14 skipping mutation was detected in 4 patients (4/23, 17.4%): two surgically resected and two autopsied patients. We found no intratumor or intertumor heterogeneity in MET exon 14 skipping mutation status in these patients. We observed intratumor and intertumor heterogeneity in the copy number variations and/or mutational status of cancer-related genes; some of these differences may have an impact on MET tyrosine kinase inhibitor (TKI) efficacy.

CONCLUSION

In our exploratory analysis of four cases, we observed that MET exon 14 skipping mutations are distributed homogeneously throughout histological components and between metastatic lesions. Our results also suggest that there is marked intertumor and intratumor heterogeneity in co-occurring genetic alterations, and therapeutic implications of such heterogeneity should be evaluated in future studies.

The ratio of T790M to EGFR-activating mutation predicts response of osimertinib in 1st or 2nd generation EGFR-TKI-refractory NSCLC

The most frequent mechanism of resistance after 1st/2nd-generation (G) epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) is secondary point mutation Thr790Met (T790M) in EGFR. Afatinib followed by osimertinib (Afa group) may provide better outcomes for T790M-positive non-small cell lung cancer (NSCLC) than 1st-G EGFR-TKI followed by osimertinib (1st-G group). We studied 111 consecutive NSCLC patients with T790M mutation treated with osimertinib after progression following 1st/2nd-G EGFR-TKI between March 28, 2016 and March 31, 2018. We analyzed the ratio of T790M to EGFR-activating mutation (T790M ratio) in post EGFR-TKI resistance re-biopsy tissue using droplet digital polymerase chain reaction. And investigated whether afatinib purified the T790M mutation more than 1st-G EGFR-TKI. Among 60 patients with preserved re-biopsy tissue, we analyzed 38 having adequate DNA content. The response rate in Afa group was 81.8% (n = 11) and 1st-G group was 85.2% (n = 27). The mean T790M ratio in total population was 0.3643. The ratio in those with response to osimertinib was significantly higher than in the non-responders (0.395, 0.202; p = 0.0231) and was similar in Afa and 1st-G group (0.371, 0.362; p = 0.9693). T790M ratio significantly correlated with osimertinib response and was similar between the 1st/2nd-G EGFR-TKIs in 1st/2nd-G EGFR-TKI-refractory tumors.