Treatment with Anlotinib After Chemotherapy and EGFR-TKI Resistance in Lung Adenosquamous Carcinoma with Concurrent EGFR and PIK3CA Mutations: A Case Report and Literature Review

Highly consistency of PIK3CA mutation spectrum between circulating tumor DNA and paired tissue in lung cancer patients

Background

Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha ( PIK3CA) mutations are associated with drug resistance and prognosis in lung cancer; however, the consistency and clinical value of PIK3CA mutations between tissue and liquid samples are unknown.

Methods

Circulating tumor DNA (ctDNA) and matched tumor tissue samples from 405 advanced lung cancer patients were collected at Jilin Cancer Hospital between 2018 and 2022, and the PIK3CA mutation status was sequenced using next-generation sequencing based on a 520 gene panel. The viability of different mutant lung cancer cells was detected using MTT assay.

Results

PIK3CA mutations were detected in 46 (5.68 %) of 810 lung cancer samples, with 21 (5.19 %) of 405 plasma samples and 25 (6.17 %) of 405 matched tissues. p.Glu542Lys, p.Glu545Lys, and p.His1047Arg were the most common mutation types of PIK3CA in both the ctDNA and tissue samples. The concordance of PIK3CA mutations was 97.53 % between ctDNA and matched tissues (kappa: 0.770, P = 0.000), with sensitivity/true positive rate of 72.0 %, specificity/true negative rate of 99.2 %, and negative predictive value and positive predictive value of 0.982 and 0.857, respectively (AUC = 0.856, P = 0.000). Furthermore, the concordance of PIK3CA mutations was 98.26 % in lung adenocarcinoma and 96.43 % in lung squamous cell carcinoma. TP53 and EGFR were the most common concomitant mutations in ctDNA and tissues. Patients with PIK3CA mutations showed a high tumor mutational burden (TMB) (P < 0.001) and a significant correlation between bTMB and tTMB (r = 0.5986, P = 0.0041). For the tPIK3CAmut/ctDNA PIK3CAmut cohort, PI3K pathways alteration was associated with male sex (P = 0.022), old age (P = 0.007), and smoking (P = 0.001); tPIK3CAmut/ctDNA PIK3CAwt patients harbored clinicopathological factors of adenocarcinoma stage IV, with low PS score (≤1) and TMB.

Conclusion

This study showed that ctDNA is highly concordant and sensitive for identifying PIK3CA mutations, suggesting that PIK3CA mutation detection in liquid samples may be an alternative clinical practice for tissues.

Efficacy of epidermal growth factor receptor-tyrosine kinase inhibitor for lung adenosquamous cell carcinoma harboring EGFR mutation: a retrospective study and pooled analysis

Objectives

To explore the efficacy of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) on lung adenosquamous cell carcinoma (ASC) with EGFR mutation.

Methods

Efficacy of EGFR-TKIs in the treatment of advanced or recurrent lung ASC with EGFR mutations was assessed retrospectively in 44 patients. Pooled analysis of 74 patients using EGFR-TKIs, including 30 patients selected from 11 publications, was conducted.

Results

In our retrospective research, patients treated with EGFR-TKI in ASC with EGFR mutations had objective response rate (ORR) of 54.5%, disease control rate (DCR) of 79.5%, median progression free survival (mPFS) of 8.8 months, and median overall survival (mOS) of 19.43 months, respectively. A pooled analysis reveals ORR, DCR, mPFS, and mOS are, respectively, 63.4%, 85.9%, 10.00 months, and 21.37 months for ASC patients. In patients with deletions in exon 19 and exon 21 L858R mutations, mPFS (11.0 versus 10.0 months, P=0.771) and mOS (23.67 versus 20.33 months, P=0.973) were similar. Erlotinib or gefitinib-treated patients had an overall survival trend that was superior to that of icotinib-treated patients.

Conclusions

ASC harboring EGFR mutations can be treated with EGFR-TKI in a similar manner to Adenocarcinoma (ADC) harboring EGFR mutations. There is still a need for further investigation to identify the separate roles of ASC's two components in treating EGFR.

PIK3CA mutation as an acquired resistance driver to EGFR-TKIs in non-small cell lung cancer: Clinical challenges and opportunities

Epithelial growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have significantly enhanced the treatment outcomes in non-small cell lung cancer (NSCLC) patients harboring EGFR mutations. However, the occurrence of acquired resistance to EGFR-TKIs is an unavoidable outcome observed in these patients. Disruption of the PI3K/AKT/mTOR signaling pathway can contribute to the emergence of resistance to EGFR TKIs in lung cancer. The emergence of PIK3CA mutations following treatment with EGFR-TKIs can lead to resistance against EGFR-TKIs. This review provides an overview of the current perspectives regarding the involvement of PI3K/AKT/mTOR signaling in the development of lung cancer. Furthermore, we outline the state-of-the-art therapeutic strategies targeting the PI3K/AKT/mTOR signaling pathway in lung cancer. We highlight the role of PIK3CA mutation as an acquired resistance mechanism against EGFR-TKIs in EGFR-mutant NSCLC. Crucially, we explore therapeutic strategies targeting PIK3CA-mediated resistance to EGFR TKIs in lung cancer, aiming to optimize the effectiveness of treatment.

MYH16 upregulation is associated with lung adenocarcinoma aggressiveness and immune infiltration

Myosin heavy chain 16 (MYH16) may significantly affect cell cycle progression. Nevertheless, there is a lack of evidence about the clinical relevance of MYH16 upregulation in pan cancers, including lung adenocarcinoma (LUAD). MYH16 expression patterns were evaluated in various bioinformatics databases using The Cancer Genome Atlas data set. Clinical and pathological factor data were employed to risk-stratify patients. The Kaplan-Meier plotter approach was used to estimate survival rates. Tumor immune infiltration was explored via the TIMER tool, and gene set enrichment analysis (GSEA) was used to identify the pathways involved in MYH16 upregulation. The results showed that MYH16 was abnormally upregulated in pan cancers, including LUAD. MYH16 expression induction in LUAD was found to be related to the tumor stage. Furthermore, MYH16 upregulation was correlated with LUAD development and worse overall survival, particularly in women. Notably, MYH16 overexpression in LUAD tissues corresponded to the amount of immune infiltration in the tumor. Additionally, univariate Cox hazard regression analysis revealed that MYH16 may be an independent prognostic indicator for LUAD. Furthermore, a nomogram was constructed according to MYH16 expression and clinical characteristics. BMP6 expression deficiency may be a key factor contributing to MYH16 upregulation in LUAD. Finally, GSEA demonstrated that MYH16 might mediate meiosis and gene silencing through RNA signaling pathways. This study, for the first time, showed that MYH16 upregulation in LUAD is associated with various risk factors, increased cancer aggressiveness, enhanced infiltration of tumor immune cells, and reduced survival rates.

The potential therapeutic regimen for overcoming resistance to osimertinib due to rare mutations in NSCLC

The mechanisms of osimertinib resistance have not been well characterized. We conducted next-generation sequencing to recognize novel resistance mechanism and used cell line-derived xenograft (CDX) and patient-derived xenograft (PDX) models to evaluate the anti-proliferative effects of aspirin in vivo and in vitro. We observed that PIK3CG mutations led to acquired resistance to osimertinib in a patient and further confirmed that both PIK3CG and PIK3CA mutations caused osimertinib resistance. Mechanistically, the expression of PI3Kγ or PI3Kα was up-regulated after PIK3CG or PIK3CA lentivirus transfection, respectively, and which can be effectively suppressed by aspirin. Lastly, our results from in vivo studies indicate that aspirin can reverse osimertinib resistance caused by PIK3CG or PIK3CA mutations in both CDX and PDX models. Herein, we first confirmed that mutations in PIK3CG can lead to resistance to osimertinib, and the combined therapy may be a strategy to reverse PIK3CG/PIK3CA mutation-induced osimertinib resistance.

Comprehensive analyses of genomic features and mutational signatures in adenosquamous carcinoma of the lung

Adenosquamous carcinoma (ASC) of the lung is a relatively rare tumor with strong aggressiveness and poor prognosis. The analysis of mutational signatures is becoming routine in cancer genomics and has implications for pathogenesis, classification, and prognosis. However, the distribution of mutational signatures in ASC patients has not been evaluated. In this study, we sought to reveal the landscape of genomic mutations and mutational signatures in ASC. Next-generation sequencing (NGS) technology was used to retrieve genomic information for 124 ASC patients. TP53 and EGFR were the most prevalent somatic mutations observed, and were present in 66.9% and 54.8% of patients, respectively. CDKN2A (21%), TERT (21%), and LRP1B (18.5%) mutations were also observed. An analysis of gene fusion/rearrangement characteristics revealed a total of 64 gene fusions. The highest frequency of variants was determined for ALK fusions, with six ALK-EML4 classical and two intergenic ALK fusions, followed by three CD74-ROS1 fusions and one ROS1-SYN3 fusion. EGFR 19del (45.6%), and EGFR L858R (38.2%) and its amplification (29.4%) were the top three EGFR mutations. We extracted mutational signatures from NGS data and then performed a statistical analysis in order to search for genomic and clinical features that could be linked to mutation signatures. Amongst signatures cataloged at COSMIC, the most prevalent, high-frequency base changes were for C > T; and the five most frequent signatures, from highest to lowest, were 2, 3, 1, 30, and 13. Signatures 1 and 6 were determined to be associated with age and tumor stage, respectively, and Signatures 22 and 30 were significantly related to smoking. We additionally evaluated the correlation between tumor mutational burden (TMB) and genomic variations. We found that mutations ARID2, BRCA1, and KEAP1 were associated with high TMB. The homologous recombination repair (HRR) pathway-related gene mutation displayed a slightly higher TMB than those without mutations. Our study is the first to report comprehensive genomic features and mutational signatures in Chinese ASC patients. Results obtained from our study will help the scientific community better understand signature-related mutational processes in ASC.