[Analysis of the Effcacy and Safety of Amivantamab in Non-small Cell Lung Cancer Patients with EGFR/MET Gene Abnormalities: A Single Center's Experience]

BACKGROUND

Epidermal growth factor receptor (EGFR) and cellular-mesenchymal to epithelial transition factor (c-Met) are widely expressed on cancer cells. There is a synergistic effect of EGFR and HGF/c-Met pathways on proliferation, downstream activation of signal transduction and an additive effect. Studies show that combination of both signaling pathways could potentially be targeted in a synergistic fashion. Amivantamab, a bispecific monoclonal antibody targeting EGFR and c-Met, yielded robust and durable responses in a variety of clinicals trials. However, few researches have reported its efficacy in Chinese non-small cell lung cancer (NSCLC) patients. This study was conducted to evaluate the effectiveness and tolerance of Amivantamab in NSCLC patients with EGFR/MET gene abnormalities at Peking University Cancer Hospital.

METHODS

The study enrolled NSCLC patients who received Amivantamab in our hospital between August 2020 and December 2021, and analyzed the response, survival, and treatment-related adverse events.

RESULTS

Fifteen patients were enrolled in this research, and six of them received Amivantamab treatment and the other nine patients received Amivantamab plus Lazertinib treatment. The rates of partial response (PR), stable disease (SD), and progressive disease (PD) were 46.7% (7/15), 46.7% (7/15) and 6.7% (1/15), respectively. The overall response rate (ORR) and disease control rate (DCR) were 28.6% (2/7) and 100.0% (7/7) in seven patients with EGFR exon 20 insertion, respectively. The ORR and DCR were 40.0% (2/5) and 100.0% (5/5) in five post-osimertinib EGFR-mutant patients, respectively. After a median follow-up of 8.7 months, the median progression-free survival and overall survival were not reached. The most common treatment-related adverse events were rash (86.7%), paronychia (80.0%), and infusion-related reactions (60.0%), and most of them were graded as 1 to 2. Grade 3 to 4 adverse events included rash (33.3%), alanine aminotransferase elevation (13.3%), gamma-glutamyl transpeptidase elevation (13.3%), peripheral edema (6.7%), thromboembolism (6.7%), interstitial lung disease (6.7%), and thrombocytopenia (6.7%).

CONCLUSIONS

Amivantamab was effective in Chinese NSCLC patients with EGFR exon 20 insertion and post-Osimertinib EGFR-mutant patients, similar to the results of clinical trials conducted in western countries. Amivantamab was well tolerated and emphases should be put on adverse events such as rash, paronychia, and infusion-related reactions.

Evaluation of Light-Emitting Diodes' Effects on the Expression Level of P53 and EGFR in the Gingival Tissues of Albino Rats

Background and objectives: The light-curing unit is considered an essential piece of equipment in every dental office. This study was conducted to evaluate the effect of Light-Emitting Diodes (LEDs) by the light cure (LC) device on gingival tissues of albino rats histologically and by regarding the expression of P53 and epidermal growth factor receptor (EGFR). Materials and methods: Gingival tissues of the rats were exposed to LEDs for 30 s with an interval of 30 s for periods of 2 and 5 min and were examined after two and four weeks of light exposure. After the set time, histological sections were studied and the P53 and EGFR expressions were evaluated immunohistochemically and by molecular methods. Results: Mild hyperplasia and mild inflammatory response were detected in higher rates after two weeks of exposure when compared to 4 weeks postexposure. Whereas fibrosis was found at a higher rate after four weeks than that found after two weeks postexposure, parakeratosis was seen only in the group that was exposed for 5 min to LC and when biopsies were taken after 2 weeks. We found that the immunohistochemical expression of P53 was not changed. Similarly, the alteration of EGFR expression was statistically nonsignificant (p > 0.05) when compared to the control group. The data obtained from the qRT-PCR reaction was analyzed using the comparative CT (2^−ΔΔCT) method. Statistically, there was no significant difference in the expression of EGER and P53 gene transcripts. Conclusions: LED causes no serious alteration in P53 and EGFR expression, and only trivial histopathological changes occurred, most of which recovered after a 4-week interval.

AXL degradation in combination with EGFR-TKI can delay and overcome acquired resistance in human non-small cell lung cancer cells

Acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) has been a major obstacle in the treatment of non-small cell lung cancer (NSCLC) patients. AXL has been reported to mediate EGFR-TKIs. Recently, third generation EGFR-TKI osimertinib has been approved and yet its acquired resistance mechanism is not clearly understood. We found that AXL is involved in both gefitinib and osimertinib resistance using in vitro and in vivo model. In addition, AXL overexpression was correlated with extended protein degradation rate. We demonstrate targeting AXL degradation is an alternative route to restore EGFR-TKIs sensitivity. We confirmed that the combination effect of YD, an AXL degrader, and EGFR-TKIs can delay or overcome EGFR-TKIs-driven resistance in EGFR-mutant NSCLC cells, xenograft tumors, and patient-derived xenograft (PDX) models. Therefore, combination of EGFR-TKI and AXL degrader is a potentially effective treatment strategy for overcoming and delaying acquired resistance in NSCLC.

The role of the cytopathologist in subtyping and epidermal growth factor receptor testing in non-small cell lung cancer: An institutional experience

OBJECTIVE

Approximately 10% of non-small-cell lung cancer (NSCLC) remains unclassifiable as NSCLC-not otherwise specified (NOS), after using a panel of immunomarkers. The present study was undertaken to assess sensitivity and specificity of immunomarkers in sub-typing NSCLC on fine needle aspiration cytology (FNAC). Epidermal growth factor receptor (EGFR) mutations were also detected in these samples.

METHODS

Sixty cases of NSCLC including 15 squamous cell carcinoma (SCC), 15 adenocarcinomas (ADC) and 30 NSCLC-NOS reported on FNAC were included in the study. A panel of CK7, CK5/6, TTF-1 and p63 was applied in these cases. DNA was extracted from 54 cases including 14 effusion samples, and EGFR mutations were detected.

RESULTS

Classic ADC cases (n=15) showed 73.3% TTF-1 positivity and 100% CK7 positivity. Two cases of ADC showed aberrant expression of p63 and 2 cases showed CK5/6 positivity. 80% of classic SCC cases (n=15) showed strong nuclear p63 positivity and 86.6% were positive for CK5/6. TTF-1 was seen exclusively in ADC cases. Immunohistochemistry (IHC) using two immunomarkers (TTF-1 and p63) helped in subtyping 24/30(80%) cases of NSCLC. EGFR mutations were detected in 9/54 (16.7%) cases, and the most common mutation was short in-frame deletion in Exon 19.

CONCLUSIONS

More than 90% of NSCLC can be sub-typed on cytology samples with the help of immunochemistry. The sensitivity of TTF-1, p63, CK5/6 and CK7 was 73.3%, 80%, 100% and 100%, respectively. The specificity of TTF-1, p63, CK5/6 and CK7 was 100%, 86.6%, 86.6% and 93.3%, respectively. TTF-1 is highly specific, and almost 80% of NSCLC-NOS cases can be sub-typed using TTF-1 and p63. EGFR mutations can be detected in cytology samples, and 16.7% samples were positive for EGFR mutations.

Screening for EGFR mutations in lung cancer, a report from India

Epidermal growth factor receptor (EGFR) is one of the targeted molecular markers in many cancers including the lung malignancy. Genetic modifications such as deletions, insertions and Single Nucleotide Polymorphisms in the tyrosine kinase (TK) domain of EGFR is a common feature observed in most lung cancers. Gefitinib and erlotinib are commonly available therapeutic drugs which act as specific inhibitors for the tyrosine kinase domain of EGFR and associated with EGFR mutations in exons 18-21. However the prevalence of mutation varies among ethnicity, grade, age and gender. This is the first report on the prevalence of EGFR mutation in non-small cell lung cancer patients using DNA obtained from samples such as biopsy/cytology/pleural fluid and Fine Needle Aspiration (FNA), across India. We have screened for 29 somatic mutations which span exons 18, 19, 20 and 21 of EGFR gene using Scorpion probe based ARMS-PCR technique. DNA from 220 NSCLC tissue samples were analyzed for EGFR mutations and mutations were detected in 51.8% of the study population. Among the mutant positive cases, the deletions in exon 19 (52%) and a missense mutation L858R in exon 21 (26%) were most predominant. There was a significant increase in overall mutations (p=0.01) as a function of age, mutation in exons 19 and 21 together (p=0.003), mutations in exons 18, 19 and 21 (p=0.04) and mutations in exons 18 and 19 (p=0.03) in females. Mutations did not seem to significantly correlate metastases or disease progression. Mutations in exons [19] and 21 together were significant in non-smokers compared to smokers (p=0.01) using Mann-Whitney tests. The study suggests high prevalence of EGFR positivity in NSCLC in Indian sub-population and provides opportunities for targeted therapies for this group.

The Potential Value of EGFR and P53 Immunostaining in Tumors of the Urinary Bladder

The expression of EGFR and p53 has not been adequately studied as a prognostic tool in urinary bladder tumors. We analyzed 74 bladder cancer samples from Egypt for EGFR and p53 expression using immunohistochemistry. The tumors were of different histological types, grades and clinical stages, and with established lymph node status. Almost 61% of the tumors showed positive membranous EGFR expression and 74.3% had positive nuclear staining of p53. Analysis of correlation of the IHC staining with clinical variables showed a significant correlation only between EGFR expression and histological type (p=0.002, ANOVA), in that the expression was higher in squamous cell carcinomas than in other histological types. There were no significant correlations between p53 or EGFR with the other clinicopathological variables, including age, sex, staging, grading, and lymph node status. Further studies are needed to determine if EGFR and p53 might be used as prognostic tools in bladder cancer.

Role of DMP1 and its future in lung cancer diagnostics

Lung cancer is the most lethal carcinoma worldwide. Mutations of p53, inactivation of p16(INK4a), and overexpression of cyclins E, A and B are independently associated with poor prognoses of patients, while the prognostic value of cyclin D1 or RB expression is inconclusive. Cyclin D binding myb-like protein 1 (Dmp1) encodes a DNA binding protein that receives signals from oncogenic Ras and functions as a tumor suppressor by activating the Arf-p53 [corrected] pathway. Dmp1 has been shown to be haplo-insufficient for tumor suppression in mouse models including K-ras-mediated lung carcinogenesis. The human DMP1 gene is located on chromosome 7q21, and our recent results revealed that the hDMP1 gene is deleted, but not mutated or silenced, in approximately 40 % of human non-small-cell lung carcinomas. These cases typically retained wild-type ARF and p53 and expressed very low levels of the hDMP1 protein. Thus, hDMP1 loss could be a novel diagnostic marker for non-small-cell lung carcinomas.