A Screening Method for the ALK Fusion Gene in NSCLC

Lung cancer research has recently made significant progress in understanding the molecular pathogenesis of lung cancer and in developing treatments for it. Such achievements are directly utilized in clinical practice. Indeed, the echinoderm microtubule-associated protein-like 4–anaplastic lymphoma kinase (ALK) fusion gene was first described in non-small cell lung cancer in 2007, and a molecularly targeted drug against the fusion was approved in 2011. However, lung cancer with the ALK fusion constitutes only a small fraction of lung cancers; therefore, efficient patient selection is crucial for successful treatment using the ALK inhibitor. Currently, RT-PCR, fluorescent in situ hybridization (FISH), and immunohistochemistry are commonly used to detect the ALK fusion. Although FISH is currently the gold standard technique, there are no perfect methods for detecting these genetic alterations. In this article, we discuss the advantages and disadvantages of each method and the possible criteria for selecting patients who are more likely to have the ALK fusion. If we can successfully screen patients, then ALK inhibitor treatment will be the best example of personalized therapy in terms of selecting patients with an uncommon genotype from a larger group with the same tumor phenotype. In other words, the personalized therapy may offer a new challenge for current clinical oncology

EGFR T790M Mutation: A Double Role in Lung Cancer Cell Survival?

Abstract:Even though lung cancer patients harboring a mutation in the epidermal growth factor receptor (EGFR) gene exhibit an initial dramatic response to EGFR tyrosine kinase inhibitors (EGFR-TKIs), acquired resistance is almost inevitable after a progression-free period of approximately 10 months. A secondary point mutation that substitutes methionine for threonine at amino acid position 790 (T790M) is a molecular mechanism that produces a drug-resistant variant of the targeted kinase. The T790M mutation is present in about half of the lung cancer patients with acquired resistance, and reported to act by increasing the affinity of the receptor to adenosine triphosphate, relative to its affinity to TKIs. Nevertheless, several lines of evidence indicate that the T790M mutation confers growth advantage to cancer cells, and it was shown that mice expressing tetracycline-inducible EGFR transgenes harboring the T790M mutation develop lung tumors. Thus, T790M mutation seems to play a double role in the survival of lung cancer cells. Several second-generation EGFR-TKIs are currently being developed to overcome the acquired resistance caused by the T790M mutation. MET (met proto-oncogene) amplification or activation of IGF1R are reported as alternative mechanisms for acquired resistance to EGFR-TKIs. Clarification of the pathways leading to acquired resistance is essential to maximize the efficacy of EGFR-TKI therapy for patients with lung cancer

Plain language summary of the CheckMate 816 study results: nivolumab plus chemotherapy given before surgery for non–small-cell lung cancer

Immunotherapy; Neoadjuvant treatment; Presurgery treatmentImmunoteràpia; Tractament neoadjuvant; Tractament preoperatoriInmunoterapia; Tratamiento neoadyuvante; Tratamiento preoperatorioWhat is this summary about?: In this article, we summarize results from the ongoing phase 3 CheckMate 816 clinical study that were published in The New England Journal of Medicine in 2022. The goal of CheckMate 816 was to find out if nivolumab, an immunotherapy that activates a person's immune system (the body's natural defense system) to fight cancer, plus chemotherapy works better than chemotherapy alone when given before surgery in people with non-small-cell lung cancer (NSCLC) that can be removed surgically (resectable NSCLC). What happened in the study?: Adults who had not previously taken medications to treat NSCLC and whose cancer could be removed with surgery were included in CheckMate 816. During this study, a computer randomly assigned the treatment each person would receive before surgery for NSCLC. In total, 179 people were randomly assigned to receive nivolumab plus chemotherapy, and 179 people were randomly assigned to receive chemotherapy alone. The researchers assessed whether people who received nivolumab plus chemotherapy lived longer without the cancer geting worse or coming back and whether there were any cancer cells left in the tumor and lymph nodes removed by surgery. The researchers also assessed how adding nivolumab to chemotherapy affected the timing and outcomes of surgery and whether the combination of these drugs was safe. What were the results?: Researchers found that people who took nivolumab plus chemotherapy lived longer without the cancer getting worse or coming back compared with those who took chemotherapy alone. More people in the nivolumab plus chemotherapy group had no cancer cells left in the tumor and lymph nodes removed by surgery. Most people went on to have surgery in both treatment groups; the people who took nivolumab plus chemotherapy instead of chemotherapy alone had less extensive surgeries and were more likely to have good outcomes after less extensive surgeries. Adding nivolumab to chemotherapy did not lead to an increase in the rate of side effects compared with chemotherapy alone, and side effects were generally mild and manageable. What do the results of the study mean?: Results from CheckMate 816 support the benefit of using nivolumab plus chemotherapy before surgery for people with resectable NSCLC.The CheckMate 816 study was sponsored by Bristol Myers Squibb

Lung adenocarcinoma: Sustained subtyping with immunohistochemistry and EGFR, HER2 and KRAS mutational status

Pulmonary adenocarcinomas are still in the process of achieving morphological, immunohistochemical and genetic standardization. The ATS/ERS/IASLC proposed classification for lung adenocarcinomas supports the value of the identification of histological patterns, specifically in biopsies. Thirty pulmonary adenocarcinomas were subjected to immunohistochemical study (CK7, CK5, 6, 18, CK20, TTF1, CD56, HER2, EGFR and Ki-67), FISH and PCR followed by sequencing and fragment analysis for EGFR, HER2 and KRAS. Solid pattern showed lower TTF1 and higher Ki-67 expression. TTF1 expression was higher in non-mucinous lepidic and micropapillary patterns when compared to acinar and solid and acinar, solid and mucinous respectively. Higher Ki67 expression was present in lepidic and solid patterns compared to mucinous. EGFR membranous staining had increasing expression from non-mucinous lepidic/BA pattern to solid pattern and micropapillary until acinar pattern. EGFR mutations, mainly in exon 19, were more frequent in females, together with non-smoking status, while KRAS exon 2 mutations were statistically more frequent in males, especially in solid pattern. FISH EGFR copy was correlated gross, with mutations. HER2 copy number was raised in female tumours without mutations, in all cases. Although EGFR and KRAS mutations are generally considered mutually exclusive, in rare cases they can coexist as it happened in one of this series, and was represented in acinar pattern with rates of 42.9% and 17.9%, respectively. EGFR mutations were more frequent in lepidic/BA and acinar patterns. Some cases showed different EGFR mutations. The differences identified between the adenocarcinoma patterns reinforce the need to carefully identify the patterns present, with implications in diagnosis and in pathogenic understanding. EGFR and KRAS mutational status can be determined in biopsies representing bronchial pulmonary carcinomas because when a mutation is present it is generally present in all the histological patterns.info:eu-repo/semantics/publishedVersio

The Effect of Gefitinib on B-RAF Mutant Non-small Cell Lung Cancer and Transfectants

Abstract:We previously reported one patient with squamous cell carcinoma of the lung that showed the long-term effect to gefitinib with complete response. In the present report, we examine the epidermal growth factor receptor (EGFR) and K-RAS, HER2, and B-RAF mutations in this patient to find a B-RAF exon11 mutation, resulting in a substitution of valine by phenylalanine at codon 470 (V470F) as a novel type of B-RAF mutation in human cancers. In addition, the fluorescence in situ hybridization analysis for EGFR showed the high polysomy status. B-RAF is a nonreceptor serine/threonine kinase whose kinase domain has a structure similar to other protein kinases, including EGFR members. Of interest, the B-RAF V470F mutation corresponds to a position similar to the EGFR G719X mutation located on the phosphate binding (P)-loop of EGFR that clamps ATP into the catalytic cleft. This observation suggests that gefitinib may have an anti-cancer effect on B-RAF mutant tumors. Indeed, previous reports demonstrated that H1666 cells harboring B-RAF G465V mutations showed sensitivity to gefitinib, inhibiting phosphorylation of ERK1/2. We examined the effect of gefitinib on transient transfectants of the B-RAF mutant, but no drastic inhibition of ERK1/2 phosphorylation that was one of the downstream molecules of B-RAF was induced by gefitinib.In summary, we found a novel B-RAF V470F mutation in lung squamous cell carcinoma that showed response to gefitinib. However, our in vitro investigation did not explain the response observed in this particular patient. Further investigation is necessary to elucidate the mechanism of tumor sensitivity to EGFR tyrosine kinase inhibitors

Osimertinib in Patients with T790M-Positive Advanced Non-small Cell Lung Cancer: Korean Subgroup Analysis from Phase II Studies

Purpose Osimertinib is a third-generation, irreversible, oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) that potently and selectively inhibits both EGFR sensitizing mutation and EGFR T790M and has demonstrated efficacy in non-small cell lung cancer (NSCLC) central nervous system (CNS) metastases. We present results of a subgroup analysis of Korean patients from the pooled data of two global phase II trials: AURA extension (NCT01802632) and AURA2 (NCT02094261). Materials and Methods Enrolled patients had EGFR T790M-positive NSCLC and disease progression during or after EGFR-TKI therapy. Patients received osimertinib 80 mg orally once daily until disease progression. The primary endpoint was objective response rate (ORR). Results In total, 66 Korean patients received osimertinib treatment with a median treatment duration of 19 months. In the evaluable-for-response population (n=62), ORR was 74% (95% confidence interval [CI], 61.5 to 84.5) and median duration of response was 9.8 months (95% CI, 7.1 to 16.8). In the full analysis set (n=66), median progression-free survival was 10.9 months (95% CI, 8.3 to 15.0; data cutoff November 1, 2016), and median overall survival was 29.2 months (95% CI, 24.8 to 35.7; data cutoff May 1, 2018). Eight patients with CNS metastases were evaluable for response, none of whom showed CNS progression. The most common adverse events were rash (53%), cough (33%), paronychia, diarrhea, and decreased appetite (each 32%). Conclusion Efficacy and safety profiles of osimertinib in this subgroup are consistent with the global phase II pooled population, which supports osimertinib as a recommended treatment for Korean patients with T790M positive NSCLC.