Effectiveness of ALK inhibitors in treatment of CNS metastases in NSCLC patients

Roles of SPOCK1 in the Formation Mechanisms and Treatment of Non-Small-Cell Lung Cancer and Brain Metastases from Lung Cancer

Lung cancer is a malignant tumor with high morbidity and mortality in China and worldwide. Once it metastasizes to the brain, its prognosis is very poor. Brain metastases are found in about 20% of newly diagnosed non-small-cell lung cancer (NSCLC) patients. About 30% of NSCLC patients develop brain metastases during treatment. NSCLC that is positive for EGFR, ALK, and ROS1 variations is especially likely to metastasize to the brain. SPOCK1 is a proteoglycan with systemic physiological functions. It regulates the self-renewal of brain metastasis-initiating cells, regulates invasion and metastasis from the lung to the brain, plays an important role in tumor progression and treatment resistance, and has higher expression in metastatic tumor tissues than other tissues. Current treatments for NSCLC brain metastases include surgery, whole-brain radiotherapy, stereotactic radiotherapy, targeted therapy, and chemotherapy. SPOCK1 is involved in many signaling pathways, by which it influences a variety of NSCLC treatment methods. In this paper, the progress of research on the treatment of NSCLC brain metastases is reviewed to guide decisions on treatment options in clinical practice.

Recent developments in receptor tyrosine kinase inhibitors: A promising mainstay in targeted cancer therapy

During the past two decades, significant advances have been made in the discovery and development of targeted inhibitors aimed at improving the survival rates of cancer patients. Among the multitude of potential therapeutic targets identified thus far, Receptor Tyrosine Kinases (RTKs) are of particular importance. Dysregulation of RTKs has been implicated in numerous human diseases, particularly cancer, where aberrant signaling pathways contribute to disease progression. RTKs have a profound impact on intra and intercellular communication, and they also facilitate post-translational modifications, notably phosphorylation, which intricately regulates a multitude of cellular processes. Prolonged phosphorylation or the disruption of kinase regulation may lead to significant alterations in cell signaling. The emergence of small molecule kinase inhibitors has revolutionized cancer therapy by offering a targeted and strategic approach that surpasses the efficacy of traditional chemotherapeutic drugs. Over the last two decades, a plethora of targeted inhibitors have been identified or engineered and have undergone clinical evaluation to enhance the survival rates of cancer patients. In this review, we have compared the expression of different RTKs, including Met, KDR/VEGFR2, EGFR, BRAF, BCR, and ALK across different cancer types in TCGA samples. Additionally, we have summarized the recent development of small molecule inhibitors and their potential in treating various malignancies. Lastly, we have discussed the mechanisms of acquired therapeutic resistance with a focus on kinase inhibitors in EGFR mutant and ALK-rearranged non-small cell lung cancer and BCR-ABL positive chronic myeloid leukemia.

Clinical and Molecular Traits of a Novel SPECC1L-ALK Fusion in a Patient with Advanced Non-Small Cell Lung Cancer

Anaplastic lymphoma kinase (ALK) fusions account for 5-7% of non-small cell lung cancer (NSCLC) patients, the therapeutic approaches for which have significantly evolved in the last few years. However, the response to target therapies remains heterogeneous, partially due to the many different ALK fusion variants reported to date. Rare fusion variants have also been discovered, but their role in influencing responses to ALK inhibitors (ALKis) remains poorly elucidated. Laboratory investigation at both the tissue and protein levels, and a molecular profile by next-generation sequencing (NGS) were performed on a lung biopsy sample from one patient with poorly differentiated adenocarcinoma. An in silico prediction model using ColabFold software v1.5.5 was used to model and predict the entire structure of the chimeric aberrant ALK protein. Here, we report a case of a former smoker, a 60-year-old man, diagnosed with NSCLC and undergoing ALK translocation. He received first-, second- and third-generation ALK protein inhibitors (ALKis), showing a clinical benefit for about 4 years. IHC analysis and the molecular examination of the tissue biopsy indicated a positive staining for ALK and a novel ALK gene fusion variant, involving the sperm antigen with calponin homology and coiled-coil domain 1-like (SPECC1L) gene with an unreported breakpoint in exon 7. The novel SPECCL1::ALK fusion was identified using Anchored Multiplex PCR (AMP)-NGS technology and was predicted to retain the Pkinase_Tyr domain at the carboxy-terminal region of the resulting chimeric protein. To the best of our knowledge, this is the first case of an ALK-positive NSCLC patient carrying the SPECC1L exon 7 fusion breakpoint and one of the few reports about clinical outcomes related to SPECC1L::ALK fusion. The in silico hypothesized biological role of this newly identified fusion variant corroborates the observed clinical response to multiple ALKis. The molecular findings also reinforce the utility of AMP-based NGS technology as a valuable tool for the identification of rare chromosomal events that may be related to the variability of patient outcomes to different ALKis treatments.

Evaluation of Immunohistochemical Expression of ALK-1 in Gliomas, WHO Grade 4 and Its Correlation with IDH1-R132H Mutation Status

BACKGROUND

Glioblastoma (GB), a grade 4 glioma is the most common primary malignant brain tumor in adults. Recently, the mutation status of isocitrate dehydrogenase (IDH) has been crucial in the treatment of GB. IDH mutant cases display a more favorable prognosis than IDH-wild type ones. The anaplastic lymphoma kinase (ALK) is expressed as a receptor tyrosine kinase in both the developing central and peripheral nervous systems. Increasing lines of evidence suggest that ALK is over-expressed in GB and represents a potential therapeutic target.

OBJECTIVES

The goal of the current study was to investigate ALK-1 immunohistochemical expression in gliomas, grade 4, besides its correlation with IDH1-R132H mutation status and the clinicopathological parameters of the tumors.

MATERIAL AND METHODS

Seventy cases of gliomas, grade 4 were tested for immunohistochemical expression of ALK-1 & IDH1-R132H in the tumor cells.

RESULTS

ALK-1 immunoexpression was detected in 22.9% of our cases and IDH1-R132H mutation was detected in 12.9% of them. ALK-1 expression (100%) was only detected in the more aggressive IDH R132H-negative GBs. ALK-1 expression was also noted in the larger-sized tumors, more in males and patients older than the mean age.  Conclusion: Our results suggest that mutations in ALK-1 may predict a more dismal prognosis since ALK expression was only noted in IDH-R132H negative GBs known to have a considerably poorer outcome compared to IDH-R132H mutant cases. GBs with detectable ALK-protein expression could potentially experience substantial clinical advantages through the utilization of newly introduced ALK inhibitors allowing personalized treatment to a subset of patients. Hence, future studies targeting ALK in IDH wildtype Glioblastomas including clinical trials on larger scales are recommended.

Sustained Improvement in the Management of Patients with Non-Small-Cell Lung Cancer (NSCLC) Harboring ALK Translocation: Where Are We Running?

ALK translocation amounts to around 3-7% of all NSCLCs. The clinical features of ALK+ NSCLC are an adenocarcinoma histology, younger age, limited smoking history, and brain metastases. The activity of chemotherapy and immunotherapy is modest in ALK+ disease. Several randomized trials have proven that ALK inhibitors (ALK-Is) have greater efficacy with respect to platinum-based chemotherapy and that second/third generation ALK-Is are better than crizotinib in terms of improvements in median progression-free survival and brain metastases management. Unfortunately, most patients develop acquired resistance to ALK-Is that is mediated by on- and off-target mechanisms. Translational and clinical research are continuing to develop new drugs and/or combinations in order to raise the bar and further improve the results attained up to now. This review summarizes first-line randomized clinical trials of several ALK-Is and the management of brain metastases with a focus on ALK-I resistance mechanisms. The last section addresses future developments and challenges.