The RET fusion gene and its correlation with demographic and clinicopathological features of non-small cell lung cancer: a meta-analysis

Impact of demographics and social vulnerability on outcomes in pediatric medullary thyroid cancer

OBJECTIVE

To evaluate the impact of social vulnerability and social determinants of health on outcomes in pediatric medullary thyroid cancer.

METHODS

A SEER database review looking at cases of pediatric medullary thyroid cancer from 1975 to 2016 was conducted and analyzed including data from the American Community Survey.

RESULTS

A total of 174 patients were included in analysis. Five-year overall survival was 97.7 % and the disease specific survival (DSS) was 98.3 %. On univariate analysis, male sex was associated with worsened overall survival (HR = 4.2, CI 1.1-15.5, p < 0.05) but did not reach statistical significance on multivariate analysis. Asian or Pacific Islander race was associated with worsened overall survival on both univariate and multivariate analysis (HR = 5.5, CI 1.4-22.2, p < 0.05). Presenting with localized disease without nodal or distant metastasis was found to be a protective factor (HR = 0.2, CI 0.05-0.53, p < 0.01).

CONCLUSION

Asian American/Pacific Islander patients and male patients may have poorer survival in pediatric medullary thyroid cancer. More research should be completed to better understand underlying factors.

Diagnosis, Treatment Patterns, and Outcomes in Real-World Patients with RET Fusion-Positive Non-small Cell Lung Cancer in China

INTRODUCTION

Epidemiological studies on non-small cell lung cancer (NSCLC) have noted RET fusions as an oncogenic driver. However, real-world data on RET biomarker testing and treatment patterns in China remain limited. This study aimed to examine demographics, clinical and molecular features, and RET testing and treatment patterns and outcomes in patients with RET fusion-positive NSCLC.

METHODS

Utilizing real-world data from the Chinese Multi-center Lung Cancer Precision Medicine Registry, this retrospective cohort study focused on Chinese patients diagnosed with RET fusion-positive NSCLC between January 1, 2016, and November 30, 2021. The cohort was divided into early-stage and advanced-stage subgroups. Demographics, clinical and molecular profiles, treatment received, and outcomes including real-world event free survival (rwEFS), real-world progression free survival (rwPFS), and overall survival (OS) were assessed.

RESULTS

The study included 121 patients with RET fusion-positive NSCLC, comprising 80 early-stage and 58 advanced-stage patients. High biomarker testing rates were observed at diagnosis (75% for early-stage, 78% for advanced-stage). RET testing was often conducted via tissue samples (95.9%) and next-generation sequencing (89.3%). KIF5B (57.0%) and CCDC6 (20.7%) were the most common gene fusion partners. The most frequent oncogenic mutations were TP53 (15.7%) and EGFR (6.6%). Platinum-based chemotherapy was the most common first-line treatment among advanced-stage patients. Median rwPFS was 9.22 months for advanced-stage patients on first-line chemotherapy, and median OS was 30.7 months for all advanced-stage patients. The 2-year rwEFS rate for early-stage patients was 86.0%, with a median OS of 91.9 months.

CONCLUSIONS

The study observed high biomarker testing rates at initial diagnosis for early- and advanced-stage RET fusion-positive NSCLC patients in China. The heterogeneous treatment pattern of advanced patients suggests the need for more precise, evidence-based treatment to guide clinical decisions. Given the existing therapeutic regimens fall short of adequately addressing treatment needs, targeted therapies are essential to improve outcomes.

Combining demographic data and transvaginal ultrasonography: a predictive model for endometrial carcinoma in postmenopausal patients

BACKGROUND

Although clinical guidelines exist for diagnosing abnormal uterine bleeding, there is a significant lack of agreement on the best management strategies for women presenting with symptom, particularly in diagnosing endometrial cancer. This study aimed to develop a preoperative risk model that utilizes demographic factors and transvaginal ultrasonography of the endometrium to assess and predict the risk of malignancy in females with endometrial cancer.

METHODS

In this retrospective study, a logistic regression model was developed to predict endometrial carcinoma using data from 356 postmenopausal women with endometrial lesions and an endometrial thickness (ET) of 5 mm or more. These patients had undergone transvaginal ultrasonography prior to surgery, with findings including 247 benign and 109 malignant cases. The model's predictive performance was evaluated using receiver operating characteristic (ROC) curve analysis and compared with post-surgical pathological diagnoses.

RESULTS

Our model incorporates several predictors for endometrial carcinoma, including age, history of hypertension, history of diabetes, body mass index (BMI), duration of vaginal bleeding, endometrial thickness, completeness of the endometrial line, and endometrial vascularization. It demonstrated a strong prediction with an area under the curve (AUC) of 0.905 (95% CI, 0.865-0.945). At the optimal risk threshold of 0.33, the model achieved a sensitivity of 82.18% and a specificity of 92.80%.

CONCLUSIONS

The established model, which integrates ultrasound evaluations with demographic data, provides a specific and sensitive method for assessing and predicting endometrial carcinoma.

First-line selpercatinib for a patient with RET fusion-positive pulmonary large cell neuroendocrine carcinoma

Pulmonary large cell neuroendocrine carcinoma (LCNEC) is an uncommon variant of non-small cell lung cancer (NSCLC), known for its aggressive behavior. This includes rapid progression, widespread metastases, and resistance to conventional chemotherapy, all of which contribute to a dismal prognosis. Consequently, managing pulmonary LCNEC remains a significant challenge. In this case report, we describe the successful use of selpercatinib, RET (rearranged during transfection) kinase inhibitor, as a first-line treatment in a patient with advanced pulmonary LCNEC harboring a RET fusion gene. Although RET fusion genes are exceedingly rare in pulmonary LCNEC, this case underscores the importance of early genetic testing in patients with pulmonary LCNEC to tailor targeted therapies effectively.

Molecular Landscape and Therapeutic Strategies against Colorectal Cancer

Colorectal cancer (CRC) is the second leading cause of cancer deaths worldwide. Although the overall incidence of CRC is decreasing, the incidence of young-onset CRC, characterized by a diagnosis of CRC before age 50, is increasing. Outcomes for CRC patients are improving, partly due to comprehensive molecular characterization of tumors and novel therapeutic strategies. Advances in genomic and transcriptomic analyses using blood- and tumor-tissue-based sequencing have facilitated identification of distinct tumor subtypes harboring unique biological characteristics and therapeutic vulnerabilities. These insights have led to the development and incorporation of targeted therapies and immunotherapy in CRC treatment. In this review, we discuss the molecular landscape and key oncogenes/tumor suppressors contributing to CRC tumorigenesis, metastasis, and therapeutic resistance. We also discuss personalized therapeutic strategies for subsets of CRC patients and provide an overview of evolving novel treatments being evaluated in clinical trials.

Targeting RET alterations in non-small cell lung cancer

Rearranged during transfection (RET) alterations, which lead to aberrant activation of the RET proto-oncogene, have been identified in various cancers. In non-small cell lung cancer (NSCLC), RET mutations often manifest as RET fusion genes and are observed in 1-2 % of patients with NSCLC. In recent years, selective RET inhibitors such as selpercatinib and pralsetinib, approved by the Food and Drug Administration (FDA) in 2020, have been part of the revolutionary changes in the treatment landscape for non-small cell lung cancer. While first-generation RET inhibitors have become part of the standard of care for RET-fusion positive NSCLC, a new challenge has emerged: acquired resistance to RET inhibitors. RET resistance is a complex phenomenon that can manifest as either on-target or off-target resistance. Numerous studies have been conducted to identify the mechanisms behind this resistance. This review provides an overview of the biology of RET in NSCLC, methods of RET testing, and a comprehensive analysis of the clinical outcomes associated with multikinase and selective RET inhibitors for NSCLC. Additionally, we will explore future perspectives for RET fusion-positive NSCLC, including ongoing trials and the challenges involved in overcoming resistance to RET inhibitors.

Lung cancer in patients who have never smoked - an emerging disease

Lung cancer is the most common cause of cancer-related deaths globally. Although smoking-related lung cancers continue to account for the majority of diagnoses, smoking rates have been decreasing for several decades. Lung cancer in individuals who have never smoked (LCINS) is estimated to be the fifth most common cause of cancer-related deaths worldwide in 2023, preferentially occurring in women and Asian populations. As smoking rates continue to decline, understanding the aetiology and features of this disease, which necessitate unique diagnostic and treatment paradigms, will be imperative. New data have provided important insights into the molecular and genomic characteristics of LCINS, which are distinct from those of smoking-associated lung cancers and directly affect treatment decisions and outcomes. Herein, we review the emerging data regarding the aetiology and features of LCINS, particularly the genetic and environmental underpinnings of this disease as well as their implications for treatment. In addition, we outline the unique diagnostic and therapeutic paradigms of LCINS and discuss future directions in identifying individuals at high risk of this disease for potential screening efforts.

Molecular pathology of non-small cell carcinoma

Currently, lung cancer is treated by the highest number of therapeutic options and the benefits are based on multiple large-scale sequencing studies, translational research and new drug development, which has promoted our understanding of the molecular pathology of lung cancer. According to the driver alterations, different characteristics have been revealed, such as differences in ethnic prevalence, median age and alteration patterns. Consequently, beyond traditional chemoradiotherapy, molecular-targeted therapy and treatment with immune check-point inhibitors (ICI) also became available major therapeutic options. Interestingly, clinical results suggest that the recently established therapies target distinct lung cancer proportions, particularly between the EGFR/ALK and PD-1/PD-L1-positive subsets, e.g. the kinase inhibitors target driver mutation-positive tumours, whereas driver mutation-negative tumours respond to ICI treatment. These therapeutic efficacy-related differences might be explained by the molecular pathogenesis of lung cancer. Addictive driver mutations promote tumour formation with powerful transformation performance, resulting in a low tumour mutation burden, reduced immune surveillance, and subsequent poor response to ICIs. In contrast, regular tobacco smoke exposure repeatedly injures the proximal airway epithelium, leading to accumulated genetic alterations. In the latter pathway, overgrowth due to alteration and immunological exclusion against neoantigens is initially balanced. However, tumours could be generated from certain clones that outcompete immunological exclusion and outgrow the others. Consequently, this cancer type responds to immune check-point treatment. These pathogenic differences are explained well by the two-compartment model, focusing upon the anatomical and functional composition of distinct cellular components between the terminal respiratory unit and the air-conducting system.

Management of Advanced Medullary Thyroid Carcinoma: Current Systemic Therapy Options

The current rapid development of more selective and effective drugs for the treatment of thyroid cancer has open a new era in the treatment of patients with this condition, in the past limited to the possibility of only radioactive iodine for well differentiated tumor and surgery for medullary thyroid carcinoma (MTC). The treatment of advanced medullary thyroid carcinoma has evolved in the last few years and options for patients with advanced disease are now available. Multikinase inhibitors (MKIs) with nonselective RET inhibition like Vandetanib and Cabozantinib were approved for the treatment of MTC, although the efficacy is limited due to the lack of specificity resulting in a higher rate of drug-related adverse events, leading to subsequent dose reductions, or discontinuation, and the development of a resistance mechanism like seen on the RET Val804 gatekeeper mutations. MTC is associated with mutations in the RET protooncogene, and new highly selective RET inhibitors have been developed including Selpercatinib and Pralsetinib, drugs that have demonstrate excellent results in clinical trials, and efficacy even in the presence of gatekeeper mutations. However, despite their efficacy and great tolerability, mechanisms of resistance have been described, such as the RET solvent front mutations. Due to this, the need of constant evolution and drug research is necessary to overcome the emergence of resistance mechanisms.

Efficacy and safety of pralsetinib in patients with advanced RET fusion-positive non-small cell lung cancer

BACKGROUND

Pralsetinib is a potent, selective RET inhibitor targeting oncogenic RET alterations. As part of the global, phase 1/2 ARROW trial (NCT03037385), the efficacy and safety of pralsetinib in Chinese patients with advanced RET fusion-positive non-small cell lung cancer (NSCLC) were evaluated.

METHODS

Adult patients with advanced, RET fusion-positive NSCLC with or without prior platinum-based chemotherapy were enrolled into two cohorts receiving 400-mg once-daily oral pralsetinib. Primary end points were objective response rates assessed by blinded independent central review and safety.

RESULTS

Of 68 patients enrolled, 37 had received prior platinum-based chemotherapy (48.6% with ≥3 prior systemic regimens) and 31 were treatment-naïve. As of March 4, 2022 (data cutoff), of the patients with measurable lesions at baseline, a confirmed objective response was observed in 22 (66.7%; 95% confidence interval [CI], 48.2-82.0) of 33 pretreated patients, including 1 (3.0%) complete response and 21 (63.6%) partial responses; and in 25 (83.3%; 95% CI, 65.3-94.4) of 30 treatment-naïve patients, including two (6.7%) complete responses and 23 (76.7%) partial responses. Median progression-free survival was 11.7 months (95% CI, 8.7-not estimable) in pretreated patients and 12.7 months (95% CI, 8.9-not estimable) in treatment-naïve patients. The most common grade 3/4 treatment-related adverse events in 68 patients were anemia (35.3%) and decreased neutrophil count (33.8%). Eight (11.8%) patients discontinued pralsetinib because of treatment-related adverse events.

CONCLUSION

Pralsetinib showed robust and durable clinical activity with a well-tolerated safety profile in Chinese patients with RET fusion-positive NSCLC.

CLINICAL TRIAL REGISTRATION

NCT03037385.

Selpercatinib monotherapy in a Chinese patient with RET fusion/ EGFR co-mutated nonsmall cell lung cancer from the Phase II LIBRETTO-321 study: a case report

Rearranged during transfection ( RET ) fusions and epidermal growth factor receptor ( EGFR ) mutations are potent oncogenic drivers in patients with nonsmall cell lung cancer (NSCLC), but rarely co-exist. Concurrent RET/EGFR mutations have been reported in patients with NSCLC who develop resistance to EGFR tyrosine kinase inhibitors but are even less frequent in treatment-naïve patients. Consequently, there is no standard treatment for RET/EGFR -mutated NSCLC. We report a case of RET/EGFR mutant NSCLC successfully treated with the oral, potent, highly selective RET inhibitor selpercatinib (160 mg daily for 28-day cycles) in an ongoing phase II study in Chinese patients with NSCLC (LIBRETTO-321). The patient, a female nonsmoker, was diagnosed with de-novo left lung adenocarcinoma with neuroendocrine differentiation, and a RET fusion was detected by next-generation sequencing testing. The patient had two tumors in the pleura, a third in the subcarinal lymph node, and a nontarget tumor in the pleura. Pleural biopsy analysis confirmed a RET fusion KIF5B (K15;R12) and an EGFR exon 19 deletion. The patient achieved a partial response (PR) with selpercatinib (absence of target tumors in pleura and reduction in the size of lymph node tumor). The PR persisted for 14.7 months, with disease progression in the nontarget lesion in the pleura and a new lesion in the liver (the PR had persisted), resulting in the discontinuation of selpercatinib. The only notable adverse event was grade 3 elevated transaminase, that was effectively managed by dose reduction. These data may support the use of selpercatinib in patients with RET/EGFR co-mutated NSCLC.

Targeted treatments after chemoradiotherapy failure in a patient with relapsed, advanced non‑small cell lung cancer with on‑therapy circulating tumor biomarker monitoring: A case report

Ongoing investigations of targeted therapeutic agents and their increased clinical applications, together with research in genomics and proteomics, have explored a variety of novel approaches for treatment of lung cancer, and 'molecular subtypes' have been defined based on specific actionable genetic aberrations. Liquid biopsies, including circulating tumor DNA (ctDNA) testing, are of value for cancer diagnosis and comprehensive genomic profiling, such as the identification of cancer subtypes and major genetic alterations in cancer cells. The case of a 66-year-old male patient with newly-diagnosed driver mutation-negative advanced non-small cell lung cancer (NSCLC) who underwent conventional therapy is described in the present report. The patient underwent regular monitoring, including continuous ctDNA analysis, imaging and assessment of tumor marker levels such as carcinoembryonic antigen (CEA). The patient initially presented with deep vein thrombosis which affected both lower extremities and without any symptoms in the lung, with a positron emission tomography scan identifying irregular pulmonary nodules in the right lower lobe and enlarged right supraclavicular lymph nodes. Subsequent ultrasound-guided fine-needle aspiration with nodule biopsy indicated advanced unresectable disease at stage IIIB based on the Tumor-Node-Metastasis staging system by the American Joint Committee on Cancer. Next-generation sequencing of tumor tissue and peripheral blood confirmed driver mutation-negative genes, including epidermal growth factor receptor, rat sarcoma, ALK receptor tyrosine kinase, ROS1 proto-oncogene receptor tyrosine kinase and rearrangement during transfection (RET). After 5 years of chemoradiotherapy and surveillance of ctDNA and CEA levels, detectable kinesin family member 5B (KIF5B)-RET fusion in ctDNA and rising CEA levels prompted early scans, which identified disease progression. The patient subsequently received the oral RET inhibitor pralsetinib, with treatment being currently ongoing for ≥17 months without detectable KIF5B-RET ctDNA or elevated CEA levels, with an ongoing minor response and stable disease based on Response Evaluation Criteria in Solid Tumors v1.1 on imaging. The present case illustrates the potential role of on-therapy circulating tumor biomarker monitoring as a non-traumatic method to evaluate therapy response and detect early disease progression in patients with advanced NSCLC. Integration of circulating tumor biomarker testing into the management of patients with advanced NSCLC requires additional prospective studies to actively assess and elucidate optimal treatment strategies.

Pathological characteristics and tumour immune microenvironment of lung malignancies with RET rearrangement

BACKGROUND

For patients with lung malignancies with RET rearrangement, the efficacy of immune checkpoint inhibitors is limited. The characteristics of the tumour immune microenvironment (TIME) and molecular pathological features of these patients have not been well elucidated. We aimed to investigate their clinical outcomes and explore characteristics of TIME, using multiplex immunohistochemistry technology (mIHC).

PATIENTS AND METHODS

The pathology and TIME characteristics of 29 patients with lung malignancies with RET rearrangement were retrospectively analysed, and their relationships with clinical efficacy and prognosis were investigated. Gene detection relied on high-throughput sequencing, and TIME detection was based on mIHC.

RESULTS

Of 29 patients, 25(86%) had adenocarcinoma, and the acinar type accounted for the greatest percentage of patients, followed by the solid type, regardless of whether the disease was early or locally advanced and metastatic. In addition, we report a novel KIF5B-RET(k24:R8) rearrangement in pulmonary sarcoma. The density of CD8+ T cells in tumour stroma in early-stage patients was significantly higher than that in locally advanced and metastatic patients (P = 0.014). The proportion of M2 macrophages in tumour stroma was significantly higher than that in tumour parenchyma (P = 0.046). Although the difference was not statistically significant (P = 0.098), patients positive for M2 macrophage infiltration into the tumour parenchyma (≥5%) may have a better prognosis. Seven patients received immunotherapy and disease control rate was 85.7%.

CONCLUSIONS

A novel KIF5B-RET rearrangement variant in pulmonary sarcoma shows similar TIME characteristics to lung cancer. amongst patients with lung malignancies with RET rearrangement, patients with M2 macrophage infiltration into the tumour parenchyma may have a better prognosis, but further studies with larger cohorts are needed.

Targeted therapy in lung cancer: Are we closing the gap in years of life lost?

PURPOSE

Patients with non-small cell lung cancer (NSCLC) that harbor driver mutations are associated with a cancer diagnosis at a younger age. While targeted therapies provide deep remissions and durable benefit in a subset of patients, it is unclear whether targeted therapies bridge the gap in years of life lost (YLL) in these younger NSCLC patients with targetable mutations in comparison to generally older NSCLC patients without actionable driver mutations.

MATERIALS AND METHODS

Retrospective cross-sectional study using landmark trials leading to the approval of targeted therapies in NSCLC with actionable mutations. We evaluated all targeted therapies as well as chemotherapy and IO regimens for the treatment of NSCLC through FDA Oncology Announcements and NCCN Guidelines for NSCLC (version 4.2021).

RESULTS

We estimated the YLL for each driver mutation, cumulative median duration of response (DOR) with targeted therapies by mutation type, and percentage of estimated improvement in YLL from NSCLC targeted therapies. The median ages at diagnosis (in years) for patients whose tumors express targetable mutations were: 47.6 (NTRK); 52.0 (ALK); 62.0 (HER2); 57.0 (ROS1); 61.4 (RET); 63.0 (BRAF); 69.0 (EGFR); and 72.0 (MET). For comparison, the median age at diagnosis for patients without driver mutations, regardless of PD-L1 status was 71 years. The median DOR (in years) for patients whose tumors express the same mutations include: 0.9 (NTRK); 3.9 (ALK); 0.6 (HER2); 6.2 (ROS1); 2.2 (RET); 1.5 (BRAF); 3.1 (EGFR); and 2.4 (MET). The median DOR for patients without driver mutations was 1.2 years. The cumulative estimated survival time (years; median age at diagnosis plus the median DOR or OS) for patients whose tumors express targetable mutations were: 48.5 (NTRK); 55.9 (ALK); 62.6 (HER2); 63.2 (ROS1); 63.6 (RET); 64.5 (BRAF); 72.1 (EGFR); and 74.4 (MET). The cumulative estimated survival time for patients without driver mutations, regardless of PD-L1 status, was 72.2 years of age. We calculated the number of years NSCLC is diagnosed earlier in patients with targetable mutations as follows: 23.4 (NTRK), 19 (ALK), 14 (ROS1), 11 (EGFR), 9.6 (RET), 9 (HER2), and 8 (BRAF). The percent difference (%) ameliorated in YLL by mutation type is as follows: 44.3 (ROS1), 28.2 (EGFR), 22.9 (RET), 20.5 (ALK), 18.8 (BRAF), 6.4 (HER2), and 3.7 (NTRK).

CONCLUSION

Although targeted therapies have paved the way for significant progress toward providing a survival benefit to many young patients with advanced NSCLC with actionable mutations, it is evident that these therapies still leave a wide gap in the YLL in these younger patients compared to generally older individuals with advanced NSCLC without targetable mutations.

Identification and Validation of Prognostic Markers for Lung Squamous Cell Carcinoma Associated with Chronic Obstructive Pulmonary Disease

Background

Globally, the incidence and associated mortality of chronic obstructive pulmonary disease (COPD) and lung carcinoma are showing a worsening trend. There is increasing evidence that COPD is an independent risk factor for the occurrence and progression of lung carcinoma. This study aimed to identify and validate the gene signatures associated with COPD, which may serve as potential new biomarkers for the prediction of prognosis in patients with lung carcinoma.

Methods

A total of 111 COPD patient samples and 40 control samples were obtained from the GSE76925 cohort, and a total of 4933 genes were included in the study. The weighted gene coexpression network analysis (WGCNA) was performed to identify the modular genes that were significantly associated with COPD. The KEGG pathway and GO functional enrichment analyses were also performed. The RNAseq and clinicopathological data of 490 lung squamous cell carcinoma patients were obtained from the TCGA database. Further, univariate Cox regression and Lasso analyses were performed to screen for marker genes and construct a survival analysis model. Finally, the Human Protein Atlas (HPA) database was used to assess the gene expression in normal and tumor tissues of the lungs.

Results

A 6-gene signature (DVL1, MRPL4, NRTN, NSUN3, RPH3A, and SNX32) was identified based on the Cox proportional risk analysis to construct the prognostic RiskScore survival model associated with COPD. Kaplan–Meier survival analysis indicated that the model could significantly differentiate between the prognoses of patients with lung carcinoma, wherein higher RiskScore samples were associated with a worse prognosis. Additionally, the model had a good predictive performance and reliability, as indicated by a high AUC, and these were validated in both internal and external sets. The 6-gene signature had a good predictive ability across clinical signs and could be considered an independent factor of prognostic risk. Finally, the protein expressions of the six genes were analyzed based on the HPA database. The expressions of DVL1, MRPL4, and NSUN3 were relatively higher, while that of RPH3A was relatively lower in the tumor tissues. The expression of SNX32 was high in both the tumor and paracarcinoma tissues. Results of the analyses using TCGA and GSE31446 databases were consistent with the expressions reported in the HPA database.

Conclusion

Novel COPD-associated gene markers for lung carcinoma were identified and validated in this study. The genes may be considered potential biomarkers to evaluate the prognostic risk of patients with lung carcinoma. Furthermore, some of these genes may have implications as new therapeutic targets and can be used to guide clinical applications.

NSCLC as the Paradigm of Precision Medicine at Its Finest: The Rise of New Druggable Molecular Targets for Advanced Disease

Standard treatment for advanced non-small cell lung cancer (NSCLC) historically consisted of systemic cytotoxic chemotherapy until the early 2000s, when precision medicine led to a revolutionary change in the therapeutic scenario. The identification of oncogenic driver mutations in EGFR, ALK and ROS1 rearrangements identified a subset of patients who largely benefit from targeted agents. However, since the proportion of patients with druggable alterations represents a minority, the discovery of new potential driver mutations is still an urgent clinical need. We provide a comprehensive review of the emerging molecular targets in NSCLC and their applications in the advanced setting.

Pralsetinib (Gavreto): Treatment of metastatic non-small-cell lung cancer in patients positive for RET fusions

DISCLAIMER

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

To review the pharmacology, efficacy, safety, dosing and administration, and place in therapy of pralsetinib, a tyrosine kinase inhibitor, for the treatment of non-small-cell lung cancer (NSCLC) in patients with RET fusions.

SUMMARY

RET fusion-positive NSCLC is a rare cancer caused by chromosomal rearrangements that lead to fusions of the RET gene with other genes, such as KIF5B and CCDC6. Until recently, patients were treated with platinum-based chemotherapy or multitargeted tyrosine kinase inhibitors. However, because of their nonspecific mechanism of action, these drugs did not have high response rates. In September 2020, the Food and Drug Administration approved pralsetinib (Gavreto), the first once-daily oral tyrosine kinase inhibitor, for patients with metastatic RET fusion-positive NSCLC. Pralsetinib has been demonstrated to have response rates of 57% and 70% in patients who were previously treated with platinum chemotherapy and patients who were treatment naive, respectively. Clinicians using pralsetinib should monitor for liver-related adverse events, hypertension, myelosuppression, pyrexia, sepsis, gastrointestinal symptoms, dyspnea, pneumonitis, and pneumonia, as these may require treatment interruption, dose reduction, or treatment discontinuation.

CONCLUSION

Pralsetinib is a unique targeted tyrosine kinase inhibitor approved for the treatment of patients with RET fusion-positive NSCLC who may desire a once-daily regimen. The recent approval of pralsetinib represents an important addition for the treatment of patients with RET fusion-positive NSCLC.

Immunotherapy in Non-Small Cell Lung Cancer With Actionable Mutations Other Than EGFR

While first line targeted therapies are the current standard of care treatment for non-small cell lung cancer (NSCLC) with actionable mutations, the cancer cells inevitably acquire resistance to these agents over time. Immune check-point inhibitors (ICIs) have improved the outcomes of metastatic NSCLC, however, its efficacy in those with targetable drivers is largely unknown. In this manuscript, we reviewed the published data on ICI therapies in NSCLC with ALK, ROS1, BRAF, c-MET, RET, NTRK, KRAS, and HER2 (ERBB2) alterations. We found that the objective response rates (ORRs) associated with ICI treatments in lung cancers harboring the BRAF (0-54%), c-MET (12-49%), and KRAS (18.7-66.7%) alterations were comparable to non-mutant NSCLC, whereas the ORRs in RET fusion NSCLC (less than10% in all studies but one) and ALK fusion NSCLC (0%) were relatively low. The ORRs reported in small numbers of patients and studies of ROS1 fusion, NTRK fusion, and HER 2 mutant NSCLC were 0-17%, 50% and 7-23%, respectively, making the efficacy of ICIs in these groups of patients less clear. In most studies, no significant correlation between treatment outcome and PD-L1 expression or tumor mutation burden (TMB) was identified, and how to select patients with NSCLC harboring actionable mutations who will likely benefit from ICI treatment remains unknown.

A contemporary review of rearranged during transfection-selective inhibitors

OBJECTIVE

Rearranged during transfection genes are present in 1-2% of patients who have non-small cell lung cancer and 10-30% of patients with papillary thyroid cancer. The objective of this article is to review the current rearranged during transfection inhibitors indicated for patients with rearranged during transfection-mutated cancers and their future directions.Data sources: The pivotal phase I/II studies for selpercatinib and pralsetinib were evaluated. Current studies on rearranged during transfection inhibitors were searched on ClinicalTrials.gov using the key word "RET."Data summary: Selpercatinib and pralsetinib were the first two U.S. Food and Drug Administration-approved rearranged during transfection-selective inhibitors for advanced or metastatic rearranged during transfection fusion-positive non-small cell lung cancer, rearranged during transfection-mutant medullary thyroid cancer, and rearranged during transfection fusion-positive thyroid cancer. Both agents showed promising efficacy with objective response rate ranging from 60% to 73% in all aforementioned rearranged during transfection-mutated cancers. Additionally, benefits were seen even in patients with intracranial metastasis at baseline. Both showed favorable safety profiles. Some common class adverse events included elevated liver function tests and hypertension. Hematologic side effects such as anemia and neutropenia were more common with pralsetinib. Selpercatinib had interactions with acid suppressive therapy and specific instructions when used concomitantly.

CONCLUSIONS

While the rearranged during transfection inhibitors are generally well-tolerated, each agent possesses slightly different efficacy, side-effect profile, and drug-drug interactions.

Glial-derived neurotrophic factor in human airway smooth muscle

Airway smooth muscle (ASM) cells modulate the local airway milieu via production of inflammatory mediators and growth factors including classical neurotrophins, such as brain-derived neurotrophic factor (BDNF). The glial cell-derived neurotrophic factor (GDNF) family of ligands (GFLs) are nonclassical neurotrophins and their role in the airway is barely understood. The major GFLs, GDNF and Neurturin (NRTN) bind to GDNF family receptor (GFR) α1 and α2 respectively that pair with Ret receptor to accomplish signaling. In this study, we found GDNF is expressed in human lung and increased in adult asthma, while human ASM expresses GDNF and its receptors. Accordingly, we used human ASM cells to test the hypothesis that ASM expression and autocrine signaling by GFLs regulate [Ca²⁺ ]_i . Serum-deprived ASM cells from non-asthmatics were exposed to 10 ng/ml GDNF or NRTN for 15 min (acute) or 24 h (chronic). In fura-2 loaded cells, acute GDNF or NRTN alone induced [Ca²⁺ ]_i responses, and further enhanced responses to 1 µM ACh or 10 µM histamine. Ret inhibitor (SPP86; 10 µM) or specific GDNF chelator GFRα1-Fc (1 µg/ml) showed roles of these receptors in GDNF effects. In contrast, NRTN did not enhance [Ca²⁺ ]_i response to histamine. Furthermore, conditioned media of nonasthmatic and asthmatic ASM cells showed GDNF secretion. SPP86, Ret inhibitor and GFRα1-Fc chelator markedly decreased [Ca²⁺ ]_i response compared with vehicle, highlighting autocrine effects of secreted GDNF. Chronic GDNF treatment increased histamine-induced myosin light chain phosphorylation. These novel data demonstrate GFLs particularly GDNF/GFRα1 influence ASM [Ca²⁺ ]_i and raise the possibility that GFLs are potential targets of airway hyperresponsiveness.

Tyrosine Kinase Inhibitors, Antibody-Drug Conjugates, and Proteolysis-Targeting Chimeras: The Pharmacology of Cutting-Edge Lung Cancer Therapies

The number of therapeutic options available for patients with advanced non-small-cell lung cancer has been led by deeper understanding of molecular drivers, immune function, and fundamental biology. In this article, we describe the relevant clinical pharmacologic characteristics of three broad classes of existing and investigational treatments, with a focus on mechanisms of action, adverse event profiles, pharmacokinetic and pharmacodynamic properties, and known and predicted resistance pathways. Specifically, within the kinase inhibitor class, agents directed against the RET, MET, and KRAS pathways are reviewed. Additionally, the first antibody-drug conjugates that target HER2 and HER3 are in trials and will ideally be available for patients soon. Finally, proteolysis-targeting chimeras approach pathway inhibition through enzyme degradation rather than target inhibition and are a promising platform for new agents in non-small-cell lung cancer and across cancer types. Each of these classes requires knowledge of clinical pharmacologic principles in development and use to ensure patient care in clinics and trials is optimized and personalized, including dosing and scheduling strategies, potential drug interactions, use in special populations, and monitoring parameters. Ideally, oncologists will continue to have new agents available across the non-small-cell lung cancer treatment spectrum to offer to a patient group that, until relatively recently, had few options.

Neurotrophin Regulation and Signaling in Airway Smooth Muscle

Structural and functional aspects of bronchial airways are key throughout life and play critical roles in diseases such as asthma. Asthma involves functional changes such as airway irritability and hyperreactivity, as well as structural changes such as enhanced cellular proliferation of airway smooth muscle (ASM), epithelium, and fibroblasts, and altered extracellular matrix (ECM) and fibrosis, all modulated by factors such as inflammation. There is now increasing recognition that disease maintenance following initial triggers involves a prominent role for resident nonimmune airway cells that secrete growth factors with pleiotropic autocrine and paracrine effects. The family of neurotrophins may be particularly relevant in this regard. Long recognized in the nervous system, classical neurotrophins such as brain-derived neurotrophic factor (BDNF) and nonclassical ligands such as glial-derived neurotrophic factor (GDNF) are now known to be expressed and functional in non-neuronal systems including lung. However, the sources, targets, regulation, and downstream effects are still under investigation. In this chapter, we discuss current state of knowledge and future directions regarding BDNF and GDNF in airway physiology and on pathophysiological contributions in asthma.

The clinical significance of RET gene fusion among Chinese patients with lung cancer

Background

The incidence of lung cancer is growing fast in China, however, the prognosis remains dismal due to the limited therapeutic approaches. The “ret proto-oncogene mutation” (RET) fusions have been proven to be the driver gene in lung cancer development and the therapeutic target of several multi-target tyrosine kinase inhibitors.

Methods

We applied formalin-fixed, paraffin-embedded (FFPE) samples of 39 patients with non-small cell lung cancer (NSCLC) using the Lung Plasma panel covering 168 cancer-associated genes and performed capture-based targeted deep sequencing to identify the RET fusion partners and concurrent gene mutation with Miseq. The log-rank test was used to compare the survival difference of patients according to treatment strategies. Statistical analyses and graphs were performed using R language and GraphPad Prism.

Results

Most of the samples were advanced (stage IIIb and IV) lung adenocarcinomas (80.77%). KIF5B-RET fusions were identified in 52% of the samples and K15-E12 was the most common variant. 6 (15%) samples harbored concurrent TP53 mutation and 3 samples were positive with EGFR mutation including a mutation in exon 19. Of these patients included, ten received cabozantinib, two received anlotinib, and one received crizotinib. Two (20%; 0–45) samples achieved stable disease and two were progressed in the cabozantinib treated group. Median progression-free survival (PFS) was 4 months (95% CI: 3.2–4.8) and median overall survival (OS) was 25 months (95% CI: 1.5–48.5). Three (11.54%; 0–24) samples achieved partial response in patients without RET inhibitor treatment and 4 (15.38%; 2–29) were stable disease. The median PFS was 11 months (95% CI: 1.2–20.8). There was no significant difference in PFS and OS between groups with or without RET inhibitors treatment.

Conclusion

This study provided insight into the RET fusions patients treatment. The survival benefit of current RET inhibitors was limited. More precise and potent RET inhibitors should be developed in the near future.

Status of 10 targeted genes of non-small cell lung cancer in eastern China: A study of 884 patients based on NGS in a single institution

BACKGROUND

The status of targeted genes and the association between targeted genes and clinicopathological features in Chinese lung cancer patients remains to be elucidated.

METHODS

The status of 10 targeted genes was evaluated by next-generation sequencing (NGS) in 884 non-small cell lung cancer (NSCLC) patients. The relationship between gene alterations and clinicopathological characters was analyzed.

RESULTS

Overall, 684 (77.4%) patients harbored gene alterations, and EGFR (510, 57.7%) was found to be the most common type of mutation followed by KRAS (91, 10.3%), HER2 (38, 4.3%), PIK3CA (32, 3.6%), ALK (21, 2.4%), BRAF (10, 1.1%), ROS1 (5, 0.6%), RET (5, 0.6%), MET (4, 0.5%) and NRAS (1, 0.1%). Gene alterations were more frequent in females, non-smokers and adenocarcinoma (P < 0.001). EGFR mutations were associated with women, non-smokers, normal level of serum tumor markers, and adenocarcinoma (P < 0.001). Patients without lymph node metastasis (P = 0.012), or early stage disease (P < 0.001) exhibited a higher EGFR mutation rate. KRAS mutations tended to arise in men (P < 0.001), smokers (P < 0.001) and patients with higher levels of serum tumor markers (P = 0.048). A mucus-producing component was associated with KRAS (P < 0.001), ROS1 (P = 0.033) and ALK (P < 0.001) alterations. ALK and ROS1 rearrangements were more frequent in micropapillary structures (P = 0.004, P = 0.012). BRAF mutation was associated with advanced disease patients and micropapillary structure (P < 0.001). PIK3CA mutation was more likely to be found in elderly patients (P = 0.014). Some patients had synchronous gene alterations, including EGFR/PIK3CA, EGFR/HER2, HER2/KRAS, EGFR/KRAS, EGFR/ROS1, EGFR/NRAS, KRAS/PIK3CA, KRAS/PIK3CA/HER2.

CONCLUSIONS

Most patients had at least one genetic alteration, and individual patients harbored synchronous mutation. Each gene alteration had unique clinicopathological characteristics.

KEY POINTS

SIGNIFICANT FINDINGS OF THE STUDY: This study revealed the frequency and distribution of 10 targeted gene abnormalities and their association with clinicopathological parameters of Chinese non-small cell lung cancer (NSCLC) patients in eastern China.

WHAT THIS STUDY ADDS

Some rare synchronous mutations were detected in our study by next-generation sequencing (NGS).

The Tripartite Nexus: Autophagy, Cancer, and Tripartite Motif-Containing Protein Family Members

Autophagy is a cellular degradative process that has multiple important actions in cancer. Autophagy modulation is under consideration as a promising new approach to cancer therapy. However, complete autophagy dysregulation is likely to have substantial undesirable side effects. Thus, more targeted approaches to autophagy modulation may prove clinically beneficial. One potential avenue to achieving this goal is to focus on the actions of tripartite motif-containing protein family members (TRIMs). TRIMs have key roles in an array of cellular processes, and their dysregulation has been extensively linked to cancer risk and prognosis. As detailed here, emerging data shows that TRIMs can play important yet context-dependent roles in controlling autophagy and in the selective targeting of autophagic substrates. This review covers how the autophagy-related actions of TRIM proteins contribute to cancer and the possibility of targeting TRIM-directed autophagy in cancer therapy.

Downregulation of hsa-microRNA-204-5p and identification of its potential regulatory network in non-small cell lung cancer: RT-qPCR, bioinformatic- and meta-analyses

Background

Pulmonary malignant neoplasms have a high worldwide morbidity and mortality, so the study of these malignancies using microRNAs (miRNAs) has attracted great interest and enthusiasm. The aim of this study was to determine the clinical effect of hsa-microRNA-204-5p (miR-204-5p) and its underlying molecular mechanisms in non-small cell lung cancer (NSCLC).

Methods

Expression of miR-204-5p was investigated by real-time quantitative PCR (RT-qPCR). After data mining from public online repositories, several integrative assessment methods, including receiver operating characteristic (ROC) curves, hazard ratios (HR) with 95% confidence intervals (95% CI), and comprehensive meta-analyses, were conducted to explore the expression and clinical utility of miR-204-5p. The potential objects regulated and controlled by miR-204-5p in the course of NSCLC were identified by estimated target prediction and analysis. The regulatory network of miR-204-5p, with its target genes and transcription factors (TFs), was structured from database evidence and literature references.

Results

The expression of miR-204-5p was downregulated in NSCLC, and the downtrend was related to gender, histological type, vascular invasion, tumor size, clinicopathologic grade and lymph node metastasis (P<0.05). MiR-204-5p was useful in prognosis, but was deemed unsuitable at present as an auxiliary diagnostic or prognostic risk factor for NSCLC due to the lack of statistical significance in meta-analyses and absence of large-scale investigations. Gene enrichment and annotation analyses identified miR-204-5p candidate targets that took part in various genetic activities and biological functions. The predicted TFs, like MAX, MYC, and RUNX1, interfered in regulatory networks involving miR-204-5p and its predicted hub genes, though a modulatory loop or axis of the miRNA-TF-gene that was out of range with shortage in database prediction, experimental proof and literature confirmation.

Conclusions

The frequently observed decrease in miR-204-5p was helpful for NSCLC diagnosis. The estimated target genes and TFs contributed to the anti-oncogene effects of miR-204-5p.

RET fusions in solid tumors

The RET proto-oncogene has been well-studied. RET is involved in many different physiological and developmental functions. When altered, RET mutations influence disease in a variety of organ systems from Hirschsprung's disease and multiple endocrine neoplasia 2 (MEN2) to papillary thyroid carcinoma (PTC) and non-small cell lung cancer (NSCLC). Changes in RET expression have been discovered in 30-70% of invasive breast cancers and 50-60% of pancreatic ductal adenocarcinomas in addition to colorectal adenocarcinoma, melanoma, small cell lung cancer, neuroblastoma, and small intestine neuroendocrine tumors. RET mutations have been associated with tumor proliferation, invasion, and migration. RET fusions or rearrangements are somatic juxtapositions of 5' sequences from other genes with 3' RET sequences encoding tyrosine kinase. RET rearrangements occur in approximately 2.5-73% of sporadic PTC and 1-3% of NSCLC patients. The most common RET fusions are CDCC6-RET and NCOA4-RET in PTC and KIF5B-RET in NSCLC. Tyrosine kinase inhibitors are drugs that target kinases such as RET in RET-driven (RET-mutation or RET-fusion-positive) disease. Multikinase inhibitors (MKI) target various kinases and other receptors. Several MKIs are FDA-approved for cancer therapy (sunitinib, sorafenib, vandetanib, cabozantinib, regorafenib, ponatinib, lenvatinib, alectinib) and non-oncologic disease (nintedanib). Selective RET inhibitor drugs LOXO-292 (selpercatinib) and BLU-667 (pralsetinib) are also undergoing phase I/II and I clinical trials, respectively, with preliminary results demonstrating partial response and low incidence of serious adverse events. RET fusions provide a viable therapeutic target for oncologic treatment, and further study is warranted into the prevalence and pathogenesis of RET fusions as well as development of current and new tyrosine kinase inhibitors.

Distinctive targetable genotypes of younger patients with lung adenocarcinoma: a cBioPortal for cancer genomics data base analysis

There is still limited comprehensive genotyping data about young patients with lung adenocarcinoma. Herein, next generation sequencing (NGS) data of lung adenocarcinoma patients was retrospectively analyzed to evaluate the relationship between young age at diagnosis and the comprehensive molecular characteristics. The cBioPortal for Cancer Genomics database was queried for cancer genomic studies of lung adenocarcinoma and a cohort of 773 patients with complete cancer genomics data was selected from 2 of 11 studies. The relationship between age at diagnosis and frequency of targetable genotypes was analyzed and verified in another cohort composed of 177 Chinese lung adenocarcinoma patients undergoing NGS assay. Of the 773 eligible lung adenocarcinoma patients, younger age was associated with an increased likelihood of a targetable genotype (P < .001). Specifically, a higher prevalence of EGFR mutations (P = .005), ALK arrangements, ROS1 arrangements (P = .035) and RET arrangements (P < .001) were identified in younger patients. The frequency of KRAS mutations (P < .001) was significantly associated with older age at diagnosis and a similar trend existed for MET (P = .057) but not BRAF-V600E (P = .686) and ERBB2 (P = .083). Additionally, an age at diagnosis of 45 years was found to be a feasible cutoff point to differentiate the younger from the older patients by comprehensive molecular characteristics. These results indicated that younger patients with lung adenocarcinoma were associated with an increased likelihood of harboring a targetable genotype. Distinctive molecular characteristics were identified in patients younger than 45 years with lung adenocarcinoma, which highlights the importance of the NGS assay and personalized therapy in this subpopulation.

Targeted Therapy For RET-Rearranged Non-Small Cell Lung Cancer: Clinical Development And Future Directions

Approximately 1-2% of unselected patients with Non-small Cell Lung Cancer (NSCLC) harbor RET rearrangements resulting in enhanced cell survival and proliferation. The initial treatment strategy for RET rearranged NSCLC has been multi-target tyrosine kinase inhibition. With overall response rates (ORR) of 16-53% and a median progression-free survival (PFS) of 4.5-7.3 months these outcomes are clearly inferior to the efficacy outcomes of selective tyrosine kinase inhibitors (TKI) in other oncogene-addicted NSCLC. Additionally, multi-kinase inhibition in RET-driven NSCLC patients showed concerning rates of high-grade toxicity, mainly induced by anti-VEGFR-kinase activity. Novel selective RET inhibitors like BLU-667, LOXO-292 and RXDX-105 have been recently investigated in early phase clinical trials showing promising efficacy with a manageable toxicity profile.

Rearranged During Transfection Fusions in Non-Small Cell Lung Cancer

Identifying and targeting specific oncogenic drivers has become standard of care in the routine management of patients with lung cancer. Research is ongoing to expand the number of drug targets that can offer clinically meaningful outcomes. Rearranged during transfection (RET) fusions are the latest oncogenic driver alterations that show potential as a drug target. RET fusions occur in 1-2% of non-small cell lung cancer (NSCLC) cases. They are more commonly associated with younger age, female gender, non-smokers and Asian ethnicity. The RET kinase is abnormally activated through fusion with a partner protein such as KIF5B, CCDC6 or NCOA4. This leads to downstream intracellular signalling and enhancement of gene transcription and cell proliferation. The effectiveness of multi-kinase inhibitors in RET positive NSCLC has been explored in early phase and retrospective studies. From these studies, the most effective agents identified include cabozantanib and vandetanib. Overall response rates (ORR) vary from 18-47% across studies. In general, these agents have a manageable toxicity profile, although there are a number of off-target toxicities. Similar to the increased activity in ALK rearranged disease, pemetrexed has demonstrated superior response rates in this patient group and should be considered. Selective RET inhibitors, including LOXO-292 and BLU-667, are progressing in clinical trials. LOXO-292 has demonstrated an impressive ORR of 77% in RET positive solid tumours. It is anticipated this agent will be an effective targeted therapeutic option for patients with RET positive lung cancer.

Clinical Characteristics and Molecular Patterns of RET-Rearranged Lung Cancer in Chinese Patients

RET rearrangement has been proven as an oncogenic driver in patients with lung cancer. However, the prevalence, clinical characteristics, molecular features, and therapeutic options in RET-rearranged patients remain unclear, especially in Chinese lung cancer patients. We retrospectively collected 6,125 Chinese lung cancer patients who have been profiled using next-generation sequencing (NGS). The clinical demographics and molecular features of RET rearrangement-positive patients were analyzed. RET rearrangements were identified in 84 patients with a proportion of 1.4% in our cohort. The median age at diagnosis was 58 years, and it mainly occurred in females with adenocarcinoma histology. KIF5B-RET was the most frequent fusion type and accounted for 53.8% (57/106) of all RET fusions identified, with K15-R12 as the most frequent variant (71.9%). Among 47 RET⁺ patients profiled with larger panels, 72.3% (34/47) harbored concurrent alterations. TP53 ranked as the most common concurrent alteration, and concomitant EGFR oncogenic alterations were identified in seven patients. Moreover, an adenocarcinoma patient harboring concurrent RET fusion and EGFR L858R responded to combinatorial treatment of cabozantinib and osimertinib, with a progression-free survival of 5 months. Our study improved knowledge of clinical characteristics and molecular features of RET-rearranged lung cancers in China. It might be helpful to guide clinicians for more effective personalized diagnostic and therapeutic approaches.

Current and Future Molecular Testing in NSCLC, What Can We Expect from New Sequencing Technologies?

Recent changes in lung cancer care, including new approvals in first line and the introduction of high-throughput molecular technologies in routine testing led us to question ourselves on how deeper molecular testing may be helpful for the optimal use of targeted drugs. In this article, we review recent results in the scope of personalized medicine in lung cancer. We discuss biomarkers that have a therapeutic predictive value in lung cancer with a focus on recent changes and on the clinical value of large scale sequencing strategies. We review the use of second- and third-generation EGFR and ALK inhibitors with a focus on secondary resistance alterations. We discuss anti-BRAF and anti-MEK combo, emerging biomarkers as NRG1 and NTRKs fusions and immunotherapy. Finally, we discuss the different technical issues of comprehensive molecular profiling and show how large screenings might refine the prediction value of individual markers. Based on a review of recent publications (2012⁻2018), we address promising approaches for the treatment of patients with lung cancers and the technical challenges associated with the identification of new predictive markers.

The GDNF Family: A Role in Cancer?

The glial cell line-derived neurotrophic factor (GDNF) family of ligands (GFLs) comprising of GDNF, neurturin, artemin, and persephin plays an important role in the development and maintenance of the central and peripheral nervous system, renal morphogenesis, and spermatogenesis. Here we review our current understanding of GFL biology, and supported by recent progress in the area, we examine their emerging role in endocrine-related and other non-hormone-dependent solid neoplasms. The ability of GFLs to elicit actions that resemble those perturbed in an oncogenic phenotype, alongside mounting evidence of GFL involvement in tumor progression, presents novel opportunities for therapeutic intervention.

Clinicopathological characteristics of ROS1- and RET-rearranged NSCLC in caucasian patients: Data from a cohort of 713 non-squamous NSCLC lacking KRAS/EGFR/HER2/BRAF/PIK3CA/ALK alterations

Targeted therapies have substantially changed the management of non-small cell lung cancer (NSCLC) patients with driver oncogenes. Given the high frequency, EGFR and ALK aberrations were the first to be detected and paved the way for tyrosine kinase inhibitor (TKI) treatments. Other kinases such as ROS1 and more recently RET have emerged as promising targets, and ROS1 and RET TKIs are already available for precision medicine. We screened a large cohort of 713 Caucasian non-squamous NSCLC patients lacking EGFR/KRAS/BRAF/HER2/PI3KCA/ALK aberrations for ROS1 and RET rearrangements using fluorescence in situ hybridization to determine the frequency and clinicopathological characteristics of ROS1- and RET-positive patients. Frequencies of ROS1 and RET rearrangements were 2.1% and 2.52%, respectively. Contrary to common belief, both ROS1 and RET rearrangements were detected in patients with a history of smoking, and the RET-positive patients were not younger than the negative patients. Moreover, RET but not ROS1 rearrangement was associated with the female gender. Nearly half of the ROS1-rearranged patients were successfully treated with ROS1 TKIs. In contrast, only 5/18 RET-positive patients received off-label RET TKIs. Two patients had stable disease, and three experienced disease progression. In addition to the 18 RET-positive cases, 10 showed isolated 5' signals. The clinical relevance is unknown but if the frequency is confirmed by other groups, the question whether these patients are eligible to TKIs will arise. More potent RET TKIs are under development and may improve the response rate in RET-positive patients. Therefore, we recommend the routine implementation of RET testing in non-squamous NSCLC patients, including those with a history of smoking.

Clinicopathological characteristics and survival of ALK, ROS1 and RET rearrangements in non-adenocarcinoma non-small cell lung cancer patients

BACKGROUND

ALK, ROS1 and RET rearrangements represent 3 most frequent fusion genes in non-small cell lung cancer (NSCLC). Rearrangements of these 3 genes exist predominantly in lung adenocarcinoma while rarely in non-adenocarcinoma. Our objective was to explore the frequency, clinicopathological characteristics and survival of ALK, ROS1 and RET rearrangements in non-adenocarcinoma NSCLC patients.

METHODS

ALK, ROS1 and RET rearrangements were screened by reverse transcriptase polymerase chain reaction (RT-PCR) in patients with completely resected non-adenocarcinoma NSCLC. All positive samples were confirmed with fluorescence in situ hybridization (FISH). Survival analysis was performed with Kaplan-Meier method and log-rank for comparison.

RESULTS

A total of 385 patients underwent complete resection, including squamous cell carcinoma (n = 245), adenosquamous carcinoma (n = 85) and large cell carcinoma (n = 55). Twelve of them were identified as harboring fusion genes, including ALK (n = 7), ROS1 (n = 3) and RET (n = 2) rearrangements. The fusion frequencies of adenosquamous, squamous cell and large cell carcinomas were 8.2%, 1.6% and 1.8% respectively. Their median age was 49.5 y and 3 of them had a smoking history. No survival difference existed between fusion gene positive and negative patients (36.7 vs.50.2 months, P = 0.21).

CONCLUSION

The frequencies of ALK, ROS1 and RET rearrangements are low in non-adenocarcinoma NSCLC patients. And their clinical characteristics are similar to those in lung adenocarcinoma. Fusions of the above 3 genes are not prognostic factor for non-adnocarcinoma NSCLC patients.