A phase II trial of imatinib (ST1571) in patients with c-kit expressing relapsed small-cell lung cancer: a CALGB and NCCTG study

Actionable Driver Events in Small Cell Lung Cancer

Small cell lung cancer (SCLC) stands out as the most aggressive form of lung cancer, characterized by an extremely high proliferation rate and a very poor prognosis, with a 5-year survival rate that falls below 7%. Approximately two-thirds of patients receive their diagnosis when the disease has already reached a metastatic or extensive stage, leaving chemotherapy as the remaining first-line treatment option. Other than the recent advances in immunotherapy, which have shown moderate results, SCLC patients cannot yet benefit from any approved targeted therapy, meaning that this cancer remains treated as a uniform entity, disregarding intra- or inter-tumoral heterogeneity. Continuous efforts and technological improvements have enabled the identification of new potential targets that could be used to implement novel therapeutic strategies. In this review, we provide an overview of the most recent approaches for SCLC treatment, providing an extensive compilation of the targeted therapies that are currently under clinical evaluation and inhibitor molecules with promising results in vitro and in vivo.

Integrative Analysis of a Large Real-World Cohort of Small Cell Lung Cancer Identifies Distinct Genetic Subtypes and Insights into Histologic Transformation

Small cell lung cancer (SCLC) is a recalcitrant neuroendocrine carcinoma with dismal survival outcomes. A major barrier in the field has been the relative paucity of human tumors studied. Here we provide an integrated analysis of 3,600 "real-world" SCLC cases. This large cohort allowed us to identify new recurrent alterations and genetic subtypes, including STK11-mutant tumors (1.7%) and TP53/RB1 wild-type tumors (5.5%), as well as rare cases that were human papillomavirus-positive. In our cohort, gene amplifications on 4q12 are associated with increased overall survival, whereas CCNE1 amplification is associated with decreased overall survival. We also identify more frequent alterations in the PTEN pathway in brain metastases. Finally, profiling cases of SCLC containing oncogenic drivers typically associated with NSCLC demonstrates that SCLC transformation may occur across multiple distinct molecular cohorts of NSCLC. These novel and unsuspected genetic features of SCLC may help personalize treatment approaches for this fatal form of cancer.

SIGNIFICANCE

Minimal changes in therapy and survival outcomes have occurred in SCLC for the past four decades. The identification of new genetic subtypes and novel recurrent mutations as well as an improved understanding of the mechanisms of transformation to SCLC from NSCLC may guide the development of personalized therapies for subsets of patients with SCLC. This article is highlighted in the In This Issue feature, p. 1501.

Pulmonary cancers across different histotypes share hybrid tuft cell/ionocyte-like molecular features and potentially druggable vulnerabilities

Tuft cells are chemosensory epithelial cells in the respiratory tract and several other organs. Recent studies revealed tuft cell-like gene expression signatures in some pulmonary adenocarcinomas, squamous cell carcinomas (SQCC), small cell carcinomas (SCLC), and large cell neuroendocrine carcinomas (LCNEC). Identification of their similarities could inform shared druggable vulnerabilities. Clinicopathological features of tuft cell-like (tcl) subsets in various lung cancer histotypes were studied in two independent tumor cohorts using immunohistochemistry (n = 674 and 70). Findings were confirmed, and additional characteristics were explored using public datasets (RNA seq and immunohistochemical data) (n = 555). Drug susceptibilities of tuft cell-like SCLC cell lines were also investigated. By immunohistochemistry, 10-20% of SCLC and LCNEC, and approximately 2% of SQCC expressed POU2F3, the master regulator of tuft cells. These tuft cell-like tumors exhibited "lineage ambiguity" as they co-expressed NCAM1, a marker for neuroendocrine differentiation, and KRT5, a marker for squamous differentiation. In addition, tuft cell-like tumors co-expressed BCL2 and KIT, and tuft cell-like SCLC and LCNEC, but not SQCC, also highly expressed MYC. Data from public datasets confirmed these features and revealed that tuft cell-like SCLC and LCNEC co-clustered on hierarchical clustering. Furthermore, only tuft cell-like subsets among pulmonary cancers significantly expressed FOXI1, the master regulator of ionocytes, suggesting their bidirectional but immature differentiation status. Clinically, tuft cell-like SCLC and LCNEC had a similar prognosis. Experimentally, tuft cell-like SCLC cell lines were susceptible to PARP and BCL2 co-inhibition, indicating synergistic effects. Taken together, pulmonary tuft cell-like cancers maintain histotype-related clinicopathologic characteristics despite overlapping unique molecular features. From a therapeutic perspective, identification of tuft cell-like LCNECs might be crucial given their close kinship with tuft cell-like SCLC.

Antibody-Drug Conjugate Targeting c-Kit for the Treatment of Small Cell Lung Cancer

Lung cancer is the leading cause of cancer-related deaths. Small cell lung cancer (SCLC) accounts for 15–25% of all lung cancers. It exhibits a rapid doubling time and a high degree of invasiveness. Additionally, overexpression of c-Kit occurs in 70% of SCLC patients. In this study, we evaluated an antibody-drug conjugate (ADC) that targets c-Kit, which is a potential therapeutic agent for SCLC. First, we generated and characterized 4C9, a fully human antibody that targets c-Kit and specifically binds to SCLC cells expressing c-Kit with a binding affinity of K_D = 5.5 × 10⁻⁹ M. Then, we developed an ADC using DM1, a microtubule inhibitor, as a payload. 4C9-DM1 efficiently induced apoptosis in SCLC with an IC₅₀ ranging from 158 pM to 4 nM. An in vivo assay using a xenograft mouse model revealed a tumor growth inhibition (TGI) rate of 45% (3 mg/kg) and 59% (5 mg/kg) for 4C9-DM1 alone. Combination treatment with 4C9-DM1 plus carboplatin/etoposide or lurbinectedin resulted in a TGI rate greater than 90% compared with the vehicle control. Taken together, these results indicate that 4C9-DM1 is a potential therapeutic agent for SCLC treatment.

ABL allosteric inhibitors synergize with statins to enhance apoptosis of metastatic lung cancer cells

Targeting mitochondrial metabolism has emerged as a treatment option for cancer patients. The ABL tyrosine kinases promote metastasis, and enhanced ABL signaling is associated with a poor prognosis in lung adenocarcinoma patients. Here we show that ABL kinase allosteric inhibitors impair mitochondrial integrity and decrease oxidative phosphorylation. To identify metabolic vulnerabilities that enhance this phenotype, we utilized a CRISPR/Cas9 loss-of-function screen and identified HMG-CoA reductase, the rate-limiting enzyme of the mevalonate pathway and target of statin therapies, as a top-scoring sensitizer to ABL inhibition. Combination treatment with ABL allosteric inhibitors and statins decreases metastatic lung cancer cell survival in vitro in a synergistic manner. Notably, combination therapy in mouse models of lung cancer brain metastasis and therapy resistance impairs metastatic colonization with a concomitant increase in animal survival. Thus, metabolic combination therapy might be effective to decrease metastatic outgrowth, leading to increased survival for lung cancer patients with advanced disease.

Metabolic reprogramming in tumors is an adaptation that generates vulnerabilities that can be exploited for developing new therapies. Here Luttman et al. identify synergism between ABL allosteric inhibitors and lipophilic statins to impair metastatic lung cancer cell outgrowth and colonization, leading to increased survival in mouse models of advanced disease.

A novel anti-c-Kit antibody-drug conjugate to treat wild-type and activating-mutant c-Kit-positive tumors

c‐Kit overexpression and activating mutations, which are reported in various cancers, including gastrointestinal stromal tumor (GIST), small‐cell lung cancer (SCLC), acute myeloid leukemia, acral melanoma, and systemic mastocytosis (SM), confer resistance to tyrosine kinase inhibitors (TKIs). To overcome TKI resistance, an anti‐c‐Kit antibody–drug conjugate was developed in this study to treat wild‐type and mutant c‐Kit‐positive cancers. NN2101, a fully human IgG1, was conjugated to DM1, a microtubule inhibitor, through N‐succinimidyl‐4‐(N‐maleimidomethyl) cyclohexane‐1‐carboxylate (SMCC) (to give NN2101‐DM1). The antitumor activity of NN2101‐DM1 was evaluated in vitro and in vivo using various cancer cell lines. NN2101‐DM1 exhibited potent growth‐inhibitory activities against c‐Kit‐positive cancer cell lines. In a mouse xenograft model, NN2101‐DM1 exhibited potent growth‐inhibitory activities against imatinib‐resistant GIST and SM cells. In addition, NN2101‐DM1 exhibited a significantly higher anti‐cancer effect than carboplatin/etoposide against SCLC cells where c‐Kit does not mediate cancer pathogenesis. Furthermore, the combination of NN2101‐DM1 with imatinib in imatinib‐sensitive GIST cells induced complete remission compared with treatment with NN2101‐DM1 or imatinib alone in mouse xenograft models. These results suggest that NN2101‐DM1 is a potential therapeutic agent for wild‐type and mutant c‐Kit‐positive cancers.

Role of the ABL tyrosine kinases in the epithelial-mesenchymal transition and the metastatic cascade

The ABL kinases, ABL1 and ABL2, promote tumor progression and metastasis in various solid tumors. Recent reports have shown that ABL kinases have increased expression and/or activity in solid tumors and that ABL inactivation impairs metastasis. The therapeutic effects of ABL inactivation are due in part to ABL-dependent regulation of diverse cellular processes related to the epithelial to mesenchymal transition and subsequent steps in the metastatic cascade. ABL kinases target multiple signaling pathways required for promoting one or more steps in the metastatic cascade. These findings highlight the potential utility of specific ABL kinase inhibitors as a novel treatment paradigm for patients with advanced metastatic disease. Video abstract.

Opportunities and obstacles of targeted therapy and immunotherapy in small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive malignant tumour which accounts for approximately 13-15% of all newly diagnosed lung cancer cases. To date, platinum-based chemotherapy are still the first-line treatments for SCLC. However, chemotherapy resistance and systemic toxicity limit the long-term clinical outcome of first-line treatment in SCLC. Recent years, targeted therapy and immunotherapy have made great breakthrough in cancer therapy, and researchers aim to exploit both as a single agent or in combination with chemotherapy to improve the survival of SCLC patients, but limited effectiveness and the adverse events remain the major obstacles in the treatment of SCLC. To overcome these challenges for SCLC therapies, prevention and early diagnosis for this refractory disease is very important. At the same time, we should reveal more information about the pathogenesis of SCLC and the mechanism of drug resistance. Finally, new treatment strategies should also be taken into considerations, such as repurposing drug, optimising of targets, combination therapy strategies or prognostic biomarkers to enhance therapeutic effects and decrease the adverse events rates in SCLC patients. This article will review the molecular biology characteristics of SCLC and discuss the opportunities and obstacles of the current therapy for SCLC patients.

KinomeRun: An interactive utility for kinome target screening and interaction fingerprint analysis towards holistic visualization on kinome tree

Kinases are key targets for many of the pathological conditions. Inverse screening of ligands serves as an essential mode to identify potential kinase targets in modern drug discovery research. Hence, we intend to develop KinomeRun, a robust pipeline for inverse screening and kinome tree visualization through the seamless integration of kinome structures, docking and kinome-drug interaction fingerprint analysis. In this pipeline, the hurdle of residue numbering in kinome is also resolved by creating a common index file with the conserved kinase pocket residues for comparative interaction analysis. KinomeRun can be used to screen the ligands of interest docked against multiple kinase structures in parallel around the kinase binding site and also to filter out the targets with unique interaction patterns. This automation is essential for prioritization of kinase targets that show specificity for a given drug and will also serve as a crucial tool kit for holistic approaches in kinase drug discovery. KinomeRun is developed using python and bash programming language and is distributed freely under the GNU GPL licence-3.0 and can be downloaded at https://github.com/inpacdb/KinomeRun. The tutorial videos for installation, target screening and customized filtration are available at https://www.youtube.com/playlist?list=PLuIaEFtMVgQ7v__WigQH9ilGVxrfI1LKs and also be downloaded for offline viewing from the github link.

Imatinib modulates pro-inflammatory microenvironment with angiostatic effects in experimental lung carcinogenesis

Lung cancer has second highest rate of incidence and mortality around the world. Smoking cigarettes is the main stream cause of lung carcinogenesis along with other factors such as spontaneous mutations, inactivation of tumor suppressor genes. The present study was aimed to identify the mechanistic role of Imatinib in the chemoprevention of experimental lung carcinogenesis in rat model. Gross morphological observations for tumor formation, histological examinations, RT-PCR, Western blotting, fluorescence spectroscopy and molecular docking studies were performed to elucidate the chemopreventive effects of Imatinib and support our hypothesis by various experiments. It is evident that immuno-compromised microenvironment inside solid tumors is responsible for tumor progression and drug resistance. Therefore, it is inevitable to modulate the pro-inflammatory signaling inside solid tumors to restrict neoangiogenesis. In the present study, we observed that Imatinib could downregulate the inflammatory signaling and also attributed angiostatic effects. Moreover, Imatinib also altered the biophysical properties of BAL cells such as plasma membrane potential, fluidity and microviscosity to restrict their infiltration and thereby accumulation to mount immuno-compromised environment inside the solid tumors during angiogenesis. Our molecular docking studies suggest that immunomodulatory and angiostatic properties of Imatinib could be either independent of each other or just a case of synergistic pleiotropy. Imatinib was observed to activate the intrinsic or mitochondrial pathway of apoptosis to achieve desired effects in cancer cell killings. Interestingly, binding of Imatinib inside the catalytic domain of PARP-1 also suggests that it has caspase-independent properties in promoting cancer cell deaths.

Molecular genetic profiling of small cell lung carcinoma in a Chinese cohort

Background

Small cell lung cancer (SCLC) has unique biology and chromosomal modifications; however, only a few studies have investigated the molecular map of SCLC. The present study aimed to evaluate the genomic aberrations in patients with SCLC in a Chinese cohort.

Methods

Tumor samples of SCLC were prospectively collected from Zhejiang Cancer Hospital. A total of 5 genes [EGFR (epidermal growth factor receptor) E18, EGFR E19, EGFR E20, EGFR E21, KRAS (Kirsten rat sarcoma viral oncogene homolog) E2, BRAF E15, PTEN (phosphatase and tensin homolog deleted on chromosome ten) E5, PTEN E6, PTEN E8, PIK3CA (phosphatidylinositol 3-kinase/protein kinase B) E9, PIK3CA E20] were evaluated using direct sequencing.

Results

Between November 2012 and November 2016, 30 SCLC patients were prospectively enrolled in the study. A total of 10 genomic aberrations were detected in 30 cases (33.3%): an EGFR mutation (n=6, E19, E21), a KRAS mutation (n=1, E2), PIK3CA mutations (n=1, E20), a PTEN mutation (n=2, E5, E8). No significant differences were detected in the characteristics of patients with and without genomic aberrations or patients with and without EGFR mutation.

Conclusions

The genomic aberrations of SCLC occur, offering mutational data to clinicians might be helpful for assigning patients to appropriate clinical studies, especially the anti-EFGR and PIK3CA treatment. Moreover, whether the molecular genetic profile of the SCLC patients is correlated with the effect of anti-tumor treatment, necessitating further investigation.

Clinicopathological Correlation of Adenoid Cystic Carcinoma: A Notorious Masquerader and Clinical Paradox

Background: Adenoid cystic carcinoma (ACC) is an uncommon tumor with nonspecific clinicoradiological features thereby masquerading other nonneoplastic and neoplastic entities. Materials and Methods: Cases of ACC were retrospectively reviewed over a period of 4 years. The clinical details of these patients including fine-needle aspiration cytology (FNAC) and imaging findings were retrieved. Diagnosis was confirmed on histomorphology and supplemented with immunohistochemistry (IHC). Results:: Thirty cases of ACC were included in the study. Mean patient age was 55.5 years with a slight female preponderance. Among the 30 ACCs, 10 (33.4%) were located in submandibular gland, 7 (23.4%) in parotid gland, 6 (20%) in sublingual gland, 2 (6.7%) in lung and one each (3.33%) in nasal cavity, breast, cervix, lip, and skin of face. Preoperative imaging was suggestive of malignancy in 29 cases while a single case of parotid gland ACC was misdiagnosed as benign salivary gland neoplasm. FNAC was performed in 29 cases with a diagnostic accuracy of 82.7%. Histopathological examination showed characteristic features of ACC in all cases with perineural invasion seen in 7 cases. On IHC, positivity for cytokeratin was seen in all cases, cluster of differentiation 117 in 24 cases, thyroid transcription factor-1 in two cases and human epidermal growth factor receptor/neu in two cases. All cases were negative for estrogen receptor and progesterone receptor IHC. Mean Ki-67 score was 47.8%. Conclusion: ACCs are notorious tumors showing slow growth kinetics with propensity for perineural invasion, late recurrences, and distant metastasis. It should be kept in mind as a differential diagnosis at unusual sites other than salivary glands.

A phase 2, open-label, multi-center study of amuvatinib in combination with platinum etoposide chemotherapy in platinum-refractory small cell lung cancer patients

Background

Amuvatinib (MP-470) is a multi-targeted kinase inhibitor with potent activity against c-Kit, synergistic with DNA-damaging agents. We evaluated amuvatinib in combination with platinum-etoposide (EP) chemotherapy by objective response rate, survival, and tolerability in platinum-refractory small cell lung cancer (SCLC) patients.

Methods

This study used a Simon 2-stage design requiring ≥3 centrally confirmed responses in the first 21 subjects. Subjects received EP with 300 mg amuvatinib orally three times daily in cycles of 21 days. A three-day amuvatinib run-in period before EP occurred in Cycle 1. Subjects received the same EP chemotherapy regimen given prior to progression/relapse.

Results

Among 23 subjects treated, we observed four PRs (17.4%) per RECIST 1.1, only two of which were centrally confirmed (8.7%, response duration 119, 151 days). Three subjects (13%) had confirmed stable disease. c-Kit H-score was ≥100 in two subjects whose respective durations of disease control were 151 and 256 days.

Conclusions

The addition of amuvatinib to EP chemotherapy in unselected, platinum-refractory SCLC did not meet the primary endpoint of ≥3 confirmed responses in stage 1. However, high c-Kit expression in two subjects with durable disease control suggests the potential for further study of amuvatinib in SCLC patients with high c-Kit expression.

[Recent Advances and Future Strategies for Small Cell Lung Cancer]

小细胞肺癌是一种致死率较高的恶性肿瘤，现阶段的治疗方式有手术，化疗和放疗，但预后极差。近些年来涌现的靶向治疗和免疫治疗也都在进行着大量的临床试验，本文将对小细胞肺癌目前的治疗策略以及未来研究的方向进行综述。

Second-line pazopanib in patients with relapsed and refractory small-cell lung cancer: a multicentre phase II study of the Hellenic Oncology Research Group

Background:

Pazopanib is a tyrosine kinase inhibitor with antiangiogenic activity. Vascular endothelial growth factor expression is increased in SCLC and is correlated with poor prognosis. The efficacy and tolerance of second-line pazopanib in SCLC was evaluated.

Patients and methods:

Patients with platinum-sensitive (cohort A; n=39) and -resistant/refractory (cohort B; n=19) SCLC were enrolled in a multicentre phase II study. The primary end point was the progression-free survival rate (PFS-R) at week 8 in each cohort. Pazopanib (800 mg per day per os) was administered until progressive disease (PD). Circulating tumour cells (CTCs) were enumerated using the Cellsearch assay.

Results:

All patients were evaluable for response and toxicity. In the intention-to-treat analysis, eight (13.8%) patients achieved partial response (PR) (95% confidence interval (CI): 5.0–22.7), 20 (34.5%) stable disease (SD) and 30 (51.7%) PD. Accrual in cohort B was halted because the hard-stop rule was met; in cohort A, the PFS-R was 59% (95% CI: 43.5–74.4; PR=7, SD=16). Nine (23.1%) patients received pazopanib for >6 months and 3 of them for >12 months. One pazopanib cycle resulted to a significant decrease to the number of patients with ⩾5 CTCs/7.5 ml of blood (20%) compared with baseline (50%). The median PFS and OS for all patients was 2.5 months (95% CI: 1.9–3.1 months) and 6.0 months (95% CI: 3.8–8.2 months), respectively (cohort A: PFS=3.7 months and OS=8.0 months). No unexpected toxicity was observed.

Conclusions:

Second-line treatment with pazopanib in platinum-sensitive SCLC is well tolerated and resulted in promising objective responses and disease control; CTC enumeration might serve as a reliable surrogate biomarker of response.

Research progress in the treatment of small cell lung cancer

Small cell lung cancer (SCLC) accounts for approximately 10-15% of all lung cancers. No significant improvement has been made for patients with SCLC in the past several decades. The main progresses were the thoracic radiation and prophylactic cranial irradiation (PCI) that improved the patient survival rate. For patients with limited disease and good performance status (PS), concurrent chemoradiotherapy (CCRT) followed by PCI should be considered. For extensive disease, the combination of etoposide and platinum-based chemotherapy remains the standard treatment and consolidative thoracic radiotherapy is beneficial for patients who have a significant respond to initial chemotherapy. However, the prognosis still remains poor. Recently, efforts have been focused on molecular targets and immunotherapy. But numerous molecular targets methods have failed to show a significant clinical benefit in patients with SCLC. It is anticipated that further development of research will depend on the on-going trials for molecular targeted therapy and immunotherapy which are promising and may improve the outcomes for SCLC in the next decade.

Neuroendocrine Carcinoma of the Endometrium: A Clinicopathologic Study of 25 Cases

Neuroendocrine carcinoma (NECa) of the endometrium is an uncommon tumor. In this study, we present the clinicopathologic features of 25 such cases. The patients ranged in age from 37 to 87 years (median, 57 y) and most commonly presented with vaginal bleeding. The tumors were either pure NECa (10) or mixed with other histotypes (15), most commonly endometrioid carcinoma. The NECas were large cell type (15), small cell type (4), or a mixture of both (6). NECa was underrecognized in 89% of referral/consultation cases. All tumors were positive for ≥1 neuroendocrine marker (chromogranin, synaptophysin, CD56). Additional immunohistochemical (IHC) studies were obtained in 18 cases, with positive results as follows: keratin cocktail (17), diffuse p16 (6), PAX-8 (6), CD117 (6), and TTF-1 (1). Mismatch-repair protein expression by IHC was abnormal in 8 of 18 cases (6 MLH1/PMS2 loss; 1 MSH2/MSH6 loss; 1 MSH6 loss). According to FIGO staging, cases were distributed as follows: I (6), II (2), III (10), and IV (7). All patients underwent surgical treatment, and 20 patients received adjuvant therapy. Twelve patients died of disease (mean survival 12.3 mo). Eleven patients were alive 5 to 134 months after diagnosis, including 7 who achieved a 5-year survival (3 stage I; 4 stage III). In summary, most of our endometrial NECas were large cell type, mixed with other histotypes, and underrecognized. These tumors tend to be PAX-8 negative and may be associated with microsatellite instability. The recognition of NECa may have an impact on the treatment of the patients affected by this disease. Although NECa usually has an aggressive behavior, 28% of our patients survived at least 5 years.

Genomic Profiling of Large-Cell Neuroendocrine Carcinoma of the Lung

PURPOSE

Although large-cell neuroendocrine carcinoma (LCNEC) of the lung shares many clinical characteristics with small-cell lung cancer (SCLC), little is known about its molecular features. We analyzed lung LCNECs to identify biologically relevant genomic alterations.

EXPERIMENTAL DESIGN

We performed targeted capture sequencing of all the coding exons of 244 cancer-related genes on 78 LCNEC samples [65 surgically resected cases, including 10 LCNECs combined with non-small cell lung cancer (NSCLC) types analyzed separately, and biopsies of 13 advanced cases]. Frequencies of genetic alterations were compared with those of 141 SCLCs (50 surgically resected cases and biopsies of 91 advanced cases).

RESULTS

We found a relatively high prevalence of inactivating mutations in TP53 (71%) and RB1 (26%), but the mutation frequency in RB1 was lower than that in SCLCs (40%, P = 0.039). In addition, genetic alterations in the PI3K/AKT/mTOR pathway were detected in 12 (15%) of the tumors: PIK3CA 3%, PTEN 4%, AKT2 4%, RICTOR 5%, and mTOR 1%. Other activating alterations were detected in KRAS (6%), FGFR1 (5%), KIT (4%), ERBB2 (4%), HRAS (1%), and EGFR (1%). Five of 10 cases of LCNECs combined with NSCLCs harbored previously reported driver gene alterations, all of which were shared between the two components. The median concordance rate of candidate somatic mutations between the two components was 71% (range, 60%-100%).

CONCLUSIONS

LCNECs have a similar genomic profile to SCLC, including promising therapeutic targets, such as the PI3K/AKT/mTOR pathway and other gene alterations. Sequencing-based molecular profiling is warranted in LCNEC for targeted therapies. Clin Cancer Res; 23(3); 757-65. ©2016 AACR.

Anti-angiogenesis in Personalized Therapy of Lung Cancer

Upregulation of angiogenesis is a frequent occurrence in lung cancer and is reported to represent a negative prognostic factor. This provides a rationale for the development and evaluation of anti-angiogenic agents. To date bevacizumab, a monoclonal antibody directed against serum VEGF, is the only anti-angiogenic agent that has demonstrated improved overall survival for patients with lung cancer. Meta-analysis of trials of bevacizumab in combination with platinum-based chemotherapy for NSCLC, show a 10% reduction in the risk of death (HR 0.90, 95% CI 0.81-0.99). However, therapy with bevacizumab is limited to NSCLC patients with non-squamous histology, good performance status, no brain metastases and the absence of bleeding or thrombotic disorders. More recently, similar survival was observed in a non bevacizumab containing regimen of carboplatin, pemetrexed and maintenance pemetrexed. Multiple oral anti-angiogenic compounds have been evaluated in NSCLC, both in first-line therapy, or upon disease progression. The majority of agents have shown some evidence of activity, but none have clearly demonstrated improvements in overall survival. Increased toxicities have been observed, including an increased risk of death for some agents, limiting their development. Promising data exist for sunitinib in patients with heavily pre-treated NSCLC, and nintedanib in combination with docetaxel, as second-line therapy for NSCLC. However, these findings require validation. Currently, there is no established role for anti-angiogenic therapy in SCLC, although there is some promise for sunitinib as maintenance therapy following platinum and etoposide chemotherapy. The challenge for anti-angiogenic therapy is to understand whether treatment effects in a subpopulation, are lost among a larger unselected population of patients. There is a need for additional translational research to identify predictive biomarkers for anti-angiogenic therapy.

Targeted drugs in small-cell lung cancer

In contrast to non-small-cell lung cancer (NSCLC), few advances have been made in systemic treatment of small-cell lung cancer (SCLC) in recent years. Most patients are diagnosed with extensive stage disease and are commonly treated with platinum-based chemotherapy which, although attaining high initial objective responses, has a limited impact on survival. Due to the dismal prognosis of SCLC, novel and more effective treatment strategies are urgently needed. A deeper characterization of the genomic landscape of SCLC has led to the development of rational and promising targeted agents. However, despite a large number of clinical trials, results have been disappointing and there are still no approved targeted drugs for SCLC. Recent comprehensive genomic studies suggest SCLC is a heterogeneous disease, characterized by genomic alterations targeting a broad variety of genes, including those involved in transcription regulation and chromatin modification which seem to be a hallmark of this specific lung cancer subtype. Current research efforts are focusing on further understanding of the cellular and molecular abnormalities underlying SCLC development, progression and resistance to chemotherapy. Unraveling the genomic complexity of SCLC could be the key to optimize existing treatments, including chemotherapy and radiotherapy, and for identifying those patients most likely to benefit from selected targeted therapeutic approaches.

Small cell lung cancer: will recent progress lead to improved outcomes?

Small cell lung cancer (SCLC) is an aggressive neuroendocrine malignancy with a unique natural history characterized by a short doubling time, high growth fraction, and early development of widespread metastases. Although a chemotherapy- and radiation-sensitive disease, SCLC typically recurs rapidly after primary treatment, with only 6% of patients surviving 5 years from diagnosis. This disease has been notable for the absence of major improvements in its treatment: Nearly four decades after the introduction of a platinum-etoposide doublet, therapeutic options have remained virtually unchanged, with correspondingly little improvement in survival rates. Here, we summarize specific barriers and challenges inherent to SCLC research and care that have limited progress in novel therapeutic development to date. We discuss recent progress in basic and translational research, especially in the development of mouse models, which will provide insights into the patterns of metastasis and resistance in SCLC. Opportunities in clinical research aimed at exploiting SCLC biology are reviewed, with an emphasis on ongoing trials. SCLC has been described as a recalcitrant cancer, for which there is an urgent need for accelerated progress. The NCI convened a panel of laboratory and clinical investigators interested in SCLC with a goal of defining consensus recommendations to accelerate progress in the treatment of SCLC, which we summarize here.

Personalized Therapy of Small Cell Lung Cancer

Small cell lung cancer (SCLC) is an aggressive, poorly differentiated neuroendocrine carcinoma with distinct clinical, pathological and molecular characteristics. Despite robust responses to initial chemotherapy and radiation, the prognosis of patients with SCLC remains poor with an overall 5-year survival rate of less than 10 %. Despite the fact that numerous molecularly targeted approaches have thus far failed to demonstrate clinical utility in SCLC, further advances will rely on better definition of the biological pathways that drive survival, proliferation and metastasis. Recent next-generation, molecular profiling studies have identified many new therapeutic targets in SCLC, as well as extreme genomic instability which explains the high degree of resistance. A wide variety of anti-angiogenic agents, growth factor inhibitors, pro-apoptotic agents, and epigenetic modulators have been evaluated in SCLC and many studies of these strategies are on-going. Perhaps the most promising approaches involve agents targeting cancer stem cell pathways and immunomodulatory drugs that interfere with the PD1 and CTLA-4 pathways. SCLC offers many barriers to the development of successful therapy, including limited tumor samples, inadequate preclinical models, high mutational burden, and aggressive tumor growth which impairs functional status and hampers enrollment on clinical trials.

Gastrointestinal Stromal Tumors (GIST): A Prospective Analysis and an Update on Biomarkers and Current Treatment Concepts

Gastrointestinal stromal tumors (GIST) are the most common sarcomas of the gastrointestinal tract, with transformation typically driven by activating mutations of cKIT and less commonly platelet-derived growth factor receptor alpha (PDGFRA). Successful targeting of tyrosine-protein kinase Kit with imatinib, a tyrosine kinase inhibitor, has had a major impact in the survival of patients with GIST in both the adjuvant and metastatic setting. A recent modification of treatment guidelines for patients with localized, high-risk GIST extended the adjuvant treatment duration from 1 year to 3 years. In this paper, we review the clinical data of patients with GIST treated in the Oncology Outpatient Unit of "Attikon" University Hospital and aim to assess which patients are eligible for prolongation of adjuvant imatinib therapy as currently suggested by treatment recommendations.

Expression profiling of receptor tyrosine kinases in high-grade neuroendocrine carcinoma of the lung: a comparative analysis with adenocarcinoma and squamous cell carcinoma

Background

As the comprehensive genomic analysis of small cell lung cancer (SCLC) progresses, novel treatments for this disease need to be explored. With attention to the direct connection between the receptor tyrosine kinases (RTKs) of tumor cells and the pharmacological effects of specific inhibitors, we systematically assessed the RTK expressions of high-grade neuroendocrine carcinomas of the lung [HGNECs, including SCLC and large cell neuroendocrine carcinoma (LCNEC)].

Patients and methods

Fifty-one LCNEC and 61 SCLC patients who underwent surgical resection were enrolled in this research. As a control group, 202 patients with adenocarcinomas (ADCs) and 122 patients with squamous cell carcinomas (SQCCs) were also analyzed. All the tumors were stained with antibodies for 10 RTKs: c-Kit, EGFR, IGF1R, KDR, ERBB2, FGFR1, c-Met, ALK, RET, and ROS1.

Results

The LCNEC and SCLC patients exhibited similar clinicopathological characteristics. The IHC scores for each RTK were almost equivalent between the LCNEC and SCLC groups, but they were significantly different from those of the ADC or SQCC groups. In particular, c-Kit was the only RTK that was remarkably expressed in both LCNECs and SCLCs. On the other hand, about 20 % of the HGNEC tumors exhibited strongly positive RTK expression, and this rate was similar to those for the ADC and SQCC tumors. Intriguingly, strongly positive RTKs were almost mutually exclusive in individual tumors.

Conclusions

Compared with ADC or SQCC, LCNEC and SCLC had similar expression profiles for the major RTKs. The exclusive c-Kit positivity observed among HGNECs suggests that c-Kit might be a distinctive RTK in HGNEC.

Electronic supplementary material

The online version of this article (doi:10.1007/s00432-015-1989-z) contains supplementary material, which is available to authorized users.

Molecular histology of lung cancer: from targets to treatments

Lung cancer is the leading cause of cancer-related death worldwide with a 5-year survival rate of less than 15%, despite significant advances in both diagnostic and therapeutic approaches. Combined genomic and transcriptomic sequencing studies have identified numerous genetic driver mutations that are responsible for the development of lung cancer. In addition, molecular profiling studies identify gene products and their mutations which predict tumour responses to targeted therapies such as protein tyrosine kinase inhibitors and also can offer explanation for drug resistance mechanisms. The profiling of circulating micro-RNAs has also provided an ability to discriminate patients in terms of prognosis/diagnosis and high-throughput DNA sequencing strategies are beginning to elucidate cell signalling pathway mutations associated with oncogenesis, including potential stem cell associated pathways, offering the promise that future therapies may target this sub-population, preventing disease relapse post treatment and improving patient survival. This review provides an assessment of molecular profiling within lung cancer concerning molecular mechanisms, treatment options and disease-progression. Current areas of development within lung cancer profiling are discussed (i.e. profiling of circulating tumour cells) and future challenges for lung cancer treatment addressed such as detection of micro-metastases and cancer stem cells.

Targeted therapies for small cell lung cancer: Where do we stand?

Small cell lung cancer (SCLC) accounts for 15% of lung cancer cases and is associated with a dismal prognosis. Standard therapeutic regimens have been improved over the past decades, but without a major impact on patient survival. The development of targeted therapies based on a better understanding of the molecular basis of the disease is urgently needed. At the genetic level, SCLC appears very heterogenous, although somatic mutations targeting classical oncogenes and tumor suppressors have been reported. SCLC also possesses somatic mutations in many other cancer genes, including transcription factors, enzymes involved in chromatin modification, receptor tyrosine kinases and their downstream signaling components. Several avenues have been explored to develop targeted therapies for SCLC. So far, however, there has been limited success with these targeted approaches in clinical trials. Further progress in the optimization of targeted therapies for SCLC will require the development of more personalized approaches for the patients.

Small cell lung cancer: where do we go from here?

Small cell lung cancer (SCLC) is an aggressive disease that accounts for approximately 14% of all lung cancers. In the United States, approximately 31,000 patients are diagnosed annually with SCLC. Despite numerous clinical trials, including at least 40 phase 3 trials since the 1970s, systemic treatment for patients with SCLC has not changed significantly in the past several decades. Consequently, the 5-year survival rate remains low at <7% overall, and most patients survive for only 1 year or less after diagnosis. Unlike nonsmall cell lung cancer (NSCLC), in which major advances have been made using targeted therapies, there are still no approved targeted drugs for SCLC. Significant barriers to progress in SCLC include 1) a lack of early detection modalities, 2) limited tumor tissue for translational research (eg, molecular profiling of DNA, RNA, and/or protein alterations) because of small diagnostic biopsies and the rare use of surgical resection in standard treatment, and 3) rapid disease progression with poor understanding of the mechanisms contributing to therapeutic resistance. In this report, the authors review the current state of SCLC treatment, recent advances in current understanding of the underlying disease biology, and opportunities to advance translational research and therapeutic approaches for patients with SCLC.

Genomic profiling of small-cell lung cancer: the era of targeted therapies

The molecular profiling of small-cell lung cancer is challenging because of the difficulty in obtaining suitable tumor samples for integrative genomic analysis. While an urgent need exists for well-defined and effective therapeutic targets in small-cell lung cancer, no significant improvement has been made in treating this disease over the past 30 years. Recently, three reports describing comprehensive genomic analyses of small-cell lung cancer have been published. These reports have provided a framework of biologically relevant genes in small-cell lung cancer and have demonstrated that the genomic landscape of small-cell lung cancer was almost equivalent between Asian and Caucasian populations. Of note, these three comprehensive genomic analyses and other molecular analyses of small-cell lung cancer have contributed to the identification of patient populations that may benefit from promising targeted agents, such as those affecting the PI3K/AKT/mTOR pathway, FGFR1, RET or AURORA kinase inhibitors. Targeting small-cell lung cancer cells with tumor suppressor gene alteration based on synthetic lethality is also promising. The present review provides an overview of the biologically relevant genetic alterations and targeted therapies of small-cell lung cancer focusing on recent discoveries that could impact the management of small-cell lung cancer.

A phase II trial of the Src-kinase inhibitor saracatinib after four cycles of chemotherapy for patients with extensive stage small cell lung cancer: NCCTG trial N-0621

INTRODUCTION

To assess the efficacy and the Src-kinase inhibitor saracatinib (AZD-0530) after four cycles of platinum-based chemotherapy for extensive stage small cell lung cancer (SCLC).

METHODS

Patients with at least stable disease received saracatinib at a dose of 175 mg/day by mouth until disease progression, unacceptable toxicity, or patient refusal. The primary endpoint was the 12-week progression-free survival (PFS) rate from initiation of saracatinib treatment. Planned interim analysis in first 20 patients, where 13 or more patients alive and progression-free at 12-weeks would allow continued enrollment to 40 total patients.

RESULTS

All 23 evaluable patients received platinum based standard chemotherapy. Median age was 58 years (range: 48-82). 96% of patients had a performance status of 0/1. Median of two cycles given (range: 1-34). All 23 (100%) patients have ended treatment, most for disease progression (19/23). The 12-week PFS rate was 26% (6/23; 95% CI: 10-48%). From start of standard chemotherapy, median PFS was 4.7 months (95% CI: 4.5-5.1) and median OS was 11.2 months (95% CI: 9.9-13.8). Eight (35%) and three (13%) patients experienced at least one grade 3/4 or grade 4 AE, respectively. Commonly occurring grade 3/4 adverse events were thrombocytopenia (13%), fatigue (9%), nausea (9%), and vomiting (9%).

CONCLUSIONS

Saracatinib at a dose of 175 mg/day by mouth is well tolerated. However, the PFS rate observed at the pre-planned interim analysis did not meet the criteria for additional enrollment.

A human monoclonal antibody targeting the stem cell factor receptor (c-Kit) blocks tumor cell signaling and inhibits tumor growth

Stem cell factor receptor (c-Kit) exerts multiple biological effects on target cells upon binding its ligand stem cell factor (SCF). Aberrant activation of c-Kit results in dysregulated signaling and is implicated in the pathogenesis of numerous cancers. The development of more specific and effective c-Kit therapies is warranted given its essential role in tumorigenesis. In this study, we describe the biological properties of CK6, a fully human IgG1 monoclonal antibody against the extracellular region of human c-Kit. CK6 specifically binds c-Kit receptor with high affinity (EC 50 = 0.06 nM) and strongly blocks its interaction with SCF (IC 50 = 0.41 nM) in solid phase assays. Flow cytometry shows CK6 binding to c-Kit on the cell surface of human small cell lung carcinoma (SCLC), melanoma, and leukemia tumor cell lines. Furthermore, exposure to CK6 inhibits SCF stimulation of c-Kit tyrosine kinase activity and downstream signaling pathways such as mitogen-activated protein kinase (MAPK) and protein kinase B (AKT), in addition to reducing tumor cell line growth in vitro. CK6 treatment significantly decreases human xenograft tumor growth in NCI-H526 SCLC (T/C% = 57) and Malme-3M melanoma (T/C% = 58) models in vivo. The combination of CK6 with standard of care chemotherapy agents, cisplatin and etoposide for SCLC or dacarbazine for melanoma, more potently reduces tumor growth (SCLC T/C% = 24, melanoma T/C% = 38) compared with CK6 or chemotherapy alone. In summary, our results demonstrate that CK6 is a c-Kit antagonist antibody with tumor growth neutralizing properties and are highly suggestive of potential therapeutic application in treating human malignancies harboring c-Kit receptor.

Relative influence of c-Kit expression and epidermal growth factor receptor gene amplification on survival in patients with non-small cell lung cancer

c-Kit and epidermal growth factor receptor (EGFR) have critical roles in cell proliferation and differentiation in patients with non-small cell lung cancer (NSCLC). The present study aimed to investigate the prognostic impact of c-Kit and/or EGFR expression in tumor tissue samples from 146 patients with NSCLC. c-Kit expression was analyzed using immunohistochemistry and the expression of EGFR was assessed using fluorescence in situ hybridization. Univariate and multivariate analyses identified that c-Kit is a significant negative prognostic factor. The expression of c-Kit was correlated with poor differentiation, pleura involvement and smoking history (P=0.043, 0.007 and 0.032, respectively). Furthermore, patients with c-Kit-positive expression were associated with a significantly lower overall survival compared with those exhibiting c-Kit-negative expression (P=0.048). The median follow-up time was 19 months post-surgery. EGFR gene amplification as a result of polysomy of chromosome 7 was found to be negatively correlated with poor differentiation and smoking history (P=0.023 and 0.044, respectively). The findings of the present study indicate that c-Kit and EGFR expression is a strong, independent, negative prognostic factor in NSCLC.

Pilot phase I/II personalized therapy trial for metastatic colorectal cancer: evaluating the feasibility of protein pathway activation mapping for stratifying patients to therapy with imatinib and panitumumab

This nonrandomized phase I/II trial assessed the efficacy/tolerability of imatinib plus panitumumab in patients affected by metastatic colorectal cancer (mCRC) after stratification to treatment by selection of activated imatinib drug targets using reverse-phase protein array (RPPA). mCRC patients presenting with a biopsiable liver metastasis were enrolled. Allocation to the experimental and control arms was established using functional pathway activation mapping of c-Kit, PDGFR, and c-Abl phosphorylation by RPPA. The experimental arm received run-in escalation therapy with imatinib followed by panitumumab. The control arm received panitumumab alone. Seven patients were enrolled in the study. For three of the seven patients, sequential pre- and post-treatment biopsies were used to evaluate the effect of the therapeutic compounds on the drug targets and substrates. A decrease in the activation level of the drug targets and downstream substrates was observed in two of three patients. Combination therapy increased the activation of the AKT-mTOR pathway and several receptor tyrosine kinases. This study proposes a novel methodology for stratifying patients to personalized treatment based on the activation level of the drug targets. This workflow provides the ability to monitor changes in the signaling pathways after the administration of targeted therapies and to identify compensatory mechanisms.

Small cell lung cancer: therapies and targets

Small cell lung cancer (SCLC) remains a fatal disease due to limited therapeutic options. Systemic chemotherapy is the bedrock of treatment for both the limited and extensive stages of the disease. However, the established management paradigm of platinum-based chemotherapy has reached an efficacy plateau. A modest survival improvement, approximately 5%, was witnessed with the addition of cranial or thoracic radiation to systemic chemotherapy. Other strategies to improve outcome of platinum-based chemotherapy in the last two decades have met with minimal success. The substitution of irinotecan for etoposide in the frontline treatment of SCLC achieved significant efficacy benefit in Japanese patients, but similar benefit could not be reproduced in other patient populations. Salvage treatment for recurrent or progressive SCLC is particularly challenging, where topotecan remains the only agent with regulatory approval to date. Ongoing evaluation of biologic agents targeting angiogenesis, sonic hedgehog pathway, DNA repair pathway, and immune checkpoint modulators hold some promise for improved outcome in SCLC. It is hoped that the coming decade will witness the application of new molecular biology and genomic research techniques to improve our understanding of SCLC biology and identification of molecular subsets that can be targeted appropriately using established and emerging biological agents similar to the accomplishments of the last decade with non-small cell lung cancer (NSCLC).

Progress in the management of limited-stage small cell lung cancer

Approximately 15% of lung cancer cases are of the small cell subtype, but this variant is highly aggressive and is often diagnosed at advanced stages. Outcomes after current treatment regimens have been poor, with 5-year survival rates as low as 25% for patients with limited-stage disease. Advances in therapy for small cell lung cancer have included the development of more effective chemotherapeutic agents and radiation techniques. For example, hyperfractionated radiotherapy given early in the course of the disease can reduce local recurrence and extend survival. Other technologic advances in radiation planning and delivery such as intensity-modulated radiotherapy, image-guided adaptive radiotherapy, and 4-dimensional computed tomography/positron emission tomography have facilitated the design of treatment volumes that closely conform to the shape of the tumor, which allows higher radiation doses to be given while minimizing radiation-induced toxicity to adjacent structures. Future improvements in outcomes will require clarifying the molecular basis for this disease.

The development of targeted therapy in small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive cancer usually with distal metastasis and very poor prognosis. Chemotherapy is the treatment of choice for SCLC in all stages and an initial good response, but there is a high chance of disease relapse with an overall poor median survival for both stages. With increasing translational research and a better understanding of the molecular basis of cancer, a number of molecular targets have been identified in various preclinical studies. Targeted drugs have less toxicity than chemotherapy drugs, but no targeted agents have been approved for use in the treatment of SCLC patients to date. This review focuses on targeted therapies in SCLC.

Targeted therapies in small cell lung cancer

Lung cancer is the leading cause of cancer-related mortality. Small cell lung cancer (SCLC) accounted for 12.95% of all lung cancer histological types in 2002. Despite trends toward modest improvement in survival, the outcome remains extremely poor. Chemotherapy is the cornerstone of treatment in SCLC. More than two-thirds of patients who succumb to lung cancer in the United States are over 65 years old. Elderly patients tolerate chemotherapy poorly and need novel therapeutic agents. Targeted drugs have less toxicity than chemotherapy drugs, but no targeted agents have been approved for use in the treatment of SCLC patients to date. Certain new targeted agents, including gefitinib, bevacizumab and Bcl-2 inhibitors, offer a promise of improved outcomes, however negative results are more commonly reported than positive. This review focuses on targeted therapies in SCLC.

KIT (CD117) expression in a subset of non-small cell lung carcinoma (NSCLC) patients

We have previously described the expression of CD44, CD90, CD117 and CD133 in NSCLC tumors, adjacent normal lung, and malignant pleural effusions (MPE). Here we describe the unique subset of tumors expressing CD117 (KIT), a potential therapeutic target. Tumor and adjacent tissue were collected from 58 patients. Six MPE were obtained before therapy. Tissue was paraffin embedded for immunofluorescent microscopy, disaggregated and stained for flow cytometry or cryopreserved for later culture. The effect of imatinib on CD117(high)/KIT+ tumors was determined on first passage cells; absolute cell counts and flow cytometry were readouts for drug sensitivity of cell subsets. Primary tumors divided into KIT(neg) and KIT+ by immunofluorescence. By more sensitive flow cytometric analysis, CD117+ cytokeratin+ cells were detected in all tissues (1.1% of cytokeratin+ cells in normal lung, 1.29% in KIT "negative" tumors, 40.7% in KIT+ tumors, and 0.4% in MPE). In KIT+/CD117(high), but not KIT+/CD117(low) tumors, CD117 was overexpressed 3.1-fold compared to normal lung. Primary cultures of CD117(high) tumors were sensitive to imatinib (5 µM) in short term culture. We conclude that NSCLC tumors divide into CD117(low) and CD117(high). Overexpression of CD117 in CD117(high) NSCLC supports exploring KIT as a therapeutic target in this subset of patients.

Chemoradiotherapy in limited-disease small-cell lung cancer

SUMMARY Systemic chemotherapy is the mainstay of treatment for small-cell lung cancer. A third of small-cell lung cancer patients present with limited disease; in this population, thoracic radiotherapy caused a 14% reduction in the mortality rate, and benefit in terms of overall survival at 3 years was 5.4% as compared with chemotherapy alone. Although the optimal schedule and volume of thoracic radiotherapy remain controversial, early twice-daily concurrent radiotherapy with etoposide plus cisplatin is recommended. Prophylactic cranial irradiation is recommended for patients with any response to first-line treatment. Maintenance and dose-intense treatment is not recommended outside of clinical trials. Large randomized trials that compare standard-dose radiation therapy of 45 Gy in twice-daily fractions for 3 weeks with once-daily schedules with a higher total dose are ongoing. The incorporation of new drugs is warranted for future combined modality treatment.

Expression and mutation of the c-kit gene and correlation with prognosis of small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive and lethal type of cancer in humans. SCLC is sensitive to chemotherapy and radiotherapy, but long-term survival is low and the majority of patients eventually develop progressive disease. With the success of imatinib mesylate in the treatment of gastrointestinal stromal tumors expressing c-kit, its use in SCLC serves as a novel molecular therapeutic approach. The activity of imatinib mesylate is correlated with the mutation of c-kit gene exons 9 and 11 in gastrointestinal stromal tumors. The incidence of epidermal growth factor receptor mutation in non-small cell lung cancer is higher in China than in the United States of America and European countries. There may be also differences in the incidence of c-kit mutation between China and European countries. At present, no study examining imatinib mesylate treatment for SCLC in China is available. To investigate the expression and mutation of c-kit and the correlation with prognosis of SCLC in China, immunohistochemistry was used to detect the expression of c-kit, and a pyrosequencing assay was used to detect mutations in c-kit exons 9 and 11 of 36 SCLC patients who received surgical treatment at the Zhejiang Cancer Hospital, Hangzhou, China, between 1998 and 2010. All 36 patients were followed up to analyze the correlation between prognosis and expression and mutation of c-kit. The incidence of c-kit-positive expression was 83.3%, including 25.0% weak staining, 22.2% moderate staining and 36.1% strong staining. The overall survival of patients with c-kit strong staining was shorter compared to patients with c-kit not strong staining. No mutation in c-kit exons 9 and 11 was detected. In conclusion, the findings showed that the expression of c-kit is high, and strong staining is a prognostic factor for worse survival.

Chemotherapy for small cell lung cancer: a comprehensive review

Combination chemotherapy is the current strategy of choice for treatment of small cell lung cancer (SCLC). Platinum containing combination regimens are superior to non-platinum regimens in limited stage-SCLC and possibly also in extensive stage-SCLC as first and second-line treatments. The addition of ifosfamide to platinum containing regimens may improve the outcome but at the price of increased toxicity. Suboptimal doses of chemotherapy result in inferior survival. Early intensified, accelerated and high-dose chemotherapy gave conflicting results and is not considered a standard option outside of clinical trials. A number of newer agents have provided promising results when used in combination regimens, for example, gemcitabine, irinotecan and topotecan. However, more studies are required to appropriately evaluate them. There is a definitive role for radiotherapy in LD-SCLC. However, timing and schedule are subject to further research. Novel approaches are currently being investigated in the hope of improving outcome.

Current and emerging pharmacotherapies for the treatment of relapsed small cell lung cancer

Small cell lung cancer (SCLC) is a very aggressive cancer with poor outcome if left untreated, but it is also one of the most chemotherapy responsive cancers. Overall it has a very poor prognosis especially if it is chemotherapy resistant to first line treatment. Second line chemotherapy has not been very beneficial in SCLC as opposed to breast cancer and lymphoma. In the last few years topotecan is the only drug that has been approved by the food and drug administration (FDA) for the second line treatment of SCLC but in Japan another drug, amrubicin is approved. There are many combinations of different chemotherapies available in moderate to high intensity, in this difficult to treat patient to overcome the chemo resistance, but many of these studies are small or phase II trials. In this article we have reviewed single agent and multidrug regimens that were studied in both chemo sensitive and refractory setting, including the most recent clinical trials.

Update on new drugs in small cell lung cancer

INTRODUCTION

Small cell lung cancer (SCLC) will account for 25,000 to 32,000 new lung cancer cases in the USA in 2010. Current treatmenta pproaches include platinum-based chemotherapy and etoposide with or without radiation therapy depending on stage and performance status. Five-year survival is approximately 25% for patients with limited stage disease and 1 -- 2% for patients with extensive stage disease and has noti mproved in almost two decades.

AREAS COVERED

This article reviews the results of recent clinical trials that have evaluated targeted agents and novel cytotoxic agents alone or in combination with standard chemotherapy in the treatment of patients with SCLC.

EXPERT OPINION

The lack of a targeted approach to the treatment of patients with SCLC has led investigators to evaluate a multitude of agents with overwhelmingly negative results. A more systematic approach to clinical trials in patients is needed to improve outcomes for patients with this disease.

Novel strategies for the treatment of small-cell lung carcinoma

Small-cell lung cancer (SCLC) is a disease with a poor prognosis and limited treatment options. Over the past 30 years, basic and clinical research have translated to little innovation in the treatment of this disease. The Study of Picoplatin Efficacy After Relapse (SPEAR) evaluated best supportive care with or without picoplatin for second-line SCLC treatment and failed to meet its primary end point of overall survival. As the largest second-line, randomized study in patients with SCLC, SPEAR provides an opportunity to critically examine the drug development model in this disease. In this Review, we discuss the current standard approach for the management of SCLC that progresses after first-line therapy, analyze the preliminary data that supported the evaluation of picoplatin in this setting, and critically evaluate the SPEAR trial design and results. Lastly, we present advances in the understanding of the molecular biology of SCLC that could potentially inform future clinical trials and hopefully lead to the successful development of molecular targeted agents for the treatment of this disease.