Phase III study of gemcitabine and cisplatin with or without aprinocarsen, a protein kinase C-alpha antisense oligonucleotide, in patients with advanced-stage non-small-cell lung cancer

Advancements in Gene Therapy for Non-Small Cell Lung Cancer: Current Approaches and Future Prospects

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide, characterized by late diagnosis and resistance to conventional therapies. Gene therapy has emerged as a promising alternative for NSCLC therapy, especially for patients with advanced disease who have exhausted conventional treatments. This article delved into the current developments in gene therapy for NSCLC, including gene replacement and tumor suppressor gene therapy, gene silencing, CRISPR/Cas9 gene editing, and immune modulation with CAR-T cell therapy. In addition, the challenges and future prospects of gene-based therapies for NSCLC were discussed.

Clinical Applications of Antisense Oligonucleotides in Cancer: A Focus on Glioblastoma

Antisense oligonucleotides (ASOs) are promising drugs capable of modulating the protein expression of virtually any target with high specificity and high affinity through complementary base pairing. However, this requires a deep understanding of the target sequence and significant effort in designing the correct complementary drug. In addition, ASOs have been demonstrated to be well tolerated during their clinical use. Indeed, they are already used in many diseases due to pathogenic RNAs of known sequences and in several neurodegenerative diseases and metabolic diseases, for which they were given marketing authorizations (MAs) in Europe and the United States. Their use in oncology is gaining momentum with several identified targets, promising preclinical and clinical results, and recent market authorizations in the US. However, many challenges remain for their clinical use in cancer. It seems necessary to take a step back and review our knowledge of ASOs and their therapeutic uses in oncology. The objectives of this review are (i) to summarize the current state of the art of ASOs; (ii) to discuss the therapeutic use of ASOs in cancer; and (iii) to focus on ASO usage in glioblastoma, the challenges, and the perspective ahead.

Transcriptome analysis reveals PRKCA as a potential therapeutic target for overcoming cisplatin resistance in lung cancer through ferroptosis

Cisplatin-based chemotherapy is the current standard care for lung cancer patients; however, drug resistance frequently develops during treatment, thereby limiting therapeutic efficacy.The molecular mechanisms underlying cisplatin resistance remain elusive. In this study, we conducted an analysis of microarray data from the Gene Expression Omnibus (GEO) database under the accession numbers GSE21656, which encompassed expression profiling of cisplatin-resistant H460 (DDP-H460)and the parental cells (H460). Subsequently, we calculated the differentially expressed genes (DEGs) between DDP-H460 and H460. Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of DEGs demonstrated significant impact on the Rap1, PI3K/AKT and MAPK signaling pathways. Moreover, protein and protein interaction (PPI) network analysis identified PRKCA, DET1, and UBE2N as hub genes that potentially contribute predominantly to cisplatin resistance. Ultimately, PRKCA was selected for validation due to its significant prognostic effect, which predicts unfavorable overall survival and disease-free survival in patients with lung cancer. Network analysis conducted on The Cancer Genome Atlas (TCGA) database revealed a strong gene-level correlation between PRKCA and TP53, CDKN2A, BYR2, TTN, KRAS, and PIK3CA; whereas at the protein level, it exhibited a high correlation with EGFR, Lck, Bcl2, and Syk. The in vitro experiments revealed that PRKCA was upregulated in the cisplatin-resistant A549 cells (DDP-A549), while knockdown of PRKCA increased DDP-A549 apoptosis upon cisplatin treatment. Moreover, we observed that PRKCA knockdown attenuated DDP-A549 proliferation, migration and invasion ability. Western blot analysis demonstrated that PRKCA knockdown downregulated phosphorylation of PI3K expression while upregulated the genes involved in ferroptosis signaling. In summary, our results elucidate the role of PRKCA in acquiring resistance to cisplatin and underscore its potential as a therapeutic target for cisplatin-resistant lung cancer.

An Update on Protein Kinases as Therapeutic Targets-Part I: Protein Kinase C Activation and Its Role in Cancer and Cardiovascular Diseases

Protein kinases are one of the most significant drug targets in the human proteome, historically harnessed for the treatment of cancer, cardiovascular disease, and a growing number of other conditions, including autoimmune and inflammatory processes. Since the approval of the first kinase inhibitors in the late 1990s and early 2000s, the field has grown exponentially, comprising 98 approved therapeutics to date, 37 of which were approved between 2016 and 2021. While many of these small-molecule protein kinase inhibitors that interact orthosterically with the protein kinase ATP binding pocket have been massively successful for oncological indications, their poor selectively for protein kinase isozymes have limited them due to toxicities in their application to other disease spaces. Thus, recent attention has turned to the use of alternative allosteric binding mechanisms and improved drug platforms such as modified peptides to design protein kinase modulators with enhanced selectivity and other pharmacological properties. Herein we review the role of different protein kinase C (PKC) isoforms in cancer and cardiovascular disease, with particular attention to PKC-family inhibitors. We discuss translational examples and carefully consider the advantages and limitations of each compound (Part I). We also discuss the recent advances in the field of protein kinase modulators, leverage molecular docking to model inhibitor-kinase interactions, and propose mechanisms of action that will aid in the design of next-generation protein kinase modulators (Part II).

Potential implications of protein kinase Cα in pathophysiological conditions and therapeutic interventions

PKCα is a molecule with many functions that play an important role in cell survival and death to maintain cellular homeostasis. Alteration in the normal functioning of PKCα is responsible for the complicated etiology of many pathologies, including cancer, cardiovascular diseases, kidney complications, neurodegenerative diseases, diabetics, and many others. Several studies have been carried out over the years on this kinase's function, and regulation in normal physiology and pathological conditions. A lot of data with antithetical results have therefore accumulated over time to create a complex framework of physiological implications connected to the PKCα function that needs comprehensive elucidation. In light of this information, we critically analyze the multiple roles played by PKCα in basic cellular processes and their molecular mechanism during various pathological conditions. This review further discusses the current approaches to manipulating PKCα signaling amplitude in the patient's favour and proposed PKCα as a therapeutic target to reverse pathological states.

Protein Kinase C at the Crossroad of Mutations, Cancer, Targeted Therapy and Immune Response

The frequent PKC dysregulations observed in many tumors have made these enzymes natural targets for anticancer applications. Nevertheless, this considerable interest in the development of PKC modulators has not led to the expected therapeutic benefits, likely due to the complex biological activities regulated by PKC isoenzymes, often playing ambiguous and protective functions, further driven by the occurrence of mutations. The structure, regulation and functions of PKCs have been extensively covered in other publications. Herein, we focused on PKC alterations mostly associated with complete functional loss. We also addressed the modest yet encouraging results obtained targeting PKC in selected malignancies and the more frequent negative clinical outcomes. The reported observations advocate the need for more selective molecules and a better understanding of the involved pathways. Furthermore, we underlined the most relevant immune mechanisms controlled by PKC isoforms potentially impacting the immune checkpoint inhibitor blockade-mediated immune recovery. We believe that a comprehensive examination of the molecular features of the tumor microenvironment might improve clinical outcomes by tailoring PKC modulation. This approach can be further supported by the identification of potential response biomarkers, which may indicate patients who may benefit from the manipulation of distinctive PKC isoforms.

HIF-1-dependent heme synthesis promotes gemcitabine resistance in human non-small cell lung cancers via enhanced ABCB6 expression

Gemcitabine is commonly used to treat various cancer types, including human non-small cell lung cancer (NSCLC). However, even cases that initially respond rapidly commonly develop acquired resistance, limiting our ability to effectively treat advanced NSCLC. To gain insight for developing a strategy to overcome gemcitabine resistance, the present study investigated the mechanism of gemcitabine resistance in NSCLC according to the involvement of ATP-binding cassette subfamily B member 6 (ABCB6) and heme biosynthesis. First, an analysis of ABCB6 expression in human NSCLCs was found to be associated with poor prognosis and gemcitabine resistance in a hypoxia-inducible factor (HIF)-1-dependent manner. Further experiments showed that activation of HIF-1α/ABCB6 signaling led to intracellular heme metabolic reprogramming and a corresponding increase in heme biosynthesis to enhance the activation and accumulation of catalase. Increased catalase levels diminished the effective levels of reactive oxygen species, thereby promoting gemcitabine-based resistance. In a mouse NSCLC model, inhibition of HIF-1α or ABCB6, in combination with gemcitabine, strongly restrained tumor proliferation, increased tumor cell apoptosis, and prolonged animal survival. These results suggest that, in combination with gemcitabine-based chemotherapy, targeting HIF-1α/ABCB6 signaling could result in enhanced tumor chemosensitivity and, thus, may improve outcomes in NSCLC patients.

Antisense Oligonucleotide-Mediated Splice Switching: Potential Therapeutic Approach for Cancer Mitigation

Splicing is an essential process wherein precursor messenger RNA (pre-mRNA) is reshaped into mature mRNA. In alternative splicing, exons of any pre-mRNA get rearranged to form mRNA variants and subsequently protein isoforms, which are distinct both by structure and function. On the other hand, aberrant splicing is the cause of many disorders, including cancer. In the past few decades, developments in the understanding of the underlying biological basis for cancer progression and therapeutic resistance have identified many oncogenes as well as carcinogenic splice variants of essential genes. These transcripts are involved in various cellular processes, such as apoptosis, cell signaling and proliferation. Strategies to inhibit these carcinogenic isoforms at the mRNA level are promising. Antisense oligonucleotides (AOs) have been developed to inhibit the production of alternatively spliced carcinogenic isoforms through splice modulation or mRNA degradation. AOs can also be used to induce splice switching, where the expression of an oncogenic protein can be inhibited by the induction of a premature stop codon. In general, AOs are modified chemically to increase their stability and binding affinity. One of the major concerns with AOs is efficient delivery. Strategies for the delivery of AOs are constantly being evolved to facilitate the entry of AOs into cells. In this review, the different chemical modifications employed and delivery strategies applied are discussed. In addition to that various AOs in clinical trials and their efficacy are discussed herein with a focus on six distinct studies that use AO-mediated exon skipping as a therapeutic strategy to combat cancer.

Activators and Inhibitors of Protein Kinase C (PKC): Their Applications in Clinical Trials

Protein kinase C (PKC), a family of phospholipid-dependent serine/threonine kinase, is classed into three subfamilies based on their structural and activation characteristics: conventional or classic PKC isozymes (cPKCs; α, βI, βII, and γ), novel or non-classic PKC isozymes (nPKCs; δ, ε, η, and θ), and atypical PKC isozymes (aPKCs; ζ, ι, and λ). PKC inhibitors and activators are used to understand PKC-mediated intracellular signaling pathways and for the diagnosis and treatment of various PKC-associated diseases, such as cancers, neurological diseases, cardiovascular diseases, and infections. Many clinical trials of PKC inhibitors in cancers showed no significant clinical benefits, meaning that there is a limitation to design a cancer therapeutic strategy targeting PKC alone. This review will focus on the activators and inhibitors of PKC and their applications in clinical trials.

Noncoding RNA therapeutics - challenges and potential solutions

Therapeutic targeting of noncoding RNAs (ncRNAs), such as microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), represents an attractive approach for the treatment of cancers, as well as many other diseases. Over the past decade, substantial effort has been made towards the clinical application of RNA-based therapeutics, employing mostly antisense oligonucleotides and small interfering RNAs, with several gaining FDA approval. However, trial results have so far been ambivalent, with some studies reporting potent effects whereas others demonstrated limited efficacy or toxicity. Alternative entities such as antimiRNAs are undergoing clinical testing, and lncRNA-based therapeutics are gaining interest. In this Perspective, we discuss key challenges facing ncRNA therapeutics - including issues associated with specificity, delivery and tolerability - and focus on promising emerging approaches that aim to boost their success.

Protein Kinase C as a Therapeutic Target in Non-Small Cell Lung Cancer

Driver-directed therapeutics have revolutionized cancer treatment, presenting similar or better efficacy compared to traditional chemotherapy and substantially improving quality of life. Despite significant advances, targeted therapy is greatly limited by resistance acquisition, which emerges in nearly all patients receiving treatment. As a result, identifying the molecular modulators of resistance is of great interest. Recent work has implicated protein kinase C (PKC) isozymes as mediators of drug resistance in non-small cell lung cancer (NSCLC). Importantly, previous findings on PKC have implicated this family of enzymes in both tumor-promotive and tumor-suppressive biology in various tissues. Here, we review the biological role of PKC isozymes in NSCLC through extensive analysis of cell-line-based studies to better understand the rationale for PKC inhibition. PKC isoforms α, ε, η, ι, ζ upregulation has been reported in lung cancer, and overexpression correlates with worse prognosis in NSCLC patients. Most importantly, PKC isozymes have been established as mediators of resistance to tyrosine kinase inhibitors in NSCLC. Unfortunately, however, PKC-directed therapeutics have yielded unsatisfactory results, likely due to a lack of specific evaluation for PKC. To achieve satisfactory results in clinical trials, predictive biomarkers of PKC activity must be established and screened for prior to patient enrollment. Furthermore, tandem inhibition of PKC and molecular drivers may be a potential therapeutic strategy to prevent the emergence of resistance in NSCLC.

The complexities of PKCα signaling in cancer

Protein kinase C α (PKCα) is a ubiquitously expressed member of the PKC family of serine/threonine kinases with diverse functions in normal and neoplastic cells. Early studies identified anti-proliferative and differentiation-inducing functions for PKCα in some normal tissues (e.g., regenerating epithelia) and pro-proliferative effects in others (e.g., cells of the hematopoietic system, smooth muscle cells). Additional well documented roles of PKCα signaling in normal cells include regulation of the cytoskeleton, cell adhesion, and cell migration, and PKCα can function as a survival factor in many contexts. While a majority of tumors lose expression of PKCα, others display aberrant overexpression of the enzyme. Cancer-related mutations in PKCα are uncommon, but rare examples of driver mutations have been detected in certain cancer types (e. g., choroid gliomas). Here we review the role of PKCα in various cancers, describe mechanisms by which PKCα affects cancer-related cell functions, and discuss how the diverse functions of PKCα contribute to tumor suppressive and tumor promoting activities of the enzyme. We end the discussion by addressing mutations and expression of PKCα in tumors and the clinical relevance of these findings.

The Challenges and Strategies of Antisense Oligonucleotide Drug Delivery

Antisense oligonucleotides (ASOs) are used to selectively inhibit the translation of disease-associated genes via Ribonuclease H (RNaseH)-mediated cleavage or steric hindrance. They are being developed as a novel and promising class of drugs targeting a wide range of diseases. Despite the great potential and numerous ASO drugs in preclinical research and clinical trials, there are many limitations to this technology. In this review we will focus on the challenges of ASO delivery and the strategies adopted to improve their stability in the bloodstream, delivery to target sites, and cellular uptake. Focusing on liposomal delivery, we will specifically describe liposome-incorporated growth factor receptor-bound protein-2 (Grb2) antisense oligodeoxynucleotide BP1001. BP1001 is unique because it is uncharged and is essentially non-toxic, as demonstrated in preclinical and clinical studies. Additionally, its enhanced biodistribution makes it an attractive therapeutic modality for hematologic malignancies as well as solid tumors. A detailed understanding of the obstacles that ASOs face prior to reaching their targets and continued advances in methods to overcome them will allow us to harness ASOs’ full potential in precision medicine.

Recent Advances in Oligonucleotide Therapeutics in Oncology

Cancer is one of the leading causes of death worldwide. Conventional therapies, including surgery, radiation, and chemotherapy have achieved increased survival rates for many types of cancer over the past decades. However, cancer recurrence and/or metastasis to distant organs remain major challenges, resulting in a large, unmet clinical need. Oligonucleotide therapeutics, which include antisense oligonucleotides, small interfering RNAs, and aptamers, show promising clinical outcomes for disease indications such as Duchenne muscular dystrophy, familial amyloid neuropathies, and macular degeneration. While no approved oligonucleotide drug currently exists for any type of cancer, results obtained in preclinical studies and clinical trials are encouraging. Here, we provide an overview of recent developments in the field of oligonucleotide therapeutics in oncology, review current clinical trials, and discuss associated challenges.

RNA-based therapies: A cog in the wheel of lung cancer defense

Lung cancer (LC) is a heterogeneous disease consisting mainly of two subtypes, non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), and remains the leading cause of death worldwide. Despite recent advances in therapies, the overall 5-year survival rate of LC remains less than 20%. The efficacy of current therapeutic approaches is compromised by inherent or acquired drug-resistance and severe off-target effects. Therefore, the identification and development of innovative and effective therapeutic approaches are critically desired for LC. The development of RNA-mediated gene inhibition technologies was a turning point in the field of RNA biology. The critical regulatory role of different RNAs in multiple cancer pathways makes them a rich source of targets and innovative tools for developing anticancer therapies. The identification of antisense sequences, short interfering RNAs (siRNAs), microRNAs (miRNAs or miRs), anti-miRs, and mRNA-based platforms holds great promise in preclinical and early clinical evaluation against LC. In the last decade, RNA-based therapies have substantially expanded and tested in clinical trials for multiple malignancies, including LC. This article describes the current understanding of various aspects of RNA-based therapeutics, including modern platforms, modifications, and combinations with chemo-/immunotherapies that have translational potential for LC therapies.

Novel Analgesics with Peripheral Targets

A limited number of peripheral targets generate pain. Inflammatory mediators can sensitize these. The review addresses targets acting exclusively or predominantly on sensory neurons, mediators involved in inflammation targeting sensory neurons, and mediators involved in a more general inflammatory process, of which an analgesic effect secondary to an anti-inflammatory effect can be expected. Different approaches to address these systems are discussed, including scavenging proinflammatory mediators, applying anti-inflammatory mediators, and inhibiting proinflammatory or facilitating anti-inflammatory receptors. New approaches are contrasted to established ones; the current stage of progress is mentioned, in particular considering whether there is data from a molecular and cellular level, from animals, or from human trials, including an early stage after a market release. An overview of publication activity is presented, considering a IuPhar/BPS-curated list of targets with restriction to pain-related publications, which was also used to identify topics.

Distinct Molecular Mechanisms Analysis of Three Lung Cancer Subtypes Based on Gene Expression Profiles

The purpose was to explore distinct molecular mechanisms of three lung cancer subtypes. GSE6044 microarray data downloaded from Gene Expression Omnibus (GEO) database were applied for identifying the differentially expressed genes (DEGs). Genetic global network was constructed to analyze the network annotation. The DEGs in the genetic global network related to small-cell lung carcinoma (SCLC), lung squamous cell carcinoma (SCC), and lung adenocarcinoma (AC) were screened. Protein-protein international networks of DEGs were constructed. Pathway enrichment analyses of DEGs in three subtypes were performed, followed by construction of interactional network among pathways. There were more DEGs screened in SCLC than in AC and SCC. The genetic global network with 341 genes and 1569 interaction edges was constructed. After annotating these DEGs into a protein interactional network, a total of 695 protein interactions related to these 36 DEGs were obtained. HSP90AA1 was the hub node with the highest degree of 81 in the annotation network. DEGs in SCLC and SCC were mainly enriched in some pathways, including cell cycle, DNA replication, and histidine metabolism; whereas DEGs in AC were enriched in complement and coagulation cascades, and extracellular matrix (ECM)-receptor interaction. Pathway interactional network was constructed with the hub node of a neuroactive ligand receptor interaction. The identified DEGs such as retinoid X receptor alpha (RXRA), cyclin-dependent kinase 2 (CDK2), histone deacetylase 2 (HDAC2), and KIT might be the target genes of lung cancer by participating in different pathways such as ECM-receptor interaction. Complement and coagulation cascades, and ECM-receptor interaction might be the specific pathways for AC; smoking might have a closer relationship with SCC.

Emerging therapies for non-small cell lung cancer

Recent advances in the field of novel anticancer agents prolong patients' survival and show a promising future. Tyrosine kinase inhibitors and immunotherapy for lung cancer are the two major areas undergoing rapid development. Although increasing novel anticancer agents were innovated, how to translate and optimize these novel agents into clinical practice remains to be explored. Besides, toxicities and availability of these drugs in specific regions should also be considered during clinical determination. Herein, we summarize emerging agents including tyrosine kinase inhibitors, checkpoint inhibitors, and other potential immunotherapy such as chimeric antigen receptor T cell for non-small cell lung cancer attempting to provide insights and perspectives of the future in anticancer treatment.

Systematic evaluation of the efficacy-effectiveness gap of systemic treatments in metastatic nonsmall cell lung cancer

The divergence between clinical trial results and real-world outcomes is largely unknown for many cancer types. The present study aims overall to assess the efficacy-effectiveness gap (difference between outcomes in clinical trials and the real world) in systemic treatment for metastatic nonsmall cell lung cancer (NSCLC).All patients diagnosed with stage IV NSCLC between 2008 and 2014 within a network of seven Dutch large teaching hospitals (Santeon) were studied. For every patient, an efficacy-effectiveness (EE) factor was calculated by dividing individual patients' overall survival (OS) by the pooled median OS assessed from clinical trials with the respective treatment.From 2989 diagnosed patients, 1214 (41%) started with first-line treatment. For all studied regimens, real-world OS was shorter than OS reported in clinical trials. Overall, the EE factor was 0.77 (95% CI 0.70-0.85; p<0.001). Real-world patients completed their treatment plan less often and proceeded less frequently to further lines of treatment. These parameters together with Eastern Cooperative Oncology Group performance status explained 35% of the variation in EE factor.Survival of patients with metastatic NSCLC treated with chemotherapy or targeted therapy in real-world practice is nearly one-quarter shorter than for patients included in trials. Patients' performance status, earlier discontinuation and fewer subsequent lines of treatment partly explained this difference.

Liposomal Grb2 antisense oligodeoxynucleotide (BP1001) in patients with refractory or relapsed haematological malignancies: a single-centre, open-label, dose-escalation, phase 1/1b trial

BACKGROUND

Activating mutations of tyrosine kinases are common in leukaemias. Oncogenic tyrosine kinases use the growth factor receptor-bound protein 2 (Grb2) for signal transduction, leading to activation of mitogen-activated protein kinase (MAPK) 1 and MAPK3 (ERK2 and ERK1). We hypothesised that inhibition of Grb2 would suppress ERK1 and ERK2 activation and inhibit leukaemia progression. To inhibit Grb2, a liposome-incorporated antisense oligodeoxynucleotide that blocks Grb2 protein expression, BP1001, was developed. We report the first phase 1 findings of BP1001.

METHODS

In this single-centre, open-label, dose-escalation phase 1/1b trial, we enrolled participants (aged ≥18 years) with refractory or relapsed acute myeloid leukaemia, Philadelphia-chromosome-positive chronic myeloid leukaemia (in chronic, accelerated, or blast phase), acute lymphoblastic leukaemia, or myelodysplastic syndrome, at MD Anderson Cancer Center (Houston, TX, USA). We used a 3 + 3 dose escalation strategy, with at least three patients enrolled at each dose level. We administered BP1001 intravenously, twice weekly, for 28 days, with a starting dose of 5 mg/m2. If two or more patients developed toxic effects of grade 3 or higher, that dose level was deemed toxic. The dose was escalated if it did not produce dose-limiting toxic effects, and patients would be sequentially enrolled into cohort 2 (10 mg/m2), cohort 3 (20 mg/m2), cohort 4 (40 mg/m2), cohort 5 (60 mg/m2), or cohort 6 (90 mg/m2). After completion of monotherapy, we assessed the safety and toxicity of BP1001 (60 or 90 mg/m2) in combination with 20 mg low-dose cytarabine (twice-daily subcutaneous injections) in a phase 1b study in patients with refractory or relapsed acute myeloid leukaemia (ie, those who were refractory to at least one previous therapy regimen and no more than one previous salvage regimen). The objectives of this study were to establish the toxicity and tolerance of escalating doses of BP1001 monotherapy in patients with refractory or relapsed leukaemia, to assess the maximum tolerated dose of BP1001, and to determine the optimal biologically active dose of BP1001, defined as a 50% reduction in Grb2 expression in circulating leukaemia cells. We also aimed to assess the in-vivo pharmacokinetics of BP1001 and tumour response. The study is completed and is registered with ClinicalTrials.gov, number NCT01159028.

FINDINGS

Between July 23, 2010, and Feb 23, 2016, we enrolled and treated 39 patients, of whom 27 were assessable for dose-limiting toxicity. The first patient treated had mucositis and hand-foot syndrome, which were assessed as possibly related to BP1001 and counted as a dose-limiting toxicity. We noted no other dose-limiting toxicities, and a maximum tolerated dose was not identified. The highest tested dose of BP1001 was 90 mg/m2. The most common grade 3-4 adverse events were cardiopulmonary disorders (25 [64%] of 39 patients), and fever (including neutropenic fever) and infections (17 [44%] patients). Grade 5 adverse events were cardiopulmonary disorders (two [5%] of 39 patients), fever (including neutropenic fever) and infections (two [5%] of 39 patients), and multi-organ failure (one [3%] of 39 patients). Nine (33%) of 27 patients who had peripheral blood blasts at the start of therapy had a reduction of 50% or more in peripheral blood blasts while receiving BP1001 montherapy. Three (10%) of 29 patients who had bone marrow blasts at the start of therapy had a reduction in bone marrow blasts of 50% or more while receiving BP1001 monotherapy. Per investigator's assessment, seven (22%) of 32 patients benefited from BP1001 monotherapy and had extended cycles of treatment. Of seven patients receiving BP1001 plus low-dose cytarabine combination therapy, two had complete remission, one had complete remission with incomplete haematological recovery, and two had stable disease with no dose-limiting toxicity; one patient died and one withdrew, both because of disease progression. There were eight deaths; none were treatment related.

INTERPRETATION

BP1001 is well tolerated, with early evidence of anti-leukaemic activity in combination with low-dose cytarabine. To further explore this anti-leukaemic activity, the efficacy of BP1001 plus low-dose cytarabine combination is being investigated in an ongoing phase 2 study in patients with previously untreated acute myeloid leukaemia who are ineligible for intensive induction therapy.

FUNDING

Bio-Path Holdings Inc.

Genetic Modification of the Lung Directed Toward Treatment of Human Disease

Genetic modification therapy is a promising therapeutic strategy for many diseases of the lung intractable to other treatments. Lung gene therapy has been the subject of numerous preclinical animal experiments and human clinical trials, for targets including genetic diseases such as cystic fibrosis and α1-antitrypsin deficiency, complex disorders such as asthma, allergy, and lung cancer, infections such as respiratory syncytial virus (RSV) and Pseudomonas, as well as pulmonary arterial hypertension, transplant rejection, and lung injury. A variety of viral and non-viral vectors have been employed to overcome the many physical barriers to gene transfer imposed by lung anatomy and natural defenses. Beyond the treatment of lung diseases, the lung has the potential to be used as a metabolic factory for generating proteins for delivery to the circulation for treatment of systemic diseases. Although much has been learned through a myriad of experiments about the development of genetic modification of the lung, more work is still needed to improve the delivery vehicles and to overcome challenges such as entry barriers, persistent expression, specific cell targeting, and circumventing host anti-vector responses.

Protein kinase C (PKC) isoforms in cancer, tumor promotion and tumor suppression

The AGC family of serine/threonine kinases (PKA, PKG, PKC) includes more than 60 members that are critical regulators of numerous cellular functions, including cell cycle and differentiation, morphogenesis, and cell survival and death. Mutation and/or dysregulation of AGC kinases can lead to malignant cell transformation and contribute to the pathogenesis of many human diseases. Members of one subgroup of AGC kinases, the protein kinase C (PKC), have been singled out as critical players in carcinogenesis, following their identification as the intracellular receptors of phorbol esters, which exhibit tumor-promoting activities. This observation attracted the attention of researchers worldwide and led to intense investigations on the role of PKC in cell transformation and the potential use of PKC as therapeutic drug targets in cancer diseases. Studies demonstrated that many cancers had altered expression and/or mutation of specific PKC genes. However, the causal relationships between the changes in PKC gene expression and/or mutation and the direct cause of cancer remain elusive. Independent studies in normal cells demonstrated that activation of PKC is essential for the induction of cell activation and proliferation, differentiation, motility, and survival. Based on these observations and the general assumption that PKC isoforms play a positive role in cell transformation and/or cancer progression, many PKC inhibitors have entered clinical trials but the numerous attempts to target PKC in cancer has so far yielded only very limited success. More recent studies demonstrated that PKC function as tumor suppressors, and suggested that future clinical efforts should focus on restoring, rather than inhibiting, PKC activity. The present manuscript provides some historical perspectives on the tumor promoting function of PKC, reviewing some of the observations linking PKC to cancer progression, and discusses the role of PKC in the pathogenesis of cancer diseases and its potential usage as a therapeutic target.

RNA-targeted therapeutics in cancer clinical trials: Current status and future directions

Recent advances in RNA delivery and target selection provide unprecedented opportunities for cancer treatment, especially for cancers that are particularly hard to treat with existing drugs. Small interfering RNAs, microRNAs, and antisense oligonucleotides are the most widely used strategies for silencing gene expression. In this review, we summarize how these approaches were used to develop drugs targeting RNA in human cells. Then, we review the current state of clinical trials of these agents for different types of cancer and outcomes from published data. Finally, we discuss lessons learned from completed studies and future directions for this class of drugs.

Cisplatin in the modern era: The backbone of first-line chemotherapy for non-small cell lung cancer

The treatment of advanced non-small cell lung cancer (NSCLC) may be changing, but the cisplatin-based doublet remains the foundation of treatment for the majority of patients with advanced NSCLC. In this respect, changes in practice to various aspects of cisplatin use, such as administration schedules and the choice of methods and frequency of monitoring for toxicities, have contributed to an incremental improvement in patient management and experience. Chemoresistance, however, limits the clinical utility of this drug in patients with advanced NSCLC. Better understanding of the molecular mechanisms of cisplatin resistance, identification of predictive markers and the development of newer, more effective and less toxic platinum agents is required. In addition to maximising potential benefits from advances in molecular biology and associated therapeutics, modification of existing cisplatin-based treatments can still lead to improvements in patient outcomes and experiences.

Antisense approach to inflammatory bowel disease: prospects and challenges

Despite the great success of anti-tumour necrosis factor-based therapies, the treatment of Crohn's disease (CD) and ulcerative colitis (UC) still remains a challenge for clinicians, as these drugs are not effective in all patients, their efficacy may wane with time, and their use can increase the risk of adverse events and be associated with the development of new immune-mediated diseases. Therefore, new therapeutic targets are currently being investigated both in pre-clinical studies and in clinical trials. Among the technologies used to build new therapeutic compounds, the antisense oligonucleotide (ASO) approach is slowly gaining space in the field of inflammatory bowel diseases (IBDs), and three ASOs have been investigated in clinical trials. Systemic administration of alicaforsen targeting intercellular adhesion molecule-1, a protein involved in the recruitment of leukocytes to inflamed intestine, was not effective in CD, even though the same compound was of benefit when given as an enema to UC patients. DIMS0150, targeting nuclear factor (NF) κB-p65, a transcription factor that promotes pro-inflammatory responses, was very promising in pre-clinical studies and is currently being tested in clinical trials. Oral mongersen, targeting Smad7, an intracellular protein that inhibits transforming growth factor (TGF)-β1 activity, was safe and well tolerated by CD patients, and the results of a phase II clinical trial showed the efficacy of the drug in inducing clinical remission in patients with active disease. In this leading article, we review the rationale and the clinical data available regarding these three agents, and we discuss the challenge of using ASOs in IBD.

Venous thromboembolism and lung cancer: a review

Venous thromboembolism (VTE) is a common complication of malignancies and epidemiological studies suggest that lung cancer belonged to the group of malignancies with the highest incidence rates of VTE. Risk factors for VTE in lung cancer patients are adenocarcinoma, NSCLC in comparison with SCLC, advanced disease, pneumonectomy, chemotherapy including antiangiogenic therapy. Other risk factors are pretreatment platelet counts and increased release of TF-positive microparticles. Elevated D-dimer levels do not necessarily indicate an increased risk of VTE but have been shown to be predictive for a worse clinical outcome in lung cancer patients. Mechanisms responsible for the increase in venous thrombosis in patients with lung cancer are not understood.

Currently no biomarker is recognized as a predictor for VTE in lung cancer patients.

Although several clinical trials have reported the efficacy of antithrombotic prophylaxis in patients with lung cancer who are receiving chemotherapy, further trials are needed to assess the clinical benefit since these patients are at an increased risk of developing a thromboembolism.

The Novel Anticancer Drug Hydroxytriolein Inhibits Lung Cancer Cell Proliferation via a Protein Kinase Cα- and Extracellular Signal-Regulated Kinase 1/2-Dependent Mechanism

Membrane lipid therapy is a novel approach to rationally design or discover therapeutic molecules that target membrane lipids. This strategy has been used to design synthetic fatty acid analogs that are currently under study in clinical trials for the treatment of cancer. In this context, and with the aim of controlling tumor cell growth, we have designed and synthesized a hydroxylated analog of triolein, hydroxytriolein (HTO). Both triolein and HTO regulate the biophysical properties of model membranes, and they inhibit the growth of non-small-cell lung cancer (NSCLC) cell lines in vitro. The molecular mechanism underlying the antiproliferative effect of HTO involves regulation of the lipid membrane structure, protein kinase C-α and extracellular signal-regulated kinase activation, the production of reactive oxygen species, and autophagy. In vivo studies on a mouse model of NSCLC showed that HTO, but not triolein, impairs tumor growth, which could be associated with the relative resistance of HTO to enzymatic degradation. The data presented explain in part why olive oil (whose main component is the triacylglycerol triolein) is preventive but not therapeutic, and they demonstrate a potent effect of HTO against cancer. HTO shows a good safety profile, it can be administered orally, and it does not induce nontumor cell (fibroblast) death in vitro or side effects in mice, reflecting its specificity for cancer cells. For these reasons, HTO is a good candidate as a drug to combat cancer that acts by regulating lipid structure and function in the cancer cell membrane.

Targeting protein kinase C subtypes in pancreatic cancer

In preclinical studies, protein kinase C (PKC) enzymes have been implicated in regulating many aspects of pancreatic cancer development and progression. However, clinical Phase I or Phase II trials with compounds targeting classical PKC isoforms were not successful. Recent studies implicate that mainly atypical and novel PKC enzymes regulate oncogenic signaling pathways in pancreatic cancer. Members of these two subgroups converge signaling induced by mutant Kras, growth factors and inflammatory cytokines. Different approaches for the development of inhibitors for atypical PKC and novel PKC have been described; and new compounds include allosteric inhibitors and inhibitors that block ATP binding.

Targeting protein kinase C in sarcoma

Protein kinase C (PKC) is a family of serine/threonine tyrosine kinases that regulate many cellular processes including division, proliferation, survival, anoikis and polarity. PKC is abundant in many human cancers and aberrant PKC signalling has been demonstrated in cancer models. On this basis, PKC has become an attractive target for small molecule inhibition within oncology drug development programmes. Sarcoma is a heterogeneous group of mesenchymal malignancies. Due to their relative insensitivity to conventional chemotherapies and the increasing recognition of the driving molecular events of sarcomagenesis, sarcoma provides an excellent platform to test novel therapeutics. In this review we provide a structure-function overview of the PKC family, the rationale for targeting these kinases in sarcoma and the state of play with regard to PKC inhibition in the clinic.

Protein kinase C and cancer: what we know and what we do not

Since their discovery in the late 1970s, protein kinase C (PKC) isozymes represent one of the most extensively studied signaling kinases. PKCs signal through multiple pathways and control the expression of genes relevant for cell cycle progression, tumorigenesis and metastatic dissemination. Despite the vast amount of information concerning the mechanisms that control PKC activation and function in cellular models, the relevance of individual PKC isozymes in the progression of human cancer is still a matter of controversy. Although the expression of PKC isozymes is altered in multiple cancer types, the causal relationship between such changes and the initiation and progression of the disease remains poorly defined. Animal models developed in the last years helped to better understand the involvement of individual PKCs in various cancer types and in the context of specific oncogenic alterations. Unraveling the enormous complexity in the mechanisms by which PKC isozymes have an impact on tumorigenesis and metastasis is key for reassessing their potential as pharmacological targets for cancer treatment.

The protein kinase C (PKC) inhibitors combined with chemotherapy in the treatment of advanced non-small cell lung cancer: meta-analysis of randomized controlled trials

BACKGROUND

The application of newer signaling pathway-targeted agents has become an important addition to chemotherapy in the treatment of advanced non-small cell lung cancer (NSCLC). In this study, we evaluated the efficacy and toxicities of PKC inhibitors combined with chemotherapy versus chemotherapy alone for patients with advanced NSCLC systematically.

PATIENTS AND MATERIALS

Literature retrieval, trials selection and assessment, data collection, and statistic analysis were performed according to the Cochrane Handbook 5.1.0. The outcome measures were tumor response rate, disease control rate, progression-free survival (PFS), overall survival (OS), and adverse effects.

RESULTS

Five randomized controlled trials, comprising totally 1,005 patients, were included in this study. Meta-analysis showed significantly decreased response rate (RR 0.79; 95 % CI 0.64-0.99) and disease control rate (RR 0.90; 95 % CI 0.82-0.99) in PKC inhibitors-chemotherapy groups versus chemotherapy groups. There was no significant difference between the two treatment groups regarding progression-free survival (PFS, HR 1.05; 95 % CI 0.91-1.22) and overall survival (OS, HR 1.00; 95 % CI 0.86-1.16). The risk of grade 3/4 neutropenia, leucopenia, and thrombosis/embolism increased significantly in PKC inhibitors combination groups as compared with chemotherapy alone groups.

CONCLUSION

The use of PKC inhibitors in addition to chemotherapy was not a valid alternative for patients with advanced NSCLC.

Intracellular TCR-signaling pathway: novel markers for lymphoma diagnosis and potential therapeutic targets

Despite the immunologic functions of T-cell receptor signaling molecules being extensively investigated, their potential as immunohistochemical markers has been poorly explored. With this background, we evaluated the expression of 5 intracellular proteins-GADS, DOK2, SKAP55, ITK, and PKCα-involved in T-cell receptor signaling in normal and neoplastic hematologic tissue samples, using antibodies raised against fixation-resistant epitopes of the 5 molecules. All 5 antibodies were associated with normal T-cell differentiation. GADS, DOK2, SKAP55, and ITK turned out to be T-cell lineage-specific markers in the setting of lymphoid and myeloid precursor neoplasms but showed differential expression in peripheral T-cell lymphoma (PTCL) subtypes, being detected in PTCL/not otherwise specified (NOS) and angioimmunoblastic T-cell lymphoma but negative in anaplastic large cell lymphoma (ALCL). Peripheral B-cell lymphomas were consistently negative for ITK, with occasional cases showing expression of DOK2 and SKAP55, and a proportion (47%) of hairy cell leukemias were GADS. Notably, PKCα highlighted a defective antigen in both PTCL/NOS (6%) and angioimmunoblastic T-cell lymphoma (10%), mostly negative in ALCL, and was aberrantly expressed in classical Hodgkin lymphoma (65%), Burkitt lymphoma (48%), and plasma cell myeloma (48%). In conclusion, all five molecules evaluated play a role in T-cell differentiation in normal and neoplastic tissues. They can be applied confidently to routine sections contributing primarily to assignment of T-lineage differentiation in the setting of hematopoietic precursor neoplasms (GADS/DOK2/SKAP55/ITK) and for the differential diagnosis between ALCL and PTCL/NOS (GADS/DOK2/SKAP55/ITK) or classical Hodgkin lymphoma (PKCα). Finally, association with specific tumor subtypes may have therapeutic potential.

A phase II randomized study evaluating the addition of iniparib to gemcitabine plus cisplatin as first-line therapy for metastatic non-small-cell lung cancer

BACKGROUND

Iniparib is a novel anticancer agent initially considered a poly (ADP-ribose) polymerase (PARP) inhibitor, but subsequently shown to act via non-selective protein modification through cysteine adducts. This randomized phase II study investigated the addition of iniparib to gemcitabine-cisplatin in metastatic non-small-cell lung cancer (NSCLC) patients.

PATIENTS AND METHODS

Patients with histologically confirmed stage IV NSCLC were randomized 2 : 1 to receive gemcitabine (1250 mg/m(2), days 1/8) and cisplatin (75 mg/m(2), day 1) with [gemcitabine/cisplatin/iniparib (GCI)] or without [gemcitabine/cisplatin (GC)] iniparib (5.6 mg/kg, days 1/4/8/11) every 3 weeks for six cycles. The primary end point was the overall response rate (ORR). Secondary objectives included progression-free survival (PFS), overall survival (OS), and safety. The study was not designed for formal efficacy comparison, the control arm being to benchmark results against the literature.

RESULTS

One hundred and nineteen patients were randomized (39 GC and 80 GCI). More GCI patients were male (80% GCI and 67% GC) and had PS 0 (61% GCI and 49% GC). The ORR was 25.6% [95% confidence interval (CI) 13.0%-42.1%] with GC versus 20.0% (95% CI 11.9%-30.4%) with GCI, which did not allow rejection of the null hypothesis (ORR with GCI ≤20%; P = 0.545). Median PFS was 4.3 (95% CI 2.8-5.6) months with GC and 5.7 (95% CI 4.6-6.6) months with GCI (hazard ratio 0.89, 95% CI 0.56-1.40). Median OS was 8.5 (95% CI 5.5 to not reached) months with GC, and 12.0 (95% CI 8.9-17.1) months with GCI (hazard ratio 0.78, 95% CI 0.48-1.27). More GCI patients received second-line treatment (51% GC and 68% GCI). Toxicity was similar in the two arms. Grade 3-4 toxicities included asthenia (28% GC and 8% GCI), nausea (3% GC and 14% GCI), and decreased appetite (10% in each).

CONCLUSIONS

Addition of iniparib to GC did not improve ORR over GC alone. The GCI safety profile was comparable to GC alone. Imbalances in PS and gender distribution may have impacted study results regarding PFS and OS.

TRIAL REGISTRATION

ClinicalTrial.gov Identifier NCT01086254.

Protein Kinase C (PKC) Isozymes and Cancer

Protein kinase C (PKC) is a family of phospholipid-dependent serine/threonine kinases, which can be further classified into three PKC isozymes subfamilies: conventional or classic, novel or nonclassic, and atypical. PKC isozymes are known to be involved in cell proliferation, survival, invasion, migration, apoptosis, angiogenesis, and drug resistance. Because of their key roles in cell signaling, PKC isozymes also have the potential to be promising therapeutic targets for several diseases, such as cardiovascular diseases, immune and inflammatory diseases, neurological diseases, metabolic disorders, and multiple types of cancer. This review primarily focuses on the activation, mechanism, and function of PKC isozymes during cancer development and progression.

Combination therapy of VEGF-trap and gemcitabine results in improved anti-tumor efficacy in a mouse lung cancer model

Background

Angiogenesis is essential for the growth and metastasis of cancer. Although anti-angiogenic agents, particularly vascular endothelial growth factor (VEGF) inhibitors, have exhibited single-agent activity, there is considerable interest in combining these novel drugs with conventional chemotherapy reagents to achieve an optimal clinical efficacy. The objective of this study was to evaluate the benefits of the combination therapy of vascular endothelial growth factor trap (VEGF-Trap) with gemcitabine in a lung tumor model.

Methods

A luciferase-expressing Lewis lung carcinoma (LLC) model was established in C57BL/6J mice and tumor-bearing mice were randomized into control, VEGF-Trap, gemcitabine and VEGF-Trap/gemcitabine combination groups. Tumor growth and animal survival were monitored. Tumor microvessel density and cell proliferation were evaluated by CD31 and Ki-67 immunohistochemical analysis. TUNEL assay was performed to detect apoptotic cells. The protein levels of Cyclin D1, Pro-Caspase-3, Bcl-2, MMP2 and MMP9 in tumor extracts were examined by western blot.

Results

VEGF-Trap in combination with gemcitabine showed significantly enhanced inhibition of tumor growth and prolonged mouse survival compared to the VEGF-Trap or gemcitabine monotherapy. The VEGF-Trap/gemcitabine combination therapy not only potently inhibited tumor angiogenesis and cell proliferation, but also increased cellular apoptosis within tumor tissues. In addition, the combination treatment markedly down-regulated the expression of proliferation, anti-apoptosis and invasion related proteins.

Conclusion

Combination therapy using VEGF-Trap and gemcitabine resulted in improved anti-tumor efficacy in a lung cancer model and VEGF-Trap/gemcitabine combination might represent a promising strategy in the treatment of human lung cancer.

Protein kinase C inhibitors: a patent review (2008 - 2009)

INTRODUCTION

The protein kinase C (PKC) is a family of multifunctional isoenzymes involved in apoptosis, migration, adhesion, tumorgenesis, cardiac hypertrophy, angiogenesis, platelet function and inflammation. It also plays a vital role in the regulation of signal transduction, cell proliferation and differentiation through positive and negative regulation of the cell cycle. In this work, we reviewed the existing PKC inhibitors and several patents linked to PKC inhibitors.

AREAS COVERED

Thorough survey on the PKC inhibitors having clinical importance and patents filed for these inhibitors from 2008 - 2009 is reported.

EXPERT OPINION

PKCs are highly potential therapeutic targets for treating diabetic complications, oncological, inflammatory, immunological and dermatological disorders. The clinical trial candidates of PKCs mainly target the catalytic domain, which is highly conserved throughout the PKC family making it difficult to target a particular isoform selectively. Relatively less chemical space and fewer bisubstrate inhibitors targeting both ATP and regulatory domain are explored for PKCs, more research in these areas will be helpful in overcoming existing problems.

Protein kinase Cα suppresses Kras-mediated lung tumor formation through activation of a p38 MAPK-TGFβ signaling axis

Protein kinase C alpha (PKCα) can activate both pro- and anti-tumorigenic signaling depending upon cellular context. Here, we investigated the role of PKCα in lung tumorigenesis in vivo. Gene expression data sets revealed that primary human non-small lung cancers (NSCLC) express significantly decreased PKCα levels, indicating that loss of PKCα expression is a recurrent event in NSCLC. We evaluated the functional relevance of PKCα loss during lung tumorigenesis in three murine lung adenocarcinoma models (LSL-Kras, LA2-Kras and urethane exposure). Genetic deletion of PKCα resulted in a significant increase in lung tumor number, size, burden and grade, bypass of oncogene-induced senescence, progression from adenoma to carcinoma and a significant decrease in survival in vivo. The tumor promoting effect of PKCα loss was reflected in enhanced Kras-mediated expansion of bronchio-alveolar stem cells (BASCs), putative tumor-initiating cells, both in vitro and in vivo. LSL-Kras/Prkca(-/-) mice exhibited a decrease in phospho-p38 MAPK in BASCs in vitro and in tumors in vivo, and treatment of LSL-Kras BASCs with a p38 inhibitor resulted in increased colony size indistinguishable from that observed in LSL-Kras/Prkca(-/-) BASCs. In addition, LSL-Kras/Prkca(-/-) BASCs exhibited a modest but reproducible increase in TGFβ1 mRNA, and addition of exogenous TGFβ1 to LSL-Kras BASCs results in enhanced growth similar to untreated BASCs from LSL-Kras/Prkca(-/-) mice. Conversely, a TGFβR1 inhibitor reversed the effects of PKCα loss in LSL-Kras/Prkca(-/-) BASCs. Finally, we identified the inhibitors of DNA binding (Id) Id1-3 and the Wilm's Tumor 1 as potential downstream targets of PKCα-dependent tumor suppressor activity in vitro and in vivo. We conclude that PKCα suppresses tumor initiation and progression, at least in part, through a PKCα-p38MAPK-TGFβ signaling axis that regulates tumor cell proliferation and Kras-induced senescence. Our results provide the first direct evidence that PKCα exhibits tumor suppressor activity in the lung in vivo.

Protein kinase C, an elusive therapeutic target?

Protein kinase C (PKC) has been a tantalizing target for drug discovery ever since it was first identified as the receptor for the tumour promoter phorbol ester in 1982. Although initial therapeutic efforts focused on cancer, additional indications--including diabetic complications, heart failure, myocardial infarction, pain and bipolar disorder--were targeted as researchers developed a better understanding of the roles of eight conventional and novel PKC isozymes in health and disease. Unfortunately, both academic and pharmaceutical efforts have yet to result in the approval of a single new drug that specifically targets PKC. Why does PKC remain an elusive drug target? This Review provides a short account of some of the efforts, challenges and opportunities in developing PKC modulators to address unmet clinical needs.

Profiling of ileal carcinoids

Identification of common molecular mechanisms is needed to facilitate the development of new treatment options for patients with ileal carcinoids.

PURPOSE OF REVIEW

Recent profiling studies on ileal carcinoids were examined to obtain a comprehensive view of risk factors, genetic aberrations, and transcriptional alterations. Special attention was paid to mechanisms that could provide novel targets for therapy.

RESULTS

Genome-wide association studies have shown that single nucleotide polymorphisms (SNPs) at IL12A and DAD1 are associated with an increased risk of ileal carcinoids. Genomic profiling revealed distinct patterns of copy-number alterations in ileal carcinoids. Two groups of carcinoids could be identified by hierarchical clustering. A major group of tumors was characterized by loss on chromosome 18 followed by additional losses on chromosomes 3p, 11q, and 13. Three minimal common regions of deletions were identified at 18q21.1-q21.31, 18q22.1-q22.2, and 18q22.3-q23. A minor group of tumors was characterized by clustered gains on chromosomes 4, 5, 7, 14, and 20. Expression profiling identified three groups of ileal carcinoids by principal component analysis. Tumor progression was associated with changes in gene expression including downregulation of MIR133A. Candidate genes for targeted therapy included ERBB2/HER2, DAD1, PRKCA, RYBP, CASP1, CASP4, CASP5, VMAT1, RET, APLP1, OR51E1, GPR112, SPOCK1, RUNX1, and MIR133A.

CONCLUSION

Profiling of ileal carcinoids has revealed recurrent genetic alterations and distinct patterns of gene expression. Frequent alterations in cellular pathways and genes were identified, suggesting novel targets for therapy. Translational studies are needed to validate suggested molecular targets.

Gene therapy for lung neoplasms

Both advanced-stage lung cancer and malignant pleural mesothelioma are associated with a poor prognosis. Advances in treatment regimens for both diseases have had only a modest effect on their progressive course. Gene therapy for thoracic malignancies represents a novel therapeutic approach and has been evaluated in several clinical trials. Strategies have included induction of apoptosis, tumor suppressor gene replacement, suicide gene expression, cytokine-based therapy, various vaccination approaches, and adoptive transfer of modified immune cells. This review considers the clinical results, limitations, and future directions of gene therapy trials for thoracic malignancies.

Current and emerging medical treatments for non-small cell lung cancer: a primer for pulmonologists

Pulmonary physicians commonly develop relationships with lung cancer patients through the evaluation and staging of the disease prior to the discussion of treatment options with oncologists. Given the relationship that develops, a pulmonologist is often asked about aspects of the treatment plan that may be slightly outside of their comfort zone. The aim of this overview of medical treatment of non-small cell lung cancer is to provide the pulmonologist with an overview of the evidence guiding current practice so that they can be more comfortable answering their patients' questions while awaiting the expert opinion of the oncologist. We discuss standard chemotherapeutic agents, their common side effects, and their use in the adjuvant and neoadjuvant setting, as definitive therapy for locally advanced disease, as palliative therapy for advanced disease, and as maintenance therapy. We also discuss the mechanisms of action and side effects of targeted therapies (including inhibitors of vascular endothelial growth factor [VEGF], epidermal growth factor receptor [EGFR] signaling and the anaplastic lymphoma kinase [ALK] protein), their currently accepted uses, and upcoming phase III trials, the results of which may influence standard practice.

Protein kinase Cα promotes cell migration through a PDZ-dependent interaction with its novel substrate discs large homolog 1 (DLG1)

Protein scaffolds maintain precision in kinase signaling by coordinating kinases with components of specific signaling pathways. Such spatial segregation is particularly important in allowing specificity of signaling mediated by the 10-member family of protein kinase C (PKC) isozymes. Here we identified a novel interaction between PKCα and the Discs large homolog (DLG) family of scaffolds that is mediated by a class I C-terminal PDZ (PSD-95, disheveled, and ZO1) ligand unique to this PKC isozyme. Specifically, use of a proteomic array containing 96 purified PDZ domains identified the third PDZ domains of DLG1/SAP97 and DLG4/PSD95 as interaction partners for the PDZ binding motif of PKCα. Co-immunoprecipitation experiments verified that PKCα and DLG1 interact in cells by a mechanism dependent on an intact PDZ ligand. Functional assays revealed that the interaction of PKCα with DLG1 promotes wound healing; scratch assays using cells depleted of PKCα and/or DLG1 have impaired cellular migration that is no longer sensitive to PKC inhibition, and the ability of exogenous PKCα to rescue cellular migration is dependent on the presence of its PDZ ligand. Furthermore, we identified Thr-656 as a novel phosphorylation site in the SH3-Hook region of DLG1 that acts as a marker for PKCα activity at this scaffold. Increased phosphorylation of Thr-656 is correlated with increased invasiveness in non-small cell lung cancer lines from the NCI-60, consistent with this phosphorylation site serving as a marker of PKCα-mediated invasion. Taken together, these data establish the requirement of scaffolding to DLG1 for PKCα to promote cellular migration.

Antisense drug discovery and development

Numerous chemically modified oligonucleotides have been developed so far and show their own unique chemical properties and pharmacodynamic/pharmacokinetic characteristics. Among all non-natural nucleotides, to the best of our knowledge, only five chemistries are currently being tested in clinical trials: phosphorothioate, 2´-O-methyl RNA, 2´-O-methoxyethyl RNA, 2´,4´-bridged nucleic acid/locked nucleic acid and the phosphorodiamidate morpholino oligomer. Since phosphorothioate modification can improve the pharmacokinetics of oligonucleotides, this modification is currently used in combination with all other modifications except phosphorodiamidate morpholino oligomer. For the treatment of metabolic, cardiovascular, cancer and other systemic diseases, the phosphorothioate class of drugs is obviously helpful, while superior efficacies can be observed in phosphorodiamidate morpholino oligomer compared to other classes of oligonucleotides for the treatment of Duchenne muscular dystrophy. Which properties of antisense molecules are actually essential for clinical applications? In this article, we provide an overview of the medicinal chemistry of existing non-natural antisense molecules, as well as their clinical applications, to discuss which properties of antisense oligonuculeotides affect therapeutic potency.