A phase 1/2a, dose-escalation, safety, pharmacokinetic, and preliminary efficacy study of intraperitoneal administration of BC-819 (H19-DTA) in subjects with recurrent ovarian/peritoneal cancer.

BACKGROUND: H19 is a paternally imprinted, oncofetal gene expressed in various embryonic tissues and in 85% of the ovarian tumors. H19-DTA (BC-819) is a DNA plasmid that drives the expression of the diphtheria toxin gene under the regulation of the H19 promoter sequence and therefore is a potential treatment for various tumors that overexpress the H19 gene, among them-ovarian cancer. OBJECTIVE: To assess the safety and efficacy of intra-peritoneal (IP) instillations of H19-DTA (BC-819) plasmid in treating ovarian/peritoneal cancer patients with advanced recurrent disease. METHODS: A phase 1-2A multi-centric trial included 14 eligible patients who were either platinum-refractory or platinum-resistant with positive H19 expression. Patients were treated IP with escalating weekly doses of BC-819 for a maximum of 6-9 weeks. Dose-limiting toxicities (DLT) were assessed after the first course of treatment for each patient and each subsequent cohort was enrolled once each subject had completed the first course of treatment and its 4-week follow-up period. The occurrence of adverse events (AEs) and response to treatment were assessed after the induction course and then periodically. RESULTS: During the study, no DLTs were observed. Only 5 grade 1 and 2 AEs, which occurred in 4 patients were considered as possibly related to BC-819. The best tumor response seen was stable disease. Median survivals of 3.2, 5.3 and 6.5 months were observed for the 60, 120 and 240 mg cohorts, respectively. CONCLUSIONS: BC-819 can be considered safe and well tolerated in intraperitoneal doses up to 240 mg. Hybridization of intraperitoneal chemotherapy with the biological treatment of BC-819 should be further evaluated in phase 2 and 3 studies.

H19 non-coding RNA in urine cells detects urothelial carcinoma: a pilot study.

CONTEXT: Urothelial carcinoma (UC) is common and highly recurrent. Diagnosis and follow-up involve invasive cystoscopies. OBJECTIVE: To evaluate H19 RNA in urine cells as diagnostic tool for UC. MATERIALS AND METHODS: RT-PCR analysis of urine samples from healthy volunteers and UC patients. RESULTS: H19 RNA was unequivocally detected in the urine of 90.5% of patients and 25.9% of controls. H19 copies were three orders of magnitude higher in patients. Receiver operating characteristic analysis showed an area under the curve of 0.933. CONCLUSIONS: This pilot study shows that urinary cell H19 is a highly sensitive test for UC and pending verification could transform patient management.

The role of the oncofetal H19 lncRNA in tumor metastasis: orchestrating the EMT-MET decision.

Long non-coding RNA (lncRNA) genes are emerging as key players in the metastatic cascade. Current evidence indicate that H19 lncRNA and the microRNA(miRNA) miR-675, which is processed from it, play crucial roles in metastasis, through the regulation of critical events specifically the epithelial to mesenchymal (EMT) and the mesenchymal to epithelial transitions (MET). This review summarizes recent mechanistic pathways and tries to put together seemingly conflicting data from different reports under one proposed general scheme underlying the various roles of H19/miR-675 in the metastatic cascade. We propose several approaches to harnessing this knowledge for translational medicine.

The H19 Long non-coding RNA in cancer initiation, progression and metastasis - a proposed unifying theory.

The imprinted oncofetal long non-coding RNA (lncRNA) H19 is expressed in the embryo, down-regulated at birth and then reappears in tumors. Its role in tumor initiation and progression has long been a subject of controversy, although accumulating data suggest that H19 is one of the major genes in cancer. It is actively involved in all stages of tumorigenesis and is expressed in almost every human cancer. In this review we delineate the various functions of H19 during the different stages in the complex process of tumor progression. H19 up-regulation allows cells to enter a "selfish" survival mode in response to stress conditions, such as destabilization of the genome and hypoxia, by accelerating their proliferation rate and increasing overall cellular resistance to stress. This response is tightly correlated with nullification, dysfunction or significant down-regulation of the master tumor suppressor gene P53. The growing evidence of H19's involvement in both proliferation and differentiation processes, together with its involvement in epithelial to mesenchymal transition (EMT) and also mesenchymal to epithelial transition (MET), has led us to conclude that some of the recent disputes and discrepancies arising from current research findings can be resolved from a viewpoint supporting the oncogenic properties of H19. According to a holistic approach, the versatile, seemingly contradictory functions of H19 are essential to, and differentially harnessed by, the tumor cell depending on its context within the process of tumor progression.

The non-coding RNAs of the H19-IGF2 imprinted loci: a focus on biological roles and therapeutic potential in Lung Cancer.

Since it was first described, the imprinted cluster 11p15.5 has been reported to be deregulated in a variety of pediatric and adult cancers including that of the lung. Both protein coding and non-coding genes functioning as oncogenes or as tumor suppressor genes reside within this cluster. Oncomirs that can function as oncogenes or as tumor suppressors have also been reported. While a complete account of the role played by the 11p15.5 imprinted cluster in lung cancer is beyond the scope of this review, we will focus on the role of the non-coding RNAs processed from the H19-IGF2 loci. A special emphasis will be given to the H19/miR-675 gene locus. Their potential diagnostic and therapeutic use in lung cancer will be described.

Oncofetal H19 RNA promotes tumor metastasis.

The oncofetal H19 gene transcribes a long non-coding RNA(lncRNA) that is essential for tumor growth. Here we found that numerous established inducers of epithelial to mesenchymal transition(EMT) also induced H19/miR-675 expression. Both TGF-ß and hypoxia concomitantly induced H19 and miR-675 with the induction of EMT markers. We identified the PI3K/AKT pathway mediating the inductions of Slug, H19 RNA and miR-675 in response to TGF-ß treatment, while Slug induction depended on H19 RNA. In the EMT induced multidrug resistance model, H19 level was also induced. In a mouse breast cancer model, H19 expression was tightly correlated with metastatic potential. In patients, we detected high H19 expression in all common metastatic sites tested, regardless of tumor primary origin. H19 RNA suppressed the expression of E-cadherin protein. H19 up-regulated Slug expression concomitant with the suppression of E-cadherin protein through a mechanism that involved miR-675. Slug also up-regulated H19 expression and activated its promoter. Altogether, these results may support the existence of a positive feedback loop between Slug and H19/miR-675, that regulates E-cadherin expression. H19 RNA enhanced the invasive potential of cancer cells in vitro and enhanced tumor metastasis in vivo. Additionally, H19 knockdown attenuated the scattering and tumorigenic effects of HGF/SF. Our results present novel mechanistic insights into a critical role for H19 RNA in tumor progression and indicate a previously unknown link between H19/miR-675, Slug and E-cadherin in the regulation of cancer cell EMT programs.

The increasing complexity of the oncofetal h19 gene locus: functional dissection and therapeutic intervention.

The field of the long non-coding RNA (lncRNA) is advancing rapidly. Currently, it is one of the most popular fields in the biological and medical sciences. It is becoming increasingly obvious that the majority of the human transcriptome has little or no-protein coding capacity. Historically, H19 was the first imprinted non-coding RNA (ncRNA) transcript identified, and the H19/IGF2 locus has served as a paradigm for the study of genomic imprinting since its discovery. In recent years, we have extensively investigated the expression of the H19 gene in a number of human cancers and explored the role of H19 RNA in tumor development. Here, we discuss recently published data from our group and others that provide further support for a central role of H19 RNA in the process of tumorigenesis. Furthermore, we focus on major transcriptional modulators of the H19 gene and discuss them in the context of the tumor-promoting activity of the H19 RNA. Based on the pivotal role of the H19 gene in human cancers, we have developed a DNA-based therapeutic approach for the treatment of cancers that have upregulated levels of H19 expression. This approach uses a diphtheria toxin A (DTA) protein expressed under the regulation of the H19 promoter to treat tumors with significant expression of H19 RNA. In this review, we discuss the treatment of four cancer indications in human subjects using this approach, which is currently under development. This represents perhaps one of the very few examples of an existing DNA-based therapy centered on an lncRNA system. Apart from cancer, H19 expression has been reported also in other conditions, syndromes and diseases, where deregulated imprinting at the H19 locus was obvious in some cases and will be summarized below. Moreover, the H19 locus proved to be much more complicated than initially thought. It houses a genomic sequence that can transcribe, yielding various transcriptional outputs, both in sense and antisense directions. The major transcriptional outputs of the H19 locus are presented here.

H19-promoter-targeted therapy combined with gemcitabine in the treatment of pancreatic cancer.

Pancreatic cancer is the eighth cancer leading cause of cancer-related death in the world and has a 5-year survival rate of 1-4% only. Gemcitabine is a first line agent for advanced pancreatic therapy; however, its efficacy is limited by its poor intracellular metabolism and chemoresistance. Studies have been conducted in an effort to improve gemcitabine treatment results by adding other chemotherapeutic agents, but none of them showed any significant advantage over gemcitabine monotherapy. We found that 85% of human pancreatic tumors analyzed by in situ hybridization analyses showed moderated to strong expression of the H19 gene. We designed a preclinical study combining gemcitabine treatment and a DNA-based therapy for pancreatic cancer using a non viral vector BC-819 (also known as DTA-H19), expressing the diphtheria toxin A chain under the control of the H19 gene regulatory sequences. The experiments conducted either in an orthotopic and heterotopic pancreatic carcinoma animal model showed better antitumor activity following the sequential administration of the vector BC-819 and gemcitabine as compared to the effect of each of them alone. The results presented in the current study indicate that treatment with BC-819 in combination with gemcitabine might be a viable new therapeutic option for patients with advanced pancreatic cancer.

Aerosolized BC-819 inhibits primary but not secondary lung cancer growth.

Despite numerous efforts, drug based treatments for patients suffering from lung cancer remains poor. As a promising alternative, we investigated the therapeutic potential of BC-819 for the treatment of lung cancer in mouse tumor models. BC-819 is a novel plasmid DNA which encodes for the A-fragment of Diphtheria toxin and has previously been shown to successfully inhibit tumor growth in human clinical study of bladder carcinoma. In a first set of experiments, we examined in vitro efficacy of BC-819 in human lung cancer cell-lines NCI-H460, NCI-H358 and A549, which revealed >90% reduction of cell growth. In vivo efficacy was examined in an orthotopic mouse xenograft lung cancer model and in a lung metastasis model using luminescent A549-C8-luc adenocarcinoma cells. These cells resulted in peri- and intra-bronchiolar tumors upon intrabronchial application and parenchymal tumors upon intravenous injection, respectively. Mice suffering from these lung tumors were treated with BC-819, complexed to branched polyethylenimine (PEI) and aerosolized to the mice once per week for a period of 10 weeks. Using this regimen, growth of intrabronchially induced lung tumors was significantly inhibited (p = 0.01), whereas no effect could be observed in mice suffering from lung metastasis. In summary, we suggest that aerosolized PEI/BC-819 is capable of reducing growth only in tumors arising from the luminal part of the airways and are therefore directly accessible for inhaled BC-819.

Transcriptional activation of a subset of hair keratin genes by the NF-kappaB effector p65/RelA.

The hair follicle is an intricate miniature organ dedicated to the production of the structural hair fiber, which is largely composed of hair keratin (HK) proteins. Many developmental pathways contribute to hair follicle development; however, the molecular control of HK genes is still far from being resolved. Because the nuclear factor (NF)-kappaB pathway is known to be involved in the morphogenesis of the hair follicle, we explored the possibility that it may also regulate HK expression. To this end, we analyzed the effect of p65/RelA, an NF-kappaB effector, on HK regulatory regions using transient transfections into tissue culture cells. Reporter assays on cells transfected with HK promoter constructs and real-time polymerase chain reaction analysis of endogenous HK gene activity demonstrated that p65 induces transcriptional activation of several HK genes of human and mouse origin, primarily that of acidic hair keratin 5 (Ha5). Focusing on the highly responsive human Ha5 gene, we defined the major NF-kappaB/RelA binding sites in its regulatory region and showed the direct binding of p65 to these sites using gel shift assays. We further show, using immunohistochemistry on human hair follicle sections, that p65 is co-expressed with HKs in the hair shaft compartment and may thus be the effector that mediates the NF-kappaB pathway's activity, which recently was genetically demonstrated to be active in the same region. Thus, we provide evidence for a previously unknown function of NF-kappaB in hair formation-direct activation of HK target genes-a function that may shed light on some of the symptoms of ectodermal dysplasias.