A modified γ-retrovirus vector for X-linked severe combined immunodeficiency.

BACKGROUND: In previous clinical trials involving children with X-linked severe combined immunodeficiency (SCID-X1), a Moloney murine leukemia virus-based γ-retrovirus vector expressing interleukin-2 receptor γ-chain (γc) complementary DNA successfully restored immunity in most patients but resulted in vector-induced leukemia through enhancer-mediated mutagenesis in 25% of patients. We assessed the efficacy and safety of a self-inactivating retrovirus for the treatment of SCID-X1. METHODS: We enrolled nine boys with SCID-X1 in parallel trials in Europe and the United States to evaluate treatment with a self-inactivating (SIN) γ-retrovirus vector containing deletions in viral enhancer sequences expressing γc (SIN-γc). RESULTS: All patients received bone marrow-derived CD34+ cells transduced with the SIN-γc vector, without preparative conditioning. After 12.1 to 38.7 months of follow-up, eight of the nine children were still alive. One patient died from an overwhelming adenoviral infection before reconstitution with genetically modified T cells. Of the remaining eight patients, seven had recovery of peripheral-blood T cells that were functional and led to resolution of infections. The patients remained healthy thereafter. The kinetics of CD3+ T-cell recovery was not significantly different from that observed in previous trials. Assessment of insertion sites in peripheral blood from patients in the current trial as compared with those in previous trials revealed significantly less clustering of insertion sites within LMO2, MECOM, and other lymphoid proto-oncogenes in our patients. CONCLUSIONS: This modified γ-retrovirus vector was found to retain efficacy in the treatment of SCID-X1. The long-term effect of this therapy on leukemogenesis remains unknown. (Funded by the National Institutes of Health and others; ClinicalTrials.gov numbers, NCT01410019, NCT01175239, and NCT01129544.).

CD8 T cell tolerance to a tumor-associated self-antigen is reversed by CD4 T cells engineered to express the same T cell receptor.

Ag receptors used for cancer immunotherapy are often directed against tumor-associated Ags also expressed in normal tissues. Targeting of such Ags can result in unwanted autoimmune attack of normal tissues or induction of tolerance in therapeutic T cells. We used a murine model to study the phenotype and function of T cells redirected against the murine double minute protein 2 (MDM2), a tumor-associated Ag that shows low expression in many normal tissues. Transfer of MDM2-TCR-engineered T cells into bone marrow chimeric mice revealed that Ag recognition in hematopoietic tissues maintained T cell function, whereas presentation of MDM2 in nonhematopoietic tissues caused reduced effector function. TCR-engineered CD8(+) T cells underwent rapid turnover, downmodulated CD8 expression, and lost cytotoxic function. We found that MDM2-TCR-engineered CD4(+) T cells provided help and restored cytotoxic function of CD8(+) T cells bearing the same TCR. Although the introduction of the CD8 coreceptor enhanced the ability of CD4(+) T cells to recognize MDM2 in vitro, the improved self-antigen recognition abolished their ability to provide helper function in vivo. The data indicate that the same class I-restricted TCR responsible for Ag recognition and tolerance induction in CD8(+) T cells can, in the absence of the CD8 coreceptor, elicit CD4 T cell help and partially reverse tolerance. Thus MHC class I-restricted CD4(+) T cells may enhance the efficacy of therapeutic TCR-engineered CD8(+) T cells and can be readily generated with the same TCR.

Novel highly specific anti-periostin antibodies uncover the functional importance of the fascilin 1-1 domain and highlight preferential expression of periostin in aggressive breast cancer.

Periostin (POSTN), a secreted homodimeric protein that binds integrins αvß3, αvß5, and α6ß4, was originally found to be expressed in fetal tissues and in the adult upon injury particularly bone fractures due to its role in remodelling and repair. Recently it was found to be over-expressed in human breast cancer and a variety of other tumour types including head and neck squamous cell carcinoma, where its overexpression correlates with increased tumour invasion. Progress in studying its functional role in tumour pathogenesis has been hampered by the paucity of antibodies for its specific and sensitive detection. It has proven very difficult to obtain monoclonal antibodies (mAbs) against this highly conserved protein but we report here that combining infection of mice with lactate dehydrogenase elevating virus (LDV), a B cell activating arterivirus, with conjugation of human POSTN to ovalbumin as an immunogenic carrier, enabled us to develop six mAbs recognizing both human and mouse POSTN and inhibiting its binding to αvß3 integrin. Two of the mAbs, MPB4B1 and MPC5B4, were tested and found to inhibit POSTN-induced migration of human endothelial colony forming cells. All six mAbs recognized amino acids 136-51 (APSNEAWDNLDSDIRR) within the POSTN fascilin (FAS) 1-1 domain revealing the functional importance of this motif; this was further highlighted by the ability of aa 136-151 peptide to inhibit integrin-mediated cell migration. Immunohistochemistry using MPC5B4, indicated that breast tumour cell POSTN expression was a strong prognostic indicator, along with tumour size, lymph node, and human epidermal growth factor receptor 2 (HER2) status.

Outcomes following gene therapy in patients with severe Wiskott-Aldrich syndrome.

IMPORTANCE: Wiskott-Aldrich syndrome is a rare primary immunodeficiency associated with severe microthrombocytopenia. Partially HLA antigen-matched allogeneic hematopoietic stem cell (HSC) transplantation is often curative but is associated with significant comorbidity. OBJECTIVE: To assess the outcomes and safety of autologous HSC gene therapy in Wiskott-Aldrich syndrome. DESIGN, SETTING, AND PARTICIPANTS: Gene-corrected autologous HSCs were infused in 7 consecutive patients with severe Wiskott-Aldrich syndrome lacking HLA antigen-matched related or unrelated HSC donors (age range, 0.8-15.5 years; mean, 7 years) following myeloablative conditioning. Patients were enrolled in France and England and treated between December 2010 and January 2014. Follow-up of patients in this intermediate analysis ranged from 9 to 42 months. INTERVENTION: A single infusion of gene-modified CD34+ cells with an advanced lentiviral vector. MAIN OUTCOMES AND MEASURES: Primary outcomes were improvement at 24 months in eczema, frequency and severity of infections, bleeding tendency, and autoimmunity and reduction in disease-related days of hospitalization. Secondary outcomes were improvement in immunological and hematological characteristics and evidence of safety through vector integration analysis. RESULTS: Six of the 7 patients were alive at the time of last follow-up (mean and median follow-up, 28 months and 27 months, respectively) and showed sustained clinical benefit. One patient died 7 months after treatment of preexisting drug-resistant herpes virus infection. Eczema and susceptibility to infections resolved in all 6 patients. Autoimmunity improved in 5 of 5 patients. No severe bleeding episodes were recorded after treatment, and at last follow-up, all 6 surviving patients were free of blood product support and thrombopoietic agonists. Hospitalization days were reduced from a median of 25 days during the 2 years before treatment to a median of 0 days during the 2 years after treatment. All 6 surviving patients exhibited high-level, stable engraftment of functionally corrected lymphoid cells. The degree of myeloid cell engraftment and of platelet reconstitution correlated with the dose of gene-corrected cells administered. No evidence of vector-related toxicity was observed clinically or by molecular analysis. CONCLUSIONS AND RELEVANCE: This study demonstrated the feasibility of the use of gene therapy in patients with Wiskott-Aldrich syndrome. Controlled trials with larger numbers of patients are necessary to assess long-term outcomes and safety.

Diagnostic and molecular aspects of adrenal cortical tumors.

Adrenal cortical diseases are relatively rare but tumors are the most common in diagnostic practice. This is reflected by the content of this review. By studying familial syndromes in which they occur more frequently and the pathways involved in steroidogenesis and cortical growth, the molecular genetics of these tumors is being unraveled. Genome-wide approaches have also been helpful. The emerging data may complement standard histological investigation in diagnosis and prognosis.

Update on tumours of the adrenal cortex, phaeochromocytoma and extra-adrenal paraganglioma.

This review covers aspects of adrenal cortical tumours, phaeochromocytoma and extra-adrenal paragangliomas. Relevant clinical and epidemiological information is included. It is now known that about 30% of paragangliomas occur in a familial setting and these new aspects of the genetic background are presented. The main diagnostic problem in both groups of tumours is the recognition of malignant potential. The uses and limitations of multifactorial histological assessment in diagnosis and prognosis are discussed. Finally, data on the molecular changes associated with tumorigenesis and tumour progression are highlighted, and how this information may contribute in future to diagnosis and prognosis.

A diagnostic approach to adrenal cortical lesions.

The adrenal gland is not a common specimen in surgical pathology practice as, until recently, adrenal tumors were recognized in life only if associated with hypersecretion of hormones or evidence of malignancy. However, adrenal nodules are not uncommon at autopsy, and the number of these found in life is now increasing as they are identified when the abdomen is scanned for the investigation of other diseases using computed tomography or magnetic resonance imaging. It is therefore becoming increasingly important for the surgical pathologist to be aware of the range of pathology in the gland and to understand how to approach the specimens. This short review will deal with lesions of the adrenal cortex.

Pathology of pheochromocytoma and extra-adrenal paraganglioma.

The 2004 WHO classification of endocrine tumors defines pheochromocytoma as a tumor arising from chromaffin cells in the adrenal medulla. Closely related tumors in extra-adrenal sympathetic and parasympathetic paraganglia are classified as extra-adrenal paragangliomas. A pheochromocytoma is an intra-adrenal sympathetic paraganglioma. While arbitrary, this nomenclature serves to emphasize important distinctive properties of intra-adrenal tumors that must be taken into account in clinical practice and research. Those include an often adrenergic phenotype, a relatively low rate of malignancy, and a predilection to occur in particular hereditary syndromes. Current roles of pathology are limited to distinguishing primary or metastatic pheochromocytomas/paragangliomas from other endocrine or nonendocrine tumors, and flagging tumors that show features suggestive of malignant potential or syndromic disease. Future roles may involve more definitive assessment of malignancy, genotype-phenotype correlation, and identification of targets for therapy. Pathology practice currently rests mostly on interpretation of conventional histological sections stained with hematoxylin and eosin, with variable ancillary application of immunohistochemical staining. Malignancy is currently defined by the presence of metastases, not local invasion. Local invasion alone is a poor predictor of metastases, and the absence of apparent invasion does not preclude development of metastases. The two types of aggressive behavior might therefore have different biological underpinnings, and those will be resolved most effectively if consistent terminology is employed. In order to be optimally informative, pathology reports must employ consistent nomenclature and incorporate standard elements. Templates or checklists for minimal standard reporting are recommended by several pathology associations, but identification of some recommended and optional elements is currently subjective or inconsistent.

Assessment of malignancy in adrenal cortical tumors.

The roles of the pathologist in assessing adrenal cortical tumors are, first, to differentiate adenoma from carcinoma, and, second, to assess prognosis when the diagnosis of malignancy is made. How easy is it to achieve these goals with standard histology and immunohistochemistry, and to what extent can molecular analysis help?

Histopathology and immunohistochemistry of adrenal medullary tumors and paragangliomas.

Paragangliomas arise from sympathetic or parasympathetic paraganglia and should now be defined by their site and type. The term pheochromocytoma is reserved for intra-adrenal tumors. This short review discusses the gross and microscopic features, the immunohistochemical profile, the problem of recognizing malignant potential, and the rare instances where a differential diagnosis has to be considered.

SASH1 mediates sensitivity of breast cancer cells to chloropyramine and is associated with prognosis in breast cancer.

Expression of the SASH1 protein is reduced in a range of human cancers and has been implicated in apoptotic cancer cell death. This study investigated whether increasing SASH1 expression could be a useful therapeutic strategy in breast cancer. Ectopic SASH1 expression increased apoptosis in 7/8 breast cancer cell lines. Subsequent in silico connectivity screening demonstrated that the clinically approved antihistamine drug, chloropyramine, increased SASH1 mRNA levels. Chloropyramine has previously been shown to have anti-tumour activity in breast cancer in part through modulation of FAK signalling, a pathway also regulated by SASH1. This study demonstrated that chloropyramine increased SASH1 protein levels in breast cancer cells. Consistent with this the agent reduced cell confluency in 7/8 cell lines treated irrespective of their ER status but not apoptosis incompetent MCF7 cells. In contrast SASH1 siRNA-transfected breast cancer cells exhibited reduced chloropyramine sensitivity. The prognostic significance of SASH1 expression was also investigated in two breast cancer cohorts. Expression was associated with favourable outcome in ER-positive cases, but only those of low histological grade/proliferative status. Conversely, we found a very strong inverse association in HER2+ disease irrespective of ER status, and in triple-negative, basal-like cases. Overall, the data suggest that SASH1 is prognostic in breast cancer and could have subtype-dependent effects on breast cancer progression. Pharmacologic induction of SASH1 by chloropyramine treatment of breast cancer warrants further preclinical and clinical investigation.

Identification of adrenocorticotropin receptor messenger ribonucleic acid in the human pituitary and its loss of expression in pituitary adenomas.

The ACTH receptor (ACTH-R) is the second member of the melanocortin (MC-2) receptor family that includes five seven-transmembrane G protein-coupled receptors and has been shown to be predominantly expressed in the adrenal cortex. It has been postulated that ACTH may regulate its own secretion through ultra-short-loop feedback within the pituitary. ACTH-secreting adenomas are characterized by resistance to glucocorticoid feedback, and they may have dysregulated ACTH feedback. We therefore investigated the ACTH-R in normal and adenomatous human pituitary tissue. We report here the identification of ACTH-R mRNA in the human pituitary gland, which was confirmed by direct sequencing. We studied the expression of the ACTH-R in 23 normal pituitary specimens and 53 pituitary adenomas (22 ACTH-secreting, nine GH-secreting, eight prolactin-secreting, one TSH-secreting, one FSH-secreting, 10 nonfunctioning, and two silent corticotroph adenomas), using the sensitive technique of real-time quantitative PCR. Contamination of ACTH-secreting adenomas and nonfunctioning pituitary adenomas with nonadenomatous tissue was excluded by lack of Pit-1 expression. ACTH-R mRNA was detected in all normal pituitary specimens, and in situ hybridization colocalized expression to ACTH staining cells only. However, ACTH-R mRNA levels were undetectable in 16 of 22 ACTH-secreting tumors and in both silent corticotroph tumors. Diagnostic preoperative plasma ACTH levels were significantly lower in the ACTH-R positive ACTH-secreting tumors, compared with those who were ACTH-R negative (P = 0.0006). Direct sequencing of the coding region of the ACTH-R in cDNA from three ACTH-secreting tumors positively expressing the receptor showed no mutations, as did sequencing of genomic DNA in three receptor negative ACTH-secreting tumors and the two silent corticotrophs. These results provide further evidence compatible with an ACTH feedback loop in the pituitary and suggest that loss of expression of the ACTH-R in corticotroph adenomas of patients with Cushing's disease may play a role in the resistance to feedback of the pituitary-adrenal axis seen in these patients.

Adrenal cortical diseases: international case conference.

Six pathologists from Japan and the United Kingdom evaluated four different cases of adrenocortical disorders independently. These adrenocortical disorders included an adrenal tumor in a 45-yr-old female without any endocrine abnormalities, bilateral adrenocortical lesions in a 55-yr-old female with Cushing syndrome, an adrenocortical mass in a 44-yr-old man with hypertension, and an adrenocortical lesion in a 62-yr-old female with chronic hypertension for 30 yr. In this article, we provide a clinical summary, macroscopic and histologic findings, and histologic diagnosis of these four adrenocortical cases.

Pathology of the adrenal cortex: a reappraisal of the past 25 years focusing on adrenal cortical tumors.

A reappraisal of the major advances in the diagnostic pathology of adrenal cortical lesions and tumors in the last 25 years is presented, with special reference to the definition of malignancy in primary adrenal cancer and its variants. Slightly more than 25 years ago, Weiss proposed his diagnostic scoring system for adrenal cortical carcinoma. This represented a milestone for adrenal pathologists and the starting point for further modifications of the system, either through minor changes in the scoring procedure itself or concentrating on some particular Weiss criterion such as mitotic index, integrated into alternative scoring schemes or algorithms that are currently under validation. Improvements in diagnostic immunohistochemistry have led to the identification of markers of cortical origin, such as Melan-A, alpha-inhibin, and SF-1 and of prognostic factors in carcinoma, such as the Ki-67 proliferation index and SF-1 itself. With regard to hyperplastic conditions, genetic investigations have allowed the association of the majority of cases of primary pigmented nodular adrenocortical disease (PPNAD) in Carney complex to mutations in the gene encoding the regulatory subunit 1A of protein kinase A (PRKAR1A). Other hereditary conditions are also associated with adrenal cortical tumors, including the Li-Fraumeni, Beckwith-Wiedemann, Gardner, multiple endocrine neoplasia type 1, and neurofibromatosis type 1 syndromes. Moreover, several advances have been made in the knowledge of the molecular background of sporadic tumors, and a number of molecules/genes are of particular interest as potential diagnostic and prognostic biomarkers.

Protocol for the examination of specimens from patients with pheochromocytomas and extra-adrenal paragangliomas.

During the last decade there have been revolutionary breakthroughs in understanding the biology of pheochromocytomas and extra-adrenal paragangliomas. Discoveries of new susceptibility genes and genotype-phenotype correlations have led to the realization that appropriate patient care requires a complete integration of clinical, genetic, biochemical, imaging, and pathology findings. Clinical practice has in many cases not kept pace with the rate of discovery, underscoring a need for updated procedures for evaluation of patient specimens and reporting of data. We therefore propose a new synoptic reporting approach for pheochromocytomas and extra-adrenal paragangliomas that will provide clear and uniform information to pathologists and clinicians, in order to advance the diagnosis of these neoplasms and optimize patient care.

Phase I study protocol for ex-vivo lentiviral gene therapy for the inherited skin disease, Netherton Syndrome.

Netherton syndrome (NS) is a serious inherited skin disorder caused by mutations in the gene SPINK5 (serine protease inhibitor Kazal type 5) which encodes for a serine protease inhibitor LEKTI (lymphoepithelial Kazal type-related inhibitor). Patients with NS have defective keratinization, hair shaft defects, recurrent infections, atopy and a predisposition to skin malignancies. Historically, one in ten infants has died before their first birthday. Currently there are no proven treatments to cure this condition. A SIN-lentiviral vector encoding the codon optimized SPINK5 gene under the control of a 572bp element derived from the human involucrin promoter (INVO) can confer compartment specific LEKTI expression in NS keratinocytes with restoration of normal skin architecture. Here we detail a study protocol for a phase I trial for feasibility and safety evaluations of autologous epidermal sheets generated from ex-vivo gene corrected keratinocyte stem cells, which will be grafted onto patients with mutation proven NS.

Production and first-in-man use of T cells engineered to express a HSVTK-CD34 sort-suicide gene.

UNLABELLED: Suicide gene modified donor T cells can improve immune reconstitution after allogeneic haematopoietic stem cell transplantation (SCT), but can be eliminated in the event of graft versus host disease (GVHD) through the administration of prodrug. Here we report the production and first-in-man use of mismatched donor T cells modified with a gamma-retroviral vector expressing a herpes simplex thymidine kinase (HSVTK):truncated CD34 (tCD34) suicide gene/magnetic selection marker protein. A stable packaging cell line was established to produce clinical grade vector pseudotyped with the Gibbon Ape Leukaemia Virus (GALV). T cells were transduced in a closed bag system following activation with anti-CD3/CD28 beads, and enriched on the basis of CD34 expression. Engineered cells were administered in two escalating doses to three children receiving T-depleted, CD34 stem cell selected, mismatched allogeneic grafts. All patients had pre-existing viral infections and received chemotherapy conditioning without serotherapy. In all three subjects cell therapy was tolerated without acute toxicity or the development of acute GVHD. Circulating gene modified T cells were detectable by flow cytometry and by molecular tracking in all three subjects. There was resolution of virus infections, concordant with detectable antigen-specific T cell responses and gene modified cells persisted for over 12 months. These findings highlight the suitability of tCD34 as a GMP compliant selection marker and demonstrate the feasibility, safety and immunological potential of HSVTK-tCD34 suicide gene modified donor T cells. TRIAL REGISTRATION: ClinicalTrials.gov NCT01204502

Phase I study protocol for ex vivo lentiviral gene therapy for the inherited skin disease, Netherton syndrome.

Netherton syndrome (NS) is a serious inherited skin disorder caused by mutations in the serine protease inhibitor Kazal type 5 gene (SPINK5), which encodes for a serine protease inhibitor lymphoepithelial Kazal type-related inhibitor (LEKTI). Patients with NS have defective keratinization, hair shaft defects, recurrent infections, atopy, and a predisposition to skin malignancies. Historically, 1 in 10 infants has died before their first birthday. Currently, there are no proven treatments to cure this condition. A SIN-lentiviral vector encoding the codon-optimized SPINK5 gene under the control of a 572 bp element derived from the human involucrin promoter can confer compartment-specific LEKTI expression in NS keratinocytes with restoration of normal skin architecture. Here we detail a study protocol for a phase I trial for feasibility and safety evaluations of autologous epidermal sheets generated from ex vivo gene-corrected keratinocyte stem cells, which will be grafted onto patients with mutation-proven NS.