Systemic involvement in adult-onset leukoencephalopathy with intracranial calcifications and cysts (Labrune syndrome) with a novel mutation of the SNORD118 gene.

BACKGROUND AND PURPOSE: Although Labrune syndrome is a well-known disorder characterized by a typical neuroradiological triad, namely leukoencephalopathy, intracranial calcifications and cysts, there are no reports of systemic involvement in this disorder. This paper attempts to describe a peculiar clinical manifestation related to a novel mutation in the SNORD118 gene. METHODS: Clinical examination, brain and total-body imaging, and neurophysiological and ophthalmological investigations were performed. Amplification of the SNORD118 gene and Sanger sequencing were integrated to investigate potential causative mutations. RESULTS: A 69-year-old woman, with a long history of episodes of vertigo and gait imbalance, was referred to our hospital for progressive cognitive and motor deterioration. Computed tomography and magnetic resonance imaging disclosed diffuse bilateral leukoencephalopathy in periventricular and deep white matter, widespread calcifications and numerous cysts in the brain, liver, pancreas and kidneys. The genetic analysis revealed two biallelic variants in the SNORD118 gene, one of which is novel (n.60G>C). CONCLUSIONS: This is the first report of adult-onset Labrune syndrome with an unusual systemic involvement presenting a novel mutation in the SNORD118 gene.

beta2-Microglobulin mutations, HLA class I antigen loss, and tumor progression in melanoma.

The potential negative impact of HLA class I antigen abnormalities on the outcome of T cell-based immunotherapy of melanoma has prompted us to investigate the mechanisms underlying lack of HLA class I antigen expression by melanoma cell lines Me18105, Me9923, and Me1386. Distinct mutations in the beta2-microglobulin (beta2m) gene were identified in each cell line which result in loss of functional beta2m. In Me18105 cells, an aberrant splicing mechanism caused by an A--> G point mutation in the splice acceptor site of intron 1 of the beta2m gene, deletes 11 bp from the beta2m mRNA creating a shift in the reading frame. In Me9923 cells a 14-bp deletion in exon 2 and in Me1386 cells a CT deletion in exon 1 of the beta2m gene produce a frameshift mutation. The beta2m gene mutations identified in Me18105, Me9923, and Me1386 cells were also detected in the surgically removed melanoma lesions from which the cell lines originated. Transfection of each melanoma cell line with a wild-type beta2m gene restored HLA class I antigen expression and, in Me18105 cells, recognition by Melan-A/MART-1-specific, HLA-A2-restricted cytotoxic T lymphocytes. Interestingly, the beta2m mutation present in Me9923 cells that were derived from a metastatic lesion was also found in the Me9923P cell line that originated from the autologous primary lesion. These data suggest that beta2m mutations in melanoma cells may be an early event in progression to the malignant phenotype.

Regression of advanced ovarian carcinoma by intraperitoneal treatment with autologous T lymphocytes retargeted by a bispecific monoclonal antibody.

BACKGROUND: The high frequency of relapse after induction chemotherapy of advanced ovarian carcinoma calls for new therapeutic approaches. Lysis of ovarian carcinoma cells can be achieved by retargeting of T lymphocytes using F(ab')2 fragments of the bispecific monoclonal antibody (MAb) OC/TR, which is directed to the CD3 molecule on T lymphocytes and to the folate receptor on ovarian carcinoma cells. PURPOSE: Our purpose was to assess in ovarian carcinoma patients the antitumor activity of in vitro-activated autologous peripheral blood T lymphocytes retargeted with OC/TR. METHODS: Patients with epithelial ovarian cancer (International Federation of Gynecology and Obstetrics stages III and IV) meeting specific criteria were eligible to enter a phase II immunotherapy trial. Before immunotherapy, the 28 patients who entered the trial underwent laparotomy to reduce their tumor load and to allow measurement of all indicator lesions. They then received two cycles of five daily intraperitoneal infusions of autologous in vitro activated peripheral blood T lymphocytes retargeted with OC/TR plus recombinant interleukin 2 (IL-2) with (n = 11) or without (n = 17) a second daily infusion of OC/TR F(ab')2 and IL-2. Response to treatment could be assessed in 26 patients following explorative laparotomy; time to progression could be assessed in 27 patients. RESULTS: Seven patients had clinical evidence of progressive disease after treatment and therefore did not undergo laparotomy. Of the 19 patients evaluated by surgery and histology, three showed complete response, one showed complete intraperitoneal response with progressive disease in retroperitoneal lymph nodes, three showed partial response, seven had stable disease, and five had progressive disease. The overall intraperitoneal response rate was 27% (95% confidence interval [CI] = 10%-44%). The complete responses seen in three patients lasted 26 months in one patient, 23 months in the second, and 18 months in the third. Two patients were not assessable for response. One of these patients had bowel perforation during catheter removal, which precluded further evaluation. The second patient was positive only by cytologic examination before immunotherapy, was tumor free at laparotomy after immunotherapy, and remained so for the entire 21 months of follow-up, as determined by cytologic examination of random biopsy specimens. The median time to disease progression in the 15 assessable patients plus those who had stable disease was 11 months (95% CI = 6-18 months). Immunotherapy-related toxic effects included mild to moderate fever, nausea, emesis, and fatigue. Anti-mouse antibodies were detectable by the end of the treatment in 21 of 25 patients tested. CONCLUSIONS: Locoregional immunotherapy of ovarian cancer with bispecific MAb-retargeted T lymphocytes can result in tumor regression. Toxicity was mild to moderate and only transient. IMPLICATIONS: Improvement in systemic antitumor responses is needed before this approach can prove useful as adjunctive treatment following induction chemotherapy in patients with minimal residual disease.

Overexpression of the T-cell receptor beta-chain variable region TCRBV14 in HLA-A2-matched primary human melanomas.

We have shown previously that peripheral blood lymphocytes (PBL) of patients with metastatic melanoma include cytotoxic T-cell clones that recognize Melan-A/MART-1 in a HLA-A2-restricted fashion. Such clones preferentially use the variable (V) regions TCRBV14 or TCRBV7 in the beta-chain of their T-cell receptor (TCRB). It was not known, however, whether this finding is associated with the presence of the HLA-A2 allele in tumor tissue and whether evidence of the predominance of these TCRBV families can also be observed in primary tumor tissue. To address these issues, we have used a semiquantitative PCR to examine the TCRBV repertoire in six HLA-A2-matched primary melanomas in comparison with their autologous PBL. Although each patient had his or her own pattern of skewed TCRBV utilization, in all patients, T-cells that used TCRBV14 were significantly overrepresented in the neoplastic site compared with PBL. All of the primary tumors studied had detectable expression of Melan-A/MART-1 and gp100, and immunohistochemical analysis confirmed the presence of the HLA-A2 allele. Additional samples of Melan-A/MART-1-positive, gp100-positive primary melanomas from six non-HLA-A2 patients and four autologous normal skin controls failed to reveal a TCRBV14 predominance in such tissues. These results point to a role of TCRBV14 T lymphocytes in the HLA-A2-restricted immune recognition of primary melanomas.

Recognition of melanoma-derived antigens by CTL: possible mechanisms involved in down-regulating anti-tumor T-cell reactivity.

Several T cell-recognized epitopes presented by melanoma cells have been identified recently. Despite the large array of epitopes potentially available for clinical use, it is still unclear which of these antigens could be effective in mediating anti-tumor responses when used as a vaccine. Preliminary studies showed that immunization of melanoma patients with epitopes derived from proteins of the MAGE family may result in significant clinical regressions. However, no sign of systemic immunization could be observed in peripheral blood of treated patients. Conversely, significant immunization (detected as increased antigen-specific CTL activity in peripheral blood) was obtained by vaccinating HLA-A2.1+ melanoma patients with the immunodominant epitope (residues 27-35) of the differentiation antigen MART-1, but this immunization was not accompanied by a significant clinical response. To implement immunotherapeuties capable of significantly impacting disease outcome, it is necessary to identify the potential mechanisms responsible for the failure of some antigens to mediate significant anti-tumor responses in vivo. In the case of the MART-1(27-35) epitope, we hypothesize that one of these mechanisms may be related to the existence of natural analogs of this peptide in other human normal proteins.

A human melanoma cell line transduced with an interleukin-4 gene by a retroviral vector releases biologically active IL-4 and maintains the original tumor antigenic phenotype.

Experimental models of vaccination with tumor cells engineered to produce interleukin-4 (IL-4) have shown that the local release of this cytokine is associated with the development of antitumor immunity that may induce regression of established cancer. The aim of this study was to transduce a human melanoma cell line with the gene coding for human IL-4, and to analyze cytokine production, phenotypic characteristics, and antigen expression after transduction. A retroviral vector, constructed by inserting IL-4 cDNA into the LXSN vector, was used to infect the human melanoma cell line Me14932, known to express the MHC class I HLA-A2 and the melanoma-associated antigen Melan-A/MART-1, recognized by HLA-A2-restricted T-cells. The confluence of all G418-resistant cells (Me14932/IL-4) was then analyzed for proviral integration and IL-4 mRNA expression. Substantially stable IL-4 release was detected by ELISA in the supernatant of transduced cells, ranging from 1.6 to 4.6 ng/ml per 10(5) cells per 24 hr; such a cytokine displayed a specific biologic activity, as revealed by the stimulation of blast cell proliferation and the inhibition of lymphokine activated killer cell (LAK) induction by IL-2. After 200 Gy irradiation, IL-4 release remained detectable for 5 weeks, whereas cell proliferation ceased within 7 days. Morphology and immunophenotypic characteristics of the parental cell line (expression of MHC classes I and II, ICAM-1, LFA 3, melanoma-associated antigens, etc.) were retained by the IL-4 gene-transduced melanoma as assayed by microscopy and immunofluorescence; likewise, susceptibility to lysis by LAK cells as well as a T-cell clone recognizing the Melan-A/MART-1 antigen did not change. These results, together with the lack of replication-competent retrovirus, suggest that the Me14932/IL-4 cell line displays suitable characteristics for its use in the treatment of HLA-matched melanoma patients.

Interleukin-2 gene-transduced human melanoma cells efficiently stimulate MHC-unrestricted and MHC-restricted autologous lymphocytes.

Two human melanoma lines were transduced by a retroviral vector with the gene of the human interleukin-2 (IL-2) and characterized for their immunological properties in comparison with the parental lines. Transduction resulted in the production of biologically active IL-2 in the average amounts of 2,282 and 2,336 pg/ml per 10(5) cells per 24 hr over 3 and 2 months by the Me14932/IL-2 and the Me1B6/IL-2 lines, respectively. Melanoma-transduced cells lost their tumorigenicity in nude mice. No major changes in the phenotype were observed in IL-2 gene-transduced lines. In fact, more than 90% of cells expressed class I and II(DR) HLA, adhesion molecules, integrins, and melanoma-associated antigens. Irradiation with 100-400 Gy, while inhibiting tumor cell growth in vitro, allowed the release of IL-2 by the transduced cells for at least 5 weeks. The two melanoma lines also maintained susceptibility to lysis by lymphokine-activated killer (LAK) cells and by a HLA-A2-restricted melanoma-specific cytotoxic T lymphocyte (CTL) clone recognizing the melanoma antigen (Melan-A). In a limiting dilution assay, transduced, but not parental melanoma lines unless added with an amount of IL-2 comparable to that released by the transduced cells, were able to expand both nonspecific and melanoma-specific CTL precursors from autologous peripheral blood lymphocytes (PBL). In mixed lymphocytes-tumor cultures, IL-2 gene-transduced melanoma cells stimulated the expansion of major histocompatibility complex (MHC)-unrestricted effectors from autologous PBL, and of CD3+ CD8+ MHC-restricted CTL from tumor-invaded lymph nodes. These results indicate that IL-2 gene transduction does not alter significantly the expression of the immunologically relevant molecules of human melanoma lines while increasing their ability to stimulate both specific and nonspecific lymphocyte responses. These lines will be of value in the vaccination of melanoma patients.

Limited antitumor T cell response in melanoma patients vaccinated with interleukin-2 gene-transduced allogeneic melanoma cells.

We have immunized advanced melanoma patients with a HLA-A2-compatible human melanoma line genetically modified to release interleukin-2 (IL-2), to elicit or increase a T cell-mediated anti-melanoma response that may affect distant lesions. Twelve stage-IV patients were injected subcutaneously at days 1, 13, 26, and 55 with IL-2 gene-transduced and irradiated melanoma cells at doses of 5 or 15 x 10(7) cells. Both local and systemic toxicities were mild, consisting of transient erythema at the vaccination site; fever occurred in a minority of patients. Three mixed responses were recorded. Seven patients were evaluable for immunological studies. Mixed tumor-lymphocyte cultures carried out with different allogeneic HLA-A2-matched melanoma lines as stimulators and targets revealed an increase in the MHC-unrestricted, but no changes in the MHC-restricted, cytotoxicity in peripheral blood lymphocytes (PBL) obtained after vaccination as compared with those obtained before vaccination. Increased recognition of the tyrosinase 368-376 peptide occurred in post-vaccination PBL of one patient, whereas a weak increase in recognition of the gp100 280-288 peptide was detectable in another patient; these 2 patients also recognized the gp100 457-466 peptide. After in vitro, stimulation with the only available autologous melanoma line, CD4+ cells with autologous tumor-specific cytotoxicity and ability to release interferon-gamma (IFN-gamma) were found in post- but not in pre-vaccination PBL. In the same patient, as well as in another patient, limiting dilution analysis showed that vaccination resulted in an increased frequency of melanoma-specific cytotoxic T lymphocyte (CTL) precursors. These results indicate that vaccination with cells releasing IL-2 locally can expand a T cell response against antigen(s) of autologous, untransduced tumor, although this response occurred in a minority of the melanoma patients studied.

Vaccination of melanoma patients with interleukin 4 gene-transduced allogeneic melanoma cells.

A human melanoma line genetically modified to release interleukin 4 (IL-4) was utilized to immunize advanced melanoma patients in order to elicit or increase a specific anti-melanoma immune response, which may affect distant lesions. Twelve metastatic melanoma patients were injected subcutaneously at least three times with 5 x 10(7) IL-4 gene-transduced and irradiated allogeneic melanoma cells per dose. Both systemic and local toxicities were mild, consisting of transient fever and erythema, swelling, and induration at the vaccination site. Two mixed but not complete or partial clinical responses were recorded. To assess the immune response of vaccinated patients, both serological and cell-mediated activities were evaluated. Antibodies to alloantigens could be detected in 2 of 11 patients tested. Mixed tumor-lymphocyte cultures were performed, utilizing autologous and allogeneic HLA-A2-matched melanoma lines as simulators and targets. A significant increase in IFN-gamma release was detected in 7 of 11 cases when postvaccination lymphocytes were stimulated by the untransduced allomelanoma cells. However, induction of a specific recognition of autologous melanoma cells by PBLs was obtained after vaccination in only one of six cases studied. This response involved the melanoma peptide Melan-A/MART-1(27-35) that was recognized in an HLA-A2-restricted fashion. These results indicate that vaccination with allogeneic melanoma cells releasing IL-4 locally can expand a T cell response against antigen(s) of autologous, untransduced tumor, although in a minority of patients.

Neuropsychological and neurophysiological assessment of the central effects of interleukin-2 administration.

Neuropsychiatric disturbances may occur following interleukin-2 (IL2) administration. We studied the effects of IL2 infusion on cerebral functions in 7 patients with neuropsychological tests and event-related evoked potentials (P300). We observed a failure in the cognitive performances, an increase in latency, and a decrease in amplitude of P300. These effects followed IL2 administration and were reversible.

Treatment of recurrent in transit metastases from cutaneous melanoma by isolation perfusion in extracorporeal circulation with interleukin-2 and lymphokine activated killer cells. A pilot study.

Chemoresistant melanoma cells are known to be susceptible in vitro to lymphokine activated killer (LAK) cells. To obtain a high LAK/tumour cell ratio in vivo and avoid systemic toxicity due to interleukin-2 (IL-2), we used IL-2 plus LAK cells in the treatment of in transit melanoma metastases of the limbs by isolation perfusion (IP). In vivo immunological modifications induced by this immunotherapeutic approach were also analysed. Six patients previously treated with IP in extracorporeal circulation with tumour cytotoxic drugs and presently relapsing or not responding, were submitted to locoregional adoptive therapy consisting of 5 days systemic administration of IL-2 (Proleukin, EuroCetus) (9-12 x 10(6) IU/m2/day c.i.). Autologous LAK cells were derived from leukapheresis and subsequent in vitro stimulation with IL-2; LAK cells were then given along with IL-2 (120-2400 IU/ml of perfusion priming) to the affected limb by IP. In addition, 7-16 x 10(9) LAK cells were administered by systemic infusion the day after together with IL-2 (9-12 x 10(6) IU/m2/day) by c.i. for 5 days. All patients concluded the treatment without major toxicity. The analysis of circulating lymphocytes obtained from extracorporeal circuit at different times revealed rapid disappearance of LAK cells, suggesting their extravasation and/or endothelial adhesion in perfused tissues. Clinical responses included four partial and one complete response; another patient had stable disease. All patients are presently alive. Follow-up after IP ranges from 8 to 22 months.

CEA and NCA expressed by colon carcinoma cells affect their interaction with and lysability by activated lymphocytes.

Heterogeneous lysability by interleukin-2 activated lymphocytes (LAK) and other immune effectors was observed in the human colon-carcinoma lines LoVo/Dx, LoVo/H and HT29. The tumor cells with high susceptibility to LAK (LoVo/Dx, HT29) expressed higher amounts of the adhesion molecules ICAMl, LFA3 and NCA/CEA than cells with low LAK sensitivity (LoVo/H). Monoclonal antibodies against these molecules caused a marked reduction of lysis by LAK of LoVo/Dx and HT29. A pool of these antibodies induced a nearly complete inhibition of the LAK lysis of both lines. Treatment of LoVo/Dx with differentiating agents (dimethylformamide and retinoic acid) led to a decreased expression of the adhesion molecules, including NCA, accompanied by increased resistance to LAK-mediated lysis. Moreover, the presence of CEA soluble antigen drastically inhibited the cytotoxic activity of LAK effectors against HT29 and LoVo/Dx cells, in a dose-dependent manner. These data indicate that sensitivity of colon-carcinoma cells to activated lymphocytes depends on the level of expression of adhesion molecules, including CEA and NCA. Given the role of CEA-related antigens in tumor/lymphocyte interaction, soluble CEA, frequently released by colon-carcinoma, may be involved in immunosuppressive effects induced in vivo by tumor cells.

Chronic effects of subcutaneous interleukin-2 therapy on soluble interleukin-2 receptors in advanced small cell lung cancer.

The increase in IL-2 receptor serum levels is one of the most typical changes in immune parameters during IL-2 cancer immunotherapy. To better define the effects of prolonged IL-2 injection on SIL-2R levels, we evaluated 7 advanced small cell lung cancer patients who received IL-2 subcutaneously at a daily dose of 9 x 10(6) IU/m2/12h for two days followed by 3 x 10(6) IU/m2/12h for 18 days (5 days/week for 4 weeks). Moreover, four patients were also evaluated during the second IL-2 cycle. Venous blood samples were drawn before and at weekly intervals during IL-2 therapy. Mean SIL-2R serum levels rapidly increased with the start of IL-2 injection, and they were significantly higher than the baseline levels throughout the immunotherapy cycle. The increase in mean SIL-2R levels was higher in patients with progressive disease than in those with response or stable disease, but the difference was not significant. Finally, the increase in mean SIL-2R concentrations during the second IL-2 cycle was not significantly different from that seen during the first one. The present study confirms that IL-2 administration determines an evident increase in SIL-2R levels; moreover, it would demonstrate that re-exposure to IL-2 after a rest period does not induce a more pronounced SIL-2R release.

Gene therapy in melanoma.

The identification of genes involved in different biologic functions and in the pathogenesis of diseases has paved the way to the possibility of either interfering with the role of such genes or replacing them in somatic cells in case of loss, which may occur in some genetic diseases or cancer. Such progress has been accomplished thanks to advances in molecular biology and applied technology that allow the transport and insertion of genes into recipient cells by viral or physical vectors as well as the inhibition of gene transcription by antisense oligonucleotides. Methods have also been devised to transfer genes not only in vitro but also in vivo, although this latter approach is still limited owing to poor selectivity and targeting of most vectors when given systemically. Viral and physical vectors have been employed; each of these vectors has distinct advantages and disadvantages, and, therefore, the appropriate vector should be selected according to the therapeutic system involved (1). Retro viral vectors have been used largely for their ability to selectively transfect proliferating cells, a feature that can be advantageous in case one wishes to target only proliferating tumor cells. Owing to the heterogeneous proliferation rate in different parts of a tumor, however, it could be desirable, under some circumstances, to be able to target even the fraction of nonproliferating tumor cells. This can now be obtained by the use of lentivirus (2) or by switching to the use of adenoviruses that can target both dividing and quiescent cells but also induce unwanted inflammmatory reactions from the host.

Cytokine-based gene therapy of human tumors. An overview.

This review first summarizes the different strategies of gene therapy of cancer and then focuses on the immunological approach. Several studies in animal models with cytokine gene-transduced tumor cells indicate that local cytokine release usually results in tumor growth inhibition. Moreover, in a number of cases vaccination with such cells can reduce growth of established tumors or even cure the tumor-bearing animals. Translation of such a principle in human clinical setting is reported. We have transduced human melanoma cells with genes coding for interleukin (IL)-2, IL-4 or B7-1 and characterized such lines. The phenotype did not change after gene insertion but the functional, immunostimulatory activity of IL-2 or B7-1 gene-transduced melanoma cells was significantly increased compared to that of parental lines. These-lines were then used to vaccinate melanoma patients. Preliminary results of trials with IL-2 gene-transduced cells are presented which indicate a weak clinical response and the activation of a melanoma-specific cytotoxic T lymphocyte response in a low percentage of patients.

Effect of prolonged subcutaneous administration of interleukin-2 on the circadian rhythms of cortisol and beta-endorphin in advanced small cell lung cancer patients.

Interleukin-2 has been shown to stimulate cortisol secretion in man. Owing to its immunosuppressive properties, an increase in cortisol levels during interleukin-2 cancer immunotherapy could potentially counteract induced activation of the antitumor immune response. Few data are available about cortisol secretion secondary to prolonged interleukin-2 administration. To investigate the problem, we evaluated cortisol circadian rhythms in 7 consecutive metastatic small cell lung cancer patients who received interleukin-2 subcutaneously for 4 weeks (daily dose: 6 x 10(6) x IU/m2). Venous blood samples were drawn at 8.00 a.m., 4.00 p.m. and 12.00 p.m., before interleukin-2, and after each week until the end of the cycle. Beta-endorphin levels were also measured on the same samples. Four patients were evaluated during a second interleukin-2 cycle. Mean cortisol levels increased during interleukin-2 therapy, but were significantly higher than those seen in basal conditions after the first week of treatment. Moreover, cortisol peaks observed during the second cycle of therapy were not significantly different from those seen during the first cycle. Mean beta-endorphin levels increased in response to interleukin-2 administration, but the increase did not reach statistical significance. The early cortisol rise progressively decreased as treatment continued. This suggests that the interleukin-2-induced cortisol rise has no relevant clinical importance in antagonizing the activation of an effective antitumor immune response during cancer immunotherapy with interleukin-2.