Incisor and mandibular movement during retrusion

Human mastication, respiration, speech, swallowing and suckling are directed by the jaw muscle activites, the temporo-mandibular joints, the ligaments and by the occlusal dental contacts. Mastication is usually assessed by border movements of the mandibular incisors. While the border movements of opening, protrusion and lateratrusion are often used to determine the mandibular functions, the movement of retrusion is rarely considered in the study of the human oro-facial functions. Our purpose was to evaluate the mandibular movement of retrusion in a population that did not present any symptoms nor clinical signs of temporo-mandibular disorders. The study was performed on 117 males and 121 females (age range: 17.7-65.2 years; mean age: 31.1 years) using electrognathographic registrations (Sirognatograph(*), Siemens, Benshein, Germany). Every patient was instructed and trained before recording. The measurements were calculated on the sagittal plane registrations. The results showed that the mandibular movement of retrusion was present in 233 out of the 238 studied subjects (97.9%) whatever was the dental class, the age or the sex. The width range was between 0.3 and 5.4 mm and the mean value was 1.75+/-0.91 mm. The inferential analysis performed by a 3-way ANOVA model demonstrated no significant difference in retrusion value by dental class, gender or age. The most frequent numerical value was 1.5 mm, observed in 16 subjects (6.7% of the studied population). These results suggest that, in order to respect the physiological characteristics, more attention is needed in performing dental treatments.

Effect on survival of treatment associated deep vein thrombosis in newly diagnosed multiple myeloma patients

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Background: Cancer patients experiencing thromboembolic disease have a poor prognosis. We report the effect on survival of treatment-associated DVT in myeloma patients. Methods: 668 newly diagnosed patients with progressive or symptomatic MM were enrolled in our Total Therapy 2 study, which included induction phase with VAD, DCEP, CAD and DCEP followed by high dose chemotherapy and tandem transplants. Patients were randomly assigned to receive Thalidomide or not during the whole treatment. Both arms otherwise received identical chemotherapy. Patients were followed and when clinically indicated underwent radiological studies to confirm a suspected DVT. If present, they were treated with low-molecular weight heparin followed by warfarin. Results: With a median follow up of 47 months a total of 158 patients experienced DVT; the median age was 57 years, 59% were male, 24% were IgA, 197 patients (30%) had abnormal cytogenetics (CA) including 100 patients with deletion of chromosome 13. The baseline characteristics were balanced between patients with and without DVT, with the exception of female gender, which was more prominent in the non DVT group (32% vs 46%, p = .018) on thalidomide, whereas CRP ≥ 8 mg/dl (57% vs 33%, p = .001), and IL6 > 9 pg/ml (47% vs 14%, p < .001) were more frequently observed in the DVT group on no thalidomide. Within each arm of the trial no significant differences in prognostic factors for survival (chromosomal abnormalities, low albumin level, β2-microglobulin, CRP) were seen. DVT status did not affect EFS (p = .3) or OS (p = .3) for the entire group, but a statistically longer EFS (p = .03) was observed in patients who developed a thromboembolic episode in the non thalidomide arm. No effect on survival (EFS p = .3; OS p = .95) was seen in the thalidomide arm. Conclusions: Development of DVT in newly diagnosed myeloma patients treated with chemotherapy ± thalidomide, does not affect overall survival. Patients not exposed to thalidomide who developed thrombosis during chemotherapy had significantly longer EFS. Our observation supports a survival benefit associated with anticoagulation therapy in cancer patients.

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Reduction of crying episodes owing to infantile colic: a randomized controlled study on the efficacy of a new infant formula

OBJECTIVES

The aim of this study was to evaluate the efficacy on crying episodes owing to infantile colic of a new infant formula containing partially hydrolysed whey proteins, prebiotic oligosaccharides (OS), with a high beta-palmitic acid content.

DESIGN

Prospective randomized controlled study.

SETTING

Italy.

SUBJECTS

Two hundred and sixty-seven formula-fed infants, aged less than 4 months, with infantile colic, were randomized to receive either the new infant formula (study treatment (ST)) or a standard formula and simethicone (6 mg/kg twice a day) (control treatment (CT)). A questionnaire was given to parents to evaluate for 14 days the daily number of colic episodes and crying time.

RESULTS

Out of the 199 infants who completed the study, 96 were treated with the new formula and 103 were not treated. Infants receiving the new formula had a significant decrease in colic episodes after 1 week (2.47+/-1.94 at day 7 vs 5.99+/-1.84 at the study entry) compared to infants receiving the CT (3.72+/-1.98 at day 7 vs 5.41+/-1.88 at the study entry) (P < 0.0001). Also at day 14, the crying episodes were significantly different between the two groups of infants (1.76+/-1.60 in ST vs 3.32+/-2.06 in CT) (P < 0.0001).

CONCLUSIONS

The use of a partially hydrolysed formula supplemented with fructo- and galacto-OS induces a reduction of crying episodes in infants with colic after 7 and 14 days when compared with a standard formula and simethicone.

Evaluation of the locus of control in patients with type 2 diabetes after long-term management by group care

AIM

To investigate the locus of control in patients with type 2 diabetes followed by systemic group education (Group Care) and traditional one-to-one care.

METHODS

In a post-hoc analysis, two questionnaires were administered to 56 patients who had been followed for 5-7 years by Group Care and 51 controls followed by individual care, similar by age, sex, diabetes duration, glycaemia, insulinaemia, weight and other clinical variables. Patients on Group Care had lower HbA1c (7.40 +/- 1.21%) than controls (7.99 +/- 1.48%), P = 0.027. The Peyrot and Rubin questionnaire, specific for diabetes, and the Wallston and Wallston questionnaire, more generic for chronic diseases, were administered. Both questionnaires explore 3 areas: internal control of disease, and the role of chance or powerful other people, including health operators, in changing the disease.

RESULTS

Both questionnaires showed lower scores for chance in patients followed by Group Care (P < 0.001), while scores for powerful others did not differ from those of patients followed by traditional care. The Peyrot and Rubin tool showed increased Internal Control (P < 0.001) in the patients followed by Group Care. Multivariate analysis showed that the HOMA index of insulin resistance was inversely related to Internal Control (B = -0.144, P = 0.005) independently of BMI and HbA1c.

CONCLUSION

Fatalistic attitudes were lower and internal control higher in patients with type 2 diabetes followed by Group Care. These changes may be related to insulin resistance, above and beyond the effects of body weight and metabolic control.

Incidence and prevalence rate estimation of GH treatment exposure in Piedmont pediatric population in the years 2002-2004: Data from the GH Registry

OBJECTIVE

The aim of this study is to estimate the annual incidence and prevalence rate of the GH treatment exposure in patients under the age of 18 treated for hypopituitarism or isolated GH deficiency (GHD) in Piedmont, during the period January 1, 2002 to December 31, 2004.

METHODS

The selection criteria for recombinant human GH (rhGH) treatment in childhood were approved by the Ministry of Health in Italy in the yr 1998. The present analysis is based on data from the Registry of subjects receiving GH therapy (GH Registry) made up of the 918 pediatric patients (age <18 yr) with a diagnosis of GHD (excluding Prader-Willi and Turner syndromes and other conditions), diagnosed in the period January 1, 2002 - December 31, 2004. The case series has been described as regards the number of cases per year of diagnosis; the prevalence and incidence rates, calculated per 10,000 (per ten thousand) inhabitants, are given for each year of the study period.

RESULTS

The prevalence rate increases slightly from 8.62 per thousand in 2002 to 9.44 per thousand in 2004 and the incidence rates estimated were 2.49 per ten thousand, 1.86 per ten thousand and 1.97 per ten thousand in the yr 2002, 2003 and 2004, respectively.

CONCLUSION

The Piedmont GH Registry represents the first database available in Italy and could set an example for the other Italian regions as well.

Anti-HER-2 DNA vaccine protects Syrian hamsters against squamous cell carcinomas

This paper illustrates the efficacy of DNA vaccination through electroporation in the prevention of oral transplantable carcinoma in Syrian hamsters. At 21 and 7 days before tumour challenge, 19 hamsters were vaccinated with plasmids coding for the extracellular and transmembrane domains of rat HER-2 receptor (EC-TM plasmids), whereas 19 control hamsters were injected intramuscularly with the empty plasmid. Immediately following plasmid injection, hamsters of both groups received two square-wave 25 ms, 375 V cm(-1) electric pulses via two electrodes placed on the skin of the injection area. At day 0, all hamsters were challenged in the submucosa of the right cheek pouch with HER-2-positive HCPC I cells established in vitro from an 7,12-dimethylbenz[a]anthracene-induced oral carcinoma. This challenge gave rise to HER-2-positive buccal neoplastic lesions in 14 controls (73.37%), compared with only seven (36.8%, P<0.0027) vaccinated hamsters. In addition, the vaccinated hamsters displayed both a stronger proliferative and cytotoxic response than the controls and a significant anti-HER-2 antibody response. Most of the hamsters that rejected the challenge displayed the highest antibody titres. These findings suggest that DNA vaccination may have a future in the prevention of HER-2-positive human oral cancer.

A 3-year prospective randomized controlled clinical trial of group care in type 1 diabetes

BACKGROUND AND AIMS

We showed that continuing education can be embedded into routine diabetes care by seeing patients in small groups rather than individually. Group care was cost-effective in improving quality of life, knowledge of diabetes, health behaviours and clinical outcomes in people with type 2 diabetes. The aim of this study was to verify if group care can also be applied to type 1 diabetes.

METHODS AND RESULTS

Randomized, controlled clinical trial comparing 31 patients managed by group care with 31 managed by traditional one-to-one care. A syllabus was built and later remodulated with the patients in a series of focus-group meetings. The primary end-point was changes in quality of life. Secondary end-points were: knowledge of diabetes, health behaviours, HbA1c and circulating lipids. Differential costs to the Italian National Health System and to the patients were also calculated. After 3 years, quality of life improved among patients on group care, along with knowledge and health behaviours (p<0.001, all). Knowledge added its effects to those of group care by independently influencing behaviours (p=0.004) while quality of life changed independently of either (p<0.001). Among controls, quality of life worsened (p<0.001) whereas knowledge and behaviours remained unchanged. HDL cholesterol increased among patients on group care (p=0.027) and total cholesterol decreased in the controls (p<0.05). HbA1c decreased, though not significantly, in both. Direct costs for group and one-to-one care were Euros 933.19 and Euros 697.10 per patient, respectively, giving a cost-effectiveness ratio of Euros 19.42 spent per point gained in the quality of life scale.

CONCLUSIONS

Group care is applicable and also cost-effective in type 1 diabetes. It improves quality of life, knowledge and behaviours. Future programme adjustments should strive to impact more on metabolic control.

A comparison of the alcohol-attributable mortality in four European countries

BACKGROUND

Deaths due to alcohol consumption are an important component of all-cause mortality, particularly premature mortality. However, there are considerable regional variations, the reasons for which are unclear.

METHODS

Estimates were made as reliably as possibly using vital statistics and best estimates of risk of the alcohol-attributable mortality, by age, sex and cause for four European countries (England and Wales, Germany, Denmark and Italy). Twenty-seven alcohol-related conditions were considered including the possible cardio-protective effects of alcohol.

RESULTS

It was estimated that there are approximately 2% fewer deaths annually in England and Wales than would be expected in a non-drinking population and 0.3% fewer deaths among East German females. In West Germany, Denmark, Italy and among East German males there are more deaths caused by alcohol than are prevented (between 0.7 and 2.6% of all deaths). The highest age-specific proportion of alcohol-attributable deaths is found in East Germany where around 30% of deaths among males aged 25-44 years are due to drinking. Among young men in all four countries the largest contributor to alcohol-related deaths is road traffic accidents involving alcohol.

CONCLUSIONS

Possible explanations for the variation in alcohol-attributable deaths between countries include different underlying heart disease rates, different patterns of alcohol consumption and beverage preferences, and different use of mortality classification. Differences in the reported alcohol consumption levels explain little of the variation in alcohol-attributable deaths. Estimating alcohol-attributable mortality by age and sex across countries may be a useful indicator for developing alcohol strategies and exploring ways of preventing premature mortality.

Multiple myeloma: comparison of two dose-intensive melphalan regimens (100 vs 200 mg/m2)

Several trials have shown the superior impact of high-dose melphalan (usually 200 mg/m(2), MEL200) vs standard therapy in myeloma patients. Intermediate-dose melphalan (100 mg/m(2), MEL100) is also superior to the standard dose, but has not been clinically compared with MEL200. A total of 90 patients at diagnosis were treated with two MEL100 courses. Their clinical outcome was compared with that of a control group of 90 pair mates matched for serum beta2-microglobulin levels and Durie and Salmon clinical stage. These patients were treated at diagnosis with two MEL200 courses. Patient characteristics were similar in both groups except that the median age of the MEL100 group was significantly higher (P<0.0001). Complete remission was 35% after MEL100 and 48% after MEL200 (P=0.08). Median event-free survival (EFS) was 32 months in the MEL100 group and 42 months in the MEL200 group (P<0.005), but overall survival (OS) was not different. Transplant-related mortality was not significantly different. Haematological and extra-haematological toxicity was significantly reduced after MEL100. Despite the significant age difference, tandem MEL100 was less toxic than tandem MEL200, and MEL100 was inferior to MEL200 in terms of EFS but not in terms of OS. The intensified nonmyeloablative MEL100 regimen is an effective first-line treatment.

"Minor" feeding problems during the first months of life: effect of a partially hydrolysed milk formula containing fructo- and galacto-oligosaccharides

BACKGROUND

Colic, regurgitation and constipation are common feeding problems in formula-fed infants that might benefit from dietary treatment. A formula containing fructo- and galacto-oligosaccharides, partially hydrolysed proteins, low levels of lactose and palmitic acid in the beta position and higher density has been tested to reduce the occurrence of these symptoms. The aim of this prospective study was to describe the effects of such a formula in infants with minor gastrointestinal disorders.

METHODS

An observational prospective trial involving practising Italian paediatricians was performed. Formula fed-infants up to 90 d of age with minor gastrointestinal problems such as infantile colics and/or regurgitation and/or constipation were enrolled in the study from January 2001 to May 2001. The study was completed within 14 d of treatment. On days 1, 7 and 14 the infants were visited by the paediatricians. Parents were given a structured diary to record daily episodes of colic, regurgitation and type and number of stools.

RESULTS

Of the 932 infants enrolled, 604 completed the study. Of the 214 infants with colic, 169 (79%) demonstrated a reduction in frequency of colic from 4.1 +/- 2.0 per day at the beginning of the study to 2.0 +/- 1.8 at the end of the study (I.C. 95%: 1.72-2.39; p < 0.005). A reduction in the number of episodes of colic of 1.8 per day at the beginning of the study (I.C. 95%: 1.49-2.11; p < 0.05) was recorded between day 1 and day 7, and of 0.26 (I.C. 95%: 0.15-0.37; p < 0.05) between day 7 and day 14. Of the 201 infants with regurgitation problems, 141 (70%) demonstrated a reduction of frequency of the symptoms from 4.2 +/- 2.0 per day at the beginningof the study to 2.1 +/- 2.2 at the end of the study (I.C. 95%: 1.75-2.35; p < 0.005). A reduction of 1.87 in the number of regurgitation episodes was reported between day 1 and day 7 (I.C. 95%: 1.57-2.16; p < 0.05) and of 0.18 (I.C. 95%: 0.06-0.31; p < 0.05) between day 7 and day 14. Of the 232 infants with constipation, 147 (63%) demonstrated an increase in the daily number of stools of 0.42 (I.C. 95%: 0.5-0.3; p < 0.005). An increase in stool frequency of 0.41 (I.C. 95%: 0.51-0.23; p < 0.05) was reported between day 1 and day 7, and of 0.04 (I.C. 95%: 0.22-0.14; p = ns) between day 7 and day 14. Parents' evaluation of the formula was 7.9 +/- 1.8 (score 0-10); 550 parents (91%) gave a positive judgement (score > 6). The evaluation by the paediatricians of the improvement in symptoms after the treatment was 8.2 +/- 1.5; 574 (95%) a positive effect (score > 6).

CONCLUSION

This study shows that the majority of infants followed by paediatricians for minor gastrointestinal symptoms improve within 2 wk of feeding with this new formula. Further double-blind, controlled studies are needed to confirm whether the amelioration of symptoms observed in this trial is in fact due to the new formula.

Perceptions of diabetic retinopathy and screening procedures among diabetic people

AIMS

To assess how diabetic patients perceive retinopathy, screening for sight-threatening lesions and their own role in preventing blindness.

METHODS

A questionnaire was administered to 258 consecutive patients after screening for retinopathy, according to the European Field Guide-Book procedure, in Turin (n = 130) and Wales (n = 128, W). All Welsh patients and 70 in Turin (T1) were on standard diabetes care at their clinic or general practitioner, whereas 60 in Turin (T2) were on permanent group education.

RESULTS

According to 65%, 84% and 100% of patients in W, T1 and T2, respectively, diabetes may damage the eyes. Retinopathy had been heard of by 48% (W), 67% (T1) and 100% (T2). In T2, 82% of patients could give a meaningful description of retinopathy but only 17% could use correctly the word 'retina'. In W and T1, 16% and 19% could describe retinopathy but none could describe the retina. In W and T1, 47% and 57% believed they could not help with eye care, whereas 78% in T2 replied that they should control diabetes and 20% that eyes should be checked regularly. Regarding reasons for screening, 100% of patients in T2 answered 'prevention and checks', against 61% in T1 and only 9% in W. In T1 and W, 33% and 37% did not know why they were being screened.

CONCLUSIONS

Patients' health perceptions and internal control mechanisms may be insufficiently developed for optimal participation in retinopathy screening. Diabetes care by long-term group education may address this problem.

Lifestyle intervention by group care prevents deterioration of Type II diabetes: a 4-year randomized controlled clinical trial

AIMS/HYPOTHESIS

Metabolic control worsens progressively in Type II (non-insulin-dependent) diabetes mellitus despite intensified pharmacological treatment and lifestyle intervention, when these are implemented on a one-to-one basis. We compared traditional individual diabetes care with a model in which routine follow-up is managed by interactive group visits while individual consultations are reserved for emerging medical problems and yearly checks for complications.

METHODS

A randomized controlled clinical trial of 56 patients with non-insulin-treated Type II diabetes managed by systemic group education and 56 control patients managed by individual consultations and education.

RESULTS

Observation times were 51.2+/-2.1 months for group care and 51.2+/-1.8 for control subjects. Glycated haemoglobin increased in the control group but not in the group of patients ( p<0.001), in whom BMI decreased ( p<0.001) and HDL-cholesterol increased ( p<0.001). Quality of life, knowledge of diabetes and health behaviours improved with group care ( p<0.001, all) and worsened among the control patients ( p=0.004 to p<0.001). Dosage of hypoglycaemic agents decreased ( p<0.001) and retinopathy progressed less ( p<0.009) among the group care patients than the control subjects. Diastolic blood pressure ( p<0.001) and relative cardiovascular risk ( p<0.05) decreased from baseline in group patients and control patients alike. Over the study period, group care required 196 min and 756.54 US dollars per patient, compared with 150 min and 665.77 US dollars for the control patients, resulting in an additional 2.12 US dollars spent per point gained in the quality of life score.

CONCLUSION/INTERPRETATION

Group care by systemic education is feasible in an ordinary diabetes clinic and cost-effective in preventing the deterioration of metabolic control and quality of life in Type II diabetes without increasing pharmacological treatment.

Combined allogeneic tumor cell vaccination and systemic interleukin 12 prevents mammary carcinogenesis in HER-2/neu transgenic mice

Transgenic Balb/c mice expressing the transforming rat HER-2/neu oncogene develop early and multifocal mammary carcinomas. Within the first 5 months of life the tissue-specific expression of HER-2/neu causes a progression in all their 10 mammary glands from atypical hyperplasia to invasive carcinoma. It was previously observed that chronic administration of interleukin (IL)-12 increased tumor latency, but every mouse eventually succumbed to multiple carcinomas. A significant improvement in tumor prevention was sought by administering allogeneic mammary carcinoma cells expressing HER-2/neu combined with systemic IL-12. This treatment reduced tumor incidence by 90% and more than doubled mouse lifetime. For the maximum prevention p185(neu) antigen must be expressed by allogeneic cells. IL-12 treatment strongly increased the cell vaccine efficacy. The mammary glands of mice receiving the combined treatment displayed a markedly reduced epithelial cell proliferation, angiogenesis, and HER-2/neu expression, while the few hyperplastic foci were heavily infiltrated by granulocytes, macrophages, and CD8(+) lymphocytes. Specific anti-HER-2/neu antibodies were produced and a nonpolarized activation of CD4(+) and CD8(+) cells secreting IL-4 and interferon (IFN)-gamma were evident. A central role for IFN-gamma in the preventive effect was proven by the lack of efficacy of vaccination in IFN-gamma gene knockout HER-2/neu transgenic Balb/c mice. A possible requirement for IFN-gamma is related to its effect on antibody production, in particular on IgG2a and IgG2b subclasses, that were not induced in IFN-gamma knockout HER-2/neu mice. In conclusion, our data show that an allogeneic HER-2/neu-expressing cell vaccine combined with IL-12 systemic treatment can prevent the onset of genetically determined tumors.

Public health training in Europe. Development of European masters degrees in public health

BACKGROUND

Changing political and economic relations in Europe mean that there are new challenges for public health and public health training. There have been several attempts to develop training at the master's level in public health which is focused on meeting the new needs. These have failed due to being too inflexible to allow participation by schools of public health.

METHODS

A project funded by the European Union involving public health trainers has developed a new approach which allows participating schools to retain their national differences and work within local rules and traditions, but which aims to introduce the European dimension into public health training. This paper reports the conclusions of this project.

CONCLUSIONS

A network of schools wishing to develop European Master's degrees is being established and other schools offering good quality programmes will be able to join.

Interleukin 12-activated lymphocytes influence tumor genetic programs

T-lymphocytes (LYs) from normal and IFN-gamma knockout mice were activated by anti-CD3 and anti-CD28 antibodies and cultured in inserts in the presence of interleukin (IL)-12 (IL-12-activated LYs) or not (activated LYs). Their ability to modulate the genetic programs of two tumor lines growing at the bottom of transwells was evaluated. cDNA gene expression array, reverse transcription-PCR, and protein expression showed that LPS, transcription termination factor 1, transforming growth factor, and fibroblast growth factor genes were up-modulated by factors other than IFN-gamma released by activated LYS: The high levels of IFN-gamma released by normal IL-12-activated LYs up-modulated the expression of STAT1, IRF-1, LMP2, LMP7, monokine induced by IFN-gamma, monocyte chemoattractant protein 1, and angiopoietin 2 genes but down-modulated the expression of vascular endothelial growth factor. PA28, IFN-inducible protein 10, inducible NO synthetase, and macrophage-inhibitory protein 2 genes were up-modulated by factors released only by IL-12-activated LYs apart from IFN-gamma. The opposite modulations of vascular endothelial growth factor expression and of angiopoietin 2, monokine induced by IFN-gamma, IFN-inducible protein 10, and inducible NO synthetase by IL-12-activated LYs fit in well with the inhibition of angiogenesis that characterizes the antitumor activity of IL-12. T-LYs thus modify a tumor's behavior so that it becomes a party to its own inhibition.

A light, nontoxic interleukin 12 protocol inhibits HER-2/neu mammary carcinogenesis in BALB/c transgenic mice with established hyperplasia

With a slight asynchronous but consistent progression, all of the mammary glands of female BALB/c mice transgenic for the transforming rat HER-2/neu oncogene progress to atypical hyperplasia and to invasive carcinoma. Previous studies have shown that chronic administration of interleukin (IL) 12 started at the 2nd week of age hampers this progression because of its ability to inhibit tumor angiogenesis and activate a nonspecific immune response. Here we show that a similar inhibition is achieved when 7-week-old mice with fully blown atypical hyperplasia receive a weekly injection of 100 ng IL-12 for 16 times. This lower-dose and later IL-12 administration induces high and sustained levels of serum IFN-gamma equivalent to those elicited by more frequent administrations. A lower-dose and less toxic treatment may thus be envisaged as a possible option in the management of preneoplastic mammary lesions.

IL-12 inhibition of endothelial cell functions and angiogenesis depends on lymphocyte-endothelial cell cross-talk

In vivo IL-12-dependent tumor inhibition rests on the ability of IL-12 to activate a CD8-mediated cytotoxicity, inhibit angiogenesis, and cause vascular injury. Although in vivo studies have shown that such inhibition stems from complex interactions of immune cells and the production of IFN-gamma and other downstream angiostatic chemokines, the mechanisms involved are still poorly defined. Here we show that IL-12 activates an anti-angiogenic program in Con A-activated mouse spleen cells (activated spc) or human PBMC (activated PBMC). The soluble factors they release in its presence arrest the cycle of endothelial cells (EC), inhibit in vitro angiogenesis, negatively modulate the production of matrix metalloproteinase-9, and the ability of EC to adhere to vitronectin and up-regulate ICAM-1 and VCAM-1 expression. These effects do not require direct cell-cell contact, yet result from continuous interaction between activated lymphoid cells and EC. We used neutralizing Abs to show that the IFN-inducible protein-10 and monokine-induced by IFN-gamma chemokines are pivotal in inducing these effects. Experiments with nu/nu mice, nonobese diabetic-SCID mice, or activated spc enriched in specific cell subpopulations demonstrated that CD4(+), CD8(+), and NK cells are all needed to mediate the full anti-angiogenetic effect of IL-12.

Ability of systemic interleukin-12 to hamper progressive stages of mammary carcinogenesis in HER2/neu transgenic mice

Previous studies in mice have shown that chronic administration of recombinant interleukin-12 (IL-12) hampers the progression of both chemical- and oncogene-dependent carcinogenesis. This suggests that a new preventive strategy may be envisaged for individuals with a genetic risk of cancer or carrying preneoplastic lesions. Starting at progressive stages of mammary carcinogenesis, female BALB/c and FVB mice carrying the activated rat HER2/neu oncogene (BALB-neuT) or the proto-oncogene (FVB-neuN) under the mouse mammary tumor virus promoter received multiple 5-day courses of different doses of IL-12. The times of tumor appearance, multiplicity, and histopathological features of the neoplastic lesions were evaluated. In both BALB-neuT and FVB-neuN mice, 5-day i.p. courses of 50/100 ng of IL-12/day inhibited mammary carcinogenesis when they coincided with the progression of early preneoplastic lesions. Inhibition appears to depend primarily on the ability of IL-12 to interfere with early tumor angiogenesis. Later treatments are much less effective, and daily doses of 10 and 2 ng are useless. The efficacy of early IL-12 courses suggests that they could be used to prevent mammary tumors in individuals at risk, whereas their lower efficacy in later stages of carcinogenesis and the dose range required pose some constraints on their use in the management of overt preneoplastic lesions. Precise understanding of tumor progression means that effective treatments can be commenced relatively late in the life of individuals at risk and that no lifetime administration is required.

Interleukin-2 gene transfer into human transitional cell carcinoma of the urinary bladder

Transitional cell carcinoma of the bladder is one of the human cancers most responsive to immunotherapy, and local interleukin-2 (IL-2) production appears to be an important requirement for immunotherapy to be effective. In this study, we engineered two human bladder cancer cell lines (RT112 and EJ) to constitutively release human IL-2 by retroviral vector-mediated gene transfer. Following infection and selection, stable and consistent production of biologically active IL-2 was demonstrated at both the mRNA and the protein level. Morphology, in vitro growth rate and proliferation, as well as other cytokine gene mRNA or membrane adhesion receptor expression, were not altered in IL-2 transduced cells as compared to their parental or control vector-infected counterparts. Moreover, IL-2 engineered cells lost their tumorigenicity into nu/nu mice and the mechanism of rejection appeared to involve multiple host effector cell populations, among which a prominent role was played by neutrophils and radiosensitive cells. These findings may offer support to the development of an IL-2-based gene therapy approach to human bladder cancer.

Immune events associated with the cure of established tumors and spontaneous metastases by local and systemic interleukin 12

The antitumor activity of recombinant murine interleukin-12 (rIL-12) is documented by a large set of data from numerous mouse models. Because the cellular and molecular mechanisms by which rIL-12 impairs tumor growth are still not fully defined, we compared the effects of local and systemic rIL-12 administration in mice harboring an invasive 7-day-old moderately differentiated and spontaneously metastasizing mammary adenocarcinoma (TSA). Whereas the immune events elicited via the two routes of rIL-12 administration seem to be the same, systemic rIL-12 is markedly more effective; tumor destruction is dependent on a prompt antitumor response resulting from the cooperation of several subsets of reactive cells. The reactions that seem to play a key role are: (a) indirect inhibition of angiogenesis by secondary cytokines (mainly IFN-gamma) and third-level chemokines (inducible protein 10 and monokine induced by IFN-gamma); (b) systemic activation of leukocyte subsets capable of producing proinflammatory cytokines, CTLs, and antitumor antibodies; and (c) destruction of tumor vessels by polymorphonuclear cells. The markedly higher efficacy of systemic rIL-12 seems to rest on its ability to recruit these systemic reactions more quickly and efficiently than local rIL-12.

Interleukin 12-mediated prevention of spontaneous mammary adenocarcinomas in two lines of Her-2/neu transgenic mice

The ability of interleukin (IL)-12 to prevent tumors when administered to individuals with a genetic risk of cancer was studied in two lines of transgenic mice expressing rat HER-2/neu oncogene in the mammary gland. Female BALB/c (H-2(d)) mice carrying the activated HER-2/ neu oncogene show no morphological abnormalities of the mammary gland until 3 wk of age. They then progress through atypical hyperplasia to in situ lobular carcinoma and at 33 wk of age all 10 mammary glands display invasive carcinomas. Adult FVB mice (H-2(q)) carrying the HER-2/neu protooncogene develop mammary carcinomas with a longer latency (38-49 wk) and a lower multiplicity (mean of 2.6 tumors/mice). Treatment with IL-12 (5 daily intraperitoneal injections, 1 wk on, 3 wk off; the first course with 50 ng IL-12/day, the second with 100 ng IL-12/day) begun at 2 wk of age in BALB/c mice and at 21 wk of age in FVB mice markedly delayed tumor onset and reduced tumor multiplicity. Analogous results were obtained in immunocompetent and permanently CD8(+) T lymphocyte-depleted mice. In both transgenic lines, tumor inhibition was associated with mammary infiltration of reactive cells, production of cytokines and inducible nitric oxide synthase, and reduction in microvessel number, in combination with a high degree of hemorrhagic necrosis.

The immune response elicited by mammary adenocarcinoma cells transduced with interferon-gamma and cytosine deaminase genes cures lung metastases by parental cells

The parental cells of the TSA murine mammary adenocarcinoma (TSA-pc) were transfected with both the interferon-gamma (IFN-y) gene and the cytosine deaminase (CD) suicide gene to obtain a therapeutic vaccine active against TSA-pc lung metastases. Even in the absence of treatment with the prodrug 5-fluorocytosine (5-FC), the local growth of double transfectants (CD-y clones) was inhibited by a marked recruitment of granulocytes and macrophages. In mice harboring TSA-pc micrometastases, therapeutic vaccination with either IFN-gamma or CD single transfectants reduced the number of lung nodules, whereas CD-gamma double transfectants abrogated metastasis growth in up to 80% of mice. Treatment of mice with 5-FC did not alter the curative efficacy of CD-gamma double-transfectant cells. By contrast, in mice vaccinated with CD single-transfectant cells, 5-FC treatment caused a significant loss of their curative activity. Host T cells played an active role in the cure of lung metastases, because vaccination of nude mice with CD-gamma cells was uneffective.

Antitumor efficacy of adenocarcinoma cells engineered to produce interleukin 12 (IL-12) or other cytokines compared with exogenous IL-12

BACKGROUND

Numerous animal model studies have examined the ability of genetically engineered tumor cells to release cytokines and to elicit an immune memory against the parental tumor. Often only a single cytokine is studied, and few comparative studies have been conducted.

PURPOSE

We evaluated the antitumor efficacy of adenocarcinoma cells engineered to release interleukin (IL)-12 in a mouse model system. The efficacy of this cytokine was compared with that of other cytokines released by engineered adenocarcinoma cells and that of exogenous IL-12 administered both locally and intraperitoneally.

METHODS

BALB/cAnCr mice were inoculated with syngeneic parental mammary adenocarcinoma (TSA) cells in quantities sufficient to lead to tumors in all inoculated mice. TSA cells engineered to release IL-12 (TSA-IL12) were also injected into normal and selectively immunosuppressed BALB/cAnCr mice. Tumor incidence, growth, and rejection patterns were evaluated by the measurement of neoplastic masses and by the study of the histologic and ultrastructural features of the tumor site. The effects of local or intraperitoneal administration of recombinant IL-12 (rIL-12) on tumor-bearing animals were also studied.

RESULTS

Most mice rejected TSA-IL12 cells through a CD8-positive, T-lymphocyte-dependent reaction associated with macrophage infiltration, vessel damage, and necrosis. The systemic immunity of mice that had rejected TSA-IL12 cells to a subsequent challenge with parental TSA cells was less efficient than that elicited by TSA cells engineered to release IL-4 or IL-10 but equivalent to that elicited by TSA cells engineered to release IL-2, IL-7, and interferon alfa. Compared with TSA cells engineered to produce other cytokines, TSA-IL12 cells were the most efficient in curing mice with established TSA tumors; injection of 0.1 million proliferating cells contralaterally to the tumor growth area cured five of 15 mice bearing 1-day-old tumors; injection of the same dose of proliferating cells into the tumor growth area cured two of 20 tumor-bearing mice. However, two 5-day courses with a nontoxic dose (0.1 microgram) of rIL-12 given intraperitoneally cured a similar proportion of these animals (six of 20). Only two of 20 mice with 7-day-old TSA tumors were cured by vaccination with proliferating TSA-IL12 cells, whereas 24 of 30 mice with such tumors were cured by intraperitoneal administration of rIL-12.

CONCLUSIONS

TSA cells engineered to release IL-12 are rejected by most mice; the ensuing immune memory for TSA parental cells, however, was less efficient than that elicited by proliferating TSA cells engineered to release other cytokines (e.g., IL-4, IL-10, and possibly interferon gamma). The immune reaction elicited by TSA-IL12 cells was the most efficient in curing mice with established TSA tumors; notably though, the same or a better cure rate was obtained with rIL-12 given intraperitoneally.

Constitutive expression of lymphoma-associated NFKB-2/Lyt-10 proteins is tumorigenic in murine fibroblasts

The NFKB-2 (Lyt-10) gene codes for an NF-kappaB-related transcription factor containing rel-polyG-ankyrin domains. Rearrangements of the NFKB-2 locus leading to the production of 3' truncated NFKB-2 proteins are recurrently found in lymphoid neoplasms, particularly cutaneous lymphomas. Such mutant NFKB-2 proteins have lost the ability to repress transcription that is typical of NFKB-2 subunit p52, and function as constitutive transcriptional activators. To verify whether the expression of abnormal NFKB-2 proteins can lead to malignant transformations in mammalian cells, we transfected human lymphoblastoid cell lines and murine fibroblasts (Balb/3T3) with expression vectors carrying the cDNAs coding for normal NFKB-2p52, Lyt-10C alpha or LB40 proteins, which are representative of the abnormal types found in lymphoma cases. The expression of both normal and mutant NFKB-2 proteins has a lethal effect on lymphoblastoid cells and a cytotoxic effect was also observed in murine fibroblasts. The fibroblast cell lines expressing Lyt-10C alpha or LB40, but not those expressing normal NFKB-2p52, were capable of forming colonies in soft agar. The analysis of individual clones revealed that cloning efficiency correlated with the expression levels of the abnormal proteins. Injection of the Lyt-10C alpha-transfected Balb cells in SCID mice led to tumor formation in all of the animals, whereas no tumors were observed in the mice injected with control or NFKB-2p52-transfected cells, thus indicating that abnormal NFKB-2 protein expression is tumorigenic in vivo. Our results show that mutant NFKB-2 proteins can lead to the transformed phenotype, and support the hypothesis that alterations in NFKB-2 genes may play a role in lymphomagenesis.

Therapy of murine mammary carcinoma metastasis with interferon gamma and MHC gene-transduced tumour cells

Gene-transfected tumour cells were used to cure mice bearing lung metastases by the parental, non-transduced mammary adenocarcinoma (TSA-pc). Repeated subcutaneous (s.c.) administrations of mitomycin C (MitC)-treated interferon gamma (IFN-gamma) transfectants induced a 90% inhibition in the number of lung metastases. Therapeutic effect required an intact T-cell response, as shown by the lack of efficacy in nude mice. Autocrine stimulation by IFN-gamma induces specific modifications in the phenotype of transfectants that acquire a high metastatic ability and show a high expression of IFN-responsive genes; these two features were exploited to design two experimental protocols to obtain an improvement of the therapeutic effect. The increased metastatic ability of IFN-gamma transfectants was used to deliver IFN-gamma selectively to the lungs of mice bearing TSA-pc pulmonary metastases. A significant therapeutic effect was obtained when TSA-pc experimental metastases were treated by repeated intravenous (i.v.) injections of MitC IFN-gamma transfectants. Since i.v. administrations of IFN-gamma transfectants did not induce immune memory, the therapeutical effect appeared to depend on the inflammatory-like response activated by local IFN release. To exploit the autocrine stimulation of IFN-sensitive genes an IFN-gamma transfectant clone was subjected to a second transfection with an allogeneic class I MHC gene (H-2K(b) or H-2D(h)). IFN-gamma plus MHC double transfectants maintained IFN-gamma release, showed a very high expression of the MHC gene products, stimulated both macrophages and T cells, and were less tumorigenic in immunocompetent mice than the parent IFN-gamma clone. Therapeutic efficacy of double transfectant IFN-gamma plus H-2D(b) cells against TSA-pc was superior to single transfectants, showing that the reaction elicited by genetically engineered cells can be selectively tuned to increase therapeutic efficacy.

Heterogeneous effects of B7-1 and B7-2 in the induction of both protective and therapeutic anti-tumor immunity against different mouse tumors

Experimental mouse tumors are classified as intrinsically immunogenic when, after a single injection into syngeneic mice as nonreplicating cell vaccines, they elicit a protective immune response against a subsequent lethal challenge. Tumors that do not retain this residual immunogenicity are defined as poorly immunogenic or nonimmunogenic. The expression of the B7-1 co-stimulatory molecule on immunogenic tumors can further increase their capacity to induce a T cell-dependent anti-tumor immunity, whereas it has limited effects on nonimmunogenic tumors. Recently, B7-2, a second molecule with an apparently similar co-stimulatory activity, has been cloned. In this report, we compare the efficiency of nonreplicating cells from one immunogenic and two nonimmunogenic mouse tumors transfected with B7-1 or B7-2 in the induction of protective and curative anti-tumor immunity. Immunogenic lymphoma cells expressing B7-1 or B7-2 are equally effective in both protecting against a subsequent challenge and curing established tumors. By contrast, nonimmunogenic adenocarcinoma and melanoma cells expressing B7-2 provide superior protective immunity, and only B7-2+ adenocarcinoma cells induce an efficient curative immunity. CD8+ and polymorphonuclear cells, but not CD4+ T cells, are critically involved in the rejection of the adenocarcinoma elicited by both B7-1+ and B7-2+ vaccines. These data indicate that B7-1 and B7-2 are not redundant co-stimulatory molecules and that, in these experimental models, B7-2 is superior to B7-1 in the induction of an efficient immunity when the immunogenicity of a tumor is a limiting factor.

An international comparison of knowledge levels of medical students: the Maastricht Progress Test

The increasing international mobility of medical students has inspired the search for an international assessment format. As one step along this line, kinetics of knowledge acquisition and final cognitive levels of students were compared among one Dutch, one German and four Italian medical faculties. For this comparison, the Maastricht Progress Test (MPT) was used. For four out of the six participating faculties, it was possible to compare the level of knowledge of sixth-year students. These data showed no significant differences on the test as a whole. On the other hand, as judged from cross-sectional data on students from all study years, the kinetics of knowledge acquisition showed different trends. In one school applying problem-based learning, acquisition of knowledge by students occurred almost linearly. In another school, over the first 2 years, acquisition of knowledge occurred only in the basic sciences but not in clinical or public health/behavioural sciences. In two other schools over that same period, students seemed to gain no knowledge at all. In some faculties, a marked boost in knowledge was noted with third- or fourth-year students. These findings may be explained by peculiarities of the respective curricula, selection of students during their studies, and national or local assessment procedures. It is preliminarily concluded that the different educational approaches and assessment systems in medical education in Europe seem to have only limited influence on the final level of knowledge of the graduates. On the other hand, these differences may influence the kinetics of knowledge acquisition, especially in distinct domains like basic or clinical sciences. Therefore, the MPT may not be suitabe to solve the problem of assessment of individual international exchange students, but it may be helpful in identifying corresponding cognitive levels on, for example, basic sciences for students in different curricula.

Adriamycin-induced proteinuria in nude mice: an immune-system-mediated toxic effect

BACKGROUND

The renal minimal lesion disease induced in rats by adriamycin (ADR) is generally thought to be consequent to a direct cytotoxic effect of this drug on glomerular epithelial cells. Only recently an altered synthesis of mediators, including reactive oxygen species and monocyte-macrophage cytokines, has been hypothesized.

METHODS

A mouse strain (nude) bearing a congenital thymic aplasia is a suitable experimental animal to evaluate the role of immune reactions in the development of the ADR nephropathy, provided mouse susceptibility to its toxic effect. Therefore, experimental mice were divided into three groups (G) each receiving adriamycin 7.5 mg/kg b.w.: GA (15 heterozygous nu/O mice with normal immune system); GB (15 homozygous nu/nu athymic mice); GC (15 homozygous nu/nu mice which were also splenectomized, irradiated, and treated with anti-asialo Gm1 antibody to abolish NK and decrease macrophage activity). All animals were maintained under pathogen-free conditions. Urinary proteins, albumin and TNF-alpha excretion were measured.

RESULTS

After 14 days the proteinuria was 43.8+/-1.7 microg/min in GA, 30.2+/-2.9 microg/min in GB (P<0.05) and 12.2+/-2.8 microg/min in GC (GA vs GC, P<0.0001; GB vs GC, P<0.05). Albuminuria gave a similar profile. TNG-alpha urinary excretion was significantly higher in GA (17.3+/-3.2 mU/min) than in GB (5+/-0.6 mU/min, P<0.001) and GC (3.2+/-0.9 mU/min, P<0.001). A significant correlation was found in GA between urinary TNF-alpha and protein losses (r2=0.63 P<0.0001). Kidney tissue homogenates failed to show in each experimental group any evidence of mRNA encoding for TNF-alpha, which was detectable in peripheral mononuclear cells from GA and GB, but undetectable in GC mice. Segmental effacements of glomerular epithelial cell foot process were observed by electron-microscopy in GA only, while they were minimal in GB and absent in GC. Iron colloidal staining for anionic sites on frozen sections always showed a normal pattern.

CONCLUSIONS

Nude mice bearing cellular immunity deficiency are protected from proteinuria following ADR toxicity. An impaired synthesis and release of lymphomonocyte mediators including TNF-alpha could be envisaged.

Interleukin 12 potentiates the curative effect of a vaccine based on interleukin 2-transduced tumor cells

The purpose of these studies was to determine whether systemic administration of recombinant interleukin 12 (rIL-12) is able to potentiate an initial, but insufficient T-cell antitumor response. Mice challenged with carcinoma cells engineered to release interleukin 2 (IL-2) and displaying such a response received single or multiple i.p. injections of rIL-12. This combination of systemic rIL-12 and local IL-2 increased the percentage of mice that rejected two different IL-2 gene-transduced tumors. In another set of experiments more closely resembling a clinical situation, IL-2 gene-transduced tumors were used as vaccines in an attempt to cure mice bearing wild-type parental tumors. The combination of these vaccines with systemic rIL-12 cured mice more effectively than rIL-12 and IL-2 gene-transduced tumor vaccines alone.

Evaluation of c-ras oncogene product (p21) in superficial bladder cancer

OBJECTIVES

The aim of our study is the evaluation of the prognostic importance of p21 protein in superficial bladder cancer.

METHODS

One hundred and fourteen patients with an initial diagnosis of monofocal bladder cancer (stage Ta-T1) following TUR were investigated. On the tissue removed by TUR, besides the usual pathological evaluation, an immuno-histochemical investigation was carried out in order to ascertain the presence of c-ras oncogene product (protein p21). The actuarial curves concerning the time free from the first recurrence were computed, comparing different subgroups in regard to protein p21 presence, grade and stage of the tumour.

RESULTS

The analysis of the results shows the importance of tumour stage as a predictor of recurrence, as well as that of the presence of c-ras products. This last factor increases the risk of recurrence almost 2-fold, in the same time lag, for c-ras-positive patients (p < 0.001). The prognostic significance of c-ras is independent of stage.

CONCLUSION

Our data underline the possibility of acquiring important information on the prognosis of superficial bladder cancer patients, pointing out the significance of c-ras oncogene product.

Role of neutrophils and lymphocytes in inhibition of a mouse mammary adenocarcinoma engineered to release IL-2, IL-4, IL-7, IL-10, IFN-alpha, IFN-gamma, and TNF-alpha

Impressive inhibition of tumor growth has been observed after transduction of cytokine genes into tumor cells. Secreted cytokines do not affect the proliferation of a tumor directly but activate a host immune reaction strong enough to overcome its oncogenic capacity. However, the reaction mechanisms activated are difficult to interpret; because these mechanisms have been derived from experiments with different tumors, comparisons are hindered. To compare the reactive mechanisms induced by each cytokine, BALB/c mice were challenged with the parental cells of the syngeneic spontaneous mammary adenocarcinoma TSA, or with TSA cells engineered to release IL2, IL4, IL7, IL10, IFN alpha, IFN gamma, and TNF alpha, and the tumor growth area was studied histologically, ultrastructurally, and immunohistochemically. These observations were integrated with data on the growth and rejection patterns of TSA cells in mice depleted of natural killer (NK) cells, granulocytes, CD4+, or CD8+ lymphocytes. The rejection of TSA-IL2 and TSA-TNF alpha cells was associated with the massive presence of neutrophils, that of TSA-IL4 and TSA-IL7 cells with neutrophils and very small areas of colliquative necrosis, and that of TSA-IFN alpha and TSA-IL10 cells with extensive areas of ischemic-coagulative necrosis and some neutrophils. TSA-IFN gamma cells displayed a delay in growth, but were not rejected. Their growth areas comprised necrotic zones of ischemic necrosis devoid of neutrophils. The selective depletion experiments demonstrated that rejection of engineered TSA cells depends on several leukocyte populations. The weight of each population varied with the secreted cytokine, although neutrophils and CD8+ lymphocytes constantly played the major role. Employment of the same tumor line engineered with the genes of different cytokines showed that each cytokine evokes a distinct reaction and that tumor inhibition results from a complex mechanism in which neutrophils and CD8+ lymphocytes and ischemic necrosis are of primary importance.

Molecular approaches to cancer immunotherapy

The use of cytokines and costimulatory molecule gene-engineered tumor cells to enhance tumor immunogenicity and elicit curative responses against established tumors and tumor recurrences has become an attractive prospect. The immunotherapy data obtained in many experimental tumor systems using these engineered cells are reviewed here to provide a realistic assessment of the potential and limits of this technique.

Local release of IL-10 by transfected mouse mammary adenocarcinoma cells does not suppress but enhances antitumor reaction and elicits a strong cytotoxic lymphocyte and antibody-dependent immune memory

The cDNA coding for mouse IL-10 (mIL-10) was transduced into the parental cells of a spontaneous adenocarcinoma of BALB/c mice (TSA-pc), and clones secreting small, medium, and large quantities of IL-10 were selected. In vivo, both low and high producer clones do not display an enhanced ability to grow in H-2 and non-H-2 incompatible mice. Instead, the intensity of their rejection increases in function of the amount of mIL-10 released. After an initial growth period in syngeneic mice, high producer clones undergo complete rejection due to the combined action of CD8+ lymphocytes, NK cells, and neutrophils. After this rejection, mice are immune to a subsequent challenge with TSA-pc. This memory rests on a strong lytic activity of CD8+ CTL and granulocytes. Following the rejection, mice also develop anti-TSA Ab that guide the granulocytes in TSA-pc memory reaction. A direct comparison shows that although TSA clones engineered to release IL-2 activate CTL and no anti-TSA Ab, those engineered to release IL-4 activate a strong Ab response but not CTL. The kind of cytokine released by the tumors appears to determine the type of response. However, IL-10 high producer cells do not deviate the immune memory, neither toward a Th1 nor a Th2. Both the CTL activity and the Ab responses induced by IL-10 high producer cells are the strongest so far observed in the TSA system.

Local release of IL-10 by transfected mouse mammary adenocarcinoma cells does not suppress but enhances antitumor reaction and elicits a strong cytotoxic lymphocyte and antibody-dependent immune memory

The cDNA coding for mouse IL-10 (mIL-10) was transduced into the parental cells of a spontaneous adenocarcinoma of BALB/c mice (TSA-pc), and clones secreting small, medium, and large quantities of IL-10 were selected. In vivo, both low and high producer clones do not display an enhanced ability to grow in H-2 and non-H-2 incompatible mice. Instead, the intensity of their rejection increases in function of the amount of mIL-10 released. After an initial growth period in syngeneic mice, high producer clones undergo complete rejection due to the combined action of CD8+ lymphocytes, NK cells, and neutrophils. After this rejection, mice are immune to a subsequent challenge with TSA-pc. This memory rests on a strong lytic activity of CD8+ CTL and granulocytes. Following the rejection, mice also develop anti-TSA Ab that guide the granulocytes in TSA-pc memory reaction. A direct comparison shows that although TSA clones engineered to release IL-2 activate CTL and no anti-TSA Ab, those engineered to release IL-4 activate a strong Ab response but not CTL. The kind of cytokine released by the tumors appears to determine the type of response. However, IL-10 high producer cells do not deviate the immune memory, neither toward a Th1 nor a Th2. Both the CTL activity and the Ab responses induced by IL-10 high producer cells are the strongest so far observed in the TSA system.

Transduction of genes coding for a histocompatibility (MHC) antigen and for its physiological inducer interferon-gamma in the same cell: efficient MHC expression and inhibition of tumor and metastasis growth

The mouse mammary carcinoma TS/A, of BALB/c (H-2d) origin, was transfected with the murine interferon-gamma (IFN-gamma) gene (Int. J. Cancer 55: 320, 1993). We used IFN-gamma transfectants as recipients for a second round of transfections with murine allogeneic class I histocompatibility (H-2b) genes that are modulated by IFN. Transfectants with either gene alone, as well as parent TS/A cells (TS/A-pc), were used as controls. Only double transfectants expressed high levels of the allogeneic H-2b genes, while in H-2b single transfectants the expression was very low (but was induced by treatment with exogenous IFN-gamma). The tumorigenic potential of IFN-gamma or H-2b single transfectants was reduced in comparison to TS/A-pc. IFN-gamma+H-2Kb double transfectants were almost nontumorigenic, while IFN-gamma+H-2Db clones gave rise to tumors in about one-half of mice. The experimental metastatic ability of all IFN-gamma+H-2b double transfectants was very low. IFN-gamma single transfectants were known to induce a strong macrophage response in the host. The expression of allogeneic H-2 antigens added a T-lymphocyte-mediated response that accounted for the lower tumorigenicity of double transfectants. These results show that it is possible to steer the immune response evoked by tumor cells for therapeutic purposes. Moreover, the high H-2 expression obtained in IFN-gamma+H-2b double transfectants suggests that single IFN-gamma transfectants are ideal recipients for all IFN-sensitive genes. This approach can be used also for other general-purpose inducers of gene expression.

5-Fluorocytosine-induced eradication of murine adenocarcinomas engineered to express the cytosine deaminase suicide gene requires host immune competence and leaves an efficient memory

The nonmammalian cytosine deaminase (CD) enzyme converts the nontoxic prodrug 5-fluorocytosine (5-FC) to the toxic metabolite 5-fluorouracil. Parental cells of a mammary adenocarcinoma (TSA-pc) of BALB/c mice were transfected with the CD gene (TSA-CD), and the ability of 5-FC to hamper their growth was evaluated. A quantity amounting to 0.5 mg of 5-FC/0.3 ml of medium inhibits the proliferation of TSA-CD cells, but not that of TSA-pc, nor that of TSA-pc transfected with neomycin-resistance gene only (TSA-neo). In BALB/c mice, 800 mg 5-FC/kg of body weight injected daily i.p. for 30 days causes total regression of incipient (1-day-old), and established (3- and 7-day-old) TSA-CD tumors, and of 3-day-old experimental lung metastases, but does not impair TSA-pc nor TSA-neo cell growth. Because in CD8+ T lymphocyte- and granulocyte-depleted mice 5-FC no longer impairs TSA-CD growth, immune mechanisms appear to play an important role in this regression. Following, regression, all mice are resistant to subsequent s.c. or i.v. lethal challenges with TSA-pc. The induction of this immune memory is dependent on CD4+ lymphocytes, whereas its effector phase depends on both CD4+ and CD8+ lymphocytes. The memory elicited in tumor-bearing mice by the 5-FC-dependent regression of TSA-CD tumors cures a significant number of mice with 4-day-old TSA-pc metastases, but does not impair the growth of 4-day-old solid s.c. tumors. The reliability of this regression and the subsequent establishment of an efficient immune memory against poorly immunogenic TSA-pc offer the prospect that CD-transduced tumor cells and 5-FC can be used as components of a live antitumor vaccine.

5-Fluorocytosine-induced eradication of murine adenocarcinomas engineered to express the cytosine deaminase suicide gene requires host immune competence and leaves an efficient memory

The nonmammalian cytosine deaminase (CD) enzyme converts the nontoxic prodrug 5-fluorocytosine (5-FC) to the toxic metabolite 5-fluorouracil. Parental cells of a mammary adenocarcinoma (TSA-pc) of BALB/c mice were transfected with the CD gene (TSA-CD), and the ability of 5-FC to hamper their growth was evaluated. A quantity amounting to 0.5 mg of 5-FC/0.3 ml of medium inhibits the proliferation of TSA-CD cells, but not that of TSA-pc, nor that of TSA-pc transfected with neomycin-resistance gene only (TSA-neo). In BALB/c mice, 800 mg 5-FC/kg of body weight injected daily i.p. for 30 days causes total regression of incipient (1-day-old), and established (3- and 7-day-old) TSA-CD tumors, and of 3-day-old experimental lung metastases, but does not impair TSA-pc nor TSA-neo cell growth. Because in CD8+ T lymphocyte- and granulocyte-depleted mice 5-FC no longer impairs TSA-CD growth, immune mechanisms appear to play an important role in this regression. Following, regression, all mice are resistant to subsequent s.c. or i.v. lethal challenges with TSA-pc. The induction of this immune memory is dependent on CD4+ lymphocytes, whereas its effector phase depends on both CD4+ and CD8+ lymphocytes. The memory elicited in tumor-bearing mice by the 5-FC-dependent regression of TSA-CD tumors cures a significant number of mice with 4-day-old TSA-pc metastases, but does not impair the growth of 4-day-old solid s.c. tumors. The reliability of this regression and the subsequent establishment of an efficient immune memory against poorly immunogenic TSA-pc offer the prospect that CD-transduced tumor cells and 5-FC can be used as components of a live antitumor vaccine.

Systemic effects of cytokines released by gene-transduced tumor cells: marked hyperplasia induced in small bowel by gamma-interferon transfectants through host lymphocytes

Cells transduced with cytokine genes are currently used to enhance the anti-tumor and immunomodulatory effects of these molecules in cancer therapy. The sustained release of cytokine thus obtained can perturb many homeostatic systems of the host. We have previously shown that the murine mammary adenocarcinoma TS/A transfected with the murine gamma-interferon (IFN-gamma) gene stimulates a strong immune response that impairs tumor growth. Mice bearing tiny tumors have serum IFN-gamma levels constantly exceeding 100 IU/ml. Therefore, we asked which systemic effects can be triggered in mice by such transfectants. BALB/c mice bearing tumors produced by clone 16.6000 cells (which release 6,000 IU/ml of IFN-gamma in culture) were compared to normal mice and to mice with tumors produced by parent cells transfected with the neomycin resistance gene (NEO cells, no IFN-gamma release). Histological studies revealed a marked hyperplasia of small bowel in mice bearing 16.6000 tumors; the villi and crypts of these mice were > 1.5 times longer than those of normal mice and of mice bearing NEO tumors. In vivo administration of bromodeoxyuridine evidenced a 2.5-3 times increase in the proliferative score of the intestinal crypts of mice bearing 16.6000 tumors compared to control mice. No intestinal alterations were observed in nude mice bearing 16.6000 tumors. T lymphocytes thus appear to play a causal role in this phenomenon.

Co-expression of B7-1 and ICAM-1 on tumors is required for rejection and the establishment of a memory response

Although the transfection of B7-1 cDNA into a few mouse tumor cell lines can induce anti-tumor T cell immunity, its expression alone is ineffective in many other tumor cell lines tested. We were interested to study what factors limit B7-1 co-stimulatory activity, and decided to investigate whether B7-1 requires the cooperation of ICAM-1 to provide the minimal co-stimulatory signal for establishing an efficient anti-tumor immunity. We show that the transfection of B7-1 cDNA into three ICAM-1+ (plasmocytoma J558L, T lymphomas EL-4 and RMA), but not into two ICAM-1- tumors cell lines (adenocarcinoma TS/A and melanoma B16.F1), is sufficient to induce their complete rejection in syngeneic mice. The expression of ICAM-1 is necessary for the rejection of the B7 expressing tumors, since the primary response elicited by B7-1+ EL-4 and RMA clones expressing reduced levels of ICAM-1 is severely reduced. Furthermore, super-transfection of ICAM-1 cDNA into B7-1+ adenocarcinoma and melanoma clones optimizes their primary rejection. Histologic examination of transfected tumors reveals that B7-1 and ICAM-1 exert a potent pro-inflammatory activity. The intra-tumor infiltration is composed of both eosinophils and lymphomonocytes, and is already massive 5 days after the tumor challenge. The primary rejection of the B7-1+ ICAM-1+ tumors depends critically on CD8+ T cells, natural killer cells and granulocytes, but is independent of CD4+ T cells. Remarkably, in addition to its effects on the early phases of the immune response, the co-expression of ICAM-1 and B7-1 on tumors is also necessary for the efficient induction of a memory response. In fact, only the primary challenge with B7-1+, ICAM-1+ tumor cells protects the majority of the mice from a second injection of parental tumor cells. Collectively, our findings indicate that B7-1 and ICAM-1 are fundamental components for triggering the primary rejection of tumors and establishing a protective memory response. These findings may help to define new strategies for the rational application of co-stimulation in tumor immunotherapy.

Moderate alcohol consumption and spontaneous abortion

A prospective study was carried out on 546 women interviewed during pregnancy about their drinking habits, in order to evaluate the association between alcohol consumption during pregnancy and spontaneous abortion. Pregnancy outcome (normal or abortion) was analysed as a dependent variable in a multivariate model where different levels of drinking were taken into consideration as independent-effect variables. A significant increase in the risk of abortion was observed in the 30+ age category and in the higher parity category; no significant trend was evidenced for alcoholic variables, even after controlling for the other potentially confounding variables. The possible underestimation of alcohol consumption, due to reluctance in declaring real consumption by the women interviewed, is discussed. It is concluded that, on the basis of these and other data reported in the literature, a low level of alcohol consumption during pregnancy does not appear to be a significant risk for abortion.

An efficient Th2-type memory follows CD8+ lymphocyte-driven and eosinophil-mediated rejection of a spontaneous mouse mammary adenocarcinoma engineered to release IL-4

A retroviral infection was used to introduce the cDNA coding for mouse IL-4 into the parental cells of a spontaneous adenocarcinoma of BALB/c mice (TS/A-pc). Four clones releasing between 5 to 40 U of IL-4 (10(5) cells) in 48 h culture were selected. The secretion of IL-4 does not affect their in vitro growth, whereas their ability to form tumor in vivo inversely correlates with the amount of IL-4 secreted. Although morphologic observation suggested that the rejection of clone D5.40 cells (releasing 40 U of IL-4) depends on eosinophil cytolysis, lymphocyte depletion experiments showed that this required CD8+ lymphocyte guidance. Mice that had rejected D5.40 cells were immune to a subsequent challenge with TS/A-pc. This memory rests on the interaction between noncytotoxic lymphocytes, eosinophils, and IgG1 and IgE anti-TS/A Abs. Comparison of these memory mechanisms with those elicited by IL-2 gene-transduced TS/A cells shows that the kind of cytokine released by the tumor cells determines the type of response. This Th2 memory seems to be more efficient in protecting against a subsequent challenge of TS/A-pc than the Th1-type memory elicited by IL-2 gene-transduced TS/A cells.

An efficient Th2-type memory follows CD8+ lymphocyte-driven and eosinophil-mediated rejection of a spontaneous mouse mammary adenocarcinoma engineered to release IL-4

A retroviral infection was used to introduce the cDNA coding for mouse IL-4 into the parental cells of a spontaneous adenocarcinoma of BALB/c mice (TS/A-pc). Four clones releasing between 5 to 40 U of IL-4 (10(5) cells) in 48 h culture were selected. The secretion of IL-4 does not affect their in vitro growth, whereas their ability to form tumor in vivo inversely correlates with the amount of IL-4 secreted. Although morphologic observation suggested that the rejection of clone D5.40 cells (releasing 40 U of IL-4) depends on eosinophil cytolysis, lymphocyte depletion experiments showed that this required CD8+ lymphocyte guidance. Mice that had rejected D5.40 cells were immune to a subsequent challenge with TS/A-pc. This memory rests on the interaction between noncytotoxic lymphocytes, eosinophils, and IgG1 and IgE anti-TS/A Abs. Comparison of these memory mechanisms with those elicited by IL-2 gene-transduced TS/A cells shows that the kind of cytokine released by the tumor cells determines the type of response. This Th2 memory seems to be more efficient in protecting against a subsequent challenge of TS/A-pc than the Th1-type memory elicited by IL-2 gene-transduced TS/A cells.

Immunizing and curative potential of replicating and nonreplicating murine mammary adenocarcinoma cells engineered with interleukin (IL)-2, IL-4, IL-6, IL-7, IL-10, tumor necrosis factor alpha, granulocyte-macrophage colony-stimulating factor, and gamma-interferon gene or admixed with conventional adjuvants

To evaluate the efficacy of vaccinations with cytokine-gene-transduced tumor cells, BALB/c mice were challenged with 1 x 10(5) parental cells of a syngeneic adenocarcinoma cell line (TSA-pc). No protection was observed in mice immunized 30 days earlier with 1 x 10(5) nonreplicating mitomycin-C-treated TSA-pc alone, or with Corynebacterium parvum or Complete Freund Adjuvant (CFA). Ten to 30% of mice immunized with nonreplicating cells engineered to produce interleukin (IL)-2, IL-4, IL-6, IL-7, IL-10, tumor necrosis factor alpha, granulocyte-macrophage colony-stimulating factor, and gamma-interferon gene were protected. Fifty % of mice immunized with replicating TSA-pc admixed with C. parvum and 80-100% of mice immunized with replicating tumor cells transduced with IL-2, IL-4, IL-7, IL-10, or gamma-interferon gene were protected. No cure was afforded by TSA cells admixed with C. parvum or CFA, nor by TSA cells engineered with IL-6, granulocyte-macrophage colony-stimulating factor, and tumor necrosis factor alpha gene injected starting 1 day after TSA-pc challenge. Complete tumor regression, however, was obtained in 10-20% of mice treated with TSA cells transduced with IL-2, IL-4, IL-7, or IL-10 and in 30% of those treated with TSA cells transduced with gamma-interferon gene.