Role of immunosuppression in recurrence after liver transplantation for diethylnitrosamine-induced tumors in rats

Hepatocellular carcinoma is one of the world's most common malignant diseases, with an increasing incidence related to liver cirrhosis. The purpose of the study was to evaluate the role of immunosuppression in recurrence in rats transplanted after liver tumor induction by diethylnitrosamine (DENA), which has proved to be a reliable carcinogen. In 14-week-old Lewis rats weighing 200 g, tumors were induced by the oral administration (5 mg/100 ml in drinking water ad libitum) of DENA for 13 weeks. Orthotopic liver transplantation (OLT) was performed after 4 weeks' latency. In the Lewis/Lewis rats weighing 200 g, tumors sporin A (CsA) treatment, median survival was 199-days with no recurrence or metastasis. In the BN/Lewis group with no CsA (5 ats) median survival was 144 days. All rats died due to rejection. In the other BN/Lewis group (10 rats), OLT was followed by CsA administration (7.5 mg/kg). Median survival was 161 days. In three rats (218 days), there was liver tumor recurrence; in two rats (137.5 days), kidney and lung metastases were found. The remaining rats died of septic complications. In the Lewis/Lewis + CsA group (10 rats), median survival was 131 days with 5 recurrencies and/or metastases. Two rats are still surviving at 84 and 88 days. Our results suggest that the DENA model is reliable; it proved to have a similar carcinologic pattern to HCC in man. Moreover, immunosuppression seems to play an important role in determining recurrence. Further studies are needed to investigate the efficacy of chemotherapy agents pre- and post-transplantation.

Opioid dysregulation after biliopancreatic diversion: effect of naloxone on preprandial and postprandial growth hormone (GH)-releasing hormone-induced GH release in surgically induced weight loss

Previously, we have shown that in the opposite extremes of nutritional status (obesity and anorexia nervosa [AN]), the growth hormone (GH) response to GH-releasing hormone (GHRH) is not inhibited by the ingestion of a normal 800-kcal meal at noon. In obese subjects, GHRH-induced GH release is significantly increased (known as the "paradoxical response"). An opiate antagonist infusion (naloxone [NAL]) inhibited this postprandial meal-induced augmenting effect in obese subjects, suggesting opioid involvement in the paradoxical response. The paradoxical postprandial GH release persisted in obese subjects, who after biliopancreatic diversion (BPD) experienced a reduction in body weight, despite the elevation of fasting GH levels. We therefore tested a group of patients, before and after BPD, composed of 10 females, aged 23 to 54 years, who after surgery had experienced a significant reduction in body weight (mean body mass index [BMI], 25.78 +/- 1.01 kg/mg v 44.68 +/- 1.73 kg/mg). The subjects were studied 16 to 24 months after operation, in a phase of stabilized body weight. They underwent, in randomized order, the following tests: GHRH (1 microg/kg as an intravenous [IV] bolus) at 1:00 PM, in the fasting state; GHRH (1 microg/kg) at 1:00 PM, 45 minutes after a standard 800-kcal meal consumed between noon and 12:15 PM; and fasting state and postprandial GHRH (1 microg/kg) during NAL infusion (1.6 mg/h x 2.5 h, starting at noon). We found that NAL inhibited the paradoxical postprandial GH increase only in pre-BPD subjects (GH area under the concentration time curve [AUC] in microg/L/90 min)-before meal: after GHRH 237.54 +/- 62.28, after NAL + GHRH 699.2 +/- 271.57; after meal: after GHRH 575.46 +/- 109.68, after NAL + GHRH 156.17 +/- 24.96. On the other hand, NAL failed to have significant effects in post-BPD subjects (GH AUC in microg/L/90 min)-before meal: after GHRH 871.11 +/- 256.38, after NAL + GHRH 449.19 +/- 119.13; after meal: after GHRH 1,981.54 +/- 319.92, after NAL + GHRH 1,665.91 +/- 315.4. It could be hypothesized that the opioid system is radically modified by the surgical procedure, and that opioids are not the only mediators in the paradoxical response, which persists after BPD, despite the reversion of the hyposecretory GH state, which is a characteristic of obese subjects.

Effect of feeding on growth hormone response to growth hormone-releasing hormone in polycystic ovarian syndrome: relation with body weight and hyperinsulinism

The plasma growth hormone (GH) response to direct stimulation with growth hormone-releasing hormone (GHRH) before and after a standard meal was investigated in 14 polycystic ovarian syndrome (PCOS) subjects. Data were compared with those obtained from 14 healthy normovulatory matched patients. All women underwent an oral glucose tolerance test (OGTT) (75 g) and basal plasma hormone concentrations were evaluated. On a different day all subjects had a GHRH test (50 microg GHRH) both before and after lunch randomly. In obese PCOS subjects the GH response to GHRH was blunted after a meal, while in obese control patients there was an enhanced response of GH to GHRH after a meal. Normal control subjects showed an inhibition of the GH response after feeding and lean PCOS subjects showed a trend toward an augmented GHRH related secretion after a meal significantly higher than normal controls (P < 0.05) but not significantly higher than the pre-prandial response. In conclusion, the data indicate in PCOS a derangement of GH secretion related to food ingestion; in particular obese PCOS patients did not exhibit any change of GH response after a meal compared with the paradoxical response observed in obese controls. Several other factors beyond body mass index and hyperinsulinism could be involved in these pathophysiological events.

Bronchoscopically-guided conformal radiation therapy for radiographically occult lung carcinoma

Radiographically occult lung carcinoma has a very good prognosis after complete surgical resection. In medically inoperable patients three-dimensional conformal radiation therapy cannot be performed, as computed tomography scan images fail to localize the disease. Presented here is an original technique of marking radiographically occult tumors by fiberoptic bronchoscopy, applied on four patients. No short-term complications were recorded. All the patients are alive, with no evidence of disease, after a mean follow-up of 15 months.

Src homology 2-containing inositol 5-phosphatase 1 binds to the multifunctional docking site of c-Met and potentiates hepatocyte growth factor-induced branching tubulogenesis

Hepatocyte growth factor (HGF)/scatter factor is a multifunctional cytokine that induces mitogenesis, motility, and morphogenesis in epithelial, endothelial, and neuronal cells. The receptor for HGF/scatter factor was identified as c-Met tyrosine kinase, and activation of the receptor induces multiple signaling cascades. To gain further insight into c-Met-mediated multiple events at a molecular level, we isolated several signaling molecules including a novel binding partner of c-Met, SH2 domain-containing inositol 5-phosphatase 1 (SHIP-1). Western blot analysis revealed that SHIP-1 is expressed in the epithelial cell line, Madin-Darby canine kidney (MDCK) cells. SHIP-1 binds at phosphotyrosine 1356 at the multifunctional docking site. Because a number of signaling molecules such as Grb2, phosphatidylinositol 3-kinase, and Gab1 bind to the multifunctional docking site, we further performed an in vitro competition study using glutathione S-transferase- or His-tagged signaling molecules with c-Met tyrosine kinase. Our binding study revealed that SHIP-1, Grb2, and Gab1 bound preferentially over phosphatidylinositol 3-kinase. Surprisingly, MDCK cells that overexpress SHIP-1 demonstrated branching tubulogenesis within 2 days after HGF treatment, whereas wild-type MDCK cells showed tubulogenesis only after 6 days following treatment without altering cell scattering or cell growth potency. Furthermore, overexpression of a mutant SHIP-1 lacking catalytic activity impaired HGF-mediated branching tubulogenesis.

Use of self-expanding metal stents for palliation of rectosigmoid cancer

BACKGROUND

Patients with large bowel obstruction can be palliated by colostomy or by endoscopic modalities that restore luminal patency. The clinical results of a series of patients with rectosigmoid cancer in whom self-expanding metal stents were inserted at endoscopy are presented.

METHODS

Thirty-seven patients with symptoms related to obstructive rectosigmoid adenocarcinoma were treated by endoscopic insertion of self-expanding metal stents.

RESULTS

Metal stents were correctly placed in 36 of 37 patients (97%) with no immediate complications. Early dislodgment of the stent (within 1 week) was observed in 3 cases. The remaining 33 patients (92%) were followed for a median of 7 months (3 weeks-33 months). In 28 patients (78%) there was long-term restoration of luminal patency and disappearance of obstructive symptoms without further treatments. They experienced no pain, tenesmus, or incontinence during the follow-up period. The incidence of complications (early and late) and the mortality rate related to the procedure were 22% and 3%, respectively.

CONCLUSIONS

Endoscopic metal stents can be considered a simple and effective solution for long-term palliation of rectosigmoid cancer.

The direct association of the multiple PDZ domain containing proteins (MUPP-1) with the human c-Kit C-terminus is regulated by tyrosine kinase activity

We have identified the multiple PDZ domain containing protein (MUPP-1 or MPDZ) as a novel binding partner of the human c-Kit. c-Kit binds specifically to the 10th PDZ domain of MUPP-1 via its C-terminal sequence. Furthermore, a kinase negative-mutant receptor interacted more strongly with MUPP-1 than the wild-type c-Kit. Strikingly, a constitutively activated c-Kit (D816V-Kit) did not bind to MUPP-1, although this oncogenic form retains the PDZ binding motif 'HDDV' at the C-terminal end. Deletion of V967 of c-Kit abolished binding to MUPP-1 and drastically reduced its tyrosine kinase activity, suggesting that the structure of the C-terminal tail of c-Kit influences its enzymatic activity.

Expression of p21 in non small cell lung cancer relationship with PCNA

The first cyclin dependent kinase inhibitor to be discovered was the p21 cdk interacting protein (a.k.a., WAF1, Cip1, CAP20, Sdi1, mda6). p21 expression may or may not be dependent on p53. This pathway also inhibits DNA replication by merit of p21's interaction with PCNA, but it has also been shown that this same inhibitory interaction with p21 does not affect PCNA DNA repair abilities. We assessed the immunohistochemical expression of p21 protein in 60 curative surgical resected non small cell lung cancers relating it to the expression of PCNA to clarify the contribution of the p21/PCNA pathway to the development of NSCLC. We did not find any relationship between PCNA and p21 expression. This last result may indicate that the mechanism by which PCNA controls the DNA repair is the most important activity of this protein during lung cancer progression and development, compared to its contribution to cell proliferation. In fact, this last event is strongly counteracted by p21 expression, which in this last case works as an inhibitor of PCNA expression. In conclusion this study highlighted the important role of the p21/PCNA pathway in lung carcinogenesis, pointing out the contribution of PCNA to the response to lung aggression and not only it's role as a proliferation index. Therefore, these results offer a background to further study to evaluate potential novel therapeutic approaches to lung cancer treatment.

Echobiometry of the ocular layers at the posterior pole

The thickness of the retina, choroid and sclera in relation to macular oedema (ME) can be measured using A scan echography. Ninety diabetic patients (180 eyes) divided into two groups with and without ME, respectively, were studied compared to a third group of 73 healthy controls (146 eyes). Statistical analysis of results showed good specificity (80%) and reasonable sensitivity (70%) of the echographic method in showing the presence of ME confirmed by fluorescein angiography.

A case of quiescent choroidal melanoma: early echographic signs of reactivation

A medium-sized choroidal melanoma was studied during a 5-year phase of remission. The tumour presented signs of reactivation with changes in the echographic features without a significant increase in size. The echographic signals in the reactivation phase and the echographic evolution after treatment are described.

Congenital retinoblastoma: appearance of calcifications during short-term follow-up

An echographic follow-up of a case of congenital retinoblastoma was performed by monitoring variations in the tumoral echostructure concomitant with the appearance of microcalcifications. A previously unreported echo-graphic aspect regarding the first phase of observation is described. The calcifications in the tumour were evidenced on the 41st day of the patient's life.

p53, cyclin-D1, PCNA, AgNOR expression in squamous cell cancer of the lip: a multicenter study

BACKGROUND

The development of squamous cell carcinoma of the lower lip is an interesting model of photocarcinogenesis because of the structural and topographic characteristics of the lips. The purpose of this study was to evaluate the expression of immunohistochemical markers on the lips of patients with lower lip squamous cell carcinoma (LLSCC), compared with a control population.

METHODS

Of the 98 subjects involved in the study, 58 were suffering from squamous cell carcinoma of the lower lip. The remaining 40 acted as a control. The case studies were taken from six university and hospital dermatology and plastic surgery departments. Questionnaires were administered to assess the risk factors for LLSCC. The cases involving squamous cell carcinoma underwent surgical excision and punch biopsy specimens were obtained from 20 control patients. Tissues were prepared in 5-microm-thick sections to carry out the following immunohistochemical study: PCNA, p53, AgNOR, cyclin-D1, bcl-2.

RESULTS

The lower lip was the predominant location of squamous cell carcinoma, with the following factors playing important roles: chronic sun exposure, history of smoking, alcohol use and familial risk of cutaneous tumors. The male/female ratio in our survey was 5:1. The p53 protein was positive in approximately 50% of SCC cases and in 20% of controls. This protein is mostly associated with chronically photoexposed skin areas. AgNOR positivity increased with the loss of cellular differentiation; a progressive increase in size and a poorly defined shape were evident in poorly differentiated carcinomas.

CONCLUSIONS

The results of this multicenter study showed that there is a noticeable difference in the expression of PCNA, p53, cyclin-D1, and AgNOR in tissues from patients with LLSCC and controls.

Inhibitory action on GHRH-induced GH secretion of chronic tamoxifen treatment in breast cancer

OBJECTIVE

Previous in vitro and in vivo studies on animal models have demonstrated that tamoxifen (TAM) inhibits GH secretion. Studies in humans are conflicting. The aim of this study was to evaluate the effect of chronic TAM treatment on GH secretory dynamics in the presence of negligible endogenous oestrogens, in postmenopausal women with breast cancer.

PATIENTS

Ten female patients were studied over a 6-12-month period after surgical therapy, before medical therapy, and during chronic treatment with TAM (20 mg/day p.o.).

MEASUREMENTS

In all subjects we performed a standard GHRH-test (50 mg i.v. as a bolus) and compared the single time points, the peak response and the areas under the curves (AUC), before and during treatment. In basal samples, we evaluated the circulating levels of IGF-1, IGF-BP3 and their ratio, SHBG, FSH, LH, Oestradiol (E2) and PRL. GH was assayed by Immunoradiometric assay (IRMA). Insulin-like growth factor type I (IGF-I), Insulin-like growth factor-binding protein-3 (IGF-BP3), FSH, LH and PRL were measured by Radioimmunoassay (RIA). SHBG was measured by a noncompetitive liquid phase immunoradiometric assay, while E2 was measured directly in plasma by a liquid phase technique.

RESULTS

TAM chronic treatment significantly reduced GH response to GHRH at single time point evaluations, GH peak response (mean decrease: 59.8 +/- 7.3%) and GH-AUC (mean decrease 53.8 +/- 8.9%). TAM also significantly reduced plasma IGF-1 levels. No significant variations were found in IGF-BP3 levels or in the IGF-1/IGF-BP3 ratio. A significant inverse correlation between SHBG and IGF-1 circulating levels was noticed during TAM treatment.

CONCLUSIONS

Our data show that long-term tamoxifen treatment blocks the response of GH to exogenous GHRH and reduces IGF-1 levels, possibly by a central mechanism other than the demonstrated peripheral action. The results of this study, keeping in mind the demonstrated mitogenic role of IGF-1 in cancer proliferation, can contribute to clarify the mechanism by which TAM exerts its antiproliferative effect.

A conditioned medium from a human liposarcoma-derived cell line induces p53-dependent apoptosis in several tumor cell lines

A novel cell line, named LSA, has been obtained, stabilized, and characterized from a human liposarcoma. These cells have morphological and biochemical features strongly resembling the adipocytes and were able to grow in the Ham's F12 medium, in presence or absence of FCS. A conditioned medium (LSA-CM) was obtained by growing the LSA cells in the F12 medium in the absence of FCS. LSA-CM had cytostatic and cytotoxic effects (apoptosis and necrosis) associated with down-regulation of c-myc and upregulation of p53 in several human cell lines (breast, lung, glioblastoma, etc. ). The MCF-7 and glioblastoma cells were killed by LSA-CM in 5-6 days, whereas the same cells were killed by LSA-CM co-incubated with low doses of cisplatin in 30 h. LSA-CM peri-tumoral injections for 15 days in Balb-c-fc3H mice affected by mammary tumors, resulted in the rapid disruption of tumors and absence of metastases. In contrast, in the untreated animals the tumor masses were 4 times larger than initial lesions, and numerous metastases were found in the lungs. The toxicity analysis of LSA-CM, performed on three different animal species, showed that LSA-CM is absolutely free of acute, subacute, and subchronic toxicity. The possible use of LSA-CM/cisplatin for cancer treatment is discussed.

Percutaneous implantation of a catheter with subcutaneous reservoir for intraarterial regional chemotherapy: technique and preliminary results

PURPOSE

We present the technique and the preliminary results of percutaneous implantation of intraarterial catheters connected to a subcutaneous infusion reservoir for prolonged regional chemotherapy of hepatic and extrahepatic tumors.

METHODS

Two hundred patients with primary or secondary hepatic neoplasms, pelvic, pancreatic, renal, lingual, and breast cancer underwent the procedure. The access was the left axillary artery (188 patients) and the femoral artery (12 patients). The catheter tip was placed in the hepatic (170 patients), hypogastric (18), splenic (4), internal thoracic (2), gastroduodenal (3), renal (2) or the external carotid artery (1). The catheter was connected to a subcutaneous reservoir and filled with heparin; chemotherapeutic infusion was subsequently started.

RESULTS

One hundred percent immediate technical success was obtained. Forty-three of 200 (21.5%) patients had a complication: 29 patients had a catheter dislodgment, nine had arterial thrombosis, three had a pseudoaneurysm of the left axillary artery and two had a port pocket hematoma. Most complications (37/43, 86%) were treated percutaneously without interruption of chemotherapy. In only six cases (3% of the total population) was chemotherapy discontinued due to the complication itself. The mean duration of catheter patency was 7.2 months.

CONCLUSION

Percutaneous placement of an intraarterial catheter is feasible and causes less discomfort to the patient than the surgical approach. The technique has an acceptable complication rate (21.5%), similar to that for surgical implantation (17.8%), with the advantage that in most cases the complications can be resolved percutaneously. This technique represents an alternative to surgical implantation in the treatment of liver metastases from colorectal cancer and opens new therapeutic possibilities for the local prolonged treatment of other kinds of tumor, though its clinical efficacy must be assessed in selected trials.

Role of food intake in the modulation of hexarelin-induced growth hormone release in normal human subjects

Hexarelin (HEX) is a new synthetic analog of the Growth Hormone releasing peptides and is stronger than GHRH in releasing GH in vivo. No information is available on the effect of food ingestion on HEX-induced GH secretion. On the other hand, we have previously demonstrated that food intake at lunchtime in normal subjects has an inhibitory effect on the GH response to GHRH. The aim of the present study was to investigate the effect of food ingestion on GH secretion induced by HEX as compared to GHRH in six normal men (aged 23-29 years) and six normal women (aged 24-29 years). The body weights for all subjects were within 120% of their ideal body weight, according to their sex and age. Our data confirm that HEX is much more powerful than GHRH in inducing GH release in humans, both in the fasting state (GH-AUC: 3010 +/- 695 after HEX, vs. 1339 +/- 281 after GHRH, microg/L/120 min; p<0.06) and after a meal (GH-AUC: 1523 +/- 121, after HEX, vs. 309 +/- 61, after GHRH, microg/L/120 min; p<0.06). Moreover, our study shows that food intake partially blunts the fasting GH response to HEX (GH-AUC: 3010 +/- 695 after HEX, in fasting state, vs. 1523 +/- 121 after HEX, after meal, microg/L/120 min; p<0.06; mean inhibition of AUC 41.02 +/- 7.96%), whereas it nearly abolishes the GH response to GHRH in the same subjects (GH-AUC: 1339 +/- 281 after GHRH, in fasting state, vs. 309 +/- 61 after GHRH, after meal, microg/L/120 min; p<0.06; mean inhibition of AUC 70.31 +/- 6.22%). In conclusion, our study confirms that HEX acts differently from GHRH; the GH releasing effect of HEX could be only partially influenced by the physiological metabolic or neuroendocrine food-related modifications.

Direct interaction of nerve growth factor receptor, TrkA, with non-receptor tyrosine kinase, c-Abl, through the activation loop

The nerve growth factor receptor, TrkA, is essential for the survival and differentiation of neurons in the central and peripheral nervous systems. To understand the molecular principles underlying this differentiation step, we employed a yeast two-hybrid screening protocol using human TrkA as bait. We isolated c-Abl as a TrkA-interacting protein, in addition to known proteins such as phospholipase Cgamma and SH2-B. This interaction was confirmed by an in vitro binding assay using glutathione S-tranferase-Abl fusion protein. Furthermore, we show here that c-Abl binds to phosphotyrosine residue(s) in the kinase activation loop of TrkA.

Effects of galanin on growth hormone and prolactin secretion in anorexia nervosa

Galanin (GAL) elicits growth hormone (GH) release in normal subjects through interaction with hypothalamic somatostatin. GAL also stimulates GH-releasing hormone (GHRH) secretion in vitro. In rats, GAL is able to stimulate prolactin (PRL) release, but this effect is not clear in humans. We have thus investigated GAL effects on GH and PRL release in patients with anorexia nervosa (AN), known to have altered regulation of the GH-insulin-like growth factor axis and PRL dynamics, and compared the effects of GHRH and GAL on GH and PRL secretion in AN and normal healthy subjects. Eight women with AN (15 to 27 years; body mass index [BMI], 17 to 19.5 kg/m2) were treated with (1) GHRH 50 microg intravenous (IV) injection, (2) porcine GAL 500 microg infusion from -10 to +30 minutes, and (3) 135-minutes saline infusion as a control, respectively. Both peptides induced a significant increase in plasma GH in AN patients (peak level, 27.41 +/- 5.50 microg/L after GAL and 18.97 +/- 2.67 microg/L after GHRH). When data for AN patients and the control group were compared, GH peak levels after GAL were significantly higher in AN patients (27.41 +/- 5.50 v 13.64 +/- 2.32 microg/L), while GH peak levels after GHRH were not different between the 2 groups (18.97 +/- 2.67 v 15.98 +/- 3.88 microg/L). PRL levels significantly increased after both GHRH (peak, 11.70 +/- 2.80 microg/L) and GAL (peak, 18.02 +/- 5.10 microg/L) treatment in AN patients, but not in normal subjects. We conclude that GAL stimulates exaggerated GH release in AN patients as compared with normal controls, suggesting a dual hypothalamic interaction via both an increase in endogenous GHRH and a decrease in somatostatin secretion. Finally, GAL may act as a PRL secretagogue in AN patients.