Effect of the somatostatin analog, octreotide, and of other hormones on the release of the acid-labile subunit of the 150 kDa complex by rat hepatocyte in primary culture

IGF-I, IGF-II, IGFBP2, IGFBP3 and acid-labile subunit (ALS) in colorectal cancer patients before surgery and during one year follow up in relation to age

PURPOSE

To investigate the changes of IGF system in colon cancer patients in relation to age, the serum IGF-I, IGF-II, IGFBP2, IGFBP3 and ALS were measured by immunochemistry before surgery, as well as one and six months after surgery.

MATERIAL AND METHODS

One hundred and twenty six patients were included into the study: group I (<50 yrs, N=21); group II (50 to <55 yrs, N=16) ; group III (55 to <65 yrs, N=34); group IV (65 to <75 yrs, N=42) and group V (> or =75 yrs, N=13).

RESULTS

Before surgery: only the mean value of IGF-I concentration in group I was significantly higher as compared to group V (p<0.01). One month after surgery: 1) a decrease in the mean values of IGF-I, IGF-II, IGFBP3 and ALS levels was observed, but only for IGF-II (groups II-V), IGFBP3 (groups II-V) and ALS (groups III-V) the changes were significant; 2) the mean value of ALS level in group I was higher as compared to group III-V (p<0.05 to 0.02); 3) higher mean values of IGF-I/alb, IGFBP3/alb and ALS/alb were noted for group I as compared to group V (p<0.01 to 0.001); 4) the mean levels of IGFBP2 were significantly lower in group I as compared to groups II, III, IV and V (p<0.001 in all cases).

CONCLUSIONS

In colon cancer patients IGF-I, IGFBP3 and ALS decrease with age, but the relation between them exists regardless the patient's age and time of observation. Lower IGFBP2 level together with higher IGF-I might contribute to more aggressive course of disease in colon cancer patients below 50 years of age.

Efficacy of a slow-release formulation of lanreotide (Autogel) 120 mg) in patients with acromegaly previously treated with octreotide long acting release (LAR): an open, multicentre longitudinal study

OBJECTIVE

Lanreotide Autogel 120 mg (ATG120; Ipsen S.p.A, Milan, Italy) is a high-dose, sustained-release aqueous gel formulation, supplied in a prefilled syringe and given by deep subcutaneous injection. The aim of this study was to compare efficacy and tolerability of ATG120 given every 4-8 weeks with those of octreotide LAR (o-LAR) given every 4 weeks. DESIGN PATIENTS AND INTERVENTION: A phase III multicentre Italian open clinical study of 23 acromegalic patients (15 female, 8 male). All patients had received o-LAR for 6-18 months and, after 3 months wash out, ATG120 was given every 6 weeks for a total of four injections (Period 1). Then the interval between ATG120 injections was adjusted according to three different schemes: every 4, 6 or 8 weeks depending on GH levels (GH > 2.5 microg/l; 1 < GH <or= 2.5 microg/l; GH <or= 1 microg/l, respectively). ATG120 was given for a further two to three doses, with a final assessment (Period 2) at Week 34, 36 or 42.

MEASUREMENTS

Hormonal (GH and IGF-I) and clinical efficacy and tolerability.

RESULTS

ATG120 induced a significant GH decrease from 9.9 +/- 11.3 at baseline (Visit 1) to 3.5 +/- 5.7 at the end of Period 1 (P < 0.01) and to 3.8 +/- 5.7 microg/l at the final visit (P < 0.01). IGF-I also decreased from 544 +/- 312 at baseline (Visit 1) to 318 +/- 181 at Period 1 and to 356 +/- 187 microg/l at the final visit (both P < 0.05 vs. baseline). The frequency of ATG120 administrations was adjusted to every 4 weeks in 12 patients, every 6 weeks in 4 patients and every 8 weeks in 6 patients; 1 patient withdrew before the dose adjustment. Serum GH and IGF-I achieved at the end of Period 1 and Period 2 were similar to those reached with o-LAR. The number of patients who achieved GH < 2.5 microg/l was comparable between o-LAR (43%) and ATG120 at Period 1 (48%) and at Period 2 (62%). Normal IGF-I levels were recorded in 8 patients during o-LAR (35%), 11 during ATG Period 1 (48%) and 10 at the final visit (43%). Last, 4 patients showed a better response to ATG120 and 2 to o-LAR.

CONCLUSIONS

Lanreotide Autogel 120 mg is an effective and well-tolerated therapy for acromegaly. In approximately half of patients ATG120 may be administered every 6-8 weeks, instead of every 4 weeks, without lost of efficacy.

Octreotide for palliative treatment of hepatic metastases from non-neuroendocrine primary tumours: evaluation of quality of life using the EORTC QLQ-C30 questionnaire

BACKGROUND AND AIM

While octreotide has been used in palliative treatment of hepatocellular carcinoma and neuroendocrine tumours with good results, little is known about the possible role of this in palliative treatment of hepatic metastases.

MATERIAL AND METHODS

We present our experience from the use of octreotide in palliative treatment of symptomatic liver metastases in 16 patients (11 males, five females, age ranged 43-69 years) with proven hepatic metastases from different primary tumours (six with non-small lung cancer, four with colon carcinoma, two with primary pancreatic head carcinoma, two with prostate cancer and two with adenocarcinoma of the stomach). All patients were administered 20 mg long-acting octreotide IM (octreotide LAR) once the first day, octreotide SC 0.5 mg three times daily on days 2-14 and then 20 mg long-acting octreotide IM every month. Quality of life was assessed by using the European Organization for Research and Treatment of Cancer (EORTC) Core Quality of Life Questionnaire (QLQ-C30). Tumour response was evaluated by using ultrasonography.

RESULTS

One month after baseline, octreotide resulted in significant (P < 0.01, Wilcoxon test) improvement and stabilization of all major related EORTC QLQ-C30 parameters such as global quality of life, pain, fatigue, insomnia, appetite loss as well as physical, emotional, cognitive, social and role functioning. Except for mild hyperglycaemia in six out of 16 patients and mild gastrointestinal complications in one patient, no other severe side effect due to octreotide was reported. Two patients died two months after the initiation of the study due to generalized metastatic disease, while the remaining 14 patients were still alive seven months after the initiation of the study. The hepatic metastases were stabilized and no new lesions were detected by ultrasonography.

CONCLUSIONS

Although further studies are warranted, we consider the use of octreotide a good alternative in palliative treatment of symptomatic liver metastases in patients with end-stage malignant disease.

Effects of a 7-day continuous infusion of octreotide on circulating levels of growth factors and binding proteins in growth hormone (GH)-treated GH-deficient patients

In patients with acromegaly, clinical improvement has been reported after octreotide (OCT) treatment, even in cases of only a moderate suppression of growth hormone (GH) levels. In rats, OCT suppresses IGF-I mRNA expression and generation of serum and tissue IGF-I levels. A direct effect of OCT on the IGF system could have therapeutical implications in diabetes mellitus, cardiovascular disease, and certain malignancies in which IGF-I might be involved. The aim of this study was to examine possible GH-independent effects of OCT on IGF components in humans. Six GH-deficient (GHD) patients were studied for 24 h after each of the following treatment regimens (each of 1 weeks duration): (a) daily s.c. GH injection (2 IU/m(2)); (b) as (a) + continuous s.c. infusion of OCT (200 microg/24 h) by means of a portable pump (Nordic Infuser); (c) no treatment. Serum GH binding protein (GHBP) levels tended to be lower after GH and OCT than after GH alone (P =0.10). OCT reduced the GH induced increase in serum IGF-I levels (P<0.05, ANOVA). Mean integrated levels (microg/l) were 359.1+/-49.6 (GH), and 301.6+/-58.9 (GH+OCT). OCT did not significantly reduce serum IGFBP-3 levels (microg/l) [3460+/-270 (GH), and 3112+/-435 (GH+/-OCT);P =0.14]. Serum levels of free IGF-I (P =0.39), IGF-II (P =0.54), and of the acid-labile subunit (ALS) of the ternary complex (P =0.50) were similar during GH+/-OCT as compared with GH alone. After 1 week off GH treatment, significantly lower levels of IGF-I, IGF-II, IGFBP-3, and ALS were recorded (P<0.001). Serum IGFBP-1 levels were significantly higher after GH+OCT than after GH alone (P<0.0001), and levels were even higher without GH. Serum insulin levels (pmol/l) were significantly higher after GH alone as compared with no GH (P<0.05, ANOVA), whereas OCT partly suppressed the insulinotropic effect of GH (P<0. 05) [mean: 114.5+/-33.0 (GH), 91.3+/-29.6 (GH+OCT), 65.9+/-22.5 (no GH)]. This was also reflected in higher blood glucose levels during GH+OCT. Finally, GH+OCT reduced glucagon levels significantly as compared with GH alone (P =0.02). In conclusion, 7 days' administration of OCT to GH-treated GHD patients slightly attenuated serum IGF-I generation, and tended to decrease levels of the other components of the 150 kDa ternary complex. Whether these effects are mediated directly by OCT or indirectly via the accompanying changes in insulin levels remains to be investigated.

Decreased acid-labile subunit (ALS) levels by endotoxin in vivo and by interleukin-1beta in vitro

The production by the liver of the three subunits of the growth hormone (GH)-dependent 150 kDa complex (IGF-I, IGF-binding protein-3 and acid-labile subunit or ALS) is primarily under the control of GH. Recent data have shown that, besides GH, endotoxin (LPS) and cytokines may regulate the liver IGF-I gene. To investigate the potential regulation of ALS by LPS, we measured serum ALS by immunoblot, 5 and 10 h after IP injection of LPS (250 or 750 microg/100 g BW vs saline), in 4-week-old female Wistar rats (four per group). Ten hours after injection, serum ALS levels were reduced by 57% (delta%) with the lower dose (P<0.05) and by 81% with the higher dose (P<0.01) by comparison with saline-treated rats. The decrease in ALS levels in response to LPS was not prevented by exogenous GH. To investigate the role of interleukin (IL)-1beta in the regulation of ALS, primary cultured rat hepatocytes were exposed to increasing concentrations of IL-1beta. Cell exposure to IL-1beta markedly decreased both basal and GH-stimulated ALS levels (-70%; P<0.01) in a dose-dependent fashion, with the half-maximal inhibitory effect at concentrations of 0.1 ng/ml. Our results show that endotoxin induces a rapid decline in circulating ALS that is potentially mediated through IL-1beta. By limiting the formation of the 150 kDa complex, this reduction in circulating ALS might contribute to the rapid decline in serum IGF-I observed in sepsis.