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Isolation and partial characterization of IGF-like peptides from Cohn fraction IV of human plasma

J. L. Van den Brande, C. M. Hoogerbrugge, K. Beyreuther, P. Roepstorff, J. Jansen, and S. C. van Buul-Offers

Abstract.

IGFs were extracted from Cohn fraction IV of human plasma using ultrafiltration of acidified paste as the initial step. Further purification, including HPLC as the final steps, yielded seven IGF-like peptides: two with acidic pI (A1, A2), two with neutral pI (N1, N2), and three in the basic region (B1, B2 and B3). B1 was identified as IGF-I and N1 as IGF-II. The other peptides were further characterized with respect to their molecular weight and by N-terminal amino-acid sequencing. B2 and B3 are IGF-I-like, Al and A2 and N2 are IGF-II-like. Two of the peptides (A2 and B3) appear to be two-chain forms of IGF-II and IGF-I, respectively, as shown by structural analysis and polyacrylamide gel electrophoresis. One peptide (Al) appears to be a new variant of an IGF-II derivative with a substitution of Ser by Cys in position 29. Further analysis involved reactivity in radioreceptor assays for IGF-I and IGF-II. N2, Al and A2 are IGF-II-like, whereas B2 and B3 are IGF-I-like, though there are important differences with the main IGFs. Similar results were obtained in IGF-I and IGF-II C-peptide radioimmunoassays. The physiological significance of these peptides is unknown. They offer interesting perspectives for structure-function analysis.

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Pheochromocytomas detected by biochemical screening in predisposed subjects are associated with lower prevalence of clinical and biochemical manifestations and smaller tumors than pheochromocytomas detected by signs and symptoms

N van Duinen, D Steenvoorden, B A Bonsing, J Vuyk, A H J T Vriends, J C Jansen, J A Romijn, and E P M Corssmit

Context

Sporadic pheochromocytomas are detected by clinical signs and symptoms, whereas pheochromocytomas in patients with a known hereditary predisposition for these tumors are detected by repetitive screening for catecholamine excess.

Objective

To document the clinical, biochemical, and pathological differences between patients with sporadic pheochromocytomas, detected by signs and symptoms and patients with pheochromocytomas, detected by biochemical screening in established hereditary syndromes.

Design

Retrospective follow-up study.

Patients and methods

We included 60 consecutive patients diagnosed with pheochromocytoma (pheochromocytomas detected by signs and symptoms: n=28 and pheochromocytomas detected by screening: n=32) in our center.

Results

Patients with pheochromocytomas detected by screening presented with less complaints of diaphoresis (P<0.01), palpitations (P=0.01), paleness (P=0.01), nausea (P<0.01), and vomiting (P=0.01) compared with patients with symptomatic pheochromocytomas. Patients with pheochromocytomas detected by screening tended to be younger at the time of diagnosis (41±2 vs 47±3 years, P=0.07). In addition, patients with pheochromocytomas detected by screening had significantly lower rates of 24-h urinary catecholamine excretion, and considerably smaller tumors (3.7±0.5 vs 7.3±0.7 cm, P<0.01).

Conclusions

Pheochromocytomas detected by screening of patients with a hereditary predisposition have a much lower prevalence of signs and symptoms, lower catecholamine excess, and smaller tumors, compared with sporadic pheochromocytomas, detected by signs and symptoms. These data support the benefits of screening for pheochromocytomas in patients with hereditary syndromes predisposing for these tumors.

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Quality of life is decreased in patients with paragangliomas

L T van Hulsteijn, A Louisse, B Havekes, A A Kaptein, J C Jansen, F J Hes, J W A Smit, and E P M Corssmit

Context

Germline mutations in succinate dehydrogenase (SDH) genes predispose carriers for developing paragangliomas, and studies on their quality of life (QoL) are scarce.

Objectives

The objectives of this study were to assess QoL in patients with paragangliomas (PGL), to evaluate long-term QoL, and to explore potential differences in QoL between SDH mutation carriers and paraganglioma patients without an SDH mutation.

Design

Cross-sectional, case–control study.

Setting

Tertiary referral center.

Subjects

One hundred and seventy four paraganglioma patients were included: 25 SDHB, two SDHC, and 122 SDHD mutation carriers and 25 patients without an SDH mutation. They provided 100 peers as control persons. Furthermore, patients were compared with age-adjusted reference populations.

Main outcome measures

QoL was assessed using three validated health-related QoL questionnaires: the Hospital Anxiety and Depression Scale, the Multidimensional Fatigue Index 20, and the Short Form 36.

Results

Patients reported a significantly impaired QoL compared with their own controls, mainly on fatigue and physical condition subscales. Compared with age-adjusted literature values, patients had significantly impaired scores on physical, psychological, and social subscales. A decreased QoL was mainly related to paraganglioma-associated complaints.

There was no difference in QoL between the various SDH mutation carriers or paraganglioma patients without an SDH mutation. QoL in asymptomatic mutation carriers, i.e. without manifest disease, did not differ from QoL of the general population. Long-term results in 41 patients showed no alteration in QoL besides a reduced level of activity.

Conclusion

QoL is decreased in paraganglioma patients but stable when measured over time.

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Reduced quality of life in patients with head-and-neck paragangliomas

B Havekes, A A van der Klaauw, H C Hoftijzer, J C Jansen, A G L van der Mey, A H J T Vriends, J W A Smit, J A Romijn, and E P M Corssmit

Objective

The objective of this study was to assess the quality of life (QoL) in patients with head-and-neck paragangliomas (‘glomus tumors’).

Design

We conducted a case–control study.

Methods

We assessed QoL in 82 patients with head-and-neck paragangliomas using four validated health-related questionnaires: Hospital Anxiety and Depression Scale, Multidimensional Fatigue Index (MFI-20), Short Form-36 (SF-36), and Nottingham Health Profile (NHP). Patient outcomes were compared with controls provided by the patients and with a large age- and sex-adjusted control group.

Results

The QoL scores in the paraganglioma patients were significantly reduced in 12 out of the 21 subscales compared with own controls, and in 18 out of the 21 subscales compared with age- and sex-adjusted values derived from the previous studies. In the MFI-20 questionnaire, patients reported more general fatigue, physical fatigue, mental fatigue, and a reduction in activity and motivation. The scores in the NHP showed a difference in energy, emotional reaction, and social isolation. General health perception, pain, and physical functioning were reported to be worse in the paraganglioma patients on the SF-36 scale. Although anxiety and depression did not reveal any significant differences between patients and their own controls, an increased score on both anxiety and depression was seen when compared with the extended control group. Especially, dysphonia contributes to a reduced QoL.

Conclusion

QoL is considerably reduced in patients with head-and-neck paragangliomas.

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Increased prevalence of catecholamine excess and phaeochromocytomas in a well-defined Dutch population with SDHD-linked head and neck paragangliomas

W H van Houtum, E P M Corssmit, P B Douwes Dekker, J C Jansen, A G L van der Mey, A H J T Bröcker-Vriends, P E M Taschner, M Losekoot, M Frölich, M P M Stokkel, C J Cornelisse, and J A Romijn

Objective: The aim of this study was to identify the prevalence of catecholamine excess and phaeochromocytomas in a well-defined population of people with hereditary head and neck paragangliomas.

Methods: We studied in a prospective follow-up protocol all consecutive patients referred to the Department of Endocrinology, Leiden University Medical Center, Leiden, The Netherlands with documented head and neck paragangliomas and either a positive family history for paragangliomas or a proven SDHD gene mutation. Initial analysis included medical history, physical examination and the measurement of excretion of catecholamines in two 24-h urine collections. In the case of documented catecholamine excess iodinated meta-iodobenzylguanidine (123I-MIBG) scintigraphy and magnetic resonance imaging were done.

Results: Between 1988 and 2003, 40 consecutive patients (20 male and 20 female) with documented head and neck paragangliomas were screened. Biochemical screening revealed urinary catechol-amine excess in 15 patients (37.5%). In nine of these 15 patients a lesion was found by 123I-MIBG scintigraphy. Exact localization by magnetic resonance imaging revealed phaeochromocytomas in seven of the 15 patients. One of the nine patients had an extra-adrenal paraganglioma. Histopathological examination in a subset of tumors displayed loss of heterozygosity of the wild-type SDHD allele in all cases.

Conclusions: The prevalence of catecholamine excess (37.5%) and phaeochromocytomas (20.0%) is high in patients with familial head and neck paragangliomas. Therefore, patients with hereditary head and neck paragangliomas require lifelong follow up by biochemical testing for catecholamine excess.