Do insulin-like growth factor associated proteins qualify as a tumor marker? results of a prospective study in 163 cancer patients*

Abstract

ObjectiveInsulin-like growth factor (IGF)-1, -2 and Insulin like growth factor binding proteins (IGFBP) are involved in the proliferation and differentiation of cells. It has never been evaluated, if the IGF-system can serve as a tumor marker in neoplasms.MethodsIn our prospective study 163 patients with colorectal cancer (22), prostate cancer (21), head and neck tumors (17), lymphomas (20), lung cancer (34) and other entities (49) were analysed for their IGF and IGFBP serum levels at the beginning and the end of radiotherapy and compared to 13 healthy people. Subgroups of patients with local tumor disease versus metastatic disease, primary and recurrent therapy and curative versus palliative therapy were compared.ResultsThe serum levels of IGF-2 were significantly elevated in patients with prostate and colorectal cancer. However, sensitivity and specificity were only 70%. IGFBP-2 serum levels were elevated in patients with head and neck tumors. Again sensitivity and specificity were only 73%. A difference between local disease and metastatic disease could not be found. A difference between IGF serum levels before and after radiotherapy could not be detected.ConclusionThe IGF-system cannot serve as a new tumor marker. The detected differences are very small, sensitivity and specificity are too low. IGF measurement is not useful for the evaluation of the success of radiotherapy in malignancies.

Twelve Serum Proteins Progressively Increase With Disease Stage in Squamous Cell Cervical Cancer Patients

“…The insulin-like growth factor (IGF) axis and a family of 6 high-affinity IGF-binding proteins (IGFBPs) have an important role in the development and progression of many epithelial cancers. 25,26 Insulin-like growth factor binding protein 2 promotes IGF-IY and IGF-IIYinduced cell signaling, probably via prolonging IGF half-life, and hence cell exposure or by sequestering IGFs at the cell surface and increasing levels in the vicinity of cell receptors. 27 Similar studies with much smaller sample sizes 26 also found elevated IGFBP2 serum levels in patients with prostate, lung, colon cancer, head and neck tumors, and lymphoma.…”

Impact of targeting insulin-like growth factor signaling in head and neck cancers

“…This suggests that elevated IGFBP-3 contributes to increased proliferation in late stages of cancer development. Serum levels of IGFBP-2 have also been reported to be elevated in head and neck cancer patients when compared to healthy controls (33). Conversely, this same study reported no differences in serum levels of IGF-1, IGF-2 and IGFBP-3 between these two populations (33).…”

“…Serum levels of IGFBP-2 have also been reported to be elevated in head and neck cancer patients when compared to healthy controls (33). Conversely, this same study reported no differences in serum levels of IGF-1, IGF-2 and IGFBP-3 between these two populations (33). In oral cavity squamous cell carcinoma (OCSCC), elevated intratumoral expression of IGF-1-R was significantly higher in patients with grade II-III when compared to patients with grade I disease (34).…”

The insulin-like growth factor (IGF) axis as an anticancer target in prostate cancer

“…For example, a large prospective study did not observe any association of pre-diagnostic IGF1 or IGFBP3 with risk of developing PCa [111]. Similarly, Matuschek et al reported that serum IGF and IGFBPs are not useful tumor markers and are not suitable to evaluate the success of radiotherapy in PCa [104].…”

“…In general, data on the impact of IGFBPs in PCa are very conflicting [104][105][106][107]. For example, in 2012, Rowlands et al published results from the largest study to date investigating the association of circulating components of the IGF axis with PCa.…”