Serum concentrations of insulin-like growth factor 1 in colonic neoplasia

Post-diagnosis physical activity and sedentary behaviour and colorectal cancer prognosis: A Global Cancer Update Programme (CUP Global) systematic literature review and meta-analysis

Low physical activity and high sedentary behaviour have been clearly linked with colorectal cancer development, yet data on their potential role in colorectal cancer survival is limited. Better characterisation of these relationships is needed for the development of post-diagnosis physical activity and sedentary behaviour guidance for colorectal cancer survivors. We searched PubMed and Embase through 28 February 2022 for studies assessing post-diagnosis physical activity, and/or sedentary behaviour in relation to all-cause and cause-specific mortality and recurrence after colorectal cancer diagnosis. Total and recreational physical activity were assessed overall and by frequency, duration, intensity, and volume using categorical, linear, and non-linear dose-response random-effects meta-analyses. The Global Cancer Update Programme (CUP Global) independent Expert Committee on Cancer Survivorship and Expert Panel interpreted and graded the likelihood of causality. We identified 16 observational studies on 82,220 non-overlapping patients from six countries. Physical activity was consistently inversely associated with colorectal cancer morbidity and mortality outcomes, with 13%-60% estimated reductions in risk. Sedentary behaviour was positively associated with all-cause mortality. The evidence had methodological limitations including potential confounding, selection bias and reverse causation, coupled with a limited number of studies for most associations. The CUP Global Expert panel concluded limited-suggestive evidence for recreational physical activity with all-cause mortality and cancer recurrence. Total physical activity and its specific domains and dimensions, and sedentary behaviour were all graded as limited-no conclusion for all outcomes. Future research should focus on randomised trials, while observational studies should obtain objective and repeated physical activity measures and better adjustment for confounders.

The insulin-like growth factor axis: A biological mechanism linking physical activity to colorectal cancer survival

Physical activity (PA) is related to colorectal cancer (CRC) mortality, with approximately 15% of CRC deaths worldwide attributable to physical inactivity. Moreover, higher levels of PA in CRC survivors have been associated with a reduced risk of the disease recurring. Despite the recognised nexus between PA and the risk of CRC, the physiological mechanisms underlying the inverse relationship between PA and mortality following CRC diagnosis are less apparent, with evidence primarily drawn from epidemiological studies. The insulin-like growth factor (IGF) axis plays a central role in cellular growth, proliferation regulation, differentiation and apoptosis. Specifically, high levels of insulin-like growth factor 1 (IGF-1) have been consistently linked to the severity of CRC tumours. Further, insulin-like growth factor binding protein 3 (IGFBP-3) regulates the bioavailability of IGF-I and therefore plays a central role in CRC prognosis. Decreasing levels of IGF-1 and increasing levels of IGFBP-3 may thus be a plausible mechanism underlying the inverse association between PA and CRC survival.

Relationships between insulin-like growth factor i and selected clinico-morphological parameters in colorectal cancer patients

Insulin Like Growth Factor (IGF I) as the one of the strongest growth factors which can affect cancers development including colorectal cancer. IGF I induces processes of the cells growth and division. It regulates cells cycle and inhibits apoptosis. There is limited data about correlation between IGF I and staging of the tumor. The aim of the study was estimation of the clinical usefulness of IGF I concentration in the serum of the patients with colorectal cancer.

MATERIAL AND METHODS

We have examined 125 individuals with colorectal cancer. The age range was 36 to 92 years. They have been operated in the 2nd Departament of The Gastrointestinal Surgery of the Medical University in Białystok. Serum concentration of the IGF I have been estimated using immunoassay ELISA before and after operation. Correlation between serum level of IGF I and clinicopathologic features: age, gender, localisation of the primary tumor, TNM stage of tumor, histological type and histological grade (G) of the cancer have been estimated.

RESULTS

Our study revealed statistically significant increased serum concentration of IGF I in patients with locally advanced colorectal cancer (pT3 and pT4) comparing to less advanced (pT2) The investigations showed higher serum concentration of IGF I in patients with poorly differentiated cancers (G3) than in moderately differentiated. Similarly higher serum concentration of IGF I were found in male, in patients older than 60 years and in mucigenous colorectal cancers.

CONCLUSIONS

Our results indicated that IGF I can be one of the factors of the prognosis in colorectal cancer development.

Role of insulin-like growth factor-1 in colon cancerogenesis: a case-control study

BACKGROUND

Our aim was to establish whether individuals who developed colon cancer have elevated blood levels of insulin-like growth factor-1 (IGF-1).

METHODS

This was a case/control study in which 52 patients with colon cancer and a corresponding control group were investigated. Data on age, weight, height, and sex of subjects were recorded and levels of IGF-1 and growth hormone, as well as insulin and C-peptide levels, were measured in the morning before eating, 90 min after breakfast and again 90 min after lunch.

RESULTS

We found significantly higher levels of IGF-1 in blood of colon cancer patients compared to the control group. No differences in the levels of growth hormone, insulin and C-peptide in blood were found between colon cancer patients and the control group. It was found that the increase of IGF-1 level was followed by a 3.15-fold increased risk for developing colon cancer. There were no differences in the levels of IGF-1 in blood in all three measurements in the group of colon cancer patients, whereas differences were found in the control group. We found differences in the levels of insulin and C-peptide in blood in all three measurements in both groups of patients. No differences were found in the levels of growth hormone in blood in all three measurements in both groups of patients.

CONCLUSIONS

The results of this study suggest a positive correlation between the increased levels of IGF-1 and colon cancer and are thus consistent with the hypothesis that the level of IGF-1 plays an important role in the development of colon cancer.

The growth hormone-insulin-like growth factor-I axis and colorectal cancer

The growth hormone (GH)-insulin-like growth factor (IGF)-I axis is an important modulator of growth and development, but in addition to their classical role as endocrine hormones, its components also regulate a wide range of biological functions through paracrine and autocrine mechanisms. Their potent mitogenic and anti-apoptotic effects play a critical role in the regulation of rapidly renewing epithelial cell populations such as those found in the colon. Recent evidence suggests an association between inappropriate regulation of the GH-IGF-I axis and the development of colorectal cancer. However, the molecular mechanisms and signalling pathways responsible are only beginning to be unravelled, as are the relative contributions of the endocrine and autocrine or paracrine effects.

The effects of insulin-like growth factors on tumorigenesis and neoplastic growth

Several decades of basic and clinical research have demonstrated that there is an association between the insulin-like growth factors (IGFs) and neoplasia. We begin with a brief discussion of the function and regulation of expression of the IGFs, their receptors and the IGF-binding proteins (IGFBPs). A number of investigational interventional strategies targeting the GH or IGFs are then reviewed. Finally, we have assembled the available scientific knowledge about this relationship for each of the major tumor types. The tumors have been grouped together by organ system and for each of the major tumors, various key elements of the relationship between IGFs and tumor growth are discussed. Specifically these include the presence or absence of autocrine IGF-I and IGF-II production; presence or absence of IGF-I and IGF-II receptor expression; the expression and functions of the IGFBPs; in vitro and in vivo experiments involving therapeutic interventions; and available results from clinical trials evaluating the effect of GH/IGF axis down-regulation in various malignancies.