Acromegaly and Colorectal Neoplasm: An Update

The emerging role of miRNAs in pituitary adenomas: From molecular signatures to diagnostic potential

Pituitary adenomas (PAs) are an array of tumors originating from the pituitary gland. PAs are sorted as functional or nonfunctional according to their hormonal activity and classified according to size into microadenomas and macroadenomas. Still, the cellular events that trigger the transformations in pituitary neoplasms are not fully understood, and the current classification methods do not precisely predict clinical behavior. A rising number of researches have emphasized the role of miRNAs, that drawn more attention as oncogenic molecules or tumor suppressors. The etiopathological mechanisms of PAs include multiple molecular cascades that are influenced by different miRNAs. miRNAs control the cell cycle control, pro- or antiapoptotic processes, and tumor invasion and metastasis. miRNAs offer a novel perspective on tumor features and behaviors and might be valuable in prognostication and therapeutic plans. In pituitary adenomas, miRNAs showed a specific expression pattern depending on their size, cell origin, remission, and treatments. Screening miRNA expression patterns is promising to monitor and evaluate recurrence, as well as to investigate the efficacy of radiation and chemotherapy for PAs exhibiting aggressive behavior. Thus, the current review investigated the interplay of the miRNAs' pivotal role in offering new opportunities to translate these innovative epigenetic tools into healthcare applications.

Uterine fibroids in women diagnosed with acromegaly: a systematic review

The review discusses the relationship between acromegaly and uterine fibroids. It highlights variations in research methodologies and inconsistent findings, emphasizing the complex nature of fibroid development and the role of the somatotropic axis. Additionally, it addresses demographic factors and examines the potential impact of therapies on the risk and prevalence of uterine fibroids in individuals with acromegaly. We conducted an analysis of previously published literature that examined the repercussions of acromegaly on gynecological health in female cohorts, with specific attention directed towards elucidating the prevalence of uterine fibroids. We suggest that larger, more focused studies are needed to understand the specific impact of different treatments on the occurrence of gynecological issues in acromegaly patients. Additionally, our study emphasizes the importance of factors such as disease duration and treatment effectiveness. We hypothesize that a relationship between acromegaly and uterine fibroids may occur. However, it remains an area of ongoing research, with the need for larger, multi-center studies to draw more definitive conclusions.

Diabetes Risk Reduction Diet and Colorectal Cancer Risk

BACKGROUND

Diabetes has been associated with colorectal cancer. We evaluated whether adherence to a diabetes risk reduction diet (DRRD) can favorably influence the risk of colorectal cancer.

METHODS

Data came from a multicentric Italian case-control study including 1,953 histologically confirmed colorectal cancer cases and 4,154 hospital controls admitted for acute nonneoplastic diseases. Diet was assessed through a validated and reproducible food frequency questionnaire. The DRRD score was computed assigning higher values for higher consumption of cereal fiber, fruit, coffee, nuts and a higher polyunsaturated/saturated fats ratio and for lower glycemic index and lower consumption of red/processed meat and sweetened beverages and fruit juices. The ORs and the corresponding 95% confidence intervals (CI) of colorectal cancer according to the DRRD score were obtained using logistic regression models adjusting for total energy intake and other major confounders.

RESULTS

The DRRD was inversely related to colorectal cancer risk. The ORs of colorectal cancer were 0.77 (95% CI, 0.67-0.89) for the third versus first score tertile (Ptrend < 0.001) and 0.92 (95% CI, 0.87-0.96) for a 3-point increment in the score. Inverse associations were observed for colon and rectal cancers and were consistent in strata of sex, age, and other major covariates.

CONCLUSIONS

A higher adherence to a DRRD was inversely associated with colorectal cancer risk.

IMPACT

Given the high incidence and mortality rates of colorectal cancer, adherence to a DRRD can have relevant prevention and public health implications.

WIP1 is a novel specific target for growth hormone action

DNA damage repair (DDR) is mediated by phosphorylating effectors ATM kinase, CHK2, p53, and γH2AX. We showed earlier that GH suppresses DDR by suppressing pATM, resulting in DNA damage accumulation. Here, we show GH acting through GH receptor (GHR) inducing wild-type p53-inducible phosphatase 1 (WIP1), which dephosphorylated ATM and its effectors in normal human colon cells and three-dimensional human intestinal organoids. Mice bearing GH-secreting xenografts exhibited induced colon WIP1 with suppressed pATM and γH2AX. WIP1 was also induced in buffy coats derived from patients with elevated GH from somatotroph adenomas. In contrast, decreased colon WIP1 was observed in GHR-/- mice. WIP1 inhibition restored ATM phosphorylation and reversed GH-induced DNA damage. We elucidated a novel GH signaling pathway activating Src/AMPK to trigger HIPK2 nuclear-cytoplasmic relocation and suppressing WIP1 ubiquitination. Concordantly, blocking either AMPK or Src abolished GH-induced WIP1. We identify WIP1 as a specific target for GH-mediated epithelial DNA damage accumulation.

Incidence and risk factors of cancers in acromegaly: a Chinese single-center retrospective study

PURPOSE

To evaluate the incidence of malignancies in acromegaly and to identify risk factors for newly-diagnostic cancers, especially the excessive growth hormone (GH) and insulin-like growth factor-1 (IGF-1).

METHODS

A retrospective cohort including 1738 consecutive hospitalized patients with acromegaly in a single referral center between 2012 and 2020 (mean follow-up 4.3 years). A gender- and age-matched case-control study (280 patients from the cohort) was performed for risk factor analysis.

RESULTS

One hundred thirteen malignancies (67 diagnosed after acromegaly) were observed. The overall newly-diagnostic cancer risk of acromegaly was higher than the general population (standardized incidence ratio (SIR) 2.81; 95% CI 2.18-3.57). The risk of thyroid cancer (n = 33, SIR 21.42; 95% CI 13.74-30.08) and colorectal cancer (n = 8, SIR 3.17; 95% CI 1.37-6.25) was elevated. In the overall cohort, IGF-1 (ULN: 1.27 vs. 0.94, p = 0.057), GH (1.30 vs. 1.00 ng/ml, p = 0.12), and disease-controlled rate (34.9% vs. 45.9%, p = 0.203) at the last visit did not reach significance between patients with and without post-diagnostic cancer. In the case-control study, GH (1.80 vs. 0.90 ng/ml, p = 0.018) and IGF-1 (ULN: 1.27 vs. 0.91, p = 0.003) at the last visit were higher in patients with post-diagnostic cancers, with a lower disease-controlled rate. Elder age was a risk factor for cancer. Other metabolic comorbidities and the size of pituitary tumors were similar.

CONCLUSION

The risk of malignancies, especially thyroid cancer, was increased in patients with acromegaly in our center. More cancer screening should be considered when managing acromegaly, especially in patients with higher posttreatment GH and IGF-1.

Simultaneous rectal neuroendocrine tumors and pituitary adenoma: A case report and review of literature

BACKGROUND

Neuroendocrine tumors (NET) are rare heterogeneous tumors that arise from neuroendocrine cells throughout the body. Acromegaly, a rare and slowly progressive disorder, usually results from a growth hormone (GH)-secreting pituitary adenoma.

CASE SUMMARY

We herein describe a 38-year-old patient who was initially diagnosed with diabetes. During colonoscopy, two bulges were identified and subsequently removed through endoscopic submucosal dissection. Following the surgical intervention, the excised tissue samples were examined and confirmed to be grade 2 NET. 18F-ALF-NOTATATE positron emission tomography-computed tomography (PET/CT) and 68Ga-DOTANOC PET/CT revealed metastases in the peri-intestinal lymph nodes, prompting laparoscopic low anterior resection with total mesorectal excision. The patient later returned to the hospital because of hyperglycemia and was found to have facial changes, namely a larger nose, thicker lips, and mandibular prognathism. Laboratory tests and magnetic resonance imaging (MRI) suggested a GH-secreting pituitary adenoma. The pituitary adenoma shrunk after treatment with octreotide and was neuroendoscopically resected via a trans-sphenoidal approach. Whole-exome sequencing analysis revealed no genetic abnormalities. The patient recovered well with no evidence of recurrence during follow-up.

CONCLUSION

18F-ALF-NOTATE PET/CT and MRI with pathological analysis can effectively diagnose rare cases of pituitary adenomas complicated with rectal NET.

Treatment Patterns, Adherence, Persistence, and Health Care Resource Utilization in Acromegaly: A Real-World Analysis

Context

Treatment of acromegaly is multimodal for many patients, and medical treatments include somatostatin receptor ligands (SRLs), dopamine agonists (DAs), and growth hormone receptor antagonists (GHRAs). However, recent real-world evidence on treatment patterns for patients with acromegaly is limited.

Objective

This study evaluated medication usage, treatment changes, adherence, persistence, comorbidities, and health care resource utilization using deidentified data from MarketScan, a US claims database.

Methods

Eligible patients (n = 882) were those receiving monotherapy or combination therapy for ≥90 days without treatment gaps.

Results

Mean age at diagnosis was 48.6 years; 50.1% of patients were female. Over half (59.4%) had 1 line of treatment (LOT); 23.1% had 2 LOTs; 17.5% had at least 3 LOTs. Most patients (94.6%) initiated treatment with monotherapies. The most common first-line monotherapy treatments were cabergoline (DA, 36.8%), octreotide long-acting release (first-generation SRL, 29.5%), and lanreotide depot (first-generation SRL, 22.5%). Adherence for first-line treatments (proportion of days covered) was higher for first-generation SRLs (lanreotide depot: 0.8) compared with DAs (0.7). Treatment persistence (time between the first treatment record and a change in LOT/censoring) in LOT 1 was higher for GHRAs (24.8 months) and first-generation SRLs (20.0 months) compared with DAs (14.4 months). Female patients and those diagnosed at a younger age were more likely to have shorter treatment persistence. The most prevalent comorbidities were hyperlipidemia, essential hypertension, and sleep apnea.

Conclusion

Patients with more comorbidities had more health care visits during the first year after diagnosis, suggesting increased disease burden. Real-world evidence on treatment patterns provides insights into recommendations for individualized therapy.

Trends in incidence and mortality risk for acromegaly in Norway: a cohort study

PURPOSE

Recent data have shown a decreasing overall mortality in acromegaly over the last decades. However, cancer incidence and cancer-related mortality still appear to be increased. Our aim was to obtain updated epidemiological data from Norway in a clinically well-defined cohort with complete register-based follow-up.

METHODS

Patients diagnosed with acromegaly from South-Eastern Norway between 1999-2019 (n = 262) and age and sex matched population controls (1:100) were included (n = 26,200). Mortality and cancer data were obtained from the Norwegian Cause of Death and Cancer Registry. Mortality and cancer incidence were compared by Kaplan-Meier analyses and Cox regression; we report hazard ratios (HRs) with 95% confidence intervals (95% CI).

RESULTS

Median age at diagnosis was 48.0 years (interquartile range (IQR): 37.6-58.0). Mean annual acromegaly incidence rate was 4.7 (95% CI 4.2-5.3) cases/10⁶ person-years, and the point prevalence (2019) was 83 (95% CI 72.6-93.5) cases/10⁶ persons. Overall mortality was not increased in acromegaly, HR 0.8 (95% CI 0.5-1.4), cancer-specific and cardiovascular-specific mortality was also not increased (HR: 0.7 (95% CI 0.3-1.8) and 0.8 (95% CI: 0.3-2.5) respectively). The HR for all cancers was 1.45 (1.0-2.1; p = 0.052).

CONCLUSION

In this large cohort study, covering the period 1999-2019, patients were treated with individualized multimodal management. Mortality was not increased compared to the general population and comparable with recent registry studies from the Nordic countries and Europe. Overall cancer risk was slightly, but not significantly increased in the patients.

Mechanisms of ageing: growth hormone, dietary restriction, and metformin

Tackling the mechanisms underlying ageing is desirable to help to extend the duration and improve the quality of life. Life extension has been achieved in animal models by suppressing the growth hormone-insulin-like growth factor 1 (IGF-1) axis and also via dietary restriction. Metformin has become the focus of increased interest as a possible anti-ageing drug. There is some overlap in the postulated mechanisms of how these three approaches could produce anti-ageing effects, with convergence on common downstream pathways. In this Review, we draw on evidence from both animal models and human studies to assess the effects of suppression of the growth hormone-IGF-1 axis, dietary restriction, and metformin on ageing.

miR-383-5p, miR-181a-5p, and miR-181b-5p as Predictors of Response to First-Generation Somatostatin Receptor Ligands in Acromegaly

Acromegaly is a chronic systemic disease caused in the vast majority of cases by growth hormone (GH)-secreting adenoma, with surgery being the first-line treatment. When a cure is not attained with surgery, first-generation somatostatin receptor ligands (fg-SRLs) are the most common medication prescribed. Predictors of response to fg-SRLs have been studied; however, they cannot fully predict the response to fg-SRL. MicroRNAs are small RNAs, the main role of which is messenger RNA (mRNA) post-transcriptional regulation. This study aimed to identify the microRNAs involved in resistance to treatment with fg-SRLs in acromegaly. Ten patients with acromegaly undergoing treatment with fg-SRLs were selected to undergo miRNA sequencing: five controlled and five uncontrolled with treatment. Bioinformatic analysis was performed to detect differentially expressed miRNAs. Then, the same 10 samples were used for validation by qPCR and an additional 22 samples were analyzed, totaling 32 samples. e We found 59 differentially expressed miRNAs in the first analysis. miR-181a-5p and miR-181b-5p were downregulated, and miR-383-5p was upregulated in the uncontrolled group. Receiver operating characteristic (ROC) curve analysis of miR-383-5p showed an NPV of 84.3% and a PPV of 84.5%. In summary, miR-181a-5p, miR-181b-5p, and miR-383-5p are biomarkers of response to fg-SRLs, and they can be used individually or included in prediction models as tools to guide clinical decisions.

Serum biomarkers of colonic polyps in patients with acromegaly: a meta-analysis and systematic review

PURPOSE

In the past few decades, acromegaly and colonic polyps have been associated with an increased risk of colorectal cancer. Previous studies highlighted the importance of serum biomarkers of colonic polyps in patients with acromegaly.

METHODS

We reviewed studies on serum biomarkers of colonic polyps in patients with acromegaly, published on PubMed, Embase, Cochrane Library, Medline, and Chinese databases from January 1, 1966, to May 8, 2022. Meta-analysis and systematic review were conducted using Stata MP 14.0.

RESULTS

Eight articles were included in this study. The mean (standard deviation) concentrations of serum biomarkers for acromegaly with and without colorectal polyps were extracted from these studies. Meta-analysis results showed that, compared to patients without colonic polyps, the levels of insulin-like growth factor-1 × upper limit of normal range (IGF-1 × ULN) and fasting insulin were significantly increased; while the levels of growth hormone (GH) were significantly decreased in patients with acromegaly and colonic polyps (IGF-1 × ULN: SMD 0.23; 95% CI 0.03-0.42, p < 0.05) (fasting insulin: SMD 0.95; 9 5% CI 0.11-1.8, p < 0.05) (GH: SMD - 0.25; 95% CI - 0.41 to - 0.08, p < 0.05). IGF-1 and FPG levels did not differ significantly (IGF-1: SMD -0.03; 95% CI - 0.22 to 0.17, p > 0.05) (FPG: SMD 0.14; 95% CI - 0.23 to 0.52, p > 0.05). The systematic review results suggest no significant differences in hemoglobin A1C, TSH, free thyroxine, FT4, T3, PRL, total cholesterol, HDL, LDL, fibrinogen, clathrate antigen, serum antigen 19-9, and α-fetoprotein levels, but serum Klotho levels.

CONCLUSION

We present the first meta-analysis and systematic review of serum biomarkers in patients with acromegaly or colonic polyps. The prevalence of colonic lesion polyps, is associated with higher IGF-1 × ULN levels, higher insulin levels in acromegaly. Further research is required to confirm GH and serum soluble Klotho levels as biomarkers of colonic polyps. When IGF-1 × ULN, fasting insulin levels change in patients with acromegaly, the occurrence of colonic polyps should be monitored. Early detection may reduce the possibility of developing malignant colon neoplasms.

MicroRNA in Acromegaly: Involvement in the Pathogenesis and in the Response to First-Generation Somatostatin Receptor Ligands

Acromegaly is a chronic and systemic disease due to excessive growth hormone and insulin-like growth factor type I caused, in the vast majority of cases, by a GH-secreting pituitary adenoma. About 40% of these tumors have somatic mutations in the stimulatory G protein alpha-subunit 1 gene. The pathogenesis of the remaining tumors, however, is still not fully comprehended. Surgery is the first-line therapy for these tumors, and first-generation somatostatin receptor ligands (fg-SRL) are the most prescribed medications in patients who are not cured by surgery. MicroRNAs are small, non-coding RNAs that control the translation of many mRNAs, and are involved in the post-transcriptional regulation of gene expression. Differentially expressed miRNAs can explain differences in the pathogenesis of acromegaly and tumor resistance. In this review, we focus on the most validated miRNAs, which are mainly involved in acromegaly’s tumorigenesis and fg-SRL resistance, as well as in circulating miRNAs in acromegaly.