Factors Affecting Central Node Metastasis and Metastatic Lymph Node Ratio in Papillary Thyroid Cancer

OBJECTIVE

Despite the growing evidence that metastatic lymph node ratio (MLNR) is a valuable predictor for the prognosis of papillary thyroid carcinoma, it has not yet been fully determined which factors give the ratio predictive value independent of the number of metastatic lymph nodes (MLNs).

STUDY DESIGN

Retrospective cohort study.

SETTING

A comprehensive cancer center.

METHODS

Recurrence and clinicopathologic factors were analyzed in 2409 patients with papillary thyroid carcinoma who underwent total thyroidectomy and central node dissection.

RESULTS

Cutoff values of MLNs ≥2 and MLNR ≥28.2% increased the recurrence risk (hazard ratio [95% CI], 9.97 [4.73-21.0] and 11.4 [5.53-23.3], respectively). Younger age, male sex, multifocality, tumor size, lymphatic and vascular invasion, and gross extrathyroidal extension positively correlated with MLN and MLNR (all P < .05). Meanwhile, lymphocytic thyroiditis negatively correlated with MLNR in female patients (P < .001), by increasing total lymph node yields as compared with papillary thyroid carcinoma without lymphocytic thyroiditis. In multivariate analysis, younger age, tumor size, and lymphatic invasion remained significant in male and female patients for MLN and MLNR; lymphocytic thyroiditis was also significantly correlated with MLNR in female patients.

CONCLUSION

Our study demonstrates that MLN and MLNR are independently observed prognostic markers for tumor recurrence. However, lymphocytic thyroiditis in female patients seems to have lower MLNR by increasing total lymph node yields. In light of their association, a different cutoff for MLNR needs to be applied according to the presence or absence of underlying lymphocytic thyroiditis in the use of MLNR for predicting the recurrence.

LEVEL OF EVIDENCE

4.

Depletion of HNRNPA1 induces peroxisomal autophagy by regulating PEX1 expression

Peroxisomes play an essential role in cellular homeostasis by regulating lipid metabolism and the conversion of reactive oxygen species (ROS). Several peroxisomal proteins, known as peroxins (PEXs), control peroxisome biogenesis and degradation. Various mutations in the PEX genes are genetic causes for the development of inheritable peroxisomal-biogenesis disorders, such as Zellweger syndrome. Among the peroxins, PEX1 defects are the most common mutations in Zellweger syndrome. PEX1 is an AAA-ATPase that regulates the recycling of PEX5, which is essential for importing peroxisome matrix proteins. However, the post-transcriptional regulation of PEX1 is largely unknown. Here, we showed that heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) controls PEX1 expression. In addition, we found that depletion of HNRNPA1 induces autophagic degradation of peroxisome, which is blocked in ATG5-knockout cells. In addition, depletion of HNRNPA1 increased peroxisomal ROS levels. Inhibition of the generation of peroxisomal ROS by treatment with NAC significantly suppressed pexophagy in HNRNPA1-deficient cells. Taken together, our results suggest that depletion of HNRNPA1 increases peroxisomal ROS and pexophagy by downregulating PEX1 expression.

Best Achievements in Clinical Thyroidology in 2020

This review highlights the most interesting research in thyroidology conducted in 2020. The publications of interest discussed below dealt with the following topics: thyroid dysfunction, risk of thyroid cancer, molecular diagnostics and new therapeutics for thyroid cancer, and thyroid disease in the coronavirus disease 2019 pandemic era.

Mitochondrial Glutamine Metabolism Determines Senescence Induction After Chemotherapy

BACKGROUND/AIM

Cellular senescence is an important tumor-suppressive mechanism that arrests the cell cycle of damaged cells after diverse stresses. This study aimed to elucidate the role of mitochondrial glutamine (Gln) metabolism in senescence cell-fate decision after DNA damage.

MATERIALS AND METHODS

β-galactosidase staining was used to determine senescence induction. The mechanistic target of rapamycin (mTOR) activity and p21 expression were examined by western blot. Cell proliferation and clonogenic growth were evaluated.

RESULTS

Inhibition of mitochondrial Gln metabolism suppressed DNA damage-induced senescence, whereas increased Gln anaplerosis resulted in a profound induction of senescence. Mechanistically, Gln anaplerosis mediated senescence induction by activating mTOR signaling upon DNA damage. Importantly, enhancing Gln anaplerosis could reduce the emergence of proliferative subpopulations of cancer cells after exposure to non-lethal doses of chemotherapeutic agents.

CONCLUSION

Mitochondrial Gln metabolism is an important regulator of DNA damage-induced senescence, which may be used for developing effective therapeutic approaches.

Association among Body Mass Index, Genetic Variants of FTO, and Thyroid Cancer Risk: A Hospital-Based Case-Control Study of the Cancer Screenee Cohort in Korea

Purpose

Obesity has been determined to be associated with fat mass and obesity-associated (FTO) gene and thyroid cancer risk. However, the effect of combined interactions between obesity and the FTO gene on thyroid cancer needs further investigation. This study aimed to examine whether interactions between body mass index (BMI) and the FTO gene are associated with an increased risk of thyroid cancer.

Materials and Methods

A total of 705 thyroid cancer cases and 705 sex- and age-matched normal controls were selected from the Cancer Screenee Cohort in National Cancer Center, Korea. A conditional logistic regression model was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for the measure of associations and the combined effect of BMI and FTO gene on thyroid cancer.

Results

BMI was associated with an increased risk of thyroid cancer in subclasses of overweight (23–24.9 kg/m²; adjusted OR, 1.50; 95% CI, 1.12 to 2.00) and obese (≥ 25 kg/m²) (adjusted OR, 1.62; 95% CI, 1.23 to 2.14). There were positive associations between the FTO genetic variants rs8047395 and rs8044769 and an increased risk of thyroid cancer. Additionally, the combination of BMI subclasses and FTO gene variants was significantly associated with thyroid cancer risk in the codominant (rs17817288), dominant (rs9937053, rs12149832, rs1861867, and rs7195539), and recessive (rs17817288 and rs8044769) models.

Conclusion

Findings from this study identified the effects of BMI on thyroid cancer risk among individuals carrying rs17817288, rs9937053, rs12149832, rs1861867, rs7195539, and rs8044769, whereas the effects of BMI may be modified according to individual characteristics of other FTO variants.

Randomized phase II study of platinum-based chemotherapy plus controlled diet with or without metformin in patients with advanced non-small cell lung cancer

OBJECTIVES

Accumulating evidence indicates anti-diabetic drug metformin has anti-cancer effect by controlling cancer metabolism. We evaluated whether addition of metformin to chemotherapy improved survival of lung cancer patients.

MATERIALS AND METHODS

This randomized phase II study enrolled 164 patients with chemo-native, EGFR-ALK wild-type, stage IIIB/IV non-small-cell lung cancer (NSCLC). Patients were randomized to receive chemotherapy either with metformin (1000 mg twice daily) or alone every 3 weeks for six cycles. The patients received gemcitabine (1000 mg/m²) on days 1 and 8 and carboplatin (5 area under the curve) on day 1. Exploratory studies included serum metabolic panels, positron-emission tomography (PET) imaging, and genetic mutation tests for metabolism-related genes.

RESULTS

Metformin group showed no significant difference in the risk of progression and death compared to control group (progression: hazard ratio [HR] = 1.01 [95% confidence interval (CI) = 0.72 - 1.42], P = 0.935; death: HR = 0.95 [95% CI = 0.67-1.34], P = 0.757). Squamous cell carcinoma (SqCC) had significantly higher fluorodeoxyglucose (FDG) uptake on baseline PET image than non-SqCC NSCLC (P = 0.004). In the SqCC with high FDG uptake, the addition of metformin significantly decreased the risk of progression and death (progression: HR = 0.31 [95% CI = 0.12-0.78], P = 0.013; death: HR = 0.42 [95% CI = 0.18-0.94], P = 0.035). The HDL-cholesterol level was significantly increased after the treatment in metformin group compared to control group (P = 0.011). The metformin group showed no survival benefit in the patients with hyperinsulinemia or patients whose insulin level was decreased after treatment.

CONCLUSIONS

Addition of metformin to chemotherapy provided no survival benefit in unselected NSCLC patients. However, it significantly improved the survival of the selected patients with SqCC showing high FDG uptake. It suggests metformin shows the synergistic anti-tumor effect in the tumor which are highly dependent on glucose metabolism.

Long Work Hours Are Associated with Hypothyroidism: A Cross-Sectional Study with Population-Representative Data

Background: Studies have highlighted the adverse effects of long work hours on workers' health; however, the association of long work hours with thyroid function has not been studied. This study aimed at assessing long work hours as a risk factor for thyroid dysfunction. Methods: This cross-sectional study was based on data obtained from the Korea National Health and Nutrition Examination Survey conducted from 2013 to 2015. A total of 2160 adults who worked 36-83 hours per week were included. Thyroid function was defined based on the population thyroid-stimulating hormone reference ranges, after excluding individuals with positive results for thyroid peroxidase antibody. The association between work hours and thyroid function was confirmed via multinomial logistic regression. Results: Hypothyroidism was more prevalent among those with longer work hours (3.5% vs. 1.4% for 53-83 and 36-42 work hours per week, respectively). Individuals who worked longer hours had an increased odds for hypothyroidism (odds ratio 1.46, confidence interval 1.12 - 1.90, per 10-hour increase in work hours per week), after adjustment for age, sex, body mass index, urine iodine concentration, smoking status, work schedule, and socioeconomic status. The association between work hours and hypothyroidism was consistent in various subgroups stratified by sex or socioeconomic status. Conclusions: To our knowledge, this study is the first to show that long work hours are associated with hypothyroidism. Further large longitudinal studies are needed to clarify causality.

A Phase II Multi-Center, Non-Randomized, Parallel Group, Non-Inferiority Study to Compare the Efficacy of No Radioactive Iodine Remnant Ablation to Remnant Ablation Treatment in Low- to Intermediate-Risk of Papillary Thyroid Cancer: The MOREthyroid Trial Protocol

BACKGROUND

Radioactive iodine (RAI) remnant ablation is recommended in patients with papillary thyroid cancer (PTC) and extrathyroidal extension or central lymph node metastasis. However, there exists little evidence about the necessity of remnant ablation in PTC patients with low- to intermediate-risk, those have been increasing in recent decades.

METHODS

This multicenter, prospective, non-randomized, parallel group clinical trial will enroll 310 eligible patients with low- to intermediate-risk of thyroid cancer. Inclusion criteria are patients who recently underwent total thyroidectomy for PTC with 3 or less tumors of size 1≤ to ≤2 cm with no microscopic extension and N0/x, or size ≤2 cm with microscopic extension and/or N1a (number of lymph node ≤3, size of tumor foci ≤0.2 cm, and lymph node ratio &lt;0.4). Patients choose to undergo RAI ablation (131I, dose 1.1 GBq) or diagnostic whole-body scan (DxWBS) (131I or 123I, dose 0.074 to 0.222 GBq), followed by subsequent measurement of stimulated thyroglobulin (sTg) within 1 year. Survey for quality of life (QOL) will be performed at baseline and at 1 year after follow-up. The total enrollment period is 5 years, and patients will be followed up for 1 year. The primary endpoint is the non-inferiority of surgery alone to surgery with ablation in terms of biochemical remission (BCR) rate (sTg ≤2 ng/mL) without evidence of structural recurrence. The secondary endpoint was the difference of QOL.

CONCLUSION

This study will evaluate whether surgery alone achieves similar BCR and improved QOL compared to RAI ablation in patients with low- to intermediate-risk PTC within 1 year.

Aspirin Use Is Not Associated with Lower Thyroid Cancer Risk: A Nationwide Nested Case-Control Study

Background: While aspirin use is known to be associated with reduced incidence of various cancer types, it is unclear whether this benefit extends to thyroid cancer. We aimed to evaluate the association between aspirin use and thyroid cancer development. Methods: This nested case-control study used nationwide data from the Korean National Health Insurance Service-National Sample Cohort 2002-2015. In total, 4547 individuals with newly developed thyroid cancer were matched with 13,641 controls based on age, sex, and follow-up period. Odds ratios (ORs) and 95% confidence intervals (CIs) for thyroid cancer development according to aspirin use were analyzed using a multivariable conditional logistic regression model. Results: The number of days for which patients with thyroid cancer used aspirin (the proportions of no use, <30 days/year, 30-90 days/year, and ≥90 days/year were 93.03%, 6.51%, 0.31%, and 0.15%, respectively) was comparable with that of the controls (p = 0.371, chi-squared test). The risk of thyroid cancer development was not associated with the duration of aspirin use (ORs [CI] for aspirin use <30 days/year, 30-90 days/year, and ≥90 days/year were 1.11 [0.96-1.28], 1.01 [0.54-1.88], and 1.23 [0.50-3.06], respectively, compared with no use) after adjusting for body mass index, smoking status, hypertension, Charlson comorbidity index, and number of outpatient visits per year. In addition, subgroup analyses stratified by age, sex, and follow-up duration did not reveal any significant association between aspirin use and thyroid cancer. Conclusions: Our findings suggest that even extended aspirin use may not impact the prevention or onset of thyroid cancer.

OR28-06 Assessment of Long Term Quality of Life According to Treatment Options in Low Risk Papillary Thyroid Microcarcinoma Patients - Active Surveillance or Immediate Surgery, (A Follow up Interim Analysis of Maestro)

Background: The Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) started in June 2016. As a follow-up study of comparing the quality of life (QoL) of the active surveillance (AS) and immediate surgery (OP) groups at 8 months (9.3±4.8 and 7.1±4.2 months, respectively), here we aimed to compare the QoL between the AS and OP groups after 18 months (22.8±4.0 and 22.3±4.3 months, respectively) of follow-up.

Methods: QoL of 108 participants who chose AS, 101 who underwent OP, twelve who changed from AS to OP was evaluated using a thyroid‐specific QoL questionnaire at diagnosis and during follow‐up (median 23 months).

Results: The mean ages of the participants in the AS and OP groups were 47.7±11.0 and 45.1±10.0 years (p=0.075), respectively. At baseline, better physical (8.2±1.4 vs. 7.6±1.8, p=0.032), psychological (7.4±1.2 vs. 6.7±1.6, p=0.010), and total health (7.4±1.0 vs. 6.7±1.3, p=0.005) were observed in the AS group than in the OP group. After a mean follow up of 22.7±4.2 months, better physical (8.1±1.5 vs. 7.4±1.7, p=0.008), psychological (7.7±1.3 vs. 7.0±1.5, p=0.002), and total health (7.5±1.2 vs. 6.8±1.3, p=0.001) were observed in the AS group than in the OP group, whereas spiritual health was comparable between the two groups: compared with the AS group, the OP group experienced more alterations in appetite, sleep, menstrual cycle, voice, motor skill, weight, appearance, cold or heat tolerance, and body swelling. Furthermore, better QOL scores were observed in the AS group in self-concept, personal relationships, sexual life, work motivation, productivity and quality of work, feeling of isolation, driving, doing household chores, preparing meals and doing leisure activities after long term follow up.

Conclusion: Patients who underwent AS had better QOL even after long term follow up. Low risk papillary thyroid microcarcinomas do not influence survival, however surgery related deterioration of QOL lasted long and did not improve even in late post-operative stages when patients were fully recovered from surgery.

Keywords: Quality of life; papillary thyroid microcarcinoma; active surveillance; immediate surgery

SUN-417 Long Working Hours Are Associated with Hypothyroidism: A Cross-Sectional Study with Population-Representative Data

Background: Studies have highlighted the adverse effects of long working hours on workers’ health; however, the association of long working hours with thyroid function has not been studied. This study aimed to assess long working hours as a risk factor for thyroid dysfunction.

Methods: This cross-sectional study was based on data obtained from the Korea National Health and Nutrition Examination Survey conducted from 2013 to 2015. A total of 2,160 adults who worked 36–83 hours per week were included. Thyroid function was defined based on the population thyroid-stimulating hormone reference ranges, after excluding individuals with positive results for thyroid peroxidase antibody. The association between working hours and thyroid function was confirmed via multinomial logistic regression.

Results: Hypothyroidism was more prevalent among those with longer working hours (3·5% vs. 1·4% for 53–83 and 36–42 working hours per week, respectively). Individuals who worked longer hours had an increased odds for hypothyroidism (odds ratio 1·46, 95% confidence interval 1·12−1·90, per 10 hour increase in working hours per week), after adjustment for age, sex, body mass index, urine iodine concentration, smoking status, shift work, and socioeconomic characteristics such as occupation, income level, and educational attainment. The association between working hours and hypothyroidism was consistent in various subgroups stratified by sex or socioeconomic characteristics.

Conclusions: To our knowledge, this study is the first to show that long working hours are associated with hypothyroidism. Our findings suggest that appropriate monitoring and treatment of hypothyroidism are necessary among individuals who work long hours.

RNA binding protein HuD contributes to β-cell dysfunction by impairing mitochondria dynamics

Imbalanced mitochondrial dynamics in pancreatic β-cells contributes to β-cell dysfunction in diabetes; however, the molecular mechanisms underlying mitochondrial dynamics in the pathology of diabetes are not fully elucidated. We previously reported the reduction of RNA binding protein HuD in pancreatic β-cells of diabetes. Herein, we demonstrate that HuD plays a novel role in the regulation of mitochondrial dynamics by promoting mitochondrial fusion. We show enhanced mitochondrial fragmentation in the pancreas of db/db mice and HuD KO mice. Downregulation of HuD increases the number of cells with fragmented mitochondria and reduces the mitochondrial activity determined by mitochondrial membrane potential and ATP production in mouse insulinoma βTC6 cells. HuD binds to 3'-untraslated region of mitofusin 2 (Mfn2) mRNA and positively regulates its expression. Ectopic expression of Mfn2 in βTC6 cells stably expressing short hairpin RNA against HuD (shHuD) restores HuD-mediated mitochondrial dysfunction. Taken together, our results suggest that HuD regulates mitochondrial dynamics by regulating Mfn2 level and its reduced expression leads to mitochondrial dysfunction in pancreatic β-cells.

Spatially and Temporally Explicit Life Cycle Environmental Impacts of Soybean Production in the U.S. Midwest

Understanding spatially and temporally explicit life cycle environmental impacts is critical for designing sustainable supply chains for biofuel and animal sectors. However, annual life cycle environmental impacts of crop production at county scale across mutiple years are lacking. To address this knowledge gap, this study used a combination of Environmental Policy Integrated Climate and process-based life cycle assessment models to quantify life cycle global warming (GWP), eutrophication (EU) and acidification (AD) impacts of soybean production in nearly 1000 Midwest counties yr-1 over 9 years. Sequentially, a machine learning approach was applied to identify the top influential factors among soil, climate, and farming practices, which drive the spatial and temporal heterogeneity of life cycle environmental impacts. The results indicated that significant variations existed in life cycle GWP, EU, and AD among counties and across years. Life cycle GWP impacts ranged from -11.4 to 22.0 kg CO2-eq kg soybean-1, whereas life cycle EU and AD impacts varied by factors of 302 and 44, respectively. Nitrogen application rates, temperature in March and soil texture were the top influencing factors for life cycle GWP impacts. In contrast, soil organic content and nitrogen application rate were the top influencing factors for life cycle EU and AD impacts.

Projecting life-cycle environmental impacts of corn production in the U.S. Midwest under future climate scenarios using a machine learning approach

Climate change is exacerbating environmental pollution from crop production. Spatially and temporally explicit estimates of life-cycle environmental impacts are therefore needed for suggesting location and time relevant environmental mitigations strategies. Emission factors and process-based mechanism models are popular approaches used to estimate life-cycle environmental impacts. However, emission factors are often incapable of describing spatial and temporal heterogeneity of agricultural emissions, whereas process-based mechanistic models, capable of capturing the heterogeneity, tend to be very complicated and time-consuming. Efficient prediction of life-cycle environmental impacts from agricultural production is lacking. This study develops a rapid predictive model to quantify life-cycle global warming (GW) and eutrophication (EU) impacts of corn production using a novel machine learning approach. We used the boosted regression tree (BRT) model to estimate future life-cycle environmental impacts of corn production in U.S. Midwest counties under four emissions scenarios for years 2022-2100. Results from BRT models indicate that the cross-validation (R²) for predicting life cycle GW and EU impacts ranged from 0.78 to 0.82, respectively. Furthermore, results show that future life-cycle GW and EU impacts of corn production will increase in magnitude under all four emissions scenarios, with the highest environmental impacts shown under the high-emissions scenario. Moreover, this study found that changes in precipitation and temperature played a significant role in influencing the spatial heterogeneity in all life-cycle impacts across Midwest counties. The BRT model results indicate that machine learning can be a useful tool for predicting spatially and temporally explicit future life-cycle environmental impacts associated with corn production under different climate scenarios.

Lesion-Based Evaluation Predicts Treatment Response to Lenvatinib for Radioactive Iodine-Refractory Differentiated Thyroid Cancer: A Korean Multicenter Retrospective Study

Background: Lenvatinib, a tyrosine kinase inhibitor (TKI) recently approved for treating radioactive iodine-refractory differentiated thyroid cancer, has been shown to delay disease progression and provide meaningful benefit for overall survival (OS). However, there is no predictive marker for response to lenvatinib before initiating treatment. We comprehensively analyzed clinical and radiological parameters to predict response to lenvatinib using lesion-based assessments. Methods: Medical records were collected from 67 patients treated with lenvatinib in 11 referral hospitals across Korea from June 2015 to December 2017. Up to 96 measurable lesions, defined as per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, were evaluated serially until progressive disease (PD) occurred, and tumor doubling time (TDT) was calculated based on changes between historical computed tomography (CT) scans and baseline CT scans performed at treatment initiation. Results: Excluding patients with anaplastic thyroid cancer, no thyroidectomy, nontarget lesions only, or treatment periods of <1 month, 57 patients were analyzed, of whom 7 (12.2%) were TKI-naive. The median progression-free survival was 5.1 months (95% confidence interval [CI], 4.4-9.5), the median OS was 19.3 months (95% CI 12.4-not reached), the mean duration of response was 6.0 ± 4.4 months, and the objective response rate was 38%. In lesion-based assessments, 31 lesions (32.2%) with significant tumor shrinkage (complete remission or partial response) were significantly associated with shorter TDT (<12 months; p = 0.02). Patients with rapidly PD with a shorter initial TDT (<6 months) were more likely to respond to lenvatinib (p = 0.03). Patients exposed to lenvatinib at an average of ≥16 mg per day, or who were TKI-naive before treatment with lenvatinib, had a lower risk of progression; however, the risk reduction did not reach statistical significance (daily dosage p = 0.07, TKI exposure p = 0.09). Conclusions: TDT calculations at the beginning of treatment and lesion-based tumor assessment may help identify potential responders to lenvatinib therapy and predict therapeutic responses.

Incidence of Diabetes After Cancer Development: A Korean National Cohort Study

Importance

Diabetes is an established risk factor for developing cancer. A limited body of evidence also suggests that cancer can increase the risk of developing new cases of diabetes, but the evidence is inconclusive.

Objective

To evaluate whether the development of cancer is associated with increasing risk of subsequent diabetes.

Design, Setting, and Participants

This cohort study included a nationally representative sample of the Korean general population observed for up to 10 years (January 1, 2003, to December 31, 2013). A total of 524 089 men and women 20 to 70 years of age without diabetes and with no history of cancer at baseline were included.

Exposures

Incident cancer (time-varying exposure).

Main Outcomes and Measures

Incident type 2 diabetes using insurance claim codes.

Results

During 3 492 935.6 person-years of follow-up (median follow-up, 7.0 years) in 494 189 individuals (50.0% female; mean [SD] age, 41.8 [12.5] years), 15 130 participants developed cancer and 26 610 participants developed diabetes. After adjustment for age, sex, precancer diabetes risk factors, metabolic factors, and comorbidities, the hazard ratio (HR) for diabetes associated with cancer development was 1.35 (95% CI, 1.26-1.45; P < .001). The excess risk for diabetes was highest in the first 2 years after cancer diagnosis, but it remained elevated throughout follow-up. By cancer type, development of pancreatic (HR, 5.15; 95% CI, 3.32-7.99), kidney (HR, 2.06; 95% CI, 1.34-3.16), liver (HR, 1.95; 95% CI, 1.50-2.54), gallbladder (HR, 1.79; 95% CI, 1.08-2.98), lung (HR, 1.74; 95% CI, 1.34-2.24), blood (HR, 1.61; 95% CI, 1.07-2.43), breast (HR, 1.60; 95% CI, 1.27-2.01), stomach (HR, 1.35; 95% CI, 1.16-1.58), and thyroid cancer (HR, 1.33; 95% CI, 1.12-1.59) was associated with a significantly increased risk of diabetes.

Conclusions and Relevance

In this large Korean cohort, cancer development increased the risk of subsequent diabetes. These data provide evidence that cancer is associated with an increased risk of diabetes in cancer survivors independent of traditional diabetes risk factors. Physicians should remember that patients with cancer develop other clinical problems, such as diabetes, with higher frequency than individuals without cancer, and should consider routine diabetes screening in these patients.

Mono-PEGylates of exenatide in branched and dimeric structures can improve in vivo stability and hypoglycemic bioactivity

Exenatide, a synthetic version of exendin-4, is a glucagon-like peptide-1 receptor agonist (GLP-1RA) used for treating diabetes, but its relatively short half-life is a major disadvantage. In this study, we attempted residue-specific mono-PEGylation to the middle of the amino acid backbone to extend its in vivo half-life. Exenatide was point-mutated from Lys to Cys at the 12th residue to yield a variant (K12C), and PEG-maleimide of varying molecular weights (MW) (5, 10, 20, 40 kD) was site-specifically conjugated to yield a mono-PEGylate with branched T-shape molecular structure. In another approach, we conjugated a bis-maleimide PEG (10 kD) to the middle of two K12Cs to yield an H-shape homodimer PEGylate In vitro bioactivity assays indicated that: (1) PEGylates conjugated with higher MW PEG lead to stronger receptor binding, (2) the branched form was superior to the linear configuration in the binding, and (3) both T-shape and H-shape mono-PEGylates demonstrated better potency than the native exenatide, evidenced by lower EC₅₀. Db/db mouse experiments to evaluate in vivo hypoglycemic activity indicated that: (1) all mono-PEGylates resulted in improved glucose tolerance compared to the native exenatide, (2) the homodimer PEGylate demonstrated much stronger hypoglycemic activity, especially during the initial period, and (3) the H-shape and T-shape mono-PEGylates (40 kD) maintained hypoglycemia for up to ca. 168 and 140 h, representing approximately 12- and 14-fold increase, respectively, compared with the native exenatide. Our findings suggest that the exenatide mono-PEGylates in unclassical molecular structures can improve in vivo pharmacokinetics properties.

Longitudinal Assessment of Quality of Life According to Treatment Options in Low-Risk Papillary Thyroid Microcarcinoma Patients: Active Surveillance or Immediate Surgery (Interim Analysis of MAeSTro)

Background: In this ongoing multicenter prospective cohort study on active surveillance (AS) in low-risk papillary thyroid microcarcinoma (PTMC), we aimed to compare the quality of life (QoL) of participants based on their choice of treatment, that is, AS or immediate surgery (OP). Methods: QoL of 203 participants who chose AS and 192 participants who underwent OP was evaluated using a thyroid-specific QoL questionnaire at diagnosis and during follow-up (median 8 months). Results: The mean ages of the participants in the AS and OP groups were 47.3 ± 11.7 and 45.6 ± 10.5 years (p = 0.138), respectively, and the mean tumor sizes were 5.7 ± 1.6 and 6.5 ± 2.1 mm (p = 0.065), respectively. At baseline, significantly better psychological health (7.1 ± 1.3 vs. 6.8 ± 1.6, p = 0.023) and overall health (6.8 ± 1.2 vs. 6.5 ± 1.3, p = 0.018) were observed in the AS group than in the OP group. During follow-up, significantly better physical (7.9 ± 1.1 vs. 7.4 ± 1.2, p < 0.001), psychological (7.4 ± 1.3 vs. 6.9 ± 1.6, p = 0.004), and overall health (6.9 ± 1.0 vs. 6.5 ± 1.1, p = 0.002) were observed in the AS group than in the OP group, whereas spiritual health was comparable between the two groups. Compared with the AS group, the OP group experienced more fatigue, changes in voice and appearance, less satisfaction, and low fear of recurrence. The self-assessed financial burden was similar at baseline and follow-up in both groups. Conclusion: The QoL of PTMC patients is different according to the type of treatment. Better psychological health at baseline and physical and psychological health at follow-up were observed in the AS group than in the OP group. However, studies with longer follow-up periods are needed.