Report of the JDS/JCA Joint Committee on Diabetes and Cancer

Safety and effectiveness of tofogliflozin in Japanese people with type 2 diabetes: A multicenter prospective observational study in routine clinical practice

AIMS/INTRODUCTION

Sodium-glucose cotransporter 2 (SGLT2) inhibitors effectively and safely reduce fasting and postprandial hyperglycemia while promoting weight loss. However, their unique mechanism of action contributes to concerns regarding their safety. We therefore carried out a large-scale, non-commercial, investigator-initiated study on the safety and effectiveness of the SGLT2 inhibitor tofogliflozin.

MATERIALS AND METHODS

This multicenter, open-label, uncontrolled, prospective observational study was carried out at hospitals and clinics across Japan in participants aged ≥20 years who were SGLT2 inhibitor-naïve and had an established diagnosis of type 2 diabetes. The primary endpoint was adverse drug reactions (ADRs) of special interest. Secondary endpoints included all other ADRs and adverse events, glycated hemoglobin (HbA1c), and weight loss.

RESULTS

The study, carried out from June 2014 through February 2020, enrolled 11,480 participants from 1,103 medical institutions; 6,967 participants completed the 104-week follow up. The most common ADRs of special interest were urinary and genital tract infections (1.53%), followed by volume depletion (1.25%). Hypoglycemia occurred in 27 participants (0.24%), adverse events in 1,054 (9.18%) and ADRs in 645 (5.62%). HbA1c decreased by 0.85% (95% confidence interval 0.82%-0.88%) and bodyweight decreased by 3.05 kg (95% confidence interval 2.94-3.17 kg). The HbA1c target was achieved by 51.70% of participants for target HbA1c <7.0%, 85.3% for <8.0% and 5.4% for <6.0% at week 104.

CONCLUSIONS

Tofogliflozin was associated with only mild or moderate ADRs characteristic of SGLT2 inhibitors, with no unpredictable, new, serious, or high-incidence adverse events or ADRs. This independent study confirmed the safety and effectiveness of tofogliflozin in adult type 2 diabetes patients.

Third Report of the Japan Diabetes Society/Japanese Cancer Association Joint Committee on Diabetes and Cancer: Summary of the results of a questionnaire survey of oncologists and diabetologists-Secondary publication

The Japan Diabetes Society and the Japan Cancer Association launched a joint committee and published their "First Joint Committee Report on Diabetes and Cancer" in 2013, compiling recommendations for physicians and health-care providers as well as for the general population. In 2016, the "Second Joint Committee Report on Diabetes and Cancer" summarized the current evidence on glycemic control and cancer risk in patients with diabetes. The current "Third Joint Committee Report on Diabetes and Cancer", for which the joint committee also enlisted the assistance of the Japanese Society of Clinical Oncology and the Japanese Society of Medical Oncology, reports on the results from the questionnaire survey, "Diabetes Management in Patients Receiving Cancer Therapy," which targeted oncologists responsible for cancer management and diabetologists in charge of glycemic control in cancer patients. The results of the current survey indicated that there is a general consensus among oncologists and diabetologists with regard to the need for guidelines on glycemic control goals, the relevance of glycemic control, and glycemic control during cancer therapy in cancer patients.

Third Report of the Japan Diabetes Society (JDS)/Japanese Cancer Association (JCA) Joint Committee on diabetes and cancer: summary of the results of a questionnaire survey of oncologists and diabetologists-secondary publication

The Japan Diabetes Society (JDS) and the Japan Cancer Association (JCA) launched a joint committee and published their "First Joint Committee Report on Diabetes and Cancer" in 2013, compiling recommendations for physicians and healthcare providers as well as for the general population. In 2016, the "Second Joint Committee Report on Diabetes and Cancer" summarized the current evidence on glycemic control and cancer risk in patients with diabetes. The current "Third Joint Committee Report on Diabetes and Cancer", for which the joint committee also enlisted the assistance of the Japanese Society of Clinical Oncology (JSCO) and the Japanese Society of Medical Oncology (JSMO), reports on the results from the questionnaire survey, "Diabetes Management in Patients Receiving Cancer Therapy," which targeted oncologists responsible for cancer management and diabetologists in charge of glycemic control in cancer patients. The results of the current survey demonstrated that there is a general consensus among oncologists and diabetologists with regard to the need for guidelines on glycemic control goals, the relevance of glycemic control, and glycemic control during cancer therapy in cancer patients.

Clinical significance of tumor markers in patients with type 2 diabetes: a retrospective observational study

Aim

To cross-sectionally and longitudinally investigate the association between tumor markers (Cancer embryonic antigen (CEA) Carbohydrate antigen 19-9 (CA19-9)) and malignancies in type 2 diabetes patients without evidence of malignancy.

Materials and Methods

The study included 707 patients admitted for the treatment of diabetes from 1 August 2010 to 1 September 2018. Serum CEA and CA19-9 levels were measured for screening of malignancies at admission. Abdominal ultrasonography, computed tomography, and endoscopy were performed for close examination. The percentage of patients diagnosed with malignancy was calculated, and among those without malignancy, the incidence of malignancies was examined after discharge.

Results

A total of 26 patients (3.7%) were newly diagnosed with malignancy during hospitalization. The optimal cut-off value of CEA and CA19-9 by receiver operating characteristic analysis was 5.0 ng/mL and 75 U/mL, and their positive predictive values (PPV) were 8.7% and 22.5%, respectively. The addition of CA19-9 to age, smoking status, body mass index, and glycated hemoglobin significantly improved classification performance for malignancy using net reclassification improvement (0.682, 95% CI 0.256-1.107) and integrated discrimination improvement (0.150, 95% CI 0.007-0.294). Among 681 patients without malignancies during hospitalization, 30 patients (4.4%) developed malignancies during an average follow-up of 3.9 years. CA19-9 (hazard ratio: 1.005, 95% CI: 1.003-1.008) was associated with the development of malignancies.

Conclusions

PPV of serum CEA and CA19-9 for detecting malignancy was high in type 2 diabetes patients with poor glycemic control. Measuring CA19-9 was found to be valuable to cross-sectionally and longitudinally detect malignancies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-022-00594-x.

Time trends (2012-2020) in glycated hemoglobin and adherence to the glycemic targets recommended for elderly patients by the Japan Diabetes Society/Japan Geriatrics Society Joint Committee among memory clinic patients with diabetes mellitus

AIMS/INTRODUCTION

To investigate the changes in the glycated hemoglobin (HbA1c) levels and the relative status of the glycemic control related to the new glycemic targets recommended by the Japan Diabetes Society/Japan Geriatrics Society Joint Committee in 2016 in patients with diabetes mellitus visiting a memory clinic from 2012 to 2020.

MATERIALS AND METHODS

This cross-sectional study included 1,436 patients aged ≥65 years with diabetes. Patients were categorized into three categories as follows: category I, intact cognitive function and activities of daily living (ADL); category II, mild cognitive deficits or impaired instrumental ADL; and category III, moderate to severe cognitive impairment or impaired basic ADL. Trends in HbA1c levels, glycemic control status (optimally/poorly/excessively controlled) and proportion of individuals receiving drugs potentially associated with severe hypoglycemia among all patients and categories (I, II or III) from 2012 to 2020 were examined using linear, logistic and multinominal logistic regression models adjusted for confounding factors.

RESULTS

Between 2012 and 2020, the HbA1c levels, as well as the proportion of patients with poor glycemic control, increased, whereas the proportion of patients with excessive glycemic control and those receiving drugs potentially associated with severe hypoglycemia decreased.

CONCLUSIONS

Increased levels of HbA1c and decreased proportions of individuals under excessive glycemic control might reflect recent treatment strategies that avoid hypoglycemia in older patients. Given the adverse complications associated with hyperglycemia, more flexible and individualized glycemic targets based on comprehensive assessments, including vascular complications and comorbidities, might be necessary.

Combined treatment with glucagon-like peptide-1 receptor agonist exendin-4 and metformin attenuates breast cancer growth

Cancer is a major cause of death in patients with diabetes. Incretin therapy has received much attention because of its tissue-protective effects. We have previously reported an anti-breast cancer effect of glucagon-like peptide-1 receptor agonist exendin-4 (Ex-4). An anti-cancer effect of metformin is well recognized. Therefore, we examined the effect of combined treatment with Ex-4 and metformin in breast cancer cells. In human breast cancer cell lines MCF-7, MDA-MB-231, and KPL-1, 0.1-10 mM metformin significantly reduced the cell number in growth curve analysis in a dose-dependent manner. Furthermore, combined treatment with 0.1 mM metformin and 10 nM Ex-4 additively attenuated the growth curve progression of breast cancer cells. In a bromodeoxyuridine (BrdU) assay, Ex-4 or metformin significantly decreased breast cancer cell proliferation and further reduction of BrdU incorporation was observed by combined treatment with Ex-4 and metformin, which suggested that Ex-4 and metformin additively decreased DNA synthesis in breast cancer cells. Although apoptotic cells were not observed among Ex-4-treated breast cancer cells, apoptotic cells were clearly detected among metformin-treated breast cancer cells by apoptosis assays. Furthermore, metformin decreased BCL-2 expression in MCF-7 cells. In vivo experiments using a xenograft model showed that Ex-4 and metformin significantly decreased the breast tumor weight and Ki67-positive proliferative cancer cells, and metformin reduced the serum insulin level in mice. These data suggested that Ex-4 and metformin attenuated cell proliferation and metformin induced apoptosis in breast cancer cells. Combined treatment of Ex-4 and metformin may be an optional therapy to inhibit breast cancer progression.

Sodium-glucose cotransporter 2 inhibitor canagliflozin attenuates lung cancer cell proliferation in vitro

Cancer is a major cause of death in patients with type 2 diabetes mellitus (T2DM) and lung cancer is one of the most prevalent cancers in patients with T2DM. In the present study, we examined the anti-cancer effect of the Sodium-glucose cotransporter 2 (SGLT2) inhibitor, canagliflozin, using a lung cancer model. In lung cancer tissues from non-T2DM human subjects, SGLT2 was detected by immunohistochemistry. SGLT2 mRNA and protein were also detected in A549, H1975 and H520 lung cancer cell lines by RT-PCR and immunohistochemistry, respectively. Canagliflozin at 1-50 µM significantly suppressed the growth of A549 cells in a dose-dependent manner. In BrdU assays, canagliflozin attenuated the proliferation of A549 cells, but did not induce apoptosis. In cell cycle analysis, S phase entry was attenuated by canagliflozin in A549 cells. In in vivo experiments, a xenograft model of athymic mice implanted with A549 lung cancer cells was treated with low and high dose oral canagliflozin. Despite the results of the in vitro experiments, tumor weight was not decreased by canagliflozin. In addition, the serum insulin level, but not body weight or blood glucose level, was decreased by canagliflozin. The number of cells positive for Ki67 was slightly decreased by canagliflozin, but this was not statistically significant. In conclusion, SGLT2 is expressed in human lung cancer tissue and cell lines, and the SGLT2 inhibitor, canagliflozin, attenuated proliferation of A549 lung cancer cells by inhibiting cell cycle progression in vitro but not in vivo.

Association Between Statins and Cancer Incidence in Diabetes: a Cohort Study of Japanese Patients with Type 2 Diabetes

BACKGROUND

The antitumor effect of statins has been highlighted, but clinical study results remain inconclusive. While patients with diabetes are at high risk of cancer, it is uncertain whether statins are effective for cancer chemoprevention in this population.

OBJECTIVE

This study evaluated the association between statins and cancer incidence/mortality in patients with type 2 diabetes.

DESIGN

This study was a follow-up observational study of the Japanese Primary Prevention of Atherosclerosis with Aspirin for Diabetes (JPAD) trial, which was a randomized controlled trial of low-dose aspirin in Japanese patients with type 2 diabetes.

PARTICIPANTS

This study enrolled 2536 patients with type 2 diabetes, age 30-85 years, and no history of atherosclerotic cardiovascular disease, from December 2002 until May 2005. All participants recruited in the JPAD trial were followed until the day of any fatal event or July 2015. We defined participants taking any statin at enrollment as the statin group (n = 650) and the remainder as the no-statin group (n = 1886).

MAIN MEASURES

The primary end point was the first occurrence of any cancer (cancer incidence). The secondary end point was death from any cancer (cancer mortality).

KEY RESULTS

During follow-up (median, 10.7 years), 318 participants developed a new cancer and 123 died as a result. Cancer incidence and mortality were 10.5 and 3.7 per 1000 person-years in the statin group, and 16.8 and 6.3 per 1000 person-years in the no-statin group, respectively. Statin use was associated with significantly reduced cancer incidence and mortality after adjustment for confounding factors (cancer incidence: adjusted hazard ratio [HR], 0.67; 95% CI, 0.49-0.90, P = 0.007; cancer mortality: adjusted HR, 0.60; 95% CI, 0.36-0.98, P = 0.04).

CONCLUSIONS

Statin use was associated with a reduced incidence and mortality of cancer in Japanese patients with type 2 diabetes.

Activation of overexpressed glucagon-like peptide-1 receptor attenuates prostate cancer growth by inhibiting cell cycle progression

AIMS/INTRODUCTION

Incretin therapy is a common treatment for type 2 diabetes mellitus. We have previously reported an anti-prostate cancer effect of glucagon-like peptide-1 receptor (GLP-1R) agonist exendin-4. The attenuation of cell proliferation in the prostate cancer cell line was dependent on GLP-1R expression. Here, we examined the relationship between human prostate cancer severity and GLP-1R expression, as well as the effect of forced expression of GLP-1R using a lentiviral vector.

MATERIALS AND METHODS

Prostate cancer tissues were extracted by prostatectomy and biopsy. GLP-1R was overexpressed in ALVA-41 cells using a lentiviral vector (ALVA-41-GLP-1R cells). GLP-1R expression was detected by immunohistochemistry and quantitative polymerase chain reaction. Cell proliferation was examined by growth curves and bromodeoxyuridine incorporation assays. Cell cycle distribution and regulators were examined by flow cytometry and western blotting. In vivo experiments were carried out using a xenografted model.

RESULTS

GLP-1R expression levels were significantly inversely associated with the Gleason score of human prostate cancer tissues. Abundant GLP-1R expression and functions were confirmed in ALVA-41-GLP-1R cells. Exendin-4 significantly decreased ALVA-41-GLP-1R cell proliferation in a dose-dependent manner. DNA synthesis and G1-to-S phase transition were inhibited in ALVA-41-GLP-1R cells. SKP2 expression was decreased and p27Kip1 protein was subsequently increased in ALVA-41-GLP-1R cells treated with exendin-4. In vivo experiments carried out by implanting ALVA-41-GLP-1R cells showed that exendin-4 decreased prostate cancer growth by activation of GLP-1R overexpressed in ALVA41-GLP-1R cells.

CONCLUSIONS

Forced expression of GLP-1R attenuates prostate cancer cell proliferation by inhibiting cell cycle progression in vitro and in vivo. Therefore, GLP-1R activation might be a potential therapy for prostate cancer.

Increased cancer mortality among Japanese individuals with hyperinsulinemia

AIMS

To evaluate the effect of hyperinsulinemia on cancer death, we clarified the association between hyperinsulinemia and cancer mortality among Japanese individuals.

METHODS

All the participants (5586 men and 6652 women) lived in Hiroshima City, underwent a 75 g oral glucose tolerance test between 1994 and 2012, and were followed for mortality until August 2013. A systematic review of death certificates was used to confirm the cause of death.

RESULTS

During the follow-up period (median, 10.0 years), 587 participants died of cancer. Lung cancer was the most common cause of organ-specific death. We divided the participants into 3 groups according to the tertiles of fasting immunoreactive insulin (FIRI) levels (low, middle, and high groups). The high group had the highest mortality rate (5.5 per 1000 person-years). The hazard ratio (HR) for cancer mortality of the high group after adjustment for possible confounders, such as age, sex, body mass index, smoking status, alcohol intake, and radiation effects (model 1), was significantly higher than that of the low group (HR, 1.55; 95% confidence interval (CI), 1.23-1.95). In model 2 (model 1 plus fasting plasma glucose) and model 3 (model 1 plus HbA1c), the multivariate HRs for cancer mortality were 1.46 (95% CI, 1.15-1.85) and 1.48 (95% CI, 1.17-1.87), respectively.The HR for cancer death at high FIRI levels (per 1 μU/mL) was 1.04 (95% CI, 1.02-1.05) in all participants after adjusting for fasting plasma glucose level and other confounders. In the subgroup analysis, the HRs were 1.03 (95% CI, 0.98-1.09), 1.05 (95% CI, 1.02-1.08), and 1.04 (95% CI, 1.02-1.06) in the normal, prediabetes, and diabetes group, respectively.

CONCLUSIONS

Hyperinsulinemia was associated with a high risk of cancer mortality and may be an important link between cancer mortality and diabetes or prediabetes.

Long-Term Safety and Efficacy of Teneligliptin in Elderly Patients with Type 2 Diabetes: Subgroup Analysis of a 3-Year Post-Marketing Surveillance in Japan

INTRODUCTION

Teneligliptin, a dipeptidyl peptidase 4 inhibitor, was approved for the treatment of type 2 diabetes mellitus (T2DM) in Japan in 2012. However, clinical trials of teneligliptin involved limited numbers of elderly patients. Therefore, we investigated the safety and efficacy of teneligliptin in elderly patients with T2DM.

METHODS

This 3-year follow-up RUBY surveillance registered patients with T2DM who started treatment with teneligliptin between May 2013 and February 2015 in Japan. Collected data included demographics, treatments, adverse drug reactions (ADRs), and laboratory variables. Data were analysed for patients in three age subgroups (< 65, ≥ 65 to < 75, or ≥ 75 years old). Safety was assessed as the incidence of ADRs and efficacy was assessed in terms of glycaemic control, for up to 3 years.

RESULTS

The ADRs and serious ADRs occurred in 3.35% and 0.65% of 4596 patients aged < 65 years, in 4.42% and 1.22% of 3371 patients aged ≥ 65 to < 75 years, and in 3.99% and 1.69% of 2729 patients aged ≥ 75 years. The most common ADRs in patients aged ≥ 65 to < 75 years and ≥ 75 years were gastrointestinal disorders, but the incidence of these ADRs did not show an age-dependent increase. Hypoglycaemia occurred in 0.24%, 0.56%, and 0.29% of patients in each age subgroup, respectively. The least-squares mean changes in glycosylated haemoglobin (HbA1c) adjusted for baseline were - 0.66 ± 0.02% (n = 2177), - 0.72 ± 0.02% (n = 1689), and - 0.77 ± 0.03% (n = 1161) at 3 years.

CONCLUSION

There was no clear difference in the number of ADRs among the three age subgroups, although the incidence of serious ADRs was higher in elderly patients than in patients aged < 65 years. We found no additional safety or efficacy concerns among elderly patients beyond those already described in the package insert. The present results support the use of teneligliptin in elderly patients with T2DM in real-world clinical practice.

TRIAL REGISTRATION

Japic Clinical Trials Information identifier, Japic CTI-153047.

Long-Term, Real-World Safety and Efficacy of Teneligliptin: A Post-Marketing Surveillance of More Than 10,000 Patients with Type 2 Diabetes in Japan

INTRODUCTION

Teneligliptin is a dipeptidyl peptidase 4 inhibitor that was approved for the treatment of type 2 diabetes mellitus (T2DM) in Japan in 2012. We performed a long-term post-marketing surveillance (RUBY) to obtain real-world evidence regarding the safety and efficacy of teneligliptin in Japan.

METHODS

This 3-year follow-up RUBY surveillance registered patients with T2DM who started treatment with teneligliptin between May 2013 and February 2015 in Japan. Collected data included demographics, treatments, adverse drug reactions (ADRs) and laboratory variables. Data were evaluated in all patients and in patients divided according to baseline renal function across categories of estimated glomerular filtration rate (G1-G5) and dialysis. Safety was assessed as the incidence of ADRs and efficacy was assessed in terms of glycaemic control, for up to 3 years.

RESULTS

Of 11,677 patients registered, 10,696 and 10,249 were evaluable for safety and efficacy analyses, respectively. The median duration of exposure was 1096 days. ADRs occurred in 412 patients (3.85%) and were serious in 117 patients (1.09%). The most frequent ADR class was gastrointestinal disorders (0.68%), which included constipation. There were no new ADRs warranting attention beyond those already described in teneligliptin's package insert. ADRs and serious ADRs in renal function subgroups occurred in 3.24-7.14% and 0.65-5.36% in G1-G5, and 4.49% and 1.92% in patients on dialysis, respectively. Reduction in HbA1c was sustained for 3 years after starting teneligliptin (- 0.70% ± 1.36%, p < 0.001 at 3 years). The least-squares mean changes in HbA1c adjusted for baseline were - 0.76% to - 0.66% in G1-G5 at 3 years. Glycated albumin levels decreased in patients on dialysis (- 2.92% ± 4.78% at 3 years).

CONCLUSION

There were no new safety or efficacy concerns about teneligliptin used in long-term, real-world, clinical settings in patients with T2DM with any stages of renal impairment.

TRIAL REGISTRATION

Japan Pharmaceutical Information Center clinical trials database identifier: Japic CTI-153047. Plain language summary available for this article.

SGLT2 inhibitor ipragliflozin attenuates breast cancer cell proliferation

Cancer is currently one of the major causes of death in patients with type 2 diabetes mellitus. We previously reported the beneficial effects of the glucagon-like peptide-1 receptor agonist exendin-4 against prostate and breast cancer. In the present study, we examined the anti-cancer effect of the sodium-glucose cotransporter 2 (SGLT2) inhibitor ipragliflozin using a breast cancer model. In human breast cancer MCF-7 cells, SGLT2 expression was detected using both RT-PCR and immunohistochemistry. Ipragliflozin at 1-50 μM significantly and dose-dependently suppressed the growth of MCF-7 cells. BrdU assay also revealed that ipragliflozin attenuated the proliferation of MCF-7 cells in a dose-dependent manner. Because the effect of ipragliflozin against breast cancer cells was completely canceled by knocking down SGLT2, ipragliflozin could act via inhibiting SGLT2. We next measured membrane potential and whole-cell current using the patch clamp technique. When we treated MCF-7 cells with ipragliflozin or glucose-free medium, membrane hyperpolarization was observed. In addition, glucose-free medium and knockdown of SGLT2 by siRNA suppressed the glucose-induced whole-cell current of MCF-7 cells, suggesting that ipragliflozin inhibits sodium and glucose cotransport through SGLT2. Furthermore, JC-1 green fluorescence was significantly increased by ipragliflozin, suggesting the change of mitochondrial membrane potential. These findings suggest that the SGLT2 inhibitor ipragliflozin attenuates breast cancer cell proliferation via membrane hyperpolarization and mitochondrial membrane instability.

Prospective study of cancer in Japanese patients with type 2 diabetes: the Fukuoka Diabetes Registry

Background

Although the association between type 2 diabetes and cancer has been reported, few epidemiological studies have been conducted in Japanese patients whose leading cause of death is cancer. We prospectively studied the incidence of site-specific cancer, risk factors for developing cancer, cancer death, and survival in Japanese patients with type 2 diabetes.

Methods

We followed 4923 participants (mean age, 65 years) with type 2 diabetes attending an outpatient diabetes clinic for a median of 5.3 years (follow-up rate, 99.0%).

Results

During the follow-up period, cancer occurred in 450 participants (incidence rate, 22.3/1000 person-years in men and 12.2/1000 person-years in women). In men, prostate cancer was the most common cancer (4.3/1000 person-years), colorectal cancer was the second (3.6/1000 person-years), and gastric cancer was the third (3.3/1000 person-years). In women, colorectal cancer was the most common cancer (2.6/1000 person-years), gastric cancer was the second (2.0/1000 person-years), and breast cancer was the third (1.4/1000 person-years). Smoking, male sex, low-density lipoprotein cholesterol, family history of cancer, and reduced intake of isoflavone daidzein were significant risk factors for developing cancer using multivariable Cox proportional hazards models. The leading cancer death was lung cancer in men and pancreatic cancer in women. The survival was the best for prostate cancer and the worst for pancreatic cancer (2-year cancer-specific survival 95.4%, 30.0%, respectively).

Conclusions

Since the leading cause of death in patients with type 2 diabetes is cancer in Japan, clinicians should be aware of epidemiological data regarding cancer besides diabetic complications.

Association between postprandial hyperglycemia at clinic visits and all-cause and cancer mortality in patients with type 2 diabetes: A long-term historical cohort study in Japan

AIMS

To evaluate the effect of postprandial hyperglycemia at clinic visits on all-cause and cancer mortality independent of glycated hemoglobin (HbA1c) levels in a real-world setting in Japanese patients with type 2 diabetes. We also investigated age at death.

METHODS

This historical cohort study included 1582 patients with type 2 diabetes who first visited our clinic from 1995 to 1998 and continued visiting for at least 1 year. The patients were followed up through 2017. Blood glucose levels at 2 h ± 30 min post-breakfast (2h-PBBG) were measured in 926 patients during the first year. The first measurements of 2h-PBBG levels were used as a measure of postprandial hyperglycemia.

RESULTS

A total of 233 patients died. The average age at death (men/women) was 75.6/80.8 years. A total of 139 patients who had 2h-PBBG levels measured died, including 46 deaths from cancer. Multivariate Cox regression analysis showed that 2h-PBBG levels significantly predicted all-cause and cancer mortality independent of HbA1c levels.

CONCLUSIONS

Postprandial hyperglycemia at clinic visits may be associated with all-cause and cancer mortality in patients with type 2 diabetes independent of HbA1c levels. As this is a small observational study, further studies are warranted to confirm our findings.

Effect of Aspirin on Cancer Chemoprevention in Japanese Patients With Type 2 Diabetes: 10-Year Observational Follow-up of a Randomized Controlled Trial

OBJECTIVE

This study analyzed the efficacy of low-dose aspirin in cancer chemoprevention in patients with diabetes.

RESEARCH DESIGN AND METHODS

This study was a posttrial follow-up of the Japanese Primary Prevention of Atherosclerosis with Aspirin for Diabetes (JPAD) trial. Participants in the JPAD trial (2,536 Japanese patients with type 2 diabetes and without preexisting cardiovascular disease) were randomly allocated to receive aspirin (81 or 100 mg daily) or no aspirin. After that trial ended in 2008, we followed up with the participants until 2015, with no attempt to change the previously assigned therapy. The primary end point was total cancer incidence. We investigated the effect of low-dose aspirin on cancer incidence.

RESULTS

During the median follow-up period of 10.7 years, a total of 318 cancers occurred. The cancer incidence was not significantly different between the aspirin and no-aspirin groups (log-rank, P = 0.4; hazard ratio [HR], 0.92; 95% CI, 0.73-1.14; P = 0.4). In subgroup analyses, aspirin did not affect cancer incidence in men, women, or participants aged ≥65 years. However, it decreased cancer incidence in participants aged <65 years (log-rank, P = 0.05; HR, 0.67; 95% CI, 0.44-0.99; P = 0.048). After adjusting for sex, hemoglobin A_1c, smoking status, and administration of metformin and statins, aspirin significantly reduced cancer incidence in participants aged <65 years (adjusted HR, 0.66; 95% CI, 0.43-0.99; P = 0.04).

CONCLUSIONS

Low-dose aspirin did not reduce cancer incidence in Japanese patients with type 2 diabetes.

Exendin-4, a Glucagonlike Peptide-1 Receptor Agonist, Attenuates Breast Cancer Growth by Inhibiting NF-κB Activation

Incretin therapies have received much attention because of their tissue-protective effects, which extend beyond those associated with glycemic control. Cancer is a primary cause of death in patients who have diabetes mellitus. We previously reported antiprostate cancer effects of the glucagonlike peptide-1 (GLP-1) receptor (GLP-1R) agonist exendin-4 (Ex-4). Breast cancer is one of the most common cancers in female patients who have type 2 diabetes mellitus and obesity. Thus, we examined whether GLP-1 action could attenuate breast cancer. GLP-1R was expressed in human breast cancer tissue and MCF-7, MDA-MB-231, and KPL-1 cell lines. We found that 0.1 to 10 nM Ex-4 significantly decreased the number of breast cancer cells in a dose-dependent manner. Although Ex-4 did not induce apoptosis, it attenuated breast cancer cell proliferation significantly and dose-dependently. However, the dipeptidyl peptidase-4 inhibitor linagliptin did not affect breast cancer cell proliferation. When MCF-7 cells were transplanted into athymic mice, Ex-4 decreased MCF-7 tumor size in vivo. Ki67 immunohistochemistry revealed that breast cancer cell proliferation was significantly reduced in tumors extracted from Ex-4-treated mice. In MCF-7 cells, Ex-4 significantly inhibited nuclear factor κB (NF-κB ) nuclear translocation and target gene expression. Furthermore, Ex-4 decreased both Akt and IκB phosphorylation. These results suggest that GLP-1 could attenuate breast cancer cell proliferation via activation of GLP-1R and subsequent inhibition of NF-κB activation.

Design of and rationale for the Japan Diabetes compREhensive database project based on an Advanced electronic Medical record System (J-DREAMS)

The "Japan Diabetes compREhensive database project based on an Advanced electronic Medical record System" is a registry of patients with diabetes in Japan. The characteristics of this registry include a clinical information input process using the template function of an electronic medical record (EMR) system [the standard diabetes management template (SDMT)], a standardized exchangeable information storage format [the Standardized Structured Medical Information eXchange 2 (SS-MIX2)], and a secure and efficient information extraction process [Multipurpose Clinical Data Repository System (MCDRS)]. Together, these characteristics enable efficient data input during routine patient consultations, efficient and exact data extraction from each facility, and the integration of data across different facilities even though these data were generated by EMR systems from different vendors. The SDMT collects clinical information including the type of diabetes, body height and weight, blood pressure, lifestyle, and comorbidities. Completing this template triggers the automatic collection of other information such as fundamental information (sex, year and month of birth, and facility), prescription information, and laboratory examination results. As the information from every routine consultation is saved with an anonymized patient ID, linked data can be used as panel data allowing longitudinal investigations. The data obtained from the registry will allow analyses, for exmaple, mortality and morbidity risk, by various characteristics or drug types and may reveal unmet needs that inform future diabetes care.

Body mass index and the risk of cancer incidence in patients with type 2 diabetes in Japan: Results from the National Center Diabetes Database

AIMS/INTRODUCTION

Both type 2 diabetes and obesity increase the risk of some types of cancers, and underlying mechanisms are thought to be, at least in part, common. In the present study, we carried out a retrospective cohort study of the relationship between body mass index (BMI) categories and cancer development in Japanese type 2 diabetic patients.

MATERIALS AND METHODS

A total of 113 incident cancers including 35 cancers whose incidence was reported to be increased by obesity (27 colorectal cancers, two breast cancers in postmenopausal women, one endometrial cancer, four renal cancers and one gallbladder cancer) were identified in 2,334 type 2 diabetic patients (1,616 men and 718 women) over an average observation period of 5.1 years.

RESULTS

In men, there was no significant association between the BMI categories at the start of the observation period and the development of any cancer. In contrast, the incidence of all of the cancers in the women was significantly higher in the group with a BMI of less than 22.0 kg/m2 (hazard ratio 3.07, 95% CI 1.01-9.36). In either sex, there was no significant relationship between the BMI categories and the development of cancers whose risk is known to be increased by obesity.

CONCLUSIONS

The findings of the present study were limited by the relatively small number of patients in the cohort, which posed a danger of not finding significance. However, the results suggested that obesity did not become an additional risk factor for cancer in Japanese type 2 diabetic patients.

Combination of type 2 diabetes and smoking increases total cancer mortality in Japanese men using competing risk analysis: the Tanno-Sobetsu study

AIMS

We assessed the impact of the combination of type 2 diabetes (T2DM) and smoking on total cancer mortality using cohort data of a general Japanese population.

METHODS

Of 1908 residents who received health checkups in two towns in 1994, 794 males were included as study participants. Smoking status was defined as three categories: never smoker, ex-smoker and current smoker. Individuals with T2DM were defined as individuals with fasting plasma glucose ≥7.0 mmol/l and/or receiving medication for T2DM. Participants were divided into six groups according to T2DM and smoking status: non-DM (NDM) and never smoker, NDM and ex-smoker, NDM and current smoker, DM and never smoker, DM and ex-smoker, and DM and current smoker groups. All participants were followed up for a maximum of 13 years. We calculated the hazard ratio (HR) using Cox's proportional hazard model and subhazard ratio (SHR) using competing risk regression analyses in each group.

RESULTS

During the follow-up period, there were 169 all-cause deaths (62 cancer deaths and 40 CVD deaths). When using Cox regression analysis, HRs were higher in the ex-smoker and current smoker groups than in the never-smoker group, and HRs were also higher in the DM groups than in the NDM groups. When using competing risk analysis, SHRs were almost the same as the HRs of Cox regression analysis (DM and ex-smoker 6.06, DM and current smoker 10.12).

CONCLUSIONS

The combination of T2DM and smoking is a strong risk factor for total cancer mortality in Japanese men.

Report of the Japan Diabetes Society (JDS)/Japanese Cancer Association (JCA) Joint Committee on Diabetes and Cancer, Second Report

The Japan Diabetes Society (JDS)/Japanese Cancer Association (JCA) Joint Committee on Diabetes and Cancer published its first report in July 2013 on the epidemiological assessment of the associations of diabetes with cancer risk/prognosis, the common risk factors for diabetes and cancer, and cancer risk associated with diabetes treatment The JDS/JCA Joint Committee continued its work to assess the role of glycemic control in the development of cancer in patients with diabetes. This review shows that high-quality evidence examining the association between glycemic control and cancer risk is lacking.

Combined Treatment with Exendin-4 and Metformin Attenuates Prostate Cancer Growth

INTRODUCTION

Recently, the pleiotropic benefits of incretin-based therapy have been reported. We have previously reported that Exendin-4, a glucagon-like peptide-1 (GLP-1) receptor agonist, attenuates prostate cancer growth. Metformin is known for its anti-cancer effect. Here, we examined the anti-cancer effect of Exendin-4 and metformin using a prostate cancer model.

METHODS

Prostate cancer cells were treated with Exendin-4 and/or metformin. Cell proliferation was quantified by growth curves and 5-bromo-2'-deoxyuridine (BrdU) assay. TUNEL assay and AMP-activated protein kinase (AMPK) phosphorylation were examined in LNCaP cells. For in vivo experiments, LNCaP cells were transplanted subcutaneously into the flank region of athymic mice, which were then treated with Exendin-4 and/or metformin. TUNEL assay and immunohistochemistry were performed on tumors.

RESULTS

Exendin-4 and metformin additively decreased the growth curve, but not the migration, of prostate cancer cells. The BrdU assay revealed that both Exendin-4 and metformin significantly decreased prostate cancer cell proliferation. Furthermore, metformin, but not Exendin-4, activated AMPK and induced apoptosis in LNCaP cells. The anti-proliferative effect of metformin was abolished by inhibition or knock down of AMPK. In vivo, Exendin-4 and metformin significantly decreased tumor size, and further significant tumor size reduction was observed after combined treatment. Immunohistochemistry on tumors revealed that the P504S and Ki67 expression decreased by Exendin-4 and/or metformin, and that metformin increased phospho-AMPK expression and the apoptotic cell number.

CONCLUSION

These data suggest that Exendin-4 and metformin attenuated prostate cancer growth by inhibiting proliferation, and that metformin inhibited proliferation by inducing apoptosis. Combined treatment with Exendin-4 and metformin attenuated prostate cancer growth more than separate treatments.

Exendin-4, a GLP-1 receptor agonist, attenuates prostate cancer growth

Recently, pleiotropic benefits of incretin therapy beyond glycemic control have been reported. Although cancer is one of the main causes of death in diabetic patients, few reports describe the anticancer effects of incretin. Here, we examined the effect of the incretin drug exendin (Ex)-4, a GLP-1 receptor (GLP-1R) agonist, on prostate cancer. In human prostate cancer tissue obtained from patients after they had undergone radical prostatectomy, GLP-1R expression colocalized with P504S, a marker of prostate cancer. In in vitro experiments, Ex-4 significantly decreased the proliferation of the prostate cancer cell lines LNCap, PC3, and DU145, but not that of ALVA-41. This antiproliferative effect depended on GLP-1R expression. In accordance with the abundant expression of GLP-1R in LNCap cells, a GLP-1R antagonist or GLP-1R knockdown with small interfering RNA abolished the inhibitory effect of Ex-4 on cell proliferation. Although Ex-4 had no effect on either androgen receptor activation or apoptosis, it decreased extracellular signal-regulated kinase (ERK)-mitogen-activated protein kinase (MAPK) phosphorylation in LNCap cells. Importantly, Ex-4 attenuated in vivo prostate cancer growth induced by transplantation of LNCap cells into athymic mice and significantly reduced the tumor expression of P504S, Ki67, and phosphorylated ERK-MAPK. These data suggest that Ex-4 attenuates prostate cancer growth through the inhibition of ERK-MAPK activation.