Involvement of α-klotho in growth hormone (GH) signaling.

Growth hormone (GH) exerts multiple effects on different organs directly or via its main mediator, insulin-like growth factor1 (IGF1). In this study, we focused on the novel relationship between GH action and the antiaging hormone α-klotho. Immunofluorescent staining of α-klotho was observed in the renal distal tubules and pituitary glands of somatostatin- and GH-positive cells in wild-type (WT) mice. Treatment of 4-week-old WT mice with GH increased IGF1 mRNA expression in the pituitary gland, liver, heart, kidney, and bone but increased α-klotho mRNA expression only in the pituitary gland, kidney, and bone. Increased α-klotho protein levels were observed in the kidney but not in the pituitary gland. No induction of α-klotho RNA expression by GH was observed in juvenile mice with kidney disease, indicating GH resistance. Furthermore, GH and α-klotho supplementation in HEK293 cells transfected with GHR increased Janus kinase 2 mRNA (a GH downstream signal) expression compared to supplementation with GH alone. In conclusion, we suggest that 1) the kidney is the main source of secreted α-klotho, which is detected in blood by the downstream action of GH, 2) α-klotho induction by GH is resistant in kidney disease, and 3) α-klotho might be an enhanced regulator of GH signaling.

Common Dietary Sources of Natural and Artificial Phosphate in Food.

The Recommended Dietary Allowance (RDA) for phosphate in the U.S. is around 700 mg/day for adults. The majority of healthy adults consume almost double the amount of phosphate than the RDA. Lack of awareness, and easy access to phosphate-rich, inexpensive processed food may lead to dietary phosphate overload with adverse health effects, including cardiovascular diseases, kidney diseases and tumor formation. Nutritional education and better guidelines for reporting phosphate content on ingredient labels are necessary, so that consumers are able to make more informed choices about their diets and minimize phosphate consumption. Without regulatory measures, dietary phosphate toxicity is rapidly becoming a global health concern, and likely to put enormous physical and financial burden to the society.

HLA genotyping in Japanese patients with multiple myeloma receiving bortezomib: An exploratory biomarker study of JCOG1105 (JCOG1105A1).

Bortezomib (Btz) shows robust efficacy in patients with multiple myeloma (MM); however, some patients experience suboptimal responses and show specific toxicities. Therefore, we attempted to identify specific HLA alleles associated with Btz-related toxicities and response to treatment. Eighty-two transplant-ineligible patients with newly diagnosed MM enrolled in a phase II study (JCOG1105) comparing two less intensive melphalan, prednisolone, plus Btz (MPB) regimens were subjected to HLA typing. The frequency of each allele was compared between the groups, categorized based on toxicity grades and responses to MPB therapy. Among 82 patients, the numbers of patients with severe peripheral neuropathy (PN; grade 2 or higher), skin disorders (SD; grade 2 or higher), and pneumonitis were 16 (19.5%), 15 (18.3%), and 6 (7.3%), respectively. Complete response was achieved in 10 (12.2%) patients. Although no significant HLA allele was identified by multiple comparisons, several candidates were identified. HLA-B*40:06 was more prevalent in patients with severe PN than in those with less severe PN (odds ratio [OR] = 6.76). HLA-B*40:06 and HLA-DRB1*12:01 were more prevalent in patients with SD than in those with less severe SD (OR = 7.47 and OR = 5.55, respectively). HLA-DRB1*08:02 clustered in the group of patients with pneumonitis (OR = 11.34). Complete response was achieved in patients carrying HLA-DQB1*03:02, HLA-DQB1*05:01, and HLA-DRB1*01:01 class II alleles. HLA genotyping could help predict Btz-induced toxicity and treatment efficacy in patients with MM, although this needs further validation.

Evidence of an intestinal phosphate transporter alternative to type IIb sodium-dependent phosphate transporter in rats with chronic kidney disease.

BACKGROUND: Phosphate is absorbed in the small intestine via passive flow and active transport.NaPi-IIb, a type II sodium-dependent phosphate transporter, is considered to mediate active phosphate transport in rodents. To study the regulation of intestinal phosphate transport in chronic kidney disease (CKD), we analyzed the expression levels of NaPi-IIb, pituitary-specific transcription factor 1 (PiT-1) and PiT-2 and the kinetics of intestinal phosphate transport using two CKD models. METHODS: CKD was induced in rats via adenine orThy1 antibody injection. Phosphate uptake by intestinal brush border membrane vesicles (BBMV) and the messenger RNA (mRNA) expression of NaPi-IIb, PiT-1 and PiT-2 were analyzed. The protein expression level of NaPi-IIb was measured by mass spectrometry (e.g. liquid chromatography tandem mass spectrometry). RESULTS: In normal rats, phosphate uptake into BBMV consisted of a single saturable component and its Michaelis constant (Km) was comparable to that of NaPi-IIb. The maximum velocity (Vmax) correlated with mRNA and protein levels of NaPi-IIb. In the CKD models, intestinal phosphate uptake consisted of two saturable components. The Vmax of the higher-affinity transport, which is thought to be responsible for NaPi-IIb, significantly decreased and the decrease correlated with reduced NaPi-IIb expression. The Km of the lower-affinity transport was comparable to that of PiT-1 and -2. PiT-1 mRNA expression was much higher than that of PiT-2, suggesting that PiT-1 was mostly responsible for phosphate transport. CONCLUSIONS: This study suggests that the contribution of NaPi-IIb to intestinal phosphate absorption dramatically decreases in rats with CKD and that a low-affinity alternative to NaPi-IIb, in particular PiT-1, is upregulated in a compensatory manner in CKD.

Stage III disease of ovarian, tubal and peritoneal cancers can be accurately diagnosed with pre-operative CT. Japan Clinical Oncology Group Study JCOG0602.

PURPOSE: Computed tomography of the abdomen and pelvis is a useful imaging modality for identifying origin and extent of ovarian cancer before primary debulking surgery. However, the International Federation of Gynecology and Obstetrics staging for ovarian cancer is determined based on surgico-pathological findings. The purpose of this study is to determine whether computed tomography staging can be the surrogate for surgico-pathological International Federation of Gynecology and Obstetrics staging in advanced ovarian cancer undergoing neoadjuvant chemotherapy. METHODS: Computed tomography staging was compared with surgico-pathological International Federation of Gynecology and Obstetrics staging in primary debulking surgery arm patients in a randomized controlled trial comparing primary debulking surgery and neoadjuvant chemotherapy (JCOG0602). The cancer of primary debulking surgery arm was identically diagnosed regarding the origin and extent with the cancer of neoadjuvant chemotherapy arm before accrual, using imaging studies (computed tomography and/or magnetic resonance imaging), cytological examination (ascites, pleural effusion or tumor contents fluid) and tumor marker (CA125 > 200 U/mL and CEA < 20 ng/mL). Institutional computed tomography staging was also compared with computed tomography staging by central review. RESULTS: Among 149 primary debulking surgery arm patients, 147 patients who underwent primary debulking surgery immediately were analyzed. Positive predictive values and sensitivity of computed tomography staging for surgical stage III disease (extra-pelvic peritoneal disease and/or retroperitoneal lymph node metastasis) were 99%. Meanwhile, positive predictive values for the presence of small (≤2 cm) extra-pelvic peritoneal disease were low; <20% in omentum. Accuracy of institutional computed tomography staging was comparable with computed tomography staging by central review. CONCLUSIONS: Preoperative computed tomography staging in each institution can be the surrogate for surgico-pathological diagnosis in stage III disease of ovarian cancer patients undergoing neoadjuvant chemotherapy without diagnostic surgery, but reliability of diagnosis of stage IIIB disease is inadequate.Clinical trial registration: UMIN000000523(UMIN-CTR).

Comparison of the International Workshop Criteria and the Response Evaluation Criteria in Solid Tumors for indolent B-cell lymphoma.

BACKGROUND: [18F] fluorodeoxyglucose-positron emission tomography is incorporated in response criteria currently used for lymphoma; however, the primary endpoint in earlier phase study is an overall response, which includes the partial response of 50% shrinkage in two dimensions. Therefore, the measurement of target lesions is still prerequisite to determine the destiny of new, promising agents. Since required is calculating the sum of the product of bidimensional diameters of maximal six target lesions, the International Workshop Criteria (IWC) used as response evaluation in lymphoma is more time-consuming than the Response Evaluation Criteria in Solid Tumors (RECIST). This study aimed to examine whether the RECIST could replace the IWC using data from a phase II/III study of R-CHOP-21 versus R-CHOP-14 for advanced-stage indolent B-cell lymphoma, JCOG0203. METHODS: To evaluate the degree of agreement between them, the Kappa coefficient (KC) was calculated. Excluding patients without target lesions for the RECIST following central pathological review, 269 patients were evaluable. We determined which criterion was more predictive for progression-free survival. The criterion showing the lower point estimate of the hazard ratio (HR) of a complete response (CR) vs. a non-CR was defined as more useful. RESULTS: The KC between them was 0.34 (95% confidence interval [CI] 0.26-0.42); namely, indicating poor agreement. The HR of the IWC (0.47: 95% CI 0.33-0.68, log-rank test p < 0.001) was lower than that of the RECIST (0.64: 95% CI 0.45-0.89, p = 0.0075). CONCLUSION: We conclude that unidimensional measurements cannot be substituted for the bidimensional ones for indolent lymphoma.

Cutting Edge Molecular Therapy for Acute Myeloid Leukemia.

Recently, whole exome sequencing for acute myeloid leukemia (AML) has been performed by a next-generation sequencer in several studies. It has been revealed that a few gene mutations are identified per AML patient. Some of these mutations are actionable mutations that affect the response to an approved targeted treatment that is available for off-label treatment or that is available in clinical trials. The era of precision medicine for AML has arrived, and it is extremely important to detect actionable mutations relevant to treatment decision-making. However, the percentage of actionable mutations found in AML is about 50% at present, and therapeutic development is also needed for AML patients without actionable mutations. In contrast, the newly approved drugs are less toxic than conventional intensive chemotherapy and can be combined with low-intensity treatments. These combination therapies can contribute to the improvement of prognosis, especially in elderly AML patients who account for more than half of all AML patients. Thus, the treatment strategy for leukemia is changing drastically and showing rapid progress. In this review, we present the latest information regarding the recent development of treatment for AML.

Hereditary hypophosphatemic rickets with hypercalciuria: pathophysiology, clinical presentation, diagnosis and therapy.

Hereditary hypophosphatemic rickets with hypercalciuria (HHRH; OMIM: 241530) is a rare autosomal recessive disorder with an estimated prevalence of 1:250,000 that was originally described by Tieder et al. Individuals with HHRH carry compound-heterozygous or homozygous (comp/hom) loss-of-function mutations in the sodium-phosphate co-transporter NPT2c. These mutations result in the development of urinary phosphate (Pi) wasting and hypophosphatemic rickets, bowing, and short stature, as well as appropriately elevated 1,25(OH)2D levels, which sets this fibroblast growth factor 23 (FGF23)-independent disorder apart from the more common X-linked hypophosphatemia. The elevated 1,25(OH)2D levels in turn result in hypercalciuria due to enhanced intestinal calcium absorption and reduced parathyroid hormone (PTH)-dependent calcium-reabsorption in the distal renal tubules, leading to the development of kidney stones and/or nephrocalcinosis in approximately half of the individuals with HHRH. Even heterozygous NPT2c mutations are frequently associated with isolated hypercalciuria (IH), which increases the risk of kidney stones or nephrocalcinosis threefold in affected individuals compared with the general population. Bone disease is generally absent in individuals with IH, in contrast to those with HHRH. Treatment of HHRH and IH consists of monotherapy with oral Pi supplements, while active vitamin D analogs are contraindicated, mainly because the endogenous 1,25(OH)2D levels are already elevated but also to prevent further worsening of the hypercalciuria. Long-term studies to determine whether oral Pi supplementation alone is sufficient to prevent renal calcifications and bone loss, however, are lacking. It is also unknown how therapy should be monitored, whether secondary hyperparathyroidism can develop, and whether Pi requirements decrease with age, as observed in some FGF23-dependent hypophosphatemic disorders, or whether this can lead to osteoporosis.

NAD metabolism and the SLC34 family: evidence for a liver-kidney axis regulating inorganic phosphate.

The solute carrier 34 (SLC34) family of membrane transporters is a major contributor to Pi homeostasis. Many factors are involved in regulating the SLC34 family. The roles of the bone mineral metabolism factors parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) in Pi homeostasis are well studied. Intracellular Pi is thought to be involved in energy metabolism, such as ATP production. Under certain conditions of altered energy metabolism, plasma Pi concentrations are affected by the regulation of a Pi shift into cells or release from the tissues. We recently investigated the mechanism of hepatectomy-related hypophosphatemia, which is thought to involve an unknown phosphaturic factor. Hepatectomy-related hypophosphatemia is due to impaired nicotinamide adenine dinucleotide (NAD) metabolism through its effects on the SLC34 family in the liver-kidney axis. The oxidized form of NAD, NAD+, is an essential cofactor in various cellular biochemical reactions. Levels of NAD+ and its reduced form NADH vary with the availability of dietary energy and nutrients. Nicotinamide phosphoribosyltransferase (Nampt) generates a key NAD+ intermediate, nicotinamide mononucleotide, from nicotinamide and 5-phosphoribosyl 1-pyrophosphate. The liver, an important organ of NAD metabolism, is thought to release metabolic products such as nicotinamide and may control NAD metabolism in other organs. Moreover, NAD is an important regulator of the circadian rhythm. Liver-specific Nampt-deficient mice and heterozygous Nampt mice have abnormal daily plasma Pi concentration oscillations. These data indicate that NAD metabolism in the intestine, liver, and kidney is closely related to Pi metabolism through the SLC34 family. Here, we review the relationship between the SLC34 family and NAD metabolism based on our recent studies.

Systemic network for dietary inorganic phosphate adaptation among three organs.

Inorganic phosphate (Pi) secretion from the salivary glands and dietary Pi are key Pi sources. The regulatory mechanisms of Pi homeostasis in the salivary glands are unknown. We investigated how salivary Pi concentrations are regulated by dietary Pi in mouse models. Dietary manipulation significantly changed the levels of Npt2b protein in the salivary gland ductal cells. In addition, rapid feeding on a high-Pi diet increased the saliva Pi concentrations and led to rapid endocytosis of Npt2b in the apical membranes of the duct cells. Global Npt2b± mice exhibited increased salivary Pi concentrations and intestine-specific deletion of Npt2b after high Pi loading increased the salivary Pi concentrations. These findings indicate that Npt2b levels in the salivary glands affect the salivary Pi concentration and are regulated by dietary Pi. Intestinal Npt2b levels might also affect salivary Pi concentrations as well as renal Pi excretion. These findings suggest Pi is endogenously recycled by salivary Pi secretion, intestinal Pi absorption, and renal Pi excretion.

Study risk assessment of Japan Clinical Oncology Group (JCOG) clinical trials using the European Organisation for Research and Treatment of Cancer (EORTC) study risk calculator.

BACKGROUND: New Japanese ethical guidelines for medical researches and the Clinical Trials Act have come into effect and monitoring is mandated for intervention studies. Methods of monitoring can be modified according to a study risk, but there is no established method in Japan regarding how to assess a study risk. EORTC assesses a study risk using their own study risk calculator and classifies their trials into three categories. For each category, different levels of monitoring are applied. This project is aimed to assess the study risks of JCOG trials using the EORTC calculator. METHODS: We selected clinical trials open to patient recruitment in JCOG as of Nov 2014. Each trial was scored based on the EORTC study risk calculator and classified into three risk categories; low, medium and high. RESULTS: A total of 40 studies were included in the assessment. Twenty-seven studies (67.5%) were classified into low risk group, 12 (30%) in medium risk group, and only 1 (2.5%) in high risk group. Clinical trials evaluating multimodality therapy and/or using unapproved drugs tended to be scored higher and most of them were classified into medium or high risk group. CONCLUSIONS: JCOG conducts central monitoring and site visit audit with sampling source data verification for every trial, which are almost compatible with the way in EORTC for the medium risk group. Because most of the JCOG studies were classified into low or medium risk group, the intensity of monitoring and audit in JCOG was considered as reasonable even from the EORTC perspective.

Efficacy of aspirin for stage III colorectal cancer: a randomized double-blind placebo-controlled trial (JCOG1503C, EPISODE-III trial).

Adjuvant chemotherapy is the current standard treatment for stage III colorectal cancer after curative resection. However, the prognosis of stage III colorectal cancer is still poor even after curative resection and adjuvant chemotherapy. Several observational studies suggested that the anti-tumor effect of aspirin. Therefore, we planned a randomized double-blind placebo-controlled phase III trial, which commenced in Japan in March 2018, to confirm the superiority of aspirin over placebo added to adjuvant chemotherapy in terms of disease-free survival (DFS) for stage III colorectal cancer patients after curative resection. A total of 880 patients will be accrued from 20 Japanese institutions within 3 years. The primary endpoint is DFS and the secondary endpoints are overall survival, relapse-free survival, relative dose intensity, adverse events, and serious adverse events. This trial has been registered at Japan Registry of Clinical Trials as jRCTs031180009 (https://jrct.niph.go.jp/detail/589).

Role of the putative PKC phosphorylation sites of the type IIc sodium-dependent phosphate transporter in parathyroid hormone regulation.

BACKGROUND: Injection of parathyroid hormone (PTH) rapidly stimulates renal Pi excretion, in part by downregulating NaPi-IIa (Npt2a/SLC34A1) and NaPi-IIc (Npt2c/SLC34A3) transporters. The mechanisms underlying the effects of PTH on NaPi-IIc are not fully elucidated. METHODS: We analyzed the effect of PTH on inorganic phosphate (Pi) reabsorption in Npt2a-/- mice to eliminate the influence of Npt2a on renal Pi reabsorption. In opossum kidney (OK) cells and Xenopus oocytes, we investigated the effect of NaPi-IIc transporter phosphorylation. Studies of mice with mutations of NaPi-IIc protein in which serine and threonine were replaced with either alanine (A), which prevents phosphorylation, or aspartic acid (D), which mimics the charged state of phosphorylated NaPi-IIc, were also performed to evaluate the involvement of phosphorylation in the regulation of transport function. RESULTS: The Npt2a-/- experiments showed that PTH administration rapidly inactivated NaPi-IIc function in the apical membrane of proximal tubular cells. Analysis of mutant proteins (S71, S138, T151, S174, T583) at putative protein kinase C sites, revealed that S138 markedly suppressed the function and cellular expression of mouse NaPi-IIc in Xenopus oocytes and OK cells. In addition, 138D had a short half-life compared with wild-type protein. CONCLUSIONS: The present study suggests that acute regulation of NaPi-IIc protein by PTH is involved in the inactivation of Na+-dependent Pi cotransporter activity and that phosphorylation of the transporter is involved in the rapid modification.

Analysis of opossum kidney NaPi-IIc sodium-dependent phosphate transporter to understand Pi handling in human kidney.

BACKGROUND: The role of Na+-dependent inorganic phosphate (Pi) transporters in the human kidney is not fully clarified. Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is caused by loss-of-function mutations in the IIc Na+-dependent Pi transporter (NPT2c/Npt2c/NaPi-IIc) gene. Another Na+-dependent type II transporter, (NPT2A/Npt2a/NaPi-IIa), is also important for renal Pi reabsorption in humans. In mice, Npt2c deletion does not lead to hypophosphatemia and rickets because Npt2a compensates for the impaired Pi reabsorption. To clarify the differences between mouse and human, we investigated the relation between NaPi-IIa and NaPi-IIc functions in opossum kidney (OK) cells. METHODS: We cloned NaPi-IIc from OK cells and created opossum NaPi-IIc (oNaPi-IIc) antibodies. We used oNaPi-IIc small interference (si)RNA and investigated the role of NaPi-IIc in Pi transport in OK cells. RESULTS: We cloned opossum kidney NaPi-IIc cDNAs encoding 622 amino acid proteins (variant1) and examined their pH- and sodium-dependency. The antibodies reacted specifically with 75-kDa and 150-kDa protein bands, and the siRNA of NaPi-IIc markedly suppressed endogenous oNaPi-IIc in OK cells. Treatment with siRNA significantly suppressed the expression of NaPi-4 (NaPi-IIa) protein and mRNA. oNaPi-IIc siRNA also suppressed Na+/H+ exchanger regulatory factor 1 expression in OK cells. CONCLUSION: These findings suggest that NaPi-IIc is important for the expression of NaPi-IIa (NaPi-4) protein in OK cells. Suppression of Npt2c may downregulate Npt2a function in HHRH patients.

Precision medicine and novel molecular target therapies in acute myeloid leukemia: the background of hematologic malignancies (HM)-SCREEN-Japan 01.

The development of allogeneic hematopoietic-stem-cell transplantation has improved the prognosis of younger acute myeloid leukemia (AML) patients. However, the outcome of older AML patients remains poor. The majority of AML patients are elderly. For elderly AML patients unfit for intensive chemotherapy, less toxic single agent that targets a specific gene mutation or combination therapy with a single agent is needed. The role of chromosomal abnormalities and genetic mutations in leukemia has become more apparent, and detailed prognostic stratification based on the type of genetic mutation has been established. Next-generation sequencing (NGS) has been used for gene analysis of AML. In the future, the evaluation of biologically homogeneous population on the basis of chromosomal abnormalities and gene mutations will lead to a paradigm shift that will help in the development of optimized therapy. As rapid diagnosis of gene mutations is required by the clinical physicians to decide on induction therapy, it is important to have a swift turnaround time for comprehensive DNA sequencing to provide actionable data to clinical physicians. It is required to conduct a feasibility study to evaluate the turnaround time from sending the specimens to receiving the results while maintaining the quality of the specimens contributing to gene analysis. To detect infrequent gene mutations, investigators need to perform multicenter studies and/or cooperative-group trials with a certain sample size to examine the frequency of the gene mutations in elderly AML patients, enabling sufficient statistical power for meaningful comparisons.

[Vascular adverse events of ponatinib during treatment of Philadelphia chromosome-positive leukemia: a retrospective single-institution analysis].

Ponatinib (PON) is a key drug for patients with second tyrosine kinase inhibitor (TKI)-resistant/intolerant Philadelphia chromosome-positive leukemia (Ph+ leukemia); however, the occurrence of vascular adverse events (VAEs) in patients treated with PON should be carefully monitored. A retrospective analysis involving seven patients treated with PON was conducted to elucidate the incidence rate and risk factor for the development of VAEs. In the present study, risk assessment and monitoring of VAEs were performed using SCORE Risk Chart and Suita Score (10-year risk for fatal cardiovascular event), respectively. Despite the prophylactic use of aspirin, cerebral infarction and unstable angina occurred in two patients. By contrast, deep vein thrombosis did not improve in a patient treated with edoxaban. Our data suggest that patients with Ph+ leukemia possessing risk factors, medical history of lifestyle diseases, and administration of long-term second TKI treatment require careful monitoring of VAEs and therapeutic intervention to lifestyle diseases.

[Hairy cell leukemia complicated by bone marrow necrosis following cladribine administration].

Classic hairy cell leukemia (classic HCL) is a rare disease associated with indolent mature B-cell lymphoma. A 50-year-old man presented with pancytopenia for 3 years and was diagnosed with classic HCL because his lymphoid cells showed a hairy morphology with oval nuclei and indistinct nucleoli both in the peripheral blood and bone marrow (BM) smears. Flow cytometric analysis revealed that these cells expressed CD11c, CD25, and CD103, and the Sanger sequence method detected BRAF V600E mutation. Cladribine (0.09 mg/kg/day) was initiated for 7 days via continuous intravenous injection. On day 13, the patient died from bloodstream infection caused by methicillin-resistant Staphylococcus epidermidis. Autopsy findings revealed BM necrosis without residual leukemia cells caused by classic HCL, severe infection, and agents, such as cladribine and granulocyte-colony stimulating factor; however, its cause remained undetermined. Both early diagnosis and immediate clinical intervention are required to improve the clinical outcomes in classic HCL. The cause of hematopoiesis disturbance should also be identified using BM biopsy or magnetic resonance imaging before initiating treatment in classic HCL with severe pancytopenia.

Bortezomib plus dexamethasone vs thalidomide plus dexamethasone for relapsed or refractory multiple myeloma.

A randomized phase II selection design study (JCOG0904) was carried out to evaluate the more promising regimen between bortezomib (Bor) plus dexamethasone (Dex; BD) and thalidomide (Thal) plus Dex (TD) in Bor and Thal-naïve patients with relapsed or refractory multiple myeloma (RRMM). Patients ≥20 and <80 years old with a documented diagnosis of symptomatic multiple myeloma (MM) who received one or more prior therapies were randomized to receive BD (Bor 1.3 mg/m2 ) or TD (Thal 200 mg/d). In both arms, 8 cycles of induction (3-week cycle) were followed by maintenance phase (5-week cycle) until disease progression, unacceptable toxicity, or patient refusal. The primary end-point was 1-year progression-free survival (PFS). Forty-four patients were randomized and assigned to receive BD and TD (n = 22, each group). At a median follow-up of 34.3 months, the 1-year PFS in the BD and TD arms were 45.5% (95% confidence interval (CI), 24.4%-64.3%) and 31.8% (95% CI, 14.2%-51.1%), respectively, and the overall response rates were 77.3% and 40.9%, respectively. The 3-year overall survival (OS) was 70.0% (95% CI, 44.9%-85.4%) in the BD, and 48.8% (95% CI, 25.1%-69.0%) in the TD arm. Among grade 3/4 adverse events, thrombocytopenia (54.5% vs 0.0%) and sensory peripheral neuropathy (22.7% vs 9.1%) were more frequent in BD when compared with the TD arm. Patients treated with BD had better outcomes than those treated with TD with regard to 1-year PFS and 3-year OS. Thus, BD was prioritized over TD for further investigations in Bor and Thal-naïve RRMM patients. (Clinical trial registration no. UMIN000003135.).

The sodium phosphate cotransporter family and nicotinamide phosphoribosyltransferase contribute to the daily oscillation of plasma inorganic phosphate concentration.

Circulating inorganic phosphate exhibits a remarkable daily oscillation based on food intake. In humans and rodents, the daily oscillation in response to food intake may be coordinated to control the intestinal absorption, renal excretion, cellular shifts, and extracellular concentration of inorganic phosphate. However, mechanisms regulating the resulting oscillation are unknown. Here we investigated the roles of the sodium phosphate cotransporter SLC34 (Npt2) family and nicotinamide phosphoribosyltransferase (Nampt) in the daily oscillation of plasma inorganic phosphate levels. First, it is roughly linked to urinary inorganic phosphate excretion. Second, expression of renal Npt2a and Npt2c, and intestinal Npt2b proteins also exhibit a dynamic daily oscillation. Analyses of Npt2a, Npt2b, and Npt2c knockout mice revealed the importance of renal inorganic phosphate reabsorption and cellular inorganic phosphate shifts in the daily oscillation. Third, experiments in which nicotinamide and a specific Nampt inhibitor (FK866) were administered in the active and rest phases revealed that the Nampt/NAD+ system is involved in renal inorganic phosphate excretion. Additionally, for cellular shifts, liver-specific Nampt deletion disturbed the daily oscillation of plasma phosphate during the rest but not the active phase. In systemic Nampt+/- mice, NAD levels were significantly reduced in the liver, kidney, and intestine, and the daily oscillation (active and rest phases) of the plasma phosphate concentration was attenuated. Thus, the Nampt/NAD+ system for Npt2 regulation and cellular shifts to tissues such as the liver play an important role in generating daily oscillation of plasma inorganic phosphate levels.

A Phase III trial of a single early intravesical instillation of pirarubicin to prevent bladder recurrence after radical nephroureterectomy for upper tract urothelial carcinoma (JCOG1403, UTUC THP Phase III).

Observation is the current standard for managing cases of Stage 0a-III upper tract urothelial carcinoma after radical nephroureterectomy. A randomized Phase III trial commenced in Japan during October 2016. The trial is designed to investigate the superiority of a single early intravesical instillation of pirarubicin, compared with observation, in terms of relapse-free survival after radical nephroureterectomy for Stage 0a-III upper tract urothelial carcinoma. During a 5-year period, 310 patients will be recruited from 43 Japanese institutions. The primary endpoint is defined as relapse-free survival, and the secondary endpoints are overall survival, intravesical relapse-free survival, adverse events, and serious adverse events. This trial has been registered in the UMIN Clinical Trials Registry (UMIN000024267, http://www.umin.ac.jp/ctr/index.htm).