MBTD1 preserves adult hematopoietic stem cell pool size and function.

Mbtd1 (mbt domain containing 1) encodes a nuclear protein containing a zinc finger domain and four malignant brain tumor (MBT) repeats. We previously generated Mbtd1-deficient mice and found that MBTD1 is highly expressed in fetal hematopoietic stem cells (HSCs) and sustains the number and function of fetal HSCs. However, since Mbtd1-deficient mice die soon after birth possibly due to skeletal abnormalities, its role in adult hematopoiesis remains unclear. To address this issue, we generated Mbtd1 conditional knockout mice and analyzed adult hematopoietic tissues deficient in Mbtd1. We observed that the numbers of HSCs and progenitors increased and Mbtd1-deficient HSCs exhibited hyperactive cell cycle, resulting in a defective response to exogenous stresses. Mechanistically, we found that MBTD1 directly binds to the promoter region of FoxO3a, encoding a forkhead protein essential for HSC quiescence, and interacts with components of TIP60 chromatin remodeling complex and other proteins involved in HSC and other stem cell functions. Restoration of FOXO3a activity in Mbtd1-deficient HSCs in vivo rescued cell cycle and pool size abnormalities. These findings indicate that MBTD1 is a critical regulator for HSC pool size and function, mainly through the maintenance of cell cycle quiescence by FOXO3a.

UTX maintains the functional integrity of the murine hematopoietic system by globally regulating aging-associated genes.

Epigenetic regulation is essential for the maintenance of the hematopoietic system, and its deregulation is implicated in hematopoietic disorders. In this study, UTX, a demethylase for lysine 27 on histone H3 (H3K27) and a component of COMPASS-like and SWI/SNF complexes, played an essential role in the hematopoietic system by globally regulating aging-associated genes. Utx-deficient (UtxΔ/Δ) mice exhibited myeloid skewing with dysplasia, extramedullary hematopoiesis, impaired hematopoietic reconstituting ability, and increased susceptibility to leukemia, which are the hallmarks of hematopoietic aging. RNA-sequencing (RNA-seq) analysis revealed that Utx deficiency converted the gene expression profiles of young hematopoietic stem-progenitor cells (HSPCs) to those of aged HSPCs. Utx expression in hematopoietic stem cells declined with age, and UtxΔ/Δ HSPCs exhibited increased expression of an aging-associated marker, accumulation of reactive oxygen species, and impaired repair of DNA double-strand breaks. Pathway and chromatin immunoprecipitation analyses coupled with RNA-seq data indicated that UTX contributed to hematopoietic homeostasis mainly by maintaining the expression of genes downregulated with aging via demethylase-dependent and -independent epigenetic programming. Of note, comparison of pathway changes in UtxΔ/Δ HSPCs, aged muscle stem cells, aged fibroblasts, and aged induced neurons showed substantial overlap, strongly suggesting common aging mechanisms among different tissue stem cells.

[A Case of Resection of Locally Advanced Ascending Colon Cancer in an Elderly Patient with Parkinson's Disease].

The case presented here is of a man in his 80s who was attending the Department of Neurology for Parkinson's disease. He had a fever and visited the emergency department. A CT scan revealed a 10 cm mass in the hepatic flexure that was suspected of invading the duodenum, as well as numerous enlarged lymph nodes around the mass. A colonoscopy revealed a semi-peripheral type 3 tumor, and a biopsy showed adenocarcinoma(tub1-tub2). A right hemicolectomy was performed, and the tumor was located in the hepatic flexure of the ascending colon and was found to be in a mass with lymph nodes and adhesions to the duodenum. Due to the invasiveness of the surgery and the decrease in ADL, the patient's postoperative course required prolonged hospitalization. He was transferred to the hospital at POD33 and discharged at POD64. Due to his old age, adjuvant chemotherapy was not administered, and he is still alive 1 year after surgery with no recurrence. Even though his hospital stay was prolonged due to his decreased ADL, he is now able to return home. Aggressive resection may provide good results even in elderly patients.

[Eight Cases of Breast Cancer That Relapsed More Than Ten Years after Initial Treatment].

Recurrence is more common for breast cancer than other solid tumors. In the last 5 years, we experienced 8 cases that relapsed more than 10 years after initial treatment. All cases were hormone-sensitive and HER2-negative. The Ki-67 percentage score was less than 15% in 7 cases. The age range at recurrence was 56-93 years(mean, 74.6 years), and the time to recurrence was 10-14 years and 20 or more years in 6 and 2 cases(mean, 14.6 years), respectively. The triggers for diagnosis were subjective symptoms, follow-up, and examination for other diseases in 3, 3, and 2 cases, respectively. The recurrence sites included the axilla, pleura/lung, liver/lung, skin, and chest wall in 3, 2, 1, 1, and 1 case, respectively. Treatment included an aromatase inhibitor(AI)and AI plus CDK4/6 inhibitor in 5 and 3 cases, respectively. The post-recurrence treatment period was 6-31 months(mean, 21.6 months), with 4 cases of PR, 3 cases of SD, and 1 case of death from other disease. There were 3 cases of axillary recurrence and 1 case each of neuropathic pain, upper limb edema, and local pain; all were alleviated by the treatment. In 2 cases, the pleural effusion decreased without chest tube drainage. Hormone receptor- positive late-relapse cases are generally highly therapeutically sensitive with favorable prognosis. In many cases, AI alone was selected considering patient age, side effects, treatment costs, and other factors.

[A Case in Which Inferior Vena Cava Stent Placement Was Effective for Inferior Vena Cava Stenosis Due to Metastatic Liver Tumor].

A 60s woman was diagnosed with cecal cancer with multiple liver metastases(final pathology was T4aN1M1[H1])and underwent ileocecal resection and D3 dissection. She did not wish for postoperative chemotherapy and surgical treatment of liver metastases. One and a half years after surgery, she developed extremity edema of lower legs and hypoalbuminemia, and she gained 20 kg. Contrast-enhanced CT showed stenosis of the inferior vena cava due to liver metastases, which was markedly improved the symptoms by placement of an inferior vena cava stent. Inferior vena cava stent placement is a minimally invasive treatment and can be an option as it can be expected to improve quality of life in some cases.

Mule/Huwe1/Arf-BP1 suppresses Ras-driven tumorigenesis by preventing c-Myc/Miz1-mediated down-regulation of p21 and p15.

Tumorigenesis results from dysregulation of oncogenes and tumor suppressors that influence cellular proliferation, differentiation, apoptosis, and/or senescence. Many gene products involved in these processes are substrates of the E3 ubiquitin ligase Mule/Huwe1/Arf-BP1 (Mule), but whether Mule acts as an oncogene or tumor suppressor in vivo remains controversial. We generated K14Cre;Mule(flox/flox(y)) (Mule kKO) mice and subjected them to DMBA/PMA-induced skin carcinogenesis, which depends on oncogenic Ras signaling. Mule deficiency resulted in increased penetrance, number, and severity of skin tumors, which could be reversed by concomitant genetic knockout of c-Myc but not by knockout of p53 or p19Arf. Notably, in the absence of Mule, c-Myc/Miz1 transcriptional complexes accumulated, and levels of p21CDKN1A (p21) and p15INK4B (p15) were down-regulated. In vitro, Mule-deficient primary keratinocytes exhibited increased proliferation that could be reversed by Miz1 knockdown. Transfer of Mule-deficient transformed cells to nude mice resulted in enhanced tumor growth that again could be abrogated by Miz1 knockdown. Our data demonstrate in vivo that Mule suppresses Ras-mediated tumorigenesis by preventing an accumulation of c-Myc/Miz1 complexes that mediates p21 and p15 down-regulation.

[Rapid Recurrence of Dedifferentiated Liposarcoma of Occult Primary in the Abdomen-A Case Report].

A man in his 70s was referred to our hospital for the examination of an abdominal tumor detected incidentally. The tumor was resected with a preoperative diagnosis of gastric submucosal tumor. As a result of the histopathological examination, dedifferentiated liposarcoma was diagnosed. The tumor recurred 2 months after the operation, and resection was attempted again. However, the intraoperative findings showed multiple metastatic lesions, and radical resection was considered impossible. Chemotherapy was therefore administered with doxorubicin monotherapy and eribulin, but the tumor rapidly increased, and the patient ultimately died 8 months after the initial operation. Dedifferentiated liposarcoma is a histologic type with a poor prognosis among liposarcoma. Resection is the standard treatment, but it frequently develops in the retroperitoneum, and it is often found in an advanced state due to the lack of subjective symptoms compared to lesions of the extremities. In addition, its tendency to infiltrate into the surrounding area and to metastasize are also factors that make radical resection difficult. We herein report a case of dedifferentiated liposarcoma that was detected asymptomatically but had a rapid outcome.

Rate of Reoperation Decreased Significantly After Year 2002 in Patients With Crohn's Disease.

BACKGROUND & AIMS: Patients with Crohn's disease (CD) can require multiple intestinal surgeries. We examined time trends and risk factors for reoperation in patients with CD who underwent intestinal surgery, focusing on the effects of postoperative medical treatments. METHODS: We performed a retrospective analysis of 1871 patients with CD who underwent initial intestinal resection at 10 tertiary care institutions in Japan, with an initial surgical date after May 1982. We collected data on the background characteristics of all patients, including Montreal Classification, smoking status, and medical therapy after surgery (tumor necrosis factor antagonists [anti-TNF] agents or immunomodulators). The primary outcome was requirement for first reoperation. Rate of reoperation was estimated using the Kaplan-Meier method, and risk factors for reoperation were identified using the Cox regression model. RESULTS: The overall cumulative 5- and 10-year reoperation rates were 23.4% and 48.0%, respectively. Multivariable analysis showed that patients who underwent the initial surgery after May 2002 had a significantly lower rate of reoperation than patients who underwent surgery before April 2002 (hazard ratio [HR], 0.72; 95% CI, 0.61-0.86). Preoperative smoking (HR, 1.40; 95% CI, 1.18-1.68), perianal disease (HR, 1.50; 95% CI, 1.27-1.77), and ileocolic type of CD (HR, 1.42; 95% CI, 1.20-1.69) were significant risk factors for reoperation. Postoperative use of immunomodulators (HR, 0.60; 95% CI, 0.44-0.81) and anti-TNF therapy (HR, 0.71; 95% CI, 0.57-0.88) significantly reduced the risk. Anti-TNF was effective in the bionaive subgroup. CONCLUSIONS: The rate of reoperation in patients with CD significantly decreased after May 2002. Postoperative use of anti-TNF agents might reduce the reoperation rate for bionaive patients with CD.

D-2-hydroxyglutarate produced by mutant IDH1 perturbs collagen maturation and basement membrane function.

Isocitrate dehydrogenase-1 (IDH1) R132 mutations occur in glioma, but their physiological significance is unknown. Here we describe the generation and characterization of brain-specific Idh1 R132H conditional knock-in (KI) mice. Idh1 mutation results in hemorrhage and perinatal lethality. Surprisingly, intracellular reactive oxygen species (ROS) are attenuated in Idh1-KI brain cells despite an apparent increase in the NADP(+)/NADPH ratio. Idh1-KI cells also show high levels of D-2-hydroxyglutarate (D2HG) that are associated with inhibited prolyl-hydroxylation of hypoxia-inducible transcription factor-1α (Hif1α) and up-regulated Hif1α target gene transcription. Intriguingly, D2HG also blocks prolyl-hydroxylation of collagen, causing a defect in collagen protein maturation. An endoplasmic reticulum (ER) stress response induced by the accumulation of immature collagens may account for the embryonic lethality of these mutants. Importantly, D2HG-mediated impairment of collagen maturation also led to basement membrane (BM) aberrations that could play a part in glioma progression. Our study presents strong in vivo evidence that the D2HG produced by the mutant Idh1 enzyme is responsible for the above effects.

[Mastectomy Followed by Skin-Transplantation Restored QOL and Enabled Chemotherapy in Two Cases of Locally Advanced Breast Cancer with Uncontrollable Bleeding].

Here, we report 2 cases of locally advanced breast cancer with uncontrollable bleeding treated with mastectomy followed by skin transplantation. The operation restored the QOL and enabled chemotherapy in postoperative periods. Case 1: A woman in her 70s was brought by an ambulance because of heart failure symptoms. She had a huge breast tumor on her left chest wall that bled repeatedly, necessitating frequent blood transfusions. An operation was performed, and chemotherapy was provided until she died of brain metastasis 1 year and 8 months after surgery. Case 2: A woman in her 70s was urgently hospitalized with a lumbar vertebrae bone fracture. She had a huge breast tumor on her right chest wall that bled repeatedly. Blood examination revealed severe anemia. An operation was performed, and chemotherapy was introduced sequentially. She is alive with a good status 2 years and 1 month after surgery.

Surveillance Colonoscopy for Ulcerative Colitis-Associated Colorectal Cancer Offers Better Overall Survival in Real-World Surgically Resected Cases.

OBJECTIVES: To determine the effectiveness of surveillance colonoscopy (SC) and optimize its use by assessing real-world surgically resected cases of ulcerative colitis (UC)-associated colorectal cancer (CRC) and dysplasia. METHODS: Clinicopathological data of 406 (238 CRC and 168 dysplasia) patients who underwent surgical resection in 10 UC specialized institutions were retrospectively reviewed. The overall survival (OS) rates were compared between the SC and non-SC groups. The incidence of and risk factors for early-onset CRC (<8 years after UC onset) were identified. The distribution of CRC lesions was also assessed. RESULTS: Cancer stages were significantly more advanced in the non-SC group than in the SC group (P < 0.001). The patients in the SC group showed significantly better OS than those in the non-SC group (5-year OS: 89% vs 70%; log-rank test: P = 0.001). Seventeen percent of patients developed CRC within 8 years after UC onset. The age at UC onset was a risk factor and a good predictor of early-onset CRC (<8 years) (P < 0.01; AUC: 0.85). The most common sites of CRC were the rectum (51%) and sigmoid colon (20%). Multiple CRC was identified in 16% of patients. CONCLUSIONS: Surveillance colonoscopy was effective and improved the OS in patients with UC. We recommend that patients with late-onset UC (>40 years) undergo SCs earlier because of the high incidence of CRC within 8 years of UC onset. Moreover, the rectum and sigmoid colon should be more thoroughly examined.

JMJD2B/KDM4B inactivation in adipose tissues accelerates obesity and systemic metabolic abnormalities.

Obesity is a serious global health issue; however, the roles of genetics and epigenetics in the onset and progression of obesity are still not completely understood. The aim of this study was to determine the role of Kdm4b, which belongs to a subfamily of histone demethylases, in adipogenesis and fat metabolism in vivo. We established conditional Kdm4b knockout mice. Inactivation of Kdm4b in adipocytes (K4bKO) induced profound obesity in mice on a high fat diet (HFD). The HFD-fed K4bKO mice exhibited an increased volume of fat mass and higher expression levels of adipogenesis-related genes. In contrast, the genes involved in energy expenditure and mitochondrial functions were down-regulated. Supporting these findings, the energy expenditure of Kdm4b-deficient cells was markedly decreased. In addition, progression of glucose intolerance and hepatic steatosis with hepatocellular damages was observed. These data indicate that Kdm4b is a critical regulator of systemic metabolism via enhancing energy expenditure in adipocytes.

Acquired expression of CblQ367P in mice induces dysplastic myelopoiesis mimicking chronic myelomonocytic leukemia.

Chronic myelomonocytic leukemia (CMML) is a hematological malignancy characterized by uncontrolled proliferation of dysplastic myelomonocytes and frequent progression to acute myeloid leukemia (AML). We identified mutations in the Cbl gene, which encodes a negative regulator of cytokine signaling, in a subset of CMML patients. To investigate the contribution of mutant Cbl in CMML pathogenesis, we generated conditional knockin mice for Cbl that express wild-type Cbl in a steady state and inducibly express CblQ367P , a CMML-associated Cbl mutant. CblQ367P mice exhibited sustained proliferation of myelomonocytes, multilineage dysplasia, and splenomegaly, which are the hallmarks of CMML. The phosphatidylinositol 3-kinase (PI3K)-AKT and JAK-STAT pathways were constitutively activated in CblQ367P hematopoietic stem cells, which promoted cell cycle progression and enhanced chemokine-chemokine receptor activity. Gem, a gene encoding a GTPase that is upregulated by CblQ367P , enhanced hematopoietic stem cell activity and induced myeloid cell proliferation. In addition, Evi1, a gene encoding a transcription factor, was found to cooperate with CblQ367P and progress CMML to AML. Furthermore, targeted inhibition for the PI3K-AKT and JAK-STAT pathways efficiently suppressed the proliferative activity of CblQ367P -bearing CMML cells. Our findings provide insights into the molecular mechanisms underlying mutant Cbl-induced CMML and propose a possible molecular targeting therapy for mutant Cbl-carrying CMML patients.

Propagation of trimethylated H3K27 regulated by polycomb protein EED is required for embryogenesis, hematopoietic maintenance, and tumor suppression.

Polycomb repressive complex 2 (PRC2) catalyzes the monomethylation, dimethylation, and trimethylation of histone H3 Lys27 (H3K27) and acts as a central epigenetic regulator that marks the repressive chromatin domain. Embryonic ectoderm development (EED), an essential component of PRC2, interacts with trimethylated H3K27 (H3K27me3) through the aromatic cage structure composed of its three aromatic amino acids, Phe97, Trp364, and Tyr365. This interaction allosterically activates the histone methyltransferase activity of PRC2 and thereby propagates repressive histone marks. In this study, we report the analysis of knock-in mice harboring the myeloid disorder-associated EED Ile363Met (I363M) mutation, analogous to the EED aromatic cage mutants. The I363M homozygotes displayed a remarkable and preferential reduction of H3K27me3 and died at midgestation. The heterozygotes increased the clonogenic capacity and bone marrow repopulating activity of hematopoietic stem/progenitor cells (HSPCs) and were susceptible to leukemia. Lgals3, a PRC2 target gene encoding a multifunctional galactose-binding lectin, was derepressed in I363M heterozygotes, which enhanced the stemness of HSPCs. Thus, our work provides in vivo evidence that the structural integrity of EED to H3K27me3 propagation is critical, especially for embryonic development and hematopoietic homeostasis, and that its perturbation increases the predisposition to hematologic malignancies.

[A Case of Gastrointestinal Perforation in Gastric Cancer during Chemotherapy with Paclitaxel plus Ramucirumab].

A 54-year-old man underwent distal gastrectomy with D2 lymph node dissection in our institution in March 2017 due to the presence of advanced gastric cancer. The pathological diagnosis was signet ring, poorly differentiated, and moderate differentiated adenocarcinoma, which was pT4aN3aM0, pStage Ⅲc and HER2-negative. After surgery, he received adjuvant chemotherapy with S-1, however, he was diagnosed with dissemination and lymph node recurrence in June. Tumor marker, CEA level decreased after the introduction of the next treatment(capecitabine plus cisplatin), however the tumor marker level rose again in September, and the chemotherapy regimen was changed to weekly paclitaxel(PTX). Furthermore, ramucirumab was added to the weekly PTX regime in January 2018, as the tumor marker level rose again. One week after the last ramucirumab administration he visited our hospital with abdominal pain, and emergency surgery was performed after the diagnosis of a gastrointestinal perforation using CT. The surgery revealed dirty fluid and countless dissemination nodes throughout the abdominal cavity, and a small intestinal perforation on a white dissemination node was identified 70 cm proximal to the end of the ileum. We performed small bowel segmental resection and functional end-to-end anastomosis. No complications were observed, and an oral diet was able to be started after surgery; however, he was introduced to the best supportive care(BSC)as his general condition gradually deteriorated.

[Curative Resection of Locally Advanced Rectal Cancer with Synchronous Liver Metastasis after Long-Term Chemotherapy].

A 60s man was diagnosed with unresectable advanced rectal cancer with synchronous solitary liver metastasis. Chemotherapy was administered and the primary tumor shrank immediately. However, he still demonstrated dorsal extension; therefore, chemotherapy was continued for approximately 1 year. After long-term chemotherapy, the primary tumor was deemed to be resectable because the dorsal extension had decreased. We achieved curative resection by performing a primary tumor and liver resection and he has shown no recurrence without adjuvant chemotherapy. Although the primary tumor was initially diagnosed as unresectable, it is important to consider the potential for curative resection after long-term chemotherapy.

Effect of the "Building Osteo Neatly Exercise" program on quantitative ultrasound parameters and plantar pressure distribution for college-aged females.

[Purpose] We investigated the effects of a specifically designed exercise program that focused on the arches of the foot and the forefoot (the "Building Osteo Neatly Exercise" program) in college-aged females. [Participants and Methods] Forty college-aged females were divided randomly into experimental and control groups. The experimental group underwent the Building Osteo Neatly Exercise program for 60 min once a week for 4 months. In both groups, the plantar pressure distribution and quantitative ultrasound parameters of the calcaneus (speed of sound and bone area ratio) were evaluated at the beginning and end of the study. The plantar pressure distribution during walking was measured using a pressure plate to evaluate the deviation from the ideal values for the following: contact time, contact duration, peak pressure time, and foot pressure, all measured in the rear foot (the external and internal sides), medial forefoot including (the hallux and second and third toes), and lateral forefoot (the fourth and fifth toes). [Results] After completing the program, the speed of sound and bone area ratio had increased significantly in the experimental group and were significantly higher than those in the control group. The experimental group showed significant improvements in the deviations from the ideal values in contact time and contact duration in the medial forefoot, all four parameters in the lateral forefoot, and pressure in the rear foot. [Conclusion] College-aged females who participated in the Building Osteo Neatly Exercise program once weekly for 4 months exhibited significant improvements in bone strength in the calcaneus and in foot function, as shown by the plantar pressure distribution. Further studies are needed to examine the outcomes of the Building Osteo Neatly Exercise program in an elderly population.

Nivolumab versus Everolimus in Advanced Renal-Cell Carcinoma.

BACKGROUND: Nivolumab, a programmed death 1 (PD-1) checkpoint inhibitor, was associated with encouraging overall survival in uncontrolled studies involving previously treated patients with advanced renal-cell carcinoma. This randomized, open-label, phase 3 study compared nivolumab with everolimus in patients with renal-cell carcinoma who had received previous treatment. METHODS: A total of 821 patients with advanced clear-cell renal-cell carcinoma for which they had received previous treatment with one or two regimens of antiangiogenic therapy were randomly assigned (in a 1:1 ratio) to receive 3 mg of nivolumab per kilogram of body weight intravenously every 2 weeks or a 10-mg everolimus tablet orally once daily. The primary end point was overall survival. The secondary end points included the objective response rate and safety. RESULTS: The median overall survival was 25.0 months (95% confidence interval [CI], 21.8 to not estimable) with nivolumab and 19.6 months (95% CI, 17.6 to 23.1) with everolimus. The hazard ratio for death with nivolumab versus everolimus was 0.73 (98.5% CI, 0.57 to 0.93; P=0.002), which met the prespecified criterion for superiority (P≤0.0148). The objective response rate was greater with nivolumab than with everolimus (25% vs. 5%; odds ratio, 5.98 [95% CI, 3.68 to 9.72]; P<0.001). The median progression-free survival was 4.6 months (95% CI, 3.7 to 5.4) with nivolumab and 4.4 months (95% CI, 3.7 to 5.5) with everolimus (hazard ratio, 0.88; 95% CI, 0.75 to 1.03; P=0.11). Grade 3 or 4 treatment-related adverse events occurred in 19% of the patients receiving nivolumab and in 37% of the patients receiving everolimus; the most common event with nivolumab was fatigue (in 2% of the patients), and the most common event with everolimus was anemia (in 8%). CONCLUSIONS: Among patients with previously treated advanced renal-cell carcinoma, overall survival was longer and fewer grade 3 or 4 adverse events occurred with nivolumab than with everolimus. (Funded by Bristol-Myers Squibb; CheckMate 025 ClinicalTrials.gov number, NCT01668784.).

[Curative Resection of Locally Advanced Rectal Cancer with Para-Aortic Lymph Node Swelling after Long-Term Chemotherapy].

A 60s man was diagnosed as having unresectable advanced rectal cancer with swelling of the para-aortic lymph nodes. Chemotherapy was administered, and the primary tumor immediately shrank. He still had para-aortic lymph node swelling; therefore, chemotherapy was continued for approximately 2 years. After long-term chemotherapy, we diagnosed his tumor as resectable because the para-aortic lymph node swelling had shrunk. We achieved curative resection, and he has shown no recurrence without adjuvant chemotherapy. Although chemotherapy is the main treatment for unresectable advanced colorectalcancer, it is important to consider curative resection, as in this case with long-term chemotherapy.