Synergistic antitumor activity by dual blockade of CCR1 and CXCR2 expressed on myeloid cells within the tumor microenvironment.

BACKGROUND: Chemokine signaling within the tumor microenvironment can promote tumor progression. Although CCR1 and CXCR2 on myeloid cells could be involved in tumor progression, it remains elusive what effect would be observed if both of those are blocked. METHODS: We employed two syngeneic colorectal cancer mouse models: a transplanted tumor model and a liver metastasis model. We generated double-knockout mice for CCR1 and CXCR2, and performed bone marrow (BM) transfer experiments in which sub-lethally irradiated wild-type mice were reconstituted with BM from either wild-type, Ccr1-/-, Cxcr2-/- or Ccr1-/-Cxcr2-/- mice. RESULTS: Myeloid cells that express MMP2, MMP9 and VEGF were accumulated around both types of tumors through CCR1- and CXCR2-mediated pathways. Mice reconstituted with Ccr1-/-Cxcr2-/- BM exhibited the strongest suppression of tumor growth and liver metastasis compared with other three groups. Depletion of CCR1+CXCR2+ myeloid cells led to a higher frequency of CD8+ T cells, whereas the numbers of Ly6G+ neutrophils, FOXP3+ Treg cells and CD31+ endothelial cells were significantly decreased. Furthermore, treatment with a neutralizing anti-CCR1 mAb to mice reconstituted with Cxcr2-/- BM significantly suppressed tumor growth and liver metastasis. CONCLUSION: Dual blockade of CCR1 and CXCR2 pathways in myeloid cells could be an effective therapy against colorectal cancer.

Mirtazapine plus granisetron and dexamethasone for carboplatin-induced nausea and vomiting in patients with thoracic cancers: A prospective multicenter phase II trial.

BACKGROUND: Mirtazapine blocks 5-hydroxytryptamine type (5-HT)2A, 5-HT2C, 5-HT3 and histamine H1 receptors, similarly to olanzapine. This study aimed to investigate the efficacy and safety of mirtazapine plus granisetron and dexamethasone for carboplatin (CBDCA)-induced nausea and vomiting in patients with thoracic cancers. METHODS: We conducted a prospective, open-label, single-arm, multicenter, phase II trial in four institutions in Japan. Registered patients were moderately to highly emetogenic chemotherapy-naïve, and were scheduled to receive CBDCA at area under the curve (AUC) ≥ 4 mg/mL per minute. Patients received mirtazapine 15 mg/day orally at bedtime for four consecutive days, in combination with granisetron and dexamethasone. Primary endpoint was complete response (CR; no emesis and no use of rescue medication) rate during the delayed period (24-120 h). RESULTS: Between July 2022 and July 2023, 52 patients were enrolled, and 48 patients were evaluated. CR rates in the delayed (24-120 h), overall (0-120 h), and acute periods (0-24 h) were 83.3%, 83.3%, and 100%, respectively. No grade 3 or higher treatment-related adverse events were observed except for one patient who had grade 3 dry mouth as evaluated by Common Terminology Criteria for Adverse Events version 5.0. CONCLUSIONS: Prophylactic antiemetic therapy with mirtazapine plus granisetron and dexamethasone shows promising efficacy and an acceptable safety profile. This three-drug combination appears to be a reasonable treatment approach in patients with thoracic cancers receiving a CBDCA-based regimen at AUC ≥ 4 mg/mL per minute.

Downregulation of osteoprotegerin in colorectal cancer cells promotes liver metastasis via activating tumor-associated macrophage.

Osteoprotegerin (OPG) is a secreted cytokine that functions as a decoy receptor for receptor activator of nuclear factor kappa-B (RANK) ligand (RANKL). Anti-RANKL treatment for bone metastasis has been widely accepted for solid tumors. However, the mechanism of OPG-RANKL-RANK signaling in systemic colorectal cancer (CRC) metastasis remains unclear. In this study, we investigated the relevance and function of OPG expression in CRC liver metastasis. First, we performed in silico analysis using The Cancer Genome Atlas public database and found that lower OPG expression in CRC was associated with poor overall survival. Immunohistochemistry analyses using resected specimen from patients with CRC in our institute confirmed the result. Patient-matched primary CRC and liver metastases showed a significant downregulation of OPG expression in metastatic lesions. In CRC cell lines, OPG expression did not suppress cell proliferation and migration. However, OPG expression inhibited macrophage migration by suppressing the RANKL-RANK pathway. Moreover, in vivo mouse liver metastasis models showed that OPG expression in CRC cells suppressed liver metastases. In addition, treatment with an anti-RANKL neutralizing antibody also suppressed liver metastases. These results showed that downregulation of OPG expression in CRC cells promotes liver metastasis by activating tumor-associated macrophage, which can become a candidate for targeted therapy with anti-RANKL neutralizing antibody for CRC liver metastasis.

Neutrophil Extracellular Traps Promote Metastases of Colorectal Cancers through Activation of ERK Signaling by Releasing Neutrophil Elastase.

Neutrophil extracellular traps (NETs) play important roles in host immunity, as there is increasing evidence of their contribution to the progression of several types of cancers even though their role in colorectal cancers (CRCs) remains unclear. To investigate the clinical relevance of NETs in CRCs, we examined the expression of citrullinated histone H3 using immunohistochemistry and preoperative serum myeloperoxidase-DNA complexes in CRC patients using an enzyme-linked immunosorbent assay. High expression of intratumoral or systemic NETs was found to correlate with poor relapse-free survival (RFS), for which it is an independent prognostic factor. In vitro investigations of CRC cells (HCT116, HT29) revealed that NETs did not affect their proliferation but did promote the migration of CRC cells mediated by neutrophil elastase (NE) released during NETosis to increase extracellular signal-regulated kinase (ERK) activity. In vivo experiments using nude mice (KSN/slc) revealed that NE inhibition suppressed liver metastases in CRC cells, although it did not affect the growth of subcutaneously implanted tumors. Taken together, these results suggest that NET formation correlates with poor prognoses of patients with CRC and that the inhibition of NE could be a potential therapy for CRC metastases.

The impact of preclinical clerkship in general surgery on medical students' attitude to a surgical career.

PURPOSE: With the advent of a new program for postgraduate medical students in 2004, the number of applicants choosing surgical careers in Japan has been declining. We conducted this study to evaluate the impact of preclinical clerkship and how it affects students' attitudes toward a surgical career. METHODS: The subjects of our study were fifth-year medical students who participated in a clinical clerkship in general surgery in our department between April 2021 and March 2022. We conducted pre- and post-preclinical clerkship surveys to assess the perceived image of surgeons and the impact of clerkship on surgical career interest. RESULTS: Among 132 medical students (77 men and 55 women) who rotated through preclinical clerkship in our department, 125 participated in the survey and 66% expressed interest in a surgical career. In the post-clerkship survey, an increased interest in a surgical career was expressed by 79% of the students; notably, including those who initially expressed interest. Approximately 77% of students were satisfied with the practical skill training they received. CONCLUSION: Engaging medical students early in surgical experience through a preclinical clerkship for general surgery appears to promote their interest in a surgical career.

Efficacy of side-to-end anastomosis to prevent anastomotic leakage after anterior resection for rectal cancer.

The present study aimed to investigate whether side-to-end anastomosis could provide an improved surgical outcome, such as lower anastomotic leakage rate, compared with end-to-end anastomosis, following anterior resection for rectal and rectosigmoid cancer. This retrospective study included 162 patients with rectal cancer who underwent elective anterior resection between January 2012 and October 2019 at a single institution. Patients with double cancers or colonic J-pouch were excluded. Anastomotic leakage was defined clinically and radiologically. Side-to-end anastomosis was introduced in the International University of Health and Welfare Mita Hospital in January 2017. Side-to-end anastomosis was performed in 63 patients, while end-to-end anastomosis was performed in 99 patients. Tumors tended to be located lower in the rectum in the side-to-end anastomosis group than in the end-to-end anastomosis group. No significant differences were observed in other patient characteristics. The incidence of anastomotic leakage was significantly lower in the side-to-end anastomosis group than in the end-to-end anastomosis group (3/63, 4.8% vs. 18/99, 18.2%, respectively, P=0.02). No significant differences were observed in the incidence rates of other complications. Univariate and multivariate analyses revealed that a smoking habit (P=0.04) and side-to-end anastomosis (P=0.02) were significantly associated with anastomotic leakage. In conclusion, side-to-end anastomosis using a double-stapling technique following anterior resection for rectal cancer may prevent anastomotic leakage.

Pancreatic serous cystadenocarcinoma diagnosed with liver metastasis at 7 years after the resection of the primary serous neoplastic lesion.

Pancreatic serous neoplasms are rare tumors that are usually benign. However, histopathological differentiation between benign (serous cystadenoma) and malignant (serous cystadenocarcinoma) lesions is difficult. We present the case of a patient with pancreatic serous cystadenocarcinoma that was diagnosed with liver metastasis 7 years after the resection of the primary serous neoplastic lesion. A woman in her 60 s was diagnosed with pancreatic serous cystadenoma based on imaging and histopathological examination findings. The tumor was resected, and the patient was followed up every 6 months to monitor tumor progression. At 7 years after the resection of the primary lesion, liver tumors showing marked flare-like contrast enhancements were detected on arterial phase computed tomography findings and on dynamic magnetic resonance imaging findings acquired 60 s after the administration of a contrast agent. Laparoscopic segmental hepatectomy of S4 and S6 was performed to resect these tumors. Histopathological examination revealed that these tumors were metastatic and developed from the primary lesion. Therefore, a diagnosis of serous cystadenocarcinoma was confirmed. The flare-like contrast enhancement around the metastatic liver lesions on computed tomography and dynamic magnetic resonance images may be an indicator of serous cystadenocarcinoma with liver metastasis that could assist in diagnosis.

Unexpected postmortem diagnoses in cases of clinically diagnosed amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a motor neuron disease that is clinically and pathologically characterized by impairment of the upper and lower motor neurons. The clinical diagnosis of ALS is not always straightforward because of the lack of specific biomarkers and clinical heterogeneity. This review presents the clinical and pathological findings of four autopsied cases that had been diagnosed with ALS before death. These cases had demonstrated definite and progressive motor neuron signs and symptoms, whereas postmortem assessment revealed miscellaneous disorders, including fungal infection, paraneoplastic syndrome, and amyloidosis. Importantly, nonmotor neuron signs and symptoms, including seizures, extra-pyramidal signs, ocular movement disorders, sensory disturbance, and dysautonomia, had also been documented during the disease course of the cases in the present study. The ALS-unlike symptoms were indicative of the "true" diagnosis in each case when those symptoms were isolated from motor neuron signs/symptoms.

Laparoscopic gastrectomy with and without prophylactic drains in gastric cancer: a propensity score-matched analysis.

BACKGROUND: The number of patients who are undergoing laparoscopic gastrectomy for treating gastric cancer is increasing. Although prophylactic drains have been widely employed following the procedure, there are few studies reporting the efficacy of prophylactic drainage. Therefore, this study assessed the efficacy of prophylactic drains following laparoscopic gastrectomy for gastric cancer. METHODS: Data of patients who received laparoscopic gastrectomy for treating gastric cancer in our institution between April 2011 and March 2017 were reviewed, and the outcomes of patients with and without a prophylactic drainage were compared. Propensity score matching was used to minimize potential selection bias. RESULTS: A total of 779 patients who underwent surgery for gastric cancer were reviewed; of these, 628 patients who received elective laparoscopic gastrectomy were included in this study. After propensity score matching, data of 145 pairs of patients were extracted. No significant differences were noted in the incidence of postoperative complications between the drain and no-drain groups (19.3% vs 11.0%, P = 0.071). The days after the surgery until the initiation of soft diet (6.3 ± 7.4 vs 4.9 ± 2.9 days, P = 0.036) and the length of postoperative hospital stay (15.7 ± 12.9 vs 13.0 ± 6.3 days, P = 0.023) were greater in the drain group than those in the no-drain group. CONCLUSIONS: This study suggests that routinely using prophylactic drainage following laparoscopic gastrectomy for treating gastric cancer is not obligatory.

[A case of myasthenia gravis and myositis induced by pembrolizumab].

A 77-year-old woman with lung adenocarcinoma noticed bilateral ptosis 7 weeks after a first pembrolizumab infusion. Her symptoms rapidly progressed to generalized manifestations including limb and neck weakness, dyspnea, and dysphasia within the following two weeks. We diagnosed him with pembrolizumab-related myasthenia gravis and myositis based on clinical symptoms, elevation of muscle enzymes and anti-acetylcholine receptor antibodies, repetitive nerve stimulation and muscle biopsy. We commenced combination immunotherapy, including intravenous and oral steroid therapy, immune absorption therapy and plasma exchange therapy with noninvasive positive-pressure ventilation and tracheotomy positive pressure ventilation. She had gradual symptoms improvement and discharged after 209 days in a hospital. In this case, anti-titin antibodies, one of anti-striational antibodies, was positive and correlated with severity of myasthenia gravis. With the development of immune checkpoint inhibitors for various malignancies, clinicians should closely monitor patients for important immune-related adverse events and coordinate on early treatment.

RpA1 ameliorates symptoms of mutant ataxin-1 knock-in mice and enhances DNA damage repair.

DNA damage and repair is a critical domain of many neurodegenerative diseases. In this study, we focused on RpA1, a candidate key molecule in polyQ disease pathologies, and tested the therapeutic effect of adeno-associated virus (AAV) vector expressing RpA1 on mutant Ataxin-1 knock-in (Atxn1-KI) mice. We found significant effects on motor functions, normalized DNA damage markers (γH2AX and 53BP1), and improved Purkinje cell morphology; effects that lasted for 50 weeks following AAV-RpA1 infection. In addition, we confirmed that AAV-RpA1 indirectly recovered multiple cellular functions such as RNA splicing, transcription and cell cycle as well as abnormal morphology of dendrite and dendritic spine of Purkinje cells in Atxn1-KI mice. All these results suggested a possibility of gene therapy with RpA1 for SCA1.

[Case of rapidly progressive syringomyelia due to a spinal hemangioblastoma].

A 35-year-old man came to the hospital showing signs of worsening dysesthesia on his right hand. The dysesthesia started on his right hand and then spread to his forearm in two months. It also appeared on his left hand transiently. Initial MR imaging revealed a high signal intensity lesion at Th1-Th10 with an irregular margin (presyrinx state) below C3 on T2WI. The legion extended up to the medulla oblongata rapidly. Corticosteroid therapy lead to a slight improvement in dysesthesia symptoms but did not last. Immunosuppressant was also ineffective. Further examination using Gd enhanced MR imaging in a neurosurgery clinic in a university hospital revealed a spinal tumor at the Th10 level. A tumor resection was performed and dysesthesia improved. Pathological analysis showed hemangioblastoma. Presyrinx and syrinx above Th1 disappeared after the operation. It is necessary to search the whole spine carefully for the possibility of a tumor in the case of steroid resistant progressive spinal lesions with an unknown origin. And we stress the importance of timely surgical intervention regardless of idiopathic or secondary syringomyelia. We would like to report this clinical course presenting MR imaging and discuss the mechanism of forming syringomyelia based on the hypothesis of the alteration of CSF flow.

Systems biology analysis of Drosophila in vivo screen data elucidates core networks for DNA damage repair in SCA1.

DNA damage repair is implicated in neurodegenerative diseases; however, the relative contributions of various DNA repair systems to the pathology of these diseases have not been investigated systematically. In this study, we performed a systematic in vivo screen of all available Drosophila melanogaster homolog DNA repair genes, and we tested the effect of their overexpression on lifespan and developmental viability in Spinocerebellar Ataxia Type 1 (SCA1) Drosophila models expressing human mutant Ataxin-1 (Atxn1). We identified genes previously unknown to be involved in CAG-/polyQ-related pathogenesis that function in multiple DNA damage repair systems. Beyond the significance of each repair system, systems biology analyses unraveled the core networks connecting positive genes in the gene screen that could contribute to SCA1 pathology. In particular, RpA1, which had the largest effect on lifespan in the SCA1 fly model, was located at the hub position linked to such core repair systems, including homologous recombination (HR). We revealed that Atxn1 actually interacted with RpA1 and its essential partners BRCA1/2. Furthermore, mutant but not normal Atxn1 impaired the dynamics of RpA1 in the nucleus after DNA damage. Uptake of BrdU by Purkinje cells was observed in mutant Atxn1 knockin mice, suggesting their abnormal entry to the S-phase. In addition, chemical and genetic inhibitions of Chk1 elongated lifespan and recovered eye degeneration. Collectively, we elucidated core networks for DNA damage repair in SCA1 that might include the aberrant usage of HR.

A functional deficiency of TERA/VCP/p97 contributes to impaired DNA repair in multiple polyglutamine diseases.

It is hypothesized that a common underlying mechanism links multiple neurodegenerative disorders. Here we show that transitional endoplasmic reticulum ATPase (TERA)/valosin-containing protein (VCP)/p97 directly binds to multiple polyglutamine disease proteins (huntingtin, ataxin-1, ataxin-7 and androgen receptor) via polyglutamine sequence. Although normal and mutant polyglutamine proteins interact with TERA/VCP/p97, only mutant proteins affect dynamism of TERA/VCP/p97. Among multiple functions of TERA/VCP/p97, we reveal that functional defect of TERA/VCP/p97 in DNA double-stranded break repair is critical for the pathology of neurons in which TERA/VCP/p97 is located dominantly in the nucleus in vivo. Mutant polyglutamine proteins impair accumulation of TERA/VCP/p97 and interaction of related double-stranded break repair proteins, finally causing the increase of unrepaired double-stranded break. Consistently, the recovery of lifespan in polyglutamine disease fly models by TERA/VCP/p97 corresponds well to the improvement of double-stranded break in neurons. Taken together, our results provide a novel common pathomechanism in multiple polyglutamine diseases that is mediated by DNA repair function of TERA/VCP/p97.

Multiple brainstem infarctions in a boy caused by angiitis of the basilar artery.

A 13-year-old boy was admitted to our hospital with altered states of consciousness coupled with a headache and nausea. Upon admission, the patient was afebrile and comatose with a decorticated posture and was subsequently intubated. All routine laboratory tests and cerebrospinal fluid analyses were normal. Brain T2-weighted MRI (figure 1A) revealed multiple hyperintense signals in the brainstem and cerebellum. A single gadolinium-enhanced lesion was observed in the left occipital lobe. These observations were indicative of acute disseminated encephalomyelitis (ADEM) and we subsequently started methylprednisolone pulse therapy. In the follow-up MRI study, the lesions were necrotic, suggesting changes after a stroke rather than ADEM. The MR angiography (figure 1B) and the conventional cerebral angiography (figure 1C,D) performed on days 25 and 28, respectively, revealed segmental stenoses ("beading") of the basilar artery and the left middle cerebral artery and the near occlusions of both posterior cerebral arteries with thrombus adjacent to the basilar artery bifurcation. No angiographic abnormalities were observed in the extracranial carotid and renal arteries. We diagnosed the lesions as angiitic infarctions and started plasma exchange and antiplatelet therapy.

Suppression of the novel ER protein Maxer by mutant ataxin-1 in Bergman glia contributes to non-cell-autonomous toxicity.

Non-cell-autonomous effect of mutant proteins expressed in glia has been implicated in several neurodegenerative disorders, whereas molecules mediating the toxicity are currently not known. We identified a novel molecule named multiple alpha-helix protein located at ER (Maxer) downregulated by mutant ataxin-1 (Atx1) in Bergmann glia. Maxer is an endoplasmic reticulum (ER) membrane protein interacting with CDK5RAP3. Maxer anchors CDK5RAP3 to the ER and inhibits its function of Cyclin D1 transcription repression in the nucleus. The loss of Maxer eventually induces cell accumulation at G1 phase. It was also shown that mutant Atx1 represses Maxer and inhibits proliferation of Bergmann glia in vitro. Consistently, Bergmann glia are reduced in the cerebellum of mutant Atx1 knockin mice before onset. Glutamate-aspartate transporter reduction in Bergmann glia by mutant Atx1 and vulnerability of Purkinje cell to glutamate are both strengthened by Maxer knockdown in Bergmann glia, whereas Maxer overexpression rescues them. Collectively, these results suggest that the reduction of Maxer mediates functional deficiency of Bergmann glia, and might contribute to the non-cell-autonomous pathology of SCA1.

Glial cell lineage expression of mutant ataxin-1 and huntingtin induces developmental and late-onset neuronal pathologies in Drosophila models.

BACKGROUND: In several neurodegenerative disorders, toxic effects of glial cells on neurons are implicated. However the generality of the non-cell autonomous pathologies derived from glial cells has not been established, and the specificity among different neurodegenerative disorders remains unknown. METHODOLOGY/PRINCIPAL FINDINGS: We newly generated Drosophila models expressing human mutant huntingtin (hHtt103Q) or ataxin-1 (hAtx1-82Q) in the glial cell lineage at different stages of differentiation, and analyzed their morphological and behavioral phenotypes. To express hHtt103Q and hAtx1-82Q, we used 2 different Gal4 drivers, gcm-Gal4 and repo-Gal4. Gcm-Gal4 is known to be a neuroglioblast/glioblast-specific driver whose effect is limited to development. Repo-Gal4 is known to be a pan-glial driver and the expression starts at glioblasts and continues after terminal differentiation. Gcm-Gal4-induced hHtt103Q was more toxic than repo-Gal4-induced hHtt103Q from the aspects of development, locomotive activity and survival of flies. When hAtx1-82Q was expressed by gcm- or repo-Gal4 driver, no fly became adult. Interestingly, the head and brain sizes were markedly reduced in a part of pupae expressing hAtx1-82Q under the control of gcm-Gal4, and these pupae showed extreme destruction of the brain structure. The other pupae expressing hAtx1-82Q also showed brain shrinkage and abnormal connections of neurons. These results suggested that expression of polyQ proteins in neuroglioblasts provided a remarkable effect on the developmental and adult brains, and that glial cell lineage expression of hAtx1-82Q was more toxic than that of hHtt103Q in our assays. CONCLUSION/SIGNIFICANCE: All these studies suggested that the non-cell autonomous effect of glial cells might be a common pathology shared by multiple neurodegenerative disorders. In addition, the fly models would be available for analyzing molecular pathologies and developing novel therapeutics against the non-cell autonomous polyQ pathology. In conclusion, our novel fly models have extended the non-cell autonomous pathology hypothesis as well as the developmental effect hypothesis to multiple polyQ diseases. The two pathologies might be generally shared in neurodegeneration.

Omi / HtrA2 is relevant to the selective vulnerability of striatal neurons in Huntington's disease.

Selective vulnerability of neurons is a critical feature of neurodegenerative diseases, but the underlying molecular mechanisms remain largely unknown. We here report that Omi/HtrA2, a mitochondrial protein regulating survival and apoptosis of cells, decreases selectively in striatal neurons that are most vulnerable to the Huntington's disease (HD) pathology. In microarray analysis, Omi/HtrA2 was decreased under the expression of mutant huntingtin (htt) in striatal neurons but not in cortical or cerebellar neurons. Mutant ataxin-1 (Atx-1) did not affect Omi/HtrA2 in any type of neuron. Western blot analysis of primary neurons expressing mutant htt also confirmed the selective reduction of the Omi/HtrA2 protein. Immunohistochemistry with a mutant htt-transgenic mouse line and human HD brains confirmed reduction of Omi/HtrA2 in striatal neurons. Overexpression of Omi/HtrA2 by adenovirus vector reverted mutant htt-induced cell death in primary neurons. These results collectively suggest that the homeostatic but not proapoptotic function of Omi/HtrA2 is linked to selective vulnerability of striatal neurons in HD pathology.

The Drosophila DCO mutation suppresses age-related memory impairment without affecting lifespan.

The study of age-related memory impairment (AMI) has been hindered by a lack of AMI-specific mutants. In a screen for such mutants in Drosophila melanogaster, we found that heterozygous mutations of DCO (DCO/+), which encodes the major catalytic subunit of cAMP-dependent protein kinase (PKA), delay AMI more than twofold without affecting lifespan or memory at early ages. AMI is restored when a DCO transgene is expressed in mushroom bodies, structures important for olfactory memory formation. Furthermore, increasing cAMP and PKA activity in mushroom bodies causes premature AMI, whereas reducing activity suppresses AMI. In Drosophila AMI consists of a specific reduction in memory dependent on the amnesiac (amn) gene. amn encodes putative neuropeptides that have been proposed to regulate cAMP levels in mushroom bodies. Notably, both the memory and AMI defects of amn mutants are restored in amn;DCO/+ double mutants, suggesting that AMI is caused by an age-related disruption of amn-dependent memory via PKA activity in mushroom bodies.