Direct infiltration of clonal plasma cells causes renal insufficiency in patients with monoclonal gammopathy of undetermined significance.

Monoclonal gammopathy of undetermined significance (MGUS) is a benign but precancerous condition that can progress to multiple myeloma. Patients with MGUS are typically monitored closely for signs of disease progression, but in some cases, they may also develop renal insufficiency, a condition known as monoclonal gammopathy of renal significance (MGRS). In MGRS, M-protein secreted by a nonmalignant or premalignant cell clone triggers renal damage by definition. Herein, we report a case of a 66-year-old Asian male with MGUS complicated by renal insufficiency. A kidney biopsy showed no evidence of renal injury mediated by M-protein; instead, the direct infiltration of clonal cells into renal tissues was observed. Although five similar cases have been previously reported, our case is unique in that the involvement of clonal cells was directly confirmed by fluorescence in situ hybridization. Our findings suggest the need to consider a novel disease concept, as this phenomenon appears to be reproduced.

Erratum: Derepression of inflammation-related genes link to microglia activation and neural maturation defect in a mouse model of Kleefstra syndrome.

[This corrects the article DOI: 10.1016/j.isci.2021.102741.].

Derepression of inflammation-related genes link to microglia activation and neural maturation defect in a mouse model of Kleefstra syndrome.

Haploinsufficiency of EHMT1, which encodes histone H3 lysine 9 (H3K9) methyltransferase G9a-like protein (GLP), causes Kleefstra syndrome (KS), a complex disorder of developmental delay and intellectual disability. Here, we examined whether postnatal supply of GLP can reverse the neurological phenotypes seen in Ehmt1 Δ/+ mice as a KS model. Ubiquitous GLP supply from the juvenile stage ameliorated behavioral abnormalities in Ehmt1 Δ/+ mice. Postnatal neuron-specific GLP supply was not sufficient for the improvement of abnormal behaviors but still reversed the reduction of H3K9me2 and spine number in Ehmt1 Δ/+ mice. Interestingly, some inflammatory genes, including IL-1ß (Il1b), were upregulated and activated microglial cells increased in the Ehmt1 Δ/+ brain, and such phenotypes were also reversed by neuron-specific postnatal GLP supply. Il1b inactivation canceled the microglial and spine number phenotypes in the Ehmt1 Δ/+ mice. Thus, H3K9me2 and some neurological phenotypes are reversible, but behavioral abnormalities are more difficult to improve depending on the timing of GLP supply.

BCR/ABL1-positive B-lymphoblastic Lymphoma Successfully Treated with Dasatinib-combined Chemotherapy.

We herein report a rare case of BCR-ABL1-positive B-lymphoblastic lymphoma (B-LBL). An 18-year-old woman had a history of persistent left-sided chest pain. Positron emission tomography showed increased metabolic activity in the fifth rib, duodenum, and pancreas. The pathological findings of the pancreas, duodenum, and bone marrow confirmed the diagnosis of B-LBL. Polymerase chain reaction of duodenum and bone marrow also revealed a minor BCR-ABL1 fusion gene. She was diagnosed with BCR-ABL1-positive B-LBL and administered dasatinib and prednisolone. She achieved complete remission two weeks after the initiation of the treatment. She received stem cell transplantation after consolidation chemotherapy and sustained complete remission.

Haploidentical Hematopoietic Cell Transplantation Using Posttransplant Cyclophosphamide for Sézary Syndrome.

Patients with advanced-stage mycosis fungoides (MF) and Sézary syndrome (SS) have a poor prognosis. Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative treatment option; however, since most patients with MF/SS are elderly, they often have difficulty in finding HLA-matched donors. In recent years, HCT from HLA-haploidentical donors (haplo-HCT) using posttransplant cyclophosphamide (PTCy) as graft-versus-host disease prophylaxis has been conducted for patients without HLA-matched donors. Infectious complications, particularly cutaneous bacterial infections, are common among patients with MF/SS. The lower incidence of severe infectious complications after haplo-HCT than after an unrelated cord blood transplantation could lead to lower transplant-related mortality. Here, we report on a patient with SS who was treated successfully with haplo-HCT with PTCy. The patient has remained in complete remission for more than 24 months.

Prognostic significance of ß2-adrenergic receptor expression in malignant melanoma.

Recent studies cite ß2-adrenergic receptor (ß2AR) antagonists as novel therapeutic agents for melanoma, as they may reduce the disease progression. The ß2AR has shown to be expressed in malignant melanoma. However, it remains unclear whether the ß2AR expression has a clinical and pathological significance in patients with cutaneous malignant melanoma. We herein conducted a clinicopathological study to investigate the protein expression of ß2AR in malignant melanoma of the skin and its prognostic significance. One hundred thirty-three patients with surgically resected cutaneous malignant melanoma were evaluated. Tumor sections were stained by immunohistochemistry for ß2AR, Ki-67, the microvessel density (MVD) determined by CD34, and p53. ß2AR was highly expressed in 44.4 % (59 out of 133) of the patients. The expression of ß2AR was significantly associated with the tumor thickness, ulceration, T factor, N factor, disease stage, tumor size, cell proliferation (Ki-67), and MVD (CD34). Using Spearman's rank test, the ß2AR expression was correlated with Ki-67 (r = 0.278; 95 % CI, 0.108 to 0.432; P = 0.001), CD34 (r = 0.445; 95 %CI, 0.293 to 0.575; P < 0.001), and the tumor size (r = 0.226; 95 % CI, 0.053 to 0.386; P = 0.008). Using a univariate analysis, the tumor thickness, ulceration, disease stage, ß2AR, Ki-67, and CD34 had a significant relationship with the overall and progression-free survivals. A multivariable analysis confirmed that ß2AR was an independent prognostic factor for predicting a poor overall survival (HR 1.730; 95 % CI 1.221-2.515) and progression-free survival (HR 1.576; 95 % CI 1.176-2.143) of malignant melanoma of the skin. ß2AR can serve as a promising prognostic factor for predicting a worse outcome after surgical treatment and may play an important role in the development and aggressiveness of malignant melanoma.

Prognostic significance of L-type amino acid transporter 1 (LAT1) expression in cutaneous melanoma.

Amino acid transporters play a crucial role in the development and invasiveness of cancer cells. However, it remains unclear whether or not the expression of L-type amino acid transporter 1 (LAT1) has prognostic significance in patients with cutaneous melanoma. A total of 128 patients with cutaneous melanoma were evaluated. Tumor sections were stained by immunohistochemistry for LAT1, CD98, Ki-67, and microvessel density determined by CD34 and p53. We also analyzed 30 specimens of patients with melanocytic nevi as negative controls. LAT1 and CD98 were highly expressed in 58% (75/128) and 75% (97/128), respectively. The rates of positivity for LAT1 in the melanocytic nevi were 0% (0/30). The expression of LAT1 was associated significantly with tumor thickness, T factor, CD98 expression, cell proliferation (Ki-67), and microvessel density (CD34). By Spearman's rank test, LAT1 expression was correlated with CD98, Ki-67, and CD34. By univariate analysis, tumor thickness, ulceration, disease staging, LAT1, and CD34 showed a significant relationship with overall survival and disease-free survival. Furthermore, a multivariate analysis confirmed that LAT1 was an independent prognostic factor for predicting a poor prognosis. This study had a small sample size. LAT1 can serve as a significant prognostic factor to predict a poor outcome and it may therefore play an important role in the aggressiveness of cutaneous melanoma.

An autosomal recessive mutation of DSG4 causes monilethrix through the ER stress response.

Monilethrix is a hair shaft anomaly characterized by beaded hair with periodic changes in hair thickness. Mutations in the desmoglein 4 (DSG4) gene reportedly underlie the autosomal recessive form of the disease. However, the pathogenesis and cellular basis for the DSG4 mutation-induced monilethrix remained largely unknown. We report a Japanese female patient with monilethrix. Observation of her hair shaft by means of transmission electron microscopy showed fewer desmosomes and abnormal keratinization. Genetic analysis revealed a homozygous mutation, c.2119delG (p.Asp707Ilefs*109), in the DSG4 gene, which was predicted to cause a frameshift and premature termination in the intracellular region of the DSG4 protein. The mutation has not been reported previously. In the patient's hair shaft, we detected reduced but partial expression of the mutant DSG4 protein. Cellular analyses demonstrated that the mutant DSG4 lost its affinity to plakoglobin and accumulated in the endoplasmic reticulum (ER). The amounts of mutant DSG4 were increased by proteasome inhibitor treatment, and the expression of an ER chaperone, GRP78/BiP, was elevated in the patient's skin. Collectively, these results suggest that the dysfunctional mutated DSG4, tethered in the ER, undergoes ER-associated degradation, leading to unfolded protein response induction, and thus ER stress may have a role in the pathogenesis of monilethrix.

Successful treatment of genital Bowen's disease with imiquimod 5% cream.

A 64-year-old Japanese woman was diagnosed as having Bowen's disease on the vulva. The histopathological findings revealed papillomatosis, koilocytosis and clumping cells with atypical nuclei. Human papillomavirus DNA was not detected on polymerase chain reaction using consensus primers. The lesion was successfully treated with topical imiquimod 5% cream after two months. Histopathologically, no atypical cells were observed after treatment. Imiquimod can be a potential treatment modality for lesions that are difficult to treat with surgical excision.

Bowenoid papulosis successfully treated with imiquimod 5% cream.

A 24-year-old healthy Japanese female was diagnosed as having bowenoid papulosis in the genital area. The histopathological findings revealed acanthosis, papillomatosis, dyskeratotic cells and clumping cells with mild atypical nuclei. Human papillomavirus type 16 was detected in the lesion. The lesion was successfully treated with topical imiquimod 5% cream after 2 months. Imiquimod 5% cream is a potentially effective treatment modality for lesions that are difficult to treat with surgical excision.

Pigmented condyloma acuminatum.

We herein report a case of pigmented condyloma acuminatum in the genital region. A histopathological examination revealed keratinocyte proliferation, papillomatosis and basal pigmentation. Cellular atypia was rarely observed. The patient also had ordinary skin-colored nodules on the coronal sulcus. Polymerase chain reaction amplification with consensus primers for human papillomavirus (HPV) and subsequent sequencing confirmed an infection of HPV type 6. Pigmented condyloma acuminatum is not rare; however, making the differential diagnosis between bowenoid papulosis and seborrheic keratosis is sometimes difficult. The mechanism of pigmentation in such cases remains unknown and requires further investigation. HPV typing is a useful method for diagnosing the disease.