An extra-erythrocyte role of haemoglobin body in chondrocyte hypoxia adaption.

Although haemoglobin is a known carrier of oxygen in erythrocytes that functions to transport oxygen over a long range, its physiological roles outside erythrocytes are largely elusive1,2. Here we found that chondrocytes produced massive amounts of haemoglobin to form eosin-positive bodies in their cytoplasm. The haemoglobin body (Hedy) is a membraneless condensate characterized by phase separation. Production of haemoglobin in chondrocytes is controlled by hypoxia and is dependent on KLF1 rather than the HIF1/2α pathway. Deletion of haemoglobin in chondrocytes leads to Hedy loss along with severe hypoxia, enhanced glycolysis and extensive cell death in the centre of cartilaginous tissue, which is attributed to the loss of the Hedy-controlled oxygen supply under hypoxic conditions. These results demonstrate an extra-erythrocyte role of haemoglobin in chondrocytes, and uncover a heretofore unrecognized mechanism in which chondrocytes survive a hypoxic environment through Hedy.

Clinical Genetic Features and Neoadjuvant Chemotherapy Response in HER2-Low Breast Cancers: A Retrospective, Multicenter Cohort Study.

BACKGROUND: The objective of this work is to reveal differences in clinical and genetic features, as well as neoadjuvant chemotherapy (NAC) response, between HER2-low and HER2-zero or HER2-positive breast cancers. PATIENTS AND METHODS: A total of 245 female patients with breast cancer were retrospectively enrolled from seven hospitals. Core needle biopsy (CNB) samples were collected before NAC and used for next-generation sequencing by a commercial gene panel. Clinical and genetic features, as well as NAC response, were compared between HER2-low and HER2-zero or HER2-positive breast cancers. The nonnegative matrix factorization (NMF) method was applied to cluster the C-Score of enrolled cases to reveal the intrinsic features of each HER2 subgroup. RESULTS: A total of 68 (27.8%) cases are HER2-positive, 117 (47.8%) cases are HER2-low, and 60 (24.5%) cases are HER2-zero. HER2-low breast cancers have a significantly lower pathologic complete response (pCR) rate than HER2-positive and HER2-zero breast cancers (p < 0.050 for all comparisons). Compared with HER2-low breast cancers, HER2-positive cases have higher rates of TP53 mutation, TOP2A amplification, and ERBB2 amplification, as well as lower rates of MAP2K4 mutation, ESR1 amplification, FGFR1 amplification, and MAPK pathway alteration (p < 0.050 for all comparisons). After clustering HER2-low cases by the NMF method, 56/117 (47.9%) are in cluster 1, 51/117 (43.6%) are in cluster 2, and 10/117 (8.5%) are in cluster 3. HER2-low cases in cluster 2 have the lowest pCR rate among the three clusters (p < 0.050). CONCLUSIONS: HER2-low breast cancers have significant genetic differences from HER2-positive cases. Genetic heterogeneity exists in HER2-low breast cancers and impacts on NAC response in this subgroup.

The clinicopathological and molecular features of sinusoidal large B-cell lymphoma.

We report 17 cases of sinusoidal large B-cell lymphoma (SLBCL). Clinical, morphologic, immunophenotypic, and molecular features were detected and analyzed. All cases showed an obvious sinusoidal growth pattern, usually associated with residual atrophic lymphoid tissue. All tumors contained large pleomorphic lymphoid cells and one or more prominent nucleoli, with abundant amphophilic cytoplasms; 15/17 cases showed anaplastic morphologic features. The patient age ranged from 43 to 80 years (median 57 years), and 7 males and 10 females were included. Eleven of 15 (73.3%) patients had Ann Arbor stage III or IV disease, and 10/15 (66.6%) patients had an International Prognostic Index (IPI) score ≥3. Immunophenotypically, 16/17 (94.1%) cases displayed a nongerminal center B-cell (non-GCB) immunophenotype. Furthermore, 16/17 (94.1%) cases were positive for CD30, and p53 was expressed in 10/16 (62.5%) cases. In total, 12/14 (85.7%) cases expressed BCL2 and MYC simultaneously (double expression), and 11/14 (78.6%) cases showed PD-L1 positivity (6/11 had a PD-L1 tumor proportion score ≥50%). Cytogenetically, concurrent MYC and BCL2 and/or BCL6 abnormalities (break-apart or extra copy) were detected in 10/15 cases, and 7/13 (53.8%) cases harbored a PD-L1/L2 amplification. TP53 mutation was found in 7/13 (53.8%) cases by Sanger sequencing. Whole-exome and large-panel sequencing results revealed high mutation frequencies of TP53 (4/7), MYD88 (3/7), KMT2D (3/7), CREBBP (3/7), and PIM1 (3/7). Among the 13 patients with SLBCL treated with aggressive chemotherapy regimens, the median overall survival (OS) was 18 months, and the 2-year OS rate was 34.6%. The OS of patients with SLBCL was markedly worse than that of 35 control group patients with common diffuse large B-cell lymphoma (DLBCL) without sinusoidal features (P < 0.001). SLBCL may represent a specific type of DLBCL that has characteristic pathologic features. The cancer is aggressive in most clinical cases, and outcomes are poor. SLBCL and anaplastic DLBCL (A-DLBCL) have many overlapping clinicopathological and molecular features.

Some pleomorphic adenomas of the breast share PLAG1 rearrangements with the analogous tumour of the salivary glands.

AIMS: Pleomorphic adenoma (PA) of the breast, and especially its malignant transformation, is extremely rare and represents a diagnostic pitfall. Molecular alterations in this entity have not been investigated. We aimed to examine the clinicopathological features of our breast PAs and perform molecular analysis. METHODS AND RESULTS: Seven cases of breast PA, including two cases of carcinoma ex PA, were analysed. PLAG1 and HMGA2 gene rearrangements were assayed by fluorescence in-situ hybridisation (FISH) and RNA sequencing (RNA-Seq), respectively. Reverse transcription-polymerase chain reaction (RT-PCR) and Sanger sequencing were used to verify RNA sequencing results. All seven cases of breast PA occurred in women. The histological features were similar to the analogous tumour in salivary glands, including a dual epithelial-myoepithelial component and negativity of oestrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) by immunohistochemistry. Of the two cases with carcinoma ex PA, one demonstrated minimal invasion and one was extensively invasive. PLAG1 rearrangements were identified in two cases (28.6%), but no rearrangements of HMG2A were found. A novel fusion product in PAs, TRPS1-PLAG1, was identified in one case. No patients had recurrence or metastasis with a follow-up period of 6-158 months. CONCLUSIONS: Breast PA is rare, but it is an important differential diagnosis of breast pathology with the potential to develop carcinoma ex PA. We report a novel TRPS1-PLAG1 fusion gene in breast PA.

Genetic alterations in cell cycle regulation-associated genes may promote primary progression of gastrointestinal stromal tumors.

Gastrointestinal stromal tumors (GISTs) are one of the most common mesenchymal tumor types and usually contain KIT or PDGFRA mutations. GISTs with concomitant low- and high-grade components are seen in clinical practice. Herein, we retrospectively analyzed the histological characteristics and immunohistochemical results of 22 GIST cases with concomitant low- and high-grade tumors. Whole-exome sequencing (WES) was performed on ten pairs of high-grade GIST specimens and matched low-grade samples. Differential oncogenes mutated only in high-grade GISTs were identified, which were confirmed by Sanger sequencing. Fluorescence in situ hybridization was employed to detect MYC copy number variation. High-grade GISTs were more likely to have lower CD34 expression and a higher Ki-67 proliferation index compared to the matched low-grade tumors. WES identified 30 differential cancer-associated genes mutated only in high-grade GISTs; Sanger sequencing confirmed ten relevant differential oncogenic mutations in nine genes (MGA, ARID1A, LATS2, MAX, PIK3CA, RB1, RPS6KB2, SDHA, and SETD2). Two patients had MGA mutations, whereas other gene mutations occurred in only one patient. Most of the differential cancer-associated genes are mainly involved in cell cycle control. MYC copy number gain was a common genetic variation. High-grade GISTs revealed more MYC copy number gains than matched low-grade tumors, and low-grade GISTs with coexisting high-grade components showed more MYC copy number gains than pure low-grade GISTs. Moreover, MYC copy number gain was positively correlated with the mitotic index and Ki-67 proliferation index. Alterations in cell cycle regulation-associated genes, such as genetic mutations and MYC copy number gain, may promote primary progression from low-grade GISTs to high-grade tumors by regulating tumor cell proliferation.

Global microRNA expression profiling uncovers molecular markers for classification and prognosis in aggressive B-cell lymphoma.

We studied the global microRNA (miRNA) expression in diffuse large B-cell lymphoma (DLBCL; n = 79), Burkitt lymphoma (BL; n = 36), primary mediastinal B-cell lymphoma (PMBL; n = 12), B-cell lines (n = 11), and normal subsets of naïve B cells, centroblasts (CBs), and peripheral blood B cells along with their corresponding gene expression profiles (GEPs). The normal B-cell subsets have well-defined miRNA signatures. The CB miRNA signature was significantly associated with germinal center B-cell (GCB)-DLBCL compared with activated B-cell (ABC)-DLBCL (P = .002). We identified a 27-miRNA signature that included v-myc avian myelomatosis viral oncogene homolog (MYC) targets and enabled the differentiation of BL from DLBCL, a distinction comparable with the "gold standard" GEP-defined diagnosis. Distinct miRNA signatures were identified for DLBCL subgroups, including GCB-DLBCL, activated B-cell (ABC)-DLBCL, and PMBL. Interestingly, most of the unclassifiable-DLBCL by GEP showed a strong similarity to the ABC-DLBCL by miRNA expression profiling. Consistent results for BL and DLBCL subgroup classification were observed in formalin-fixed, paraffin-embedded tissue, making such tests practical for clinical use. We also identified predictive miRNA biomarker signatures in DLBCL, including high expression of miR-155, which is significantly associated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) treatment failure. This finding was further supported by the observation that high expression of miR-155 sensitizes cells to v-akt murine thymoma viral oncogene homolog-1 inhibitors in vitro, suggesting a novel treatment option for resistant DLBCL.

BRAFV600E and MAP2K1 mutations in Langerhans cell histiocytosis occur predominantly in children.

Langerhans cell histiocytosis (LCH) is a proliferative disease of CD1a+ /CD207+ dendritic cells. Recurrent BRAFV600E and MAP2K1 mutations have been reported in LCH. To investigate the relationship among the mutation, clinical findings, and differentiation status of LCH, respectively, we studied 97 cases of LCH by using Sanger sequencing and immunohistochemistry. The mutually exclusive BRAFV600E and MAP2K1 mutation rates were 32% and 17.5%, respectively. All MAP2K1 mutations were missense mutations without any in-frame deletions; 2 new recurrent missense mutations (ie, p.E38K and p.P105S) were also found. More BRAFV600E and MAP2K1 mutations occurred in children compared with those in adult patients (P = .001), and BRAF mutation was correlated with relapse (P = .009). To the differentiation-related markers, the BRAF/MAP2K1-mut LCH expressed CD14 but rarely expressed CD83 or CD86 (P < .001). On the contrary, BRAF/MAP2K1-wt LCH cells rarely expressed CD14 but expressed CD86, and some also expressed CD83 (P < .001). This indicated that the BRAF/MAP2K1-mut LCH cells had a more immature state than BRAF/MAP2K1-wt LCH cells. Moreover, we also found the BRAFV600E and MAP2K1 mutations were significantly associated with pERK expression (P < .001). Therefore, the RAS/RAF/MEK/ERK pathway might play a more important role in children than in adult patients with LCH.

Gene expression signatures delineate biological and prognostic subgroups in peripheral T-cell lymphoma.

Peripheral T-cell lymphoma (PTCL) encompasses a heterogeneous group of neoplasms with generally poor clinical outcome. Currently 50% of PTCL cases are not classifiable: PTCL-not otherwise specified (NOS). Gene-expression profiles on 372 PTCL cases were analyzed and robust molecular classifiers and oncogenic pathways that reflect the pathobiology of tumor cells and their microenvironment were identified for major PTCL-entities, including 114 angioimmunoblastic T-cell lymphoma (AITL), 31 anaplastic lymphoma kinase (ALK)-positive and 48 ALK-negative anaplastic large cell lymphoma, 14 adult T-cell leukemia/lymphoma and 44 extranodal NK/T-cell lymphoma that were further separated into NK-cell and gdT-cell lymphomas. Thirty-seven percent of morphologically diagnosed PTCL-NOS cases were reclassified into other specific subtypes by molecular signatures. Reexamination, immunohistochemistry, and IDH2 mutation analysis in reclassified cases supported the validity of the reclassification. Two major molecular subgroups can be identified in the remaining PTCL-NOS cases characterized by high expression of either GATA3 (33%; 40/121) or TBX21 (49%; 59/121). The GATA3 subgroup was significantly associated with poor overall survival (P = .01). High expression of cytotoxic gene-signature within the TBX21 subgroup also showed poor clinical outcome (P = .05). In AITL, high expression of several signatures associated with the tumor microenvironment was significantly associated with outcome. A combined prognostic score was predictive of survival in an independent cohort (P = .004).

Phosphorylation of PBK/TOPK Tyr74 by JAK2 promotes Burkitt lymphoma tumor growth.

Burkitt lymphoma (BL), which is characterized by high invasiveness, is a subgroup of non-Hodgkin lymphoma. Although BL is regarded as a highly curable disease, especially for children, some patients unfortunately still do not respond adequately. The understanding of the etiology and molecular mechanisms of BL is still limited, and targeted therapies are still lacking. Here, we found that T-LAK cell-derived protein kinase (TOPK) and phosphorylated Janus kinase 2 (p-JAK2) are highly expressed in the tissues of BL patients. We report that TOPK directly binds to and is phosphorylated at Tyr74 by JAK2. Histone H3, one of the downstream targets of TOPK, is also phosphorylated in vivo and in vitro. Furthermore, we report that the phosphorylation of TOPK at Tyr74 by JAK2 plays a vital role in the proliferation of BL cells and promotes BL tumorigenesis in vivo. Phosphorylation of TOPK at Tyr74 by JAK2 enhances the stability of TOPK. Collectively, our results suggest that the JAK2/TOPK/histone H3 axis plays a key role in the proliferation of BL cells and BL tumorigenesis in vivo.

Joint Landmark and Structure Learning for Automatic Evaluation of Developmental Dysplasia of the Hip.

The ultrasound (US) screening of the infant hip is vital for the early diagnosis of developmental dysplasia of the hip (DDH). The US diagnosis of DDH refers to measuring alpha and beta angles that quantify hip joint development. These two angles are calculated from key anatomical landmarks and structures of the hip. However, this measurement process is not trivial for sonographers and usually requires a thorough understanding of complex anatomical structures. In this study, we propose a multi-task framework to learn the relationships among landmarks and structures jointly and automatically evaluate DDH. Our multi-task networks are equipped with three novel modules. Firstly, we adopt Mask R-CNN as the basic framework to detect and segment key anatomical structures and add one landmark detection branch to form a new multi-task framework. Secondly, we propose a novel shape similarity loss to refine the incomplete anatomical structure prediction robustly and accurately. Thirdly, we further incorporate the landmark-structure consistent prior to ensure the consistency of the bony rim estimated from the segmented structure and the detected landmark. In our experiments, 1231 US images of the infant hip from 632 patients are collected, of which 247 images from 126 patients are tested. The average errors in alpha and beta angles are 2.221 ° and 2.899 °. About 93% and 85% estimates of alpha and beta angles have errors less than 5 degrees, respectively. Experimental results demonstrate that the proposed method can accurately and robustly realize the automatic evaluation of DDH, showing great potential for clinical application.

RNA-binding protein LIN28 is a marker for primary extragonadal germ cell tumors: an immunohistochemical study of 131 cases.

LIN28 has been shown to have an important role in primordial germ cell development and malignant transformation of germ cells in mouse. In this study, we examined the immunohistochemical profile of LIN28 in 131 primary human extragonadal germ cell tumors (central nervous system (CNS) 76, mediastinum 17, sacrococcygeal region 30, pelvis 3, vagina 2, liver 1, omentum 1, and retroperitoneum 1), including the following tumors and/or components: 57 seminomas/germinomas, 10 embryonal carcinomas, 74 yolk sac tumors, 6 choriocarcinomas, 15 mature, and 13 immature teratomas. We compared LIN28 with SALL4 to assess its diagnostic value. To determine its specificity, we examined LIN28 in 406 extragonadal-non-germ cell tumors (103 carcinomas, 91 sarcomas, 9 melanomas, 12 mesotheliomas, 83 lymphomas, 9 plasmacytomas, 82 CNS tumors, and 17 thymic epithelial tumors). The staining was semi-quantitatively scored as 0 (no cell stained), 1+ (0-30%), 2+ (31-60%), 3+ (61-90%), and 4+ (>90%). LIN28 staining was seen in all seminomas/germinomas (3+ in 1 and 4+ in 56), embryonal carcinomas (4+ in all 10), and yolk sac tumors (3+ in 3 and 4+ in 71). Variable LIN28 staining was seen in 5 of 6 choriocarcinomas (1+ to 4+), 8 of 13 immature teratomas (1+ to 2+ in immature elements), and in 1 of 15 mature teratomas (1+). Only 11 of 406 non-germ cell tumors showed 1+ LIN28 staining. Therefore, LIN28 is a sensitive (100% sensitivity) marker for primary extragonadal seminomas/germinomas, embryonal carcinomas, and yolk sac tumors with high specificity. Compared with SALL4, LIN28 demonstrated a similar level of diagnostic sensitivity for seminomas/germinomas and embryonal carcinomas. For primary extragonadal yolk sac tumors, although SALL4 stained all tumors (1+ in 1, 2+ in 2, 3+ in 10, and 4+ in 61), LIN28 stained more tumor cells (mean 95 vs 90%, P = 0.03) and was therefore more sensitive. For primary extragonadal yolk sac tumors, combining LIN28 and SALL4 can achieve a higher diagnostic sensitivity than either alone.

p63 expression is associated with high histological grade, aberrant p53 expression and TP53 mutation in HER2-positive breast carcinoma.

AIM: p63, a member of the p53 family, is a myoepithelial cell marker usually expressed in metaplastic breast carcinoma and its expression suggests a myoepithelial phenotype. However, its expression and association with clinicopathological features of human epidermal growth factor receptor 2 (HER 2)-positive breast carcinoma is poorly investigated. MATERIALS AND METHODS: Sixty-seven patients with oestrogen receptor-negative and progesterone receptor-negative, HER2-positive breast carcinoma who received anti-HER2-based neoadjuvant±adjuvant therapy was retrospectively analysed. RESULTS: Twenty cases were p63-positive and 47 cases were p63-negative. The clinicopathological features and tumour responses after neoadjuvant therapy and outcomes were analysed. Among HER2-positive tumours, expression of p63 was significantly associated with younger age (42.5 vs 55.9; p=0.010). Expression of p63 was also significantly associated with histological grade 3 (11/20 (55%) vs 11/47 (23.4%); p=0.012) and negatively associated with grade 2 (9/20 (45%) vs 36/47 (76.6%); p=0.012). Intriguingly, p63-positive breast carcinomas showed significant aberrant p53 expression by immunohistochemistry (16/18 (88.9%) vs 29/47 (61.7%); p=0.03) and of TP53 mutation by Sanger sequencing (15/16 (93.8%) vs 12/22 (54.5%); p=0.009). No significant difference in tumour response after anti-HER2 neoadjuvant therapy nor in survival were found between p63-positive and p63-negative breast carcinomas. CONCLUSION: Expression of p63 in HER2-positive breast carcinoma is significantly associated with younger age, poor differentiation, high histological grade and aberrant expression of p53 and of TP53 mutation. HER2-positive breast carcinoma with a myoepithelial immunophenotype shows distinctive clinicopathological features representing a distinct subtype of HER2-positive breast carcinoma. Further, these findings suggest an interaction between p63 and mutant p53 in the tumorigenesis of HER2-positive breast carcinomas.

Poor histologic tumor response after adjuvant therapy in basal-like HER2-positive breast carcinoma.

AIMS: HER2-positive breast carcinomas are all treated with first-line anti-HER2 therapy. However, immunohistochemical and molecular profiling demonstrates significant heterogeneity among HER2-positive carcinomas. Basal-like HER2-positive breast carcinomas are poorly differentiated from pure HER2-positive breast carcinomas. MATERIALS AND METHODS: Seventy-five patients with HER2-positive, ER- and PR-negative breast carcinomas who received anti-HER2 based neoadjuvant therapy were retrospectively analyzed. Thirty-seven cases were classified as basal-like HER2-positive breast carcinoma with any positivity for CK5/6, and thirty-eight cases were classified as pure HER2-positive breast carcinoma with completely negativity for CK5/6. The clinicopathological features and tumor responses after neoadjuvant therapy and outcomes were analyzed. RESULTS: Compared to non-basal HER2-positive breast carcinoma, basal-like HER2-positive breast carcinoma showed distinctive histologic features including poor differentiation and syncytial tumor cells with pushing, invasive borders and a significantly higher proportion of apocrine metaplasia. They also demonstrated significantly higher histologic grade; 18/37 (48.6%) of basal-like carcinomas were grade 3, whereas only 5/38 (13.2%) of non-basal carcinomas were grade 3 (p = 0.001), Furthermore, basal-like HER2-positive breast carcinomas were more likely to be positive or completely negative for p53 (p = 0.009), and demonstrated a higher percentage of TP53 mutation (p = 0.17). These tumors were less responsive to anti-HER2 based neoadjuvant therapy, with Miller-Payne grades 1-3 higher than pure HER2-positive breast carcinoma (25/37 [67.6%] vs 16/38 [42.1%]), and the percentage of grade 4-5 was lower (12/37 [32.4%] vs 22/38 [57.9%]; p = 0.027). CONCLUSIONS: Basal-like HER2-positive breast carcinoma has distinctive clinicopathological features and less histologic tumor response after neoadjuvant therapy. There is urgent need to recognize basal-like HER2-positive breast carcinoma to be treated precisely.

Decreased infiltration of CD4+ Th1 cells indicates a good response to ursodeoxycholic acid (UDCA) in primary biliary cholangitis.

BACKGROUND: Primary biliary cholangitis (PBC) is characterized by nonsuppurative destructive cholangitis and is thought to be an autoimmune disorder. Currently, ursodeoxycholic acid (UDCA) is the only FDA approved first-line therapy for PBC, but up to nearly one-third of patients do not achieve a complete response to this treatment. Adaptive immune cells, including T cells and B cells, have been found in the portal tracts and the bile duct epithelium and play a role in the pathogenesis of PBC, but the importance of these cells for evaluating the therapeutic response to UDCA in PBC has not yet been studied. METHODS: In this study, we collected liver puncture biopsy specimens from 34 matched patients with PBC before and after UDCA treatment and investigated the relationship between the infiltration of adaptive immune cells and the treatment response to UDCA. The extent of immune cell infiltration was determined by immunohistochemical analysis. Responses were defined based on Paris-I criteria. RESULTS: After 1 year of treatment, 25/34 patients responded to UDCA treatment according to Paris-I criteria (responders), and 9/34 patients were nonresponders. Immunohistochemical analysis showed that UDCA responders exhibited significantly less CD4+ T cell infiltration after UDCA treatment than before (50.4 ± 7.5/HPF vs 30.0 ± 7.9/HPF, P = 0.002). In contrast, UDCA nonresponders exhibited significantly more CD4+ T cell infiltration after UDCA treatment than before (32.2 ± 8.0/HPF vs 75.0 ± 13.9/HPF, P = 0.045). Moreover, patients who exhibited a reduction in CD4+ T cell infiltration after UDCA treatment had a higher response rate than those that exhibited an increase in CD4+ T cell infiltration (85.7 % vs 53.8 %, P = 0.041). However, CD3+ T cell, CD8+ T cell, and CD20+ B cell infiltration was not significantly different before and after treatment in either UDCA responders or nonresponders. Furthermore, we found that the number of infiltrating T-bet+ Th1 cells was much lower after UDCA treatment than before in responders (10.5 ± 5.7/HPF vs. 5.16 ± 4.0/HPF, P = 0.0214) but much higher in nonresponders after treatment than before (1.89±1.2/HPF vs. 12.3±5.4/HPF, P = 0.043). However, there was no difference in the extent of GATA3+ Th2 or FOXP3+ Treg infiltration before and after treatment in either UDCA responders or nonresponders. CONCLUSION: Collectively, our results suggest that a decrease in the number of liver-infiltrating CD4+ Th1 cells is associated with a good response of PBC patients to UDCA treatment. Immunohistochemical analysis of CD4 and T-bet in PBC liver specimens may be a potential approach for evaluating the therapeutic response to UDCA.

Identification of Jmjd3 as an Essential Epigenetic Regulator of Hox Gene Temporal Collinear Activation for Body Axial Patterning in Mice.

Body axial patterning develops via a rostral-to-caudal sequence and relies on the temporal colinear activation of Hox genes. However, the underlying mechanism of Hox gene temporal colinear activation remains largely elusive. Here, with small-molecule inhibitors and conditional gene knockout mice, we identified Jmjd3, a subunit of TrxG, as an essential regulator of temporal colinear activation of Hox genes with its H3K27me3 demethylase activity. We demonstrated that Jmjd3 not only initiates but also maintains the temporal collinear expression of Hox genes. However, we detected no antagonistic roles between Jmjd3 and Ezh2, a core subunit of PcG repressive complex 2, during the processes of axial skeletal patterning. Our findings provide new insights into the regulation of Hox gene temporal collinear activation for body axial patterning in mice.

TOPK: A new predictor of the therapeutic response to neoadjuvant chemotherapy and prognosis in triple-negative breast cancer.

BACKGROUND: Triple-negative breast cancer (TNBC) has a high probability of relapse and poor overall survival. Neoadjuvant chemotherapy (NACT) is currently a routine treatment strategy for TNBC, but some patients do not respond well. T-LAK cell-originated protein kinase (TOPK) is highly expressed in breast cancer cells and contributes to cancer cell proliferation. The present study aimed to investigate the correlation of TOPK expression with NACT treatment response and prognosis in TNBC. METHODS: We collected 66 pairs of TNBC samples before and after NACT with docetaxel+ epirubicin+ cyclophosphamide (TEC). The Miller-Payne (MP) system was used to assess the therapeutic response to NACT in TNBC patients. RESULTS: Immunohistochemistry analysis showed that TNBC patients with high TOPK expression before NACT had a poor treatment response and a poor prognosis. The expression of TOPK after NACT was significantly higher than that before NACT in patients with MP grade 1-3. In contrast, patients with MP grade 4-5 had significantly lower TOPK expression after NACT than before NACT, and the expression change in Ki-67 in patients with MP grade 4-5 exhibited the same trend. Survival analysis revealed that patients with TNBC accompanied by elevated TOPK expression before NACT had a worse prognosis than those with lower TOPK expression. CONCLUSION: TOPK may be a novel predictor for the therapeutic response to NACT and prognosis for patients with TNBC.

Tumor Immune Microenvironment Components and Checkpoint Molecules in Anaplastic Variant of Diffuse Large B-Cell Lymphoma.

BACKGROUND: Anaplastic diffuse large B-cell lymphoma(A-DLBCL) is a rare morphological subtype characterized by the presence of polygonal, bizarre-shaped tumor cells. Our previous research found that A-DLBCL displays many genetic alterations and biological features that differ greatly from those of ordinary DLBCL. However, the status of tumor immune microenvironment components and checkpoint molecules in A-DLBCL remains unclear. METHODS: Thirty A-DLBCL patients were enrolled to study tumor immune microenvironment components and checkpoint molecules and their associations with clinicopathological features and prognosis. RESULTS: Patients with A-DLBCL presented higher expression of PD-L1 (40% vs 10%, P=0.004) than patients with ordinary DLBCL. FISH analysis showed that extra copies of PD-L1 were more frequent in A-DLBCL cases than in ordinary DLBCL cases (23.3% vs 4.0%, P=0.001). The numbers of PD-1+ TILs (tumor infiltrating lymphocytes) and CD8+T cells were significantly lower in A-DLBCL versus ordinary DLBCL. In contrast, the numbers of GATA3+ Th2 cells, FOXP3+ Tregs and CD33+ myeloid-derived suppressor cells (MDSCs) were significantly higher in A-DLBCL than in ordinary DLBCL. The associations between clinicopathological features and tumor immune microenvironment cell frequency were analyzed in A-DLBCL patients. Briefly, the number of PD-1+ TILs was lower and the number of CD33+ MDSCs was higher in patients with mutated TP53 compared to those with wild-type TP53. The number of FOXP3+ Tregs was much lower in patients with a noncomplete response (CR) to chemotherapy than in those with a complete response. The number of CD8+ T cells showed a decreasing trend in patients with high International Prognostic Index (IPI) scores and in those with concurrent MYC and BCL2 and/or BCL6 abnormalities. Univariate survival analysis showed that patients with PD-L1+, mPD-L1+(PD-L1+ nonmalignant stromal cells) or mPD-L1+ status had a significantly poorer overall survival (OS) than those with PD-L1- status. An increase in the number of CD3+ T cells, FOXP3+ Treg cells and T-bet+ Th1 cells was significantly associated with prolonged OS in patients with A-DLBCL. CONCLUSION: Our study suggests that A-DLBCL displays a distinct pattern of tumor immune microenvironment components and checkpoint molecules that distinguish it from ordinary DLBCL. The analysis of tumor immune microenvironment components and checkpoint molecules could help in predicting the prognosis of A-DLBCL patients and determining therapeutic strategies targeting the tumor immune microenvironment.

Genomic Mutation Profile of Primary Gastrointestinal Diffuse Large B-Cell Lymphoma.

Primary gastrointestinal diffuse large B-cell lymphoma (GI-DLBCL) is the most common gastrointestinal lymphoma, but its genetic features are poorly understood. We performed whole-exome sequencing of 25 primary tumor samples from patients with GI-DLBCL and 23 matched normal tissue samples. Oncogenic mutations were screened, and the correlations between genetic mutations and clinicopathological characteristics were analyzed. Twenty-five patients with GI-DLBCL were enrolled in the genetic mutation analysis with a median of 184 (range 79-382) protein-altering variants per patient. We identified recurrent oncogenic mutations in GI-DLBCL, including those in TP53, MUC16, B2M, CCND3, HIST1H1C, NEB, and ID3. Compared with nodal DLBCL, GI-DLBCL exhibited an increased mutation frequency of TP53 and reduced mutation frequencies of PIM1, CREBBP, BCL2, KMT2D, and EZH2. Moreover, GI-DLBCL exhibited fewer MYD88 and CD79B mutations than DLBCL in the testis and central nervous system. GI-DLBCLs with HLA-B, MEF2A, RHOA, and NAV3 mutations exhibited a tendency toward a high proliferation index. MUC16 and ETV6 mutations often occurred in tumors with early clinical staging. Our data provide a comprehensive understanding of the landscape of mutations in a small subset of GI-DLBCLs. The genetic mutation profiles of GI-DLBCL differ from those of nodal DLBCL and DLBCL in immune-privileged sites. The different mutated genes are related to the NF-κB and JAK-STAT pathways, and the different pathogenetic mechanisms leading to the development of DLBCL may be influenced by the tissue microenvironment. Differences in genetic alterations might influence the clinicopathological characteristics of GI-DLBCL.

Disruption of Jmjd3/p16Ink4a Signaling Pathway Causes Bizarre Parosteal Osteochondromatous Proliferation (BPOP)-like Lesion in Mice.

Bizarre parosteal osteochondromatous proliferation (BPOP), or Nora's lesion, is a rare benign osteochondromatous lesion. At present, the molecular etiology of BPOP remains unclear. JMJD3(KDM6B) is an H3K27me3 demethylase and counteracts polycomb-mediated transcription repression. Previously, Jmjd3 was shown to be critical for bone development and osteoarthritis. Here, we report that conditional deletion of Jmjd3 in chondrogenic cells unexpectedly resulted in BPOP-like lesion in mice. Biochemical investigations revealed that Jmjd3 inhibited BPOP-like lesion through p16Ink4a . Immunohistochemistry and RT-qPCR assays indicated JMJD3 and p16INK4A level were significantly reduced in human BPOP lesion compared with normal subjects. This was further confirmed by Jmjd3/Ink4a double-gene knockout mice experiments. Therefore, our results indicated the pathway of Jmjd3/p16Ink4a may be essential for the development of BPOP in human. © 2021 American Society for Bone and Mineral Research (ASBMR).