Recent research has focused on the mechanisms by which long non-coding RNAs (lncRNAs) modulate diverse cellular processes such as tumorigenesis. However, the functional characteristics of these non-coding elements in the genome are poorly understood at present. In this study, we have explored several mechanisms that involve the novel lncRNA and microRNA (miRNA) axis participating in modulation of drug response and the tumor microenvironment of myeloproliferative neoplasms (MPNs). We identified novel lncRNAs via mRNA sequencing that was applied to leukemic cell lines derived from BCR-ABL1-positive and JAK2-mutant MPNs under treatment with therapeutic tyrosine kinase inhibitors (TKI). The expression and sequence of novel LNC000093 were further validated in both leukemic cells and normal primary and pluripotent cells isolated from human blood, including samples from patients with chronic myelogenous leukemia (CML). Downregulation of LNC000093 was validated in TKI-resistant CML while a converse expression pattern was observed in blood cells isolated from TKI-sensitive CML cases. In addition to BCR-ABL1-positive CML cells, the driver mutation JAK2-V617F-regulated lncRNA BANCR axis was further identified in BCR-ABL1-negative MPNs. Further genome-wide validation using MPN patient specimens identified 23 unique copy number variants including the 7 differentially expressed lncRNAs from our database. The newly identified LNC000093 served as a competitive endogenous RNA for miR-675-5p and reversed the imatinib resistance in CML cells through regulating RUNX1 expression. The extrinsic function of LNC000093 in exosomal H19/miR-675-induced modulation for the microenvironment was also determined with significant effect on VEGF expression.

The coronavirus disease 2019 (COVID‐19) is a highly infectious disease caused by SARS‐CoV‐2. Since its first report in December 2019, COVID‐19 has evolved into a global pandemic causing massive healthcare and socioeconomic challenges. HLA system is critical in mediating anti‐viral immunity and recent studies have suggested preferential involvement of HLA‐B in COVID‐19 susceptibility. Here, by investigating the HLA‐B genotypes in 190 unrelated Chinese patients with confirmed COVID‐19, we identified a significant positive association between the B22 serotype and SARS‐CoV‐2 infection (p = 0.002, Bonferroni‐corrected p = 0.032). Notably, the B22 serotype has been consistently linked to susceptibility to other viral infections. These data not only shed new insights into SARS‐CoV‐2 pathogenesis and vaccine development but also guide better infection prevention/control.

Objectives/Hypothesis This study investigated olfactory and gustatory dysfunction in the 2020 novel coronavirus disease (COVID-19) patients, and their correlations with viral load evaluation. Study Design Prospective cross-sectional cohort study. Methods One hundred forty-three symptomatic patients being screened for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were invited to participate. The clinical data of 83 confirmed COVID-19 subjects were collected, with 60 patients who were symptomatic but negative for COVID-19 recruited as controls. The prevalence and severity of and recovery time for olfactory and gustatory dysfunction, and cycle threshold (Ct) values from a SARS-CoV-2 polymerase chain reaction assay of nasopharyngeal and deep throat swabs were collected. Their correlations with Ct values were reported. Results Thirty-nine (47.0%) and 36 (43.4%) COVID-19 patients reported olfactory and gustatory dysfunction, respectively. The results of one-way analysis of variance did not show statistically significant relationships between the Ct values and severity of olfactory and gustatory dysfunction (P= .780 andP= .121, respectively). Among the COVID-19 patients who reported smell and taste loss, 28/39 (71.8%) and 30/36 (83.3%) experienced complete recovery, respectively. The mean recovery time was 10.3 +/- 8.1 days for olfactory dysfunction and 9.5 +/- 6.8 days for gustatory dysfunction. The recovery time was not correlated with the Ct values (Pearson correlation coefficient, smell: -0.008,P= .968; taste: -0.015,P= .940). Conclusions There is a high prevalence of olfactory and gustatory dysfunction in COVID-19. However, the severity of and recovery from these symptoms have no correlations with the viral load of SARS-CoV-2. Level of Evidence 4Laryngoscope, 2020

An 80-year-old woman presented to our hospital with mild headache in November 2015. She had a history of hypertension, diabetes mellitus, and hyperlipidaemia. She was febrile (38.6°C) but did not appear septic. Abdominal examination revealed mild splenomegaly but no hepatomegaly and there were no focal neurological signs or suggestions of other organ involvement. A full blood count showed leukocytes 124.0 × 109/L (neutrophils 120.3 × 109/L, lymphocytes 2.5 × 109/L, monocytes 1.2 × 109/L); haemoglobin 7.8 g/dL, mean corpuscular volume 89.1 fL; and platelets 384 × 109/L. The blood film showed marked neutrophilia, occasional myelocytes, and absolute basophilia but no blasts. The neutrophils showed toxic granules and were not dysplastic (Fig 1). Plain radiographs of the chest, kidney, ureter, and urinary bladder did not reveal any abnormalities. Bacterial cultures of the blood and urine did not reveal any septic foci. Because of the marked neutrophilia, the patient was initially treated for bacterial sepsis with empirical intravenous amoxicillin with clavulanic acid. Subsequent ultrasonography of the abdomen Hong Kong Med J 2019;25:248–50 https://doi.org/10.12809/hkmj176959

We report the first case of neonatal alloimmune thrombocytopenia (NAIT) secondary to anti-HLA antibody in Hong Kong. The baby girl was born at 39 weeks gestation by spontaneous delivery, with a birth weight at 4.165 kg. She was kept in hospital for investigations of large for gestational age. A full blood count incidentally showed: moderate thrombocytopenia (Platelets, 64 × 109/L), but normal leukocyte count and haemoglobin. No red cell fragments or spherocytes nor platelet clumps were noted. Over the next two days, her platelet count dropped to 8.0 × 109/L on Day 2, but there were no major bleeding. Her and her mother's blood groups were both B + and direct antiglobulin test was negative. Antibody screen was negative on the maternal serum. Her mother did not have thrombocytopenia. In view of her marked thrombocytopenia, she was transfused one unit of random donor group B + platelet concentrate and IVIG 4.2 g, and the platelet count rose to 98 × 109/L on Day 3. The mother had no history of blood transfusion. No anti-HPA antibodies were detected by antigen-captured ELISA. Maternal serum was crossmatch incompatible with father's platelets by PIFT. Luminex SAB test demonstrated broad spectrum anti-HLA IgG antibodies with 2,000–5,000 MFI against several HLA-A, -B antigens in the maternal serum, and NAIT caused by HLA antibodies was suspected. Anti-A203 and anti-B55 IgG antibodies were found against the paternal inherited HLA antigens. These specific antibodies with 1,500–2,000 MFI were also detected in her pre-treatment serum. Although the initial platelet response was satisfactory, the platelet count gradually dropped again from 82 × 109/L on Day 4 to 49 × 109/L on Day 7. She was then given further IVIG 4.2 g with the platelet count rose to 79 × 109/L on Day 8. The platelet count then stabilized up to Day 10. Although the mother was a primipara, anti-HLA antibodies could still occur since even non-transfused men may have 'naturally occurring' anti-HLA antibodies. Based on the anti-HLA antibodies in the maternal serum, the mother's and baby's HLA typing results and the PIFT results, we believe that there is evidence this is a rare and unique case of NAIT secondary to anti-HLA antibodies.

Myeloproliferative neoplasms (MPNs) are a group of haematological malignancies that can be characterised by a somatic mutation (JAK2V617F). This mutation causes the bone marrow to produce excessive blood cells and is found in polycythaemia vera (~95%), essential thrombocythaemia and primary myelofibrosis (both ~50%). It is considered as a major genetic factor contributing to the development of these MPNs. No genetic association study of MPN in the Hong Kong population has so far been reported. Here, we investigated the relationship between germline JAK2 polymorphisms and MPNs in Hong Kong Chinese to find causal variants that contribute to MPN development. We analysed 19 tag single nucleotide polymorphisms (SNPs) within the JAK2 locus in 172 MPN patients and 470 healthy controls. Three of these 19 SNPs defined the reported JAK2 46/1 haplotype: rs10974944, rs12343867 and rs12340895. Allele and haplotype frequencies were compared between patients and controls by logistic regression adjusted for sex and age. Permutation test was used to correct for multiple comparisons. With significant findings from the 19 SNPs, we then examined 76 additional SNPs across the 148.7-kb region of JAK2 via imputation with the SNP data from the 1000 Genomes Project.

Platelet factor 4 (PF4) is an angiostatic chemokine that suppresses tumor growth and metastasis. We previously revealed frequent transcriptional silencing of PF4 in multiple myeloma, but the functional roles of this chemokine are still unknown. We studied the apoptotic effects of PF4 on myeloma cell lines and primary myeloma in vitro, and investigated the involved signaling pathway. The in vivo effects were also studied using a mouse model. PF4 not only suppressed myeloma-associated angiogenesis, but also inhibited growth and induced apoptosis in myeloma cells. We found that PF4 negatively regulated STAT3 and concordantly inhibited constitutive and interleukin-6-induced phosphorylation of STAT3, and down-regulated the expression of STAT3 target genes (Mcl-1, survivin and VEGF). Overexpression of constitutively activated STAT3 could rescue PF4-induced apoptotic effects. Furthermore, we found that PF4 induced the expression of SOCS3, a STAT3 inhibitor, and gene silencing of SOCS3 abolished its ability to inhibit STAT3 activation, suggesting a critical role of SOCS3 in PF4-induced STAT3 inhibition. Knockdown of LRP1, a putative PF4 receptor, could also abolish PF4-induced apoptosis and STAT3 inhibition. Finally, the tumor growth inhibitory effect of PF4 was confirmed by in vivo mouse models. Immunostaining of rabbit bone xenografts from PF4-treated mice showed induction of apoptosis of myeloma cells and inhibition of angiogenesis, which was associated with suppression of STAT3 activity. Together, our preclinical data indicate that PF4 may be a potential new targeting agent for the treatment of myeloma.

Abstract Abstract 3597 Background. The incidence of acute promyelocytic leukemia (APL) shows racial variations. Population based epidemiologic studies are feasible because of common diagnostic criteria and treatment. The prognosis of APL has substantially improved since the advent of all trans-retinoic acid (ATRA) and arsenic trioxide (As2O3). Material and methods. Data on survival and relapse of consecutive APL patients in Hong Kong from 1991 to 2011 were obtained from the Hong Kong Cancer Registry (with at least 98% reporting and complete follow-up), and verified by hospital records. Data were censored at the end of July 2011. Potential factors impacting on survival including age, platelet count (Plat), white blood cell count (WBC), gender; 5-year cohort and As2O3 maintenance were analyzed by logistic regression. Results. Four hundred and eight cases of APL (198 men, 210 women) at a median age of 41 (3–89) years were registered. There was a rise in cases number with successive 5-year cohorts, but the WHO standardized age incidence rate (WSIR) was unchanged (Table 1). At diagnosis (Dx), the median hemoglobin was 8.4 (2.9–14.9) g/dL, WBC 17.7 (0.3–250) × 109/L (>10 × 109/L in 129 cases) and Plat 35 (3–270) × 109/L (< 40 × 109/L in 282 cases). Early death (within 30 days of Dx) occurred in 88 cases. Complete remission (CR) was achieved in 318 cases. Outcome was unknown in 2 cases. The incidence of early death decreased progressively with each 5-year cohort (p=0.035), but was positively correlated with older age (p<0.001), high WBC (p<0.001) and male gender (trend only, p=0.06). From CR1, the median follow-up was 83 (0–249) months. Relapse occurred in 108 cases. The 5-year relapse rate fell from 54% (no maintenance) to 16% (p<0.001) with the adoption of ATRA (n=110) and oral As2O3 (n=88; since 2001) maintenance. Relapse rates were lower in patients receiving As2O3 than ATRA maintenance (17% versus 38%; p=0.008). Risk factors predicting relapse were older age (p=0.001), no oral-As2O3 maintenance (p=0.003), high WBC (p=0.023) and male gender (trend only, p=0.056). For relapsed patients, 5-year overall survival (OS) from CR1 was improved from 67% with ATRA (1993–1998) to 96% with oral-As2O3 (since 1999–2011) treatment. The causes of deaths after CR1 were APL relapse (n=35), second cancer (n=8), bone marrow transplantation (BMT, n=7), chemotherapy (n=3) and unrelated causes (n=6). Allogeneic BMT was not performed since 1999. For the last 5-year cohort (2006–2011), there were no APL related deaths after CR1. With reduction of induction death, and improvement in treatment and prevention of relapses, the 5-year OS from diagnosis increased from 44% for the first 5-year cohort to 80% for the last 5-year cohort. On multivariate analysis, age (p<0.001) and cohort period (p=0.031) were determinants of OS. Conclusions. Population based incidence data showed that APL in Hong Kong was more prevalent than the United States (0.15–0.18/100000/year). Oral-As2O3 has markedly changed the outcome of APL patients. Early death is now the greatest problem curtailing survival of APL patients. Disclosures: No relevant conflicts of interest to declare.

Haemoglobin (Hb) Bonn is a newly described benign Hb variant that causes falsely depressed oxygen saturation as measured by pulse oximetry. It was found to be associated with mild haemolysis. Since its first report in a German family, no further cases have been documented in the literature. We report the first Chinese family with this Hb variant and confirm its unusual clinical presentation. No evidence of haemolysis was seen. The absence of consistent abnormalities in routine Hb tests such as high-performance liquid chromatography and gel electrophoresis means that spurious hypoxaemia is the only clue to its presence, and genotypic analysis is the preferred method for definitive diagnosis. Its positive identification is important for counselling and will help to avoid unnecessary investigation and treatment for this benign condition.

A 68-year-old female presented with gum bleeding and multiple bruises. Peripheral blood counts showed pancytopenia: haemoglobin 71 g/l, platelet count 1·3 × 109/l and leucocytes 1·3 × 109/l with 15% neutrophils, 54% lymphocytes and 31% abnormal promyelocytes. The abnormal promyelocytes were heavily granulated and some had bilobed nuclei. Many faggot cells were found. The bone marrow was hypercellular and was packed with abnormal promyelocytes (top left). Cytochemical study showed that the abnormal promyelocytes were strongly positive for myeloperoxidase and chloroacetate esterase. Coagulation screening tests showed: prothrombin time 14·8 s (normal 10–12·2 s), activated partial thromboplastin time 27·1 s (normal 26·5–36·5 s) and D-dimer >400 ng/ml FEU (normal <200 ng/ml FEU). A provisional diagnosis of acute promyelocytic leukaemia was made. However, cytogenetic study performed by overnight fluorodeoxyuridine-synchronized culture of marrow cells showed 46,XX[20]. Reverse transcription polymerase chain reaction on RNA extracted from the marrow cells detected the PML-RARA fusion transcript, and DNA sequence analysis showed that the breakpoint in the PML gene was at the bcr1 in exon 6. Fluorescence in situ hybridization (FISH) with dual colour dual fusion probes (SpectrumOrange labelled PML and SpectrumGreen-labelled RARA) showed 46,XX.ish ins(17;15)(q21·1;q22)(RARA+,PML+). Nuclear FISH showed two orange PML, one green RARA and one yellow PML-RARA fusion signals (top right). Metaphase FISH shows a single PML-RARA fusion signal in chromosome 17, indicating insertion of the PML gene on 15q into the RARA gene on 17q (bottom). The diagnosis of acute promyelocytic leukaemia with cryptic PML-RARA was confirmed. The patient was treated with all-trans-retinoic acid. The t(15;17)(q22;q12) is detectable in only about 90% of APL with molecular evidence of PML-RARA fusion. In most instances, absence of the t(15;17) is a reflection of failed cytogenetic study, but about 2–3% of cases are due to cryptic PML-RARA fusion as a result of insertion of the PML gene into the RARA gene or vice versa, which is only demonstrable by FISH.

A 26-year-old mother (G1P1) presented with generalized lymphadenopathy 2 months after spontaneous vaginal delivery of a normal 3Æ5 kg daughter. A peripheral blood examination (haemoglobin 133 g/l, white cell count 4Æ2 · 10 /l, platelet count 183 · 10 /l) showed occasional blasts, and a marrow biopsy showed sheets of blasts (Fig 1A) that were negative for myeloperoxidase and non-specific esterase, but showed weak granular periodic acid-Schiff positivity. Flow cytometric immunophenotyping of the blasts showed expression of CD4, CD7, CD56 and HLA-DR, but negativity for Tdt, MPO, CD13, CD34 and other B and T cell markers (CD19, CD20, CD22 and CD2, CD3, CD5, CD8). Cytogenetics (Fig 1B) showed 44, XX, t(1;6)(q21;q23),)9,)13[5]/44,idem,t(9;17)(p22;p13)[3]/46XX[10]. She was treated as undifferentiated acute leukaemia with a lymphoid leukaemia protocol (Au et al, 1998) followed by allogeneic haemopoietic stem cell transplantation (HSCT) from an unrelated donor (two younger brothers were not a human leucocyte antigen (HLA) match) in first remission (conditioning: cyclophosphamide, total body irradiation). At 18 months of age, her infant daughter presented with recurrent fever and anaemia (haemoglobin 56 g/l, white cell count 5Æ5 · 10 /l, platelet count 393 · x10 /l). The peripheral film was unremarkable, but a marrow biopsy showed 14% granulated blasts and dysplastic megakaryocytes (Fig 1C), compatible with refractory anaemia with excess blasts, stage 2 (RAEB-2). Cytogenetic study showed 45, XX, )7[2]/46, XX[2]. Using a directly labelled chromosome 7 centromeric probe (D7Z1; Vysis, Downers Grove, IL, USA), monosomy 7 was shown in 58% of marrow nucleated cells (Fig 1D). Chromosome fragility screening using diepoxybutane-induced chromosome breakage was negative, but sequencing for RUNX1 mutation was not performed. The peripheral count was static for 6 weeks and the child underwent direct HSCT from another unrelated donor (conditioning: bulsuphan, cyclophasmide, melphalan, antithymocyte globulin). Both patients remained well at 2 and 1-year follow-up respectively. They denied any herbal or toxin exposure, nor any family history of leukaemia or malignancies; and neither patient had any dysmorphic features.

Background Chemokines play important roles in inflammation and antiviral action. We examined whether polymorphisms of RANTES, IP-10 and Mig affect the susceptibility to and outcome of severe acute respiratory syndrome (SARS). Methods We tested the polymorphisms of RANTES, IP-10 and Mig for their associations with SARS in 495 Hong Kong Chinese SARS patients and 578 controls. Then we tried to confirm the results in 356 Beijing Chinese SARS patients and 367 controls. Results RANTES -28 G allele was associated with SARS susceptibility in Hong Kong Chinese ( P < 0.0001, OR = 2.80, 95%CI:2.11–3.71). Individuals with RANTES -28 CG and GG genotypes had a 3.28-fold (95%CI:2.32–4.64) and 3.06-fold (95%CI:1.47–6.39) increased risk of developing SARS respectively ( P < 0.0001). This -28 G allele conferred risk of death in a gene-dosage dependent manner ( P = 0.014) with CG and GG individuals having a 2.12-fold (95% CI: 1.11–4.06) and 4.01-fold (95% CI: 1.30–12.4) increased risk. For the replication of RANTES data in Beijing Chinese, the -28 G allele was not associated with susceptibility to SARS. However, -28 CG (OR = 4.27, 95%CI:1.64–11.1) and GG (OR = 3.34, 95%CI:0.37–30.7) were associated with admission to intensive care units or death due to SARS ( P = 0.011). Conclusion RANTES -28 G allele plays a role in the pathogenesis of SARS.

Background Host genetic factors are important determinants in tuberculosis (TB). The SLC11A1 (or NRAMP1 ) gene has been studied extensively for genetic association with TB, but with inconsistent findings. In addition, no study has yet looked into the effect of sex and age on the relationship between SLC11A1 polymorphisms and TB. Methods A case-control study was conducted. In total, 278 pulmonary TB patients and 282 sex- and age-matched controls without TB were recruited. All subjects were ethnic Chinese. On the basis of linkage disequilibrium pattern, three genetic markers from SLC11A1 and one from the nearby IL8RB locus were selected and examined for association with TB susceptibility. These markers were genotyped using single strand conformation polymorphism analysis or fragment analysis of amplified products. Results Statistically significant differences in allele ( P = 0.0165, OR = 1.51) and genotype ( P = 0.0163, OR = 1.59) frequencies of the linked markers SLC6a/b (classically called D543N and 3'UTR) of the SLC11A1 locus were found between patients and controls. With stratification by sex, positive associations were identified in the female group for both allele ( P = 0.0049, OR = 2.54) and genotype ( P = 0.0075, OR = 2.74) frequencies. With stratification by age, positive associations were demonstrated in the young age group (age ≤65 years) for both allele ( P = 0.0047, OR = 2.52) and genotype ( P = 0.0031, OR = 2.92) frequencies. All positive findings remained significant even after correction for multiple comparisons. No significant differences were noted in either the male group or the older age group. No significant differences were found for the other markers (one SLC11A1 marker and one IL8RB marker) either. Conclusion This study confirmed the association between SLC11A1 and TB susceptibility and demonstrated for the first time that the association was restricted to females and the young age group.

AbstractGenetic polymorphisms have been demonstrated to be associated with vulnerability to human infection. ICAM3, an intercellular adhesion molecule important for T cell activation, and FCER2 (CD23), an immune response gene, both located on chromosome 19p13.3 were investigated for host genetic susceptibility and association with clinical outcome. A case-control study based on 817 patients with confirmed severe acute respiratory syndrome (SARS), 307 health care worker control subjects, 290 outpatient control subjects, and 309 household control subjects unaffected by SARS from Hong Kong was conducted to test for genetic association. No significant association to susceptibility to SARS-CoV infection was found for the FCER2 and the ICAM3 single nucleotide polymorphisms. However, patients with SARS homozygous for ICAM3 Gly143 showed significant association with higher lactate dehydrogenase levels (P=.0067; odds ratio [OR], 4.31 [95% confidence interval [CI], 1.37–13.56]) and lower total white blood cell counts (P=.022; OR, 0.30 [95% CI, 0.10–0.89]) on admission. These findings support the role of ICAM3 in the immunopathogenesis of SARS.

Background: Cytokines play important roles in antiviral action. We examined whether polymorphisms of IFN- γ , TNF- α and IL-10 affect the susceptibility to and outcome of severe acute respiratory syndrome (SARS). Methods: A case-control study was carried out in 476 Chinese SARS patients and 449 healthy controls. We tested the polymorphisms of IFN- γ , TNF- α and IL-10 for their associations with SARS. Results: IFN- γ +874A allele was associated with susceptibility to SARS in a dose-dependent manner ( P < 0.001). Individuals with IFN- γ +874 AA and AT genotype had a 5.19-fold (95% Confidence Interval [CI], 2.78-9.68) and 2.57-fold (95% CI, 1.35-4.88) increased risk of developing SARS respectively. The polymorphisms of IL-10 and TNF- α were not associated with SARS susceptibility. Conclusion: IFN- γ +874A allele was shown to be a risk factor in SARS susceptibility.

We report the first case of Hb Phnom Penh where a molecular study was done on the patient's sample. The result confirmed the predicted DNA sequence change involved in the mutation, which was delineated by another group in 1998 using amino acid analysis.