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"Johnson, Peter W. M."
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S-adenosylhomocysteine hydrolase inhibition by 3-deazaneplanocin A analogues induces anti-cancer effects in breast cancer cell lines and synergy with both histone deacetylase and HER2 inhibition
by
Packham, Graham
,
Hayden, Annette
,
Crabb, Simon J.
in
Adenosine - analogs & derivatives
,
Adenosine - chemistry
,
Adenosine - pharmacology
2011
Epigenetic abnormalities including abnormal histone methyltransferase activity contribute to breast cancer pathogenesis. An example is over expression of the polycomb repressive complex (PRC) 2 member enhancer of zeste homolog 2 (EZH2) which is linked to epigenetic silencing and poor prognosis. Recent evidence shows that S-adenosylhomocysteine (AdoHcy) hydrolase inhibitors (AHI) such as 3-deazaneplanocin A (DZNep) modulate chromatin through indirect inhibition of histone methyltransferases including EZH2. We investigated the biological effects of AdoHcy hydrolase inhibition using DZNep and its structural analogues 3-deazaadenosine (DZA) and neplanocin A (Nep A) in breast cancer cells. EZH2 protein expression was decreased and dose dependent growth inhibition occurred with variable potencies in MCF7, MDA-MB-231 and SKBr3 breast cancer cells. Cellular proliferation was inhibited through G
2
/M cell cycle arrest and apoptosis. In addition breast cancer cells accumulated cytoplasmic lipid droplets in response to AdoHcy hydrolase inhibition consistent with a differentiating effect. Each analogue induced a similar pattern of biological activity against breast cancer cells but with differences in potency (DZA > DZNep > Nep A). Co-administration with the histone deacetylase (HDAC) inhibitor trichostatin A (TSA) induced synergistic inhibition of breast cancer cell proliferation. Furthermore, the relatively AHI resistant human epidermal growth factor receptor 2 (HER2) positive cell line SKBr3 underwent synergistic growth inhibition in response to co-treatment with the HER2 directed therapeutic antibody trastuzumab. In conclusion, AHI induce growth inhibition, cell cycle arrest, apoptosis and differentiation in breast cancer cells and synergise with HDAC and HER2 inhibition. Targeting histone methyltransferase activity might be of therapeutic value in breast cancer.
Journal Article
Risk prediction of covid-19 related death and hospital admission in adults after covid-19 vaccination: national prospective cohort study
2021
AbstractObjectivesTo derive and validate risk prediction algorithms to estimate the risk of covid-19 related mortality and hospital admission in UK adults after one or two doses of covid-19 vaccination.DesignProspective, population based cohort study using the QResearch database linked to data on covid-19 vaccination, SARS-CoV-2 results, hospital admissions, systemic anticancer treatment, radiotherapy, and the national death and cancer registries.SettingsAdults aged 19-100 years with one or two doses of covid-19 vaccination between 8 December 2020 and 15 June 2021.Main outcome measuresPrimary outcome was covid-19 related death. Secondary outcome was covid-19 related hospital admission. Outcomes were assessed from 14 days after each vaccination dose. Models were fitted in the derivation cohort to derive risk equations using a range of predictor variables. Performance was evaluated in a separate validation cohort of general practices.ResultsOf 6 952 440 vaccinated patients in the derivation cohort, 5 150 310 (74.1%) had two vaccine doses. Of 2031 covid-19 deaths and 1929 covid-19 hospital admissions, 81 deaths (4.0%) and 71 admissions (3.7%) occurred 14 days or more after the second vaccine dose. The risk algorithms included age, sex, ethnic origin, deprivation, body mass index, a range of comorbidities, and SARS-CoV-2 infection rate. Incidence of covid-19 mortality increased with age and deprivation, male sex, and Indian and Pakistani ethnic origin. Cause specific hazard ratios were highest for patients with Down’s syndrome (12.7-fold increase), kidney transplantation (8.1-fold), sickle cell disease (7.7-fold), care home residency (4.1-fold), chemotherapy (4.3-fold), HIV/AIDS (3.3-fold), liver cirrhosis (3.0-fold), neurological conditions (2.6-fold), recent bone marrow transplantation or a solid organ transplantation ever (2.5-fold), dementia (2.2-fold), and Parkinson’s disease (2.2-fold). Other conditions with increased risk (ranging from 1.2-fold to 2.0-fold increases) included chronic kidney disease, blood cancer, epilepsy, chronic obstructive pulmonary disease, coronary heart disease, stroke, atrial fibrillation, heart failure, thromboembolism, peripheral vascular disease, and type 2 diabetes. A similar pattern of associations was seen for covid-19 related hospital admissions. No evidence indicated that associations differed after the second dose, although absolute risks were reduced. The risk algorithm explained 74.1% (95% confidence interval 71.1% to 77.0%) of the variation in time to covid-19 death in the validation cohort. Discrimination was high, with a D statistic of 3.46 (95% confidence interval 3.19 to 3.73) and C statistic of 92.5. Performance was similar after each vaccine dose. In the top 5% of patients with the highest predicted covid-19 mortality risk, sensitivity for identifying covid-19 deaths within 70 days was 78.7%.ConclusionThis population based risk algorithm performed well showing high levels of discrimination for identifying those patients at highest risk of covid-19 related death and hospital admission after vaccination.
Journal Article
Prognostic significance of crown-like structures to trastuzumab response in patients with primary invasive HER2 + breast carcinoma
2022
Obesity can initiate, promote, and maintain systemic inflammation via metabolic reprogramming of macrophages that encircle adipocytes, termed crown-like structures (CLS). In breast cancer the presence of CLS has been correlated to high body mass index (BMI), larger mammary adipocyte size and postmenopausal status. However, the prognostic significance of CLS in HER2 + breast cancer is still unknown. We investigated the prognostic significance of CLS in a cohort of 69 trastuzumab-naïve and 117 adjuvant trastuzumab-treated patients with primary HER2 + breast cancer. Immunohistochemistry of tumour blocks was performed for CLS and correlated to clinical outcomes. CLS were more commonly found at the adipose-tumour border (B-CLS) (64.8% of patients). The presence of multiple B-CLS was associated with reduced time to metastatic disease (TMD) in trastuzumab treated patients with BMI ≥ 25 kg/m
2
but not those with BMI < 25 kg/m
2
. Phenotypic analysis showed the presence of CD32B + B-CLS was strongly correlated to BMI ≥ 25 kg/m
2
and reduced TMD in trastuzumab treated patients. Multivariable analysis suggested that CD32B + B-CLS positive tumours are associated with shorter TMD in trastuzumab-treated patients (HR 4.2 [95%CI, (1.01–17.4). This study indicates adipose-tumour border crown-like structures that are CD32B + potentially represent a biomarker for improved personalisation of treatment in HER2-overexpressed breast cancer patients.
Journal Article
Distinct genetic changes reveal evolutionary history and heterogeneous molecular grade of DLBCL with MYC/BCL2 double-hit
by
Clipson, Alexandra
,
Chen, Zi
,
Westhead, David R
in
Amino acids
,
B-cell lymphoma
,
Burkitt's lymphoma
2020
Using a Burkitt lymphoma-like gene expression signature, we recently defined a high-risk molecular high-grade (MHG) group mainly within germinal centre B-cell like diffuse large B-cell lymphomas (GCB-DLBCL), which was enriched for MYC/BCL2 double-hit (MYC/BCL2-DH). The genetic basis underlying MHG-DLBCL and their aggressive clinical behaviour remain unknown. We investigated 697 cases of DLBCL, particularly those with MYC/BCL2-DH (n = 62) by targeted sequencing and gene expression profiling. We showed that DLBCL with MYC/BCL2-DH, and those with BCL2 translocation, harbour the characteristic mutation signatures that are associated with follicular lymphoma and its high-grade transformation. We identified frequent MYC hotspot mutations that affect the phosphorylation site (T58) and its adjacent amino acids, which are important for MYC protein degradation. These MYC mutations were seen in a subset of cases with MYC translocation, but predominantly in those of MHG. The mutations were more frequent in double-hit lymphomas with IG as the MYC translocation partner, and were associated with higher MYC protein expression and poor patient survival. DLBCL with MYC/BCL2-DH and those with BCL2 translocation alone are most likely derived from follicular lymphoma or its precursor lesion, and acquisition of MYC pathogenic mutations may augment MYC function, resulting in aggressive clinical behaviour.
Journal Article
Non-IG::MYC in diffuse large B-cell lymphoma confers variable genomic configurations and MYC transactivation potential
by
Tooze, Reuben
,
Chen, Zi
,
Makker, Jasmine
in
14/32
,
631/67/68
,
692/699/1541/1990/291/1621/1915
2024
MYC
translocation occurs in 8–14% of diffuse large B-cell lymphoma (DLBCL), and may concur with
BCL2
and/or
BCL6
translocation, known as double-hit (DH) or triple-hit (TH). DLBCL-
MYC
/
BCL2
-DH/TH are largely germinal centre B-cell like subtype, but show variable clinical outcome, with
IG
::
MYC
fusion significantly associated with inferior survival. While DLBCL-
MYC
/
BCL6
-DH are variable in their cell-of-origin subtypes and clinical outcome. Intriguingly, only 40-50% of DLBCL with
MYC
translocation show high MYC protein expression (>70%). We studied 186 DLBCLs with
MYC
translocation including 32
MYC/BCL2/BCL6
-TH
, 75 MYC/BCL2
-DH and 26
MYC/BCL6
-DH. FISH revealed a
MYC
/
BCL6
fusion in 59% of DLBCL-
MYC/BCL2/BCL6
-TH and 27% of DLBCL-
MYC
/
BCL6
-DH. Targeted NGS showed a similar mutation profile and LymphGen genetic subtype between DLBCL-
MYC/BCL2/BCL6
-TH and DLBCL-
MYC/BCL2
-DH, but variable LymphGen subtypes among DLBCL-
MYC
/
BCL6
-DH. MYC protein expression is uniformly high in DLBCL with
IG::MYC
, but variable in those with non-
IG::MYC
including
MYC
/
BCL6
-fusion. Translocation breakpoint analyses of 8 cases by TLC-based NGS showed no obvious genomic configuration that enables
MYC
transactivation in 3 of the 4 cases with non-
IG:
:
MYC
, while a typical promoter substitution or
IGH
super enhancer juxtaposition in the remaining cases. The findings potentially explain variable MYC expression in DLBCL with
MYC
translocation, and also bear practical implications in its routine assessment.
Journal Article
RIVA – a phase IIa study of rituximab and varlilumab in relapsed or refractory B-cell malignancies: study protocol for a randomized controlled trial
by
Fines, Keira
,
Lim, Sean H.
,
Griffiths, Gareth
in
Antibodies
,
Antibodies, Monoclonal - administration & dosage
,
Antibodies, Monoclonal - adverse effects
2018
Background
Over 12,000 new cases of B-cell malignancies are diagnosed in the UK each year, with diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma (FL) being the most common subtypes. Standard frontline therapy consists of immunochemotherapy with a CD20 monoclonal antibody (mAb), such as rituximab, delivered in combination with multi-agent chemotherapy. Despite being considered a treatable and potentially curable cancer, approximately 30% of DLBCL cases will relapse after frontline therapy. Advanced stage FL is incurable and typically has a relapsing and remitting course with a frequent need for re-treatment
.
Based on supportive preclinical data, we hypothesised that the addition of varlilumab (an anti-CD27 mAb) to rituximab (an anti-CD20 mAb) can improve the rate, depth and duration of the response of rituximab monotherapy in patients with relapsed or refractory B-cell malignancies.
Methods/design
Combination treatment of varlilumab plus rituximab, in two different dosing regimens, is being tested in the RIVA trial. RIVA is a two-stage open-label randomised phase IIa design in up to 40 patients with low- or high-grade relapsed or refractory CD20
+
B-cell lymphoma. The study is open to recruitment in the UK. Enrolled patients are randomised 1:1 to two different experimental varlilumab to rituximab combinations.
The primary objective is to determine the safety and tolerability of the combination and the anti-tumour activity (response) in relapsed or refractory B-cell malignancies. Secondary objectives will include an evaluation of the duration of the response and overall survival. Tertiary translational objectives include assessment of B-cell depletion, changes in immune effector cell populations, expression of CD27 as a biomarker of response and pharmacokinetic properties. Analyses will not be powered for formal statistical comparisons between treatment arms.
Discussion
RIVA will determine whether the combination of rituximab and varlilumab in relapsed or refractory B-cell malignancies is active and safe prior to future phase II/III trials.
Trial registration
EudraCT, 2017–000302-37. Registered on 16 January 2017. ISRCTN,
ISRCTN15025004
. Registered on 16 August 2017.
Journal Article
XPO1 inhibition sensitises CLL cells to NK cell mediated cytotoxicity and overcomes HLA-E expression
2023
The first-in-class inhibitor of exportin-1 (XPO1) selinexor is currently under clinical investigation in combination with the BTK inhibitor ibrutinib for patients with chronic lymphocytic leukaemia (CLL) or non-Hodgkin lymphoma. Selinexor induces apoptosis of tumour cells through nuclear retention of tumour suppressor proteins and has also recently been described to modulate natural killer (NK) cell and T cell cytotoxicity against lymphoma cells. Here, we demonstrate that XPO1 inhibition enhances NK cell effector function against primary CLL cells via downregulation of HLA-E and upregulation of TRAIL death receptors DR4 and DR5. Furthermore, selinexor potentiates NK cell activation against CLL cells in combination with several approved treatments; acalabrutinib, rituximab and obinutuzumab. We further demonstrate that lymph node associated signals (IL-4 + CD40L) inhibit NK cell activation against CLL cells via upregulation of HLA-E, and that inhibition of XPO1 can overcome this protective effect. These findings allow for the design of more efficacious combination strategies to harness NK cell effector functions against CLL.
Journal Article
Obesity Is Associated with Immunometabolic Changes in Adipose Tissue That May Drive Treatment Resistance in Breast Cancer: Immune-Metabolic Reprogramming and Novel Therapeutic Strategies
by
Copson, Ellen
,
Beers, Stephen A.
,
Savva, Constantinos
in
1-Phosphatidylinositol 3-kinase
,
Adaptive immunity
,
Adipocytes
2023
White adipose tissue (WAT) represents an endocrinologically and immunologically active tissue whose primary role is energy storage and homeostasis. Breast WAT is involved in the secretion of hormones and proinflammatory molecules that are associated with breast cancer development and progression. The role of adiposity and systemic inflammation in immune responses and resistance to anti-cancer treatment in breast cancer (BC) patients is still not clear. Metformin has demonstrated antitumorigenic properties both in pre-clinical and clinical studies. Nevertheless, its immunomodulating properties in BC are largely unknown. This review aims to evaluate the emerging evidence on the crosstalk between adiposity and the immune-tumour microenvironment in BC, its progression and treatment resistance, and the immunometabolic role of metformin in BC. Adiposity, and by extension subclinical inflammation, are associated with metabolic dysfunction and changes in the immune-tumour microenvironment in BC. In oestrogen receptor positive (ER+) breast tumours, it is proposed that these changes are mediated via a paracrine interaction between macrophages and preadipocytes, leading to elevated aromatase expression and secretion of pro-inflammatory cytokines and adipokines in the breast tissue in patients who are obese or overweight. In HER2+ breast tumours, WAT inflammation has been shown to be associated with resistance to trastuzumab mediated via MAPK or PI3K pathways. Furthermore, adipose tissue in patients with obesity is associated with upregulation of immune checkpoints on T-cells that is partially mediated via immunomodulatory effects of leptin and has been paradoxically associated with improved responses to immunotherapy in several cancers. Metformin may play a role in the metabolic reprogramming of tumour-infiltrating immune cells that are dysregulated by systemic inflammation. In conclusion, evidence suggests that body composition and metabolic status are associated with patient outcomes. To optimise patient stratification and personalisation of treatment, prospective studies are required to evaluate the role of body composition and metabolic parameters in metabolic immune reprogramming with and without immunotherapy in patients with BC.
Journal Article
Epigenetics of Indolent Lymphoma and How It Drives Novel Therapeutic Approaches—Focus on EZH2-Targeted Drugs
2021
Purpose of ReviewEpigenetic modifier gene mutations are common in patients with follicular lymphoma. Here we review the pathogenesis of these mutations and how they are targeted by epigenetic drugs including EZH2 inhibitors in both mutated and wild-type disease.Recent FindingsThe use of EZH2 inhibitor tazematostat in early phase clinical trials has proved encouraging in the treatment of follicular lymphoma harbouring an EZH2 mutation; however, responses are also seen in patients with wild-type disease which is partially explained by the off target effects of EZH2 inhibition on immune cells within the tumour microenvironment.SummaryFurther studies incorporating prospective molecular profiling are needed to allow stratification of patients at both diagnosis and relapse to further our understanding of how epigenetic modifier mutations evolve over time. The use of tazematostat in combination or upfront in patients with an EZH2 mutation remains unanswered; however, given durable responses, ease of oral administration, and tolerability, it is certainly an attractive option.
Journal Article
Immune responses against SARS-CoV-2 variants after two and three doses of vaccine in B-cell malignancies: UK PROSECO study
by
Coleman, Helen
,
Kelly, Adam
,
Galloway, Celine
in
Antibodies
,
Antibody Formation
,
Chemotherapy
2022
Patients with hematological malignancies are at increased risk of severe COVID-19 outcomes due to compromised immune responses, but the insights of these studies have been compromised due to intrinsic limitations in study design. Here we present the PROSECO prospective observational study ( NCT04858568 ) on 457 patients with lymphoma that received two or three COVID-19 vaccine doses. We show undetectable humoral responses following two vaccine doses in 52% of patients undergoing active anticancer treatment. Moreover, 60% of patients on anti-CD20 therapy had undetectable antibodies following full vaccination within 12 months of receiving their anticancer therapy. However, 70% of individuals with indolent B-cell lymphoma displayed improved antibody responses following booster vaccination. Notably, 63% of all patients displayed antigen-specific T-cell responses, which increased after a third dose irrespective of their cancer treatment status. Our results emphasize the urgency of careful monitoring of COVID-19-specific immune responses to guide vaccination schemes in these vulnerable populations.
Journal Article