MerTK Drives Proliferation and Metastatic Potential in Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is characterized by the absence of the estrogen receptor, progesterone receptor, and receptor tyrosine kinase HER2 expression. Due to the limited number of FDA-approved targeted therapies for TNBC, there is an ongoing need to understand the molecular underpinnings of TNBC for the development of novel combinatorial treatment strategies. This study evaluated the role of the MerTK receptor tyrosine kinase on proliferation and invasion/metastatic potential in TNBC. Immunohistochemical analysis demonstrated MerTK expression in 58% of patient-derived TNBC xenografts. The stable overexpression of MerTK in human TNBC cell lines induced an increase in proliferation rates, robust in vivo tumor growth, heightened migration/invasion potential, and enhanced lung metastases. NanoString nCounter analysis of MerTK-overexpressing SUM102 cells (SUM102-MerTK) revealed upregulation of several signaling pathways, which ultimately drive cell cycle progression, reduce apoptosis, and enhance cell survival. Proteomic profiling indicated increased endoglin (ENG) production in SUM102-MerTK clones, suggesting that MerTK creates a conducive environment for increased proliferative and metastatic activity via elevated ENG expression. To determine ENG's role in increasing proliferation and/or metastatic potential, we knocked out ENG in a SUM102-MerTK clone with CRISPR technology. Although this ENG knockout clone exhibited similar in vivo growth to the parental SUM102-MerTK clone, lung metastasis numbers were significantly decreased ~4-fold, indicating that MerTK enhances invasion and metastasis through ENG. Our data suggest that MerTK regulates a unique proliferative signature in TNBC, promoting robust tumor growth and increased metastatic potential through ENG upregulation. Targeting MerTK and ENG simultaneously may provide a novel therapeutic approach for TNBC patients.

Randomized Bendamustine-Rituximab(R) + Bortezomib Induction and R + Lenalidomide Maintenance for Mantle Cell Lymphoma.

While initial therapy of mantle cell lymphoma (MCL) is not standardized, bendamustine-rituximab (BR) is commonly used in older patients. Rituximab (R) maintenance following induction is often utilized. Thus, the open-label, randomized phase II ECOG-ACRIN Cancer Research Group E1411 trial was designed to test two questions: 1) Does addition of bortezomib to BR induction (BVR) and/or 2) addition of lenalidomide to rituximab (LR) maintenance improve progression-free survival (PFS) in patients with treatment-naïve MCL? From 2012-2016, 373 previously untreated patients, 87% ≥ 60 years old, were enrolled in this trial. At a median follow up of 7.5 years, there is no difference in the median PFS of BR compared to BVR (5.5 yrs vs. 6.4 yrs, HR 0.90, 90% CI 0.70, 1.16). There were no unexpected additional toxicities with BVR treatment compared to BR, with no impact on total dose/duration of treatment received. Independent of the induction treatment, addition of lenalidomide to rituximab did not significantly improve PFS, with median PFS in R vs LR (5.9 yrs vs 7.2 yrs, HR 0.84 90% CI 0.62, 1.15). The majority of patients completed the planned 24 cycles of LR at the scheduled dose. In summary, adding bortezomib to BR induction does not prolong PFS in treatment-naïve MCL, and LR maintenance was not associated with longer PFS compared with rituximab alone following BR. Nonetheless, the > 5 year median PFS outcomes in this prospective cooperative group trial indicate the efficacy of BR followed by rituximab maintenance as highly effective initial therapy for older MCL patients. (NCT01415752).

Epithelial ingrowth in descemet membrane endothelial keratoplasty associated with vitreous loss.

BACKGROUND: Epithelial ingrowth is a rare but potentially sight-threatening complication caused by the invasion of corneal or conjunctival epithelial cells into the eye during ocular surgeries. DMEK is emerging as a widely used surgery for endothelial keratoplasty with its improved safety profile. We describe a case of epithelial ingrowth in the graft-host interface after uneventful DMEK associated with vitreous prolapse in the anterior chamber. CASE PRESENTATION: An 81-year-old female with Fuchs endothelial dystrophy underwent DMEK for corneal decompensation following cataract surgery. During the DMEK procedure, vitreous prolapse was observed around the intraocular lens (IOL). Her early postoperative course was unremarkable, but a dense paracentral interface opacity was observed during the 3-month follow-up. The area of epithelial ingrowth was imaged with optical coherence tomography (OCT) as a uniform nodule with a discrete increase in interface hyperreflectivity. A low-energy YAG laser was applied to remove the opacity. She maintained good vision and clear cornea without reoccurrence after treatment. CONCLUSIONS: We propose that, in addition to the introduction of epithelial cells during surgery, vitreous retention in the anterior chamber may be a risk factor by providing a scaffold that potentially aggravates epithelial ingrowth in DMEK. Our case demonstrated that early YAG intervention may disrupt interface epithelial cell growth, and the transmitted laser energy may fragment the scaffold vitreous noninvasively.

Chronic Myeloid Leukemia, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology.

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome resulting from a reciprocal translocation between chromosomes 9 and 22 [t9;22] that gives rise to a BCR::ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase in developed countries. Tyrosine kinase inhibitor (TKI) therapy is a highly effective treatment option for patients with chronic phase-CML. The primary goal of TKI therapy in patients with chronic phase-CML is to prevent disease progression to accelerated phase-CML or blast phase-CML. Discontinuation of TKI therapy with careful monitoring is feasible in selected patients. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase-CML.

Recent Advances in Imaging Macular Atrophy for Late-Stage Age-Related Macular Degeneration.

Age-related macular degeneration (AMD) is a leading cause of blindness worldwide. In late-stage AMD, geographic atrophy (GA) of dry AMD or choroidal neovascularization (CNV) of neovascular AMD eventually results in macular atrophy (MA), leading to significant visual loss. Despite the development of innovative therapies, there are currently no established effective treatments for MA. As a result, early detection of MA is critical in identifying later central macular involvement throughout time. Accurate and early diagnosis is achieved through a combination of clinical examination and imaging techniques. Our review of the literature depicts advances in retinal imaging to identify biomarkers of progression and risk factors for late AMD. Imaging methods like fundus photography; dye-based angiography; fundus autofluorescence (FAF); near-infrared reflectance (NIR); optical coherence tomography (OCT); and optical coherence tomography angiography (OCTA) can be used to detect and monitor the progression of retinal atrophy. These evolving diverse imaging modalities optimize detection of pathologic anatomy and measurement of visual function; they may also contribute to the understanding of underlying mechanistic pathways, particularly the underlying MA changes in late AMD.

A gain-of-function p53 mutant synergizes with oncogenic NRAS to promote acute myeloid leukemia in mice.

We previously demonstrated that a subset of acute myeloid leukemia (AML) patients with concurrent RAS pathway and TP53 mutations have an extremely poor prognosis and that most of these TP53 mutations are missense mutations. Here, we report that, in contrast to the mixed AML and T cell malignancy that developed in NrasG12D/+ p53-/- (NP-/-) mice, NrasG12D/+ p53R172H/+ (NPmut) mice rapidly developed inflammation-associated AML. Under the inflammatory conditions, NPmut hematopoietic stem and progenitor cells (HSPCs) displayed imbalanced myelopoiesis and lymphopoiesis and mostly normal cell proliferation despite MEK/ERK hyperactivation. RNA-Seq analysis revealed that oncogenic NRAS signaling and mutant p53 synergized to establish an NPmut-AML transcriptome distinct from that of NP-/- cells. The NPmut-AML transcriptome showed GATA2 downregulation and elevated the expression of inflammatory genes, including those linked to NF-κB signaling. NF-κB was also upregulated in human NRAS TP53 AML. Exogenous expression of GATA2 in human NPmut KY821 AML cells downregulated inflammatory gene expression. Mouse and human NPmut AML cells were sensitive to MEK and NF-κB inhibition in vitro. The proteasome inhibitor bortezomib stabilized the NF-κB-inhibitory protein IκBα, reduced inflammatory gene expression, and potentiated the survival benefit of a MEK inhibitor in NPmut mice. Our study demonstrates that a p53 structural mutant synergized with oncogenic NRAS to promote AML through mechanisms distinct from p53 loss.

EGR1 Addiction in Diffuse Large B-cell Lymphoma.

Early growth response gene (EGR1) is a transcription factor known to be a downstream effector of B-cell receptor signaling and Janus kinase 1 (JAK1) signaling in diffuse large B-cell lymphoma (DLBCL). While EGR1 is characterized as a tumor suppressor in leukemia and multiple myeloma, the role of EGR1 in lymphoma is unknown. Here we demonstrate that EGR1 is a potential oncogene that promotes cell proliferation in DLBCL. IHC analysis revealed that EGR1 expression is elevated in DLBCL compared with normal lymphoid tissues and the level of EGR1 expression is higher in activated B cell-like subtype (ABC) than germinal center B cell-like subtype (GCB). EGR1 expression is required for the survival and proliferation of DLBCL cells. Genomic analyses demonstrated that EGR1 upregulates expression of MYC and E2F pathway genes through the CBP/p300/H3K27ac/BRD4 axis while repressing expression of the type I IFN pathway genes by interaction with the corepressor NAB2. Genetic and pharmacologic inhibition of EGR1 synergizes with the BRD4 inhibitor JQ1 or the type I IFN inducer lenalidomide in growth inhibition of ABC DLBCL both in cell cultures and xenograft mouse models. Therefore, targeting oncogenic EGR1 signaling represents a potential new targeted therapeutic strategy in DLBCL, especially for the more aggressive ABC DLBCL. IMPLICATIONS: The study characterizes EGR1 as a potential oncogene that promotes cell proliferation and defines EGR1 as a new molecular target in DLBCL, the most common non-Hodgkin lymphoma.

Diagnostic challenges in an aggressive case of peripheralizing marginal zone lymphoma.

B-cell lymphomas with atypical presentation or immunophenotype pose diagnostic challenges. Conventional ancillary tests (cytogenetics, FISH) can help, but have technical limitations. New technologies such as mate-pair sequencing (MPSeq) offer a route around these technical limitations.

Chronic Myeloid Leukemia, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology.

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome (Ph) which results from a reciprocal translocation between chromosomes 9 and 22 [t(9;22] that gives rise to a BCR-ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase. Tyrosine kinase inhibitor therapy is a highly effective first-line treatment option for all patients with newly diagnosed chronic phase CML. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase CML.

Utilization and Results of Repeat SARS-CoV-2 RT-PCR Testing in a Presumptive Low Prevalence Population.

INTRODUCTION: Early reports have raised concerns regarding the clinical sensitivity of nasopharyngeal SARS-CoV-2 reverse transcriptase-polymerase chain reaction (RT-PCR) testing for patients with COVID-19 symptoms, which has led to requests for repeat testing at our institution. However, to our knowledge, there are no reports to date of the utilization or results of repeat testing to help guide this practice. METHODS: The authors searched the institutional laboratory information system for consecutive patients who were tested for SARS-CoV-2 by RT-PCR of a nasopharyngeal specimen over a 1-month period. Characteristics and results of patients who received a single or multiple tests were documented and analyzed. RESULTS: Six thousand three (6003) tests were performed on 5757 patients; 272 (4.7%) patients were positive based on their initial test results. Two hundred thirty-six (4%) patients were tested more than once, with 226 (96%) tested twice. The largest proportion of these patients (n=160, 71%) were those who had an initial negative test followed by a repeat test for persistent symptoms. This group included all 7 patients who had discordant positive results on their second test; the result concordance rate within this group was 96%. CONCLUSION: In a population of patients with a low positive rate for SARS-CoV-2 by nasopharyngeal RT-PCR testing, repeat nasopharyngeal testing of negative patients who have persistent symptoms still yields a negative result in 96% of the cases.

Autoimmune Lymphoproliferative Syndrome: An Overview.

Autoimmune lymphoproliferative syndrome (ALPS) is an inherited nonmalignant lymphoproliferative disorder characterized by heterozygous mutations within the first apoptosis signal receptor (FAS) signaling pathway. Defects in FAS-mediated apoptosis cause an expansion and accumulation of autoreactive CD4- and CD8- (double-negative) T cells, leading to cytopenias, splenomegaly, lymphadenopathy, autoimmune disorders, and a greatly increased lifetime risk of lymphoma. The differential diagnosis of ALPS includes infection, other inherited immunodeficiency disorders, primary and secondary autoimmune syndromes, and lymphoma. The most consistent pathologic feature is a florid paracortical expansion of double-negative T cells in lymph nodes. A presumptive clinical diagnosis can be made from symptoms and a constellation of laboratory test results. However, a definitive diagnosis requires ancillary testing and enables disease subclassification. Recognition of ALPS is critical, as treatment with immunosuppressive therapies can effectively reduce or ameliorate symptoms for most patients.

Metabolic Rewiring in Response to Biguanides Is Mediated by mROS/HIF-1a in Malignant Lymphocytes.

Metabolic flexibility allows cells to adapt to various environments and limits the efficacy of metabolic drugs. Therapeutic targeting of cancer metabolism relies on defining limiting requirements and vulnerabilities in the highly dynamic metabolic network. Here, we characterize the metabolic reprogramming and identify cancer-specific metabolic vulnerabilities in response to the pharmacological inhibition of mitochondrial complex I. Our work reveals the adaptation mechanism in malignant lymphocytes providing resistance against the biguanides phenformin and metformin by transcriptionally reprogramming glucose metabolism. Metabolic adaptation to complex I inhibition is mediated by mitochondrial reactive oxygen species (mROS) serving as a mitochondrial stress signal activating hypoxia-inducible factor-1a (HIF-1a). Inhibition of the mROS/HIF-1a axis through antioxidants or direct suppression of HIF-1a selectively disrupts metabolic adaptation and survival during complex I dysfunction in malignant lymphocytes. Our results identify HIF-1a signaling as a critical factor in resistance against biguanide-induced mitochondrial dysfunction, allowing selective targeting of metabolic pathways in leukemia and lymphoma.

Proapoptotic protein BIM as a novel prognostic marker in mantle cell lymphoma.

Mantle cell lymphoma (MCL) is an aggressive B-cell lymphoma. Numerous studies have demonstrated many genetic aberrations in MCL in addition to the characteristic t(11:14), including frequent biallelic deletions of Bim, a proapoptotic member of the BCL-2 family. In mice, Bim deletion coupled with cyclin D1 overexpression generates pathologic and molecular features of human MCL. Since the regulation of apoptosis is crucial in MCL pathogenesis, we hypothesize that BIM expression may be associated with tumor cell survival. Clinical data and tissue from 100 nodal MCL cases between 1988 and 2009 were collected from three large academic medical centers. The average patient age of our MCL cohort was 65.5 years old (range, 42-97) with a 2:1 male to female ratio. Immunohistochemistry was performed with a validated anti-BIM antibody. Patients were separated into low and high BIM-expressing categories with a cutoff of 80%. As expected for a proapoptotic tumor suppressor, patients with high BIM expression were less likely to have progressive disease and more likely to have a complete response (P = .022). In addition, high BIM-expressing MCL tumors revealed a trend toward increased overall survival with this trend persisting in sub-analysis of Ann Arbor stages III and IV. No correlation between BIM expression, Ki-67 index, and MIPI score was observed, suggesting a role for BIM as a novel independent prognostic factor. While BIM is only one member of a complex family of apoptosis-regulating proteins, these findings may yield clinically relevant information for the prognosis and therapeutic susceptibility of MCL.

PRMT5 is upregulated by B-cell receptor signaling and forms a positive-feedback loop with PI3K/AKT in lymphoma cells.

PRMT5, which regulates gene expression by symmetric dimethylation of histones and non-histone target proteins, is overexpressed and plays a pathogenic role in many cancers. In diffuse large B cell lymphoma (DLBCL), the mechanisms of PRMT5 dysregulation and its role in lymphomagenesis remain largely unknown. Here we demonstrate that B cell receptor (BCR) signaling regulates PRMT5 expression in DLBCL cells. Immunohistochemical analysis reveals elevated levels of PRMT5 expression in DLBCL cases and in germinal center (GC) B cells when compared to naive B cells. PRMT5 can be induced in naive B cells by BCR stimulation. We discovered that BTK-NF-κB signaling induces PRMT5 transcription in activated B cell-like (ABC) DLBCL cells while BCR downstream PI3K-AKT-MYC signaling upregulates PRMT5 expression in both ABC and GCB DLBCL cells. PRMT5 inhibition inhibits the growth of DLBCL cells in vitro and patient derived xenografts. Genomic and biochemical analysis demonstrate that PRMT5 promotes cell cycle progression and activates PI3K-AKT signaling, suggesting a feedback regulatory mechanism to enhance cell survival and proliferation. Co-targeting PRMT5 and AKT by their specific inhibitors is lethal to DLBCL cell lines and primary cancer cells. Therefore, this study provides a mechanistic rationale for clinical trials to evaluate PRMT5 and AKT inhibitors for DLBCL.

Multicenter Analysis of Advanced Stage Grade 3A Follicular Lymphoma Outcomes by Frontline Treatment Regimen.

BACKGROUND: Follicular lymphoma (FL) is a common form of non-Hodgkin lymphoma with a wide spectrum of presentation. While grade 1/2 FL is considered low grade and grade 3B FL is approached as an aggressive lymphoma, the management of grade 3A FL remains controversial. PATIENTS AND METHODS: We performed a retrospective, multicenter analysis of patients aged ≥ 18 years with advanced stage 3/4 grade 3A FL diagnosed between January 2006 and July 2016. Patients were stratified by frontline chemotherapy regimen: anthracycline based (ATC), bendamustine (BD), and cyclophosphamide, vincristine, and prednisone (CVP). A total of 103 patients were identified from 6 contributing centers: 65 patients received ATC chemotherapy, 30 BD, and 8 CVP. The primary outcome was time to progression (TTP). Secondary outcomes included progression-free survival, overall survival, complete response rates, large cell transformation, and impact of standardized maximum uptake value on positron emission tomography/computed tomography with outcomes. Patient characteristics were similar among the 3 treatment groups. RESULTS: For TTP at 24 months from initiation of treatment, 72% of ATC, 79% of BD, and 50% of CVP patients had not experienced disease progression (P = .01). Multivariate analysis demonstrated a TTP benefit for ATC compared to CVP (hazard ratio 3.22; 95% confidence interval, 1.26-8.25; P = .01) but no difference when compared to BD. Similar findings were seen with progression-free survival. While overall survival was similar among the 3 arms, there was a higher risk of large cell transformation following BD and CVP. Last, standardized maximum uptake value on positron emission tomography/computed tomography did not affect TTP when comparing BD- and ATC-treated patients. CONCLUSION: Although ATC was superior to CVP, clinical outcomes (TTP, progression-free survival, and overall survival) were similar compared to BD chemotherapy for patients with grade 3A FL.

Chronic Myeloid Leukemia, Version 1.2019, NCCN Clinical Practice Guidelines in Oncology.

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome (Ph), resulting from a reciprocal translocation between chromosomes 9 and 22 [t(9;22] that gives rise to a BCR-ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase. Tyrosine kinase inhibitor (TKI) therapy is a highly effective first-line treatment option for all patients with newly diagnosed chronic phase CML (CP-CML). The selection TKI therapy should be based on the risk score, toxicity profile of TKI, patient's age, ability to tolerate therapy, and the presence of comorbid conditions. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with CP-CML.

VcR-CVAD Induction Chemotherapy Followed by Maintenance Rituximab Produces Durable Remissions in Mantle Cell Lymphoma: A Wisconsin Oncology Network Study.

INTRODUCTION: VcR-CVAD was developed as an intermediate-intensity induction regimen with maintenance rituximab (MR) to improve remission durations after first-line therapy for mantle cell lymphoma (MCL) in older and younger patients with MCL. PATIENTS AND METHODS: Patients with previously untreated MCL received VcR-CVAD induction chemotherapy for 6 cycles (21-day cycles). Patients achieving at least a partial response received rituximab consolidation (375 mg/m2 × 4 weekly doses) and MR (375 mg/m2 every 12 weeks × 20 doses). The primary endpoints were overall and complete response (CR), and the secondary endpoints were progression-free survival (PFS) and overall survival (OS). Thirty patients were enrolled, with a median age of 61 years. There was an even distribution of patients < 60 years and ≥ 60 years. Mantle cell lymphoma international prognostic index medium- or high-risk disease was present in 60%. The overall response rate observed was 90% (77% CR/unconfirmed CR). After a median follow-up of 7.8 years, the 6-year PFS and OS were 53% and 70%, respectively. There was no difference in 6-year PFS or OS between the younger (age < 60 years) and older (age ≥ 60 years) subgroups. In a univariate analysis, lactate dehydrogenase, when analyzed for interaction with age, had a significant effect on PFS outcomes at 6 years. There were no pretreatment variables determined to have a significant effect on OS outcomes at 6 years. CONCLUSIONS: Long-term outcomes with VcR-CVAD are comparable with more intensive inductions and consolidation approaches. MCL is biologically heterogeneous, and durable remission can be achieved with intermediate intensity therapy. MR appears to contribute to these excellent outcomes.

Pegivirus avoids immune recognition but does not attenuate acute-phase disease in a macaque model of HIV infection.

Human pegivirus (HPgV) protects HIV+ people from HIV-associated disease, but the mechanism of this protective effect remains poorly understood. We sequentially infected cynomolgus macaques with simian pegivirus (SPgV) and simian immunodeficiency virus (SIV) to model HIV+HPgV co-infection. SPgV had no effect on acute-phase SIV pathogenesis-as measured by SIV viral load, CD4+ T cell destruction, immune activation, or adaptive immune responses-suggesting that HPgV's protective effect is exerted primarily during the chronic phase of HIV infection. We also examined the immune response to SPgV in unprecedented detail, and found that this virus elicits virtually no activation of the immune system despite persistently high titers in the blood over long periods of time. Overall, this study expands our understanding of the pegiviruses-an understudied group of viruses with a high prevalence in the global human population-and suggests that the protective effect observed in HIV+HPgV co-infected people occurs primarily during the chronic phase of HIV infection.