Identification of therapeutic targets applicable to clinical strategies in ovarian cancer

BACKGROUND: shRNA-mediated lethality screening is a useful tool to identify essential targets in cancer biology. Ovarian cancer (OC) is extremely heterogeneous and most cases are advanced stages at diagnosis. OC has a high response rate initially, but becomes resistant to standard chemotherapy. We previously employed high throughput global shRNA sensitization screens to identify NF-kB related pathways. Here, we re-analyzed our previous shRNA screens in an unbiased manner to identify clinically applicable molecular targets. METHODS: We proceeded with siRNA lethality screening using the top 55 genes in an expanded set of 6 OC cell lines. We investigated clinical relevance of candidate targets in The Cancer Genome Atlas OC dataset. To move these findings towards the clinic, we chose four pharmacological inhibitors to recapitulate the top siRNA effects: Oxozeaenol (for MAP3K7/TAK1), BI6727 (PLK1), MK1775 (WEE1), and Lapatinib (ERBB2). Cytotoxic effects were measured by cellular viability assay, as single agents and in 2-way combinations. Co-treatments were evaluated in either sequential or simultaneous exposure to drug for short term and extended periods to simulate different treatment strategies. RESULTS: Loss-of-function shRNA screens followed by short-term siRNA validation screens identified therapeutic targets in OC cells. Candidate genes were dysregulated in a subset of TCGA OCs although the alterations of these genes showed no statistical significance to overall survival. Pharmacological inhibitors such as Oxozeaenol, BI6727, and MK1775 showed cytotoxic effects in OC cells regardless of cisplatin responsiveness, while all OC cells tested were cytostatic to Lapatinib. Co-treatment with BI6727 and MK1775 at sub-lethal concentrations was equally potent to BI6727 alone at lethal concentrations without cellular re-growth after the drugs were washed off, suggesting the co-inhibition at reduced dosages may be more efficacious than maximal single-agent cytotoxic concentrations. CONCLUSIONS: Loss-of-function screen followed by in vitro target validation using chemical inhibitors identified clinically relevant targets. This approach has the potential to systematically refine therapeutic strategies in OC. These molecular target-driven strategies may provide additional therapeutic options for women whose tumors have become refractory to standard chemotherapy. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12885-016-2675-5) contains supplementary material, which is available to authorized users

HIV-Associated Lymphomas: Progress and New Challenges

The association of human immunodeficiency virus (HIV) and aggressive lymphomas was first reported in 1982. Before the development of effective HIV antiviral therapy, the incidence and the mortality of these lymphomas was high, with patients frequently succumbing to the disease. More lately, the combination of cART with chemoimmunotherapy significantly improved the survival outcome of the HIV-lymphomas. In this review, we discuss on describing the incidence of HIV-associated lymphomas, their clinical features, and the latest advances in the management of the various lymphoma subtypes

PI3K signaling pathway in normal B cells and indolent B-cell malignancies

In chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphomas (NHLs), B-cell receptor signaling leads to activation of the phosphatidylinositol 3-kinase (PI3K) pathway. Idelalisib, a PI3Kδ inhibitor was approved in 2014 by the US Food and Drug Administration (FDA) in combination with rituximab for the treatment of patients with CLL for whom single-agent rituximab would be considered appropriate and as a single agent for patients with relapsed small lymphocytic lymphoma (SLL) and relapsed follicular lymphoma (FL). Following its approval, several trials investigating various PI3Kδ inhibitors as single agents or in combination with chemoimmunotherapy or other molecular targeted agents in CLL and indolent NHL (iNHL) have uncovered some severe autoimmune related toxicities. This review discusses and summarizes the biologic basis and the clinical experience of the PI3Kδ inhibitors in indolent B-cell malignancies

HIV-Associated Lymphomas: Progress and New Challenges

The association of human immunodeficiency virus (HIV) and aggressive lymphomas was first reported in 1982. Before the development of effective HIV antiviral therapy, the incidence and the mortality of these lymphomas was high, with patients frequently succumbing to the disease. More lately, the combination of cART with chemoimmunotherapy significantly improved the survival outcome of the HIV-lymphomas. In this review, we discuss on describing the incidence of HIV-associated lymphomas, their clinical features, and the latest advances in the management of the various lymphoma subtypes

Innovations in Antibody-Drug Conjugate (ADC) in the Treatment of Lymphoma

Chemoimmunotherapy and cellular therapy are the mainstay of the treatment of relapsed/refractory (R/R) lymphomas. Development of resistance and commonly encountered toxicities of these treatments limit their role in achieving desired response rates and durable remissions. The Antibody–Drug Conjugate (ADC) is a novel class of targeted therapy that has demonstrated significant efficacy in treating various cancers, including lymphomas. To date, three ADC agents have been approved for different lymphomas, marking a significant advancement in the field. In this article, we aim to review the concept of ADCs and their application in lymphoma treatment, provide an analysis of currently approved agents, and discuss the ongoing advancements of ADC development

Antiplatelet factor 4/heparin antibodies in patients with gram negative bacteremia

Heparin-induced thrombocytopenia (HIT) is an antibody-mediated syndrome of thrombocytopenia and prothrombotic state that follows exposure to heparin. However, spontaneous HIT has been described in the setting of infection, without evidence of previous heparin administration. Since PF4 binds to lipid A portion of lipopolysaccharide, we tested for the presence of antiPF4/heparin antibodies in patients with gram-negative bacteremia. Patients with bacteremia had higher titers of antiPF4/heparin antibodies compared to normal controls 26.3 +/- SD 34 units, N = 32 versus 6.3 +/- SD 2.38 units, N = 10, P = 0.001. FITC-labeled PF4 interacted with lipopolysaccharide in a concentration-dependent manner as determined by quenching of the emission spectrum following excitation at lambda 488. In addition, immunoaffinity purified antiPF4/Heparin antibodies from 3 patients with HIT cross-reacted with PF4/heparin complex. These results show that PF4/LPS complex is immunogenic and can elicit cross-reacting antibodies against PF4/Heparin, providing an explanation for the presence of these antibodies in individuals, who were never been exposed to heparin before. These antibodies may also be at least partly responsible for the thrombocytopenia associated with infection. Published by Elsevier Ltd

Outcomes in peripheral T-cell lymphomas: An analysis of patients treated at a single academic institution

e19524 Background: T-cell lymphomas are a heterogeneous group of lymphomas, including the cutaneous T cell lymphoma (CTCL) and the peripheral T cell lymphomas (PTCL). Regarding the PTCL, it’s a heterogeneous group including approximately 23 different diseases with the peripheral T-cell lymphoma not otherwise specified (PTCL NOS), angioimmunoblastic lymphoma (AITL), and anaplastic large cell lymphoma (ALCL) being the most frequent subtypes. In contrast with the B cell lymphomas, most of the PTCL have a worse prognosis. We aim in our study to quantify the prognosis in each of the most frequent subtypes of PTCL. Methods: We analyzed patients with either PTCL NOS, AITL, or ALCL treated at Sylvester Comprehensive Cancer Center between 2010 and 2020. We calculated overall survival (OS) using the Kaplan-Meier method with Log-Rank Test to estimate the 95% confidence interval. Results: 98 patients belonged to 1 of the 3 major T-cell lymphoma subtypes: 43 to PTCL NOS, 33 to AITL, and 20 to ALCL, being 7 ALK-positive and 13 ALK-negative. Mean age in PTCL NOS, AITL and ALCL was 56 years (ranging from 8-88), 62 (8-89), and 52 (1-79), respectively. In PTCL NOS, AITL and ALCL respectively, 21 (46%), 15 (45%) and 7 (35%) of patients were female. The three-year and five-year overall survival was 62% (95% CI 42-82) and 30% (95% CI 6-54%) in PTCL NOS, 64% (95% CI 44-84) and 42% (95% CI 4-78%) in AITL, 75 (95% CI 51-99) and 67% (95% CI 33-100) in ALK-negative ALCL. There were no reported deaths in ALK-positive ALCL. The mean survival was lowest in PTCL NOS (p = 0.02), being 3,6 years, while AITL it is 5.2 and in ALCL it is 8.4. Conclusions: Amongst the three major subtypes of PTCL, PTCL NOS have the worse prognosis. Future research is needed to develop a risk stratification tool in each subtype

Outcomes of Richter’s syndrome in patients with chronic lymphocytic leukemia (CLL) treated with platinum or anthracycline based chemotherapy with or without a BTK inhibitor (BTKi)

e19511 Background: Richter’s syndrome (RS) is a rare complication of chronic lymphocytic leukemia (CLL) and the median survival is generally poor. Evidence is limited regarding the biology of the disease, treatment and outcomes. Methods: We retrospectively reviewed pts diagnosed (dx) with pathologically confirmed RS who presented at the University of Miami Sylvester Cancer Center between 2011 and 2020. Informed consent was provided through IRB-approved protocols. Descriptive statistics were utilized and overall survival (OS) was calculated from RS diagnosis to death or last follow-up by Kaplan-Meier. Results: 33 patients with RS, including 87.9% diffuse large B-cell lymphoma-type RS and 12.1% Hodgkin lymphoma-type RS were identified. Median time from CLL dx to RS transformation was 37months (m). Most patients presented with elevated LDH 75%, bulky lymphadenopathy 66%, and adverse genetic features, such as TP53 disruption 52% or complex karyotype 81%. FISH at RS dx: del(17p) 37%, del(11q) 17%, trisomy 12 58%. ORR to first line therapy was 75.8% (55% CR, 27% PR), but of those who achieved CR, 44% relapsed. Median PFS (mPFS) was 10m for the anthracycline-based chemotherapy group (ABC) with a CR of 50%, compared to 15.5 m for the platinum-based chemotherapy group (PBC) and a CR of 60%. Similar OS were observed regardless of the chemotherapy regimen with median OS (mOS) of 60 m in the ABC group vs 59.5 m in the PBC group. Notably, the addition of a BTKi to chemoimmunotherapy lead to a mOS of more than 10 years in BTKi-naïve pts compared to 5.1 years in BTKi-exposed pts and 1.8 years in pts who did not receive a BTKi for RS treatment. Conclusions: Patients who develop RS often have high risk CLL, especially complex cytogenetics. Although a large proportion of pts with RS respond to frontline therapy, almost half relapse. While mOS is similar for anthracycline and platinum-based chemotherapies, platinum-based chemotherapy can lead to superior CR and PFS. BTKi-naïve pts who receive a BTKi with chemotherapy for RS treatment have superior mOS