Transcriptional reprogramming by mutated IRF4 in lymphoma

Disease-causing mutations in genes encoding transcription factors (TFs) can affect TF interactions with their cognate DNA-binding motifs. Whether and how TF mutations impact upon the binding to TF composite elements (CE) and the interaction with other TFs is unclear. Here, we report a distinct mechanism of TF alteration in human lymphomas with perturbed B cell identity, in particular classic Hodgkin lymphoma. It is caused by a recurrent somatic missense mutation c.295 T > C (p.Cys99Arg; p.C99R) targeting the center of the DNA-binding domain of Interferon Regulatory Factor 4 (IRF4), a key TF in immune cells. IRF4-C99R fundamentally alters IRF4 DNA-binding, with loss-of-binding to canonical IRF motifs and neomorphic gain-of-binding to canonical and non-canonical IRF CEs. IRF4-C99R thoroughly modifies IRF4 function by blocking IRF4-dependent plasma cell induction, and up-regulates disease-specific genes in a non-canonical Activator Protein-1 (AP-1)-IRF-CE (AICE)-dependent manner. Our data explain how a single mutation causes a complex switch of TF specificity and gene regulation and open the perspective to specifically block the neomorphic DNA-binding activities of a mutant TF.

Short-term risk prediction after major lower limb amputation: PERCEIVE study

BACKGROUND

The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery.

METHODS

The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance.

RESULTS

Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679).

CONCLUSION

Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.

Aberrant Expression of and Cell Death Induction by Engagement of the MHC-II Chaperone CD74 in Anaplastic Large Cell Lymphoma (ALCL)

Simple Summary

Anaplastic large cell lymphoma (ALCL) is a lymphoid malignancy considered to be derived from T cells. Currently, two types of systemic ALCL are distinguished: anaplastic lymphoma kinase (ALK)-positive and ALK-negative ALCL. Although ALK⁺ and ALK⁻ ALCL differ at the genomic and molecular levels, various key biological and molecular features are highly similar between both entities. We have developed the concept that both ALCL entities share a common principle of pathogenesis. In support of this concept, we here describe a common deregulation of CD74, which is usually not expressed in T cells, in ALCL. Ligation of CD74 induces cell death of ALCL cells in various conditions, and an anti-CD74-directed antibody-drug conjugate efficiently kills ALCL cell lines. Furthermore, we reveal expression of the proto-oncogene and known CD74 interaction partner MET in a fraction of ALCL cases. These data give insights into ALCL pathogenesis and might help to develop new treatment strategies for ALCL.

Abstract

In 50–60% of cases, systemic anaplastic large cell lymphoma (ALCL) is characterized by the t(2;5)(p23;q35) or one of its variants, considered to be causative for anaplastic lymphoma kinase (ALK)-positive (ALK⁺) ALCL. Key pathogenic events in ALK-negative (ALK⁻) ALCL are less well defined. We have previously shown that deregulation of oncogenic genes surrounding the chromosomal breakpoints on 2p and 5q is a unifying feature of both ALK⁺ and ALK⁻ ALCL and predisposes for occurrence of t(2;5). Here, we report that the invariant chain of the MHC-II complex CD74 or li, which is encoded on 5q32, can act as signaling molecule, and whose expression in lymphoid cells is usually restricted to B cells, is aberrantly expressed in T cell-derived ALCL. Accordingly, ALCL shows an altered DNA methylation pattern of the CD74 locus compared to benign T cells. Functionally, CD74 ligation induces cell death of ALCL cells. Furthermore, CD74 engagement enhances the cytotoxic effects of conventional chemotherapeutics in ALCL cell lines, as well as the action of the ALK-inhibitor crizotinib in ALK⁺ ALCL or of CD95 death-receptor signaling in ALK⁻ ALCL. Additionally, a subset of ALCL cases expresses the proto-oncogene MET, which can form signaling complexes together with CD74. Finally, we demonstrate that the CD74-targeting antibody-drug conjugate STRO-001 efficiently and specifically kills CD74-positive ALCL cell lines in vitro. Taken together, these findings enabled us to demonstrate aberrant CD74-expression in ALCL cells, which might serve as tool for the development of new treatment strategies for this lymphoma entity.

Super-enhancer-based identification of a BATF3/IL-2R-module reveals vulnerabilities in anaplastic large cell lymphoma

Anaplastic large cell lymphoma (ALCL), an aggressive CD30-positive T-cell lymphoma, comprises systemic anaplastic lymphoma kinase (ALK)-positive, and ALK-negative, primary cutaneous and breast implant-associated ALCL. Prognosis of some ALCL subgroups is still unsatisfactory, and already in second line effective treatment options are lacking. To identify genes defining ALCL cell state and dependencies, we here characterize super-enhancer regions by genome-wide H3K27ac ChIP-seq. In addition to known ALCL key regulators, the AP-1-member BATF3 and IL-2 receptor (IL2R)-components are among the top hits. Specific and high-level IL2R expression in ALCL correlates with BATF3 expression. Confirming a regulatory link, IL-2R-expression decreases following BATF3 knockout, and BATF3 is recruited to IL2R regulatory regions. Functionally, IL-2, IL-15 and Neo-2/15, a hyper-stable IL-2/IL-15 mimic, accelerate ALCL growth and activate STAT1, STAT5 and ERK1/2. In line, strong IL-2Rα-expression in ALCL patients is linked to more aggressive clinical presentation. Finally, an IL-2Rα-targeting antibody-drug conjugate efficiently kills ALCL cells in vitro and in vivo. Our results highlight the importance of the BATF3/IL-2R-module for ALCL biology and identify IL-2Rα-targeting as a promising treatment strategy for ALCL.

Anaplastic large cell lymphoma (ALCL) is an aggressive T-cell lymphoma often with poor prognosis. To identify genes defining ALCL cell state and dependencies, the authors here characterize ALCL-specific super-enhancers and describe the BATF3/IL-2R−module as a therapeutic opportunity for ALCL.

The AP-1-BATF and -BATF3 module is essential for growth, survival and TH17/ILC3 skewing of anaplastic large cell lymphoma

Transcription factor AP-1 is constitutively activated and IRF4 drives growth and survival in ALK⁺ and ALK^- anaplastic large cell lymphoma (ALCL). Here we demonstrate high-level BATF and BATF3 expression in ALCL. Both BATFs bind classical AP-1 motifs and interact with in ALCL deregulated AP-1 factors. Together with IRF4, they co-occupy AP-1-IRF composite elements, differentiating ALCL from non-ALCL. Gene-specific inactivation of BATFs, or global AP-1 inhibition results in ALCL growth retardation and/or cell death in vitro and in vivo. Furthermore, the AP-1-BATF module establishes TH17/group 3 innate lymphoid cells (ILC3)-associated gene expression in ALCL cells, including marker genes such as AHR, IL17F, IL22, IL26, IL23R and RORγt. Elevated IL-17A and IL-17F levels were detected in a subset of children and adolescents with ALK⁺ ALCL. Furthermore, a comprehensive analysis of primary lymphoma data confirms TH17-, and in particular ILC3-skewing in ALCL compared with PTCL. Finally, pharmacological inhibition of RORC as single treatment leads to cell death in ALCL cell lines and, in combination with the ALK inhibitor crizotinib, enforces death induction in ALK⁺ ALCL. Our data highlight the crucial role of AP-1/BATFs in ALCL and lead to the concept that some ALCL might originate from ILC3.

An Intervention for Moving Long Overdue Women To Get a Mammogram

Background: While there is substantial evidence that mammography screening decreases breast cancer mortality, as many 15 million American women are overdue for a biennial mammogram. This pilot study addressed the usefulness of a computer-assisted telephone counseling program in motivating reluctant or resistant women to get a mammogram.Methods: 127 women, aged 45-79, enrolled in primary care practices and without a documented mammogram for >=27 months were identified, approved by providers and eligible for study. All women had adequate health insurance and all had received a screening recommendation from their provider. The intervention included a mailed educational booklet followed by tailored counseling call, motivational interviewing and facilitated short-interval test scheduling. Using a computer-assisted telephone counseling program, the counselor identified the subject's stage of readiness to get a mammogram, reviewed the booklet in detail, clarified any misinformation and discussed specific barriers. At the conclusion of counseling, the counselor used motivational interviewing techniques to reconcile subjects' stated values with their stage of readiness. Outcome measures included stage change and completed mammograms within 12 months of the call as documented in the claims data.Results: Of the 127 eligible women, 45 (35%) agreed to counseling. 11% of these women had never had a mammogram, 7% had not had one in 48-59 months; 62% had not had one in>=60 months. At the start of the call, 11% had decided not to get mammograms, 16% were undecided about whether to get one, 44% were planning to get one but had no specific appointment and 4% had a mammogram appointment. Of these 45 women, 73% moved 1 or more stages closer to getting a mammogram. Of 13 women initially not planning to get a mammogram, 3 scheduled a mammogram and 3 stated an intention to get one. 75 % of women who scheduled a mammogram with the counselor went on to complete the test. 58% of the 45 counseled women actually got a mammogram. Of the 82 eligible women who refused to be in the study or did not respond to the telephone calls, only 21% got a mammogram. (57.8% vs. 21.3%, p<.001)Conclusions: It is possible to reach mammogram-reluctant women and to move them to complete a mammogram. Many of the counseled women were not against having mammograms but had no definite plans to get one. Women who schedule a mammogram are likely to keep the appointment. Given the low rate of mammography in those refusing to participate or not answering our calls, we suspect this group held a large number of mammogram-resistant women.For these women, additional interventions, such a monetary enhancement might prove useful. A prospective controlled trial to evaluate this intervention is currently underway. Supportedby NIH R21-100286

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6076.

Outcome of the current management of splenic injuries

BACKGROUND

For patients > 55 years, nonoperative management (NOM) of blunt splenic injury remains controversial. Conflicting reports of excessively high or acceptably low failure rates have discouraged widespread application of NOM in these older patients. However, the small number of patients in these studies limits the impact of their conclusions.

METHODS

We manage splenic injury nonoperatively in all appropriate patients without regard to age. We present the largest series of patients > 55 years who have been managed nonsurgically, in a retrospective review of all patients with blunt splenic injury admitted to our trauma center between 1996 and 1999.

RESULTS

In 4 years, 542 patients were admitted with blunt splenic injury. Eighty-three patients were > 55 years, and 61 of these patients underwent NOM. Seven older patients failed NOM and required delayed splenectomy, yielding a failure rate of 11.4%. This failure rate was statistically equivalent to the 7% failure rate of patients < 55 years. This study has a power of 80% to detect a failure rate change from 7% to 20%. By multivariate analysis, the only factor that significantly increased the risk of NOM failure was splenic injury grade. Patients > 55 years had a higher mortality than younger patients regardless of NOM/operative treatment. Splenic injury did not directly cause any of the deaths in patients > 55 years who had NOM or failure of NOM. High-grade splenic injuries fail NOM in those > 55 years.

CONCLUSION

Nonoperative management of lower grade splenic injuries in patients > 55 years can be accomplished with an acceptably low failure rate. Only grade of splenic injury, not patient age, increases the risk of NOM failure.

Underusers of mammogram screening: stage of adoption in five U.S. subpopulations. The NCI Breast Cancer Screening Consortium

BACKGROUND

The purpose of this report is to describe the characteristics of women ages 50 to 80 who do not follow commonly accepted mammography screening guidelines. It provides unique understanding of the robustness of characteristics of underusers across five different U.S. subpopulations.

METHODS

The data are from the baseline surveys of the five studies of the NCI Breast Cancer Screening Consortium. Stage of adoption of mammography screening and other characteristics of underusers are presented. Polytomous logistic regression analysis was used to explore multivariable associations with stage of adoption in each study site.

RESULTS

The five samples studied by the Consortium range in size from 259 to 4,477 women (n = 11,292). The relationship of the perceptions of the pros and cons of mammography with stage of adoption was strikingly similar across the five samples. Other variables consistently associated with stage were a recent receipt of a breast physical examination and recommendation for mammography by a physician.

CONCLUSIONS

The findings suggest a need to encourage regular screening through effective communication from a health care provider. Intervention messages should be designed to increase the pros of mammography, decrease the cons, and highlight these differentially according to the woman's stage of adoption.

American Cancer Society guidelines for the early detection of breast cancer: update 1997

The American Cancer Society (ACS) convened a workshop in March 1997 to consider new scientific findings related to breast cancer screening and to determine whether these findings warrant a change in the existing ACS guidelines. The meeting was timed so that participants could benefit from new data related to screening women aged 40 to 49 years. A recommendation based on the new data and subsequently approved by the ACS Board of Directors is reported.

Importance of albumin, 25(OH)-vitamin D and IGFBP-3 as risk factors in elderly women and men with hip fracture

The relative importance of vitamin D deficiency, secondary hyperparathyroidism, nutritional deficiency and low bone mineral density (BMD) as risk factors for hip fracture is not definitely established. In the framework of a case-control study of risk factors for hip fractures, biochemical markers of bone metabolism and nutrition and femoral BMD data were compared in 136 female and 43 male hip fracture patients, 136 female and 44 male age-matched hospitalized controls, and 47 healthy elderly women (8 men). Patients with hip fracture had lower albumin (-10%) and 25(OH)-vitamin D (25(OH)D; -19%) compared with hospitalized controls, and lower albumin (-28%) and 25(OH)D levels (-52%) compared with the elderly controls. Serum values of IGFBP-3 were also significantly lower (-33%) in hip fracture patients than in community controls. BMD of femoral neck was lower (p < 0.001) in patients than in hospitalized and community controls. In hip fracture patients, parathyroid hormone (PTH) correlated weakly with BMD (neck: r = -0.19, trochanter: r = -0.17; both p < 0.05). When all women were pooled (n = 233), albumin correlated significantly (age-adjusted) with BMD at all sites (neck: r = 0.27, trochanter: r = 0.25; all p < 0.001). Albumin, but not 25(OH)D, also correlated with skinfold thickness (r = 0.19, p < 0.0025) and with body mass index (BMI) (r = 0.14, p < 0.05). Male patients with hip fracture had lower BMD and albumin (both p < 0.001), 25(OH)D (p = 0.02) and IGFBP-3 levels (p < 0.005) compared with the controls. When male patients and controls were pooled together, albumin, skinfold thickness and BMI were significantly correlated with each other, but not with BMD. IGFBP-3 was highly correlated with albumin (p < 0.0001), 25(OH)D (p < 0.005) and, less significantly, with PTH (p < 0.05), but not with BMI or skinfold thickness. IGFBP-3 was significantly correlated with BMD at all sites (neck: r = 0.27, p < 0.05; trochanter: r = 0.40, p < 0.0005). In conclusion, low albumin and low BMD were both important risk factors for hip fracture. Low serum albumin was the strongest independent variable correlated with hip fractures. In men. IGFBP-3 was correlated with BMD. The femoral BMD depended only weakly on PTH and 25(OH)D, but was correlated at all sites with albumin, a non-specific parameter of nutrition and general health.

Population pharmacodynamic study of amonafide: a Cancer and Leukemia Group B study

PURPOSE

To determine if variability in toxicity of amonafide during phase II trials could be correlated with pharmacokinetic variability.

PATIENTS AND METHODS

Seventy-three patients enrolled onto three Cancer and Leukemia Group B (CALGB) phase II trials of amonafide (300 mg/m2 daily for 5 days) were studied, using a limited sampling strategy (45 minutes and 24 hours) to estimate the amonafide area under the plasma concentration-time curve (AUC). Concentrations of N-acetyl-amonafide, an active metabolite, were also determined.

RESULTS

The primary determinant of toxicity at a fixed dose of amonafide was the extent of N-acetylation. Fast acetylators (36% of patients) had significantly greater toxicity than slow acetylators (64% of patients), with median WBC nadirs of 500/microL and 3,400/microL, respectively (P < or = .001). In a multivariate analysis, lower pretreatment WBC count, lower albumin level, and nonwhite race were also independently associated with toxicity. Further analysis of interracial differences demonstrated that minority women had slower clearance of amonafide (P = .026) and a higher incidence of grade 4 leukopenia (P = .042).

CONCLUSION

The highly variable toxicity of amonafide is primarily due to genetic differences in N-acetylation. Other genetic (race) and acquired factors (baseline WBC count and albumin level) also appear to influence the extent of toxicity observed following administration of this agent.

A feasibility study of intensive CAF as outpatient adjuvant therapy for stage II breast cancer in a cooperative group: CALGB 8443

In preparation for a national Phase III study of dose and dose intensity in the treatment of node-positive, Stage II adenocarcinoma of the female breast, CALGB instituted a pilot study of intensive intravenous outpatient CAF (cyclophosphamide, Adriamycin, 5-fluorouracil) for four months. This study was designed to give full doses of drugs without dose reduction for hematologic toxicity. In order to evaluate the feasibility of physician and patient compliance with a potentially toxic therapy, a multi-institution pilot study was performed. This protocol demonstrated that a cooperative group could deliver toxic drug doses to outpatients with a median of 98% of cyclophosphamide, 97% of Adriamycin (doxorubicin), and 91% of 5-fluorouracil administered on schedule. Major side effects, as expected, were leukopenia, nausea, and vomiting. Disease-free survival is at least equivalent to that observed in previous studies.

Binding of optically pure (--)-[3H]nicotine to rat brain membranes

With the recent availability of (--)-[3H]nicotine of high specific activity, binding studies were performed on rat brain membranes in the presence of a variety of nicotine analogues and cholinergic drugs. Both a higher affinity (Kd = 2 X 10(-10) M) and a lower affinity (2 X 10(-9) M) site were observed; the stereoselectivity of both sites being similar. A good correlation was observed between IC50-values and psychotropic potency of a series of N'-alkyl substituted nicotine analogues.