Noninvasive positron emission tomography and fluorescence imaging of CD133+ tumor stem cells.

A technology that visualizes tumor stem cells with clinically relevant tracers could have a broad impact on cancer diagnosis and treatment. The AC133 epitope of CD133 currently is one of the best-characterized tumor stem cell markers for many intra- and extracranial tumor entities. Here we demonstrate the successful noninvasive detection of AC133(+) tumor stem cells by PET and near-infrared fluorescence molecular tomography in subcutaneous and orthotopic glioma xenografts using antibody-based tracers. Particularly, microPET with (64)Cu-NOTA-AC133 mAb yielded high-quality images with outstanding tumor-to-background contrast, clearly delineating subcutaneous tumor stem cell-derived xenografts from surrounding tissues. Intracerebral tumors as small as 2-3 mm also were clearly discernible, and the microPET images reflected the invasive growth pattern of orthotopic cancer stem cell-derived tumors with low density of AC133(+) cells. These data provide a basis for further preclinical and clinical use of the developed tracers for high-sensitivity and high-resolution monitoring of AC133(+) tumor stem cells.

Use of ChatGPT in Academic Publishing: A Rare Case of Seronegative Systemic Lupus Erythematosus in a Patient With HIV Infection.

Diagnosing systemic lupus erythematosus (SLE) may be difficult in cases of negative results for antinuclear antibodies (ANAs) and anti-double stranded DNA (dsDNA) antibodies, which is known as seronegative SLE. Additionally, in patients with HIV infection, the diagnosis of SLE is made complicated by the overlap of symptoms and the possibility of false negative results on antibody tests. Herein, we report the case of a 24-year-old female with HIV infection on anti-retroviral therapy who presented with vesicles and plaques over the malar area and ulcers over the roof of the mouth. Antibody tests for ANAs and dsDNA were negative. She was initially treated for herpes simplex with a secondary infection, but the symptoms did not improve. She ultimately died from acute myocardial infarction while awaiting results of direct immunofluorescence, which revealed the deposition of immunoglobulin (Ig) M, IgG, and C3 along the basement membrane, thus enabling a diagnosis of SLE. Therefore, SLE can be difficult to diagnose in patients with HIV, and other diagnostic criteria should be considered when suspecting SLE and treating these patients. Additionally, we also present our experience with ChatGPT (OpenAI LP, OpenAI Inc., San Francisco, CA, USA) in academic publishing and its pros and cons.

Genital and Extragenital Lichen Sclerosus et Atrophicus: A Case Series Written Using ChatGPT.

Background Lichen sclerosus et atrophicus (LSEA) is a chronic inflammatory dermatosis of genital and extragenital sites with a prevalence ranging from 9% in prepubertal patients to 50% in postmenopausal patients. Chat generative pre-trained transformer (ChatGPT) is an artificial intelligence tool designed to assist humans based on supervised and reinforcement techniques. In this study, we aimed to evaluate the characteristics of patients with LSEA using ChatGPT. Methods In this retrospective study, we included all patients who presented to the outpatient dermatology department during 2017-2022 at a tertiary care teaching hospital in South India. Information regarding demographic data, characteristics of LSEA, comorbidities, and associated autoimmune disorders was gathered using a medical chart review. Following data analysis and drafting of the manuscript, the utility of ChatGPT-3 and ChatGPT-4 in finalizing the draft was assessed. Results Of 20 patients diagnosed with LSEA, 16 (80%) and four (20%) patients were females and males, respectively. Of them, 50% of female patients had attained menopause. While 65% of patients had genital LSEA, 30% of patients had extragenital LSEA only, and 5% of patients had both genital and extragenital LSEA. Furthermore, four (20%) patients were prepubertal children. Of four male patients, two (50%) were younger than 18 years of age, and one patient was diagnosed with balanitis xerotica obliterans. The commonest associated features in LSEA included joint involvement (30%), hypertension (25%), and anemia (15%). Rare concomitant disorders included psoriasis, asthma, and basal cell carcinoma over the nose. Conclusions LSEA may be confused with other various dermatoses, such as morphea, vitiligo, and lichen planus. A high index of suspicion is required, especially in children, to diagnose it early and intervene to prevent further complications. Its relationship with autoimmune disorders and comorbidities warrants further large-scale studies. ChatGPT was unreliable in the literature search due to the provision of non-existent citations. ChatGPT-4 was better than ChatGPT-3 since it provided few true publications. ChatGPT was used in this study to summarize the articles identified by the authors during the literature search and to correct grammatical errors in the final draft of the manuscript.

A Sequential Targeting Strategy Interrupts AKT-Driven Subclone-Mediated Progression in Glioblastoma.

PURPOSE: Therapy resistance and fatal disease progression in glioblastoma are thought to result from the dynamics of intra-tumor heterogeneity. This study aimed at identifying and molecularly targeting tumor cells that can survive, adapt, and subclonally expand under primary therapy. EXPERIMENTAL DESIGN: To identify candidate markers and to experimentally access dynamics of subclonal progression in glioblastoma, we established a discovery cohort of paired vital cell samples obtained before and after primary therapy. We further used two independent validation cohorts of paired clinical tissues to test our findings. Follow-up preclinical treatment strategies were evaluated in patient-derived xenografts. RESULTS: We describe, in clinical samples, an archetype of rare ALDH1A1+ tumor cells that enrich and acquire AKT-mediated drug resistance in response to standard-of-care temozolomide (TMZ). Importantly, we observe that drug resistance of ALDH1A1+ cells is not intrinsic, but rather an adaptive mechanism emerging exclusively after TMZ treatment. In patient cells and xenograft models of disease, we recapitulate the enrichment of ALDH1A1+ cells under the influence of TMZ. We demonstrate that their subclonal progression is AKT-driven and can be interfered with by well-timed sequential rather than simultaneous antitumor combination strategy. CONCLUSIONS: Drug-resistant ALDH1A1+/pAKT+ subclones accumulate in patient tissues upon adaptation to TMZ therapy. These subclones may therefore represent a dynamic target in glioblastoma. Our study proposes the combination of TMZ and AKT inhibitors in a sequential treatment schedule as a rationale for future clinical investigation.

Overlapping Hyaline Fibromatosis Syndrome: A Rare Case of Juvenile Hyaline Fibromatosis and Infantile Systemic Hyalinosis.

Juvenile hyaline fibromatosis (JHF) and infantile systemic hyalinosis (ISF) are rare progressive, fatal autosomal recessive fibromatosis disorders that are characterized by the deposition of hyaline in various tissues. Mutations in capillary morphogenesis gene 2 are responsible for both of these conditions. These disorders usually present with fleshy, papular lesions, joint contractures, gingival hyperplasia, and persistent diarrhoea. An 18-month-old boy presented with multiple scalp abscesses, facial nodules, gingival hypertrophy, hypertrophic verrucous plaques and joint contractures with unique dermoscopic features and a history of recurrent diarrhoea and infections. Histopathological examination following skin biopsy revealed deposition of hyaline in the stroma and subcutaneous tissues. JHF is a differential diagnosis in children who present with multiple scalp nodules. Here, we report the case of overlapping features of JHF and ISH. The evolution of this case provides a special opportunity to further understand the pathogenesis and clinical characterization of hyaline fibromatosis syndrome.

Tumor-associated hematopoietic stem and progenitor cells positively linked to glioblastoma progression.

Brain tumors are typically immunosuppressive and refractory to immunotherapies for reasons that remain poorly understood. The unbiased profiling of immune cell types in the tumor microenvironment may reveal immunologic networks affecting therapy and course of disease. Here we identify and validate the presence of hematopoietic stem and progenitor cells (HSPCs) within glioblastoma tissues. Furthermore, we demonstrate a positive link of tumor-associated HSPCs with malignant and immunosuppressive phenotypes. Compared to the medullary hematopoietic compartment, tumor-associated HSPCs contain a higher fraction of immunophenotypically and transcriptomically immature, CD38- cells, such as hematopoietic stem cells and multipotent progenitors, express genes related to glioblastoma progression and display signatures of active cell cycle phases. When cultured ex vivo, tumor-associated HSPCs form myeloid colonies, suggesting potential in situ myelopoiesis. In experimental models, HSPCs promote tumor cell proliferation, expression of the immune checkpoint PD-L1 and secretion of tumor promoting cytokines such as IL-6, IL-8 and CCL2, indicating concomitant support of both malignancy and immunosuppression. In patients, the amount of tumor-associated HSPCs in tumor tissues is prognostic for patient survival and correlates with immunosuppressive phenotypes. These findings identify an important element in the complex landscape of glioblastoma that may serve as a target for brain tumor immunotherapies.

Restoration of T-cell Effector Function, Depletion of Tregs, and Direct Killing of Tumor Cells: The Multiple Mechanisms of Action of a-TIGIT Antagonist Antibodies.

TIGIT is an immune checkpoint inhibitor expressed by effector CD4+ and CD8+ T cells, NK cells, and regulatory T cells (Tregs). Inhibition of TIGIT-ligand binding using antagonistic anti-TIGIT mAbs has shown in vitro potential to restore T-cell function and therapeutic efficacy in murine tumor models when combined with an anti-PD(L)-1 antibody. In the current work, we demonstrate broader TIGIT expression than previously reported in healthy donors and patients with cancer with expression on γδ T cells, particularly in CMV-seropositive donors, and on tumor cells from hematologic malignancies. Quantification of TIGIT density revealed tumor-infiltrating Tregs as the population expressing the highest receptor density. Consequently, the therapeutic potential of anti-TIGIT mAbs might be wider than the previously described anti-PD(L)-1-like restoration of αß T-cell function. CD155 also mediated inhibition of γδ T cells, an immune population not previously described to be sensitive to TIGIT inhibition, which could be fully prevented via use of an antagonistic anti-TIGIT mAb (EOS-448). In PBMCs from patients with cancer, as well as in tumor-infiltrating lymphocytes from mice, the higher TIGIT expression in Tregs correlated with strong antibody-dependent killing and preferential depletion of this highly immunosuppressive population. Accordingly, the ADCC/ADCP-enabling format of the anti-TIGIT mAb had superior antitumor activity, which was dependent upon Fcγ receptor engagement. In addition, the anti-TIGIT mAb was able to induce direct killing of TIGIT-expressing tumor cells both in human patient material and in animal models, providing strong rationale for therapeutic intervention in hematologic malignancies. These findings reveal multiple therapeutic opportunities for anti-TIGIT mAbs in cancer therapeutics.

Checkpoint Antibodies but not T Cell-Recruiting Diabodies Effectively Synergize with TIL-Inducing γ-Irradiation.

T cell-recruiting bispecific antibodies (bsAb) show promise in hematologic malignancies and are also being evaluated in solid tumors. In this study, we investigated whether T cell-recruiting bsAbs synergize with hypofractionated tumor radiotherapy (hRT) and/or blockade of the programmed death-1 (PD-1) immune checkpoint, both of which can increase tumor-infiltrating lymphocyte (TIL) numbers. Unexpectedly, large melanomas treated with hRT plus bsAb (AC133×CD3) relapsed faster than those treated with hRT alone, accompanied by massive TIL apoptosis. This fast relapse was delayed by the further addition of anti-PD-1. Mechanistic investigations revealed restimulation-induced cell death mediated by BIM and FAS as an additional cause of bsAb-mediated TIL depletion. In contrast, the double combination of hRT and anti-PD-1 strongly increased TIL numbers, and even very large tumors were completely eradicated. Our study reveals the risk that CD3-engaging bsAbs can induce apoptotic TIL depletion followed by rapid tumor regrowth, reminiscent of tolerance induction by CD3 mAb-mediated T-cell depletion, warranting caution in their use for the treatment of solid tumors. Our findings also argue that combining radiotherapy and anti-PD-1 can be quite potent, including against very large tumors. Cancer Res; 76(16); 4673-83. ©2016 AACR.

Patient-derived glioblastoma stem cells are killed by CD133-specific CAR T cells but induce the T cell aging marker CD57.

The AC133 epitope of CD133 is a cancer stem cell (CSC) marker for many tumor entities, including the highly malignant glioblastoma multiforme (GBM). We have developed an AC133-specific chimeric antigen receptor (CAR) and show that AC133-CAR T cells kill AC133+ GBM stem cells (GBM-SCs) both in vitro and in an orthotopic tumor model in vivo. Direct contact with patient-derived GBM-SCs caused rapid upregulation of CD57 on the CAR T cells, a molecule known to mark terminally or near-terminally differentiated T cells. However, other changes associated with terminal T cell differentiation could not be readily detected. CD57 is also expressed on tumor cells of neural crest origin and has been preferentially found on highly aggressive, undifferentiated, multipotent CSC-like cells. We found that CD57 was upregulated on activated T cells only upon contact with CD57+ patient-derived GBM-SCs, but not with conventional CD57-negative glioma lines. However, CD57 was not downregulated on the GBM-SCs upon their differentiation, indicating that this molecule is not a bona fide CSC marker for GBM. Differentiated GBM cells still induced CD57 on CAR T cells and other activated T cells. Therefore, CD57 can apparently be upregulated on activated human T cells by mere contact with CD57+ target cells.

Effective Eradication of Glioblastoma Stem Cells by Local Application of an AC133/CD133-Specific T-cell-Engaging Antibody and CD8 T Cells.

Cancer stem cells (CSC) drive tumorigenesis and contribute to genotoxic therapy resistance, diffuse infiltrative invasion, and immunosuppression, which are key factors for the incurability of glioblastoma multiforme (GBM). The AC133 epitope of CD133 is an important CSC marker for GBM and other tumor entities. Here, we report the development and preclinical evaluation of a recombinant AC133×CD3 bispecific antibody (bsAb) that redirects human polyclonal T cells to AC133(+) GBM stem cells (GBM-SC), inducing their strong targeted lysis. This novel bsAb prevented the outgrowth of AC133-positive subcutaneous GBM xenografts. Moreover, upon intracerebral infusion along with the local application of human CD8(+) T cells, it exhibited potent activity in prophylactic and treatment models of orthotopic GBM-SC-derived invasive brain tumors. In contrast, normal hematopoietic stem cells, some of which are AC133-positive, were virtually unaffected at bsAb concentrations effective against GBM-SCs and retained their colony-forming abilities. In conclusion, our data demonstrate the high activity of this new bsAb against patient-derived AC133-positive GBM-SCs in models of local therapy of highly invasive GBM.