In chronic myeloid leukemia, the identification of early molecular predictors of stable treatment-free remission (TFR) after tyrosine kinase inhibitor (TKI) discontinuation is challenging. The ...predictive values of residual disease (BCR::ABL1 quantification) at months 3 and 6 and more recently, BCR::ABL1 transcript halving time (HT) have been described, but no study compared the predictive value of different early parameters. Using a real-world cohort of 408 patients, we compared the performance of the ELTS score, BCR::ABL1 HT, and residual disease at month 3 and 6 to predict the molecular response, achievement of the TKI discontinuation criteria, and TFR maintenance. The performances of BCR::ABL1 HT and residual disease at month 3 were similar. Residual disease at month 6 displayed the best performance for predicting the optimal response (area under the ROC curve between 0.81 and 0.92; cut-off values: 0.11% for MR4 at month 24 and 0.12% for MR4.5 at month 48). Conversely, no early parameter predicted reaching the TKI discontinuation criteria and TFR maintenance. We obtained similar results when patients were divided in subgroups by first-line treatment (imatinib vs second generation TKI, 2G-TKI). We identified a relationship between ELTS score, earlier milestones and TFR maintenance only in the 2G-TKI group. In conclusion, this first comparative study of early therapeutic response parameters showed that they are excellent indicators of TKI efficacy (BCR::ABL1 transcript reduction) and best responders. Conversely, they did not predict the achievement of the TKI discontinuation criteria and TFR maintenance, suggesting that other parameters are involved in TFR maintenance.
Clinical-grade human mesenchymal stromal cells (MSCs) have been expanded in vitro for tissue engineering or immunoregulatory purposes without standardized culture conditions or release criteria. ...Although human MSCs show poor susceptibility for oncogenic transformation, 2 recent studies described their capacity to accumulate chromosomal instability and to give rise to carcinoma in immunocompromised mice after long-term culture. We thus investigated the immunologic and genetic features of MSCs expanded with fetal calf serum and fibroblast growth factor or with platelet lysate in 4 cell-therapy facilities during 2 multicenter clinical trials. Cultured MSCs showed a moderate expression of human leukocyte antigen-DR without alteration of their low immunogenicity or their immunomodulatory capacity. Moreover, some transient and donor-dependent recurring aneuploidy was detected in vitro, independently of the culture process. However, MSCs with or without chromosomal alterations showed progressive growth arrest and entered senescence without evidence of transformation either in vitro or in vivo.
Guidelines for tyrosine kinase inhibitor (TKI)-treated chronic phase-chronic myeloid leukemia (CML) management are essentially based on data from clinical research trials; however, real-world data ...should be valuable for optimizing such recommendations. Here, we analyzed the data collected in the French CML Observatory database, a multicenter real-world cohort (
n
= 646), using a first-line “intention-to-treat” analysis strategy. This cohort included patients treated with first-line imatinib (
n
= 484), nilotinib (
n
= 103), dasatinib (
n
= 17), imatinib and interferon (
n
= 9), or second-generation (2G)-TKIs and interferon (
n
= 29). The cumulative incidence of major molecular response (MMR), MR4, MR4.5 and MR5 confirmed the faster response kinetics with 2G-TKIs. Multivariate analysis identified being a woman and residual disease at month 6 as the main predictive factors of deep molecular response (DMR). Moreover, 30% of patients met the criteria for treatment discontinuation (5 years of treatment and ≥ 2 years of DMR), but only 38% of them stopped treatment. Among the 92 patients who actually discontinued treatment due to optimal response, 31.5% relapsed (48% of them after > 6 months of TKI discontinuation). Multivariate analysis identified age and TKI duration as factors positively correlated with treatment-free remission maintenance. Late (> 6 months) relapses were more frequent in patients with the e14a2 BCR::ABL transcript. Relapse rate was higher in patients who stopped TKI before than after 5 years of treatment (52.6% vs 26%;
p
= 0.040). These results advocate caution concerning early treatment withdrawal, including in patients receiving 2G-TKIs. This still recruiting database is a valuable source of information for the real-world follow-up of patients with CML.
Telomeres are nucleoprotein structures at the end of chromosomes which stabilize and protect them from nucleotidic degradation and end-to-end fusions. The G-rich telomeric single-stranded DNA ...overhang can adopt a four-stranded G-quadruplex DNA structure (G4). Stabilization of the G4 structure by binding of small molecule ligands enhances radiosensitivity of tumor cells, and this combined treatment represents a novel anticancer approach. We studied the effect of the platinum-derived G4-ligand, Pt-ctpy, in association with radiation on human glioblastoma (SF763 and SF767) and non-small cell lung cancer (A549 and H1299) cells in vitro and in vivo. Treatments with submicromolar concentrations of Pt-ctpy inhibited tumor proliferation in vitro with cell cycle alterations and induction of apoptosis. Non-toxic concentrations of the ligand were then combined with ionizing radiation. Pt-ctpy radiosensitized all cell lines with dose-enhancement factors between 1.32 and 1.77. The combined treatment led to increased DNA breaks. Furthermore, a significant radiosensitizing effect of Pt-ctpy in mice xenografted with glioblastoma SF763 cells was shown by delayed tumor growth and improved survival. Pt-ctpy can act in synergy with radiation for efficient killing of cancer cells at concentrations at which it has no obvious toxicity per se, opening perspectives for future therapeutic applications.
Radiation therapy plays a central role in the treatment of glioblastoma, but it is not curative due to the high tumor radioresistance. Phosphatidyl-inositol 3-kinase/protein kinase B (Akt) and Janus ...kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathways serve to block the apoptosis process, keeping cells alive in very toxic environments such as chemotherapy or ionizing radiation. In the present study, from a panel of 8 human malignant glioma cell lines, investigations on the relationship between intrinsic radioresistance and Akt or STAT3 basal activation were done. Secondly, the impact of down-modulation of Akt or STAT3 signaling on in vitro intrinsic radiosensitivity was evaluated. Using a clonogenic cell survival assay, our results revealed a significant correlation between the basal Akt activation and the surviving fraction at 2 Gy (SF2). In contrast, no correlation was found between STAT3 activation and SF2. According to this, down-modulation of Akt with a specific chemical inhibitor (Akt inhibitor IV) demonstrated a significant enhancement of radiation sensitivity on glioma cells in a clonogenic survival assay. On the contrary, down-modulation of STAT3 signaling with a specific chemical inhibitor (JSI-124) or a neutralizing gp130 antibody failed to radiosensitize glioma cells. These data indicate that the Akt intercept node could be a more relevant therapeutic target than STAT3 for radiosensitizing human malignant glioma.
Ewing sarcoma (EWS) is a common pediatric solid tumor with high metastatic potential. Due to toxic effects of treatments on reproductive functions, the cryopreservation of ovarian tissue (OT) or ...testicular tissue (TT) is recommended to preserve fertility. However, the risk of reintroducing residual metastatic tumor cells should be evaluated before fertility restoration. Our goal was to validate a sensitive and specific approach for EWS minimal residual disease (MRD) detection in frozen germinal tissues. Thawed OT (
= 12) and TT (
= 14) were contaminated with tumor RD-ES cells (10, 100, and 1000 cells) and EWS-FLI1 tumor-specific transcript was quantified with RT-qPCR. All contaminated samples were found to be positive, with a strong correlation between RD-ES cell numbers and EWS-FLI1 levels in OT (
= 0.93) and TT (
= 0.96) (
< 0.001). No transcript was detected in uncontaminated control samples. The invasive potential of Ewing cells was evaluated using co-culture techniques. After co-culturing, tumor cells were detected in OT/TT with histology, FISH, and RT-qPCR. In addition, four OT and four TT samples from children with metastatic EWS were tested, and no MRD was found using RT-qPCR and histology. We demonstrated the high sensitivity and specificity of RT-qPCR to detect EWS MRD in OT/TT samples. Clinical trial: NCT02400970.
Cytogenetic aberrations are found in 65% of adults and 75% of children with acute leukemia. Specific aberrations are used as markers for the prognostic stratification of patients. The current ...standard cytogenetic procedure for acute leukemias is karyotyping in combination with FISH and RT-PCR. Optical genome mapping (OGM) is a new technology providing a precise identification of chromosomal abnormalities in a single approach. In our prospective study, the results obtained using OGM and standard techniques were compared in 29 cases of acute myeloid (AML) or lymphoblastic leukemia (ALL). OGM detected 73% (53/73) of abnormalities identified by standard methods. In AML cases, two single clones and three subclones were missed by OGM, but the assignment of patients to cytogenetic risk groups was concordant in all patients. OGM identified additional abnormalities in six cases, including one cryptic structural variant of clinical interest and two subclones. In B-ALL cases, OGM correctly detected all relevant aberrations and revealed additional potentially targetable alterations. In T-ALL cases, OGM characterized a complex karyotype in one case and identified additional abnormalities in two others. In conclusion, OGM is an attractive alternative to current multiple cytogenetic testing in acute leukemia that simplifies the procedure and reduces costs.
With the introduction of array comparative genomic hybridization (aCGH) techniques in the diagnostic setting of patients with developmental delay and congenital malformations, many new microdeletion ...syndromes have been recognized. One of these recently recognized microdeletion syndromes is the 16p11.2 deletion syndrome, associated with variable clinical outcomes including developmental delay, autism spectrum disorder, epilepsy, and obesity, but also apparently normal phenotype. We report on a 16-year-old patient with developmental delay, exhibiting retinis pigmentosa with progressive visual failure from the age of 9 years, ataxia, and peripheral neuropathy. Chromosomal microarray analysis identified a 1.7-Mb 16p11.2 deletion encompassing the 593-kb common deletion (∼29.5 to ∼30.1 Mb; Hg18) and the 220-kb distal deletion (∼28.74 to ∼28.95 Mb; Hg18) that partially included the CLN3 gene. As the patient's clinical findings were different from usual 16p11.2 microdeletion phenotypes and showed some features reminiscent of juvenile neuronal ceroid-lipofuscinosis (JNCL, Batten disease, OMIM 204200), we suspected and confirmed a mutation of the remaining CLN3 allele. This case further illustrates that unmasking of hemizygous recessive mutations by chromosomal deletion represents one explanation for the phenotypic variability observed in chromosomal deletion disorders.
Genetic instability plays an important role in ovarian carcinogenesis. We investigated the level of telomere shortening and genomic instability in early and preinvasive stages of ovarian cancer, ...serous tubal intraepithelial carcinoma (STIC), and tubo-ovarian dysplasia (TOD).
Fifty-one TOD from prophylactic salpingo-oophorectomies with BRCA1 or 2 mutation, 12 STICs, 53 tubo-ovarian high-grade serous carcinoma, and 36 noncancerous controls were laser capture microdissected from formalin-fixed, paraffin-embedded sections, analyzed by comparative genomic hybridization (array CGH) and for telomere length (using quantitative real-time PCR based on the Cawthon's method). TOD and STICs were defined by morphologic scores and immunohistochemical expressions of p53, Ki67, and γH2AX.
TOD showed marked telomere shortening compared with noncancerous controls (P < 10(-7)). STICs had even shorter telomeres than TOD (P = 0.0008). Ovarian carcinoma had shorter telomeres than controls but longer than STICs and dysplasia. In TOD, telomeres were significantly shorter in those with BRCA1 mutation than in those with BRCA2 mutation (P = 0.005). In addition, γH2AX expression in TOD and STIC groups with short telomeres was significantly increased (P < 10(-7)). In dysplastic epithelium, we found subtle genomic alterations, in contrast to more important genomic imbalances in STICs. The total number of genetic alterations was the highest in ovarian cancers.
These findings suggest that genetic instability occurs in early stages of ovarian tumorigenesis. STICs and noninvasive dysplasia are likely an important step in early serous ovarian neoplasia.
Correlations were reported between sperm telomere length (STL) and male fertility, sperm DNA fragmentation, and oxidation. Sperm freezing is widely used for assisted reproductive techniques, ...fertility preservation, and sperm donation. However, its impact on STL remains unknown. For this study, semen surplus from patients who underwent routine semen analysis were used. The impact of slow freezing on STL was analyzed by performing qPCR before and after freezing. Sperm populations with different STL were evaluated using Q-FISH. The relationship between sperm DNA oxidation, DNA fragmentation, and STL was assessed in fresh and frozen sperm samples. No significant impact of slow freezing on STL was observed, neither measured by qPCR nor Q-FISH. However, Q-FISH allowed for the distinguishing of sperm populations with different STLs within individual sperm samples. Slow freezing induced different STL distributions for some of the analyzed sperm samples, but no correlation was found between STL and sperm DNA fragmentation or oxidation. Slow freezing does not alter STL despite increasing sperm DNA oxidation and fragmentation. As STL alterations could be transmitted to offspring, the lack of impact of the slow freezing method on STL ensures the safety of this procedure.
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