Cancer in childhood, adolescence, and young adults: a population-based study of changes in risk of cancer death during four decades in Norway

Antigen receptor therapy in bone metastasis via optimal control for different human life stages

In this work we propose a bone metastasis model using power law growth functions in order to describe the biochemical interactions between bone cells and cancer cells. Experimental studies indicate that bone remodeling cycles are different for human life stages: childhood, young adulthood, and adulthood. In order to include such differences in our study, we estimate the model parameter values for each human life stage via bifurcation analysis. Results reveal an intrinsic relationship between the active period of remodeling cycles and the proliferation of cancer cells. Subsequently, using optimal control theory we analyze a possible antigen receptor therapy as a new treatment for bone metastasis. Theoretical results such as existence of optimal solutions are proved. Numerical simulations for late stages of bone metastasis are presented and a discussion of our results is carried out.

miR-324-3p and miR-508-5p expression levels could serve as potential diagnostic and multidrug-resistant biomarkers in childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is one of the most frequent hematological malignancies in children, representing approximately 25 % of all pediatric cancers. Despite striking advances in ALL treatments, a small population of patients does not still respond to chemotherapy, raising the number of deaths in children. ABC transporters are one of the major causes of multidrug resistance (MDR) in cancers and overexpression of ABCA3 is directly associated with increased chemo-resistance in pediatric ALL. Here, we aimed to identify the microRNAs (miRNAs) which may regulate the expression of ABCA3 in childhood ALL. Bone marrow samples from a total of 50 ALLs and 59 controls were collected and after in silico and literature search, miR-324-3p and miR-508-5p were nominated from a list of putative miRNAs targeting ABCA3. Our qPCR analysis showed a low expression profile of selected miRNAs in pediatric ALL patients compared with non-cancer controls. Furthermore, we found that both miR-324-3p and miR-508-5p were significantly differentially expressed between patients with positive and negative minimal residual disease (MRD + vs MRD-) after one year of chemotherapy while only miR-508-5p was underexpressed in relapsed ALL patients. Additionally, a negative correlation was identified between the expression of these two miRNAs and ABCA3, supporting the regulatory effect of them on drug resistance through interacting with ABCA3. Overall, we suggested miR-324-3p and miR-508-5p as potential diagnostic and drug-resistant biomarkers in pediatric ALL. Moreover, our findings presented miR-508-5p to behave as a promising relapsed indicator in childhood ALL which can be applied in the development of novel therapeutic strategies.

"Feasible and effective administration of Bortezomib with Rituximab in children with relapsed/resistant B-cell precursor acute lymphoblastic leukemia (BCP-ALL): A step toward the first line"

Despite a high cure rate in childhood BCP-ALL, 20% of children still presents with relapse, mostly due to a persistent leukemic clone during the first-line treatment. In this context, obtaining a molecular remission is crucial for reaching a successful allogeneic hematopoietic stem cell transplantation. Bortezomib was effectively administered to children with resistant/relapsed (r/r) BCP-ALL. Moreover, high risk ALL is characterized by the increasing expression of CD20. For the first time we reported two children with r/r BCP-ALL who received a treatment schema including Bortezomib and Rituximab, achieving morphological and molecular remission. Children with high risk features, such as persistent minimal residual disease during induction, will benefit from this combination. Is it time to move toward the first line?

The cellular senescence of leukemia-initiating cells from acute lymphoblastic leukemia is postponed by β-Arrestin1 binding with P300-Sp1 to regulate hTERT transcription

Although we previously reported that the self-renewal of leukemia-initiating cells of B-lineage acute lymphoblastic leukemia (B-ALL LICs) was regulated by β-Arrestin1, a multiple-function protein, the cellular senescence is critical for LICs fate and leukemia progress, and worthy for further investigation. Here we found that depletion of β-Arrestin1 extended the population doubling time and the percentage of senile cells, the signatures of cellular senescence, of B-ALL LICs. Moreover, lack of β-Arrestin1 enhanced the expression of proteins (CBX, HIRA) and genes (P53, P16) related to senescence in leukemic Reh cells and B-ALL-LICs-derived leukemic mice. Further results showed that loss of β-Arrestin1 induced senescence of Reh cells through mediating hTERT-telomerase-telomere axis, which was reversed by BIBR1532, the telomerase activity inhibitor. Importantly, depletion of β-Arrestin1 decreased the binding of Sp1 to hTERT promoter at the region of −28 to −36 bp. The anti-sense oligonucleotide of this key region downregulated the transcription of hTERT and aggravated the senescence of Reh cells. Further data demonstrated that the depleted β-Arrestin1 reduced the interaction of P300 with Sp1, thus to reduce Sp1 binding to hTERT promoter, downregulate hTERT transcription, decrease telomerase activity, shorten telomere length, and promote Reh cell senescence. Interestingly, the percentage of senile cells in B-ALL LICs was decreased, which was negatively correlated to good prognosis and β-Arrestin1 mRNA expression in childhood B-ALL patients. Our study shed a light on the senescence of B-ALL LICs and is regulated by β-Arrestin1, providing the potential therapeutic target of leukemia by promoting cellular senescence with a key region of hTERT promoter.

Childhood relapsed acute lymphoblastic leukemia: Biology and recent treatment progress

Acute lymphoblastic leukemia (ALL) is the most frequent cancer in children. Despite remarkable improvement in the prognosis of childhood ALL over the past few decades, the treatment of relapsed ALL is still challenging. The prognosis of first ALL relapse is associated with time of relapse after initial therapy, sites of relapse, and immunophenotype. More recently, response to treatment, which is evaluated by assessment of minimal residual disease (MRD), has been found to be clinically significant in relapsed ALL as well as in the initially diagnosed disease. Utilizing these factors, risk-oriented treatment stratification for first ALL relapse has been established. In the standard-risk group for first ALL relapse, intensification of conventional ALL-type therapy can provide a cure in approximately 70% of patients. It is important to assess MRD after reinduction therapy to determine the indications for stem cell transplantation in the standard-risk group. In contrast, no standardized therapy has been established for the high-risk group, which accounts for more than half of relapsed ALL patients. Recent studies have shed light on the clonal origin of relapsed ALL, which usually exists as a minor subclone at the time of initial diagnosis. Clonal selection and evolution take place during chemotherapy, resulting in distinct genetic and epigenetic characteristics of relapsed ALL, some of which are linked to drug resistance, a common and problematic feature of ALL after relapse. To overcome resistance to standard ALL-type therapy, and considering the heterogeneous biological background of high-risk relapsed ALL, innovative therapies using new agents are necessary.

Educational attainment among long-term survivors of cancer in childhood and adolescence: a Norwegian population-based cohort study

PURPOSE

The number of young cancer survivors has increased over the past few decades due to improvement in treatment regimens, and understanding of long-term effects among the survivors has become even more important. Educational achievements and choice of educational fields were explored here.

METHODS

Five-year cancer survivors born in Norway during 1965-1985 (diagnosed <19 years) were included in our analysis by linking Norwegian population-based registries. Cox regression was applied to study the educational attainment among survivors of central nervous system (CNS) tumours, those assumed to have received CNS-directed therapy, and other cancer survivors relative to the cancer-free population. Logistic regression was used to compare the choice of educational fields between the cancer survivors at undergraduate and graduate level and the cancer-free population.

RESULTS

Overall, a lower proportion of the cancer survivors completed intermediate (67 vs. 70 %), undergraduate (31 vs. 35 %) and graduate education (7 vs. 9 %) compared with the cancer-free population. Deficits in completion of an educational level were mainly observed among survivors of CNS-tumours and those assumed to have received CNS-directed therapy. Choices of educational fields among cancer survivors were in general similar with the cancer-free population at both undergraduate and graduate levels.

CONCLUSION

Survivors of CNS-tumours and those assumed to have received CNS-directed therapy were at increased risk for educational impairments compared with the cancer-free population. Choices of educational fields were in general similar.

IMPLICATIONS FOR CANCER SURVIVORS

Careful follow-up of the survivors of CNS-tumours and those assumed to have received CNS-directed therapy is important at each level of education.

Increased uptake of social security benefits among long-term survivors of cancer in childhood, adolescence and young adulthood: a Norwegian population-based cohort study

BACKGROUND

As the number of cancer survivors increases, their health and welfare have come into focus. Thus, long-term medical consequences of cancer at a young age (<25 years), obtained from social security benefit records, were studied.

METHODS

Standardised incidence ratios (SIRs) of long-term medical consequences for 5-year cancer survivors, born during 1965-1985, were explored by linking population-based registries in Norway.

RESULTS

Among the 5-year cancer survivors (4031 individuals), 29.7% received social security benefits. The survivors had an overall 4.4 times (95% confidence interval (95% CI): 4.1-4.6) higher risk of social security benefit uptake than the cancer-free population. Survivors of malignancies of bone and connective tissues (SIR: 10.8; 95% CI: 9.1-12.9), CNS tumours (SIR: 7.7; 95% CI: 6.9-8.6) and malignancies of the haematopoietic system (SIR: 6.1; 95% CI: 5.3-7.0) had the highest risks of social security benefits uptake. The most notified causes of social security benefit uptake were diseases of the nervous system, and injury and poisoning.

CONCLUSION

The uptake of social security benefits among 5-year cancer survivors increased substantially and it may represent a solid outcome measure for the burden of the most severe late effects, especially in countries with comparable social welfare systems.