Diagnostic, prognostic and predictive values of miR-100 and miR-210 in pediatric acute lymphoblastic Leukemia

BACKGROUND

: microRNAs are playing important roles in the diagnosis and prognosis of pediatric acute lymphoblastic leukemia (ALL).

METHODS

Expression levels of miR-100 and miR-210 were assessed in bone marrow aspirate of 85 pediatric ALL patients compared to 12 healthy control using quantitative real-time polymerase chain reaction. Data were correlated with relevant clinico-pathological features of the patients, response to treatment, disease-free survival (DFS), and overall survival (OS).

RESULTS

miR-100 was significantly downregulated in ALL patients [median: 1.21, range: 0-434.3] compared to the control group [median: 8.41, range; 0-840.3, P = 0.035]. miR-210 was significantly upregulated in ALL patients [median: 6.34, range: 1.16-1088.7] compared to the control group [median: 2.57, range: 0.11-709.2, P  = 0.025]. The sensitivity, specificity, and area under curve of miR-100 were (64.7%, 62.5%, and 0.642; respectively, P = 0.035) at a cut-off 2.6 and that of miR-210 were (60%, 58.3% and 0.650; respectively, P = 0.025) at a cut-off 3.5. miR-100 overexpression associated with shorter DFS and OS (P = 0.033 and 0.046; respectively). Patients with miR-100 lowexpression showed a significant incidence of late death ( P = 0.024). There was no significant association between miR-210 expression and DFS, OS, incidence of early or late death.

CONCLUSION

: miR-100 and miR-210 could be used as potential diagnostic markers for pediatric ALL. miR-100 is a useful prognostic and predictive biomarker for childhood ALL.

Immunohistological characterisation of tumour infiltrating lymphocytes in melanocytic skin lesions

BACKGROUND

Although the presence of tumour infiltrating lymphocytes (TIL) is a constant feature in melanomas, their immunophenotypic characterisation is still incomplete. We hypothesise that the transition from normal skin to benign naevi (BN) to melanocytic dysplastic naevi (MDN) to radial growth phase cutaneous malignant melanoma (RGP-CMM) to vertical growth phase cutaneous malignant melanoma (VGP-CMM) is associated with alterations in TIL. This study attempted to test this hypothesis and to characterise TIL in the melanocytic skin lesions.

METHODS

In total, 74 lesions (12 BN, 12 MDN, 13 RGP-CMM, 26 VGP-CMM, and 11 metastatic melanomas) were examined using immunoperoxidase staining methods and antibodies targeting leukocyte common antigen (LCA+), T (CD3+) and B (CD20+) lymphocytes, and resting cytotoxic T cells (TIA-1+).

RESULTS

Histologically, the transitions from normal skin to BN to MDN to RGP-CMM to VGP-CMM was associated with a gradual increase in the numbers of TIL (total, parenchymal, stromal, perivascular, and epidermal TIL, as well as TIL at the base of the lesions). The numbers of TIL were higher at the stroma than at the parenchyma. Similarly, immunostaining revealed that these transitions were associated with a gradual increase in the staining values (staining intensity, percentage of positive cells, and immunoreactivity score) for LCA+, CD20+, CD3+, and TIA-1+cells. The number of CD3+ cells was higher than that of CD20+ cells. All these differences between the normal skin and the lesional ones reached statistical significance (p<0.01). The majority of CD3+ cells were TIA-1+ T cells with cytotoxic potential. Compared with primary melanomas, there was a decrease in TIL in metastatic melanomas.

CONCLUSIONS

The gradual increase in TIL during melanoma tumorigenesis may reflect increased antigenicity of the tumour cells. Although both humoral and cell mediated immunity are involved in melanomagenesis, the latter seems to have the major role. The immune profile of MDN suggests their intermediacy between BN and CMM.

T cell immunity in neonates

Typically, neonates exhibit decreased or aberrant cellular immune responses when compared to adults, resulting in increased susceptibility to infection. However, it is clear that newborns are able to generate adult-like protective T cell responses under certain conditions. The focus of our research is to understand the deficiencies within the neonatal immune system that lead to improper cellular responses and how priming conditions can be altered to elicit the appropriate T cell response necessary to protect against development of pathogen-induced disease. With these goals in mind, we are exploring the attributes of neonatal T cells and their development, as well as the conditions during priming that influence the resulting response to immune challenge during the neonatal period.