Malignant melanoma in Portuguese adult population: a scoping review of the real-world evidence.

PURPOSE: Malignant melanoma is an aggressive cancer, and there is a notable dearth on epidemiology, clinical and treatment characterization within the Portuguese population. We performed a scoping review to identify real-world evidence studies focused in Portuguese adult patients with malignant melanoma. METHODS: A comprehensive search was conducted. After screening, we described the studies by design, sample size, geographics, setting, population, and outcomes reported. RESULTS: The search yielded 54 studies, mainly retrospective (79.6%). The population assessed was heterogeneous varying from patients with melanoma in general to specific types of melanoma, or even more restricted to patients with specific conditions. The evidence found was mostly concerning clinical outcomes (n=46), patients' clinical profile (n=44) and demographic characterization (n=48). Treatment information was described in 30 studies whereas only 18 reported epidemiological parameters. Studies were mainly performed by the major oncology centers in Lisbon, Oporto and Coimbra, and only two evaluated the entire Portuguese population. To allow comparability, only studies including patients with cutaneous malignant melanoma were considered (13 of the 54) for outcomes evaluation analysis. Median OS varied from 18 to 36 months, assessed after melanoma treatment. Incidence was the most reported epidemiological parameter, confirming the increasing number of cutaneous malignant melanoma patients over the years. Only one study reported prevalence and four reported mortality rates. CONCLUSIONS: The evidence found confirms the lack of information about malignant melanoma in Portugal, highlighting the need of real-world studies to assess melanoma prevalence and incidence rates, current treatment approaches, and clinical characterization of these patients.

CASZ1 upregulates PI3K-AKT-mTOR signaling and promotes T-cell acute lymphoblastic leukemia.

CASZ1 is a conserved transcription factor involved in neural development, blood vessel assembly and heart morphogenesis. CASZ1 has been implicated in cancer, either suppressing or promoting tumor development depending on the tissue. However, the impact of CASZ1 on hematological tumors remains unknown. Here, we show that the T-cell oncogenic transcription factor TAL1 is a direct positive regulator of CASZ1, that T-cell acute lymphoblastic leukemia (T-ALL) samples at diagnosis overexpress CASZ1b isoform, and that CASZ1b expression in patient samples correlates with PI3KAKT- mTOR signaling pathway activation. In agreement, overexpression of CASZ1b in both Ba/F3 and T-ALL cells leads to the activation of PI3K signaling pathway, which is required for CASZ1b-mediated transformation of Ba/F3 cells in vitro and malignant expansion in vivo. We further demonstrate that CASZ1b cooperates with activated NOTCH1 to promote T-ALL development in zebrafish, and that CASZ1b protects human T-ALL cells from serum deprivation and treatment with chemotherapeutic drugs. Taken together, our studies indicate that CASZ1b is a TAL1-regulated gene that promotes T-ALL development and resistance to chemotherapy.

The multiple layers of non-genetic regulation of PTEN tumour suppressor activity.

Mutations and deletions of the tumour suppressor phosphatase and tensin homologue deleted on chromosome 10 (PTEN) are frequently involved in the development of cancer. However, PTEN is also tightly controlled by various non-genomic mechanisms. This review focuses on those mechanisms, namely on the epigenetic silencing of PTEN, post-transcriptional regulation by non-coding RNAs and post-translational modification. We summarise their involvement in cancer in general, and place some emphasis on leukaemia, where PTEN genetic lesions are relatively uncommon and, strikingly, high levels of PTEN expression frequently associate with PTEN functional inactivation. Overall, it is apparent that rather than looking strictly for PTEN genetic lesions and PTEN expression status, the key to evaluating the real impact of PTEN as a 'quasi-insufficient' tumour suppressor must rely on the complete understanding of PTEN's 'functional dose', incorporating the multiple layers of PTEN regulation in the cell that are ultimately compromised in a given cancer.

Erk5 is activated and acts as a survival factor in mitosis.

Erk5 is a recently discovered MAPK claimed to be responsible for some of the roles attributed to Erk1/2; here we report that it is activated in mitosis in comparison to G1/S. When Erk5 is inactivated pharmacologically or largely ablated by RNAi, cell survival in mitosis is diminished. We have previously shown Bim, a BH3-only protein of the Bcl-2 family, to be phosphorylated in mitosis, in a MEK-dependent manner (M. Grãos, A. D. Almeida, S. Chatterjee, Biochem. J. 388 (2005) 185). Inactivation of Erk5 in mitosis causes dephosphorylation of Bim. Bim is in the mitochondria in mitosis and when dephosphorylated interacts with Bax, inducing caspase activation. We also show that in mitosis Bim co-immunoprecipitates with Erk5 and Erk5 phosphorylates GST-Bim in in vitro kinase reaction. Taken together, our results identify a new target of the still largely mysterious Erk5 and suggest that Erk5 in mitosis may be a decisive step for the survival of proliferating cells.