Zeynab Mori, I can say that TCGA (The Cancer Genome Atlas) is a valuable resource for cancer genomics research. The database contains large-scale genomic and clinical data on over 30 types of cancer, and it is publicly available to researchers worldwide.

To access TCGA data, you typically need to register for an account and obtain an authorized access key. Once you have the access key, you can use it to download the data from the TCGA data portal.

Regarding the FASTQ files from the TCGA database, it is possible that the files you are trying to access are restricted to authorized users only. In that case, you may need to apply for access to the files by submitting a data access request through the TCGA data portal. The process may require additional documentation and approval from the TCGA Data Access Committee.

I suggest contacting the TCGA helpdesk for further information and assistance with accessing the FASTQ files. They can provide you with specific instructions and guidance on how to proceed.