Amplification of the 12q13-15 region is a common event in several human tumors including liposarcomas, gliomas, and osteosarcomas. We have demonstrated high-level amplification of 12q14 in a subset of uncultured malignant melanomas (3 of 53). High-resolution mapping of the amplicon using quantitative PCR revealed a bipartite amplicon consisting of a primary 50-kb amplicon centered on CDK4 and a secondary amplicon centered on MDM2, without amplification of the intervening 11 Mb of genomic DNA. Analysis of mRNA and protein levels in melanomas with 12q14 amplification demonstrated overexpression of target genes CDK4 and MDM2 without loss of CDKN2A-P16 (P16INK4A) or CDKN2A-P14ARF (P14ARF) expression, important regulators of the RB1 and TP53 pathways, which are commonly lost or mutated in melanoma. These results suggest that coamplification of CDK4 and MDM2 may substitute for loss of P16INK4A and P14ARF function in a subset of melanomas.

Download full-text PDF

Source
http://dx.doi.org/10.1002/gcc.20310DOI Listing

Publication Analysis

Top Keywords

cdk4 mdm2
12
amplicon centered
8
amplification
5
amplification cdk4
4
mdm2
4
mdm2 malignant
4
malignant melanoma
4
melanoma amplification
4
amplification 12q13-15
4
12q13-15 region
4

Similar Publications

There has been noteworthy progress in molecular characterisation and therapeutics in soft tissue sarcomas. Novel agents have gained regulatory approval by the FDA. Examples are the tyrosine kinase inhibitors avapritinib and ripretinib in gastrointestinal stromal tumours (GIST), the immune check point inhibitor atezolizumab in alveolar soft part tissue sarcoma, the γ-secretase inhibitor nirogacestat in desmoid tumours, the NTRK inhibitors larotrectinib and entrectinib in tumours with fusions, the mTOR inhibitor nab-sirolimus in PEComa, and the EZH-2 inhibitor tazemetostat in epithelioid sarcoma.

View Article and Find Full Text PDF

A male in his seventies presented with lung cancer in the right lower lobe. The surgically resected specimen revealed a pleomorphic carcinoma featuring an adenocarcinoma component with lepidic, acinar, and papillary patterns, alongside a spindle cell component spreading along the pulmonary artery wall, resembling intimal sarcoma. The spindle tumor cells were positive for keratins, TTF-1, napsin A, and vimentin, but negative for p40, CK14, desmin, alpha-smooth muscle actin, CDK4, and MDM2.

View Article and Find Full Text PDF

Genomic profiling of intimal sarcoma reveals molecular subtypes with distinct tumor microenvironments and therapeutic implications.

ESMO Open

January 2025

Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea. Electronic address:

Background: Intimal sarcoma is a rare and aggressive soft-tissue sarcoma with limited treatment options. We explored genomic profiles of intimal sarcoma to uncover therapeutic implications.

Materials And Methods: We analyzed tumor tissues from patients with intimal sarcoma who visited the Seoul National University Hospital (SNUH) using whole-exome, whole-transcriptome, and clinical next-generation sequencing (NGS), integrated with intimal sarcoma NGS data from two public cohorts.

View Article and Find Full Text PDF

Targeting CDK2 to circumvent treatment resistance in HR breast cancer.

Trends Mol Med

December 2024

Cancer Signaling and Microenvironment Program, Fox Chase Cancer Center, Philadelphia, PA, USA. Electronic address:

Genetic and epigenetic defects of the p53 system have previously been associated with resistance to CDK4/6 inhibitors in women with HR breast cancer. Recent data from Kudo et al. demonstrate that CDK2-targeting agents may offer an effective strategy to circumvent such resistance by enforcing cellular senescence downstream of RBL2 dephosphorylation.

View Article and Find Full Text PDF

Embryonic-type neuroectodermal tumors (ENTs) arising from testicular germ cell tumors (GCTs) is a relatively common type of somatic transformation in GCTs with poor prognosis and limited therapeutic options, particularly when patients develop disease recurrence or metastasis. Knowledge of key events driving this transformation is limited to the paucity of comprehensive genomic data. We performed a retrospective database search in a CLIA- and CAP-certified laboratory for testicular GCT-derived ENTs that had previously undergone NGS-based comprehensive genomic profiling during the course of clinical care.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!