Ann Lab Med.  2021 Jul;41(4):409-413. 10.3343/alm.2021.41.4.409.

Phospholipase C Beta 2 Protein Overexpression Is a Favorable Prognostic Indicator in Newly Diagnosed Normal Karyotype Acute Myeloid Leukemia

• Park MS
• Lee YE
• Kim HR
• Shin JH
• Cho HW
• Lee JH
• Shin MG

• KMID: 2512721
• DOI: http://doi.org/10.3343/alm.2021.41.4.409

Abstract

Phospholipase C beta 2 (PLC-β2) regulates various essential functions in cell signaling, differentiation, growth, and mobility. We investigated the clinical implications of PLC-β2 protein expression in newly diagnosed normal karyotype acute myeloid leukemia (NKAML). The PLC-β2 expression status in bone marrow tissues obtained from 101 patients with NK-AML was determined using semiquantitative immunohistochemistry (IHC). IHC results were compared with those for known prognostic markers. Using a cutoff score for positivity of 7.0, the PLC-β2 overexpression group showed superior overall survival (OS) (72.6% vs. 26.5%; P = 0.016) and low hazard ratio (HR) (0.453; P = 0.019) compared with the PLC-β2 low-expression group. The PLC-β2 overexpression group showed no significant gain in event-free survival (50.6% vs. 43.0%, P =0.465) and HR (0.735; P =0.464). Among the known prognostic markers, only FLT3-ITD positivity was associated with a significantly low OS and high HR. In conclusion, PLC-β2 overexpression was associated with favorable OS in NK-AML patients. Our results suggest that PLC-β2 expression assessment using IHC allows prognosis prediction in NK-AML.

Keyword

Phospholipase C beta 2 protein; normal karyotype acute myeloid leukemia; prognosis

Figure

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  Fig. 1 Clinicopathological implications of PLC-β2 protein expression in NK-AML patients. (A) Overall survival of NK-AML patients based on PLC-β2 expression status using Kaplan–Meier analysis. NK-AML patients with PLC-β2 overexpression (IHC score ≥7) presented significantly longer overall survival, indicating that PLC-β2 serves as a good prognostic marker. (B) Hazard ratio and overall survival of NK-AML patients according to various prognostic factors. PLC-β2 protein is a good prognostic indicator, whereas FLT3-ITD variants are poor prognostic markers. Each hazard ratio was specified as an unadjusted hazard ratio by univariate analysis. Abbreviations: PCL, phospholipase C; NK-AML, normal karyotype acute myeloid leukemia; IHC, immunohistochemistry; NPM1, nucleophosmin 1 gene; FLT3-ITD, FLT3 internal tandem duplication gene; WT1, Wilm’s tumor suppressor gene 1; BAALC, brain and acute leukemia, cytoplasmic gene.

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