ABSTRACT
Ovarian clear cell carcinoma (OCCC) is often considered a relatively platinum-resistant malignancy. The aim of this study was to explore the influence of progesterone receptor (PR) expression levels on platinum sensitivity and survival outcomes in people with OCCC. A retrospective analysis was conducted with 80 people with OCCC who underwent surgery followed by adjuvant chemotherapy. PR expression was assessed via immunohistochemical (IHC) staining and quantified using the H score. The platinum sensitivity and survival outcomes of patients with weak and strong PR expression were compared. Additionally, cisplatin viability and migration experiments were conducted with OCCC cell lines (ES-2 and TOV-21G) with varying PR isoform expressions. Among the 80 patients, 62 were classified as having platinum-sensitive disease, while 18 had platinum-resistant disease. The mean total PR H- score of platinum-sensitive tumors was significantly higher than that of platinum-resistant tumors (p = 0.002). Although no significant differences in progression-free and overall survival were observed between patients with high and low PR expression, those with high PR expression tended to have longer survival. While PR protein was only weakly detectable in ES-2 and TOV-21G cells, a transfection of the PR-A or PR-B gene resulted in a strong expression of PR-A or PR-B, which led to significantly reduced proliferation and migration in ES-2 and TOV-21G cells. Furthermore, overexpression of PR-A or PR-B enhanced cisplatin cytotoxicity in these cell lines. In conclusion, strong PR expression was associated with improved platinum sensitivity and survival outcomes, consistent with our experimental findings. The potential of PR as a tumor sensitizer to cisplatin in OCCC warrants further investigation.
Subject(s)
Adenocarcinoma, Clear Cell , Cisplatin , Drug Resistance, Neoplasm , Ovarian Neoplasms , Receptors, Progesterone , Humans , Female , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Receptors, Progesterone/metabolism , Receptors, Progesterone/genetics , Middle Aged , Adenocarcinoma, Clear Cell/metabolism , Adenocarcinoma, Clear Cell/drug therapy , Adenocarcinoma, Clear Cell/pathology , Adenocarcinoma, Clear Cell/genetics , Drug Resistance, Neoplasm/genetics , Cisplatin/pharmacology , Cisplatin/therapeutic use , Cell Line, Tumor , Aged , Adult , Retrospective Studies , Cell Movement/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Platinum/pharmacology , Platinum/therapeutic use , Gene Expression Regulation, Neoplastic/drug effectsABSTRACT
OBJECTIVE: Acral lentiginous melanoma is the most common subtype of cutaneous melanoma in Asian countries. This study aims to clarify the associations between certain histologic and immunohistochemical parameters, and identify their prognostic values. METHODS: We assessed several histologic features and conducted immunohistochemical study of programmed cell death ligand 1 (clone 22C3) and CD8/CD4 in 61 Taiwanese patients with Stage III/IV, non-BRAF acral lentiginous melanomas. RESULTS: A total of 41 males and 20 females were included, with a median age of 74 years. The majority of tumors occurred at nonungual locations (86.9%), with 'foot' being the most frequently affected site (85.2%). Positive programmed cell death ligand 1 staining (combined positive score ≥ 10) was significantly associated with the status of tumor-infiltrating lymphocytes (P = 0.036). Lack of skin ulceration was linked to the immunoexpression of CD8/CD4-high (P = 0.004). A superior clinical outcome was found in the tumor-infiltrating lymphocytes-present group (P = 0.011), and among which, CD8/CD4-high was significantly correlated with better survival (P < 0.001). Combined survival analysis revealed that the PD-L1(-) TIL(+) CD8/CD4-high subgroup was associated with favorable prognosis, and cases with PD-L1(+) TIL(-) showed the worst disease specific survival (P < 0.001). In the univariate analysis, lymphovascular invasion (P = 0.002), skin ulceration (P = 0.002), tumor-infiltrating lymphocytes (P = 0.015) and CD8/CD4 status (P < 0.001) were significant prognostic factors. At the multivariate level, the statuses of CD8/CD4-low (P < 0.001) and lymphovascular invasion (P = 0.014) represented the independent poor prognosticators. CONCLUSION: For advanced, non-BRAF acral lentiginous melanomas, comprehensive assessments of these microscopic traits, along with CD8/CD4 and PD-L1 immunoprofiles, may help guide the clinicians and patients through treatment decisions.
Subject(s)
Melanoma , Skin Neoplasms , Aged , B7-H1 Antigen/metabolism , CD8-Positive T-Lymphocytes , Female , Humans , Ligands , Male , Melanoma/pathology , Prognosis , Melanoma, Cutaneous MalignantABSTRACT
Previous studies have suggested that cancer stem cells (CSCs) resisted radiotherapy and chemotherapy. P16INK4A is a biomarker for cervical carcinogenesis and reduces proliferation of stem cells. We aimed to investigate the expression and clinical significance of cyclin-dependent kinase inhibitor 2A (P16INK4A), sex determining region Y-box 2 (SOX2), and Aldehyde dehydrogenase 1 family, member A1 (ALDH1A1) in cervical cancer treated with radiotherapy and cervical cell line models. The expressions of P16INK4A, SOX2, and ALDH1A1 were performed by immunohistochemical staining of tumor samples from 139 cervical cancer patients with International Federation of Gynecology and Obstetrics stages Ib to IV. The staining showed high expression in 100, 107, and 13 patients with P16INK4A (>80%), SOX2 (≥10%), and ALDH1A1 (50%), respectively. The high-P16INK4A group had a higher five-year overall survival (OS) rate and disease-free survival (DFS) than the low-P16INK4A group (OS: 62.0% and 35.2%, p = 0.016; DFS: 60.0% and 31.2%, p = 0.002). The low-P16INK4A/high-SOX2 and low-P16INK4A/high-ALDH1A1 groups had a worse five-year OS and DFS rate than the high-P16INK4A/low-SOX2 and high-P16INK4A/low-ALDH1A1 groups, respectively. Depletion of P16INK4A promoted chemoresistance and radioresistance of cervical cancer cells increased the expression of SOX2 and ALDH1A1 and exhibited higher self-renewal ability. These results suggest that lower P16INK4A expression associated with higher CSC markers predicts poor prognostic outcomes and is a promising target in patients with cervical cancer.
Subject(s)
Biomarkers, Tumor/biosynthesis , Cyclin-Dependent Kinase Inhibitor p16/biosynthesis , Neoplastic Stem Cells/radiation effects , Uterine Cervical Neoplasms/radiotherapy , Aldehyde Dehydrogenase/biosynthesis , Aldehyde Dehydrogenase/genetics , Aldehyde Dehydrogenase 1 Family , Biomarkers, Tumor/genetics , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor p16/genetics , Disease-Free Survival , Female , Gene Expression Regulation, Neoplastic , HeLa Cells , Humans , Immunohistochemistry , Middle Aged , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology , Prognosis , Retinal Dehydrogenase , SOXB1 Transcription Factors/biosynthesis , SOXB1 Transcription Factors/genetics , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/metabolismABSTRACT
AIMS: Solitary fibrous tumour (SFT) harbours recurrent inv12(q13q13)-derived NAB2-STAT6 fusions, resulting in STAT6 nuclear expression. SFTs affecting the head and neck are rare, for which we reported their clinicopathological, immunohistochemical, and genetic features. METHODS AND RESULTS: With 19 cases assessable for NAB2-STAT6 fusions, 36 head and neck SFTs (18 males; 18 females) diagnosed between 13 and 79 years (median, 47 years) of age were analysed for clinicopathological features and STAT6 immunoexpression. These SFTs, ranging from 5 to 80 mm (median, 25 mm), affected the oral cavity/pharynx (12), orbit (11), sinonasal structures (seven), and somatic soft tissues or skull (six). Histologically, 20 SFTs were conventional, six were giant-cell angiofibroma-like, one was fat-forming, four were cellular/atypical, and five were malignant (two developing metastases). STAT6 distinctively decorated the tumoral nuclei in 35 (97.2%) SFTs, but not in 29 site-relevant histological mimics categorized into 12 entities. Sixteen (84.2%) SFTs showed NAB2-STAT6 fusions with highly heterogeneous exon compositions, including NAB2ex6-STAT6ex17 in four cases, NAB2ex4-STAT6ex2 in three cases, NAB2ex2-STAT6ex2, NAB2ex4-STAT6ex4, NAB2ex6-STAT6ex16 and NAB2ex6-STAT6ex18 in two cases each, and NAB2ex3-STAT6ex19 in one case. CONCLUSIONS: Nuclear STAT6 immunoexpression is sensitive and specific for distinguishing SFT from mimics. However, considerable heterogeneity exists in the head and neck SFTs regarding the locations, histological patterns, and NAB2-STAT6 fusion variants.
Subject(s)
Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/pathology , Repressor Proteins/genetics , STAT6 Transcription Factor/genetics , Solitary Fibrous Tumors/genetics , Solitary Fibrous Tumors/pathology , Adolescent , Adult , Aged , Biomarkers, Tumor/analysis , Cell Nucleus/metabolism , Diagnosis, Differential , Female , Humans , Immunohistochemistry , Male , Middle Aged , Oncogene Proteins, Fusion/biosynthesis , Oncogene Proteins, Fusion/genetics , Reverse Transcriptase Polymerase Chain Reaction , STAT6 Transcription Factor/biosynthesis , Young AdultABSTRACT
Solitary fibrous tumor (SFT) is a rare mesenchymal neoplasm harboring NAB2-STAT6 fusion, which drives STAT6 nuclear relocation. For extrathoracic SFTs, the clinical relevance of this molecular hallmark remains obscure. We assessed STAT6 immunoexpression for 61 extrathoracic SFTs exclusive of the meninges and head and neck, and 25 had analyzable RNAs to distinguish fusion variants by RT-PCR. The immunohistochemical and molecular findings were correlated with clincopathological features and disease-free survival (DFS). Twenty-eight males and 33 females had SFTs in the body cavities (n = 31), extremities (n = 17), and trunk (n = 13), categorized into 53 non-malignant and 8 malignant tumors. The vast majority (n = 57, 93%) exhibited distinctive STAT6 nuclear expression, including malignant ones. The common fusion variants were NAB2ex6-STAT6ex16/17 in 13 SFTs and NAB2ex4-STAT6ex2 in 8, while miscellaneous variants were detected only in 4 SFTs in the limbs and trunk but not in any body cavity-based cases (P = 0.026). The worse DFS was univariately associated with malignant histology (P = 0.04) but unrelated to tumor size, location, or fusion variant. Conclusively, extrathoracic SFTs mostly harbor NAB2ex6-STAT6ex16/17, followed by NAB2ex4-STAT6ex2. Miscellaneous variants are significantly rare in SFTs within the body cavities. The clinical aggressiveness of extrathoraic SFTs is associated with malignant histology but unrelated to the NAB2-STAT6 fusion variants.
Subject(s)
Oncogene Fusion/genetics , Repressor Proteins/genetics , STAT6 Transcription Factor/genetics , Soft Tissue Neoplasms/genetics , Solitary Fibrous Tumors/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/genetics , Female , Humans , Immunohistochemistry , Male , Middle Aged , Oncogene Proteins, Fusion/genetics , STAT6 Transcription Factor/metabolism , Soft Tissue Neoplasms/metabolism , Soft Tissue Neoplasms/pathology , Solitary Fibrous Tumors/metabolism , Solitary Fibrous Tumors/pathology , Young AdultABSTRACT
Solitary fibrous tumor (SFT) is characterized by the inv12(q13q13)-derived NAB2-STAT6 fusion, which exhibits variable breakpoints and drives STAT6 nuclear expression. The implications of NAB2-STAT6 fusion variants in pathological features and clinical behavior remain to be characterized in a large cohort of SFTs. We investigated the clinicopathological correlates of this genetic hallmark and analyzed STAT6 immunoexpression in 28 intrathoracic, 37 extrathoracic, and 23 meningeal SFTs. These 88 tumors were designated as histologically nonmalignant in 75 cases and malignant in 13, including 1 dedifferentiated SFT. Eighty cases had formalin-fixed and/or fresh samples to extract assessable RNAs for RT-PCR assay, which revealed NAB2-STAT6 fusion variants comprising 12 types of junction breakpoints in 73 fusion-positive cases, with 65 (89%) falling into 3 major types. The predominant NAB2ex4-STAT6ex2 (n=33) showed constant breakpoints at the ends of involved exons, whereas the NAB2ex6-STAT6ex16 (n=16) and NAB2ex6-STAT6ex17 (n=16) might exhibit variable breakpoints and incorporate NAB2 or STAT6 intronic sequence. Including 73 fusion-positive and 7 CD34-negative SFTs, STAT6 distinctively labeled 87 (99%) SFTs in nuclei, exhibited diffuse reactivity in 73, but did not decorate 98 mimics tested. In seven fusion-negative cases, 6 were STAT6-positive, suggesting rare fusion variants not covered by RT-PCR assay. Regardless of histological subtypes, intrathoracic SFTs affected older patients (P=0.035) and tended to be larger in size (P=0.073). Compared with other variants, NAB2ex4-STAT6ex2/4 fusions were significantly predominant in the SFTs characterised by intrathoracic location (P<0.001), older age (P=0.005), decreased mitoses (P=0.0028), and multifocal or diffuse STAT6 staining (P=0.013), but not found to correlate with disease-free survival. Conclusively, STAT6 nuclear expression was distinctive in the vast majority of SFTs, including all fusion-positive tumors, and exploitable as a robust diagnostics of CD34-negative cases. Despite the associations of NAB2-STAT6 fusion variants with several clincopathological factors, their prognostic relevance should be further validated in large-scale prospective studies of SFTs.
Subject(s)
Oncogene Proteins, Fusion/genetics , Repressor Proteins/genetics , STAT6 Transcription Factor/genetics , Solitary Fibrous Tumors/genetics , Solitary Fibrous Tumors/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Male , Middle Aged , Polymerase Chain Reaction , Solitary Fibrous Tumors/mortality , Young AdultABSTRACT
Introduction: To investigate the role of tumor galectin-1 and galectin-3 in patients with lung adenocarcinoma after definitive radiation therapy. Methods: A total of 41 patients with localized lung adenocarcinoma undergoing thoracic radiation therapy without concurrent chemotherapy were enrolled. Their paraffin-embedded lung tissues were sent for immunohistochemical staining for galectin-1 and galectin-3. The clinical treatment outcomes, including overall (OS), locoregional progression-free (LRPFS), and distant metastasis-free (DMFS) survivals, were evaluated. Univariable and multivariable Cox regression analyses were applied. Results: Overexpression of tumor galectin-1 and galectin-3 were found in 26.8% and 19.5% of patients, respectively. Overexpression of tumor galectin-1 was the most significant prognosticator to predict worse LRPFS in both univariable (p = 0.007) and multivariable analyses (p = 0.022). Besides, patients with overexpression of tumor galectin-1 had a trend of worse OS (p = 0.066) than those with low expression in multivariable analysis, and worse DMFS (p = 0.035) in univariable analysis. The overexpression of tumor galectin-3 had no significant effect on survival outcomes. Conclusions: The overexpression of tumor galectin-1, but not galectin-3, is associated with poor LRPFS of patients with lung adenocarcinoma after thoracic radiation therapy. Future research on the mechanism of galectin-1 affecting radiation response in lung adenocarcinoma may be worth exploring.
ABSTRACT
BACKGROUND: Expression of the progesterone receptor (PR) has been reported to influence survival outcomes in patients with ovarian high-grade serous carcinoma (HGSC). In the present study, we attempted to investigate the association among PR and its isoforms' expression, platinum sensitivity, and survival in ovarian HGSC. MATERIAL AND METHODS: This retrospective study reviewed ovarian HGSC patients who received surgery followed by adjuvant chemotherapy. We analyzed total PR and PR isoform-B (PR-B) expression by immunohistochemical staining and quantified using the H-score. Then, we compared platinum sensitivity and survival outcomes between those patients with weak and strong PR-B expression. Cisplatin viability assays were carried out in ovarian HGSC cell lines (OC-3-VGH and OVCAR-3) with different PR-B expression. RESULTS: Among 90 patients, 49 and 41 patients were considered to have platinum-sensitive and platinum-resistant disease, respectively. Pearson's correlation model showed that the H-score of total PR correlated positively with PR-B (r = 0.813). The PR-B H-score of tumors was significantly higher in the platinum-sensitive group (p = 0.004). Multivariate analysis revealed that the PR-B H-score and optimal debulking status were independent factors predicting platinum sensitivity. When compared with strong PR-B expression, patients with weak PR-B had significantly poorer progression-free (p = 0.021) and cancer-specific survival (p = 0.046). In a cell model, cisplatin-resistant OC-3-VGH cells expressed a lower level of PR-B than wild-type cells. Overexpression of PR-B or progesterone could increase cisplatin sensitivity in both OC-3-VGH and OVCAR-3 cells via the mechanism of promoting cisplatin-related apoptosis. CONCLUSIONS: When compared to weak PR-B, ovarian HGSC patients with a strong PR-B expression had a better chance of platinum sensitivity and survival, and this finding was compatible with our experimental results. Progesterone seemed to be a platinum sensitizer, but the value of adding progesterone in the treatment of ovarian HGSC should be further investigated.
ABSTRACT
BACKGROUND: Sinonasal renal cell-like adenocarcinoma is rare and exhibits unique pathological and clinical manifestations. Correct diagnosis and treatment of this newly described entity are challenging for both clinicians and pathologists. METHODS: We report a female patient with sinonasal renal cell-like adenocarcinoma who initially presented with right intermittent epistaxis. RESULTS: A 26-year-old woman presented with a 1-year history of right intermittent epistaxis and hyposmia. Nasal endoscopy revealed a reddish tumor in the right nasal cavity. An MRI revealed a hyperintense tumor arising from the right olfactory cleft accompanied by prominent feeding vessels originating from the anterior ethmoid artery (AEA). We performed a bicoronal incision with ligation of the AEA followed by endoscopic resection of the skull base tumor. The patient is currently free of recurrence. CONCLUSION: This is the first study to review the clinical features of sinonasal renal cell-like adenocarcinoma. We recommend surgical resection as the mainstay of treatment.
Subject(s)
Adenocarcinoma/diagnosis , Carcinoma, Renal Cell/diagnosis , Paranasal Sinus Neoplasms/diagnosis , Adenocarcinoma/surgery , Adult , Diagnosis, Differential , Female , Humans , Paranasal Sinus Neoplasms/surgerySubject(s)
Carcinoma, Skin Appendage , Skin Neoplasms , Sweat Gland Neoplasms , Carcinoma, Skin Appendage/pathology , Demography , Humans , Mucins , Skin Neoplasms/diagnosis , Skin Neoplasms/epidemiology , Skin Neoplasms/pathology , Sweat Gland Neoplasms/diagnosis , Sweat Gland Neoplasms/epidemiology , Sweat Gland Neoplasms/pathology , Sweat Glands/pathologyABSTRACT
To explore the implications of lipid catabolism-associated genes in gastrointestinal stromal tumors, we reappraised transcriptomic and genomic datasets and identified copy-gained and differentially upregulated PLCB4 gene associated with tumor progression. On full sections, PLCB4 mRNA abundance and PLCß4 immunoexpression were validated in 70 cases. On tissue microarrays, PLCB4 gene copies and PLCß4 immunoexpression were both informative in 350 cases with KIT/PDGFRA/BRAF genotypes noted in 213. In GIST48 cell line, we stably silenced PLCB4 and YAP1 to characterize their functional effects and regulatory link. Compared with normal tissue, PLCB4 mRNA abundance significantly increased across tumors of various risk levels (p<0.001), and was strongly correlated with immunoexpression level (p<0.001, r=0.468). Including polysomy (12.6%) and amplification (17.4%), PLCB4 copy gain was detected in 105 (30%) cases and significantly more frequent (p<0.001) in cases exhibiting higher PLCß4 immunoexpression (82/175). Copy gain and protein overexpression were modestly associated with unfavorable genotypes (both p<0.05), strongly associated with increased size, mitosis, and risk levels defined by both the NIH and NCCN schemes (all p<0.001), and univariately predictive of shorter disease-free survival (both p<0.0001). In PLCß4-overexpressing cases, PLCB4 copy gain still predicted worse prognosis (p<0.0001). In a multivariate comparison, both overexpression (p=0.007, hazard ratio: 2.454) and copy gain (p=0.031, hazard ratio: 1.892) exhibited independent impact. In vitro, YAP1 increased PLCB4 mRNA and protein expression, and both molecules significantly promoted cell proliferation. Being driven by copy gain or YAP1, PLCß4 is a novel overexpressed enzyme regulating lipid catabolism that promotes cell proliferation and independently confers a worse prognosis.
Subject(s)
Biomarkers, Tumor/genetics , DNA Copy Number Variations/genetics , Gastrointestinal Neoplasms/genetics , Gastrointestinal Stromal Tumors/genetics , Phospholipase C beta/genetics , Adaptor Proteins, Signal Transducing/genetics , Aged , Apoptosis , Case-Control Studies , Cell Proliferation , Cohort Studies , Female , Follow-Up Studies , Gastrointestinal Neoplasms/pathology , Gastrointestinal Stromal Tumors/pathology , Humans , Male , Middle Aged , Mutation/genetics , Neoplasm Staging , Phosphoproteins/genetics , Prognosis , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins c-kit/genetics , Receptor, Platelet-Derived Growth Factor alpha/genetics , Survival Rate , Transcription Factors , Tumor Cells, Cultured , YAP-Signaling ProteinsABSTRACT
NAB2-STAT6 gene fusion drives STAT6 nuclear expression and is the pathognomonic hallmark of solitary fibrous tumors (SFTs). However, no study has systematically analyzed the clinicopathological features, STAT6 immunoexpression status, or the fusion variants of NAB2-STAT6 in intrathoracic SFTs. Fifty-two intrathoracic SFTs were retrieved to appraise histopathology, assess STAT6 immunoexpression, and determine NAB2-STAT6 fusion variants by RT-PCR. Location-relevant histologic mimics served as controls. Thirty-one pleura-based, 12 mediastinal/pericardial, and nine intrapulmonary lesions were histologically categorized into eight malignant, eight atypical, and 36 conventional or cellular SFTs, including two fat-forming and two giant cell angiofibroma-like SFTs. STAT6 distinctively decorated the tumoral nuclei in 51 (98%) SFTs. However, no nuclear staining was observed in the histological mimics. NAB2-STAT6 fusion was detected in 34 SFTs. Twenty-nine (85.3%) exhibited the major NAB2ex4-STAT6ex2/3 variant and 5 (14.7%) the minor NAB2ex6-STAT6ex16/17. NAB2ex4-STAT6ex2 was significantly associated with older age (P = 0.01) and pleuropulmonary tumors (P = 0.025). After a median follow-up of 33.9 (range, 0.3-174.6) months, adverse outcomes occurred in one atypical and five malignant SFTs, including two local relapses, one intrapulmonary metastasis, and three extrathoracic metastases. Inferior disease-free survival was univariately associated with atypical/malignant histology (P = 0.001) and a mitosis >4/10 HPFs (P = 0.0012) but was unrelated to fusion variants. In conclusion, the majority of intrathoracic SFTs exhibited STAT6 nuclear staining, and NAB2ex4-STAT6ex2/3 was the predominant fusion type. However, clinical aggressiveness is associated with atypical/malignant histology primarily contributed by increased mitosis but was unrelated to the NAB2-STAT6 fusion variants.
Subject(s)
Oncogene Proteins, Fusion/genetics , Repressor Proteins/genetics , STAT6 Transcription Factor/genetics , Solitary Fibrous Tumors/diagnosis , Solitary Fibrous Tumors/genetics , Thoracic Neoplasms/diagnosis , Thoracic Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor , Exons , Female , Genetic Variation , Humans , Immunohistochemistry , Male , Middle Aged , Oncogene Proteins, Fusion/metabolism , Prognosis , Repressor Proteins/metabolism , Retrospective Studies , STAT6 Transcription Factor/metabolism , Sequence Analysis, DNA , Solitary Fibrous Tumors/mortality , Thoracic Neoplasms/mortalityABSTRACT
The role of deregulated cellular metabolism, particularly lipid metabolism, in gastrointestinal stromal tumors (GISTs) remains unclear. Through data mining of published transcriptomes, we examined lipid metabolism-regulating drivers differentially upregulated in high-risk cases and identified monoglyceride lipase (MGLL) as the top-ranking candidate involved in GIST progression. MGLL expression status was examined in three GIST cell lines and two independent sets of primary localized GISTs. MGLL mRNA abundance and immunoexpression was determined in 70 cases through the QuantiGene assay and H-scoring on whole sections, respectively. H-scoring was extended to another cohort for evaluating MGLL immunoexpression on tissue microarrays, yielding 350 informative cases, with KIT/PDGFRA mutation genotypes noted in 213 of them. Both imatinib-sensitive (GIST882) and -resistant (GIST48 and GIST430) cell lines exhibited increased MGLL expression. MGLL mRNA levels significantly increased from adjacent normal tissue to the non-high-risk group (p = 0.030) and from the non-high-risk group to high-risk GISTs (p = 0.012), and were associated with immunoexpression levels (p < 0.001, r = 0.536). MGLL overexpression was associated with the nongastric location (p = 0.022) and increased size (p = 0.017), and was strongly related to mitosis and risk levels defined by NIH and NCCN criteria (all p ≤ 0.001). Univariately, MGLL overexpression was strongly predictive of poorer disease-free and overall survival (both p < 0.001), which remained prognostically independent for both endpoints, along with higher risk levels. Conclusively, MGLL is a lipid metabolic enzyme causatively implicated in GIST progression given its association with unfavorable clincopathological factors and independent negative prognostic effects.