Pharmacological blockage of transforming growth factor-ß signalling by a Traf2- and Nck-interacting kinase inhibitor, NCB-0846.

BACKGROUND: Metastasis is the primary cause of death in cancer patients, and its management is still a major challenge. Epithelial to mesenchymal transition (EMT) has been implicated in the process of cancer metastasis, and its pharmacological interference holds therapeutic promise. METHODS: Traf2- and Nck-interacting kinase (TNIK) functions as a transcriptional coregulator of Wnt target genes. Given the convergence of Wnt and transforming growth factor-ß (TGFß) signalling, we examined the effects of a small-molecule TNIK inhibitor (named NCB-0846) on the TGFß1-induced EMT of lung cancer cells. RESULTS: NCB-0846 inhibited the TGFß1-induced EMT of A549 cells. This inhibition was associated with inhibition of Sma- and Mad-Related Protein-2/3 (SMAD2/3) phosphorylation and nuclear translocation. NCB-0846 abolished the lung metastasis of TGFß1-treated A549 cells injected into the tail veins of immunodeficient mice. The inhibition of EMT was mediated by suppression of the TGFß receptor type-I (TGFBR1) gene, at least partly through the induction of microRNAs targeting the TGFBR1 transcript [miR-320 (a, b and d) and miR-186]. CONCLUSIONS: NCB-0846 pharmacologically blocks the TGFß/SMAD signalling and EMT induction of lung cancer cells by transcriptionally downregulating TGFBRI expression, representing a potentially promising approach for prevention of metastasis in lung cancer patients.

Long Non-Coding RNA CRNDE Is Involved in Resistance to EGFR Tyrosine Kinase Inhibitor in EGFR-Mutant Lung Cancer via eIF4A3/MUC1/EGFR Signaling.

(1) Background: Acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) is an intractable problem for many clinical oncologists. The mechanisms of resistance to EGFR-TKIs are complex. Long non-coding RNAs (lncRNAs) may play an important role in cancer development and metastasis. However, the biological process between lncRNAs and drug resistance to EGFR-mutated lung cancer remains largely unknown. (2) Methods: Osimertinib- and afatinib-resistant EGFR-mutated lung cancer cells were established using a stepwise method. A microarray analysis of non-coding and coding RNAs was performed using parental and resistant EGFR-mutant non-small cell lung cancer (NSCLC) cells and evaluated by bioinformatics analysis through medical-industrial collaboration. (3) Results: Colorectal neoplasia differentially expressed (CRNDE) and DiGeorge syndrome critical region gene 5 (DGCR5) lncRNAs were highly expressed in EGFR-TKI-resistant cells by microarray analysis. RNA-protein binding analysis revealed eukaryotic translation initiation factor 4A3 (eIF4A3) bound in an overlapping manner to CRNDE and DGCR5. The CRNDE downregulates the expression of eIF4A3, mucin 1 (MUC1), and phospho-EGFR. Inhibition of CRNDE activated the eIF4A3/MUC1/EGFR signaling pathway and apoptotic activity, and restored sensitivity to EGFR-TKIs. (4) Conclusions: The results showed that CRNDE is associated with the development of resistance to EGFR-TKIs. CRNDE may be a novel therapeutic target to conquer EGFR-mutant NSCLC.

Prognostic impact of ACTN4 gene copy number alteration in hormone receptor-positive, HER2-negative, node-negative invasive breast carcinoma.

BACKGROUND: Most patients with hormone receptor (HR)-positive, human epidermal growth factor receptor type 2 (HER2)-negative breast cancer can be cured by surgery and endocrine therapy, but a significant proportion suffer recurrences. Actinin-4 is associated with cancer invasion and metastasis, and its genetic alteration may be used for breast cancer prognostication. METHODS: The copy number of the actinin-4 (ACTN4) gene was determined by fluorescence in situ hybridisation (FISH) in two independent cohorts totalling 597 patients (336 from Japan and 261 from the USA) with HR-positive, HER2-negative, node-negative breast cancer. RESULTS: In the Japanese cohort, multivariate analysis revealed that a copy number increase (CNI) of ACTN4 was an independent factor associated with high risks of recurrence (P = 0.01; hazard ratio (HR), 2.95) and breast cancer death (P = 0.014; HR, 4.27). The prognostic significance of ACTN4 CNI was validated in the US cohort, where it was the sole prognostic factor significantly associated with high risks of recurrence (P = 0.04; HR, 2.73) and death (P = 0.016; HR, 4.01). CONCLUSIONS: Copy number analysis of a single gene, ACTN4, can identify early-stage luminal breast cancer patients with a distinct outcome. Such high-risk patients may benefit from adjuvant chemotherapy.

Interstitial lung disease associated with nanoparticle albumin-bound paclitaxel treatment in patients with lung cancer.

BACKGROUND: Nanoparticle albumin-bound paclitaxel is indicated for the treatment of patients with lung cancer. It can induce interstitial lung disease, but the incidence of nanoparticle albumin-bound paclitaxel-associated interstitial lung disease in clinical practice has not been determined. We investigated the incidence of interstitial lung disease in patients with lung cancer who had received nanoparticle albumin-bound paclitaxel therapy at our institution. METHODS: We reviewed clinical data for patients with advanced lung cancer who received nanoparticle albumin-bound paclitaxel with or without carboplatin or bevacizumab therapy at the Nippon Medical School Main Hospital between April 2013 and September 2017. Interstitial lung disease was diagnosed based on clinical symptoms, radiographic findings and exclusion of other diseases. RESULTS: A total of 110 advanced lung cancer patients received nanoparticle albumin-bound paclitaxel, and nine of them (8.2%) developed interstitial lung disease. Of those who developed interstitial lung disease, eight were treated with corticosteroids and three received cyclophosphamide pulse therapy. High-resolution computed tomography images demonstrated diffuse alveolar damage pattern pneumonitis in seven patients and organized pneumonia pattern pneumonitis in two patients. Six of the patients with diffuse alveolar damage pattern pneumonitis died from respiratory failure. The two patients with organized pneumonia pattern pneumonitis recovered. The incidence of interstitial lung disease was 19.0% (8/42) among patients with preexisting interstitial pneumonia and 1.5% (1/68) among those without preexisting interstitial pneumonia. Six patients with preexisting interstitial pneumonia met the criteria for acute exacerbation of interstitial pneumonia (14.3%). CONCLUSION: Nanoparticle albumin-bound paclitaxel-associated interstitial lung disease was a severe and potentially fatal adverse event. We found it demonstrated diffuse alveolar damage or organized pneumonia pattern pneumonitis, and preexisting interstitial pneumonia was associated with higher rate of nanoparticle albumin-bound paclitaxel-associated interstitial lung disease.

Weekly paclitaxel in combination with carboplatin for advanced non-small-cell lung cancer complicated by idiopathic interstitial pneumonias: a single-arm phase II study.

BACKGROUND: Idiopathic interstitial pneumonias (IIPs) are associated with increased risk of lung cancer. In Japan, acute exaberation of IIPs induced by anticancer treatment is a critical issue. For this reason, there is limited available evidence regarding the optimal treatment approach for lung cancer patients complicated with IIPs. Our previous prospective pilot study demonstrated the safety and efficacy of weekly paclitaxel in combination with carboplatin for advanced non-small-cell lung cancer (NSCLC) with IIPs. The current study was conducted to confirm the results of the same combination therapy used in a larger patient population. METHODS: Chemotherapy-naïve patients with advanced stage or post-operative recurrent NSCLC patients complicated by IIPs were enrolled. Patients received paclitaxel (100 mg/m2) on days 1, 8, and 15, and carboplatin (AUC 5.0) once every 4 weeks. RESULTS: Thirty-three of 35 enrolled patients were evaluable for analysis and received a median of four treatment cycles (range 1-6). Four patients (12.1%; 95% confidence interval 3.4-28.2%) had acute exacerbation (AEx)-related IIPs to the study treatment. However, no fatalities due to AEx were observed. The overall response was 69.7%. The median progression-free survival, median survival time, and 1-year survival were 6.3 months, 19.8 months, and 55.4%, respectively. CONCLUSIONS: The efficacy of carboplatin plus weekly paclitaxel treatment for advanced NSCLC patients with IIPs was comparable to that of conventional chemotherapy in advanced NSCLC patients without IIPs. Moreover, the primary endpoint was set to the frequency of treatment-related acute exacerbation, and the primary endpoint was met. These results suggest that patients with advanced NSCLC complicated by IIPs may benefit from this combination chemotherapy.

Control of the MYC-eIF4E axis plus mTOR inhibitor treatment in small cell lung cancer.

BACKGROUND: Mammalian target of rapamycin (mTOR) inhibitors have anti-tumor effects against renal cell carcinoma, pancreatic neuroendocrine cancer and breast cancer. In this study, we analyzed the antitumor effects of mTOR inhibitors in small cell lung cancer (SCLC) cells and sought to clarify the mechanism of resistance to mTOR inhibitors. METHODS: We analyzed the antitumor effects of three mTOR inhibitors including everolimus in 7 SCLC cell lines by MTS assay. Gene-chip analysis, receptor tyrosine kinases (RTK) array and Western blotting analysis were performed to identify molecules associated with resistance to everolimus. RESULTS: Only SBC5 cells showed sensitivity to everolimus by MTS assay. We established two everolimus resistant-SBC5 cell lines (SBC5 R1 and SBC5 R10) by continuous exposure to increasing concentrations of everolimus stepwise. SPP1 and MYC were overexpressed in both SBC5 R1 and SBC5 R10 by gene-chip analysis. High expression levels of eukaryotic translation initiation factor 4E (eIF4E) were observed in 5 everolimus-resistant SCLC cells and SBC5 R10 cells by Western blotting. MYC siRNA reduced eIF4E phosphorylation in SBC5 cells, suggesting that MYC directly activates eIF4E by an mTOR-independent bypass pathway. Importantly, after reduction of MYC or eIF4E by siRNAs, the SBC5 parent and two SBC5-resistant cells displayed increased sensitivity to everolimus relative to the siRNA controls. CONCLUSION: These findings suggest that eIF4E has been shown to be an important factor in the resistance to everolimus in SCLC cells. Furthermore, a link between MYC and mTOR-independent eIF4E contribute to the resistance to everolimus in SCLC cells. Control of the MYC-eIF4E axis may be a novel therapeutic strategy for everolimus action in SCLC.

MET FISH-positive status predicts short progression-free survival and overall survival after gefitinib treatment in lung adenocarcinoma with EGFR mutation.

BACKGROUND: Lung adenocarcinoma patients with EGFR gene mutations have shown a dramatic response to gefitinib. However, drug resistance eventually emerges which limits the mean duration of response. With that in view, we examined the correlations between MET gene status as assessed by fluorescence in situ hybridization (FISH) with overall survival (OS) and progression-free survival (PFS) in adenocarcinoma patients with EGFR gene mutations who had received gefitinib therapy. METHODS: We evaluated 35 lung cancer samples with EGFR mutation from adenocarcinoma patients who had received gefitinib. Gene copy numbers (GCNs) and amplification of MET gene before gefitinib therapy was examined by FISH. MET protein expression was also evaluated by immunohistochemistry (IHC). RESULTS: FISH assessment showed that of the 35 adenocarcinoma samples, 10 patients (29%) exhibited high polysomy (5 copies≦mean MET per cell) and 1 patient (3%) exhibited amplification (2≦MET gene (red)/CEP7q (green) per cell). IHC evaluation of MET protein expression could not confirm MET high polysomy status. The Eleven patients with MET FISH positivity had significantly shorter progression-free survival (PFS) and overall survival (OS) than the 24 patients who were MET FISH-negative (PFS: p = 0.001 and OS: p = 0.03). Median PFS and OS with MET FISH-positivity were 7.6 months and 16.8 months, respectively, whereas PFS and OS with MET FISH-negativity were 15.9 months and 33.0 months, respectively. Univariate analysis revealed that MET FISH-positivity was the most significant independent factor associated with a high risk of progression and death (hazard ratio, 3.83 (p = 0.0008) and 2.25 (p = 0.03), respectively). CONCLUSIONS: Using FISH analysis to detect high polysomy and amplification of MET gene may be useful in predicting shortened PFS and OS after Gefitinib treatment in lung adenocarcinoma. The correlation between MET gene status and clinical outcomes for EGFR-TKI should be further evaluated using large scale samples.

A Case of Binocular Metastatic Choroidal Tumor Originating from Pulmonary Adenocarcinoma Successfully Treated with Molecular Target Therapy.

The occurrence of ocular metastasis from lung cancer is uncommon. In our current case, we report on a 64-year-old male patient found to have metastatic lesions in both choroids after being diagnosed with lung adenocarcinoma. As the patient was found to have a mutation in the epidermal growth factor receptor (EGFR), he was treated with the EGFR tyrosine kinase inhibitor (EGFR TKI), afatinib. However, the treatment response suggested the presence of a progressive disease. Thus, due to cancerous meningitis, the patient's treatment was changed from afatinib to erlotinib, in addition to adding bevacizumab. Although the general condition of the patient did not change, improvement was noted for the choroidal metastasis. Moreover, the drug change also resulted in an improvement of the visual power of both eyes. Therefore, the results for this patient suggest that systemic administration of erlotinib and bevacizumab may be an effective treatment that leads to morphological and functional improvement in choroidal metastasis cases.

Serum-derived exosomal miR-125a-3p predicts the response to anti-programmed cell death-1/programmed cell death-ligand 1 monotherapy in patients with non-small cell lung cancer.

BACKGROUND: Versatile biomarkers for immune checkpoint inhibitors (ICI) efficacy in patients with cancer remain to be identified. Liquid biopsy using serum-derived exosomal microRNAs (miRNAs) are widely investigated as diagnostic and therapeutic outcome predictors in patients with cancer. However, exosomal miRNAs linked to the response to ICI in patients with non-small cell lung cancer (NSCLC) remain elusive thus far. METHODS: The value of serum-derived exosomal miRNAs in predicting the effect of anti-programmed cell death-1 (PD-1)/anti-programmed cell death-ligand 1 (PD-L1) monotherapy in 41 patients with advanced NSCLC was assessed. We performed functional analysis of candidate miRNAs using NSCLC cell lines. RESULTS: Exosomal miR-125a-3p was associated with response to treatment with ICI. Exosomal miR-125a-3p was more useful in predicting response to ICI versus tumoral PD-L1 in patients with low PD-L1 expression <50 %). Moreover, high expression of miR-125a-3p was associated with worse progression-free and overall survival. In H1975 and H441 cells, induction of miR-125a-3p regulated PD-L1 expression via suppression of neuregulin 1 (NRG1). CONCLUSIONS: Exosomal miR-125a-3p is a potential predictor of response to anti-PD-1/PD-L1 therapy in advanced NSCLC patients with low PD-L1 expression.

Clinicopathological characteristics of kidney injury in non-small cell lung cancer patients under combination therapy including pembrolizumab.

Combination therapy, consisting of immune checkpoint inhibitors and traditional chemotherapeutic agents, has significantly improved the clinical outcomes of non-small cell lung cancer. Therefore, it will be a promising first-line therapy, whereas, there is a prospect that associated kidney injury may increase during treatment. We presented four patients, diagnosed with advanced non-small cell lung cancer, who received combination therapy, consisting of pembrolizumab, cisplatin, and pemetrexed as first-line treatment. All of them had been referred to nephrologists and had undergone renal biopsy. We observed that three of four patients presented a very rapid time course for acute kidney injury development. Notably, the three patients received only one or two cycles of the combined chemotherapy. In a renal biopsy, one patient showed severe acute tubular injury rather than interstitial nephritis. Another patient presented focal segmental glomerular sclerosis concomitant with tubulointerstitial nephritis. However, it was challenging to distinguish which agent was primarily responsible for kidney injury. Regarding the treatment, all the patients discontinued pembrolizumab and received corticosteroid treatment. We adjusted the dose and duration of corticosteroid according to the pathological results and patient conditions. The current cases provide a further understanding of clinical features and appropriate management in patients treated with combination therapy including pembrolizumab.

A Novel Molecular Target in EGFR-mutant Lung Cancer Treated With the Combination of Osimertinib and Pemetrexed.

BACKGROUND/AIM: Synergistic effects of epidermal growth factor receptor tyrosine kinase inhibitors and chemotherapy have been reported. Here, we evaluated the therapeutic potential of combining osimertinib with pemetrexed and investigated the molecular mechanisms. MATERIALS AND METHODS: We analyzed the antitumor effects of osimertinib± pemetrexed in PC-9 and H1975 cells. Gene expression on exposure to osimertinib±pemetrexed was assessed in these cultured cells. Cell lines resistant to osimertinib±pemetrexed were established to explore mechanisms of resistance. RESULTS: Osimertinib+pemetrexed treatment delayed the emergence of resistance relative to monotherapy in vitro and in vivo. Expression of the anti-apoptotic gene PLK1 was down-regulated in PC-9 and H1975 exposed to osimertinib+ pemetrexed, whereas it was up-regulated in resistant cells. Furthermore, inhibition of PLK1 induced apoptosis and inhibited proliferation of resistant cells. CONCLUSION: Blocking PLK1 contributes to mediating the synergistic anti-proliferative effect of osimertinib+pemetrexed. PLK1 over-expression may be a critical mechanism for acquired resistance to osimertinib+pemetrexed.

Carboplatin plus nanoparticle albumin-bound paclitaxel for the treatment of thymic carcinoma.

Thymic carcinoma is a relatively rare type of malignant tumor. The present retrospective study evaluated the efficacy and safety of carboplatin plus nanoparticle albumin-bound paclitaxel for the treatment of advanced thymic carcinoma. The study included data from 12 patients with advanced thymic carcinoma treated in the Nippon Medical School Hospital (Tokyo, Japan). Response to treatment, patient survival and treatment safety were assessed. The objective response rate was 66.7% (8/12 patients). Disease control was achieved in 11 patients (91.7%). At the median follow-up time of 27.6 months (range, 6.2-75.1 months), the median progression-free survival and median first-line overall survival times were 16.7 months [95% confidence interval (CI), 13.2-37.7] and 14.3 months (95% CI, 4.7-54.6), respectively. There was no occurrence of febrile neutropenia or treatment-related death. The results of the present study showed that carboplatin plus nanoparticle albumin-bound paclitaxel was effective and safe. Therefore, it is a promising chemotherapy regimen for the treatment of advanced thymic carcinoma.

Acute respiratory failure due to Aspergillus niger infection with acute fibrinous and organazing pneumonia: A case report.

A 59-year-old woman complaining of wet cough, hemoptysis, slight fever, anorexia, and malaise was admitted to hospital with suspected lobar pneumonia. She received treatment for myocardial infarction and deep venous thrombosis caused by familial protein C deficiency. Rapid deterioration due to respiratory failure occurred despite intensive care with broad-spectrum antibiotics. At a later date, sputum examination revealed the presence of Aspergillus niger. Based on clinical and autopsy findings, she was diagnosed with acute respiratory failure due to pulmonary aspergillosis with acute fibrinous and organizing pneumonia. This is the first reported case of pulmonary aspergillosis with acute fibrinous and organizing pneumonia complicated by calcium oxalate resulting from Aspergillus niger infection, leading to severe inflammation and tissue injury in the lungs.

A case of acute and severe thrombocytopenia due to readministration of rifampicin.

A 49-year-old-woman was diagnosed with tuberculosis of the left humerus. She had received treatment, including rifampicin, for tuberculosis 17 years previously. Treatment was begun with isoniazid, rifampicin, ethambutol, and pyrazinamide, but these were discontinued because of mild neutropenia and thrombocytopenia 2 weeks posttreatment. Rifampicin and ethambutol were readministered after a 4-day interruption; however, generalized purpura appeared several hours later. By the next day, her platelet count was reduced from 160 × 10(3) to 3 × 10(3)/µl. The patient improved rapidly after platelet transfusion and steroid treatment. Readministration of drugs other than rifampicin did not induce thrombocytopenia; therefore, thrombocytopenia was likely due to rifampicin.

[A case of sarcomatoid carcinoma of the lung successfully treated with carboplatin, paclitaxel and bevacizumab].

A 63-year-old male smoker with left chest pain was admitted for examination of an abnormal chest shadow. A chest computed tomography (CT) scan revealed a tumor in S6 of the left lung, and left pleural effusion. Histological examination by CT-guided needle biopsy revealed a proliferation of spindle-shaped tumor cells with sarcomatous features. Immunohistochemical staining confirmed the tumor cells to be of epidermal origin, indicating a diagnosis of sarcomatoid carcinoma of the lung. No distant metastases were found, and his disease was judged to be clinical stage IV (T3N2M1a). He received 5 courses of systemic chemotherapy consisting of carboplatin, paclitaxel and bevacizumab, and the tumor shrank. Systemic chemotherapy is generally ineffective for sarcomatoid carcinoma of the lung. However, in the present case this chemotherapy was effective with the addition of bevacizumab.

Exosome-derived miR-210 involved in resistance to osimertinib and epithelial-mesenchymal transition in EGFR mutant non-small cell lung cancer cells.

BACKGROUND: Osimertinib is a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) approved for the treatment of patients with EGFR-mutant non-small cell lung cancer (NSCLC). However, the mechanisms of acquired drug resistance to osimertinib have not as yet been clarified. Exosomes and microRNAs (miRNAs) are involved in carcinogenesis and drug resistance in human cancers. METHODS: We used previously established osimertinib-resistant HCC827 (HCC827-OR) and PC-9 (PC-9-OR) cells. We evaluated the profiles of exosomal miRNA associated with resistance to osimertinib in EGFR-mutant NSCLC cells. RESULTS: Epithelial-mesenchymal transition (EMT) phenomenon was observed in HCC827-OR and PC-9-OR cells. Microarray and quantitative reverse transcription-polymerase chain reaction analysis revealed that miR-210-3p was co-upregulated in exosomes isolated from HCC827-OR and PC-9-OR cells compared with those isolated from parental HCC827 and PC-9 cells. HCC827-OR cell-derived exosomes induced EMT changes and resistance to osimertinib in HCC827 cells. Subsequently, the induction of miR-210-3p directly promoted the EMT phenomenon and resistance to osimertinib in HCC827 cells. CONCLUSIONS: Exosomal miR-210-3p may play a crucial role in resistance to osimertinib in the tumor microenvironment of EGFR-mutant NSCLC.

PD-L1 Expression Status Predicting Survival in Pulmonary Pleomorphic Carcinoma.

BACKGROUND/AIM: Pulmonary pleomorphic carcinoma (PPC) is a rare and aggressive tumor that is resistant to treatment. The expression and prognostic value of programmed cell death-ligand 1 (PD-L1) and its association with epithelial-mesenchymal transition (EMT) in PPC remains unclear. PATIENTS AND METHODS: The expression of PD-L1 and EMT markers, such as E-cadherin, vimentin, zinc finger E-box-binding homeobox 1 (ZEB-1), and cellular mesenchymal-epithelial transition (c-Met) was evaluated by immuno - histochemistry in 16 patients with PPC who underwent surgical resection. RESULTS: The expression of PD-L1 varied between carcinomatous and sarcomatous areas. Positive correlations between PD-L1 and vimentin expression in carcinomatous areas (r=0.668, p=0.005) and PD-L1 and ZEB-1 expression in sarcomatous areas (r=0.562, p=0.023) were found. High PD-L1 and ZEB-1 expression in sarcomatous areas predicted poor survival (p=0.045 and p=0.012, respectively). CONCLUSION: PD-L1 expression associated with ZEB1 expression in the sarcomatoid component of patients with PPC may be useful for predicting patient prognosis.

Successful Treatment with Afatinib after Osimertinib-induced Interstitial Lung Disease in a Patient with EGFR-mutant Non-small-cell Lung Cancer.

Osimertinib is the standard treatment for epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer. However, drug-induced interstitial lung disease (ILD) is recognized as a serious adverse event associated with EGFR-tyrosine kinase inhibitors (TKIs). We herein report a 78-year-old woman with stage IV lung adenocarcinoma harboring an EGFR L858R mutation on exon 21 who received rechallenge treatment with afatinib after osimertinib-induced ILD with an organizing pneumonia pattern. This is the first report of successful rechallenge with afatinib after osimertinib-induced ILD. Treatment with other EGFR-TKIs after osimertinib-induced ILD may be an option for subsequent therapy.

Direct conversion of osteosarcoma to adipocytes by targeting TNIK.

Osteosarcoma (OS) is an aggressive mesenchymal tumor for which no molecularly targeted therapies are available. We have previously identified TRAF2- and NCK-interacting protein kinase (TNIK) as an essential factor for the transactivation of Wnt signal target genes and shown that its inhibition leads to eradication of colorectal cancer stem cells. The involvement of Wnt signaling in the pathogenesis of OS has been implicated. The aim of the present study was to examine the potential of TNIK as a therapeutic target in OS. RNA interference or pharmacological inhibition of TNIK suppressed the proliferation of OS cells. Transcriptome analysis suggested that a small-molecule inhibitor of TNIK upregulated the expression of genes involved in OS cell metabolism and downregulated transcription factors essential for maintaining the stem cell phenotype. Metabolome analysis revealed that this TNIK inhibitor redirected the metabolic network from carbon flux toward lipid accumulation in OS cells. Using in vitro and in vivo OS models, we confirmed that TNIK inhibition abrogated the OS stem cell phenotype, simultaneously driving conversion of OS cells to adipocyte-like cells through induction of PPARγ. In relation to potential therapeutic targeting in clinical practice, TNIK was confirmed to be in an active state in OS cell lines and clinical specimens. From these findings, we conclude that TNIK is applicable as a potential target for treatment of OS, affecting cell fate determination.