Lansoprazole (LPZ) reverses multidrug resistance (MDR) in cancer through impeding ATP-binding cassette (ABC) transporter-mediated chemotherapeutic drug efflux and lysosomal sequestration.

AIMS: Lansoprazole is one of the many proton pump inhibitors (PPIs) that acts more strongly with ABCB1 and ABCG2. The present study is to investigate the potential of lansoprazole on reversal of ABCB1/G2-mediated MDR in cancer, in vitro and in vivo. METHODS: Reversal studies and combination evaluation were conducted to determine the synergistic anti-MDR effects on lansoprazole. Lysosomal staining was used to determination of lansoprazole on ABCB1-mediated lysosomal sequestration. Substrate accumulation and efflux assays, ATPase activity, and molecular docking were conducted to evaluate lansoprazole on ABCB1/G2 functions. Western blot and immunofluorescence were used to detect lansoprazole on ABCB1/G2 expression and subcellular localization. MDR nude mice models were established to evaluate the effects of lansoprazole on MDR in vivo. RESULTS: Lansoprazole attenuated ABCB1/G2-mediated MDR and exhibited synergistic effects with substrate drugs in MDR cells. In vivo experiments demonstrated that lansoprazole attenuated ABCB1/G2-mediated MDR and exhibited synergistic effects that augmented the sensitivity of substrate anticancer drugs in ABCB1/G2-mediated settings without obvious toxicity. Lansoprazole impeded lysosomal sequestration mediated by ABCB1, leading to a substantial increase in intracellular accumulation of substrate drugs. The effects of lansoprazole were not attributable to downregulation or alterations in subcellular localization of ABCB1/G2. Lansoprazole promoted the ATPase activity of ABCB1/G2 and competitively bound to the substrate-binding region of ABCB1/G2. CONCLUSIONS: These findings present novel therapeutic avenues whereby the combination of lansoprazole and chemotherapeutic agents mitigates MDR mediated by ABCB1/G2 overexpression.

Formyl phloroglucinol meroterpenoids from the leaves of Eucalyptus globulus subsp. maidenii and their ATP-citrate lyase inhibitory activities.

Three new formyl phloroglucinol meroterpenoids, eumaidials A-C (1-3), were isolated from the leaves of Eucalyptus globulus subsp. maidenii, along with ten known analogues (4-13). Their chemical structures were determined by various spectral data and electronic circular dichroism calculations. Eumaidial A (1) is the first ß-caryophyllene-based formyl phloroglucinol meroterpenoids from the genus Eucalyptus. Compounds 1-4 and 10 exhibited ATP-citrate lyase inhibitory activities, and compounds 2 and 3 suppressed the hepatocyte lipogenesis.

CD44s and CD44v8-10 isoforms confer acquired resistance to osimertinib by activating the ErbB3/STAT3 signaling pathway.

AIMS: Although epidermal growth factor receptor (EGFR)-mutant lung cancers respond well to osimertinib, acquired resistance to osimertinib eventually develops through EGFR-dependent and EGFR-independent resistance mechanisms. CD44 splicing variants are widely expressed in lung cancer tissues. However, it remains unclear whether specific splicing variants are involved in acquired resistance to osimertinib. MAIN METHODS: The real-time PCR was performed to measure the expression levels of total CD44 and specific CD44 splicing variants (CD44s or CD44v). Gene knockdown and restoration were performed to investigate the effects of CD44 splicing variants on osimertinib sensitivity. Activation of the signaling pathway was evaluated using receptor-tyrosine-kinase phosphorylation membrane arrays, co-immunoprecipitation, and western blotting. KEY FINDINGS: Clinical analysis demonstrated that the expression level of total CD44 increased in primary cancer cells from lung adenocarcinomas patients after the development of acquired resistance to osimertinib. Furthermore, osimertinib-resistant cells showed elevated levels of either the CD44s variant or CD44v variants. Manipulations of CD44s or CD44v8-10 were performed to investigate their effects on treatment sensitivity to osimertinib. Knockdown of CD44 increased osimertinib-induced cell death in osimertinib-resistant cells. However, restoration of CD44s or CD44v8-10 in CD44-knockdown H1975/AZD-sgCD44 cells induced osimertinib resistance. Mechanically, we showed that ErbB3 interacted with CD44 and was transactivated by CD44, that consequently triggered activation of the ErbB3/STAT3 signaling pathway and led to CD44s- or CD44v8-10-mediated osimertinib resistance. SIGNIFICANCE: CD44 is a co-receptor for ErbB3 and triggers activation of the ErbB3 signaling axis, leading to acquired resistance to osimertinib. CD44/ErbB3 signaling may represent a therapeutic target for overcoming osimertinib resistance.

miR-204 suppresses cancer stemness and enhances osimertinib sensitivity in non-small cell lung cancer by targeting CD44.

Osimertinib is an effective treatment option for patients with advanced non-small cell lung cancer (NSCLC) with EGFR activation or T790M resistance mutations; however, acquired resistance to osimertinib can still develop. This study explored novel miRNA-mRNA regulatory mechanisms that contribute to osimertinib resistance in lung cancer. We found that miR-204 expression in osimertinib-resistant lung cancer cells was markedly reduced compared to that in osimertinib-sensitive parental cells. miR-204 expression levels in cancer cells isolated from treatment-naive pleural effusions were significantly higher than those in cells with acquired resistance to osimertinib. miR-204 enhanced the sensitivity of lung cancer cells to osimertinib and suppressed spheroid formation, migration, and invasion of lung cancer cells. Increased miR-204 expression in osimertinib-resistant cells reversed resistance to osimertinib and enhanced osimertinib-induced apoptosis by upregulating BIM expression levels and activating caspases. Restoration of CD44 (the direct downstream target gene of miR-204) expression reversed the effects of miR-204 on osimertinib sensitivity, recovered cancer stem cell and mesenchymal markers, and suppressed E-cadherin expression. The study demonstrates that miR-204 reduced cancer stemness and epithelial-to-mesenchymal transition, thus overcoming osimertinib resistance in lung cancer by inhibiting the CD44 signaling pathway.

LncRNA SLCO4A1-AS1 suppresses lung cancer progression by sequestering the TOX4-NTSR1 signaling axis.

BACKGROUND: Metastasis is a multistep process involving the migration and invasion of cancer cells and is a hallmark of cancer malignancy. Long non-coding RNAs (lncRNAs) play critical roles in the regulation of metastasis. This study aims to elucidate the role of the lncRNA solute carrier organic anion transporter family member 4A1-antisense 1 (SLCO4A1-AS1) in metastasis and its underlying regulatory mechanisms. METHODS: A comprehensive analysis of the Gene Expression Omnibus (GEO) database were used to identify metastasis-associated lncRNAs. Transwell migration and invasion assays, and a tail vein-injection mouse model were used to assess the migration and invasion of cancer cells in vitro and in vivo, respectively. High-throughput screening methods, including MASS Spectrometry and RNA sequencing (RNA-seq), were used to identify the downstream targets of SLCO4A1-AS1. Reverse transcription quantitative polymerase chain reaction (RT-qPCR), western blotting, RNA pull-down, RNA immunoprecipitation (RIP), fluorescence in situ hybridization (FISH), and chromatin immunoprecipitation (ChIp) assays were conducted to identify and validate the underlying regulatory mechanisms of SLCO4A1-AS1. RESULTS: SLCO4A1-AS1 reduced cancer cell migration and invasion by disrupting cytoskeleton filaments, and was associated with longer overall survival in patients with lung adenocarcinoma. SLCO4A1-AS1 directly interacted with the DNA-binding protein, TOX High Mobility Group Box Family Member 4 (TOX4), to inhibit TOX4-induced migration and invasion. Furthermore, RNA-seq revealed that neurotensin receptor 1 (NTSR1) is a novel and convergent downstream target of SLCO4A1-AS1 and TOX4. Mechanistically, SLCO4A1-AS1 functions as a decoy of TOX4 by interrupting its interaction with the NTSR1 promoter and preventing NTSR1 transcription. Functionally, NTSR1 promotes cancer cell migration and invasion through cytoskeletal remodeling, and knockdown of NTSR1 significantly inhibits TOX4-induced migration and invasion. CONCLUSION: These findings demonstrated that SLCO4A1-AS1 antagonizes TOX4/NTSR1 signaling, underscoring its pivotal role in lung cancer cell migration and invasion. These findings hold promise for the development of novel therapeutic strategies targeting the SLCO4A1-AS1/TOX4/NTSR1 axis as a potential avenue for effective therapeutic intervention in lung cancer.

MiR-503 pleiotropically regulates epithelial-mesenchymal transition and targets PTK7 to control lung cancer metastasis.

OBJECTIVE: In lung cancer patients, most deaths are caused by the distant dissemination of cancer cells. Epithelial-mesenchymal transition (EMT) and collective cell migration are distinct and important mechanisms involved in cancer invasion and metastasis. Additionally, microRNA dysregulation contributes significantly to cancer progression. In this study, we aimed to explore the function of miR-503 in cancer metastasis. METHODS: Molecular manipulations (silencing or overexpression) were performed to investigate the biological functions of miR-503 including migration and invasion. Reorganization of cytoskeleton was assessed using immunofluorescence and the relationship between miR-503 and downstream protein tyrosine kinase 7 (PTK7) was assessed using quantitative real-time PCR, immunoblotting, and reporter assays. The tail vein metastatic animal experiments were performed. RESULTS: Herein, we demonstrated that the downregulation of miR-503 confers an invasive phenotype in lung cancer cells and provided in vivo evidence that miR-503 significantly inhibits metastasis. We found that miR-503 inversely regulates EMT, identified PTK7 as a novel miR-503 target, and showed the functional effects of miR-503 on cell migration and invasion were restored upon reconstitution of PTK7 expression. As PTK7 is a Wnt/planar cell polarity protein crucial for collective cell movement, these results implicated miR-503 in both EMT and collective migration. However, the expression of PTK7 did not influence EMT induction, suggesting that miR-503 regulates EMT through mechanisms other than PTK7 inhibition. Furthermore, we discovered that PTK7 mechanistically activates focal adhesion kinase (FAK) and paxillin, thereby controlling the reorganization of the cortical actin cytoskeleton. CONCLUSION: Collectively, miR-503 is capable of governing EMT and PTK7/FAK signaling independently to control the invasion and dissemination of lung cancer cells, indicating that miR-503 represents a pleiotropic regulator of cancer metastasis and hence a potential therapeutic target for lung cancer.

Panscleritis After Blunt Ocular Trauma in A Child with Epididymitis.

We reported an 8-year-old boy with panscleritis in left eye and right epididymitis after falling on the ground. Etiologic diagnosis played a key role in this case. Systemic examinations ruled out systemic autoimmune diseases, tumors, and infections as the cause of scleritis and suggested that the disease was caused by a local delayed-type hypersensitivity (DTH) induced by ocular trauma and was non-infectious. Still, the right epididymitis was infectious. Both conditions were treated successfully using steroids and antibiotics, respectively. Thus, early etiologic diagnosis and reasonable treatment are crucial to prevent visual loss.

Different treatment efficacies and T790M acquisition of EGFR-TKIs on NSCLC patients with variable Del-19 subtypes of EGFR.

EGFR exon 19 deletion (Del-19) comprises multiple advanced NSCLC subtypes. EGFR-tyrosine kinase inhibitor (TKI) efficacy and T790M acquisition in various Del-19 subtypes is unknown. We prospectively collected tissue samples from patients harboring NSCLC with Del-19 between 2006 and 2020. We evaluated EGFR-TKI treatment effectiveness among the different Del-19 subtypes. We collected 1391 NSCLC samples from 892 patients with Del-19, and the most common subtype was del E746-A750 (67.5%). 741 patients had taken first- or second-generation EGFR-TKIs. There were no significant differences in response rates between patients with different Del-19 subtypes (P = .630). Patients with indel E746 had the longest median PFS (14.6 months), but those with non-LRE deletions had the shortest PFS (8.9 months; P = .002). For OS analysis, patients with indel E746 also had the longest OS (34.1 months), but those with non-LRE deletions had the shortest OS (21.1 months; P = .046). Patients with different Del-19 subtypes showed no significant differences in the T790M acquisition rates (P = .443). Among the 151 patients with acquired T790M who received third-generation EGFR-TKIs, the Del-19 subtype was not associated with different RR and PFS. In vitro cellular viability and activation of the EGFR pathway analysis were consistent with the clinical findings. In conclusion, compared with del E746-A750, indel E746 was associated with longer PFS and OS, but the non-LRE subtype was correlated with shorter survival prognosis. There were no significant differences in the acquired T790M rate and treatment effectiveness of subsequent third-generation EGFR-TKIs between various Del-19 subgroups.

Survival outcomes and prognostic factors of lung cancer patients with the MET exon 14 skipping mutation: A single-center real-world study.

Introduction: The MET exon 14 skipping (METex14) mutation is an important oncogenic driver in lung cancer. We performed a retrospective analysis of clinical data from lung cancer patients with the METex14 mutation to analyze their survival outcomes and associated prognostic factors. Methods: A one-step reverse transcription-polymerase chain reaction to examine the presence of the METex14 mutation was performed using RNA samples from 1374 lung cancer patients with no detected EGFR and ALK mutations. Pathological features and immunohistochemistry (IHC) results for c-MET were analyzed in patients with METex14-positive tumors. Results: METex14 was identified in 69 patients with lung cancer, including 53 adenocarcinoma (ADC) and 16 non-ADC patients. In comparison with patients without the METex14 mutation, lung cancer patients harboring the METex14 mutation were generally elderly individuals, never-smokers, and had poor performance scores. A higher frequency of METex14 mutations was detected in pulmonary sarcomatoid carcinoma (PSC) patients (24.3%, n = 9/37). However, stage IV PSC patients with or without the METex14 mutations showed similarly poor overall survival (OS) (p = 0.429). For all 36 METex14-positive lung ADCs, multivariate analysis showed several poor prognostic factors, including strong c-MET IHC staining (p = 0.006), initial brain metastasis (p = 0.005), and administration of only supportive care (p < 0.001). After excluding seven patients who received only supportive care, we further analyzed 29 stage IV lung ADC patients with METex14 mutations who received anti-cancer treatment. Multivariate analysis showed that pemetrexed treatment (p = 0.003), lung radiotherapy (p = 0.020), initial brain metastasis (p = 0.005), and strong c-MET IHC staining (p = 0.012) were independent prognostic factors for OS in these patients. Conclusions: A higher frequency of METex14 mutations was detected in PSC patients. Stage IV PSC patients with or without the METex14 mutations had similarly poor overall survival. Pemetrexed-based chemotherapy, strong c-MET ICH staining, initial brain metastasis, and lung radiotherapy, may help predict survival outcomes in patients with advanced lung ADCs harboring the METex14 mutation.

Modified Perineal Reconstruction Combined with Anal Sphincter Repair for Obstetric Anal Sphincter Injuries.

Objective: The aim of this study was to investigate the clinical effectiveness of modified perineal reconstruction combined with anal sphincter repair in the treatment of obstetric anal sphincter injuries (OASIS). Methods: Twenty consecutive patients with an OASI who underwent modified perineal reconstruction combined with anal sphincter repair in the Department of Colorectal and Anal Surgery of the First Hospital of Jilin University from October 2015 to September 2017 were retrospectively enrolled in this study. Anal function was evaluated using the Williams grade, the Wexner score, anorectal manometry, and transrectal ultrasound. Results: Differences in both the Williams grade and the Wexner score prior to operation and following surgery indicated that anal function had improved, and these differences were statistically significant (P < 0.05). These indices also showed further improvement six months after surgery as compared with values at one month, and again, these differences were statistically significant (P < 0.05). In addition, anorectal manometry at six months following surgery showed statistically significant differences in the maximum anal resting pressure, maximum anal systolic pressure, and anal defecation pressure as compared with values prior to operation (P < 0.05). Postoperative endorectal ultrasound revealed that the anal sphincter presented with close imbricated overlapping. Conclusion: Modified perineal reconstruction combined with anal sphincter repair in the treatment of female perineal defect is associated with a good clinical outcome, strengthening anal function, and reconstructing the perineum, and is a possible method for clinical treatment.

Inhibitory Effect of Short-Term Palpebral Margin Cleaning with Antibiotic Eye Drops on Ocular Surface Flora before Cataract Extraction: A New Preoperative Antibacterial Method.

Objective To explore the clinical significance of the combined application of palpebral margin cleaning and antibiotic eye drops in inhibiting bacterial growth in the palpebral margin and conjunctival sacs before cataract extraction. Methods In this study, 61 patients (97 eyes) with age-related cataract who underwent phacoemulsification and intraocular lens implantation were selected, and randomly grouped. In the experimental group, the combined application of palpebral margin cleaning with cotton pads and levofloxacin eye drops was given for three days before the surgery. In the control group, levofloxacin eye drops alone were applied for three consecutive days. Bacteria samples from the conjunctival sac and eyelid margins were cultivated and identified before and three days after taking antimicrobial measures, respectively. Results In the experimental group, the positive rates of the two bacteria samples were 100% (50/50) and 40% (20/50) before and 10% (5/50) and 0% (0/50) after the treatment. In the control group, the positive rates of the two bacteria samples were 97.9% (46/47) and 29.8% (14/47) before and 40.4% (19/47) and 10.6% (5/47) after the treatment. The positive rates between the two groups were not significantly different before taking antimicrobial measures (P= 0.485 and 0.395), while they were significantly different after taking antimicrobial measures (P = 0.001 and 0.024). Conclusion Combined application of eyelid and palpebral margin cleaning with cotton pads and antibiotic eye drops before cataract extraction imparted excellent antibacterial effects.

The Prevalence of Ectopic Gestation: A Five-Year Study of 1273 Cases.

OBJECTIVE: This study aims to investigate the prevalence, related risk factors, manifestations, and management of ectopic pregnancy in the first hospital of the Jilin University over a five-year period. METHODS: A retrospective study of ectopic pregnancy was conducted in the First Hospital of the Jilin University between January 1, 2010 and December 31, 2014. The results were analyzed using simple descriptive statistics and reported as frequencies and percentages. RESULTS: The results revealed that out of 16,050 gynecological admissions to the hospital over the five-year period, there were 1273 ectopic pregnancies, with a prevalence rate of 7.93% of all gynecological admissions. The majority of these patients were aged 25-34 y and had a past history of abortion (61%) and uterine cavity surgery (38.6%), and a significant number were nulliparous (549, 43.1%). Bleeding accompanied by abdominal pain were the most common presenting complaints (65.2%). A unilateral salpingectomy was performed for most of these patients. CONCLUSION: Ectopic pregnancy had notable morbidity over the five-year period under study, and a history of abortion and uterine cavity surgery were identified as associated risk factors that limited the future reproductive potential of nulliparous women. Therefore, targeted health education campaigns should be conducted in order to enlighten this group of women and the public at large.

Clinicopathological Features and Survival Outcomes of Primary Pulmonary Invasive Mucinous Adenocarcinoma.

Pulmonary invasive mucinous adenocarcinoma (IMA) has unique histological patterns. This study aimed to comprehensively evaluate the clinicopathological features, prognosis, and survival outcomes of IMAs. We retrospectively identified 77 patients with pulmonary IMA and reviewed their clinical and pathological features. Another 520 patients with non-IMA-type ADC were retrieved for comparison with patients with IMA. A new two-tier grading system (high-grade and low-grade IMAs) modified from the pancreatic intraepithelial neoplasia classification system was used for survival analyses. Compared to patients with non-IMA-type ADC, patients with IMA tended to have never smoked (p = 0.01) and had early-stage IMA at initial diagnosis (p < 0.001). For stage I-II diseases, the five-year overall survival (OS) rates were 76% in IMAs and 50% in non-IMA-type ADCs, and a longer OS was observed in patients with IMA (p = 0.002). KRAS mutations were the most commonly detected driver mutations, which occurred in 12 of the 28 (43%) patients. High-grade IMAs were associated with a shorter recurrence-free survival (RFS) for stage I-IIIA diseases (p = 0.010) than low-grade IMAs but not for OS. In conclusion, patients with stage I and II IMA had better OS than those with non-IMA-type ADC. A new two-tier grading system might be useful for predicting RFS in stage I-IIIA IMAs.

A Substage Increase in The AJCC Classification System Improves Prognostic Prediction in Stage III Gastric Cancer With Insufficient Lymph Nodes Removed.

BACKGROUND: The impact of lymph nodes (LNs) removed on the survivals of patients with stage III gastric cancer, especially on that of those who undergo the adjuvant chemotherapy as a compensation for a possibly insufficient lymphadenectomy, is still unclear. METHODS: Consecutive patients (n = 488) with stage III gastric cancer under R0 curative resection followed by adjuvant chemotherapy were analyzed. The overall survival (OS) was compared between patients with insufficient LNs removed (ILNr, <16 LNs) and sufficient LNs removed (SLNr, ≥16 LNs). Performance of the prediction systems was evaluated using the Likelihood ratio χ2 test, Akaike information criterion (AIC), Harrell's concordance index (C-index), and area under the receiver operating characteristic curves (AUC). RESULTS: The OS of patients were significantly longer in those with SLNr relative to those with ILNr (for stage IIIA, 68.2 vs. 43.2 months, P = 0.042; for stage IIIB, 43.7 vs. 24.9 months, P < 0.001; for stage IIIC, 23.9 vs. 8.3 months, P < 0.001; and for total stage III, 37.7 vs. 21.7 months, P < 0.001). However, the OS were similar between stage IIIA patients with ILNr and stage IIIB patients with SLNr (P = 0.928), between IIIB patients with ILNr and IIIC patients with SLNr (P = 0.962), and IIIC patients with ILNr and stage IV (P = 0.668), respectively. A substage increase in the AJCC classification system, from IIIA to IIIB, from IIIB to IIIC, and from IIIC to IV in patients with ILNr, enhanced the accuracy of prognostic prediction in patients with stage III gastric cancer compared to the current TNM system (Likelihood ratio χ2, 188.6 vs. 184.8; AIC, 4336.4 vs. 4340.6; C-index, 0.695 vs. 0.679, P = 0.002). The ROC curves revealed that the performance of prognostic prediction was better in the new prediction system (AUC = 0.699) compared with the current TNM system (AUC = 0.676). CONCLUSIONS: ILNr (LNs <16) impairs the long-term outcomes of stage III gastric cancer underwent adjuvant chemotherapy. The status of LNs removal adds values to the current TNM system in prognostic prediction of stage III gastric cancer.

miR-146b-5p Enhances the Sensitivity of NSCLC to EGFR Tyrosine Kinase Inhibitors by Regulating the IRAK1/NF-κB Pathway.

Although patients with non-small cell lung cancer harboring activating mutations in the epidermal growth factor receptor (EGFR) show good clinical response to EGFR tyrosine kinase inhibitors (TKIs), patients eventually develop acquired resistance. Previous studies have shown that several microRNAs (miRNAs) are involved in EGFR TKI resistance. Here, we aimed to investigate whether miR-146b-5p sensitizes the EGFR TKI-resistant lung cancer cells. Clinical analysis showed that miR-146b-5p expression in lung cancer cells isolated from pleural effusions of treatment-naive patients was significantly higher than that after acquiring resistance to EGFR TKI treatment. Ectopic expression of miR-146b-5p in EGFR TKI-resistant cells enhanced EGFR TKI-induced apoptosis. The same results were observed in EGFR-dependent and -independent osimertinib-resistant primary cancer cells (PE3479 and PE2988). Mechanically, miR-146b-5p suppressed nuclear factor κB (NF-κB) activity and NF-κB-related IL-6 and IL-8 production by targeting IRAK1. A negative correlation was observed between miR-146b-5p and IRAK1 in clinical specimens. In rescue experiments, restoration of IRAK1 expression reversed the effects of miR-146b-5p on EGFR TKI sensitivity and recovered NF-κB-regulated IL-6 and IL-8 production. In conclusion, miR-146b-5p/IRAK1/NF-κB signaling is important in promoting EGFR TKI resistance, and miR-146b-5p may be a useful tool for overcoming EGFR TKI resistance.

Association of Programmed Death-Ligand 1 Expression with Fusion Variants and Clinical Outcomes in Patients with Anaplastic Lymphoma Kinase-Positive Lung Adenocarcinoma Receiving Crizotinib.

BACKGROUND: Programmed death-ligand 1 (PD-L1) expression is associated with clinical outcomes of epidermal growth factor receptor (EGFR) mutant lung adenocarcinoma (ADC) treated with tyrosine kinase inhibitors (TKIs). However, whether PD-L1 expression plays a role in anaplastic lymphoma kinase (ALK)-positive lung ADC is unknown. We aimed to evaluate the impact of PD-L1 in patients with ALK-positive lung ADC receiving crizotinib. MATERIALS AND METHODS: PD-L1 expression was identified by immunohistochemistry (IHC). Reverse transcriptase-polymerase chain reaction was used for ALK variant detection, and immunofluorescence-based multiplex staining was applied for exploring immune cells in tumor microenvironments. RESULTS: A total of 78 patients with ALK-positive advanced ADC were enrolled in our study, of whom 52 received crizotinib. Compared with EGFR/ALK wild-type tumors, PD-L1 expression was lower in ALK-positive ADC. ALK fusion variants were identified in 32 patients, and those with variant 3 and 5 (short variants) had higher PD-L1 expression than those with other variants. The crizotinib objective response rate (ORR) and progression-free survival (PFS) was better in tumors with negative PD-L1 expression (ORR/PFS in PD-L1 0% vs. 1%-49% vs. 50%-100%: 60.7%/11.8 months vs. 38.5%/6.5 months vs. 36.4%/4.0 months, p = .007/.022). The multivariate Cox proportional hazards model revealed that PD-L1 0% (vs. ≥1%) was an independent factor for longer PFS (adjusted hazard ratio 0.322, 95% confidence interval 0.160-0.650, p = .002). Multiplex IHC in three cases showed a varied extent of immune cell infiltrations in tumors with different PD-L1 expression. CONCLUSION: Positive PD-L1 expression was associated with unfavorable clinical outcomes in patients with ALK-positive lung ADC receiving crizotinib. IMPLICATIONS FOR PRACTICE: Not all lung adenocarcinoma with sensitizing driver mutations experienced durable responses to small-molecule tyrosine kinase inhibitors (TKIs). Similar to the negative impact of programmed death-ligand 1 (PD-L1) in epidermal growth factor receptor mutant tumors treated with TKIs, this study demonstrated that positive PD-L1 expression was also associated with worse response rate and shorter progression-free survival of anaplastic lymphoma kinase (ALK)-positive adenocarcinoma treated with crizotinib. Among different ALK fusion partners, tumors with short variants (V3 and V5) had higher PD-L1 compared with long variants (V1, V2, and V6). Testing PD-L1 before initiating crizotinib for ALK-positive lung cancer could be a simple method to provide important prognostic information.

Complex EGFR mutations with secondary T790M mutation confer shorter osimertinib progression-free survival and overall survival in advanced non-small cell lung cancer.

OBJECTIVES: Osimertinib is active against epidermal growth factor receptor (EGFR) T790M-mutated non-small cell lung cancer (NSCLC). However, its efficacy against complex EGFR mutations with T790M has not been evaluated. MATERIALS AND METHODS: In order to detect complex EGFR mutations, we consecutively sequenced cancer tissues by RNA reverse transcription polymerase chain reaction. Patients with advanced NSCLC with activating EGFR mutation and secondary T790M who received osimertinib were enrolled. Patients' clinicopathologic characteristics, prior treatment details, and osimertinib treatment outcomes were analyzed. RESULTS: Totally, 165 sequenced patients were analyzed. Eleven (7%) of them had complex EGFR mutations with T790M. The osimertinib response rate was 27%. They had a shorter progression-free survival (PFS) (median, 2.9 and 9.7 months, p < 0.001) and overall survival (OS) (median, 17.8 and 31.0 months, p = 0.01) than patients with a single EGFR mutation with T790M. After osimertinib failure, seven patients received rebiopsy with molecular analysis. Four lost the T790M, two transformed to small cell and one acquired C797S. Moreover, taking the median as the demarcation, patients received shorter prior EGFR tyrosine kinase inhibitor (TKI) treatment duration had a shorter osimertinib PFS (median, 7.3 and 13.8 months, p < 0.001) and OS (median, 21.5 and 36.7 months, p = 0.003). Multivariate Cox regression analysis confirmed complex EGFR mutations and prior EGFR TKI treatment duration were independent factors for osimertinib PFS and OS. CONCLUSIONS: Complex EGFR mutations and shorter prior EGFR TKI treatment duration may confer shorter osimertinib PFS and OS in advanced NSCLC with secondary T790M mutation.

MiR-200c-3p suppression is associated with development of acquired resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in EGFR mutant non-small cell lung cancer via a mediating epithelial-to-mesenchymal transition (EMT) process.

BACKGROUND: EGFR-mutant lung cancer inevitably develops resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). OBJECTIVE: To investigate the clinical relevance of microRNAs (miRNAs) in TKI therapy response and resistance. METHODS: We performed a miRNA PCR array analysis and used The Cancer Genome Atlas (TCGA) database to identify potential miRNAs related to EGFR TKIs resistance. We then correlated miRNA expression in 70 surgical and 50 malignant pleural effusion specimens with patient outcomes in those with non-small cell lung carcinoma. Molecular manipulation was performed in EGFR mutant lung cancer cells to assess the effect of miR-200c-3p on cell migratory ability and EGFR-TKI sensitivity. RESULTS: We identified miR-200c-3p and miR-203a-3p as potential EGFR TKI resistance regulators via their modulation of epithelial-to-mesenchymal transition (EMT). MiR-200c-3p and miR-203a-3p were down-regulated in EGFR TKI-resistant cell lines. Progression-free survival (PFS) with EGFR-TKI treatment of patients with high miR-200c-3p expression, but not miR-203a-3p, in the specimens was significantly longer than that of patients with low expression. MiR-200c-3p overexpression inhibited the EMT process in EGFR TKI resistance cell lines and promoted cell death. MiR-200c-3p silencing in EGFR TKI sensitive cell lines increased drug resistance. CONCLUSION: MiR-200c-3p plays a role in sensitivity to EGFR TKIs via modulating EMT process.

The Impact of Clinical Factors, ALK Fusion Variants, and BIM Polymorphism on Crizotinib-Treated Advanced EML4-ALK Rearranged Non-small Cell Lung Cancer.

Patients' clinical factors and genetics factors such as anaplastic lymphoma kinase (ALK) fusion variants and BIM (Bcl-2-like 11) polymorphism were reported to be associated with clinical outcome in crizotinib-treated advanced non-small cell lung cancer (NSCLC). However, the results were still controversial. We analyzed outcome of 54 patients with known ALK fusion variants who received crizotinib for advanced NSCLC. Thirty of them had successful BIM polymorphism analysis and 6 (20%) had a BIM deletion. Multivariate Cox regression analysis found that previous anticancer therapy [adjusted hazard ratio (aHR) 1.35, 95% confidence interval (CI), 1.04-1.76 for each additional line of therapy, p = 0.025] and Eastern Cooperative Oncology Group (ECOG) performance status ≥2 (aHR 8.35, 95% CI, 1.52-45.94, p = 0.015) were independent factors for progression-free survival (PFS). Only ECOG performance status ≥2 (aHR 7.20, 95% CI, 1.27-40.79, p = 0.026) was an independent factor for overall survival (OS). Neither ALK fusion variants nor the presence of a BIM deletion was associated with crizotinib PFS or OS. After adjusting with clinical factors, different ALK variants and BIM polymorphism might not be independent factors for crizotinib PFS or OS in advanced NSCLC with ALK rearrangement.

Acquired resistance to EGFR tyrosine kinase inhibitors is mediated by the reactivation of STC2/JUN/AXL signaling in lung cancer.

Constitutive activation of the epidermal growth factor receptor (EGFR) signaling pathway is implicated in the initiation and progression of lung cancer. EGFR tyrosine kinase inhibitor (TKI)-targeted therapy has become the standard treatment for nonsmall cell lung cancer (NSCLC) patients. However, acquired resistance to these agents remains a major obstacle for managing NSCLC. Here, we investigated a novel strategy to overcome EGFR TKI resistance by targeting the stanniocalcin 2 (STC2)-JUN-AXL pathway. We revealed that STC2 was expressed at significantly higher levels in EGFR TKI-resistant cells. Further, clinical analysis showed that STC2 expression was increased after the development of EGFR TKI resistance and that higher levels were correlated with shorter progression-free survival in EGFR TKI-treated lung cancer patients. Moreover, STC2 overexpression in EGFR TKI-sensitive cells resulted in EGFR TKI resistance. Conversely, genetic silencing of STC2 rendered EGFR TKI-resistant cells more sensitive to EGFR TKIs. Mechanically, STC2 enhanced AXL promoter activity by increasing the phosphorylation of c-Jun, which is an indispensable transcription factor that transactivates AXL. STC2 promoted activation of the JUN-AXL-extracellular signal-regulated kinase (ERK) signaling axis in lung cancer cells. Pharmacological or genetic inhibition of AXL-ERK activity inhibited STC2-mediated EGFR TKI resistance. We also demonstrated that PE2988 cells, a C797S-independent osimertinib-resistant primary cancer cell line from a lung cancer patient, responded to combined AXL inhibitor and osimertinib treatment. In conclusion, our research indicates that STC2 overexpression is important for acquired resistance to EGFR TKIs and that STC2-JUN-AXL-ERK signaling might be a potential therapeutic target to overcome resistance to EGFR TKIs.