Tyrosine Kinase Inhibitor AG1478 Research Articles

Abstract 5145: Association of a ctDNA biomarker of treatment response with clinical outcomes in a real-world pan-cancer cohort treated with tyrosine kinase inhibitors

Abstract Clinical evidence suggests that early changes in circulating tumor DNA tumor fraction (ctDNA TF) is predictive of patient response to immune checkpoint inhibitors, but the extent to which this approach can be used for patients on Tyrosine Kinase Inhibitors (TKIs) is not known. Here, we use xF Monitor to estimate ctDNA TF in patients that received TKIs and show that changes in circulating TF correlate with outcomes in a real-world pan-cancer cohort. Tempus xF Monitor is a ctDNA assay that measures quantitative molecular changes in ctDNA TF by utilizing diverse genomic events, dynamically weighting somatic variant allele frequencies and copy number variants, while using germline information to inform these estimates and providing single nucleotide variant (SNV) results on 105 genes. Molecular responders (MR) were defined as patients with ≥50% reduction in ctDNA TF between baseline and on-treatment time points, consistent with our previously established threshold. Deidentified patient records from the Tempus multimodal database were analyzed if patients had an xF test ≤ 15 weeks prior to the start of their first TKI regimen and an xF test 15 -180 days post-TKI initiation. Patients received TKI agents as classified in the Tempus Medical Ontology, which assigns a unique ID to key clinical concepts, validated and harmonized across industry standard terminologies. The TKI list was further validated using the NCI Metathesaurus (https://ncim.nci.nih.gov/ncimbrowser/) TKI concept (NCI Code C1967). Clinical endpoints were defined from TKI start to the first progression event or death (rwPFS) or death (rwOS), both censored on the last follow-up in event-free patients. Kaplan Meier analysis and Cox proportional hazard models were fitted to compare MR status and survival outcomes on TKI. The evaluable pan-cancer cohort N=69, median age = 61.5 yo, advanced/metastatic disease = 72%, 65% were female, consisted of > 10 cancer diagnoses (35% NSCLC, 26% BC), 41% 1L. In this cohort, 49% of patients received a TKI combination regimen, 21% with CT, 18% with ICI. 68% of patients with NGS testing received matched targeted mutation therapies based on NCCN guidelines. Patients classified as MR based on xF Monitor results had improved survival outcomes with a median rwOS of 951 days (vs 439 days for non-MRs). MR patients had significantly longer rwPFS (HR = 0.383, p = 0.005, CI = 0.12 - 0.75) and rwOS (HR = 0.205, p = 0.004, CI = 0.07 - 0.61) than non-MRs. xF Monitor is a novel tumor naive serial quantitative ctDNA TF algorithm off the Tempus xF assay that has the potential to be used clinically as a monitoring biomarker to stratify patients who are likely to benefit from TKI therapy. xF monitor can be used as a strategy to identify patients at a high risk of progression who could benefit from early switch or intensifying therapy. Results need to be prospectively validated in a larger cohort. Citation Format: Akash Mitra, John Guittar, Regina Schwind, Terri Driessen, Matthew Berginski, Christine Lo, Michelle M. Stein, Jonathan Freaney, Seung Won Hyun, Chithra Sangli, Kate Sasser, Halla Nimeiri, Aadel Chaudhuri. Association of a ctDNA biomarker of treatment response with clinical outcomes in a real-world pan-cancer cohort treated with tyrosine kinase inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5145.

SHP2 Inhibition Overcomes Adaptive and Acquired Resistance to FLT3 TKI to Improve Efficacy Against FLT3/ITD AML

FMS-like tyrosine kinase-3 (FLT3) is a receptor tyrosine kinase (RTK) that is frequently mutated in acute myeloid leukemia (AML), with the internal tandem mutation (FLT3/ITD) conferring a poor prognosis to AML patients. This makes FLT3/ITD AML a validated target for treatment with tyrosine kinase inhibitors (TKI), but their success has been hindered by mechanisms of resistance including rapid signal reprogramming known as adaptive resistance and acquired resistance gained through long-term treatment. Past work from our lab has shown that FLT3/ITD cells undergo adaptive resistance, through the rapid reactivation of ERK signaling within 24 hours of sustained FLT3 inhibition. To improve therapy of FLT3/ITD AML it is important to identify therapeutic targets that overcome this ERK reactivation. Since adaptive ERK reactivation is often due to the relief of negative feedback loops that result in the activation of other RTK, we performed an RTK phospho-array on the FLT3/ITD cell line MV4;11. 48-hour treatment with the FLT3 TKI sorafenib resulted in increased activation of IGF-R, HER3 and AXL. While recent work from our lab found that combining AXL and FLT3 inhibition abrogated the ERK reactivation and exerted greater antileukemic effects, the activation of multiple RTKs suggests that targeting a signaling hub that inhibits multiple RTKs at once will likely prove more efficacious in overcoming this adaptive response. Recent literature has implicated SH2-containing protein tyrosine phosphatase 2 (SHP2) as a therapeutic target in adaptive ERK reactivation in other cancers. SHP2 acts directly downstream of RTKs and is involved in the activation of the ERK pathway. Therefore, we explored whether the addition of an SHP2 inhibitorto FLT3 TKI can overcome the adaptive response and increase treatment efficacy. To explore this possibility, we first treated the FLT3/ITD cell lines Molm14 and MV4;11 as well as FLT3/ITD patient samples with FLT3 TKI alone or in combination with an SHP2 inhibitor for 24 hours. The addition of SHP099 to sorafenib decreased the expected ERK reactivation in a dose-dependent manner. Furthermore, combination treatment with synergized to decrease proliferation and increase apoptosis in the FLT3/ITD cell lines. Impressively, in a long-term assay, treatment with the combination for just 72 hours greatly reduced leukemic cell recovery. To determine whether this combination would improve efficacy in vivo, we engrafted NSG mice with Molm14 cells and treated them for 4 weeks via oral gavage. The combination of SHP099 with gilteritinib group resulted in a statistically significantly lower leukemia burden compared to either treatment alone and the vehicle control. The combination group also had prolonged survival compared to the other groups. In addition to rapid adaptive resistance, there are mechanisms of acquired resistance that render traditional FLT3 TKI treatments ineffective against FLT3/ITD AML cells. We next examined the effects of SHP2 inhibition on FLT3-TKI resistant cells models that were generated by growing and maintaining Molm14 and MV4;11 cells in the presence of FLT3 TKI. The combination of FLT3 TKI and SHP099 resensitized the cells to FLT3 TKI, resulting in decreased ERK phosphorylation, decreased proliferation and increased apoptosis of these FLT3 TKI resistant cells. We also explored the effects of treating the FLT3/ITD mutant cell lines with the combination of SHP099 and several of the cytotoxic chemotherapy agents typically used in the treatment of AML including cytarabine and daunorubicin. While daunorubicin or cytarabine alone had little effect on the level of phosphorylated ERK, the addition of SHP099 decreased ERK activation and the combination synergized to exert greater to decrease proliferation and increase apoptosis. These studies reveal that combining FLT3 TKI treatment with an allosteric SHP2 inhibitor decreases the adaptive ERK reactivation observed in FLT3/ITD cells. The finding that SHP099 synergized with both FLT3 TKI and chemotherapy agents in different FLT3-mutated AML models speaks to the versatile efficacy of SHP2 inhibition in multiple AML models. Taken together, the data suggests that SHP2 inhibition can help overcome both adaptive and acquired resistance in FLT3/ITD AML and is a candidate to try to improve patient outcomes.

EGFR Suppression Inhibits the Sphere Formation of MCF7 Cells Overexpressing EGFR.

The epidermal growth factor receptor (EGFR) is an oncogenic tyrosine kinase that is involved in tumor initiation and progression, making EGFR inhibitors and monoclonal antibodies to this receptor essential for anti-tumor therapy. We have previously shown that EGFR transgene expression in the human breast adenocarcinoma cell line MCF7 (MCF7-EGFR) stimulates the 3D spheroid-like growth. The primary focus of our present work was to investigate whether EGFR inhibition could affect the assembly of spheroids or lead to the destruction of pre-existing spheroids. We compared the effects of anti-EGFR siRNA, the anti-EGFR monoclonal antibody cetuximab, and the tyrosine kinase inhibitor AG1478 on dissociated and spheroid MCF7-EGFR cells. MCF7-EGFR cells were found to have a 2.5-fold higher sensitivity towards the cytotoxic effects of cetuximab and AG1478 compared with the parental MCF7 cell line. The suppression of EGFR mRNA with siRNA was found to reduce the sphere formation, whereas treating the pre-existing spheroids had no such effect. Treatment of dissociated spheroids with cetuximab and AG1478 was also found to inhibit the MCF7-EGFR sphere formation. We suggest that EGFR expression is important, at least, during the spheroid formation stage. The transition of a MCF7wt adherent cell culture to MCF7-EGFR spheroids was accompanied by a considerable increase in N-cadherin adhesion proteins. The level of N-cadherin decreased when MCF7-EGFR cells were treated with siRNA and cetuximab. Thus, we have demonstrated that N-cadherin is involved in the EGFR-dependent formation of MCF7-EGFR spheroids. Accordingly, MCF7-EGFR spheroids can be considered a suitable model for studying aggressive hormone-positive breast tumors.

Integrating Red Blood Cell Features and Hemoglobin Levels in Metastatic Renal Cell Carcinoma Patients Treated with Pazopanib or Cabozantinib: An Easily Exploitable Prognostic Score.

The advent of immune checkpoint inhibitors (ICIs) has revolutionized the metastatic renal cell carcinoma (mRCC) therapeutic landscape. Nevertheless, tyrosine-kinase inhibitors (TKIs) targeting the vascular endothelial growth factor (VEGF) axis still play a key role. The aim of the present study was to explore the prognostic performance of an integrated blood score, based on hemoglobin (Hb) concentration, mean corpuscular volume (MCV), and red cell distribution width (RDW), in mRCC patients treated with anti-VEGF TKIs. The primary endpoint was to correlate Hb, MCV, and RDW with progression-free survival (PFS) and overall survival (OS). Our multicenter retrospective observational study involved mRCC patients treated with pazopanib or cabozantinib from January 2012 to December 2020 in nine Italian centers. Clinical records and laboratory data, including Hb levels, MCV, and RDW, were collected at baseline. Descriptive statistics and univariate and multivariate analyses were performed. We enrolled 301 mRCC patients of which 179 (59%) underwent pazopanib, and 122 (41%) cabozantinib. We considered baseline Hb ≥12 g/dL, MCV >87 fL, and RDW ≤16% as good prognostic factors; hence, developing a multiparametric score capable of delineating 4 different categories. The number of good prognostic factors was associated with significantly longer PFS and OS (p < 0.001 for both). Therefore, we developed a red blood cell-based score by stratifying cases into two groups (2-3 versus 0-1, good factors). The impact on PFS and OS was even more striking (median PFS (mPFS): 16.3 vs 7.9 months; median OS (mOS): 33.7 vs 14.1 months)), regardless of the TKI agent. When challenged with univariate and multivariate analysis, the blood score maintained its high prognostic significance in terms of OS (multivariate analysis HR for OS: 0.53, 95% CI 0.39-0.75; p < 0.001, respectively), while the impact on PFS resulted in borderline significance. Our analyses demonstrate the prognostic role of a multiparametric score based on easily exploitable blood parameters, such as Hb concentration, MCV, and RDW. The red blood cell-based score may underlie the upregulation of the HIF-1α pathway and VEGF axis, thereby identifying a selected population who is likely to benefit from TKI therapy.

Mortality rate and social disparity trends with tyrosine kinase inhibitory availability in chronic myelogenous leukemia: An analysis in the US from 1999 to 2020.

7055 Background: We analyzed CML mortality from 1999 to 2020 in the US in relation to FDA approval of tyrosine kinase inhibitors (TKIs). These agents were introduced in the 2000s, revolutionizing the treatment of CML and providing a paradigm for targeted therapy in oncology. Starting with imatinib in 2001, followed by dasatinib (2006), nilotinib (2007), and bosutinib (2012). TKIs have increased tolerability and efficacy for the treatment of CML as compared to previous treatment modalities. We investigated age-adjusted mortality rates (AAMR) and annual percent change (APC) in this population in relation to TKI approval. Methods: Using the CDC WONDER database, we examined mortality trends from 1999 to 2020 for CML in the US. AAMRs were calculated per 100,000 people and stratified by sex, race/ethnicity, and census region. AAMR groups were listed as pre-TKI era and 1 year post-FDA approval of different TKI agents. We computed the APC trends for the respective stratification with Joinpoint, a regression analysis program. Results: Between 1999 and 2020 there were 35,268 deaths from CML. In 1999, overall AAMR initially was 0.8, which improved to 0.5 by 2020 with a respective APC of -2.5%. In our subgroup analysis there was a consistent and significant decrease in AAMR since the introduction of Imatinib in 2001. With additional TKI releases, AAMR continued to decline in all subgroups. APC for mortality rates was similar between all subgroups [-2.0 to -2.8%] indicating a similar benefit regardless of subgroup. Male AAMR was consistently higher than female AAMR. Black and white patients (0.5, 2020) have a 2.5x higher AAMR (0.2, 2020) compared to Asian patients. Census region did not show a significant difference between each other. Conclusions: Since the FDA approval of imatinib in 2001 and the subsequent release of TKIs there has been a significant impact on reducing AAMR for patients with CML. The decline was seen in sex, race, and census region. The APCs were similar between all subgroups indicating a consistent improvement in survival. Possible etiologies of disparities in AARM for males in comparison to females and for black and white patients in comparison to Asian patients include gender and race-associated gene polymorphisms possibly inducing differences in drug metabolism. Further gender and race specific pharmacokinetic studies would be useful to further elucidate etiology of the disparity and may lead to changes in TKI dosing strategies. [Table: see text]

Safety and efficacy of transarterial chemoembolization combined with tyrosine kinase inhibitors and camrelizumab in the treatment of patients with advanced unresectable hepatocellular carcinoma.

4079 Background: Combined systemic and local therapy is a promising treatment strategy for patients with advanced hepatocellular carcinoma (HCC). Transarterial chemoembolization (TACE), tyrosine kinase inhibitors (TKI) and PD-1 antibodies are all recommended for patients with unresectable HCC (uHCC). This study was aimed to evaluate the efficacy and safety of TACE combined with TKIs and camrelizumab in the treatment of uHCC. Methods: In this multicenter, single-arm phase II trial (ChiCTR2000039508), patients with intermediate-stage uHCC who had a Child-Pugh score ≤ 7 and had not received prior systemic anti-cancer treatment would receive treatment with TACE followed by immunotherapy with camrelizumab 200 mg every 3 weeks plus a TKI agent selected from lenvatinib (12 mg/day for bodyweight ≥60 kg or 8 mg/day for bodyweight &lt;60 kg), sorafenib 400 mg bid or donafenib 200 mg bid until intolerable toxicity or disease progression. During the study treatment, patients assessed as eligible for resection would undergo surgery. The primary endpoint was objective response rate (ORR) per modified RECIST. Secondary endpoints included progression-free survival (PFS), disease control rate (DCR), duration of response (DOR) and overall survival (OS). Results: From September 2020 to November 2021, 87 patients (81 men and 6 women; median age, 56 years) were enrolled. Among them, 43 (49.4%) patients had extrahepatic metastases, and 65 (74.7%) patients had HBV infection. As of September 28, 2022, the median duration of follow-up was 13.6 (0.83-24.9) months. A total of 34 patients (39.1%) died, and the median OS was not reached. The median PFS was 10.5 months (95% CI: 7.8-13.1). The ORR rate was 71.3% (62/87), and the DCR rate was 89.7% (78/87) per mRECIST. According to RECIST version 1.1, the ORR rate was 35.6% (31/87), and the DCR rate was 87.4% (76/87). The ORR and PFS showed consistent benefits in subgroups based on ECOG score, HBV infection, baseline alpha-fetoprotein level, combined TKI, and the number of TACE treatments. Ten patients (11.5%) successfully underwent conversion therapy and all achieved R0 resection. Two patients achieved a complete pathological response (pCR) and four achieved a major pathological response (MPR). The most common AEs were hypoproteinemia (92%), elevated lactate dehydrogenase (80.5%), elevated glutamic oxaloacetic transaminase (79.3%), elevated bilirubin (78.2%), abdominal pain (62.1%), nausea (33.3%), and RCCEP (26.4%). The incidence of grade 3-4 adverse reactions was 67.8%, and no treatment-related deaths occurred. Conclusions: TACE combined with TKI and camrelizumab showed promising clinical benefits. It can effectively control tumor progression and provide opportunities for resection with acceptable safety, which will bring great benefits to uHCC. Clinical trial information: ChiCTR2000039508 .

Clinical efficacy and safety of immune checkpoint inhibitor in combination with regorafenib therapy as second⁃line regimen for patients with unresectable hepatocellular carcinoma.

e16105 Background: Combined systemic and local therapy is a promising treatment strategy for patients with advanced hepatocellular carcinoma (HCC). Transarterial chemoembolization (TACE), tyrosine kinase inhibitors (TKI) and PD-1 antibodies are all recommended for patients with unresectable HCC (uHCC). This study was aimed to evaluate the efficacy and safety of TACE combined with TKIs and camrelizumab in the treatment of uHCC. Methods: In this multicenter, single-arm phase II trial (ChiCTR2000039508), patients with intermediate-stage uHCC who had a Child-Pugh score ≤ 7 and had not received prior systemic anti-cancer treatment would receive treatment with TACE followed by immunotherapy with camrelizumab 200 mg every 3 weeks plus a TKI agent selected from lenvatinib (12 mg/day for bodyweight ≥60 kg or 8 mg/day for bodyweight &lt;60 kg), sorafenib 400 mg bid or donafenib 200 mg bid until intolerable toxicity or disease progression. During the study treatment, patients assessed as eligible for resection would undergo surgery. The primary endpoint was objective response rate (ORR) per modified RECIST. Secondary endpoints included progression-free survival (PFS), disease control rate (DCR), duration of response (DOR) and overall survival (OS). Results: From September 2020 to November 2021, 87 patients (81 men and 6 women; median age, 56 years) were enrolled. Among them, 43 (49.4%) patients had extrahepatic metastases, and 65 (74.7%) patients had HBV infection. As of September 28, 2022, the median duration of follow-up was 13.6 (0.83-24.9) months. A total of 34 patients (39.1%) died, and the median OS was not reached. The median PFS was 10.5 months (95% CI: 7.8-13.1). The ORR rate was 71.3% (62/87), and the DCR rate was 89.7% (78/87) per mRECIST. According to RECIST version 1.1, the ORR rate was 35.6% (31/87), and the DCR rate was 87.4% (76/87). The ORR and PFS showed consistent benefits in subgroups based on ECOG score, HBV infection, baseline alpha-fetoprotein level, combined TKI, and the number of TACE treatments. Ten patients (11.5%) successfully underwent conversion therapy and all achieved R0 resection. Two patients achieved a complete pathological response (pCR) and four achieved a major pathological response (MPR). The most common AEs were hypoproteinemia (92%), elevated lactate dehydrogenase (80.5%), elevated glutamic oxaloacetic transaminase (79.3%), elevated bilirubin (78.2%), abdominal pain (62.1%), nausea (33.3%), and RCCEP (26.4%). The incidence of grade 3-4 adverse reactions was 67.8%, and no treatment-related deaths occurred. Conclusions: TACE combined with TKI and camrelizumab showed promising clinical benefits. It can effectively control tumor progression and provide opportunities for resection with acceptable safety, which will bring great benefits to uHCC.

Tyrosine kinase inhibitors and human epidermal growth factor receptor-2 positive breast cancer.

The body of evidence investigating human epidermal growth factor receptor-2 (HER2) directed therapy in patients with breast cancer (BC) has been growing within the last decade. Recently, the use of tyrosine kinase inhibitors (TKIs) has been of particular interest in the treatment of human malignancies. This literature commentary is intended to highlight the most recent findings associated with the widely-studied TKI agents and their clinical significance in improving the outcomes of HER2 positive BC.

Downregulation of angulin-1/LSR induces malignancy via upregulation of EGF-dependent claudin-2 and TGF-β-dependent cell metabolism in human lung adenocarcinoma A549 cells.

Abnormal expression of bicellular tight junction claudins, including claudin-2 are observed during carcinogenesis in human lung adenocarcinoma. However, little is known about the role of tricellular tight junction molecule angulin-1/lipolysis-stimulated lipoprotein receptor (LSR). In the lung adenocarcinoma tissues examined in the present study, expression of claudin-2 was higher than in normal lung tissues, while angulin-1/LSR was poorly or faintly expressed. We investigated how loss of angulin-1/LSR affects the malignancy of lung adenocarcinoma cell line A549 and normal human lung epithelial (HLE) cells. The EGF receptor tyrosine kinase inhibitor AG1478 prevented the increase of claudin-2 expression induced by EGF in A549 cells. Knockdown of LSR induced expression of claudin-2 at the protein and mRNA levels and AG1478 prevented the upregulation of claudin-2 in A549 cells. Knockdown of LSR induced cell proliferation, cell migration and cell metabolism in A549 cells. Knockdown of claudin-2 inhibited the cell proliferation but did not affect the cell migration or cell metabolism of A549 cells. The TGF-β type I receptor inhibitor EW-7197 prevented the decrease of LSR and claudin-2 induced by TGF-β1 in A549 cells and 2D culture of normal HLE cells. EW-7197 prevented the increase of cell migration and cell metabolism induced by TGF-β1 in A549 cells. EW-7197 prevented the increase of epithelial permeability of FITC-4kD dextran induced by TGF-β1 in 2.5D culture of normal HLE cells. In conclusion, downregulation of angulin-1/LSR induces malignancy via EGF-dependent claudin-2 and TGF-β-dependent cell metabolism in human lung adenocarcinoma.

Targeting Epidermal Growth Factor Receptor to Stimulate Elastic Matrix Regenerative Repair.

Abdominal aortic aneurysms (AAAs) represent a multifactorial, proteolytic disorder involving disintegration of the matrix structure within the AAA wall. Intrinsic deficiency of adult vascular cells to regenerate and repair the wall elastic matrix, which contributes to vessel stretch and recoil, is a major clinical challenge to therapeutic reversal of AAA growth. In this study, we investigate the involvement of epidermal growth factor receptor-mitogen activated protein kinase (EGFR-MAPK) pathway in the activation of aneurysmal smooth muscle cells (SMCs) by neutrophil elastase, and how EGFR can be targeted for elastic matrix regeneration. We have demonstrated that neutrophil elastase activates EGFR and downregulates expression level of key elastin homeostasis genes (elastin, crosslinking enzyme-lysyl oxidase, and fibulin4) between a dose range of 1-10 μg/mL (p < 0.05). It also incites downstream proteolytic outcomes by upregulating p-extracellular signal-regulated kinase (ERK)1/2 (p < 0.0001) and matrix metalloprotease 2 (MMP2) at a protein level, which is significantly downregulated upon EGFR-specific inhibition by tyrosine kinase inhibitor AG1478 (p-ERK1/2 and MMP2 [p < 0.05]). Moreover, we have shown that EGFR inhibition suppresses collagen amounts in aneurysmal SMCs (p < 0.05) and promotes robust formation of elastic fibers by enhancing its deposition in the extracellular space. Hence, the EGFR-MAPK pathway in aneurysmal cells can be targeted to provide therapeutic effects toward stimulating vascular matrix regeneration. Impact statement Proteolytic disorders such as aortal expansions, called abdominal aortic aneurysms (AAAs), are characterized by naturally irreversible enzymatic breakdown and loss of elastic fibers, a problem that has not yet been surmounted by existing tissue engineering approaches. In this work, we show, for the first time, how epidermal growth factor receptor (EGFR) inhibition provides downstream benefits in elastic fiber assembly and deposition in aneurysmal smooth muscle cell cultures. This work can open future possibilities for development of EGFR-targeted drug-based therapies not only for vessel wall repair in AAAs but also other proteolytically compromised elastic tissues.

Use of ALK-tyrosine kinase inhibitors (ALK TKI) in clinical practice, overall survival, and treatment duration – a Swedish nationwide retrospective study

Background The real-world treatment and outcomes of patients with anaplastic lymphoma kinase positive (ALK+) advanced non-small cell lung cancer treated with ALK Tyrosine Kinase Inhibitor (TKI) drugs in Sweden is not well described. Material and methods A retrospective population-based cohort study was conducted using Swedish national registers. All patients with a filled prescription for an ALK TKI between January 2012 and October 2020 were included. The sequencing of ALK TKI and duration of treatment (DOT) were described, and overall survival (OS) was estimated using the Kaplan–Meier method. Patients were stratified based on treatment with frontline chemotherapy, presence of CNS metastases prior to the first ALK TKI, and generation of ALK TKI agent. Results Among the total of 579 patients, 549 (95%) underwent a therapy sequence in line with current clinical practice with 204 (37%) patients receiving frontline chemotherapy. Single-line ALK TKI was given to 366 patients (crizotinib: 211; alectinib: 146; ceritinib: 9), whereas 128 patients received two different ALK TKI (frontline crizotinib: 100, alectinib: 24, ceritinib: 4); 40 patients received three lines and 15 patients four ALK TKI lines or more. With frontline chemotherapy, the mean (standard deviation) DOT was 1.07 (1.25) years for the entire TKI therapy sequence compared to 1.23 (1.28) years with frontline ALK TKI. The median (95% confidence interval) OS was 1.83 (1.48–2.13) years for the entire cohort, 1.44 (0.89–1.98) years for patients given frontline chemotherapy, and 2.02 (1.60–2.58) years for patients given frontline ALK TKI. Conclusion This study provides a unique overview of the patient population treated with ALK TKI in Sweden and reveals the treatment patterns applied in real clinical practice. More research is needed when longer follow-up data are available for later-generation ALK TKI, to fully understand ALK TKI sequencing and its effect on patient survival in a real-world setting.

CO45 Impact of Smoking Status on the Combination of Epidermal Growth Factor Receptor (EGFR) Tyrosine Kinase Inhibitors and Antiangiogenic Agents in Advanced Non-Small-Cell Lung Cancer Harbored Susceptible EGFR Mutation: A Systematic Review and Meta-Analysis

The aim of this study was to evaluate the impact of smoking status among non-small-cell Lung Cancer (NSCLC) patient receiving epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) alone or EGFR TKI plus antiangiogenic agents.

Combination of transarterial chemoembolization (TACE) and tyrosine kinase inhibitors (TKIs) compared to TACE alone as bridging therapy transplant recipients with hepatocellular carcinoma: An update.

e16201 Background: Hepatocellular carcinoma (HCC) is the world's sixth most prevalent cancer and the third leading cause of cancer-related death. For patients with advanced HCC, trials combining TACE with tyrosine kinase inhibitors (TKIs) such as Sorafenib have given mixed outcomes. (TACE) plus lenvatinib led showed significant improvement in OS compared to lenvatinib alone in the first-line setting in patients with advanced HCC according to phase 3 LAUNCH trial which was presented at the 2022 ASCO Gastrointestinal Cancers Symposium. This study was aimed to compare the outcome of HCC patients who received TACE plus TKI agent versus TACE alone. Methods: Retrospectively all subjects with unresectable HCC were included in this study, who underwent liver transplantation (LT) and were treated by either TACE alone (TA) or TACE plus Sorafenib (TandS) between July 2008–December 2021. For categorical factors, HCC recurrence after LT was reported as frequencies and proportions, while for continuous variables, the median and interquartile range (IQR) or mean was used. For categorical variables, Chi-square or Fisher's exact tests were used, while for continuous variables, Kruskal-Wallis test was used. Results: Seven hundred patients were screened; only 128 patients in total underwent LT with most being males (77%); the median age of 61.5 years. The TA group included 79 (77%) subjects who matched Milan Criteria (MC) and 24 (23%) who did not, but the TandS group had a greater number of cases who did not meet MC: 16 (64%) versus 9 (36%); p = 0.01. There was a significant variation in five-year disease-free survival (DFS) across the therapy groups investigated, with 100% DFS in the TandS group vs 67.2 percent in the TAne group (p = 0.07). The TandS group had a five-year patient survival rate of 77.8% compared to 61.5 percent in the TA group (p = 0.51). However, beyond the MC, patients who were treated with TA had the average percentage of necrotic tumor on resected histology of 43.8 %, 32 % compared to 69.6 %, 32.8 % for cases treated with TandS, p = 0.03. Conclusions: We have found that using TandS is generally well tolerated and demonstrated improved OS compared to TA in patients with unresectable HCC. A prospective clinical study (NCT05171335) is ongoing at our institution to further investigate this concept.

Dexmedetomidine-Induced Aortic Contraction Involves Transactivation of the Epidermal Growth Factor Receptor in Rats.

In this study, we examined whether aortic contraction, induced by the alpha-2 adrenoceptor agonist dexmedetomidine, is involved in the transactivation of the epidermal growth factor receptor (EGFR) in isolated endothelium-denuded rat aortas. Additionally, we aimed to elucidate the associated underlying cellular mechanisms. The effects of the alpha-2 adrenoceptor inhibitor rauwolscine, EGFR tyrosine kinase inhibitor AG1478, Src kinase inhibitors PP1 and PP2, and matrix metalloproteinase inhibitor GM6001 on EGFR tyrosine phosphorylation and c-Jun NH2-terminal kinase (JNK) phosphorylation induced by dexmedetomidine in rat aortic smooth muscles were examined. In addition, the effects of these inhibitors on dexmedetomidine-induced contraction in isolated endothelium-denuded rat aorta were examined. Dexmedetomidine-induced contraction was inhibited by the alpha-1 adrenoceptor inhibitor prazosin, rauwolscine, AG1478, PP1, PP2, and GM6001 alone or by a combined treatment with prazosin and AG1478. AG1478 (3 × 10−6 M) inhibited dexmedetomidine-induced contraction in isolated endothelium-denuded rat aortas pretreated with rauwolscine. Dexmedetomidine-induced EGFR tyrosine and JNK phosphorylation were inhibited by rauwolscine, PP1, PP2, GM6001, and AG1478. Furthermore, dexmedetomidine-induced JNK phosphorylation reduced upon EGFR siRNA treatment. Therefore, these results suggested that the transactivation of EGFR associated with dexmedetomidine-induced contraction, mediated by the alpha-2 adrenoceptor, Src kinase, and matrix metalloproteinase, caused JNK phosphorylation and increased calcium levels.

Morphologic-Molecular Transformation of Oncogene Addicted Non-Small Cell Lung Cancer.

Patients with non-small cell lung cancer, especially adenocarcinomas, harbour at least one oncogenic driver mutation that can potentially be a target for therapy. Treatments of these oncogene-addicted tumours, such as the use of tyrosine kinase inhibitors (TKIs) of mutated epidermal growth factor receptor, have dramatically improved the outcome of patients. However, some patients may acquire resistance to treatment early on after starting a targeted therapy. Transformations to other histotypes—small cell lung carcinoma, large cell neuroendocrine carcinoma, squamous cell carcinoma, and sarcomatoid carcinoma—have been increasingly recognised as important mechanisms of resistance and are increasingly becoming a topic of interest for all specialists involved in the diagnosis, management, and care of these patients. This article, after examining the most used TKI agents and their main biological activities, discusses histological and molecular transformations with an up-to-date review of all previous cases published in the field. Liquid biopsy and future research directions are also briefly discussed to offer the reader a complete and up-to-date overview of the topic.

Growth factor dependence of the proliferation and survival of cultured lacrimal gland epithelial cells isolated from late-embryonic mice.

Epidermal growth factor (EGF) and hepatocyte growth factor (HGF) regulate the growth and morphogenesis of various exocrine glands with branched morphologies. Their roles in lacrimal gland (LG) development remain unknown, but fibroblast growth factor (FGF) 10 is crucial for early LG organogenesis. To clarify the roles of EGF, HGF, and FGF10 in LG development, LG epithelial cells were isolated from late-embryonic and neonatal mice; cultured; and treated with EGF, HGF, or FGF10 and their respective receptor tyrosine kinase (RTK) inhibitors AG1478, PHA665752, or SU5402. EGF and HGF increased the number of viable cells by enhancing DNA synthesis, FGF10 and SU5402 showed no such effect, and RTK inhibitors exhibited the opposite effect. EGF and HGF receptors were immunostained in cultured late-embryonic LG epithelial cells and terminal LG acini from late embryos and adult mice. HGF was detected in neonatal LG epithelial cell culture supernatants by western blotting. In the absence of EGF and HGF RTK inhibitors, growth factor addition increased the number of viable cells and suppressed cell death. However, when one RTK was inhibited and a growth factor targeting an intact RTK was added, the number of dead cells increased as the number of viable cells increased. No cells survived when both RTKs were inhibited. In explant cultures of LGs from embryos, AG1478 or PHA665752 decreased the number of Ki67-positive proliferating epithelial cells in terminal acini. Thus, EGF and HGF may function in a cooperative autocrine manner, supporting cell proliferation and survival during LG development in late-embryonic and neonatal mice.

Single cell phenotyping of PDL1 and HLA1 on circulating tumor cells (CTC) in clear cell renal cell carcinoma (ccRCC) on systemic treatment with immunotherapy (IO) and vascular endothelial growth factor receptor tyrosine kinase inhibitors (TKI).

381 Background: Single agent or combination regimens using different IO and TKI agents have dramatically improved survival of patients (pt) with advanced ccRCC. Nevertheless, selecting optimal combination and sequencing of treatments remains challenging given the current absence of predictive biomarkers. Considering substantial disease heterogeneity and tumor clonal evolution, CTCs could provide a more comprehensive and longitudinal assessment of disease and response to treatment when compared to single site biopsy. In this study we explore changes in CTC characteristics in correlation with pt’s response (Resp) to treatment and progression (PD). Methods: 152 blood sample time points from 44 ccRCC pts (mean=3.5 sample/pt, range= 1-9) were included. An automated microfluidic platform using exclusion-based sample technology was employed for high sensitivity enrichment of RCC CTCs using EpCAM and CAIX antibodies. High-specificity CTC identification was achieved with positive staining for pCK or CAXII, and negative staining for CD45, CD34 and CD66b. Single cell phenotyping of PDL1 and HLA1 expression on each CTC was quantified with automated image analysis algorithms followed by manual visual QA of the putative CTCs. Cellular-level expression of PDL1 and HLA1 were compared within treatment-response groupings, using Wilcoxon rank-sum tests (Table). Results: Pts were 70% male, 93% Caucasian, 51% de novo metastatic, 98% received systemic treatment. CTC samples were collected at baseline (12) or while on treatment with IO (71), TKI (55), or IO/TKI (14). Across treatments, the number of CTCs increased from Resp to PD but this trend was not statistically significant. PDL1 expression was higher at PD compared to Resp on IO and IO/TKI but not significantly different on TKI. HLA1 expression was higher at PD compared to Resp on IO and TKI but not significantly different on IO/TKI. Average CTC PD-L1 expression was higher at Resp to IO compared to baseline. Conclusions: Single cell phenotyping of PDL1 and HLA1 were done at Resp compared to PD time points on IO and/or TKI to identify potential mechanisms of resistance. Further evaluation of these preliminary results in prospective trials is ongoing to advance new predictive biomarkers for ccRCC.[Table: see text]

Efficacy of tyrosine kinase inhibitors (TKI) after combination ipilimumab plus nivolumab (I/N) in metastatic clear cell renal cell carcinoma (ccmRCC) patients: Results from the Canadian Kidney Cancer Information System (CKCis).

346 Background: The use of I/N is a proven first-line option for patients with intermediate/poor IMDC prognostic criteria. The use of vascular endothelial growth factor inhibitors such as sunitinib have shown activity in the treatment of ccmRCC, but their effectiveness post I/N needs better characterization. This study aims to demonstrate the efficacy of sunitinib, and other TKI agents post I/N in ccmRCC in a real world setting. Methods: Patients with ccmRCC who had received I/N and were subsequently treated with TKI between Jan 1, 2011 and December 31, 2019 were identified from CKCis. Time to treatment failure (TTF – time from start of first subsequent TKI to discontinuation for any reason) and overall survival (OS) – time from first subsequent TKI to death) were calculated using the Kaplan-Meier method. Cox regression was performed to adjust for IMDC criteria. RECIST criteria was used to determine best overall response (ORR) of TKI radiographically. Results: 64 patients were treated with TKI post I/N. Characteristics and outcomes are listed in the table. Of the second-line TKI patients, 51 received sunitinib, 10 received pazopanib and 3 received other TKI. Reasons for second-line TKI discontinuation are: 28% toxicity, 34% progression, 7% other reasons while 31% remain on treatment. Median follow-up time was 12.9m. ORR for second-line TKI overall and second-line sunitinib was 30.0% and 29.4%, respectively. Conclusions: These data show that TKI are active after I/N in ccmRCC. TTF may underestimate PFS due to the large number of patients discontinuing treatment for toxicity and not progression. Efficacy of second-line TKI post I/N in this dataset is similar that of first-line sunitinib from recent randomized phase III trials, suggesting that there may be no significant loss of TKI activity after having received first-line I/N. Overall, these data support the use of TKI after I/N.[Table: see text]

Surgery After Conversion Therapy With PD-1 Inhibitors Plus Tyrosine Kinase Inhibitors Are Effective and Safe for Advanced Hepatocellular Carcinoma: A Pilot Study of Ten Patients.

Background and AimsImmunotherapy with PD-1 inhibitors combined with tyrosine kinase inhibitors (TKIs) has been proven to be effective against advanced hepatocellular carcinoma (HCC). The aim of this study was to identify the feasibility and safety of subsequent salvage surgery after this combination therapy.Methods and PatientsA retrospective analysis was performed on patients with primary HCC with major vascular invasion between 2018 and 2019. All cases were treated with a combination of a PD-1 inhibitor and TKI agents and subsequent surgery.ResultsA total of 10 HCC cases with major vascular invasion met the successful conversion criteria after the combination therapy, and eight patients underwent subsequent salvage surgery after both radiology and 3D quantitative oncological assessment. Partial response (PR) was recorded in 7 of 10 patients and complete response (CR) in 3 of 10 patients before salvage surgery. Salvage surgery included right hepatectomy, left hepatectomy, and anatomic segmental hepatectomy. The mean intraoperative blood loss was 1,650 ml (50–3,000 ml). No complications beyond Clavien–Dindo level III or postoperative mortality were observed. The viable tumor cell rate of the PR cases (modified response evaluation criteria in solid tumors, mRECIST) varied from 1.5% to 100%, and only one patient had pathology-proven pathological complete response (pCR). The postoperative median follow-up time was 19.7 months (9.1–24.9 months). The 12-month recurrence-free survival rate of all cases who underwent salvage surgery was 75%.ConclusionSalvage surgery was effective and safe after conversion therapy with PD-1 inhibitors plus TKIs and may increase the long-term oncological benefit for patients with unresectable HCC.

Tyrosine Kinase Inhibitors for Acute Respiratory Failure Because of Non–small-Cell Lung Cancer Involvement in the ICU

Tyrosine Kinase Inhibitors for Acute Respiratory Failure Because of Non–small-Cell Lung Cancer Involvement in the ICU