Metastatic Solid Cancers Research Articles

Clinical cell-surface targets in metastatic and primary solid cancers.

Therapies against cell-surface targets (CSTs) represent an emerging treatment class in solid malignancies. However, high-throughput investigations of CST expression across cancer types have been reliant on data sets of mostly primary tumors, despite therapeutic use most commonly in metastatic disease. We identified a total of 818 clinical trials of CST therapies with 78 CSTs. We assembled a data set spanning RNA-seq and microarrays in 7,927 benign samples, 16,866 primary tumor samples, and 6,124 metastatic tumor samples. We also utilized single-cell RNA-seq data from 36 benign tissues and 558 primary and metastatic tumor samples, and matched RNA versus protein expression in 29 benign tissue samples, 1,075 tumor samples, and 942 cell lines. High RNA expression accurately predicted high protein expression across CST therapies in benign tissues, tumor samples, and cell lines. We compared metastatic versus primary tumor expression, identified potential opportunities for repositioning, and matched cell lines to tumor types based on CST and global RNA expression. We evaluated single-cell heterogeneity across tumors, and identified rare normal cell subpopulations that may contribute to toxicity. Finally, we identified combinations of CST therapies for which bispecific approaches could improve tumor specificity. This study helps better define the landscape of CST expression in metastatic and primary cancers.

Capture of live circulating tumor cells via unique surface charges from cancer patients by a novel nanotechnology

AbstractCirculating tumor cells (CTCs) serve as a pivotal foundation for both fundamental oncological research and the precise evaluation of therapeutic interventions. However, the isolation of CTCs from clinical blood samples presents a multitude of sophisticated challenges, predominantly associated with the specificity of biomarkers and the sensitivity of detection techniques. In our previous study, we proposed a novel detection concept for CTCs based on a signature biophysical feature on the surface of cancer cells: a negative charge regulated by glycolytic processes. In this study, we have conducted experiments to ascertain the efficacy of this proposed method in capturing CTCs from clinical blood samples of individuals afflicted with solid tumors and leukemia. Our findings indicate that the method is capable of isolating tens of thousands of viable cancer cells from various metastatic solid cancers and leukemia using a mere 1 mL of blood. These cells were enumerated using cytological imaging that identified morphological characteristics indicative of malignancy. The outcomes of our study suggest that the negatively charged surface of cancer cells is a ubiquitous trait across both cultured cancer cell lines and fresh blood samples derived from cancer patients. Moreover, the capture technology employed in this study demonstrated superior performance in comparison to antecedent methodologies, enhancing the detection and documentation of CTCs for subsequent verification and analysis. This advancement holds significant promise for the improvement of diagnostic accuracy and the monitoring of therapeutic responses in oncology.

Healthcare Professionals' Views of Supportive Care Needs for Chinese, Korean, and Vietnamese Americans with Metastatic Cancer.

The supportive care needs of people with metastatic cancer, particularly Asian Americans, are understudied. Distinct psychosocial support needs may exist across ethnocultural groups with Confucian-heritage values and norms. Cultural factors may shape how adults approach their oncologic care. This qualitative study represents the perspectives of 15 experienced healthcare professionals about the supportive care needs of Chinese-, Korean-, and Vietnamese-heritage (CKV) adults with metastatic solid cancers. Reflexive thematic analysis was conducted with transcripts from three semi-structured focus groups and five parallel-format individual interviews. Inductive coding and iterative theme development resulted in four themes describing the types of needs (basic, care-related, mental health, relational trust) that should be met for CKV patients with metastatic cancer, which may fall through the gaps when the healthcare system and patient's differing cultural contexts collide. In conclusion, greater involvement of psychosocial care specialists with cultural expertise is essential to promote patients' and families' well-being, prevent care disparities, and better support the healthcare team. Systemic changes that increase workforce diversity, reduce language and insurance barriers, and allow healthcare professionals to build relational trust with patients, are needed to improve quality of life for CKV patients with metastatic cancer.

A phase II study of tepotinib in patients with advanced solid cancers harboring MET exon 14 skipping mutations or amplification (KCSG AL19-17)

We evaluated the efficacy and safety of tepotinib in patients with various solid cancers harboring MET exon 14 skipping mutation (METex14) or MET gene amplification. A phase II, multicenter study was conducted in patients with advanced or metastatic solid cancers who progressed after standard treatment, harboring either METex14 or MET amplification detected in tissue-based next-generation sequencing (NGS). The primary endpoint was objective response rate (ORR). For exploratory analyses, we analyzed the gene profiles using plasma NGS test. Thirty-five patients were enrolled. The ORR was 57.6% for all patients, 52.2% for those with METex14, and 70% for those with MET amplification. Median progression-free survival (PFS) was 8 months [95% confidence interval (CI) 4.5-11.5 months] and median overall survival (OS) was 14 months (95% CI 7.8-20.2 months) in all patients. For patients with non-small-cell lung cancer with METex14, the median PFS was 9 months (95% CI 4.7-13.4 months) and the median OS was 17 months [95% CI not applicable (NA)-NA]. For patients with MET amplification, the median PFS was 7 months (95% CI 1.5-12.5 months) and the median OS was 10 months (95% CI 5.8-14.2 months). The ORR of patients with MET dysregulation detected by plasma NGS was 72.2%, whereas the ORR was 30% in those without detection. The most common adverse events were peripheral edema, asthenia, transaminase elevation, and anorexia, mostly grade 1 or2. Tepotinib demonstrated consistent antitumor activity in patients with METex14, and promising antitumor activity in various cancers with MET amplification. Detection of MET dysregulation by plasma NGS may predict the response to tepotinib.

PD-1 inhibitor combined with SBRT, GM-CSF, and thymosin alpha-1 in metastatic breast cancer: A case report and literature review.

Triple-negative breast cancer is characterized by a worse prognosis compared with other breast cancer subtypes, especially in the case of pretreated metastatic triple-negative breast cancer (mTNBC). Because of the limited treatment options and suboptimal response rates, there is a pressing need to explore novel treatment protocols. A 48-year-old female patient diagnosed with mTNBC who had not responded to multiple lines of therapy (including surgery, chemotherapy, and radiotherapy) but demonstrated significant efficacy and abscopal effects after enrolling in our clinical trial. Triple-negative breast cancer with lung metastases. The clinical trial combined stereotactic body radiotherapy, immunotherapy, granulocyte-macrophage colony-stimulating factor, and thymosin alpha-1 to treat previously treated metastatic solid cancers. This combined treatment regimen implemented in this clinical trial yielded the patient's notable efficacy, accompanied by abscopal effects. The target lesion and the 3 observed lesions achieved a partial response according to the RECIST v1.1 criteria. reevaluation scans after 2 cycles of immunotherapy indicated a regression rate of -78.97% for the target lesion and -56.73% for the observed lesions. Hematological indexes were stable, and there was no apparent myelosuppression. Also, the tumor marker CA-199 exhibited a downward trend. During the course of treatment, the patient experienced a grade 2 skin reaction, which improved after receiving antiallergic treatment. No further adverse effects were observed. This treatment regimen may offer a promising treatment strategy for patients with mTNBC and other metastatic solid cancers.

Changes in serum lactate dehydrogenase as a prognostic factor in patients with head and neck squamous cell carcinoma treated with immune checkpoint inhibitors

Background Lactate dehydrogenase (LDH) is involved in the Warburg effect. Elevated serum LDH is a prognostic marker for metastatic solid cancer. Aim To investigate the prognostic impact of serum LDH in patients with head and neck squamous cell carcinoma treated with immune checkpoint inhibitors (ICIs). Materials and Methods This retrospective study included 129 patients treated with ICIs between 2017 and 2023. The effects of pretreatment LDH, LDH at 3 months, and change in LDH during the first 3 months (ΔLDH) on overall survival (OS) and progression-free survival (PFS) were analyzed using the Kaplan–Meier method and Cox regression model. Results The 1-year PFS and OS rates for high and low groups were 6.0% and 30.1% for pretreatment LDH (p = 0.044), 25.7% and 38.3% for on-treatment LDH (p = 0.079), and 14.3% and 38.7% for ΔLDH (p = 0.008), as well as 42.1% and 60.9% for pretreatment LDH (p = 0.109), 56.0% and 80.5% (p < 0.001) for on-treatment LDH, and 31.0% and 81.0% for ΔLDH (p < 0.001), respectively. ΔLDH was an independent prognostic factor for both PFS and OS. Conclusions and Significance ΔLDH can be used to predict ICI treatment outcomes and as a marker in deciding to continue ICI therapy.

The effect of examining somatic alterations with NGS in patients with solid tumors, on patient management: A single-center experience in Turkey.

This study aimed to investigate the impact of analyzing somatic alterations using next-generation sequencing (NGS) on treatment management in patients with metastatic solid cancers and their ability to access NGS recommended treatments. This retrospective study included eligible patients who underwent NGS on somatic tumor tissue. We examined the clinical and pathological characteristics of these patients and the alterations in their treatment following NGS results. A total of 101 patients who underwent NGS were included in the study. The most common cancers were non-small cell lung cancer (NSCLC), colorectal, and breast cancers, in that order. The median age was 58 (range 21-82) years, with 60 (59.4%) male participants. The median NGS turnaround time was 23 (range 17-29) days. NGS was performed on tissue from the primary lesion in 89(88%) patients. Predictive, prognostic, actionable, or variants of unknown significance were detected in 62(61.4%) patients. The most frequent variants identified were KRAS, EGFR, TP53, PIK3CA, and other rare mutations. Treatment was altered in 17(16.8%) patients based on NGS results. Of the 30 (29.7%) patients for whom NGS-informed treatment was recommended, only seven (6.9%) received the recommended therapy. There was no significant difference in overall survival (OS) between patients whose treatment was changed based on NGS results and those whose treatment remained unchanged (p = 0.897). There was no difference in OS between patients with and without variants (p = 0.384). NGS analysis of somatic alterations in patients with metastatic cancer may reveal additional variants beyond those identified by baseline tests. However, based on the recommendations of the reimbursement institution in Turkey, only a limited number of patients are able to access treatments recommended by NGS results. Therefore, baseline tests established in Turkey need to be made available in more centers in an appropriate time.

Fecal microbiota transplantation improves anti-PD-1 inhibitor efficacy in unresectable or metastatic solid cancers refractory to anti-PD-1 inhibitor

The gut microbiome significantly influences immune responses and the efficacy of immune checkpoint inhibitors. We conducted a clinical trial (NCT04264975) combining an anti-programmed death-1 (PD-1) inhibitor with fecal microbiota transplantation (FMT) from anti-PD-1 responder in 13 patients with anti-PD-1-refractory advanced solid cancers. FMT induced sustained microbiota changes and clinical benefits in 6 of 13 patients, with 1 partial response and 5 stable diseases, achieving an objective response rate of 7.7% and a disease control rate of 46.2%. The clinical response correlates with increased cytotoxic Tcells and immune cytokines in blood and tumors. We isolated Prevotella merdae Immunoactis from a responder to FMT, which stimulates Tcell activity and suppresses tumor growth in mice by enhancing cytotoxic Tcell infiltration. Additionally, we found Lactobacillus salivarius and Bacteroides plebeius may inhibit anti-tumor immunity. Our findings suggest that FMT with beneficial microbiota can overcome resistance to anti-PD-1 inhibitors in advanced solid cancers, especially gastrointestinal cancers.

Analytical validation of the Labcorp Plasma Complete test to enable precision oncology through solid tumor liquid biopsy comprehensive genomic profiling.

3063 Background: To help guide treatment decisions and enable clinical trial matching for cancer patients, tumor genomic profiling is an essential precision oncology tool. Liquid biopsy may be used as a complementary approach to assess tumor-specific DNA alterations circulating in the blood. The Labcorp Plasma Complete test is a next-generation-sequencing (NGS), cell-free DNA (cfDNA) comprehensive genomic profiling test that identifies actionable and clinically relevant variants in advanced and metastatic solid cancers across 521 genes. Methods: The Labcorp Plasma Complete test is a hybrid capture based, targeted NGS test, optimized for 25 ng of cfDNA input and is intended for variant detection in all solid cancer indications. The test interrogates all coding exons of 521 genes to comprehensively detect single nucleotide variants (SNVs) and insertion and deletions (indels). The test also reports copy number amplifications (CNAs) and gene translocations in 12 genes, and microsatellite instability (MSI). In total, 631 cancer patient plasma samples were evaluated by the test including lung, breast, colorectal, head and neck, pancreatic, gynecologic, and prostate cancers among other indications. Well-characterized reference samples (Genome in a Bottle) were utilized to assess analytical specificity. Contrived cell lines and clinical samples were utilized to establish analytical sensitivity, accuracy, as well as precision, reproducibility, and repeatability (PRR). Results: The test yielded results for 98.3% (620/631) of cases and identified variants in 94.7% (587/620) with a median of 6 variants per case. Clinically actionable variants were detected in 42.1% of clinical samples. Analytical specificity was ≥99.9999% for SNVs and 100% for indels, CNAs, translocations, and MSI. Analytical sensitivity (limit of detection, 95%) was verified for each variant type, with a median variant allele frequency (VAF) of 1.42% for SNVs and 1.43% for indels, 1.7-fold for amplifications, 0.35% fusion read fraction for translocations, and 0.82% VAF for MSI. The intra-laboratory PRR study resulted in 94.9% average percent agreement (APA) and 99.9% average negative agreement (ANA) for sequence variants (SNVs and indels) and 100% APA and ANA for CNAs, translocations, and MSI. Orthogonal assays including other NGS tests and digital PCR were utilized to assess Labcorp Plasma Complete accuracy which demonstrated an aggregate analytical concordance of 96.28% positive percent agreement and &gt;99.9999% negative percent agreement for all variants. Conclusions: The analytical validation of the Labcorp Plasma Complete test demonstrates that the liquid biopsy approach is highly sensitive, specific, accurate, reproducible, and robust for comprehensive genomic profiling to complement tissue-based testing and inform clinical decision making.

EGFR mutation testing trends for patients with metastatic, non-squamous non-small cell lung cancer (non-SQ NSCLC) in Queensland, Australia from 2014-2021.

e13505 Background: Lung cancer is the leading cause of cancer-related mortality worldwide. Epidermal growth factor receptor (EGFR) is the most common actionable mutation in non-small cell lung cancer (NSCLC) with routine testing recommended globally. In late 2013, screening for EGFR mutations was publicly funded in Australia for metastatic non-SQ-NSCLC. However, timely EGFR results are not universally available, often limited by tissue quantity/quality or prolonged turnaround times. This in turn affects access to treatment and thus survival. Methods: We aimed to examine the rates of EGFR testing over time and explore factors impacting results. Cases were identified from the Queensland Oncology Repository, a clinical database consolidating diagnostic, treatment and outcome data for all Queenslanders with cancer through the Queensland Cancer Registry. Cases were included if they had metastatic non-SQ-NSCLC, EGFR testing available via Pathology Queensland, and no other metastatic solid organ cancer within 1 year. Primary outcomes were EGFR mutation testing rates and time from first biopsy to EGFR mutation result, stratified by year of diagnosis and rurality. Results: A total of 3369 cases were included, of which 2871 had EGFR testing. The EGFR mutant (mt) rate was 12.6%, while 16.1% of cases had no EGFR results. Of cases without a conclusive EGFR result, reasons included: 179 transitioned to best supportive care before testing, 208 with insufficient tissue for a conclusive result, and 155 without testing for unclear reasons. The average time from biopsy to EGFR result improved from 29.9 days in 2014 to 21.5 days in 2021, with no significant difference in time to result between major cities, regional or remote areas. Cases with no EGFR results were more prevalent in rural areas. The proportion of patients living in outer regional/remote areas with no EGFR result was 21.1% compared to 15.5% in those living in major cities/inner regional sites. This was a relative increase of 36.2% (95% CI: 10.1% - 68.6%), a significant result (χ2 = 7.7483, p=0.005). Cases with no EGFR results in outer regional and remote sites declined from 30.1% in 2014-2015 to 15.3% in 2020-2021. Conclusions: EGFR mutation testing and result time has improved since 2014. Though time to result was not affected by rurality, significantly more rural patients lacked conclusive EGFR data, highlighting a gap in access to care. The cumulative EGFR no result rate of 16% and result time of 24 days indicates health systems need to more rapidly adapt to new treatment paradigms, particularly in the era of targeted therapies. [Table: see text]

Integrated analysis of two phase 2 trials of nivolumab in metastatic rare solid cancer with dMMR or pMMR (MASTER KEY sub-studies: ROCK and ROLL trial).

e14603 Background: Immune checkpoint inhibitors play a critical role in mismatch repair deficient (dMMR) / microsatellite instability-high (MSI-H) cancers, but has yet to investigate the activity of nivolumab in a subset of rare cancers (incidence &lt; 6 / 100,000/year), that are MMR proficient (pMMR). Methods: We conducted two single arm phase 2 trials to investigate the efficacy and safety of nivolumab monotherapy in patients with advanced rare tumors with either pMMR (jRCT2091220345) or dMMR (jRCT2091220344). dMMR was defined by the complete loss of at least one of the following proteins: MLH1, MSH2, MSH6, PMS2. pMMR was defined when all four proteins were retained. Primary endpoint was independently reviewed response rate (RR). Secondary endpoints included progression free survival (PFS), overall survival (OS), and adverse events (AE). The dMMR/MSI-H trial enrolled 5 to 15 patients, based on a Bayesian design with a threshold RR of 5% and an expected RR of 30%, requiring ≥2 responders to achieve a posterior probability of ≥95% that the true RR of nivolumab is at least 5%. The pMMR trial was designed to explore the clinical activity in patients with pMMR, but also to confirm the clinical significance of “dMMR/MSI-H” as a predictive marker. If the upper limit of 95% confidence interval of the objective RR in the pMMR trial is below 30%, it implies that dMMR/MSI-H serves as a predictive marker. To evaluate this hypothesis at one-sided significance level of 5% with 90% power, a sample size of 54 patients with pMMR is necessary, assuming that the expected RR of nivolumab to be 15%. Results: Between May 2018 and March 2021, 11 and 57 patients received nivolumab treatment in the dMMR/MSI-H trial and pMMR trial, respectively. 10 and 54 patients in the respective trials were included in the full analysis set. The objective RR was 60% (95% CI 26.2-87.8) and 5.6% (95% CI 1.2-15.4) in the dMMR/MSI-H trial and pMMR trial, respectively. Median PFS was 10.1 months (95% CI 0.9-NE), and median OS was not yet reached in the dMMR/MSI-H trial, while the median PFS was 2.5 months (95% CI 1.9-4.8), and median OS was 12.7 months (95% CI 8.1-18.5) in the pMMR trial. Histology of the three responders in the pMMR trial were adnexal carcinoma of skin (2/4, 50%), and soft tissue sarcoma (1/14, 7.1%). In dMMR/MSI-H patients with tumor mutation burden (TMB) data, 5 of 6 were TMB ≥ 10/Mb, all of whom showed response. In contrast, in the pMMR group, two of the 22 patients with TMB data had TMB &gt; 10/Mb, but neither showed response. Treatment-related grade 3 or higher AEs were observed in 0 and 8 (14%) patients in the dMMR/MSI-H and pMMR trials, respectively. Conclusions: Clinical benefit of nivolumab in pMMR advanced rare cancer patients was limited in contrast to dMMR/MSI-H patients, confirming the clinical significance of dMMR/MSI-H as a predictive marker. Further predictive biomarker studies are needed for pMMR tumors. Clinical trial information: jRCT2091220345 , jRCT2091220344 .

Outcomes of patients with metastatic solid cancers treated on early phase clinical trials in western Australia.

e23094 Background: Cancer drug development is flourishing with novel immunotherapy combinations, antibody drug conjugates and increasingly molecularly targeted therapies that have pushed the inclusion of phase I clinical trials into earlier lines of systemic treatment. Linear Clinical Research is a dedicated Phase I centre with a catchment area of over 3 million people. We conducted a retrospective review into the outcomes of our centre. Methods: We included patients between 01/01/2020 to 30/04/2023, with advanced/metastatic or rare cancers with no available or suitable standard of care treatment. Data were extracted from our internal database with minimum follow up of 6 months. The primary endpoint was overall survival (OS). Other endpoints included progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), time to response (TTR), duration of response (DOR), duration of treatment (DOT), post-treatment survival (PTS), and 90-day mortality. Subgroup analyses based on treatment type were performed. Multivariate cox regression analysis was performed as part of tertiary endpoints. Results: 251 patients were recruited to 53 trials. Median age : 61 years (range: 21-83 years), 54.6% female, 74.1% Caucasian, ECOG 0-1: 90.8%, 26.7% rare cancers, 52.2% had 0-1 line of previous treatment, 47.8% had ≥ 2 lines. Trial treatments were: 51.4% immunotherapy (IO), 30.7% targeted therapy matched to molecular findings (TT), 2.8% antibody drug conjugate (ADC), 12.7% combination therapy (IO/TT/ADC/chemotherapy), 2.0% endocrine therapy alone, and &lt; 1% chemotherapy. At data cut-off, 129 OS events had occurred (56.0%, median follow up of 22.0 months).The median OS was 16.0 months (95% CI 11.1 - 20.9), median PFS: 3.0 months (95% CI 2.2 - 3.8), ORR: 23.6%, DCR: 67.3%, median TTR: 2.0 months (IQR: 1.0-3.0), median DOR: 14.0 months (IQR: 6.0-38.0), median DOT: 3.0 months (IQR 1.0-10.0), median PTS: 7.0 months (IQR 2.0-27.0), 90-day mortality: 17.7%. Median OS based on treatment type: 11.0 months (95% CI 5.7-16.3) (IO), 12.0 months (95% CI 1.6-22.4) (TT), median not reached (range :1.0-28.0) (ADC), and 19.0 months (95% CI 13.6-24.4) (combination therapy). Median PFS based on treatment type: 2.0 months (95% CI 1.2-2.8) (IO), 5.0 months (95% CI 2.5-7.5) (TT), 10.0 months (95% CI: 0.0-28.0) (ADC), 6.0 months (95% CI 2.2 - 9.8) (combination therapy). Multivariate Cox analysis showed that higher number of lines of previous treatment was negatively associated with PFS and OS when adjusted for age, gender, type of treatment, and baseline sum of diameter (SOD). Conclusions: Our overall OS, ORR, and DCR are better than historical data of phase 1 during chemotherapy era , and are comparable to other centers nationally and internationally. Further work needs to be done to improve survival outcomes including algorithms to better match patients and trials earlier in their disease course.

CtDNA as a biomarker in phase II study of tepotinib in advanced solid cancers with MET exon 14 skipping mutation or amplification (KCSG AL19-17).

3050 Background: Tepotinib consistently demonstrated antitumor activity in patients with MET exon 14 skipping mutation ( METex14) and promising activity in various cancers with MET amplification, according to previous reports. We assessed plasma ctDNA as a potential biomarker in MET-dysregulated advanced cancer patients with tepotinib treatment. Methods: KM-08 (KCSG AL19-17, NCT04647838) was a phase 2, multicenter study with tepotinib treatment for patients with advanced or metastatic solid cancers harboring either METex14 or MET amplification detected in tissue-based next-generation sequencing (NGS). For exploratory analyses, we analyzed the genetic profile using liquid-based NGS testing with AlphaLiquid-100 panel (IMBdx Inc. Seoul, KR) at baseline (T0), after six weeks during treatment (T1), and at the time of disease progression (T2). Results: Baseline ctDNA NGS data was available in 28 (80%) out of 35 patients enrolled in the trial. Among them, METex14 or MET amplification was detected in 18 patients, with a sensitivity of 64.3%. The most commonly co-mutated gene was TP53, followed b y PIK3CA, ATM, MYCN, and KRAS. The objective response rate (ORR) in plasma MET positive (PM+) patients was higher (81.2%) than the ORR in plasma MET negative (PM−) patients’ group (30.0%). In contrast, PM− group had a longer progression-free survival (PFS) and overall survival (OS) than PM+ group. PFS was 11.0 months (95% CI 8.1, 13.9) vs 6.0 months (95% CI 3.6, 8.3) and OS was NR vs 14.0 months (95% CI 4.7, 23.3), respectively. The molecular responder (MR, MET alteration variant allele frequency [VAF] T1/T0 &lt;50%) was 80.0% (12/15 patients), and the molecular non-responder (MNR, METVAF T1/T0≥50%) was 20.0% (3/15 patients). ORR was higher in the MR group (91.7%) than in the MNR group (33.3%). PFS and OS were longer in the MR group than in the MNR group, 6.0 months (95% CI 0.0, 14.5) vs 3.0 months (95% CI 1.4, 4.6) with P= 0.114 and NR vs 4.0 months (95% CI 2.4, 5.6) with P= 0.067, respectively. Out of the 20 patients with samples available at T2, one had an on-target mutation on MET (D1228N, and Y1230H) while two had off-target emerging oncogenic alterations in KRAS, BRAF, and ERBB2 genes. Conclusions: In the liquid biomarker analysis in the MET-dysregulated cancer patients who were treated with tepotinib, the presence of ctDNA METalteration at baseline was associated with a higher response rate but shorter PFS and OS. The molecular response was well correlated with the radiological response and associated with better outcomes. (Funded by Merck KGaA, Darmstadt, Germany, ClinicalTrials.gov number, NCT04647838.) Clinical trial information: NCT04647838 .

Neoantigen-specific stimulation of tumor-infiltrating lymphocytes enables effective TCR isolation and expansion while preserving stem-like memory phenotypes

BackgroundTumor-infiltrating lymphocytes (TILs) targeting neoantigens can effectively treat a selected set of metastatic solid cancers. However, harnessing TILs for cancer treatments remains challenging because neoantigen-reactive T cells are often rare...

Neutropenic Sepsis in the Intensive Care Unit: Differences in Clinical Profile and Outcomes According to the Cause of Neutropenia.

Neutropenic sepsis frequently requires admission to an intensive care unit (ICU). Differences between subgroups of patients with neutropenic sepsis are not well characterized. To investigate clinical outcomes among patients with neutropenic sepsis and hematological malignancy, metastatic solid cancer, or no cancer diagnosis. Retrospective cohort study of all patients admitted to ICU in Australia or New Zealand between January 2000 and December 2022 with a primary admission diagnosis of sepsis and total white cell count <1.0 × 109 cells/L. We identified 8617 ICU admissions with neutropenic sepsis (hematological malignancy n = 4660; metastatic solid cancer n = 1034; no cancer n = 2800). Patients with hematological malignancy were younger (median, 61.5 years) with low rates of chronic comorbidities (4.7%) and were usually admitted to ICU from the ward (67.4%). Mechanical ventilation rates were 20.2% and in-hospital mortality was 30.6%. Patients with metastatic solid cancers were older (median, 66.3 years), with higher rates of chronic comorbidities (9.9%), and were usually admitted to the ICU from the emergency department (50.8%). Mechanical ventilation rates were 16.9% and in-hospital mortality was 42.4%. Patients with no documented cancer had highest rates of mechanical ventilation (41.7%) and mortality (46.3%). Neutropenia was independently associated with mortality among patients with solid cancers or no cancer but did not confer increased risk among patients with hematological malignancy (odds ratio, 0.98; 95% confidence interval, .90-1.06; P = .60). Patients with neutropenic sepsis and hematological malignancy, metastatic solid cancer, or no cancer diagnosis constitute 3 distinct clinical groups. Management approaches should be tailored accordingly.

Abstract PO4-16-05: Identification of functional HLA-A*11:01-restricted driver gene PIK3CA mutation specific T-cell receptors

Abstract The adoptive transfer of genetically engineered T-cell receptors (TCR-T) has emerged as a promising therapeutic strategy for the treatment of solid tumors. Recent clinical trials have demonstrated the safety and efficacy of TCR-T cell therapies against certain types of metastatic solid cancers. In our study, we aimed to investigate the potential of TCR-T cell therapies targeting neoantigens, which are exclusively expressed in cancer cells, with a focus on metastatic breast cancer (MBC). Specifically, we identified four driver missense mutations (PIK3CA E542K, E545K, H1047L, and H1047R) frequently observed in MBC patients and utilized computational tools to predict the generation of neoantigens. Utilizing NetMHCpan V.4.1, we performed screening of peptides spanning the mutation region and predicted a neoantigen epitope, PIK3CA_H1047L, to bind with HLA-A*11:01. To validate the presentation and stability of the neoantigen epitope, we employed TAP1-deficient K562 cells and observed stable expression of the mutant peptide-major histocompatibility complex (MHC) complex on the cell membrane. Subsequently, we isolated T cells from healthy donors possessing the HLA-A11:01 genotype, and subjected them to successive stimulations with neopeptide-pulsed dendritic cells. T cells stimulated with neopeptide were examined for neoantigen specificity using an IFN-γ ELISpot assay. Employing pMHC tetramer staining and single-cell sorting via flow cytometry, we successfully isolated five HLA-A11:01-restricted PIK3CA_H1047L-specific TCRs. Through lentivirus transduction of these TCRs into T cells, we achieved the generation of TCR-T cells that exhibited potent and specific activity exclusively against the PIK3CA_H1047L neoantigen. The functionality of the TCR-T cells was confirmed through assessments of CD137 expression, IFN-γ secretion, and cytotoxicity assays. In conclusion, our study demonstrates T cell responses towards neoantigens derived from PIK3CA, a commonly observed driver mutation in MBC. Furthermore, we successfully isolated five distinct neoantigen-specific TCRs that specifically recognized the PIK3CA_H1047L mutation and were restricted to the prevalent HLA-A*11:01 allele. The transfer of these TCRs into T cells resulted in the generation of TCR-T products exhibiting remarkable activity against the PIK3CA_H1047L neoantigen. These findings strongly encourage further investigation into TCRs targeting driver mutations in MBC, with the aim of advancing neoantigen-targeted TCR-T therapies into clinical trials. Additionally, the PIK3CA_H1047L neoantigen holds great promise as a potential candidate for the development of effective cancer vaccines. Citation Format: Meiying Shen, Xiaojian Han, Siyin Chen, Aishun Jin, Shengchun Liu. Identification of functional HLA-A*11:01-restricted driver gene PIK3CA mutation specific T-cell receptors [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-16-05.

Abstract LB344: A novel approach to limit off-tumor toxicity of CAR-T cells targeting solid cancers

Abstract T cells genetically engineered to express a chimeric antigen receptor (CAR) specific for the molecule CD19 have achieved significant gains in the treatment of chemotherapy-resistant leukemia and lymphoma. Despite evidence of long-lived cures in patients with metastatic solid cancer after receiving tumor-specific T cells, no CAR-T cell treatment is currently approved for use against any solid cancer. A large majority of solid cancers express one of many tumor-associated antigens (TAAs) that are vulnerable to CAR T cell recognition. However, in nearly all cases those same TAAs are present in healthy tissues. Since CAR T cells cannot differentiate between cancer and normal cells, CAR T cell recognition of TAAs on healthy tissues provokes dose-limiting ‘on-target off-tumor’ toxicities at sites of endogenous expression (lung, intestine). Thus, there remains a pressing need to develop strategies to mitigate off-tumor toxicity of CAR T cells. To this end, we develop two immunocompetent models of CAR T cell transfer targeting TAAs abundant in metastatic colorectal cancer and pancreatic cancer. TAA-specific CAR T cells affected tumor shrinkage along with infiltrating and damaging sites of endogenous expression (primarily lung, pancreas, &amp; colon). In both of our models, off-tumor toxicities were antigen-dependent and resulted in tissue damage, systemic inflammation, and host death that was titratable to CAR-T cell dose. TAA-specific CAR T cells infiltrated sites of endogenous expression such as the intestine, pancreas, and lungs. Notably, the respiratory system was the site of greatest pathology in both of our models, with massive CAR T cell accumulation and tissue destruction that resulted in systemic wasting and rapid weight loss. Remarkably, we found that the presence of an antigen-bearing tumor in the liver, but not other sites, greatly exacerbated CAR-T cell pulmonary infiltration, tissue destruction, and host mortality.The liver is the most common site of metastasis in patients with colorectal and pancreatic adenocarcinoma and the only site of metastasis in one-third of colorectal cancers. Our models indicated that TAA-specific CAR-T cells given for the treatment of liver metastasis result in dose-limiting pulmonary toxicity due to the presence of the TAA in the healthy lung. To address this translational barrier, we designed and validated a multiparameter genetic reprogramming targeting T cell trafficking and tissue residency introduced with the CAR to imbue CAR-T cells with liver tropism. In multiple models, CAR T cells programmed with liver-specific tropism augmented CAR T cell liver trafficking, decreased lung infiltration and toxicity, and effectively treated TAA+ liver metastasis. We aim to initiate a pilot clinical trial using tissue resident-programmed CAR T cells to treat colorectal liver metastasis. Citation Format: Alex Bartlett, Matthew Mcwhorter, Camille Collier, Chelsea Jenkins, Robert Eil. A novel approach to limit off-tumor toxicity of CAR-T cells targeting solid cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB344.

Abstract 117: Improved PBMC humanized mouse models for immuno-oncology drugs evaluation

Abstract It has been demonstrated that anti-PD(L)1 therapy could significantly improve survival outcomes for patients with metastatic solid cancers, such as melanoma, non-small cell lung cancer and MSI-H colorectal cancer. However, more than half of these patients (NCT02563002, NCT02142738, NCT02563002) do not respond to immune checkpoint blockade (ICB) therapy, and 90% of colorectal cancer patients have MSS/pMMR characteristics and almost no response at all, which drives scientists to design novel drug candidates urgently and integrate tumor and tumor microenvironment (TME) signals systemically to rejuvenate exhausted immune system and overcome ICB resistance. LIDE has developed both traditional PBMC humanized mice model, and human immune cells and cancer co-inoculated model for IO drugs functional evaluation in the last 5-years by using unique PBMC donor selection and standard cancer biobank (PDX patient-derived xenografts, CDX cell derived xenograft) establishment. Cancer biopsies with MDM2 amplification or DNMT3A alternation have been shown resistant to PD1-Ab therapy but sensitive to chemical combo-therapy, and pMMR cancer PDX models seem responsible well to EGFR targeted, CD39-CD73-Adenosine targeted therapy. Human IL15 transgenic mice are used as one useful tool to investigate in vivo function of NK cells, NK engagers/modulators as well as drugs with ADCC (Antibody dependent cell-mediated cytotoxicity) effect. The activated immune cells and cancer co-transfer model, can significantly delay the graft-versus-host-reaction for another month compared with traditional PBMC humanized model, and archives maximal therapeutic effect of the testing drugs by pre-activating T cells with specific tumor antigens. Dendritic cells or macrophages could be successfully introduced into this co-inoculated system to work together with T cells, mimic human tumor tissue complexity, to help determine the overall effect induced by integrated signals. It seems CD40 agonist or CD47 antagonist could well synergies with anti-PD(L)1 to control melanoma and triple negative breast cancer development, respectively. This optimized PBMC humanized cancer-bearing mice models have been tested for various cancer targets, e.g. PD(L)1, Tim3, Lag3, Tigit, PVRIG, TGFβ1, CD73/CD39, CD47/Sirpa, DLL3/CD3, Claudin18.2/4-1BB, B7-H3, GITR, to better understand the interaction between cancer cells and immune cells. Citation Format: Bin Xie, Xin Hou, Pengfei Yang, Yanbing Zhou, Danyi Wen. Improved PBMC humanized mouse models for immuno-oncology drugs evaluation [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 117.

Abstract 3595: A retrospective analysis of the clinical characteristics of metastastic solid cancer patients with cytokine-induced killer cells combined immune checkpoint inhibitor immunotherapy

Abstract Background: Cytokine-induced killer cells (CIKs), obtained through ex vivo expasion from peripheral blood mononuclear cells, are phenotypically and functionally shared with both T and NK cells. Within the T cell group, it can be classified into a group that simultaneously expresses CD3 and CD56 molecules (range: 30% to 70%) and a group representing CD3+ CD56- phenotype (range: 20% to 60%). It also contains a small population (&amp;lt; 30%) of CD3 CD56+ NK cells. They can exhibit potent MHC-unrestricted cytotoxicity for both hematologic and solid tumors, but they are not harmful in hematopoietic precursors and normal tissues. Anti-programmed death-1 (PD-1) antibodies reinvigorate T cell-mediated antitumor immunity. PD-1 blockade antibody might significantly increase the cytotoxic potency of CIK cells via increasing proliferative capacity and IFN-r secretion. This retrospective study is the first to combine CIK cells with PD-1/PD-L1/CTLA-4 blockade(Immune checkpoint inhibitors, ICIs) in patients with metastatic solid cancers. Methods: We analyzed 225 heavily treated metastastic solid cancer patients receiving CIK cell (Immunecell-LC, GC cell inc provide.) and with ICIs. Blood Sampling for CIK cells production was performed after 3 days after ICIs administration. Patients received a single intravenous infusion of activated autologous CIK cells every 2 weeks. ICIs was administered according to the protocol of each drug regardless of the CIK cells administration date. The primary end points were safety and adverse event (AE) profiles. Objective responses, overall survival (OS), progression-free survival (PFS), and diseae control rate were secondary end points. Results: Treatment-related AEs occurred in 154/225 patients. Grade 3 or 4 toxicities, including fever and chills, were observed in 28 patients. All treatment-related AEs were tolerable and no death due to autoimmune disease. When administration ICIs, CIK cells exhibited excellent antitumor properties and increased IFN-γ secretion. Objective responses (complete or partial responses) were observed in 67 of the 225 patients. One patients with hepatocellular carcionma had complete response. In most patients who showed an objective response, the effectiveness was maintained for more than 6 months. The overall disease control rate in the patients was 58.9%. At the time of this report, the median OS and PFS were 18.6 and 7.1 months in hepatocellular carcinoma patients and were 13.1 and 6.5 months in triple negative breast cancer patients, respectively. Conclusion: Treatment with activated autologous CIK cells and ICIs was safe and exerted encouraging antitumor activity in metastastic solid cancers. Phase 2 clinical studies for each tumor type will be conducted. Keywords: Cytokine-induced killer cells, Immune check inhibitors, Safety, Objective response Citation Format: Jonggwon Choi, Jong Yeup Kim, Dong Won Yang, Gun He Nam. A retrospective analysis of the clinical characteristics of metastastic solid cancer patients with cytokine-induced killer cells combined immune checkpoint inhibitor immunotherapy [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 3595.

Phase II study of nivolumab in patients with genetic alterations in DNA damage repair and response who progressed after standard treatment for metastatic solid cancers (KM-06)

BackgroundImmune-modulating antibodies targeting programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) have demonstrated promising antitumor efficacy in various types of cancers, especially highly mutated ones. Genetic alterations in DNA damage...