An in-depth understanding of immune escape mechanisms in cancer is likely to lead to innovative advances in immunotherapeutic strategies. However, much remains unknown regarding these mechanisms and ...how they impact immunotherapy resistance. Using several preclinical tumor models as well as clinical specimens, we identified a mechanism whereby CD8+ T cell activation in response to programmed cell death 1 (PD-1) blockade induced a programmed death ligand 1/NOD-, LRR-, and pyrin domain-containing protein 3 (PD-L1/NLRP3) inflammasome signaling cascade that ultimately led to the recruitment of granulocytic myeloid-derived suppressor cells (PMN-MDSCs) into tumor tissues, thereby dampening the resulting antitumor immune response. The genetic and pharmacologic inhibition of NLRP3 suppressed PMN-MDSC tumor infiltration and significantly augmented the efficacy of anti-PD-1 antibody immunotherapy. This pathway therefore represents a tumor-intrinsic mechanism of adaptive resistance to anti-PD-1 checkpoint inhibitor immunotherapy and is a promising target for future translational research.
Preclinical studies suggest PARP inhibition (PARPi) induces immunostimulatory micromilieu in ovarian cancer thus complementing activity of immune checkpoint blockade. We conducted a phase II trial of ...PARPi olaparib and anti-PD-L1 durvalumab and collected paired fresh core biopsies and blood samples to test this hypothesis.
In a single-center, proof-of-concept phase II study, we enrolled women aged ≥18 with recurrent ovarian cancer. All patients were immune checkpoint inhibitor-naïve and had measurable disease per RECISTv1.1, ECOG performance status 0-2, and adequate organ and marrow function. Patients received olaparib 300 mg twice daily and durvalumab 1,500 mg intravenously every 4 weeks until disease progression, unacceptable toxicity, or withdrawal of consent. Primary endpoint was overall response rate (ORR). Secondary objectives were safety and progression-free survival (PFS). Translational objectives included biomarker evaluation for relationships with clinical response and immunomodulatory effects by treatment.
Thirty-five patients with ovarian cancer median, four prior therapies (IQR, 2-5.5), predominantly platinum-resistant (86%),
wild-type (77%) received at least one full cycle of treatment. ORR was 14% 5/35; 95% confidence interval (CI), 4.8%-30.3%. Disease control rate (PR+SD) was 71% (25/35; 95% CI, 53.7%-85.4%). Treatment enhanced
and
expression, systemic IFNγ/TNFα production, and tumor-infiltrating lymphocytes, indicating an immunostimulatory environment. Increased IFNγ production was associated with improved PFS HR, 0.37 (95% CI, 0.16-0.87),
= 0.023, while elevated VEGFR3 levels were associated with worse PFS (HR, 3.22 (95% CI, 1.23-8.40),
= 0.017.
The PARPi and anti-PD-L1 combination showed modest clinical activity in recurrent ovarian cancer. Our correlative study results suggest immunomodulatory effects by olaparib/durvalumab in patients and indicate that VEGF/VEGFR pathway blockade would be necessary for improved efficacy of the combination.
Background
Regorafenib is an oral multikinase inhibitor targeting angiogenesis, oncogenesis, and cancer proliferation/metastasis. This study evaluated the efficacy of regorafenib in refractory ...biliary tract cancer (BTC) in a multi‐institutional phase 2 study.
Methods
Patients with BTC who progressed on at least 1 line of systemic therapy received regorafenib at 160 mg daily for 21 days on and 7 days off. The primary endpoint was 6‐month overall survival (OS), and the secondary endpoints were median OS, progression‐free survival (PFS), and objective response rates. Pretreatment plasma was collected for cytokine evaluation.
Results
A total of 39 patients were enrolled, and 33 were evaluable for efficacy. The median PFS and OS were 3.7 and 5.4 months, respectively, with survival rates of 46.2% at 6 months, 35.9% at 12 months, and 25.6% at 18 months for the intention‐to‐treat population. For the 33 evaluable patients who received regorafenib for at least 3 weeks, the median PFS and OS were 3.9 and 6.7 months, respectively, with survival rates of 51.5% at 6 months, 39.4% at 12 months, and 27.3% at 18 months. The objective response rate was 9.1%, and the disease control rate was 63.6%. Twenty‐eight patients (71.8%) experienced grade 3/4 adverse events. Among the 23 cytokines analyzed, elevated baseline vascular endothelial growth factor D (VEGF‐D) was associated with shorter PFS, whereas elevated baseline interleukin 6 (IL‐6) and glycoprotein 130 (GP130) were associated with shorter OS.
Conclusions
Regorafenib demonstrated modest clinical efficacy in heavily pretreated patients with BTC. Further exploration of biomarkers is warranted to identify a group of patients with BTC who may benefit from regorafenib.
Regorafenib can provide modest clinical efficacy and a manageable safety profile in heavily pretreated patients with advanced biliary tract cancer.
Drugs and antibodies that interrupt vascular endothelial growth factor (VEGF) signaling pathways improve outcomes in patients with a variety of cancers by inhibiting tumor angiogenesis. A major ...adverse effect of these treatments is hypertension, suggesting a critical role for VEGF in blood pressure (BP) regulation. However, the physiological mechanisms underlying the control of BP by VEGF are unclear. To address this question, we administered a specific antibody against the major VEGF receptor, VEGFR2, to normal mice and assessed the consequences on BP. Compared with vehicle-treated controls, administration of the anti-VEGFR2 antibody caused a rapid and sustained increase in BP of approximately 10 mm Hg. This increase in BP was associated with a significant reduction in renin mRNA expression in the kidney (P=0.019) and in urinary excretion of aldosterone (P<0.05). Treatment with the anti-VEGFR2 antibody also caused a marked reduction in the expression of endothelial and neuronal NO synthases in the kidney. To examine the role of NO in the hypertension caused by blocking VEGFR2, mice were treated with N(omega)-nitro-L-arginine methyl ester (L-NAME) (20 mg/kg per day), an inhibitor of NO production. L-NAME administration abolished the difference in BP between the vehicle- and anti-VEGFR2-treated groups. Our data suggest that VEGF, acting via VEGFR2, plays a critical role in BP control by promoting NO synthase expression and NO activity. Interfering with this pathway is likely to be one mechanism underlying hypertension caused by antiangiogenic agents targeting VEGF.
The immunologic landscape of the host and tumor play key roles in determining how patients will benefit from immunotherapy, and a better understanding of these factors could help inform how well a ...tumor responds to treatment. Recent advances in immunotherapy and in our understanding of the immune system have revolutionized the treatment landscape for many advanced cancers. Notably, the use of immune checkpoint inhibitors has demonstrated durable responses in various malignancies. However, the response to such treatments is variable and currently unpredictable, the availability of predictive biomarkers is limited, and a substantial proportion of patients do not respond to immune checkpoint therapy. Identification and investigation of potential biomarkers that may predict sensitivity to immunotherapy is an area of active research. It is envisaged that a deeper understanding of immunity will aid in harnessing the full potential of immunotherapy, and allow appropriate patients to receive the most appropriate treatments. In addition to the identification of new biomarkers, the platforms and assays required to accurately and reproducibly measure biomarkers play a key role in ensuring consistency of measurement both within and between patients. In this review we discuss the current knowledge in the area of peripheral immune-based biomarkers, drawing information from the results of recent clinical studies of a number of different immunotherapy modalities in the treatment of cancer, including checkpoint inhibitors, bispecific antibodies, chimeric antigen receptor T cells, and anti-cancer vaccines. We also discuss the various technologies and approaches used in detecting and measuring circulatory biomarkers and the ongoing need for harmonization.
Approximately 30 years ago, endoglin was identified as a transforming growth factor (TGF)-β coreceptor with a crucial role in developmental biology and tumor angiogenesis. Its selectively high ...expression on tumor vessels and its correlation with poor survival in cancer patients led to the exploration of endoglin as a therapeutic target for cancer. The endoglin neutralizing antibody TRC105 (Carotuximab
, Tracon Pharmaceuticals (San Diego, CA, USA) was subsequently tested in a wide variety of preclinical cancer models before being tested in phase I-III clinical studies in cancer patients as both a monotherapy and in combination with other chemotherapeutic and anti-angiogenic therapies. The combined data of these studies have revealed new insights into the role of endoglin in angiogenesis and its expression and functional role on other cells in the tumor microenvironment. In this review, we will summarize the preclinical work, clinical trials and biomarker studies of TRC105 and explore what these studies have enabled us to learn and what questions remain unanswered.
Formalin-fixed, paraffin-embedded tumor samples from CALGB 80203 were analyzed for expression of EGFR axis-related genes to identify prognostic or predictive biomarkers for cetuximab treatment.
...Patients (238 total) with first-line metastatic colorectal cancer (mCRC) were randomized to FOLFOX or FOLFIRI chemotherapy ± cetuximab. qRT-PCR analyses were conducted on tissues from 103 patients at baseline to measure gene expression levels of HER-related genes, including amphiregulin (AREG), betacellulin (BTC), NT5E (CD73), DUSP4, EGF, EGFR, epigen (EPGN), epiregulin (EREG), HBEGF, ERBB2 (HER2), ERBB3 (HER3), ERBB4 (HER4), PHLDA1, and TGFA. The interactions between expression levels and treatment with respect to progression-free survival (PFS) and overall survival (OS) were modeled using multiplicative Cox proportional hazards models.
High tumor mRNA levels of HER2 hazard ratio (HR), 0.64; P = 0.002 and EREG (HR, 0.89; P = 0.016) were prognostic markers associated with longer PFS across all patients. HER3 and CD73 expression levels were identified as potential predictive markers of benefit from cetuximab. In KRAS wild-type (WT) tumors, low HER3 expression was associated with longer OS from cetuximab treatment, whereas high HER3 expression was associated with shorter OS from cetuximab treatment (chemo + cetuximab: HR, 1.15; chemo-only: HR, 0.48; Pinteraction = 0.029). High CD73 expression was associated with longer PFS from cetuximab treatment in patients with KRAS-WT (chemo + cetuximab: HR, 0.91; chemo-only: HR, 1.57; Pinteraction = 0.026) and KRAS-mutant (Mut) tumors (chemo + cetuximab: HR, 0.80; chemo-only: HR, 1.29; P = 0.025).
Gene expression of HER3 and CD73 was identified as a potential predictive marker for cetuximab. These data implicate HER axis signaling and immune modulation as potential mechanisms of cetuximab action and sensitivity.
Abstract
Background
The incidence of young-onset colorectal cancer (yoCRC) is increasing. It is unknown if there are survival differences between young and older patients with metastatic colorectal ...cancer (mCRC).
Methods
We studied the association of age with survival in 2326 mCRC patients enrolled in the Cancer and Leukemia Group B and SWOG 80405 trial, a multicenter, randomized trial of first-line chemotherapy plus biologics. The primary and secondary outcomes of this study were overall survival (OS) and progression-free survival (PFS), respectively, which were assessed by Kaplan-Meier method and compared among younger vs older patients with the log-rank test. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated based on Cox proportional hazards modeling, adjusting for known prognostic variables. All statistical tests were 2-sided.
Results
Of 2326 eligible subjects, 514 (22.1%) were younger than age 50 years at study entry (yoCRC cohort). The median age of yoCRC patients was 44.3 vs 62.5 years in patients aged 50 years and older. There was no statistically significant difference in OS between yoCRC vs older-onset patients (median = 27.07 vs 26.12 months; adjusted HR = 0.98, 95% CI = 0.88 to 1.10; P = .78). The median PFS was also similar in yoCRC vs older patients (10.87 vs 10.55 months) with an adjusted hazard ratio of 1.02 (95% CI = 0.92 to 1.13; P = .67). Patients younger than age 35 years had the shortest OS with median OS of 21.95 vs 26.12 months in older-onset patients with an adjusted hazard ratio of 1.08 (95% CI = 0.81 to 1.44; Ptrend = .93).
Conclusion
In this large study of mCRC patients, there were no statistically significant differences in survival between patients with yoCRC and CRC patients aged 50 years and older.
Growth factors in tumor environments are regulators of cell survival and metastasis. Here, we reveal the dichotomy between TGF-β superfamily growth factors BMP and TGF-β/activin and their downstream ...SMAD effectors. Gene expression profiling uncovers SOX2 as a key contextual signaling node regulated in an opposing manner by BMP2, -4, and -9 and TGF-β and activin A to impact anchorage-independent cell survival. We find that SOX2 is repressed by BMPs, leading to a reduction in intraperitoneal tumor burden and improved survival of tumor-bearing mice. Repression of SOX2 is driven by SMAD1-dependent histone H3K27me3 recruitment and DNA methylation at SOX2’s promoter. Conversely, TGF-β, which is elevated in patient ascites, and activin A can promote SOX2 expression and anchorage-independent survival by SMAD3-dependent histone H3K4me3 recruitment. Our findings identify SOX2 as a contextual and contrastingly regulated node downstream of TGF-β members controlling anchorage-independent survival and metastasis in ovarian cancers.
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•SOX2 is a key node for anchorage-independent survival in cancer•SOX2 levels are differentially balanced by TGF-β/activin and BMPs in cancer•BMP9 is a robust intraperitoneal metastasis suppressor by lowering SOX2•SOX2 regulation is contextual and at the transcriptional level
Tumor cell survival upon loss of attachment is critical for metastasis. Shonibare et al. identify SOX2 as a contextual node regulated contrastingly by BMPs and TGF-β. Regulation occurs via distinct SMAD1- and SMAD3-dependent histone recruitment and DNA methylation mechanisms influencing anchorage-independent cell survival and intraperitoneal ovarian cancer metastasis.
Herein, we report results from a genome-wide study conducted to identify protein quantitative trait loci (pQTL) for circulating angiogenic and inflammatory protein markers in patients with metastatic ...colorectal cancer (mCRC). The study was conducted using genotype, protein marker, and baseline clinical and demographic data from CALGB/SWOG 80405 (Alliance), a randomized phase III study designed to assess outcomes of adding VEGF or EGFR inhibitors to systemic chemotherapy in mCRC patients. Germline DNA derived from blood was genotyped on whole-genome array platforms. The abundance of protein markers was quantified using a multiplex enzyme-linked immunosorbent assay from plasma derived from peripheral venous blood collected at baseline. A robust rank-based method was used to assess the statistical significance of each variant and protein pair against a strict genome-wide level. A given pQTL was tested for validation in two external datasets of prostate (CALGB 90401) and pancreatic cancer (CALGB 80303) patients. Bioinformatics analyses were conducted to further establish biological bases for these findings.
The final analysis was carried out based on data from 540,021 common typed genetic variants and 23 protein markers from 869 genetically estimated European patients with mCRC. Correcting for multiple testing, the analysis discovered a novel cis-pQTL in LINC02869, a long non-coding RNA gene, for circulating TGF-β2 levels (rs11118119; AAF = 0.11; P-value < 1.4e-14). This finding was validated in a cohort of 538 prostate cancer patients from CALGB 90401 (AAF = 0.10, P-value < 3.3e-25). The analysis also validated a cis-pQTL we had previously reported for VEGF-A in advanced pancreatic cancer, and additionally identified trans-pQTLs for VEGF-R3, and cis-pQTLs for CD73.
This study has provided evidence of a novel cis germline genetic variant that regulates circulating TGF-β2 levels in plasma of patients with advanced mCRC and prostate cancer. Moreover, the validation of previously identified pQTLs for VEGF-A, CD73, and VEGF-R3, potentiates the validity of these associations.
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