Targeting developmental pathways: the Achilles Heel of cancer?

Developmental pathways (e.g., Notch, Hippo, Hedgehog, Wnt, and TGF-β/BMP/FGF) are networks of genes that act co-ordinately to establish the body plan, and disruptions of genes in one pathway can have effects in related pathways and may result in serious dysmorphogenesis or cancer. Interestingly, all developmental pathways are highly conserved cell signalling systems present in almost all multicellular organisms. In addition, they have a crucial role in cell proliferation, apoptosis, differentiation, and finally in organ development. Of note, almost all of these pathways promote oncogenesis through synergistic associations with the Hippo signalling pathway, and several lines of evidence have also indicated that these pathways (e.g., Wnt/β-catenin) may be implicated in checkpoint inhibitor resistance (e.g., CTLA-4, PD-1, and PD-L1). Since Notch inhibition in vivo results in partial loss of its stemness features such as self-renewal, chemoresistance, invasive and migratory potential, and tumorigenesis, these highly conserved developmental pathways are regarded as being critical for regulation of self-renewal in both embryonic and adult stem cells and hence are likely to be implicated in the maintenance of cancer stem cells. Many small molecules are currently in preclinical and early clinical development, and only two compounds are approved for treatment of advanced or metastatic basal cell carcinoma (vismodegib and sonidegib). Furthermore, therapeutic targeting of cancer stem cells using drugs that disrupt activated developmental pathways may also represent an attractive strategy that is potentially relevant to many types of malignancy, notably blood cancers, where the evidence for leukaemia stem cells is well established. Future work will hopefully pave the way for the development of new strategies for targeting these pervasive oncogenic pathways

Efficacy and Safety of Approved First-Line Tyrosine Kinase Inhibitor Treatments in Metastatic Renal Cell Carcinoma: A Network Meta-Analysis

Introduction This network meta-analysis aims to deliver an up-to-date, comprehensive efficacy and toxicity comparison of the approved first-line tyrosine kinase inhibitors (TKIs) for metastatic renal cell carcinoma (mRCC) in order to provide support for evidence-based treatment decisions. Previous NMAs of first-line mRCC treatments either predate the approval of all the first-line TKIs currently available or do not include evaluation of safety data for all treatments. Methods We performed a systematic literature review and network meta-analysis of phase II/III randomised controlled trials (RCTs) assessing approved first-line TKI therapies for mRCC. A random effects model with a frequentist approach was computed for progression-free survival (PFS) data and for the proportion of patients experiencing a maximum of grade 3 or 4 adverse events (AEs). Results The network meta-analysis of PFS demonstrated no significant differences between cabozantinib and either sunitinib (50 mg 4/2), pazopanib or tivozanib. The network meta-analysis indicated that in terms of grade 3 and 4 AEs, tivozanib had the most favourable safety profile and was associated with significantly less risk of toxicity than the other TKIs. Conclusion These network meta-analysis data demonstrate that cabozantinib, sunitinib, pazopanib and tivozanib do not significantly differ in their efficacy, but tivozanib is associated with a more favourable safety profile in terms of grade 3 or 4 toxicities. Consequently, the relative toxicity of these first-line TKIs may play a more significant role than efficacy comparisons in treatment decisions and in planning future RCTs

Retrospective Analysis of Treatment Pathways in Patients With BRAFV600E-mutant Metastatic Colorectal Carcinoma - MORSECRC.

BACKGROUND/AIM Metastatic colorectal cancer (mCRC) is a heterogeneous disease with distinct molecular subtypes. The BRAFV600E-mutation found in approximately 8-12% of mCRC patients is associated with poor prognosis. Guideline recommendations for this population are mostly based on small cohorts due to lack of clinical data. This retrospective analysis was designed to evaluate (approved) therapeutic approaches and algorithms in BRAFV600E-mutant mCRC prior to approval of the targeted combination encorafenib plus cetuximab in Germany, Austria, and Switzerland. PATIENTS AND METHODS Anonymized data from BRAFV600E-mutant mCRC patients were analyzed retrospectively regarding 1st-, 2nd- and 3rd-line treatment using descriptive statistics. RESULTS Forty-two patients were eligible for analysis (mean age 62.1 years, 47.6% female). At initial diagnosis, 20 patients (47.6%) were documented with right-sided tumors. Most patients (81.0%) were tested for BRAF before 1st-line. Four patients (9.5%) showed high microsatellite instability (MSI-H). Based on 94 treatment lines, chemotherapy combined with targeted therapy (TT) was used mostly (61.7%), followed by chemotherapy alone (19.1%). Backbone therapies were most frequently FOLFOXIRI (27.7%), FOLFOX/CAPOX (22.3%), or FOLFIRI (20.2%). Anti-VEGF/VEGFR and anti-EGFR-treatments were used in 45.7% and 23.4% of patients, respectively. Across all treatment lines and types, the predominantly documented reason for discontinuation was lack of efficacy. CONCLUSION Combined chemotherapy+TT (anti-VEGF/VEGFR and anti-EGFR) played a predominant role in BRAFV600E-mutated mCRC treatment prior to approval of the targeted combination encorafenib plus cetuximab. Since lack of efficacy was the major reason for treatment discontinuation, newly approved therapies including encorafenib plus cetuximab and - for MSI-H tumors - pembrolizumab represent urgently needed options for future mCRC patients

Inorganic carbon acquisition in red-tide dinoflagellates

Carbon acquisition was investigated in three marine bloom-forming dinoflagellates – Prorocentrum minimum, Heterocapsa triquetra and Ceratium lineatum. In vivo activities of extracellular and intracellular carbonic anhydrase (CA), photosynthetic O2 evolution, CO2 and HCO3– uptake rates were measured by membrane inlet mass spectrometry (MIMS) in cells acclimated to low pH (8.0) and high pH (8.5 or 9.1). A second approach used short-term 14C-disequilibrium incubations to estimate the carbon source utilized by the cells. All three species showed negligible extracellular CA (eCA) activity in cells acclimated to low pH and only slightly higher activity when acclimated to high pH. Intracellular CA (iCA) activity was present in all three species, but it increased only in P. minimum with increasing pH. Half-saturation concentrations (K1/2) for photosynthetic O2 evolution were low compared to ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) kinetics. Moreover, apparent affinities for inorganic carbon (Ci) increased with increasing pH in the acclimation, indicating the operation of an efficient CO2 concentration mechanism (CCM) in these dinoflagellates. Rates of CO2 uptake were comparably low and could not support the observed rates of photosynthesis. Consequently, rates of HCO3– uptake were high in the investigated species, contributing more than 80% of the photosynthetic carbon fixation. The affinity for HCO3– and maximum uptake rates increased under higher pH. The strong preference for HCO3– was also confirmed by the 14C-disequilibrium technique. Modes of carbon acquisition were consistent with the 13C-fractionation pattern observed and indicated a strong species-specific difference in leakage. These results suggest that photosynthesis in marine dinoflagellates is not limited by Ci even at high pH, which may occur during red tides in coastal waters

Use of immunoglobulin replacement therapy in patients with secondary antibody deficiency in daily practice: a European expert Q&A-based review

Introduction: Secondary antibody deficiencies (SAD) are often a side effect of specific therapies that target B cells directly or affect the antibody response indirectly. Treatment of immunodeficiency by immunoglobulin replacement therapy (IgRT) is well established in primary antibody deficiencies, although the evidence for its use in SAD is less well established. To fill the gap and provide opinion and advice for daily practice, a group of experts met to discuss current issues and share best practical experience. Areas covered: A total of 16 questions were considered that covered use of a tailored approach, definition of severe infections, measurement of IgG levels and specific antibodies, indications for IgRT, dosage, monitoring, discontinuation of IgRT, and Covid-19. Expert opinion: Key points for better management SID should include characterization of the immunological deficiency, determination of the severity and degree of impairment of antibody production, distinguish between primary and secondary deficiency, and design a tailored treatment protocol that should include dose, route, and frequency of Ig replacement. There remains the need to carry out well-designed clinical studies to develop clear guidelines for the use of IgRT in patients with SAD

Lorlatinib in pretreated ALK- or ROS1-positive lung cancer and impact of TP53 co-mutations: results from the German early access program

Introduction: We report on the results of the German early access program (EAP) with the third-generation ALK- and ROS1-inhibitor lorlatinib. Patients and Methods: Patients with documented treatment failure of all approved ALK/ROS1-specific therapies or with resistance mutations not covered by approved inhibitors or leptomeningeal carcinomatosis were enrolled and analyzed. Results: In total, 52 patients were included [median age 57 years (range 32-81), 54% female, 62% never smokers, 98% adenocarcinoma]; 71% and 29% were ALK- and ROS1-positive, respectively. G1202R and G2032R resistance mutations prior to treatment with lorlatinib were observed in 10 of 26 evaluable patients (39%), 11 of 39 patients showed TP53 mutations (28%). Thirty-six patients (69%) had active brain metastases (BM) and nine (17%) leptomeningeal carcinomatosis when entering the EAP. Median number of prior specific TKIs was 3 (range 1-4). Median duration of treatment, progression-free survival (PFS), response rate and time to treatment failure were 10.4 months, 8.0 months, 54% and 13.0 months. Calculated 12-, 18- and 24-months survival rates were 65, 54 and 47%, overall survival since primary diagnosis (OS2) reached 79.6 months. TP53 mutations were associated with a substantially reduced PFS (3.7 versus 10.8 month, HR 3.3, p = 0.003) and were also identified as a strong prognostic biomarker (HR for OS2 3.0 p = 0.02). Neither prior treatments with second-generation TKIs nor BM had a significant influence on PFS and OS. Conclusions: Our data from real-life practice demonstrate the efficacy of lorlatinib in mostly heavily pretreated patients, providing a clinically meaningful option for patients with resistance mutations not covered by other targeted therapies and those with BM or leptomeningeal carcinomatosis

Lorlatinib in pretreated ALK- or ROS1-positive lung cancer and impact of TP53 co-mutations: results from the German early access program

Introduction: We report on the results of the German early access program (EAP) with the third-generation ALK- and ROS1-inhibitor lorlatinib. Patients and Methods: Patients with documented treatment failure of all approved ALK/ROS1-specific therapies or with resistance mutations not covered by approved inhibitors or leptomeningeal carcinomatosis were enrolled and analyzed. Results: In total, 52 patients were included [median age 57 years (range 32-81), 54% female, 62% never smokers, 98% adenocarcinoma]; 71% and 29% were ALK- and ROS1-positive, respectively. G1202R and G2032R resistance mutations prior to treatment with lorlatinib were observed in 10 of 26 evaluable patients (39%), 11 of 39 patients showed TP53 mutations (28%). Thirty-six patients (69%) had active brain metastases (BM) and nine (17%) leptomeningeal carcinomatosis when entering the EAP. Median number of prior specific TKIs was 3 (range 1-4). Median duration of treatment, progression-free survival (PFS), response rate and time to treatment failure were 10.4 months, 8.0 months, 54% and 13.0 months. Calculated 12-, 18- and 24-months survival rates were 65, 54 and 47%, overall survival since primary diagnosis (OS2) reached 79.6 months. TP53 mutations were associated with a substantially reduced PFS (3.7 versus 10.8 month, HR 3.3, p = 0.003) and were also identified as a strong prognostic biomarker (HR for OS2 3.0 p = 0.02). Neither prior treatments with second-generation TKIs nor BM had a significant influence on PFS and OS. Conclusions: Our data from real-life practice demonstrate the efficacy of lorlatinib in mostly heavily pretreated patients, providing a clinically meaningful option for patients with resistance mutations not covered by other targeted therapies and those with BM or leptomeningeal carcinomatosis