SHP2 Inhibitor Research Articles

Waking immune-resistant tumors with neddylation.

The CD47/signal regulatory protein α (SIRPα) axis, which functions as an inhibitory phagocytosis checkpoint, also serves as a key mediator in cancer immune evasion. Many cancers, including colorectal cancer (CRC), exploit the expression of CD47 to escape phagocytic clearance and activate the innate immune system. Previous work has indicated that distinct paradigms of posttranslational modifications mediate the regulatory mechanisms of the CD47/SIRPα axis. In this issue of the JCI, Li et al. show that neddylation, a ubiquitin-like modification, inactivates Src homology region 2-containing protein tyrosine phosphatase 2 (SHP2), a downstream target of this pathway. They further show that inhibition of SHP2 sensitizes CRC cells to immunotherapies to which they were previously resistant. Collectively, the results underscore the need for cotargeting SHP2 and immune checkpoints (e.g., programmed death 1 [PD1]) in CRC and possibly other immunotherapy-resistant tumors.

Targeting SHP2 reverses BRAF inhibitor tolerance in anaplastic thyroid carcinoma.

To explore the possibility of a combination of dabrafenib and SHP2 inhibitor in the treatment of anaplastic thyroid carcinoma and to provide a new therapeutic strategy for the treatment of anaplastic thyroid cancer. Firstly, a drug resistance model was established, and the expression levels of related RTK were detected by qPCR. Western blot was used to detect the protein expression levels of Akt and MAPK signaling pathways in the control group, single-drug group and two-drug combination group. The gene silencing of SHP2 was achieved by transfection of siRNA and verified by Western blot. CCK8 kit and clone formation assay were used to detect cell proliferation activity. In vivo model of mutant thyroid cancer cells was established by subcutaneous injection of mice and then divided into four groups. Tumor diameter was measured every two days. Immunohistochemistry was used to evaluate the expression of p-ERK, p-AKT and Ki67 in mouse tumors. In this study, dabrafenib-resistant ATC cells were first constructed, and the response of RTKs in drug-resistant cells was upregulated to activate Akt and MER/ERK pathways. The activation of Akt and MEK/ERK pathways in the combination group was significantly inhibited, and the proliferation ability of tumor cells was significantly reduced compared with Dabrafenib, SHP099 group and DMSO group. To verify that SHP099 was not off-target, we also silenced SHP2 expression by transfection with siRNA and obtained the same results. Finally, by building a mouse drug resistance model, we confirmed that dabrafenib and SHP099 can also play a powerful anti-cancer effect in vivo. The SHP2 inhibitor SHP099 can effectively reverse the drug resistance of dabrafenib through inhibiting the reactivated RAS signaling pathway in anaplastic thyroid cancer.The combination of dabrafenib with SHP2 inhibitor has shown significant tumor suppressive effects for dabrafenib-resistant cells and it may be a new therapeutic strategy with longer lasting therapeutic benefits.

Efficacious Combination Drug Treatment for Colorectal Cancer That Overcomes Resistance to KRAS G12C Inhibitors.

Recent advances in combinatorial chemistry led to the discovery of inhibitors targeting the KRAS G12C-mutant protein. However, efficacy of its monotherapy on colorectal cancer is limited. Thus, effective combination drugs should be explored for applicable patients with colorectal cancer to fully benefit from the KRAS G12C inhibitor treatment. Here we used a patient-derived colorectal cancer stem cell (PD-CRC-SC) spheroid culture and showed that three-drug combination of inhibitors against KRAS G12C, EGFR, and FGFR synergistically suppressed the growth of colorectal cancer cells carrying the KRAS G12C mutation. Likewise, a combination of KRAS G12C and SHP2 inhibitors was also effective. Importantly, activation of the PI3K/AKT pathway in heregulin-responsive colorectal cancer cells canceled out the effect of KRAS G12C inhibition, which was largely overcome by PI3K inhibitors. These results reveal that evaluating efficacy of combination therapies with PD-CRC-SC spheroids can be a promising strategy to find the best regimen for patients with colorectal cancer.

Identification of linderalactone as a natural inhibitor of SHP2 to ameliorate CCl4-induced liver fibrosis.

Liver fibrosis is characterised by the activation of hepatic stellate cells (HSCs) and matrix deposition. Accumulating evidence has revealed that the oncogenic protein tyrosine phosphatase Src homology 2 domain-containing phosphatase 2 (SHP2) acts as a therapeutic target of fibrosis. Although several SHP2 inhibitors have reached early clinical trials, there are currently no FDA-approved drugs that target SHP2. In this study, we aimed to identify novel SHP2 inhibitors from an in-house natural product library to treat liver fibrosis. Out of the screened 800 compounds, a furanogermacrane sesquiterpene, linderalactone (LIN), significantly inhibited SHP2 dephosphorylation activity in vitro. Cross-validated enzymatic assays, bio-layer interferometry (BLI) assays, and site-directed mutagenesis were used to confirm that LIN directly binds to the catalytic PTP domain of SHP2. In vivo administration of LIN significantly ameliorated carbon tetrachloride (CCl4)-induced HSC activation and liver fibrosis by inhibiting the TGFβ/Smad3 pathway. Thus, LIN or its derivatives could be considered potential therapeutic agents against SHP2-related diseases, such as liver fibrosis or NASH.

Rational combination of SHP2 and mTOR inhibition for the treatment of hepatocellular carcinoma.

Liver cancer is the fourth most common cause of cancer-related death worldwide, with hepatocellular carcinoma (HCC) being the main primary malignancy affecting the liver. Unfortunately, there are still limited therapeutic options for HCC, and even the latest advances have only increased the overall survival modestly. Thus, new treatment strategies and rational drug combinations are urgently needed. Reactivation of receptor tyrosine kinases (RTK) has been described as a mechanism of intrinsic resistance to targeted therapies in a variety of cancers, including inhibitors of mTOR. The design of rational combination therapies to overcome this type of resistance is complicated by the notion that multiple RTK can be upregulated during the acquisition of resistance. SHP2, encoded by the gene PTPN11, acts downstream of virtually all RTK, and has proven to be a good target for small molecule inhibitors. Here, we report activation of multiple RTK upon mTOR inhibition in HCC which, through SHP2, leads to reactivation of the mTOR pathway. We show that co-inhibition of both mTOR and SHP2 is highly synergistic in vitro by triggering apoptosis. More importantly, the combination is well-tolerated and outperforms the monotherapies in impairing tumor growth in multiple HCC mouse models. Our findings suggest a novel rational combination therapy for the treatment of HCC.

Developing SHP2-based combination therapy for KRAS-amplified cancer

Gastroesophageal adenocarcinomas (GEAs) harbor recurrent amplification of KRAS, leading to marked overexpression of WT KRAS protein. We previously demonstrated that SHP2 phosphatase, which acts to promote KRAS and downstream MAPK pathway activation, is a target in these tumors when combined with MEK inhibition. We hypothesized that SHP2 inhibitors may serve as a foundation for developing novel combination inhibitor strategies for therapy of KRAS-amplified GEA, including with targets outside the MAPK pathway. Here, we explore potential targets to effectively augment the efficacy of SHP2 inhibition, starting with genome-wide CRISPR screens in KRAS-amplified GEA cell lines with and without SHP2 inhibition. We identify candidate targets within the MAPK pathway and among upstream RTKs that may enhance SHP2 efficacy in KRAS-amplified GEA. Additional in vitro and in vivo experiments demonstrated the potent cytotoxicity of pan-ERBB kinase inhibitions in vitro and in vivo. Furthermore, beyond targets within the MAPK pathway, we demonstrate that inhibition of CDK4/6 combines potently with SHP2 inhibition in KRAS-amplified GEA, with greater efficacy of this combination in KRAS-amplified, compared with KRAS-mutant, tumors. These results suggest therapeutic combinations for clinical study in KRAS-amplified GEAs.

Exploiting Coordination Behavior of 7-Azaindole for Mechanistic Investigation of Chan-Lam Coupling and Application to 7-Azaindole Based Pharmacophores.

Multiple spectroscopic techniques, along with single-crystal X-ray analysis, have been used to reveal the detailed structural and electronic information on reaction intermediates of a new copper(II)-DBU catalytic system for the N-arylation of 7-Azaindole. The reaction mixture of Chan-Lam cross-coupling yields two dimeric copper(II)-7-azaindole complexes, including one attached with DBU, prior to adding arylboronic acid and are confirmed structurally and spectroscopically. A suitable mechanism has been proposed using the dimeric copper(II) complex as a catalyst for the coupling reactions. The role of DBU as a base and also as an auxiliary ligand in the course of the reaction has been established. The transmetalated monomeric aryl-copper(II) species generated from the dimeric unit is oxidized by another equivalent of copper(II) to yield an aryl-copper(III) intermediate for facile N-arylation, which has been authenticated with UV-vis spectroscopy. The regeneration of the copper(II)-catalyst by aerial oxidation of colorless copper(I) species (generated via reductive elimination and disproportionation step) is confirmed by mass and absorption spectroscopy. Detailed DFT and TD-DFT calculations help to rationalize the proposed reaction intermediates and their corresponding electronic transitions. Moreover, the confirmation of copper(I)-7-azaindole intermediate via HRMS reaffirmed the involvement of Cu(II)/Cu(III)/Cu(I) species in the Chan-Lam type of coupling. A medicinally-important 7-azaindole-based SHP2 inhibitor has been synthesized via sequential arylation.

Inhibition of SHP2 by the Small Molecule Drug SHP099 Prevents Lipopolysaccharide-Induced Acute Lung Injury in Mice.

Excessive pulmonary inflammation in acute lung injury (ALI) causes high patient mortality. Anti-inflammatory therapy, combined with infection resistance, can help to prevent ALI and save lives. The expression of Src homology-2 domain-containing protein tyrosine phosphatase 2 (SHP2) was found to be significantly higher in macrophages and lung tissues with ALI, and SHP2-associated MAPK pathways were activated by lipopolysaccharide (LPS). The knockdown of the SHP2 gene suppressed the LPS-induced release of inflammatory factors and the phosphorylation of regulators in the NF-κB pathways in macrophages. Our findings showed crosstalk between the LPS-induced inflammatory pathway and the SHP2-associated MAPK pathways. SHP2 inhibition could be a valuable therapeutic approach for inhibiting excessive inflammation in ALI. We discovered that giving SHP099, a specific allosteric inhibitor of SHP2, to mice with ALI and sepsis relieves ALI and significantly increases animal survival. Our study highlights the important role of SHP2 in ALI development and demonstrates the potential application of SHP099 for treating ALI.

Discovery of a Novel Series of Imidazopyrazine Derivatives as Potent SHP2 Allosteric Inhibitors.

Protein tyrosine phosphatase SHP2 is an oncogenic protein that can regulate different cytokine receptor and receptor tyrosine kinase signaling pathways. We report here the identification of a novel series of SHP2 allosteric inhibitors having an imidazopyrazine 6,5-fused heterocyclic system as the central scaffold that displays good potency in enzymatic and cellular assays. SAR studies led to the identification of compound 8, a highly potent SHP2 allosteric inhibitor. X-ray studies showed novel stabilizing interactions with respect to known SHP2 inhibitors. Subsequent optimization allowed us to identify analogue 10, which possesses excellent potency and a promising PK profile in rodents.

Early Combined SHP2 Targeting Reverses the Therapeutic Resistance of Vemurafenib in Thyroid Cancer.

The BRAFV600E mutation is the most common oncogenic mutation in thyroid cancer, suggesting an aggressive subtype of thyroid cancer and poor prognosis. Vemurafenib, a selective inhibitor of BRAFV600E, may provide therapeutic benefit in various cancers including thyroid cancer. However, the prevalence of drug resistance remains a challenge because of the feedback activation of the MAPK/ERK and PI3K/AKT pathways. In treating thyroid cancer cells with vemurafenib, we have detected reactivation of the MAPK/ERK signaling pathway as a result of the release of multiple receptor tyrosine kinases (RTKs) from the negative feedback of ERK phosphorylation. SHP2 is an important target protein downstream of the RTK signaling pathway. Decreasing it through SHP2 knockdown or the use of an inhibitor of SHP2 (SHP099) was found to significantly increase the early sensitivity and reverse the late resistance to vemurafenib in BRAFV600E mutant thyroid cancer cells. Overall, our findings suggest that blocking SHP2 reverses the reactivation of the MAPK/ERK signaling pathway caused by the activation of RTKs and improves the sensitivity of thyroid cancer to vemurafenib, which has potential implications for mechanism-based early combination strategies to treat thyroid cancer.

KMT2D deficiency drives lung squamous cell carcinoma and hypersensitivity to RTK-RAS inhibition.

Lung squamous cell carcinoma (LUSC) represents a major subtype of lung cancer with limited treatment options. KMT2D is one of the most frequently mutated genes in LUSC (>20%), and yet its role in LUSC oncogenesis remains unknown. Here, we identify KMT2D as a key regulator of LUSC tumorigenesis wherein Kmt2d deletion transforms lung basal cell organoids to LUSC. Kmt2d loss increases activation of receptor tyrosine kinases (RTKs), EGFR and ERBB2, partly through reprogramming the chromatin landscape to repress the expression of protein tyrosine phosphatases. These events provoke a robust elevation in the oncogenic RTK-RAS signaling. Combining SHP2 inhibitor SHP099 and pan-ERBB inhibitor afatinib inhibits lung tumor growth in Kmt2d-deficient LUSC murine models and in patient-derived xenografts (PDXs) harboring KMT2D mutations. Our study identifies KMT2D as a pivotal epigenetic modulator for LUSC oncogenesis and suggests that KMT2D loss renders LUSC therapeutically vulnerable to RTK-RAS inhibition.

Shp2 Deficiency in Kupffer Cells and Hepatocytes Aggravates Hepatocarcinogenesis by Recruiting Non-Kupffer Macrophages

Complex communications between hepatocytes and Kupffer cells (KCs) are known to drive or suppress hepatocarcinogenesis, with controversial data in the literature. In previous experiments that aimed to decipher hepatocyte/KC interactions, we unexpectedly unveiled a tumor-suppressing effect of polyinosinic-polycytidylic acid, a widely used inducer of MX dynamin like GTPase 1 (Mx1)-cre expression, which questioned a theory of interleukin 1a/6 cytokine circuit in hepatocyte/KC communication. The goal of this study was to clarify the controversy and decipher unique functions of KCs and non-KC macrophages in liver tumorigenesis. We used the C-type lectin domain family 4 member F (Clec4f)-cre system to delete Src-homology 2 domain-containing tyrosine phosphatase 2 (Shp2)/protein tyrosine phosphatase nonreceptor 11 (Ptpn11) in KCs, and a combination of Clec4f-cre and adeno-associated virus-cre to delete Shp2 in KCs and hepatocytes to investigate the effects on hepatocellular carcinoma development and immune cell compositions/activities. Ablating Shp2 in KCs generated a tumor-promoting niche, which was exacerbated further by concurrent removal of Shp2 in both KCs and hepatocytes. Shp2 deficiency induced KC apoptosis and decreased its numbers, which induced compensatory recruitment of bone marrow-derived monocytes into liver. These newly recruited monocytes differentiated into non-KC macrophages with tumor-associated macrophage function, leading to aggravated tumor progression through down-regulation of CD8 T cells. Tumor-associated macrophage blockade by anti-chemokine (C-C motif) ligand 2 (CCL2) antibody inhibited hepatocellular carcinoma progression, while depletion of all macrophages had a tumor-promoting effect by increasing myeloid-derived suppressor cells(M-MDSCs) and decreasing CD8 T cells. Shp2 loss in KCs or hepatocytes generated a protumorigenic microenvironment, which was exacerbated by its removal in both cell types. These results show the complexity of intercellular signaling events in liver tumorigenesis and raises caution on the use of specific Shp2 inhibitor in liver cancer therapy. Transcript profiling: RNA sequencing data are available at Gene Expression Omnibus (GSE222594).

How a single mutation alters the protein structure: a simulation investigation on protein tyrosine phosphatase SHP2.

Protein tyrosine phosphatase SHP2 is a key regulator modulating several signaling pathways. The oncogenic mutation E76K in SHP2 releases the enzyme from an autoinhibited, closed conformation into an active, open conformation. Here, we investigated the conformational dynamics of SHP2 and the effect of the E76K mutation on its conformational ensemble via extensive molecular dynamics (MD) and metadynamics (MetaD) simulations. Our simulations provide atomistic details on how the E76K mutated SHP2 prefers the open state and also reveal that the transition between the closed and the open states is highly collective. Several intermediate metastable states during the conformational transition between the closed and the open states were also investigated. Understanding how the single E76K mutation induces the conformational change in SHP2 could facilitate the further design of SHP2 inhibitors.

Metabolomic Strategy to Characterize the Profile of Secondary Metabolites in Aspergillus aculeatus DL1011 Regulated by Chemical Epigenetic Agents.

Chemical epigenetic regulation (CER) is an effective method to activate the silent pathway of fungal secondary metabolite synthesis. However, conventional methods for CER study are laborious and time-consuming. In the meantime, the overall profile of the secondary metabolites in the fungi treated by the CER reagent is not well characterized. In this study, suberohydroxamic acid (SBHA), a histone deacetylase inhibitor, was added to a culture of Aspergillus aculeatus DL1011 and a new strategy based on LC-MS/MS analysis integrated with various metabolomic tools (MetaboAnalyst, MS-DIAL, SIRIUS and GNPS) was developed to characterize the profile of induced metabolites. As a result, 13.6%, 29.5% and 27.2% of metabolites were identified as newly biosynthesized, increasing and decreasing in abundance by CER, respectively. The structures of the 18 newly induced secondary metabolites were further identified by the new strategy to demonstrate that 72.2% of them (1 novel compound and 12 known compounds) were first discovered in A. aculeatus upon SBHA treatment. The accuracy of the new approach was confirmed by purification and NMR data analysis of major newly biosynthesized secondary metabolites. The bioassay showed that the newly biosynthesized compounds, roseopurpurin analogues, showed selective activities against DPPH scavenging, cytotoxicity and SHP1 inhibition. Our research demonstrated that CER was beneficial for changing the secondary metabolic profile of fungi and was an effective means of increasing the diversity of active metabolites. Our work also supplied a metabolomic strategy to characterize the profile changes and determine the newly induced compounds in the secondary metabolites of fungi treated with the chemical epigenetic regulator.

Design and synthesis of improved active-site SHP2 inhibitors with anti-breast cancer cell effects

The Src homology containing phosphotyrosyl phosphatase 2 (SHP2) is a bona fide oncogene particularly in cancers driven by overexpression of receptor tyrosine kinases (RTKs). As such, there is a growing interest to target SHP2 in cancer. Based on these premises, several active site (type I) and allosteric site (type II) inhibitors have been developed, but no SHP2 targeting therapies have reached the clinic yet. In an effort to fill these gaps, we embarked on producing optimized versions of our parent active-site SHP2 inhibitor CNBDA. The objectives were to produce derivatives with increased inhibitory potential and improved selectivity. Accordingly, we designed derivatives around the CNBDA scaffold and predicted their binding property by in silico molecular modeling. Based on comparative differences in free energy of binding to the SHP2 versus the SHP1 active sites, ten were selected, chemically synthesized, and evaluated by NMR and mass spectroscopy for structural integrity. Among the ten derivatives, BPDA2 was found to be the most potent and highly selective compound, inhibiting the SHP2 enzyme activity with an IC50 of 92 nM when DiFMUP was used as a substrate and with an IC50 of 47 nM when pNPP was used as a substrate. Furthermore, enzyme kinetic analyses showed that BPDA2 is a competitive SHP2 inhibitor. Selectivity comparisons in a PTPase assay using DiFMUP as a substrate demonstrated that BPDA2 is more selective to SHP2 than to SHP1 and PTP1B by more than 369-fold and 442-fold, respectively. Evaluation with a cellular thermal shift assay (CETSA) confirmed that BPDA2 binds to wild-type SHP2 in a cellular context, and stabilizes it in solution. Treatment of cells with DBDA2 downregulates mitogenic and cell survival signaling and RTK expression in a concentration dependent manner. Furthermore, treatment of cells with BPDA2 suppresses anchorage independent growth and cancer stem cell properties of breast cancer cells. Overall, data described in this report show that BPDA2 is a more potent derivative of CNBDA with a highly improved selectivity for SHP2.

SHP1 loss augments DLBCL cellular response to ibrutinib: a candidate predictive biomarker.

SHP1, a tyrosine phosphatase, negatively regulates B-cell receptor (BCR) signaling. Ibrutinib selectively inhibits BTK and has been approved for the treatment of several types of B-cell lymphomas, but not yet in diffuse large B-cell lymphoma (DLBCL). A phase 3 clinical trial of ibrutinib-containing regimen has been completed to evaluate its activity in subtypes or subsets of DLBCL patients. Although the subtype of activated B-cell like (ABC) DLBCL is characterized by chronic active BCR signaling, only a fraction of ABC-DLBCL patients seem to benefit from ibrutinib-containing regimen. New alternative predictive biomarkers are needed to identify patients who better respond. We investigated if SHP1 plays a role in defining the level of the BCR activity and impacts the response to ibrutinib. A meta-analysis revealed that lack of SHP1 protein expression as well as SHP1 promoter hypermethylation is strongly associated with NHL including DLBCL. On a tissue microarray of 95 DLBCL samples, no substantial difference in SHP1 expression was found between the GCB and non-GCB subtypes of DLBCL. However, we identified a strong reverse correlation between SHP1 expression and promoter methylation suggesting that promoter hypermethylation is responsible for SHP1 loss. SHP1 knockout in BCR-dependent GCB and ABC cell lines increased BCR signaling activities and sensitize lymphoma cells to the action of ibrutinib. Rescue of SHP1 in the knockout clones, on the other hand, restored BCR signaling and ibrutinib resistance. Further, pharmacological inhibition of SHP1 in both cell lines and patient-derived primary cells demonstrate that SHP1 inhibition synergized with ibrutinib in suppressing tumor cell growth. Thus, SHP1 loss may serve as an alternative biomarker to cell-of-origin to identify patients who potentially benefit from ibrutinib treatment. Our results further suggest that reducing SHP1 pharmacologically may represent a new strategy to augment tumor response to BCR-directed therapies. Schematic diagram summarizing the major findings. Left panel. When SHP1 is present and functional, it negatively regulates the activity of the BCR pathway. Right pane. When SHP1 is diminished or lost, cells depend more on the increased BCR signaling and making them vulnerable to BTK inhibitor, ibrutinib. Diagram was generated using BioRender.

SHP2 inhibition mitigates adaptive resistance to MEK inhibitors in KRAS-mutant gastric cancer through the suppression of KSR1 activity

Despite the promising antitumor activity of RAF/MEK inhibitors for RAS-driven cancers, not all patients respond to these therapies. Adaptive resistance has been reported as a major culprit in non-responders, which can be reversed by SHP2 inhibitors (SHP2is) in multiple cancer cells; however, the underlying mechanisms remain unknown. In this study, we found that KRAS-mutant gastric cancer cells respond to MEK inhibitors (MEKis) with adaptive resistance. Markedly, SHP2 activation accompanied by ERK signaling restoration in MEKi-treated cells, and a MEKi and SHP2i combination had a synergistic effect on downstream signaling blockade. In vivo, SHP099 combined with AZD6244 (selumetinib) was highly efficacious for the treatment of xenografts. Mechanistically, SHP2 was found to interact with the scaffold protein KSR1 through its protein tyrosine phosphatase domain. KSR1 knockdown sensitized cells to AZD6244, whereas a KSR1 activating mutation (S269A) diminished the synergistic anti-proliferative effect of SHP2i and MEKi. Interestingly, activated SHP2, during adaptive resistance to MEKis, impaired the interaction with KSR1, activating KSR1 to promote MAPK signaling. In conclusion, SHP2 promotes adaptive resistance to MEKis by activating KSR1; selumetinib combined with SHP099 might be an available therapeutic strategy for KRAS-mutant gastric cancers.

Drug response profiles in patient-derived cancer cells across histological subtypes of ovarian cancer: real-time therapy tailoring for a patient with low-grade serous carcinoma

Many efforts are underway to develop novel therapies against the aggressive high-grade serous ovarian cancers (HGSOCs), while our understanding of treatment options for low-grade (LGSOC) or mucinous (MUCOC) of ovarian malignancies is not developing as well. We describe here a functional precision oncology (fPO) strategy in epithelial ovarian cancers (EOC), which involves high-throughput drug testing of patient-derived ovarian cancer cells (PDCs) with a library of 526 oncology drugs, combined with genomic and transcriptomic profiling. HGSOC, LGSOC and MUCOC PDCs had statistically different overall drug response profiles, with LGSOCs responding better to targeted inhibitors than HGSOCs. We identified several subtype-specific drug responses, such as LGSOC PDCs showing high sensitivity to MDM2, ERBB2/EGFR inhibitors, MUCOC PDCs to MEK inhibitors, whereas HGSOCs showed strongest effects with CHK1 inhibitors and SMAC mimetics. We also explored several drug combinations and found that the dual inhibition of MEK and SHP2 was synergistic in MAPK-driven EOCs. We describe a clinical case study, where real-time fPO analysis of samples from a patient with metastatic, chemorefractory LGSOC with a CLU-NRG1 fusion guided clinical therapy selection. fPO-tailored therapy with afatinib, followed by trastuzumab and pertuzumab, successfully reduced tumour burden and blocked disease progression over a five-year period. In summary, fPO is a powerful approach for the identification of systematic drug response differences across EOC subtypes, as well as to highlight patient-specific drug regimens that could help to optimise therapies to individual patients in the future.

Targeting KRASp.G12C Mutation in Advanced Non-Small Cell Lung Cancer: a New Era Has Begun.

KRASp.G12C mutation occurs in 12% of newly diagnosed advanced NSCLC and has recently emerged as a positive predictive biomarker for the selection of advanced NSCLC patients who may respond to novel KRASp.G12C inhibitors. The recent discovery of a new binding pocket under the effector region of KRAS G12C oncoprotein has made direct pharmacological inhibition of the KRASp.G12 mutation possible, leading to the clinical development of a new series of direct selective inhibitors, with a potential major impact on patients' survival and quality of life. Promising efficacy and tolerability data emerging from the early phase CodeBreak trial have already supported the regulatory approval of sotorasib as first in class targeted treatment for the second-line treatment of KRASp.G12C-positive NSCLC population, following immunotherapy-based first-line therapies, while the randomized phase III CodeBreak 200 clinical study has recently confirmed a significant superiority of sotorasib over docetaxel in terms of progression-free survival and quality of life. However, KRAS mutant NSCLC is a high heterogeneous disease characterized by a high rate of co-mutations, most frequently involving P53, STK11, and KEAP1 genes, which significantly modulate the composition of the tumor microenvironment and consequently affect clinical responses to both immunotherapy and targeted inhibitors now available in clinical practice. Both pre-clinical and clinical translational series have recently revealed a wide spectrum of resistance mechanisms occurring under selective KRASG12C inhibitors, including both on-target and off-target molecular alterations as well as morphological switching, negatively affecting the antitumor activity of these drugs when used as single agent therapies. The understanding of such biological background along with the emergence of pre-clinical data provided a strong rational to investigate different combination strategies, including the inhibition of SHP2, SOS1, and KRAS G12C downstream effectors, as well as the addition of immunotherapy and/or chemotherapy to targeted therapy. The preliminary results of these trials have recently suggested a promising activity of SHP2 inhibitors in the front-line setting, while toxicity issues limited the concurrent administration of immune-checkpoint inhibitors and sotorasib. The identification of predictive genomic/immunological biomarkers will be crucial to understand how to optimally sequencing/combining different drugs and ultimately personalize treatment strategies under clinical investigation, to definitively increase the survival outcomes of KRASp.G12C mutant advanced NSCLC patients.

A novel GRK2 inhibitor alleviates experimental arthritis through restraining Th17 cell differentiation

T helper type 17 (Th17) cell which is induced by interleukine-6 (IL-6)-signal transducers and activators of transcription 3 (STAT3) signaling is a central pro-inflammatory T cell subtype in rheumatoid arthritis (RA) and could be significantly reduced by paeoniflorin-6′-O-benzene sulfonate (CP-25) treatment with unclear mechanisms. This study was aimed to found out the mechanism of CP-25 in hampering Th17 cells differentiation in arthritic animals thus explore more therapeutic targets for RA. In mice with collagen-induced arthritis (CIA), both circulating and splenic Th17 subsets were expanded with increased STAT3 phosphorylation and decreased Src homology 2 domain-containing protein tyrosine phosphatase 1 (SHP1)-β-arrestin2 (arrb2)-STAT3 interaction in CD4+ helper T (Th) cells. Either CP-25 or paroxetine (PAR), an established G protein coupled receptor kinase 2 (GRK2) inhibitor treatment effectively relieved the joints inflammation of CIA mice with substantially reduced Th17 cell population through inhibiting STAT3 and restoring the SHP1-arrb2-STAT3 complex. Knockout of arrb2 exacerbated the clinical manifestations of collagen antibody-induced arthritis with upregulated Th17 cells. In vitro studies revealed that depletion of arrb2 or inhibition of SHP1 promoted Th17 cell differentiation. Moreover, stimulation of adenosine A3 receptor (A3AR) simultaneously promoted Th17 cell differentiation via accelerating abbr2-A3AR binding, which could be prevented through inhibiting GRK2 phosphorylation by CP-25 or PAR, or genetically reducing GRK2. This work has demonstrated that CP-25 or PAR treatment recovers the SHP1-arrb2-STAT3 complex which prevents STAT3 activation in Th cells through reducing arrb2 recruitment to A3AR by inhibiting GRK2 phosphorylation, leading to the reduction in Th17 cell differentiation and arthritis attenuation.