GRP78 blockade overcomes acquired resistance to EGFR-tyrosine kinase inhibitors in non-small cell lung cancer

AIMS

While significant upregulation of GRP78 has been documented in lung cancer patients, its association with resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) remains underexamined. Our study aimed to elucidate the functional importance of GRP78 in acquired resistance to EGFR-TKIs in non-small cell lung cancer (NSCLC) and to evaluate its potential as a therapeutic target.

MAIN METHODS

Immunoblot analysis or flow cytometry was employed to assess several markers for endoplasmic reticulum (ER) stress and apoptosis. Ru(II) complex I and HA15, two known GRP78 inhibitors, were used to evaluate the functional role of GRP78. A Xenograft assay was performed to evaluate the in vivo anti-cancer effects of the GRP78 inhibitors.

KEY FINDINGS

We validated a significant increase in GRP78 protein levels in HCC827-GR, H1993-GR, and H1993-ER cells. The EGFR-TKI-resistant cells overexpressing GRP78 exhibited significantly higher cell proliferation rates than did their parental counterparts. Notably, GRP78 inhibition resulted in a more profound anti-proliferative and apoptotic response via heightened ER stress and subsequent reactive oxygen species (ROS) production in EGFR-TKI-resistant cell lines compared with their parental cells. In xenograft models implanted with HCC827-GR, both Ru(II) complex I and HA15 significantly suppressed tumor growth and reduced tumor weight. Additionally, we confirmed that GRP78 plays a critical role in the proliferation of H1975, an EGFR-TKI-resistant T790M-mutant cell line, relative to other NSCLC cell lines.

SIGNIFICANCE

Our findings strongly support targeting of GRP78 as a promising therapeutic strategy for NSCLC patients with acquired resistance to EGFR-TKIs.

Abstract 4023: Inhitibing GRP78 in non-small cell lung cancer with acquired resistance to EGFR-TKI

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have improved the survival of non small cell lung cancer (NSCLC) patients with active mutation of EGFR. However, some of the patients who received EGFR-TKIs showed the acquired resistance, and eventually relapsed within several months. In the TCGA data sets, gene expression of glucose-related protein 78 (GRP78), an ER chaperone, was upregulated in NSCLC tissues. We also confirmed that protein level of GRP78 was increased in HCC827-GR, H1993-GR and H1993-ER NSCLC cell lines with acquired resistance to EGFR-TKIs. Since GRP78 modulates ER stress level which induces ROS and apoptosis, Ru(II) complex 1 and HA15, both the known GRP78 inhibitors induced higher ER stress and ROS generation accompanying more remarkable anti-proliferative and apoptotic effects in EGFR-TKI-resistant NSCLC cell lines. GRP78 level was also found to be higher in H1975, EGFR-TKI-resistant T790M-mutant cell line than other NSCLC cell lines. Blockade of GRP78 also led to apoptosis in H1975, which is consistent with the results found in the acquired EGFR-TKI-resistant cell lines. In summary, we suggest GRP78 targeting as a potential therapeutic strategy for the acquired EGFR-TKI-resistant NSCLC patients.

Citation Format: Jaewoo Park, Baskaran Purushothaman, Sera Hong, Munkyung Choi, Joon Myong Song, Keon Wook Kang. Inhitibing GRP78 in non-small cell lung cancer with acquired resistance to EGFR-TKI. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4023.

Drug delivery in transarterial chemoembolization of hepatocellular carcinoma: Ex vivo evaluation using transparent tissue imaging

In this study, we elucidated for the first time the role of anti-cancer drugs in transarterial chemoembolization (TACE) via direct visualization of the spatial distribution of drugs with respect to blood vessels in intact transparent hepatocellular carcinoma (HCC) tissues. To date, precise estimation of drug penetration into tumors using thin 3D tissue sections has been challenging. This study utilized the tissue optical clearing technique to resolve the lack of tissue clarity, thereby enabling deep tissue imaging for the quantitative assessment of drug delivery following TACE. We compared the drug delivery effect, time-dependent embolic effect, and immunogenic response following conventional TACE (cTACE), drug-eluting embolic TACE (DEE-TACE), and transarterial embolization (TAE) in a rat model of HCC. After each treatment, three-dimensional drug delivery was quantitatively evaluated via the transparent liver tumor imaging, and time-dependent tumor necrosis was analyzed by serial tumor harvesting and histological staining. The results showed that chemotherapeutic agents travel only short distances after cTACE (∼80µm) and DEE-TACE (∼110µm), whereas necrosis occurs extensively within 24 h of treatment (85.3-97.2% of tumor cells). In addition, the percentages of CD4 and IL-17+ CD4 T cells increased significantly following treatment; however, drug-loading did not appear to affect the immune response following TACE. In conclusion, transarterially delivered chemotherapeutic agents appeared to exert a limited role, owing to the rapid and overwhelming effect of embolization. STATEMENT OF SIGNIFICANCE: TACE has been widely used for the treatment of HCC, especially for unresectable intermediate and advanced HCCs. Drug use in TACE is expected to provide patients with synergistic therapeutic benefits with the effect of embolic agents; however, the role of chemotherapeutic agents in TACE remains controversial. This study quantitatively verified that chemotherapeutic agents travel only short distances after TACE, while necrosis occurs extensively within 24h, and drug loading does not significantly affect immune responses following TACE. Three-dimensional imaging of intact transparent HCC can contribute to a better understanding of drug delivery mechanisms associated with TACE and also reveal that drug use in TACE may need to be reconsidered and limited to situations when embolization is expected to be insufficient.

Ag2S quantum dot theragnostics

Silver sulfide quantum dots (Ag₂S QDs) as a theragnostic agent have received much attention because they provide excellent optical and chemical properties to facilitate diagnosis and therapy simultaneously.

Multifunctional TPP-PEG-biotin self-assembled nanoparticle drug delivery-based combination therapeutic approach for co-targeting of GRP78 and lysosome

Background

In this study, a multifunctional tetraphenylporphyrin (TPP) conjugated polyethylene glycol with biotin (TPP-PEG-biotin) as a photo-dynamic therapy (PDT) material encapsulating a ruthenium complex 1 (Ru-1) was fabricated as self-assembled nanoparticle (Ru-1@TPP-PEG-biotin SAN) to co-target glucose-regulated protein 78 (GRP78) and the lysosome as a new anti-cancer therapeutic strategy.

Results

The MTT assay results reveals the enhanced anticancer activity of the Ru-1@TPP-PEG-biotin SANs due to the co-targeting of the GRP78 and lysosome. The Ru-1@TPP-PEG-biotin reduced level of GRP78 and lysosomal ceramide that contributed to the stability of the lysosomal membrane. The endoplasmic reticulum (ER) stress concomitant with the inhibition of GRP78 was clearly monitored by the phosphorylation of protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK), and inositol-requiring enzyme 1 α (IRE1α) kinases to indicate the activation of the unfolded protein response (UPR) signaling using immunofluorescence assay. On the other hand, the degradation of the lysosome was observed through PDT action by the Ru-1@TPP-PEG-biotin SAN treatment. This was confirmed by the co-localization assay showing the disappearance of cathepsin D and lysosomal-associated membrane protein 1 (LAMP1) in the lysosome.

Conclusions

Considering lysosome-mediated autophagy is an effective cancer cell survival mechanism, the degradation of the lysosome along with GRP78 inhibition by the Ru-1@TPP-PEG-biotin SAN combination therapy is suggested as a new co-targeting cancer treatment.

Inkjet Bioprinting on Parchment Paper for Hit Identification from Small Molecule Libraries

In this study, an inkjet bioprinting-based high-throughput screening (HTS) system was designed and applied for the first time to a catecholpyrimidine-based small molecule library to find hit compounds that inhibit c-Jun NH₂-terminal kinase1 (JNK1). JNK1 kinase, inactivated MAPKAPK2, and specific fluorescent peptides along with bioink were printed on parchment paper under optimized printing conditions that did not allow rapid evaporation of printed media based on Triton-X and glycerol. Subsequently, different small compounds were printed and tested against JNK1 kinase to evaluate their degree of phosphorylation inhibition. After printing and incubation, fluorescence intensities from the phosphorylated/nonphosphorylated peptide were acquired for the % phosphorylation analysis. The IM₅₀ (inhibitory mole 50) value was determined as 1.55 × 10^-15 mol for the hit compound, 22. Thus, this work demonstrated that inkjet bioprinting-based HTS can potentially be adopted for the drug discovery process using small molecule libraries, and cost-effective HTS can be expected to be established based on its low nano- to picoliter printing volume.

Biotin-conjugated PEGylated porphyrin self-assembled nanoparticles co-targeting mitochondria and lysosomes for advanced chemo-photodynamic combination therapy

In this study, the chemo-drug doxorubicin (DOX) was successfully encapsulated in PEG–biotin conjugated porphyrin SANs (DOX@TPP–PEG–biotin) and had synergistic effects after PDT action.

A Novel Catecholopyrimidine Based Small Molecule PDE4B Inhibitor Suppresses Inflammatory Cytokines in Atopic Mice

Degradation of cyclic adenosine mono phosphate (cAMP) by phosphodiesterase-4B (PDE-4B) in the inflammatory cells leads to elevated expression of inflammatory cytokines in inflammatory cells. Suppression of cytokines has proved to be beneficial in the treatment of atopic dermatitis (AD). Henceforth, application of PDE4B specific inhibitor to minimize the degradation of cAMP can yield better results in the treatment of AD. PDE4B specific inhibitor with a limited side effect is highly warranted. Herein, we synthesized a novel PDE4 inhibitor, compound 2 comprising catecholopyrimidine core functionalized with trifluoromethyl (-CF₃) group. PDE4B inhibitory potential and specificity of novel compounds were evaluated by PDE inhibitor assay. In vivo efficacy of the compounds was analyzed using DNCB-induced NC/Nga mice. IgE, CD4+ T-helper cell infiltration, and cytokine profiles were analyzed by ELISA and immunohistochemistry techniques. Toluidine blue staining was performed for mast cell count. PDE4 inhibitor assay confirmed that compound 2 specifically inhibits PDE4B. In vivo analysis with DNCB-induced NC/Nga mice confirmed that compound 2 suppressed the levels of pro-inflammatory cytokines such as TNF-α, IL-4, IL-5, and IL-17. Furthermore, compound 2 significantly reduced the infiltrative CD4+ T-helper cells, mast cells and IgE levels in atopic tissue. The in vitro and in vivo data suggested that compound 2 specifically inhibit the PDE4B and the symptoms of the AD in atopic mice. Compound 2 might constitute a good candidate molecule for the treatment of AD.

Quantum-dot nanoprobes and AOTF based cross talk eliminated six color imaging of biomolecules in cellular system

Primary cell cultures mimic the physiology and genetic makeup of in-vivo tissue of origin, nonetheless, a complication in the derivation and propagation of primary cell culture limits its use in biological research. However, in-vitro models using primary cells might be a complement model to mimic in vivo response. But, conventional techniques such as western blot and PCR employed to study the expression and activation of proteins requires a large number of cells, hence repeated establishment and maintenance of primary culture are unavoidable. Quantum dot (Q-dot) and acousto-optic tunable filters (AOTF) based multiplex imaging system is a viable alternative choice to evaluate multiple signaling molecules by using a small number of cells. Q-dots have broad excitation and narrow emission spectra, which allows to simultaneously excite multiple Q-dots by using single excitation wavelength. The use of AOTF in the fluorescence detection system enables to scan the fluorescence emission intensity of a Q-dot at their central wavelength, this phenomenon effectively avoids spectral overlap among the neighboring Q-dots. When Q-dots are conjugated with antibodies it acts as effective sensing probes. To validate this, the expression pattern of p-JNK-1, p-GSK3β, p-IRS1ser, p-IRS1tyr, p-FOXO1, and PPAR-γ, involved in the insulin resistance were concurrently monitored in adipocyte and HepG2 co-cell culture model. The observed results clearly indicate that PPAR-γ is the critical component in the development of insulin resistance. Moreover, the results proved that developed Q-dot based AOTF imaging methodology is a sensible choice to concurrently monitor multiple signaling molecules with limited cell population.

Decision making on timing of surgery for hip fracture patients on clopidogrel

Patients taking clopidogrel who sustain a fractured neck of femur pose a challenge to orthopaedic surgeons. The aim of this study was to determine whether delay to theatre for these patients affects drop in haemoglobin levels, need for blood transfusion, length of hospital stay and 30-day mortality. A retrospective review of all neck of femur patients admitted at two centres in the North East of England over 3 years revealed 85 patients. Patients were divided into two groups depending on whether they were taking clopidogrel alone (C) or with aspirin (CA). Haemoglobin drop was significantly different in the CA group that was operated on early (CA1) versus the group for which surgery was delayed by over 48 hours (CA2): 3.3g/dl and 1.9g/dl respectively (p=0.01). The mean inpatient stay in group C was 35.9 days while in group CA it was 19.9 days (p=0.002). The mean length of stay in group CA2 (26.7 days) was significantly longer than for CA1 patients (14.1 days) (p=0.01). There were no significant differences in mortality or wound complications. Hip fracture patients on clopidogrel can be safely operated on early provided they are medically stable. Bleeding risk should be borne in mind in those patients on dual therapy with aspirin.

Insulin-mimetic and anti-inflammatory potential of a vanadyl-Schiff base complex for its application against diabetes

Insulin-mimetic and anti-inflammatory potential of vanadium oxo complex (VOTP) enhances the GLUT4 translocation by inducing the phosphorylation of tyrosine moiety in insulin receptor substrate (IRS1).

Outcome of lumbar spinal fusion surgery in obese patients

The aim of this study was to determine whether obesity affects pain, surgical and functional outcomes following lumbar spinal fusion for low back pain (LBP).

A systematic literature review and meta-analysis was made of those studies that compared the outcome of lumbar spinal fusion for LBP in obese and non-obese patients. A total of 17 studies were included in the meta-analysis. There was no difference in the pain and functional outcomes. Lumbar spinal fusion in the obese patient resulted in a statistically significantly greater intra-operative blood loss (weighted mean difference: 54.04 ml; 95% confidence interval (CI) 15.08 to 93.00; n = 112; p = 0.007) more complications (odds ratio: 1.91; 95% CI 1.68 to 2.18; n = 43858; p < 0.001) and longer duration of surgery (25.75 mins; 95% CI 15.61 to 35.90; n = 258; p < 0.001). Obese patients have greater intra-operative blood loss, more complications and longer duration of surgery but pain and functional outcome are similar to non-obese patients. Based on these results, obesity is not a contraindication to lumbar spinal fusion.

Cite this article: Bone Joint J 2015;97-B:1395–1404.

Delayed ulnar nerve palsy secondary to ulnar artery pseudoaneurysm distal to Guyon's canal following penetrating trauma to the hand

Compression of the ulnar nerve in Guyon's canal is an uncommon phenomenon. Reports of ulnar nerve palsy secondary to ulnar artery pseudoaneurysm at this anatomical location are very rare and equivalent pathology just distal to this site is unheard of. Here we present such a case, which featured a delayed onset of symptoms. This followed penetrating trauma to the hand. Our methods for diagnosis, operative planning and surgical treatment are included.

Importance of spin-orbit interaction for the electron spin relaxation in organic semiconductors

Despite the great interest organic spintronics has recently attracted, there is only a partial understanding of the fundamental physics behind electron spin relaxation in organic semiconductors. Mechanisms based on hyperfine interaction have been demonstrated, but the role of the spin-orbit interaction remains elusive. Here, we report muon spin spectroscopy and time-resolved photoluminescence measurements on two series of molecular semiconductors in which the strength of the spin-orbit interaction has been systematically modified with a targeted chemical substitution of different atoms at a particular molecular site. We find that the spin-orbit interaction is a significant source of electron spin relaxation in these materials.

Ligamentotaxis for Barton's and paediatric distal radial fractures

PURPOSE

To establish a consensus regarding immobilisation of the wrist following reduction of Barton's and paediatric distal radial fractures.

METHODS

Questionnaires were distributed to orthopaedic surgeons at the European Federation of National Associations of Orthopaedics and Traumatology meeting in Lisbon in 2005. Questions included the surgeon's country of practice, hospital, professional grade, years of experience, sub-specialty, and preferred position of wrist immobilisation after (1) a volar Barton's fracture, (2) a dorsal Barton's fracture, (3) a paediatric Salter-Harris type-II injury to the distal radius with volar displacement, and (4) the same injury but with dorsal displacement.

RESULTS

Of 148 questionnaires distributed, 118 were returned. The specialist-to-trainee ratio was 45:73. In volar Barton's fractures, only 20% (29% specialists and 15% trainees) would immobilize the wrist in palmar flexion, as per recommendations. In dorsal Barton's fractures, only 25% (33% specialists and 21% trainees) would immobilize the wrist in dorsiflexion, as per recommendation. In paediatric Salter Harris type-II injury to the distal radius with volar displacement, 87% (100% specialists and 79% trainees) would immobilize the wrist in dorsiflexion or in a neutral position, as per recommendation. In the same injury but with dorsal displacement, 84% (89% specialists and 81% trainees) would immobilize the wrist in palmar flexion or in a neutral position, as per recommendation. In all 4 types of fractures, 26% to 30% of respondents would immobilize the wrist in a neutral position.

CONCLUSION

Most respondents deviate from the recommended immobilisation positions in treating Barton's fractures. Understanding of the anatomy or biomechanics of ligamentotaxis are crucial for conservative treatments.

[5,10,15,20-Tetrakis(2-thienyl)-porphyrinato]zinc(II)

In the title complex, [Zn(C(36)H(20)N(4)S(4))], the Zn(II) ion occupies a special position on an inversion centre with four-coordinate geometry. The porphyrin ring shows a wave-like conformation, with the closest interporphyrin plane separation being 3.60 (6) A. The two disordered thienyl groups are inclined with respect to the porphyrin plane at angles of 70 (4) and 67 (2) degrees.