A Review of Monoclonal Antibody-Based Treatments in Non-small Cell Lung Cancer

Lung cancer organoids: models for preclinical research and precision medicine

Lung cancer is a malignancy with high incidence and mortality rates globally, and it has a 5-year survival rate of only 10%-20%. The significant heterogeneity in clinical presentation, histological features, multi-omics findings, and drug sensitivity among different lung cancer patients necessitate the development of personalized treatment strategies. The current precision medicine for lung cancer, primarily based on pathological and genomic multi-omics testing, fails to meet the needs of patients with clinically refractory lung cancer. Lung cancer organoids (LCOs) are derived from tumor cells within tumor tissues and are generated through three-dimensional tissue culture, enabling them to faithfully recapitulate in vivo tumor characteristics and heterogeneity. The establishment of a series of LCOs biobanks offers promising platforms for efficient screening and identification of novel targets for anti-tumor drug discovery. Moreover, LCOs provide supplementary decision-making factors to enhance the current precision medicine for lung cancer, thereby addressing the limitations associated with pathology-guided approaches in managing refractory lung cancer. This article presents a comprehensive review on the construction methods and potential applications of LCOs in both preclinical and clinical research. It highlights the significance of LCOs in biomarker exploration, drug resistance investigation, target identification, clinical precision drug screening, as well as microfluidic technology-based high-throughput drug screening strategies. Additionally, it discusses the current limitations and future prospects of this field.

Enhanced in vivo anti-tumor efficacy of whole tumor lysate in combination with whole tumor cell-specific polyclonal antibody

Background and purpose

Despite the widespread utilization of cancer vaccines with specified antigens, the use of whole tumor cell lysates in tumor immunotherapy would be a very promising approach that can overcome several significant obstacles in vaccine production. Whole tumor cells provide a broad source of tumor-associated antigens and can activate cytotoxic T lymphocytes and CD4+ T helper cells concurrently. On the other hand, as an effective immunotherapy strategy, recent investigations have shown that the multi-targeting of tumor cells with polyclonal antibodies, which are also more effective than monoclonal antibodies at mediating effector functions for target elimination, might minimize the escape variants.

Experimental approach

We prepared polyclonal antibodies by immunizing rabbits with the highly invasive 4T1 breast cancer cell line.

Findings/Results

In vitro investigation indicated that the immunized rabbit serum inhibited cell proliferation and induced apoptosis in target tumor cells. Moreover, in vivo analysis showed enhanced anti-tumor efficacy of whole tumor cell lysate in combination with tumor cell-immunized serum. This combination therapy proved beneficial in significant inhibition of the tumor growth and the established tumor was entirely eradicated in treated mice.

Conclusion and implications

Serial intravenous injections of tumor cell immunized rabbit serum significantly inhibited tumor cell proliferation and induced apoptosis in vitro and in vivo in combination with whole tumor lysate. This platform could be a promising method for developing clinical-grade vaccines and open up the possibility of addressing the effectiveness and safety of cancer vaccines.

Inhalable neutralizing antibodies - promising approach to combating respiratory viral infections

Monoclonal antibodies represent an exciting class of therapeutics against respiratory viral infections. Notwithstanding their specificity and affinity, the conventional parenteral administration is suboptimal in delivering antibodies for neutralizing activity in the airways due to the poor distribution of macromolecules to the respiratory tract. Inhaled therapy is a promising approach to overcome this hurdle in a noninvasive manner, while advances in antibody engineering have led to the development of unique antibody formats which exhibit properties desirable for inhalation. In this Opinion, we examine the major challenges surrounding the development of inhaled antibodies, identify knowledge gaps that need to be addressed and provide strategies from a drug delivery perspective to enhance the efficacy and safety of neutralizing antibodies against respiratory viral infections.

Combination of GNRs-PEI/cGAMP-laden macrophages-based photothermal induced in situ tumor vaccines and immune checkpoint blockade for synergistic anti-tumor immunotherapy

Immunotherapy is an effective strategy to control and eliminate primary and metastatic tumor by restarting and restoring the specific anti-tumor immune response. However, tumor immunotherapy often showed limited efficacy due to the poor T cell responses in vivo and the tumor suppressive microenvironments. Herein, we constructed polyethyleimine modified gold nanorods (GNRs-PEI) by conjugating PEI to GNRs via SAu bonds. GNRs-PEI/cGAMP nanoparticles were formed via electrostatic interaction and then loaded by macrophages. The GNRs-PEI/cGAMP-laden macrophages (GPc-RAWs) were intravenously injected into the tumor bearing mice and the in situ tumor vaccines were obtained after NIR irradiation. Besides, anti-PD-L1 antibody, an immune checkpoint inhibitor, was introduced to reverse immunosuppressive microenvironment and assisted to achieve the synergistic anti-tumor immunotherapy. GNRs-PEI/cGAMP-laden macrophages with NIR irradiation could effectively inhibit the primary tumors, while little effect for the contralateral tumors. When combined with anti-PD-L1 antibody, the combined strategy not only inhibited the growth of primary tumor, but also significantly delayed the proliferation of the contralateral tumors. More importantly, this strategy reversed immunosuppressive microenvironment without obvious side effects. Therefore, this study provided a great immunotherapy platform for the efficient treatment of primary and metastatic tumors.

GZ17-6.02 and Pemetrexed Interact to Kill Osimertinib-Resistant NSCLC Cells That Express Mutant ERBB1 Proteins

We determined the molecular mechanisms by which the novel therapeutic GZ17-6.02 killed non-small cell lung cancer (NSCLC) cells. Erlotinib, afatinib, and osimertinib interacted with GZ17-6.02 to kill NSCLC cells expressing mutant EGFR proteins. GZ17-6.02 did not interact with any EGFR inhibitor to kill osimertinib-resistant cells. GZ17-6.02 interacted with the thymidylate synthase inhibitor pemetrexed to kill NSCLC cells expressing mutant ERBB1 proteins or mutant RAS proteins or cells that were resistant to EGFR inhibitors. The drugs interacted to activate ATM, the AMPK, and ULK1 and inactivate mTORC1, mTORC2, ERK1/2, AKT, eIF2α; and c-SRC. Knockdown of ATM or AMPKα₁ prevented ULK1 activation. The drugs interacted to cause autophagosome formation followed by flux, which was significantly reduced by knockdown of ATM, AMPKα₁, and eIF2α, or by expression of an activated mTOR protein. Knockdown of Beclin1, ATG5, or [BAX + BAK] partially though significantly reduced drug combination lethality as did expression of activated mTOR/AKT/MEK1 or over-expression of BCL-XL. Expression of dominant negative caspase 9 weakly reduced killing. The drug combination reduced the expression of HDAC2 and HDAC3, which correlated with lower PD-L1, IDO1, and ODC levels and increased MHCA expression. Collectively, our data support consideration of combining GZ17-6.02 and pemetrexed in osimertinib-resistant NSCLC.

Osimertinib-resistant NSCLC cells activate ERBB2 and YAP/TAZ and are killed by neratinib

We performed additional mechanistic analyses to redefine neratinib biology and determined the mechanisms by which the multi-kinase inhibitor neratinib interacted with the thymidylate synthase inhibitor pemetrexed to kill NSCLC cells expressing either mutant KRAS (G12S; Q61H; G12A; G12C) or mutant NRAS (Q61K) or mutant ERBB1 (L858R; L858R T790M; exon 19 deletion). Neratinib rapidly reduced KRASG12V and RAC1G12V nanoclustering which was followed by KRASG12V, but not RAC1G12V, being extensively mislocalized away from the plasma membrane. This correlated with reduced levels of, and reorganized membrane localization of phosphatidylserine and cholesterol. Reduced nanoclustering was not associated with inactivation of ERBB1, Merlin or Ezrin. The drug combination killed cells expressing mutant KRAS, NRAS or mutant ERBB1 proteins. Afatinib or osimertinib resistant cells were killed with a similar efficacy to non-resistant cells. Compared to osimertinib-resistant cells, sensitive cells had less ERBB2 Y1248 phosphorylation. In osimertinib resistant H1975 cells, the drug combination was less capable of inactivating AKT, mTOR, STAT3, STAT5, ERK1/2 whereas it gained the ability to inactivate ERBB3. In resistant H1650 cells, the drug combination was less capable of inactivating JAK2 and STAT5. Sensitive cells exhibited elevated basal phosphorylation of YAP and TAZ. In resistant cells, portions of YAP and TAZ were localized in the nucleus. [Neratinib + pemetrexed] increased phosphorylation of YAP and TAZ, caused their nuclear exit, and enhanced ERBB2 degradation. Thus, neratinib targets an unidentified protein whose functional inhibition directly results in RAS inactivation and tumor cell killing. Our data prove that, albeit indirectly, oncogenic RAS proteins are druggable by neratinib.