COX-2 inhibitors decrease expression of PD-L1 in colon tumors and increase the influx of Type I tumor infiltrating lymphocytes

Imrecoxib: Advances in Pharmacology and Therapeutics

Imrecoxib, a cyclooxygenase-2 (COX-2) selective non-steroidal anti-inflammatory drug (NSAID), was discovered via the balanced inhibition strategy of COX-1/COX-2. It is indicated for the relief of painful symptoms of osteoarthritis. There have been some pharmacological and therapeutic advances since the approval of imrecoxib in 2011. However, an update review in this aspect is not yet available. Relevant literature until January 2024 was identified by search of PubMed, Web of science, Embase and CNKI. From the perspective of efficacy, imrecoxib provides relief of osteoarthritis symptoms, and potential off-label use for treatment of idiopathic pulmonary fibrosis, perioperative pain, hand-foot syndrome, axial spondyloarthritis, COVID-19, cartilage injury, and malignancies such as lung and colon cancer. From a safety point of view, imrecoxib showed adverse effects common to NSAIDs; however, it has lower incidence of new-onset hypertension than other types of selective COX-2 inhibitors, less gastrointestinal toxicities than non-selective NSAIDs, weaker risk of drug interaction than celecoxib, and more suitable for elderly patients due to balanced inhibition of COX-1/COX-2. From a pharmacoeconomic perspective, imrecoxib is more cost-effective than celecoxib and diclofenac for osteoarthritis patients. With the deepening of the disease pathophysiology study of osteoarthritis, new therapeutic schemes and pharmacological mechanisms are constantly discovered. In the field of osteoarthritis treatment, mechanisms other than the analgesic and anti-inflammatory effects of COX-2 inhibitors are also being explored. Taken together, imrecoxib is a moderate selective COX-2 inhibitor with some advantages, and there would be more clinical applications and research opportunities in the future.

Targeting cyclooxygenase-2 for chemoprevention of inflammation-associated intestinal carcinogenesis: An update

Mounting evidence from preclinical and clinical studies suggests that persistent inflammation functions as a driving force in the journey to cancer. Cyclooxygenase-2 (COX-2) is a key enzyme involved in inflammatory signaling. While being transiently upregulated upon inflammatory stimuli, COX-2 has been found to be consistently overexpressed in human colorectal cancer and several other malignancies. The association between chronic inflammation and cancer has been revisited: cancer can arise when inflammation fails to resolve. Besides its proinflammatory functions, COX-2 also catalyzes the production of pro-resolving as well as anti-inflammatory metabolites from polyunsaturated fatty acids. This may account for the side effects caused by long term use of some COX-2 inhibitory drugs during the cancer chemopreventive trials. This review summarizes the latest findings highlighting the dual functions of COX-2 in the context of its implications in the development, maintenance, and progression of cancer.

Primary Prevention and Interception Studies in RAS-Mutated Tumor Models Employing Small Molecules or Vaccines

Therapeutic targeting of RAS-mutated cancers is difficult, whereas prevention or interception (treatment before or in the presence of preinvasive lesions) preclinically has proven easier. In the A/J mouse lung model, where different carcinogens induce tumors with different KRAS mutations, glucocorticoids and retinoid X receptor (RXR) agonists are effective agents in prevention and interception studies, irrespective of specific KRAS mutations. In rat azoxymethane-induced colon tumors (45% KRAS mutations), cyclooxygenase 1/2 inhibitors and difluoromethylornithine are effective in preventing or intercepting KRAS-mutated or wild-type tumors. In two KRAS-mutant pancreatic models multiple COX 1/2 inhibitors are effective. Furthermore, combining a COX and an EGFR inhibitor prevented the development of virtually all pancreatic tumors in transgenic mice. In the N-nitroso-N-methylurea-induced estrogen receptor-positive rat breast model (50% HRAS mutations) various selective estrogen receptor modulators, aromatase inhibitors, EGFR inhibitors, and RXR agonists are profoundly effective in prevention and interception of tumors with wild-type or mutant HRAS, while the farnesyltransferase inhibitor tipifarnib preferentially inhibits HRAS-mutant breast tumors. Thus, many agents not known to specifically inhibit the RAS pathway, are effective in an organ specific manner in preventing or intercepting RAS-mutated tumors. Finally, we discuss an alternative prevention and interception approach, employing vaccines to target KRAS.

Drug Repurposing to Circumvent Immune Checkpoint Inhibitor Resistance in Cancer Immunotherapy

Immune checkpoint inhibitors (ICI) have achieved unprecedented clinical success in cancer treatment. However, drug resistance to ICI therapy is a major hurdle that prevents cancer patients from responding to the treatment or having durable disease control. Drug repurposing refers to the application of clinically approved drugs, with characterized pharmacological properties and known adverse effect profiles, to new indications. It has also emerged as a promising strategy to overcome drug resistance. In this review, we summarized the latest research about drug repurposing to overcome ICI resistance. Repurposed drugs work by either exerting immunostimulatory activities or abolishing the immunosuppressive tumor microenvironment (TME). Compared to the de novo drug design strategy, they provide novel and affordable treatment options to enhance cancer immunotherapy that can be readily evaluated in the clinic. Biomarkers are exploited to identify the right patient population to benefit from the repurposed drugs and drug combinations. Phenotypic screening of chemical libraries has been conducted to search for T-cell-modifying drugs. Genomics and integrated bioinformatics analysis, artificial intelligence, machine and deep learning approaches are employed to identify novel modulators of the immunosuppressive TME.

Salvia mitiorrhiza Bunge aqueous extract attenuates infiltration of tumor-associated macrophages and potentiates anti-PD-L1 immunotherapy in colorectal cancer through modulating Cox2/PGE2 cascade

ETHNOPHARMACOLOGICAL RELEVANCE

Based on the notion of traditional Chinese medicine, the theory of invigorating the circulation of blood is a prominent treatment for cancer in clinic. Therefore, Salvia miltiorrhiza Bunge, as a representative of Chinese medicine of invigorating the circulation of blood, has been proved to be an effective medicinal herb for treating cancer.

AIM OF THE STUDY

To clarify the anti-cancer effect of Salvia miltiorrhiza Bunge aqueous extract (SMAE) on colorectal cancer (CRC) and investigate whether the therapeutic effect of SMAE was mediated by attenuating the infiltration of tumor-associated macrophages (TAMs) into the tumor microenvironment (TME).

MATERIALS AND METHODS

High-performance liquid chromatography (HPLC) was used for determined the main compounds of SMAE. MC38 cells were subcutaneously injected into the mice to establish the mouse model of CRC. Tumor growth curve was detected by tumor volume measurement. The model group received distilled water irrigation once a day. SMAE-treated group received 5 g/kg or 10 g/kg SMAE once a day. Anti-PD-L1 treated group received 5 mg/kg anti-PD-L1 once every three days. Protein expression of Cox2 and PD-L1 was determined by western blot assay. The secretion levels of PGE2, IL-1β, IL-6, MCP-1, and GM-CSF were evaluated through ELISA. The mRNA expression of CSF1, CCL2, CXCL1, CXCL2, and CXCL3 was measured by using RT-qPCR. Staining of Ki67, TUNEL and Caspase3 was used to investigate cell proliferation and apoptosis. Immunohistochemical staining was used to determine CD8⁺ T cell distribution. H&E staining was used to confirm histopathological changes. The expressions of F4/80 and CD68 were measured by flow cytometry to identify macrophages in tumors and lymph nodes. The number of CD8⁺ T cells and the expression of PD-1, IFN-γ, and Granzyme B (GZMB) were determined by flow cytometry.

RESULTS

SMAE significantly retarded the growth of MC38 mouse colorectal cancer. SMAE strikingly inhibited the expression of Cox2 and impaired the secretion of PGE2 in tumors, contributing to the attenuated intra-tumoral infiltration of TAMs via Cox2/PGE2 cascade. Meanwhile, SMAE augmented anti-tumor immunity by the elevated proportion of IFN-γ⁺ CD8⁺ T cells and GZMB⁺ CD8⁺ T cells, which decreased the tumor load. Furthermore, the combination of SMAE and anti-PD-L1 showed a higher therapeutic efficacy than either monotherapy in controlling tumor growth in MC38 xenograft model.

CONCLUSIONS

SMAE attenuated the infiltration of TAMs into tumors and synergized with anti-PD-L1 to treat CRC via modulating Cox2/PGE2 cascade.

Ketoprofen suppresses triple negative breast cancer cell growth by inducing apoptosis and inhibiting autophagy

BACKGROUND

Triple-negative breast cancer (TNBC) is an invasive phenotype with undesirable clinical features, poor prognosis, and therapy resistance. Ketoprofen is a Non-steroidal anti-inflammatory drug (NSAID) with anti-tumor properties.

AIM

To investigate the effects of Ketoprofen on apoptosis and autophagy in TNBC cell line MDA-MB-231.

METHODS

The cytotoxic activity of Ketoprofen was assayed by the MTS method. Flowcytometry was utilized to measure the number of apoptotic MDA-MB-231 cells. The expression levels of apoptosis and autophagy markers, JAK2 and STAT3 were determined using quantitative real time-PCR (qRT-PCR) and western blotting methods.

RESULTS

Ketoprofen significantly decreased the proliferation of MDA-MB-231 cells compared to control cells. It also considerably induced apoptosis and apoptotic markers in these cells in comparison to controls. Treating the MADA-MB-231 cell line with Ketoprofen had an inhibitory effect on autophagy markers in this cell line. The use of FasL, as a death ligand, and ZB4, as an antibody that blocks the extrinsic pathway of apoptosis, revealed the involvement of the extrinsic pathway in the apoptosis-stimulating effect of Ketoprofen in the MADA-MB-231 cell line. Ketoprofen also hindered the phosphorylation and activation of JAK2 and STAT molecules leading to the inhibition of the JAK/STAT pathway in this TNBC cell line.

CONCLUSION

The outcomes of this study uncovered the anti-TNBC activity of Ketoprofen by inducing apoptosis and inhibiting viability and autophagy in MADA-MB-231 cells. Our data also suggested that Ketoprofen impedes apoptosis in TNBC cells by two different mechanisms including the induction of the extrinsic apoptotic pathway and inhibition of the JAK/STAT signaling.

Lynch syndrome cancer vaccines: A roadmap for the development of precision immunoprevention strategies

Hereditary cancer syndromes (HCS) account for 5~10% of all cancer diagnosis. Lynch syndrome (LS) is one of the most common HCS, caused by germline mutations in the DNA mismatch repair (MMR) genes. Even with prospective cancer surveillance, LS is associated with up to 50% lifetime risk of colorectal, endometrial, and other cancers. While significant progress has been made in the timely identification of germline pathogenic variant carriers and monitoring and early detection of precancerous lesions, cancer-risk reduction strategies are still centered around endoscopic or surgical removal of neoplastic lesions and susceptible organs. Safe and effective cancer prevention strategies are critically needed to improve the life quality and longevity of LS and other HCS carriers. The era of precision oncology driven by recent technological advances in tumor molecular profiling and a better understanding of genetic risk factors has transformed cancer prevention approaches for at-risk individuals, including LS carriers. MMR deficiency leads to the accumulation of insertion and deletion mutations in microsatellites (MS), which are particularly prone to DNA polymerase slippage during DNA replication. Mutations in coding MS give rise to frameshift peptides (FSP) that are recognized by the immune system as neoantigens. Due to clonal evolution, LS tumors share a set of recurrent and predictable FSP neoantigens in the same and in different LS patients. Cancer vaccines composed of commonly recurring FSP neoantigens selected through prediction algorithms have been clinically evaluated in LS carriers and proven safe and immunogenic. Preclinically analogous FSP vaccines have been shown to elicit FSP-directed immune responses and exert tumor-preventive efficacy in murine models of LS. While the immunopreventive efficacy of "off-the-shelf" vaccines consisting of commonly recurring FSP antigens is currently investigated in LS clinical trials, the feasibility and utility of personalized FSP vaccines with individual HLA-restricted epitopes are being explored for more precise targeting. Here, we discuss recent advances in precision cancer immunoprevention approaches, emerging enabling technologies, research gaps, and implementation barriers toward clinical translation of risk-tailored prevention strategies for LS carriers. We will also discuss the feasibility and practicality of next-generation cancer vaccines that are based on personalized immunogenic epitopes for precision cancer immunoprevention.

MDACT: A New Principle of Adjunctive Cancer Treatment Using Combinations of Multiple Repurposed Drugs, with an Example Regimen

In part one of this two-part paper, we present eight principles that we believe must be considered for more effective treatment of the currently incurable cancers. These are addressed by multidrug adjunctive cancer treatment (MDACT), which uses multiple repurposed non-oncology drugs, not primarily to kill malignant cells, but rather to reduce the malignant cells' growth drives. Previous multidrug regimens have used MDACT principles, e.g., the CUSP9v3 glioblastoma treatment. MDACT is an amalgam of (1) the principle that to be effective in stopping a chain of events leading to an undesired outcome, one must break more than one link; (2) the principle of Palmer et al. of achieving fractional cancer cell killing via multiple drugs with independent mechanisms of action; (3) the principle of shaping versus decisive operations, both being required for successful cancer treatment; (4) an idea adapted from Chow et al., of using multiple cytotoxic medicines at low doses; (5) the idea behind CUSP9v3, using many non-oncology CNS-penetrant drugs from general medical practice, repurposed to block tumor survival paths; (6) the concept from chess that every move creates weaknesses and strengths; (7) the principle of mass-by adding force to a given effort, the chances of achieving the goal increase; and (8) the principle of blocking parallel signaling pathways. Part two gives an example MDACT regimen, gMDACT, which uses six repurposed drugs-celecoxib, dapsone, disulfiram, itraconazole, pyrimethamine, and telmisartan-to interfere with growth-driving elements common to cholangiocarcinoma, colon adenocarcinoma, glioblastoma, and non-small-cell lung cancer. gMDACT is another example of-not a replacement for-previous multidrug regimens already in clinical use, such as CUSP9v3. MDACT regimens are designed as adjuvants to be used with cytotoxic drugs.

Role of prostaglandin E2 in the progression of gastrointestinal cancer

Chronic inflammation is a well-established risk factor for several diseases, including cancer. It influences tumor cell biology and the type and density of immune cells in the tumor microenvironment (TME), promoting cancer development. While pro-inflammatory cytokines and chemokines modulate cancer development, emerging evidence has shown that prostaglandin E2 (PGE2) is a known mediator connecting chronic inflammation to cancerization. This review highlights recent advances in our understanding of how the elevation of PGE2 production promotes gastrointestinal cancer initiation, progression, invasion, metastasis, and recurrence, including modulation of immune checkpoint signaling and the type and density of immune cells in the tumor/tissue microenvironment.