A personalized and long-acting local therapeutic platform combining photothermal therapy and chemotherapy for the treatment of multidrug-resistant colon tumor

Revisiting the smart metallic nanomaterials: advances in nanotechnology-based antimicrobials

Despite significant advancements in diagnostics and treatments over the years, the problem of antimicrobial drug resistance remains a pressing issue in public health. The reduced effectiveness of existing antimicrobial drugs has prompted efforts to seek alternative treatments for microbial pathogens or develop new drug candidates. Interestingly, nanomaterials are currently gaining global attention as a possible next-generation antibiotics. Nanotechnology holds significant importance, particularly when addressing infections caused by multi-drug-resistant organisms. Alternatively, these biomaterials can also be combined with antibiotics and other potent biomaterials, providing excellent synergistic effects. Over the past two decades, nanoparticles have gained significant attention among research communities. Despite the complexity of some of their synthesis strategies and chemistry, unrelenting efforts have been recorded in synthesizing potent and highly effective nanomaterials using different approaches. With the ongoing advancements in nanotechnology, integrating it into medical procedures presents novel approaches for improving the standard of patient healthcare. Although the field of nanotechnology offers promises, much remains to be learned to overcome the several inherent issues limiting their full translation to clinics. Here, we comprehensively discussed nanotechnology-based materials, focusing exclusively on metallic nanomaterials and highlighting the advances in their synthesis, chemistry, and mechanisms of action against bacterial pathogens. Importantly, we delve into the current challenges and prospects associated with the technology.

Nanotechnology-based delivery systems to overcome drug resistance in cancer

Cancer nanomedicine is defined as the application of nanotechnology and nanomaterials for the formulation of cancer therapeutics that can overcome the impediments and restrictions of traditional chemotherapeutics. Multidrug resistance (MDR) in cancer cells can be defined as a decrease or abrogation in the efficacy of anticancer drugs that have different molecular structures and mechanisms of action and is one of the primary causes of therapeutic failure. There have been successes in the development of cancer nanomedicine to overcome MDR; however, relatively few of these formulations have been approved by the United States Food and Drug Administration for the treatment of cancer. This is primarily due to the paucity of knowledge about nanotechnology and the fundamental biology of cancer cells. Here, we discuss the advances, types of nanomedicines, and the challenges regarding the translation of in vitro to in vivo results and their relevance to effective therapies.

Injectable hydrogels for the delivery of nanomaterials for cancer combinatorial photothermal therapy

Progress in the nanotechnology field has led to the development of a new class of materials capable of producing a temperature increase triggered by near infrared light. These photothermal nanostructures have been extensively explored in the ablation of cancer cells. Nevertheless, the available data in the literature have exposed that systemically administered nanomaterials have a poor tumor-homing capacity, hindering their full therapeutic potential. This paradigm shift has propelled the development of new injectable hydrogels for the local delivery of nanomaterials aimed at cancer photothermal therapy. These hydrogels can be assembled at the tumor site after injection (in situ forming) or can undergo a gel-sol-gel transition during injection (shear-thinning/self-healing). Besides incorporating photothermal nanostructures, these injectable hydrogels can also incorporate or be combined with other agents, paving the way for an improved therapeutic outcome. This review analyses the application of injectable hydrogels for the local delivery of nanomaterials aimed at cancer photothermal therapy as well as their combination with photodynamic-, chemo-, immuno- and radio-therapies.

Poly Ethylene Glycol (PEG)-Based Hydrogels for Drug Delivery in Cancer Therapy: A Comprehensive Review

Hydrogel-based drug delivery systems (DDSs) can leverage therapeutically beneficial outcomes in cancer therapy. In this domain, polyethylene glycol (PEG) has become increasingly popular as a biomedical polymer and has found clinical use. Owing to their excellent biocompatibility, facile modifiability, and high drug encapsulation rate, PEG hydrogels have shown great promise as drug delivery platforms. Here, the progress in emerging novel designs of PEG-hydrogels as DDSs for anti-cancer therapy is reviewed and discussed, focusing on underpinning multiscale release mechanisms categorized under stimuli-responsive and non-responsive drug release. The responsive drug delivery approaches are discussed, and the underpinning release mechanisms are elucidated, covering the systems functioning based on either exogenous stimuli-response, such as photo- and magnetic-sensitive PEG hydrogels, or endogenous stimuli-response, such as enzyme-, pH-, reduction-, and temperature-sensitive PEG hydrogels. Special attention is paid to the commercial potential of PEG-based hydrogels in cancer therapy, highlighting the limitations that need to be addressed in future research for their clinical translation.

Enzyme-catalyzed synthesis of selenium-doped manganese phosphate for synergistic therapy of drug-resistant colorectal cancer

BACKGROUND

The development of multidrug resistance (MDR) during postoperative chemotherapy for colorectal cancer substantially reduces therapeutic efficacy. Nanostructured drug delivery systems (NDDSs) with modifiable chemical properties are considered promising candidates as therapies for reversing MDR in colorectal cancer cells. Selenium-doped manganese phosphate (Se-MnP) nanoparticles (NPs) that can reverse drug resistance through sustained release of selenium have the potential to improve the chemotherapy effect of colorectal cancer.

RESULTS

Se-MnP NPs had an organic-inorganic hybrid composition and were assembled from smaller-scale nanoclusters. Se-MnP NPs induced excessive ROS production via Se-mediated activation of the STAT3/JNK pathway and a Fenton-like reaction due to the presence of manganese ions (Mn²⁺). Moreover, in vitro and in vivo studies demonstrated Se-MnP NPs were effective drug carriers of oxaliplatin (OX) and reversed multidrug resistance and induced caspase-mediated apoptosis in colorectal cancer cells. OX@Se-MnP NPs reversed MDR in colorectal cancer by down-regulating the expression of MDR-related ABC (ATP binding cassette) transporters proteins (e.g., ABCB1, ABCC1 and ABCG2). Finally, in vivo studies demonstrated that OX-loaded Se-MnP NPs significantly inhibited proliferation of OX-resistant HCT116 (HCT116/DR) tumor cells in nude mice.

CONCLUSIONS

OX@Se-MnP NPs with simple preparation and biomimetic chemical properties represent promising candidates for the treatment of colorectal cancer with MDR.

The Controlled Release and Prevention of Abdominal Adhesion of Tannic Acid and Mitomycin C-Loaded Thermosensitive Gel

Postoperative abdominal adhesion is one of the most common complications after abdominal surgery. A single drug or physical barrier treatment does not achieve the ideal anti-adhesion effect. We developed a thermosensitive hydrogel (PPH hydrogel) consisting of poloxamer 407 (P407), poloxamer (P188), and hydroxypropyl methylcellulose (HPMC) co-blended. An injectable thermosensitive TA/MMC-PPH hydrogel was obtained by loading tannic acid (TA) with an anti-inflammatory effect and mitomycin C (MMC), which inhibits fibroblast migration or proliferation. The optimal prescriptions of PPH hydrogels with a suitable gelling time (63 s) at 37 °C was 20% (w/v) P407, 18% (w/v) P188, and 0.5% (w/v) HPMC. The scanning electron microscopy (SEM) revealed that the PPH hydrogel had a three-dimensional mesh structure, which was favorable for drug encapsulation. The PPH hydrogel had a suitable gelation temperature of 33 °C, a high gel strength, and complicated viscosity at 37 °C, according to the rheological analysis. In vitro release studies have shown that the PPH hydrogel could delay the release of TA and MMC and conform to the first-order release rate. Anti-adhesion tests performed on rats in vivo revealed that TA/MMC-PPH hydrogel significantly reduced the risk of postoperative adhesion. In conclusion, the TA/MMC-PPH hydrogel prepared in this study showed an excellent performance in both controlled drug release and anti-adhesive effects. It can be used as a protocol to prevent or reduce postoperative abdominal adhesion.

Novel strategies to reverse chemoresistance in colorectal cancer

Colorectal cancer (CRC) is a common gastrointestinal malignancy with high morbidity and fatality. Chemotherapy, as traditional therapy for CRC, has exerted well antitumor effect and greatly improved the survival of CRC patients. Nevertheless, chemoresistance is one of the major problems during chemotherapy for CRC and significantly limits the efficacy of the treatment and influences the prognosis of patients. To overcome chemoresistance in CRC, many strategies are being investigated. Here, we review the common and novel measures to combat the resistance, including drug repurposing (nonsteroidal anti-inflammatory drugs, metformin, dichloroacetate, enalapril, ivermectin, bazedoxifene, melatonin, and S-adenosylmethionine), gene therapy (ribozymes, RNAi, CRISPR/Cas9, epigenetic therapy, antisense oligonucleotides, and noncoding RNAs), protein inhibitor (EFGR inhibitor, S1PR2 inhibitor, and DNA methyltransferase inhibitor), natural herbal compounds (polyphenols, terpenoids, quinones, alkaloids, and sterols), new drug delivery system (nanocarriers, liposomes, exosomes, and hydrogels), and combination therapy. These common or novel strategies for the reversal of chemoresistance promise to improve the treatment of CRC.

Multifunctional Gold Nanoparticles in Cancer Diagnosis and Treatment

Cancer is the second leading cause of death in the world, behind only cardiovascular diseases, and is one of the most serious diseases threatening human health nowadays. Cancer patients’ lives are being extended by the use of contemporary medical technologies, such as surgery, radiotherapy, and chemotherapy. However, these treatments are not always effective in extending cancer patients’ lives. Simultaneously, these approaches are often accompanied with a series of negative consequences, such as the occurrence of adverse effects and an increased risk of relapse. As a result, the development of a novel cancer-eradication strategy is still required. The emergence of nanomedicine as a promising technology brings a new avenue for the circumvention of limitations of conventional cancer therapies. Gold nanoparticles (AuNPs), in particular, have garnered extensive attention due to their many specific advantages, including customizable size and shape, multiple and useful physicochemical properties, and ease of functionalization. Based on these characteristics, many therapeutic and diagnostic applications of AuNPs have been exploited, particularly for malignant tumors, such as drug and nucleic acid delivery, photodynamic therapy, photothermal therapy, and X-ray-based computed tomography imaging. To leverage the potential of AuNPs, these applications demand a comprehensive and in-depth overview. As a result, we discussed current achievements in AuNPs in anticancer applications in a more methodical manner in this review. Also addressed in depth are the present status of clinical trials, as well as the difficulties that may be encountered when translating some basic findings into the clinic, in order to serve as a reference for future studies.

Emerging trends in the application of gold nanoformulations in colon cancer diagnosis and treatment

Colorectal cancer is one of the most aggressive types of cancer with about two million new cases and one million deaths in 2020. The side effects of the available chemotherapies and the possibility of developing resistance against treatment highlight the importance of developing new therapeutic options. The development in the field of nanotechnology have introduced the application of nanoparticles (NPs) as a promising approach in the diagnosis and treatments of colorectal cancer and other types of cancer. Gold nanoparticles (AuNPs) are currently one of the most studied materials as they possess unique tunable properties allowing them to play a role in colorectal cancer bioimaging, diagnosis, and therapy. The high surface-to-volume ratio of AuNPs mediates their utilization in drug delivery as well as functionalization to provide specific targeting. Moreover, depending on their physical properties (size, shape), AuNPs can be modified to fit the intended application. However, there are contradictory results around the pharmacokinetics of AuNPs including their biodistribution, clearance, and toxicity. This variation of opinions is most likely due to the development of different AuNPs that vary in shape, size, and surface chemistry, in addition to the conditions under which each research was carried out. The conflicting data represent a challenge in the clinical use of AuNPs suggesting the need to understand the toxicity, fate, and long-term exposure of AuNPs in vivo. Thus, there is an unmet need for the establishment of a publicly available data base for extensive analysis. In this review, we discuss the recent advances in AuNP applications in the treatment and diagnosis of colorectal cancer, mechanisms of action, and clinical challenges.

Progress in the study of D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) reversing multidrug resistance

Currently, multidrug resistance (MDR) is one of the major reasons for failure in clinical cancer chemotherapy. Overexpression of the ATP binding cassette (ABC) transporter P-glycoprotein (P-gp), which significantly increases the efflux of anticancer drugs from tumor cells, enhances MDR. In the past few decades, four generations of P-gp inhibitors have appeared. However, they are limited in clinical application due to their severe toxic side effects. As a P-gp inhibitor and carrier for loading chemotherapy agents, TPGS has received increasing attention due to its advantages and unique properties of reversing MDR. TPGS is an amphipathic agent that increases the solubility of most chemotherapy drugs and decreases severe side effects. In addition, TPGS is an excellent carrier with P-gp-inhibiting ability. In this review, we summarize the latest articles on TPGS-based nanodelivery systems to prevent MDR.

Nanomedicine to Overcome Multidrug Resistance Mechanisms in Colon and Pancreatic Cancer: Recent Progress

The development of drug resistance is one of the main causes of cancer treatment failure. This phenomenon occurs very frequently in different types of cancer, including colon and pancreatic cancers. However, the underlying molecular mechanisms are not fully understood. In recent years, nanomedicine has improved the delivery and efficacy of drugs, and has decreased their side effects. In addition, it has allowed to design drugs capable of avoiding certain resistance mechanisms of tumors. In this article, we review the main resistance mechanisms in colon and pancreatic cancers, along with the most relevant strategies offered by nanodrugs to overcome this obstacle. These strategies include the inhibition of efflux pumps, the use of specific targets, the development of nanomedicines affecting the environment of cancer-specific tissues, the modulation of DNA repair mechanisms or RNA (miRNA), and specific approaches to damage cancer stem cells, among others. This review aims to illustrate how advanced nanoformulations, including polymeric conjugates, micelles, dendrimers, liposomes, metallic and carbon-based nanoparticles, are allowing to overcome one of the main limitations in the treatment of colon and pancreatic cancers. The future development of nanomedicine opens new horizons for cancer treatment.

Advances and trends of hydrogel therapy platform in localized tumor treatment: A review

Due to limitations of treatment and the stubbornness of infiltrative tumor cells, the outcome of conventional antitumor treatment is often compromised by a variety of factors, including severe side effects, unexpected recurrence, and massive tissue loss during the treatment. Hydrogel-based therapy is becoming a promising option of cancer treatment, because of its controllability, biocompatibility, high drug loading, prolonged drug release, and specific stimuli-sensitivity. Hydrogel-based therapy has good malleability and can reach some areas that cannot be easily touched by surgeons. Furthermore, hydrogel can be used not only as a carrier for tumor treatment agents, but also as a scaffold for tissue repair. In this review, we presented the latest researches in hydrogel applications of localized tumor therapy and highlighted the recent progress of hydrogel-based therapy in preventing postoperative tumor recurrence and improving tissue repair, thus proposing a new trend of hydrogel-based technology in localized tumor therapy. And this review aims to provide a novel reference and inspire thoughts for a more accurate and individualized cancer treatment.

Laser-triggered collaborative chemophotothermal effect of gold nanoparticles for targeted colon cancer therapy

Nanotechnology has shown advantages for cancer treatment. Multimodal nanoparticles (NPs) combining chemotherapy and photothermal therapy are promising and elicit synergetic benefit. However, there were still less multifunctional nanomaterials with good targeting and anti-tumor property applied as the colon cancer therapeutic strategy. In this study, we designed the gold NPs modified with AS1411 and DNA riched of GC intercalation (hairpin DNA) with doxorubicin (DOX) for targeted chemotherapy and NIR laser-triggered chemo-photothermal effect (PTT). We took advantage of PTT effect to realize DOX release from hairpin DNA. We also demonstrated AS1411 based NPs exhibited remarkable targeted binding towards SW480 colon cancer cells in vitro and enhanced uptake inside the cells. Strikingly, AS1411 based NPs exhibited the most efficient cytotoxicity and markedly enhanced inhibition effect on cells proliferation to SW480 cells under laser exposure when compared to the NPs merely with PTT or chemotherapy. Our study appears to provide an alternative nanoplatform with good targeted and chemo-photothermal therapy against colon cancer.

Nanoparticles in Colorectal Cancer Therapy: Latest In Vivo Assays, Clinical Trials, and Patents

Colorectal cancer (CRC) is the third most common cancer worldwide. Its poor response to current treatment options in advanced stages and the need for efficient diagnosis in early stages call for the development of new therapeutic and diagnostic strategies. Some of them are based on the use of nanometric materials as carriers and releasers of therapeutic agents and fluorescent molecules, or even on the utilization of magnetic materials that provide very interesting properties. These nanoformulations present several advantages compared with the free molecular cargo, including increased drug solubility, bioavailability, stability, and tumor specificity. Moreover, tumor multidrug resistance has been decreased in some cases, leading to improved treatment effectiveness by reducing drug dose and potential side effects. Here, we present an updated overview of the latest advances in clinical research, in vivo studies, and patents regarding the application of nanoformulations in the treatment of CRC. Based on the information gathered, a wide variety of nanomaterials are being investigated in clinical research, even in advanced phases, i.e., close to reaching the market. In sum, these novel materials can offer remarkable advantages with respect to current therapies, which could be complemented or even replaced by these nanosystems in the near future.

CMTM4 inhibits cell proliferation and migration via AKT, ERK1/2, and STAT3 pathway in colorectal cancer

CMTM4 (CKLF-like MARVEL transmembrane domain containing 4), a potential tumor suppressor gene, is involved in several types of malignancies. It has been reported to be downregulated and exhibit anti-tumorigenic activities by regulating cell growth and cell cycle in clear cell renal cell carcinoma. It has also been identified as a tumor suppressor in hepatocellular carcinoma (HCC), and its negative expression is a risk factor for poor prognosis of HCC patients. In the present study, an integrated bioinformatics analysis based on The Cancer Genome Atlas (TCGA) database showed that CMTM4 was frequently reduced in colorectal cancer (CRC) and high expression of CMTM4 was associated with increased overall survival rates. Based on these findings, we adopted gain-of-function and lost-of-function strategies using SW480 and HT29 CRC cell lines which have relatively low and high endogenous CMTM4 levels, respectively. We observed impeded cell proliferation and migration upon overexpression of CMTM4 in SW480 cells, and the opposite effects were observed upon knockdown of CMTM4 in HT-29 cells. Cell signaling pathways essential for CRC progression were then examined, and the phosphorylation levels of AKT, ERK1/2, and STAT3 were found to be decreased by CMTM4 overexpression in SW480 cells and elevated by CMTM4 silencing in HT29 cells. Their inhibitors were used to validate that the three signaling pathways contributed to the inhibitory effects of CMTM4 on CRC cells. Taken together, our results suggest that CMTM4 plays a tumor suppressive role in CRC.

Gold as a Possible Alternative to Platinum-Based Chemotherapy for Colon Cancer Treatment

Due to the increasing incidence and high mortality associated with colorectal cancer (CRC), novel therapeutic strategies are urgently needed. Classic chemotherapy against CRC is based on oxaliplatin and other cisplatin analogues; however, platinum-based therapy lacks selectivity to cancer cells and leads to deleterious side effects. In addition, tumor resistance to oxaliplatin is related to chemotherapy failure. Gold(I) derivatives are a promising alternative to platinum complexes, since instead of interacting with DNA, they target proteins overexpressed on tumor cells, thus leading to less side effects than, but a comparable antitumor effect to, platinum derivatives. Moreover, given the huge potential of gold nanoparticles, the role of gold in CRC chemotherapy is not limited to gold(I) complexes. Gold nanoparticles have been found to be able to overcome multidrug resistance along with reduced side effects due to a more efficient uptake of classic drugs. Moreover, the use of gold nanoparticles has enhanced the effect of traditional therapies such as radiotherapy, photothermal therapy, or photodynamic therapy, and has displayed a potential role in diagnosis as a consequence of their optic properties. Herein, we have reviewed the most recent advances in the use of gold(I) derivatives and gold nanoparticles in CRC therapy.