Recent Advances in Diagnostic Colonoscopy for Colorectal Cancer Screening: An Update for Radiologists

A hydrogen sulfide-activated Pd@Cu2O nanoprobe for NIR-II photoacoustic imaging of colon cancer and photothermal-enhanced ferroptosis therapy

Imaging guided cancer therapy is a comprehensive strategy that combines the diagnosis and treatment to eradicate tumors. Ferroptosis is a distinct programmed cell death and holds great potential in cancer therapy. In this study, a hydrogen sulfide (H2S)-activated PEGylated Pd@Cu2O core-shell nanocomposite (termed PCO) that in situ transformed into Pd@Cu2-xS (termed PCS) at colorectal tumor tissues is developed for colorectal cancer photoacoustic (PA) imaging and photothermal-enhanced ferroptosis therapy in NIR-II window. The Cu+ on the surface of PCS can catalyze the Fenton-like reaction with overexpressed H2O2 in the colon tumor tissues, yielding hydroxyl radicals (·OH) and Cu2+. Moreover, the PCS accelerates the Fenton-like reaction to generate more ·OH. The PCS displays dual peroxidase- and glutathione oxidase-mimic enzymatic activity in weakly acidic tumor microenvironment (TME). Additionally, the glutathione depletion by Cu2+ results in the production of Cu+ and glutathione disulfide as well as the down-regulation of glutathione peroxidase 4. The interaction of polyunsaturated fatty acids with ·OH induces the up-regulation of lipid peroxides on cellular membrane, thereby causing ferroptosis. Hence, this study has developed the H2S-activated PCO that in situ transforms into PCS, as a novel colon cancer diagnosis-treatment nanoprobe, for PA imaging guided precise diagnosis and efficient therapy of colon cancer.

An intelligent NIR-IIb-responsive lanthanide@metal-organic framework core-shell nanocatalyst for combined deep-tumor therapy

The ground-breaking combination of photodynamic therapy (PDT) and photothermal therapy (PTT) has attracted much attention in medical fields as an effective method for fighting cancer. However, evidence suggests that the therapy efficiency is still limited by shallow light penetration depth and poor photosensitizer loading capacity. Herein, we constructed an upconversion nanoparticle@Zr-based metal-organic framework@indocyanine green molecule (UCNPs@ZrMOF@ICG) nanocomposite to integrate 1532 nm light-triggered PDT and 808 nm light-mediated PTT. NaLnF4 nanoparticles are designed to emit upconversion luminescence (UCL) under 1532 nm laser excitation, which is consistent with the absorption spectra of the ZrMOF. Benefiting from the excellent energy transfer efficiency, the ZrMOF can absorb visible light from the UCNPs and then catalyze O2 into 1O2 for deep tissue PDT. To achieve combination therapy, the clinically approved ICG nanocomposite was introduced as a photothermal agent for PTT under 808 nm laser irradiation, and the photothermal conversion efficiency was calculated to be ∼28%. The designed nanosystems facilitate efficient deep-tissue tumor treatment by integrating PDT with PTT. Ultimately, this study creates a multifunctional nanocomposite by combining 1532 nm light-triggered deep tissue PDT and near-infrared (NIR) light-driven PTT for personalized cancer therapy.

Proteomic screening of potential N-glycoprotein biomarkers for colorectal cancer by TMT labeling combined with LC-MS/MS

BACKGROUND AND AIMS

Colorectal cancer (CRC) is part of the most widespread malignant tumors. At present, colonoscopy is a routine procedure in the diagnosis of CRC, but it is traumatic. Carcinoembryonic antigen, CA199, and CA242 are common serum markers for the diagnosis of CRC; however, they do not demonstrate satisfactory specificity and sensitivity for the diagnosis of CRC. Hence, Now it is necessary to screen many valuable serum biomarkers for CRC, proteomics methods have been used to investigate PTMs such as glycosylation of proteins with prominent roles in the occurrence and development of tumors.

METHODS

This study screens altering glycosylated proteins of CRC tissues using LC-MS/MS quantitative glycoproteomics, and then these candidate biomarkers for CRC are further validated by serum glycoproteomics.

RESULTS

The results of glycoproteomics in CRC tissues show that the abundance of 160 and 79 glycerogelatin proteins was obviously upregulated and downregulated compared with their adjacent tissues(P < 0.05). Bioinformatics analysis suggests that these molecules are mainly involved in many biological processes, including skeletal system development, collagen fibril organization, and receptor-mediated endocytosis. Results of serum glycoproteomics show that the changing trends of 2 protein glycosylation were consistent with MS results of CRC tissues, including ICAM1and APMAP. Areas under the ROC curve (AUC) results confirm that ICAM1and APMAP as early immune diagnosis markers of CRC has excellent sensitivity and specificity.

CONCLUSION

The ICAM1 and APMAP may serve as a potential tumor marker for CRC.

Single-wavelength phototheranostics for colon cancer via the thiolytic reaction

It's a huge challenge to develop effective nanosystems that combine the capabilities of diagnoses and therapies together for colon cancer in the clinic. Herein, we constructed a far-red absorbing phototheranostic nanosystem (FR-H2S) based on the thiolytic reaction of a dinitrophenyl modified phototheranostic prodrug and over-expressed H2S in colon cancer sites for precise imaging-guided phototherapy. FR-H2S with a BODIPY core not only could work as an imaging probe for diagnosis but also act as a phototherapeutic agent for cancer treatment under a single FR laser source (650 nm). FR-H2S exhibited a gradually enhanced fluorescence emission for precise diagnosis of H2S-rich colon tumor sites. After entering tumor cells, FR-H2S could generate abundant 1O2 and heat for phototherapies timely by using the same laser source (650 nm). We believe that this precise imaging-guided phototheranostic nanosystem could provide a promising approach to colon cancer with minimal damage.

Angiopoietin-2 gene polymorphisms are biomarkers for the development and progression of colorectal cancer in Han Chinese

Colorectal cancer (CRC) is one of the most common cancers in Han Chinese and is characterized by low rates of early diagnosis and poor survival rates. Angiopoietin-2 (Ang2), an endothelial tyrosine kinase, is involved in CRC progression, but little is known about the association between single nucleotide polymorphisms (SNPs) and diagnosis or prognosis of CRC. This study reports on the association between 5 SNPs of the Angpt2 gene (rs2442598, rs734701, rs1823375, 11137037, and rs12674822) and CRC susceptibility as well as clinical outcomes in 379 patients with CRC and in 1,043 cancer-free healthy controls. Carriers of the CG allele at rs1823375 and those with the GT+TT allele of the variant rs12674822 were at greater risk of CRC than their respective wild-type counterparts. Moreover, carriers of the GT or GT+TT allele in rs12674822 were significantly more likely to have tumor involvement in both the colon and rectum compared with wild-type (GG) carriers, while 5-year progression-free survival was also significantly worse in those carrying the GT+TT allele in rs12674822 compared with wild-type carriers. Our study is the first to describe correlations between Angpt2 polymorphisms and CRC development and progression in people of Chinese Han ethnicity.

Endogenous H2S-Triggered In Situ Synthesis of NIR-II-Emitting Nanoprobe for In Vivo Intelligently Lighting Up Colorectal Cancer

Overexpression of endogenous H2S is one of the key characteristic in colon cancer. However, developing endogenous H2S-activated optical probes for specific diagnosis of colorectal cancer is rarely explored. Herein, an in situ H2S-activatable second near-infrared (NIR-II)-emitting nanoprobe based on Ag-chicken egg white (Ag-CEW) complex for intelligently lighting up colorectal cancer was explored. The designed Ag-CEW complex holds efficient NIR-II emission of 1,000-1,400 nm via endogenous H2S-induced in situ chemical reaction to form Ag2S quantum dots (QDs). After reaction, the designed Ag-CEW complex with high photo-stability and biocompatibility was successfully used for NIR-II imaging-guided specific visualization and precise location of colorectal cancer via endogenous H2S activation. Therefore, our findings provide a new route for specifically targeting diagnosis of colon cancer based on the in situ-activatable NIR-II probe.

Smart nanomedicine agents for cancer, triggered by pH, glutathione, H2O2, or H2S

Effective tumor diagnosis and therapy have always been a significant but challenging issue. Although nanomedicine has shown great potential for improving the outcomes of tumor diagnosis and therapy, the nonspecial targeted distribution of nanomedicine agents in the whole body causes a low diagnosis signal-to-noise ratio and a potential risk of systemic toxicity. Recently, the development of smart nanomedicine agents with diagnosis and therapy functions that can only be activated by the tumor microenvironment (TME) is regarded as an effective strategy to improve the theranostic sensitivity and selectivity, as well as reduce the potential side effects during treatment. This article will introduce and summarize the latest achievements in the design and fabrication of TME-responsive smart nanomedicine agents, and highlight their prospects for enhancing tumor diagnosis and therapy.

The Natural History of Colorectal Polyps: Overview of Predictive Static and Dynamic Features

For decades, colorectal screening strategies have been largely driven by static features, particularly polyp size. Although cross-sectional features of polyp size, morphology, and location are important determinants of clinical relevance before histology, they lack any dynamic information on polyp growth rates. Computed tomography colonography allows for in vivo surveillance of colorectal polyps, providing volumetric growth rates that are providing new insights into tumorigenesis. In this article, existing cross-sectional and longitudinal data on colorectal polyps are reviewed, with an emphasis on how these features may affect clinical relevance and patient management.