Estrogen receptor β affects hypoxia response in colorectal cancer cells

The occurrence of colorectal cancer (CRC) is inversely correlated with estrogen receptor beta (ERβ) presence. Additionally, multiple studies associate low ERβ expression with poorer overall survival of CRC patients. Molecular pathways involved in ERβ - related reduced tumorigenesis include enhanced apoptosis, decreased proliferation, or repression of oncogenes. Moreover, the development of solid tumors, such as CRC, is often associated with an increased tumor mass that results in decreased oxygen partial tension, known as hypoxia, clinically associated with decreased prognosis and therapeutic resistance. Our high-throughput study suggests that ERβ also represses a hypoxic response in CRC cells. We observed a significantly altered transcriptional profile in HCT116 ERβ overexpressing cells that was further stimulated by E2 treatment under hypoxic conditions. The achieved data for downregulation of VEGFA, PDGFA and ANGPTL4 were validated in a time course experiment in DLD-1 cells. In addition, using an ERβ construct with a mutated DNA binding domain we observed that the downregulation of selected genes is dependent on the direct binding of this receptor to regulatory region genes. In addition, we observed that ERβ may affect the expression of the main hypoxia regulator, HIF1A, at the transcriptional and translational levels. In summary, ERβ alters the hypoxic outcome in CRC cells.

KLF4 targets RAB26 and decreases 5-FU resistance through inhibiting autophagy in colon cancer

BACKGROUND

Accumulating studies demonstrated that resistance of colon cancer (CC) to 5-fluorouracil (5-FU) contributes to adverse prognosis. We investigated how Kruppel-like factor 4 (KLF4) affected 5-FU resistance and autophagy in CC cells.

METHODS

KLF4 expression and its downstream target gene RAB26 in CC tissues was analyzed by bioinformatics analysis, and the effect of abnormal KLF4 expression on prognoses of CC patients was predicted. Luciferase reporter assay detected the targeted relationship between KLF4 and RAB26. The viability and apoptosis of CC cells were analyzed by CCK-8 and flow cytometry. The formation of intracellular autophagosomes was detected by confocal laser scanning microscopy and immunofluorescence staining. The mRNA and protein levels were assayed by qRT-PCR and western blot. A xenograft animal model was constructed to verify the function of KLF4. Rescue assay was employed to verify whether KLF4/RAB26 could affect 5-FU resistance in CC cells through autophagy.

RESULTS

KLF4 and RAB26 were lowly expressed in CC. KLF4 correlated with patients' survival. KLF4 was down-regulated in 5-FU resistant CC cells. KLF4 overexpression suppressed the proliferation and 5-FU resistance of CC cells, and inhibited LC3 II/I expression and autophagosome formation. Autophagy activator Rapamycin or sh-RAB26 treatment reversed the impact of KLF4 overexpression on 5-FU resistance. In vivo assay verified that KLF4 inhibited 5-FU resistance in CC cells. Rescue experiments revealed that KLF4 targeted RAB26 to inhibit CC cell autophagy, resulting in decreasing the resistance to 5-FU.

CONCLUSION

KLF4 strengthened the sensitivity of CC cells to 5-FU by targeting RAB26 to restrain autophagy pathway.

Box Behnken optimization of cubosomes for enhancing the anticancer activity of metformin: Design, characterization, and in-vitro cell proliferation assay on MDA-MB-231 breast and LOVO colon cancer cell lines

This study aimed to formulate and statistically optimize cubosomal formulations of metformin (MTF) to enhance its breast anticancer activity. A Box Behnken design was employed using Design-Expert® software. The formulation variables were glyceryl monooleate concentration (GMO) w/w%, Pluronic F-127 concentration (PF127) w/w% and Tween 80 concentration w/w% whereas Entrapment efficiency (EE%), Vesicles' size (VS) and Zeta potential (ZP) were set as the dependent responses. The design expert software was used to perform the process of optimization numerically. X ray diffraction (XRD), Transmission electron microscope (TEM), in-vitro release study, short-term stability study, and in in-vitro cell proliferation assay on the MDA-MB-231 breast cancer and LOVO cancer cell lines were used to validate the optimized cubosomal formulation. The optimized formulation had a composition of 4.35616 (w/w%) GMO, 5 (w/w%) PF127 and 7.444E-6 (w/w%) Tween 80 with a desirability of 0.733. The predicted values for EE%, VS and ZP were 78.0592%, 307.273 nm and - 26.8275 mV, respectively. The validation process carried out on the optimized formula revealed that there were less than a 5% variance from the predicted responses. The XRD thermograms showed that MTF was encapsulated inside the cubosomal vesicles. TEM images of the optimized MTF cubosomal formulation showed spherical non-aggregated nanovesicles. Moreover, it revealed a sustained release profile of MTF in comparison to the MTF solution. Stability studies indicated that optimum cubosomal formulation was stable for thirty days. Cytotoxicity of the optimized cubosomal formulation was enhanced on the MDA-MB-231 breast and LOVO cancer cell lines compared to MTF solution even at lower concentrations. However, it showed superior cytotoxic effect on breast cancer cell line. So, cubosomes could be considered a promising carrier of MTF to treat breast and colon cancers.

WTAP regulates autophagy in colon cancer cells by inhibiting FLNA through N6-methyladenosine

Our study investigated the role of WTAP in colon cancer. We employed experiments including m6A dot blot hybridization, methylated RNA immunoprecipitation, dual-luciferase, and RNA immunoprecipitation to investigate the regulatory mechanism of WTAP. Western blot was performed to analyze the expression of WTAP, FLNA and autophagy-related proteins in cells. Our results confirmed the up-regulation of WTAP in colon cancer and its promoting effect on proliferation and inhibiting effect on apoptosis. FLNA was the downstream gene of WTAP and WTAP-regulated m6A modification led to post-transcriptional repression of FLNA. The rescue experiments showed that WTAP/FLNA could inhibit autophagy. WTAP-mediated m6A modification was confirmed to be crucial in colon cancer development, providing new insights into colon cancer therapy.

Discovery of potent heat shock protein 90 (Hsp90) inhibitors: structure-based virtual screening, molecular dynamics simulation, and biological evaluation

Heat shock protein 90 (Hsp90) is considered an attractive therapeutic target for cancer treatment due to its high expression in many cancers. In this study, four potent Hsp90 inhibitors (HPs 1-4) were identified using structure-based virtual screening. Among them, HP-4 exhibited the most potent inhibitory effects (IC₅₀ = 17.64 ± 1.45 nM) against the Hsp90 protein, which was about 7.7 times stronger than that of MPC-3100 (a positive inhibitor targeting Hsp90). In vitro cytotoxicity assay suggested that HP-4 could effectively inhibit the proliferation of a series of tumour cells, including HCT-116, HeLa, A549, A2780, DU145, HepG2 and A498. Furthermore, in vivo assay displayed that HP-4 had significant anti-tumour effects on HCT-116 cell-derived xenograft models. These data demonstrate that HP-4 could be a potential lead compound for the further investigation of anti-tumour drugs.

Elevated colorectal cancer incidence among American Indian/Alaska native persons in Alaska compared to other populations worldwide

Colorectal cancer (CRC) is a leading cancer worldwide; incidence varies greatly by country and racial group. We compared 2018 American Indian/Alaska Native (AI/AN) CRC incidence rates in Alaska to other Tribal, racial, and international population rates. AI/AN persons in Alaska had the highest CRC incidence rate among US Tribal and racial groups (61.9/100,000 in 2018). AI/AN persons in Alaska also had higher rates than those reported for any other country in the world in 2018 except for Hungary, where males had a higher CRC incidence rate than AI/AN males in Alaska (70.6/100,000 and 63.6/100,000 respectively). This review of CRC incidence rates from populations in the United States and worldwide showed that AI/AN persons in Alaska had the highest documented incidence rate of CRC in the world in 2018. It is important to inform health systems serving AI/AN persons in Alaska about policies and interventions that can support CRC screening to reduce the burden of this disease.

Opium use and risk of colorectal cancer: a multi-center case-referent study in Iran

BACKGROUND

Opium use has been associated with an increased risk of cancers of the lung, oesophagus, and pancreas, and it was recently classified by the International Agency for Cancer Research as carcinogenic to humans. It is not clear whether opium also increases the risk of colorectal cancer (CRC). The aim of our study was to assess the association between various metrics of opium use and the risk of CRC.

METHODS

This case-referent study from seven provinces in Iran comprised 848 CRC cases and 3215 referents. Data on opium use (duration, amount, frequency) and potential confounders were collected by trained interviewers. Multivariable unconditional logistic regression models were used to measure odds ratios (OR) adjusted for age, gender, province, marital status, family history of CRC-linked cancers, consumption of red meat, fruits and vegetables, body shape, occupational physical activity, and socioeconomic status.

RESULTS

Regular opium consumption was not associated with the risk of CRC (OR 0.9, 95% confidence interval, CI: 0.7, 1.2) compared to subjects who never used opium. However, frequent opium use more than twice a day was associated with an increased risk of CRC compared to non-users of opium (OR: 2.0, 95% CI: 1.1, 3.8; p for quadratic trend 0.008).

CONCLUSION

There seems to be no overall association between opium use and CRC, but the risk of CRC might be increased among persons who use opium many times a day.

Age as a modifier of the effects of sarcopenia on survival among colon cancer patients after surgery

BACKGROUND

Studies have been conducted to evaluate whether sarcopenia is a predictor for survival in patients with colon cancer postsurgery, but findings have been inconsistent, and effects of age were seldom evaluated.

METHODS

We recruited 133 patients with resectable colon cancer who underwent surgery between January 2014 and December 2017 at a teaching hospital to evaluate the effects of sarcopenia on survival, after adjusting for age and other potential predictors, including visceral adiposity (VA).

RESULTS

Preoperative sarcopenia was associated with worse overall survival (OS: 62.3% vs. 83.8%, p = 0.04) and longer hospital stay (20.6 vs. 14.9 days, p < 0.01) while VA was not. Cox proportional hazards regressions showed that sarcopenia was associated with an adjusted hazard ratio (HR) of 2.91 (95% confidence interval [CI]: 1.08-7.86) after adjustment for other independent risk factors, but was not associated with disease free survival. In stratified analyses, we found that sarcopenia was an independent factor for worse OS (adjusted HR = 1.94; 95% CI: 1.11-3.38) among patients >70 years, but not among patients ≤70 years (HR = 0.48; 95% CI: 0.55-4.55).

CONCLUSIONS

Age appeared to be a modifier of the effects of sarcopenia on OS among colon cancer patients postsurgery.

Anti-inflammatory mechanisms in cancer research: Characterization of a distinct M2-like macrophage model derived from the THP-1 cell line

AIMS

Macrophages play an essential role in cancer development. Tumor-associated macrophages (TAMs) have predominantly M2-like attributes that are associated with tumor progression and poor patient survival. Numerous methods have been reported for differentiating and polarizing macrophages in vitro, but there is no standardized and validated model for creating TAMs. Primary cells show varying cytokine responses depending on their origin and functional studies utilizing these cells may lack generalization and validity. A distinct cell line-derived TAM-like M2 subtype is required to investigate the mechanisms mediated by anti-inflammatory TAMs in vitro. Our previous work demonstrated a standardized protocol for creating an M2 subtype derived from a human THP-1 cell line. The cell expression profile, however, has not been validated. The aim of this study was to characterize and validate the TAM-like M2 subtype macrophage created based on our protocol to introduce them as a standardized model for cancer research.

METHODS AND RESULTS

Using qRT-PCR and ELISA, we demonstrated that proinflammatory, anti-inflammatory, and tumor-associated marker expression changed during THP-1-derived marcrophage development in vitro, mimicking a TAM-related profile (e.g., TNFα, IL-1β). The anti-inflammatory marker IL-8/CXCL8, however, is most highly expressed in young M0 macrophages. Flow cytometry showed increased expression of CD206 in the final TAM-like M2 macrophage. Single-cell RNA-sequencing analysis of primary human monocytes and colon cancer tissue macrophages demonstrated that cell line-derived M2 macrophages resembled a TAM-related gene profile.

CONCLUSIONS

The THP-1-derived M2 macrophage based on a standardized cell line model represents a distinct anti-inflammatory TAM-like phenotype with an M2a subtype profile. This model may provide a basis for in vitro investigation of functional mechanisms in a variety of anti-inflammatory settings, particularly colon cancer development.

Chemotherapy reduces long-term quality of life in recurrence-free colon cancer survivors (LaTE study)-a nationwide inverse probability of treatment-weighted registry-based cohort study and survey

AIM

Stage III colon cancer is routinely treated with adjuvant chemotherapy, which causes significant short-term morbidity. Its effect on long-term quality of life (QoL) is poorly investigated. The aim of this study was to investigate long-term QoL after curative treatment for colon cancer and explore the impact of chemotherapy on general and disease-specific QoL.

METHOD

All patients aged under 75 years operated on for colon cancer between 30 September 2007 and 1 October 2019 were identified by the Cancer Registry of Norway. Exclusion criteria were distant metastasis, recurrence, dementia and rectal/rectosigmoid cancer operation. The primary outcome measure was Gastrointestinal Quality of Life Index (GIQLI). Secondary outcome measures included the Short Form Health Survey (SF-36). To achieve balanced groups when assessing differences in outcome measures the analyses were weighted by inverse probability weights based on a multiple logistic regression model with prechosen confounders.

RESULTS

A total of 8627 patients were invited and 3109 responded (36% response rate). After exclusions 3025 patients were included, of whom 1148 (38%) had received adjuvant chemotherapy and 1877 (62%) had surgery alone, with mean follow-up of 75.5 versus 74.5 months, respectively. The GIQLI differed significantly between the groups [mean 111.0 (SD 18.4) vs. 115.6 (SD 17.8), respectively; mean difference: -4.6 (95% CI -5.9; -3.2); p < 0.001]. Those with the highest neurotoxicity exhibited the lowest GIQLI. The adjuvant chemotherapy group scored significantly lower in six of eight SF-36 domains compared with the surgery alone group. The main differences were found in social, physical and emotional function.

CONCLUSION

Long-term QoL was significantly lower in patients who received adjuvant chemotherapy than in patients who did not. Neurotoxicity was closely related to reduced QoL in these patients. The low response rate limits the generalizability of the results.

Mapping and modeling human colorectal carcinoma interactions with the tumor microenvironment

The initiation and progression of cancer are intricately linked to the tumor microenvironment (TME). Understanding the function of specific cancer-TME interactions poses a major challenge due in part to the complexity of the in vivo microenvironment. Here we predict cancer-TME interactions from single cell transcriptomic maps of both human colorectal cancers (CRCs) and mouse CRC models, ask how these interactions are altered in human tumor organoid (tumoroid) cultures, and functionally recapitulate human myeloid-carcinoma interactions in vitro. Tumoroid cultures suppress gene expression programs involved in inflammation and immune cell migration, providing a reductive platform for re-establishing carcinoma-immune cell interactions in vitro. Introduction of human monocyte-derived macrophages into tumoroid cultures instructs macrophages to acquire immunosuppressive and pro-tumorigenic gene expression programs similar to those observed in vivo. This includes hallmark induction of SPP1, encoding Osteopontin, an extracellular CD44 ligand with established oncogenic effects. Taken together, these findings offer a framework for understanding CRC-TME interactions and provide a reductionist tool for modeling specific aspects of these interactions.

Disruptions in cell fate decisions and transformed enteroendocrine cells drive intestinal tumorigenesis in Drosophila

Most epithelial tissues are maintained by stem cells that produce the different cell lineages required for proper tissue function. Constant communication between different cell types ensures precise regulation of stem cell behavior and cell fate decisions. These cell-cell interactions are often disrupted during tumorigenesis, but mechanisms by which they are co-opted to support tumor growth in different genetic contexts are poorly understood. Here, we introduce PromoterSwitch, a genetic platform we established to generate large, transformed clones derived from individual adult Drosophila intestinal stem/progenitor cells. We show that cancer-driving genetic alterations representing common colon tumor genome landscapes disrupt cell fate decisions within transformed tissue and result in the emergence of abnormal cell fates. We also show that transformed enteroendocrine cells, a differentiated, hormone-secreting cell lineage, support tumor growth by regulating intestinal stem cell proliferation through multiple genotype-dependent mechanisms, which represent potential vulnerabilities that could be exploited for therapy.

Transcript CD81-215 may be a long noncoding RNA of stromal origin with tumor-promoting role in colon cancer

The role of tetraspanin CD81 in malignant transformation is best studied in colorectal cancer, and it appears that other transcripts beside the fully coding mRNA may also be dysregulated in malignant cells. Recent data from a comprehensive pan-cancer transcriptome analysis demonstrated differential activity of two alternative CD81 gene promoters in malignant versus nonmalignant gut mucosa. The promoter active in gut mucosa gives rise to transcripts CD81-203 and CD81-213, while the promoter active in colon and rectal cancer gives rise to transcripts CD81-205 and CD81-215. Our study aimed to explore the biomarker potential of the transcripts from the alternative CD81 gene promoters in colon cancer, as well as to investigate their structure and potential function using in silico tools. The analysis of the transcripts' expression in several colon cell lines cultivated in 2D and 3D and a set of colon cancer and healthy gut mucosa samples by qPCR and RNA sequencing suggested their low expression and stromal origin. Expression patterns in tumor and nontumor tissue along with in silico data suppose that the transcript CD81-215 may be a noncoding RNA of stromal origin with possible involvement in signaling related to malignant transformation.

Complete mesocolic excision for right colon cancer: Is D3 lymphadenectomy necessary?

AIM

Although complete mesocolic excision (CME) for colon cancer is oncologically sound, to date, there has been no consensus on the extent of lymphadenectomy in radical right colectomy. This study essentially compared the perioperative and survival outcomes of CME with two templates of lymphadenectomy for right colon cancer.

METHOD

This was a propensity matched, retrospective analysis of a single centre, prospectively maintained database of all patients undergoing elective right colectomy for nonmetastatic, biopsy-proven adenocarcinoma from November 2013 to October 2018. CME + D3 was adopted selectively, documented prospectively, and compared with patients undergoing CME + central vascular ligation (CVL). The only technical difference between the groups was the excision of the surgical trunk of Gillot in the CME + D3 group. Postoperative, long-term outcomes and patterns of recurrence were compared between the groups.

RESULTS

Of the 244 eligible patients, 88 (36.1%) and 156 (63.9%) underwent CME + D3 and CME + CVL, respectively. Matched groups (72 [CME + D3] vs. 108 [CME + CVL]) showed no difference in histology, tumour grade, postoperative complications, mortality, and hospital stay. CME + D3 was preferentially performed laparoscopically (35.2% vs. 9%), was associated with lower blood loss (215 mL vs. 297 mL, p = 0.001), higher nodal yield (31 vs. 25 nodes, p = 0.003) and a higher incidence of chyle leak (4 vs. 0, p = 0.013). At a median follow-up of more than 57 months, there was no significant difference in local recurrence, disease-free or overall survival.

CONCLUSION

In this retrospective study, lymphadenectomy along the superior mesenteric vein, as a component of CME for right colon cancer, offered a higher nodal yield with no improvement in oncological outcome. Dissection of the SMV, over and above a D2 dissection, could therefore be restricted to specialized colorectal units until further studies establish the incremental oncological benefit of this extended lymphadenectomy or define a patient group in whom it is beneficial.

METTL3 promotes colorectal cancer progression through activating JAK1/STAT3 signaling pathway

The role of METTL3-mediated N6-methyladenosine (m6A) modification has been elucidated in several cancers, but the concrete mechanism underlying its function in colorectal cancer is still obscure. Here, we revealed that upregulated methyltransferase-like 3 (METTL3) in colorectal cancer exerted both methyltransferase activity-dependent and -independent functions in gene regulation. METTL3 deposited m6A on the 3' untranslated region of the JAK1 transcript to promote JAK1 translation relying on YTHDF1 recognition. Besides, METTL3 was redistributed to the STAT3 promoter and worked in concert with NF-κB to facilitate STAT3 transcription, which was achieved independently on METTL3 methyltransferase activity. The increased JAK1 and STAT3 corporately contributed to the activation of the p-STAT3 signaling pathway and further upregulated downstream effectors expressions, including VEGFA and CCND1, which finally resulted in enhanced cancer cell proliferation and metastasis in vitro and in vivo. Collectively, our study revealed the unappreciated dual role of METTL3 as an m6A writer and a transcription regulator, which worked together in the same signaling pathway to drive colorectal cancer malignancy.

Mn(II) Optimized Sono/Chemodynamic Effect of Porphyrin-Metal-Organic Framework Nanosheets for MRI-Guided Colon Cancer Therapy and Metastasis Suppression

Sonodynamic therapy (SDT) offers a remarkable non-invasive ultrasound (US) treatment by activating sonosensitizer and generating reactive oxygen species (ROS) to inhibit tumor growth. The development of multifunctional, biocompatible, and highly effective sonosensitizers remains a current priority for SDT. Herein, the first report that Mn(II) ions chelated Gd-TCPP (GMT) nanosheets (NSs) are synthesized via a simple reflux method and encapsulated with pluronic F-127 to form novel sonosensitizers (GMTF). The GMTF NSs produce a high yield of ROS under US irradiation due to the decreased highest occupied molecular orbital-lowest unoccupied molecular orbital gap energy (2.7-1.28 eV). Moreover, Mn(II) ions endow GMTF with a fascinating Fenton-like activity to produce hydroxyl radicals in support of chemodynamic therapy (CDT). It is also effectively used in magnetic resonance imaging (MRI) with high relaxation rate (r 1 : 4.401 mM-1  s-1 ) to track the accumulation of NSs in tumors. In vivo results indicate that the SDT and CDT in combination with programmed cell death protein 1 antibody (anti-PD-1) show effective metastasis prevention effects, and 70% of the mice in the GMTF + US + anti-PD-1 group survived for 60 days. In conclusion, this study develops a sonosensitizer with promising potential for utilizing both MRI-guided SDT and CDT strategies.

Nrf3 alleviates oxidative stress and promotes the survival of colon cancer cells by activating AKT/BCL-2 signal pathway

Oxidative stress is closely linked to tumor initiation and development, conferring a survival advantage to cancer cells. Therefore, understanding cancer cells' antioxidant molecular mechanisms is crucial to cancer therapy. In this study, we discovered that H2O2-induced oxidative stress increased Nrf3 expression in colon cancer cells. Overexpression of Nrf3 decreased H2O2-mediated cytotoxicity and apoptosis. Furthermore, Nrf3 reduced reactive oxygen species levels and malondialdehyde concentrations after H2O2 treatment. Mechanistically, H2O2-mediated cell apoptosis involves multiple signaling proteins, including Akt, bcl-2, JNK, and p38. An increase in Nrf3 expression in colon cancer cells treated with H2O2 partly reversed Akt/Bcl-2 inhibition, whereas it decreased activation of p38 and JNK. In addition, we found that increasing Nrf3 decreased stress-associated chemical-induced cell death, resulting in drug resistance. According to these results, Nrf3 is critical for drug resistance and oxidant adaptation.

ID1 expressing macrophages support cancer cell stemness and limit CD8+ T cell infiltration in colorectal cancer

Elimination of cancer stem cells (CSCs) and reinvigoration of antitumor immunity remain unmet challenges for cancer therapy. Tumor-associated macrophages (TAMs) constitute the prominant population of immune cells in tumor tissues, contributing to the formation of CSC niches and a suppressive immune microenvironment. Here, we report that high expression of inhibitor of differentiation 1 (ID1) in TAMs correlates with poor outcome in patients with colorectal cancer (CRC). ID1 expressing macrophages maintain cancer stemness and impede CD8+ T cell infiltration. Mechanistically, ID1 interacts with STAT1 to induce its cytoplasmic distribution and inhibits