Tumor microenvironment involvement in colorectal cancer progression via Wnt/β-catenin pathway:Providing understanding of the complex mechanisms of chemoresistance

Colorectal cancer(CRC)continues to be one of the main causes of death from cancer because patients progress unfavorably due to resistance to current therapies.Dysregulation of the Wnt/β-catenin pathway plays a fundamental role in the genesis and progression of several types of cancer,including CRC.In many subtypes of CRC,hyperactivation of theβ-catenin pathway is associated with mutations of the adenomatous polyposis coli gene.However,it can also be associated with other causes.In recent years,studies of the tumor microenvironment(TME)have demonstrated its importance in the development and progression of CRC.In this tumor nest,several cell types,structures,and biomolecules interact with neoplastic cells to pave the way for the spread of the disease.Cross-communications between tumor cells and the TME are then established primarily through paracrine factors,which trigger the activation of numerous signaling pathways.Crucial advances in the field of oncology have been made in the last decade.This Minireview aims to actualize what is known about the central role of the Wnt/β-catenin pathway in CRC chemoresistance and aggressiveness,focusing on crosscommunication between CRC cells and the TME.Through this analysis,our main objective was to increase the understanding of this complex disease considering a more global context.Since many treatments for advanced CRC fail due to mechanisms involving chemoresistance,the data here exposed and analyzed are of great interest for the development of novel and effective therapies.

Role of doublecortin-like kinase 1 and leucine-rich repeat-containing G-protein-coupled receptor 5 in patients with stage Ⅱ/Ⅲ colorectal cancer:Cancer progression and prognosis

BACKGROUND Cancer stem cells(CSCs)are a subpopulation of cancer cells with the potential of self-renewal and differentiation.CSCs play critical roles in tumorigenesis,recurrence,metastasis,radiation tolerance and chemoresistance.AIM To assess the expression patterns and clinical potential of doublecortin-like kinase 1(DCLK1)and leucine-rich repeat-containing G-protein-coupled receptor 5(Lgr5),as prognostic CSC markers of colorectal cancer(CRC).METHODS The expression of DCLK1 and Lgr5 in CRC tissue sections from 92 patients was determined by immunohistochemistry.Each case was evaluated using a combined scoring method based on signal intensity staining(scored 0-3)and the proportion of positively stained cancer cells(scored 0-3).The final staining score was calculated as the intensity score multiplied by the proportion score.Low expression of DCLK1 and Lgr5 was defined as a score of 0-3;high expression of DCLK1 and Lgr5 was defined as a score of≥4.Specimens were categorized as either high or low expression,and the correlation between the expression of DCLK1 or Lgr5 and clinicopathological factors was investigated.RESULTS DCLK1 and Lgr5 expression levels were significantly positively correlated.CRC patients with high DCLK1,Lgr5 and DCLK1/Lgr5 expressions had poorer progression-free survival and overall survival.Moreover,high expression of DCLK1 was an independent prognostic factor for recurrence and overall survival in patients with CRC by multivariate analysis(P=0.026 and P=0.049,respectively).CONCLUSION DCLK1 may be a potential CSC marker for the recurrence and survival of CRC patients.

The burgeoning importance of PIWI-interacting RNAs in cancer progression

PIWI-interacting RNAs(pi RNAs)are a class of small noncoding RNA molecules that specifically bind to piwi protein family members to exert regulatory functions in germ cells.Recent studies have found that pi RNAs,as tissue-specific molecules,both play oncogenic and tumor suppressive roles in cancer progression,including cancer cell proliferation,metastasis,chemoresistance and stemness.Additionally,the atypical manifestation of pi RNAs and PIWI proteins in various malignancies presents a promising strategy for the identification of novel biomarkers and therapeutic targets in the diagnosis and management of tumors.Nonetheless,the precise functions of pi RNAs in cancer progression and their underlying mechanisms have yet to be fully comprehended.This review aims to examine current research on the biogenesis and functions of pi RNA and its burgeoning importance in cancer progression,thereby offering novel perspectives on the potential utilization of pi RNAs and piwi proteins in the management and treatment of advanced cancer.

Extracellular matrix in cancer progression and therapy

The tumor ecosystem with heterogeneous cellularcompositions and the tumor microenvironment has increasingly become the focus of cancer research in recent years. Theextracellular matrix (ECM), the major component of the tumor microenvironment, and its interactions with the tumorcells and stromal cells have also enjoyed tremendouslyincreased attention. Like the other components of the tumormicroenvironment, the ECM in solid tumors differs significantly from that in normal organs and tissues. We reviewrecent studies of the complex roles the tumor ECM plays incancer progression, from tumor initiation, growth to angiogenesis and invasion. We highlight that the biomolecular,biophysical, and mechanochemical interactions between theECM and cells not only regulate the steps of cancer progression, but also affect the efficacy of systemic cancer treatment.We further discuss the strategies to target and modify thetumor ECM to improve cancer therapy.

AKR1B1 promotes basal-like breast cancer progression by activating the EMT program

Subject Code:H16With the support by the National Natural Science Foundation of China,a study by the research groups led by Prof.Dong Chenfang(董辰方)from Zhejiang University School of Medicine demonstrates that AKR1B1promotes basal-like breast cancer progression by apositive feedback loop that activates the

How the interplay among the tumor microenvironment and the gut microbiota influences the stemness of colorectal cancer cells

Colorectal cancer(CRC)remains the third most prevalent cancer disease and involves a multi-step process in which intestinal cells acquire malignant characteristics.It is well established that the appearance of distal metastasis in CRC patients is the cause of a poor prognosis and treatment failure.Nevertheless,in the last decades,CRC aggressiveness and progression have been attributed to a specific cell population called CRC stem cells(CCSC)with features like tumor initiation capacity,self-renewal capacity,and acquired multidrug resistance.Emerging data highlight the concept of this cell subtype as a plastic entity that has a dynamic status and can be originated from different types of cells through genetic and epigenetic changes.These alterations are modulated by complex and dynamic crosstalk with environmental factors by paracrine signaling.It is known that in the tumor niche,different cell types,structures,and biomolecules coexist and interact with cancer cells favoring cancer growth and development.Together,these components constitute the tumor microenvironment(TME).Most recently,researchers have also deepened the influence of the complex variety of microorganisms that inhabit the intestinal mucosa,collectively known as gut microbiota,on CRC.Both TME and microorganisms participate in inflammatory processes that can drive the initiation and evolution of CRC.Since in the last decade,crucial advances have been made concerning to the synergistic interaction among the TME and gut microorganisms that condition the identity of CCSC,the data exposed in this review could provide valuable insights into the biology of CRC and the development of new targeted therapies.

Roles of cell fusion, hybridization and polyploid cell formation in cancer metastasis

Cell-cell fusion is a normal biological process playing essential roles in organ formation and tissue differentiation,repair and regeneration.Through cell fusion somatic cells undergo rapid nuclear reprogramming and epigenetic modifications to form hybrid cells with new genetic and phenotypic properties at a rate exceeding that achievable by random mutations.Factors that stimulate cell fusion are inflammation and hypoxia.Fusion of cancer cells with non-neoplastic cells facilitates several malignancy-related cell phenotypes,e.g.,reprogramming of somatic cell into induced pluripotent stem cells and epithelial to mesenchymal transition.There is now considerable in vitro,in vivo and clinical evidence that fusion of cancer cells with motile leucocytes such as macrophages plays a major role in cancer metastasis.Of the many changes in cancer cells after hybridizing with leucocytes,it is notable that hybrids acquire resistance to chemo-and radiation therapy.One phenomenon that has been largely overlooked yet plays a role in these processes is polyploidization.Regardless of the mechanism of polyploid cell formation,it happens in response to genotoxic stresses and enhances a cancer cell’s ability to survive.Here we summarize the recent progress in research of cell fusion and with a focus on an important role for polyploid cells in cancer metastasis.In addition,we discuss the clinical evidence and the importance of cell fusion and polyploidization in solid tumors.

The expressional level of tankyrase-1 gene and its regulation in colorectal cancer in a Saudi population

Tankyrase1(TNKS1)plays an essential role in cancer progression by regulating telomere length.The study aimed to determine expression of TNKS1 and its regulation in colorectal cancer(CRC)in 20 samples from Saudi patients.mRNA expression of TNKS1 in CRC and paired normal tissues was measured by qRT-PCR.Epigenetic modification of TNKS1 promoter was determined by methylation-specific PCR while somatic mutation was analyzed by Sanger sequencing in exon 10 of the gene.All cancerous and normal tissues expressed TNKS1,but level of expression in CRC tissues was significantly associated with tumor stage though no other parameters;age,gender,and tumor location,showed any correlation.Expression of TNKS1 was markedly higher in earlier(I,II)than in later(Ⅲ,Ⅳ)stages of CRC development.Both cancerous and healthy tissues had unmethylated promoters.Sanger sequencing of exon 10 masked any somatic mutation in the samples.Our findings suggest that up-regulation of TNKS1 was inversely correlated with cancer progression in CRC,indicating that TNKS1 participates in the initiation of CRC by stabilizing telomere length in the first phase of cancer progression.Mechanisms other than TNKS1 might play a role in malignant tumor progression and telomere maintenance in the late stages of CRC.

Angiotensin-converting enzyme 2 connects COVID-19 with cancer and cancer immunotherapy

The coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in more than two million deaths.Underlying diseases,including cancer,are high-risk factors for severe COVID-19 outcomes.Angiotensin-converting enzyme 2(ACE2),as a SARS-CoV-2 host cell receptor,plays a crucial role in SARS-CoV-2 invading human cells.ACE2 also has significant associations with cancer.Recent studies showed that ACE2 was inversely correlated with the activities of multiple oncogenic pathways and tumor progression phenotypes,and was positively correlated with antitumor immune response and survival prognosis in diverse cancers,suggesting a potential protective role of ACE2 in cancer progression.Positive expression of ACE2 is also correlated with programmed death-ligand 1(PD-L1)in cancer.The positive associations of ACE2 expression with antitumor immune signatures and PD-L1 expression indicate that ACE2 expression is a positive predictor for the response to immune checkpoint inhibitors(ICIs).This was evidenced in multiple cancer cohorts treated with ICIs.Thus,ACE2 may build potential connections between COVID-19 and cancer and cancer immunotherapy.The potential connections suggest that ACE2 inhibitors may not be a good option for treating COVID-19 patients with cancer,particularly in cancer patients who are receiving immunotherapy.Furthermore,the relationships between ACE2,COVID-19,and cancer are worth confirming by more experimental and clinical data,considering that many cancer patients are at high risk for COVID-19.

KCNJ15 deficiency promotes drug resistance via affecting the function of lysosomes

The altered lysosomal function can induce drug redistribution which leads to drug resistance and poor prognosis for cancer patients.V-ATPase,an ATP-driven proton pump positioned at lysosomal surfaces,is responsible for maintaining the stability of lysosome.Herein,we reported that the potassium voltage-gated channel subfamily J member 15(KCNJ15)protein,which may bind to V-ATPase,can regulate the function of lysosome.The deficiency of KCNJ15 protein in breast cancer cells led to drug aggregation as well as reduction of drug efficacy.The application of the V-ATPase inhibitor could inhibit the binding between KCNJ15 and V-ATPase,contributing to the amelioration of drug resistance.Clinical data analysis revealed that KCNJ15 deficiency was associated with higher histological grading,advanced stages,more metastases of lymph nodes,and shorter disease free survival of patients with breast cancer.KCNJ15 expression level is positively correlated with a high response rate after receiving neoadjuvant chemotherapy.Moreover,we revealed that the small molecule drug CMA/BAF can reverse drug resistance by disrupting the interaction between KCNJ15 and lysosomes.In conclusion,KCNJ15 could be identified as an underlying indicator for drug resistance and survival of breast cancer,which might guide the choice of therapeutic strategies.

Multifaceted roles and functions of SOX30 in human cancer

SRY-box transcription factor 30(SOX30)participates in tumor cell apoptosis in lung cancer.The occurrence of somatic SOX30 mutations,the expression signature of SOX30 in normal and cancer tissues,the correlation of SOX30 with immune cells and immune-related genes,and the clinical significance of SOX30 in various cancers have stimulated interest in SOX30 as a potential cancer biomarker.SOX30 influences drug sensitivity and tumor immunity in specific cancer types.In this review,we have comprehensively summarized the latest research on the role of SOX30 in cancer by combining bioinformatics evidence and a literature review.We summarize recent research on SOX30 in cancer regarding somatic mutations,trials,transcriptome analysis,clinical information,and SOX30-mediated regulation of malignant phenotypes.Additionally,we report on the diagnostic value of SOX30 mRNA expression levels across different cancer types.This review on the role of SOX30 in cancer progression may provide insights into possible research directions for SOX30 in cancer and a theoretical basis for guiding future studies.

Function of cancer cell-derived extracellular matrix in tumor progression

Extracellular matrix(ECM)is an essential component of the tumor microenvironment.Cancer development and progression are associated with increased ECM deposition and crosslink.The chemical and physical signals elicited from ECM are necessary for cancer cell proliferation and invasion.It is well recognized that stromal cells are a major source of ECM proteins.However,recent studies showed that cancer cells are also an active and important component in ECM remodeling.Cancer cells deposit a significant amount of collagen,fibronectin,and tenascin C(TNC).Recent studies demonstrate that these cancer cell-derived ECM proteins enhance cancer cell survival and promote cancer cell colonization at distant sites.ECM-related enzymes and chaperone proteins,such as prolyl-4-hydroxylase,lysyl-hydroxylase,lysyl oxidase,and heat shock protein 47,are also highly expressed in cancer cells.Inhibition of these enzymes significantly reduces cancer growth,invasion,and metastasis.These factors suggest that the cancer cell-derived ECM is crucial for cancer progression and metastasis.Therefore,targeting these ECM proteins and ECM-related enzymes is a potential strategy for cancer treatment.

RNA editingof SLC22A3 causes early tumor progression in familial esophageal cancer patients

Subject Code:H16With the support by the National Natural Science Foundation of China,a collaborative study by the Research groups led by Prof.Fu Li(付利)from the Cancer Research Center,Shenzhen University School of Medicine and Prof.Guan Xinyuan(关新元)from the University of Hong Kong reported that an

The size of cell-free mitochondrial DNA in blood is inversely correlated with tumor burden in cancer patients

Circulating cell-free DNAs(cfDNAs)are fragmented DNA molecules released into the blood by cells.Previous studies have suggested that mitochondria-originated cfDNA fragments(mt-cfDNAs)in cancer patients are more fragmented than those from healthy controls.However,it is still unknown where these short mtcfDNAs originate,and whether the length of mt-cfDNAs can be correlated with tumor burden and cancer progression.In this study,we first performed whole-genome sequencing analysis(WGS)of cfDNAs from a human tumor cell line-xenotransplantation mouse model and found that mt-cfDNAs released from transplanted tumor cells were shorter than the mouse counterpart.We next analyzed blood cfDNA samples from hepatocellular carcinoma and prostate cancer patients and found that mt-cfDNA lengths were inversely related to tumor size as well as the concentration of circulating tumor DNA.Our study suggested that monitoring the size of mt-cfDNAs in cancer patients would be a useful way to estimate tumor burden and cancer progression.

Elucidation of drivers of high-level production of lactates throughout a cancer development

Lactates play key roles in facilitating or protecting the development of a cancer in most cancer types.While its beneficial effects to cancer development have been extensively studied,very little is known about what derives the high-level production of lactates in a cancer throughout its entire development.Here we present a novel computational analysis of transcriptomic data of nine primary cancer types,plus a few precancerous and metastatic cancer,to address this issue.Our approach is to identify stress types,which are known to play key roles in cancer development and show strong co-expressions with lactate dehydrogenase-A(LDHA),at different stages of cancer development.A number of interesting observations are made through our analyses,including(i)all nine primary cancer types show similar association patterns between stresses and LDHA,namely the strengths of the associations increase from early-to intermediate-stage cancer tissues but then make a substantial down turn at the most advanced stage;(ii)while the detailed stress types associated with LDHA may vary across different cancer types,stresses induced by apoptosis and adaptive immune responses are present universally,suggesting that these two stresses are possibly two key drivers to keep the high-level production of lactates;and(iii)there is a clear distinction between stress types associated with LDHA in precancerous tissues vs.cancer and metastasis tissues.We anticipate that the analyses can provide highly useful information for designing personalized treatments for different cancers at different stages,as stopping lactate production could have devastating effects on a cancer development.

Circulating tumor cells in gastric cancer

Circulating tumor cells(CTCs)have received a lot of attention as a novel biomarker for cancer research in past decades.CTCs infiltrate the bloodstream derived from the primary tumor,and are significantly involved in cancer metastasis and recurrence.Although clinical applications have been challenging owing to the difficulties of CTC identification,recent development of technology for specific enrichment and detection of CTCs contributes to diagnosis and treatment.Furthermore,CTC analyses will shed new light on the biological mechanisms of cancer progression and metastasis.A number of clinical studies have already been carried out on the basis of CTC technology.Nevertheless,the clinical utility of CTCs is still unknown in gastric cancer.In this review,we elaborate on the latest advances of CTC research in gastric cancer.

Polo-like kinase 1,on the rise from cell cycle regulation to prostate cancer development

Polo-like kinase 1(Plk1),a well-characterized member of serine/threonine kinases Plk family,has been shown to play pivotal roles in mitosis and cytokinesis in eu-karyotic cells.Recent studies suggest that Plk1 not only controls the process of mitosis and cytokinesis,but also,going beyond those previously described functions,plays critical roles in DNA replication and Pten null prostate cancer initiation.In this review,we briefly summarize the functions of Plk1 in mitosis and cytokinesis,and then mainly focus on newly discov-ered functions of Plk1 in DNA replication and in Pten-null prostate cancer initiation.Furthermore,we briefly introduce the architectures of human and mouse pros-tate glands and the possible roles of Plk1 in human prostate cancer development.And finally,the newly chemotherapeutic development of small-molecule Plk1 inhibitors to target Plk1 in cancer treatment and their translational studies are also briefly reviewed.

Targeting an oncogenic kinase/phosphatase signaling network for cancer therapy

Protein kinases and phosphatases signal by phosphorylation and dephosphorylation to precisely control the activities of their individual and common substrates for a coordinated cellular outcome. In many situations, a kinase/phosphatase complex signals dynamically in time and space through their reciprocal regulations and their cooperative actions on a substrate. This complex may be essential for malignant transformation and progression and can therefore be considered as a target for therapeutic intervention. p38γ is a unique MAPK family member that contains a PDZ motif at its C-terminus and interacts with a PDZ domain-containing protein tyrosine phosphatase PTPH1. This PDZcoupled binding is required for both PTPH1 dephosphorylation and inactivation of p38γ and for p38γ phosphorylation and activation of PTPH1. Moreover, the p38γ/PTPH1 complex can further regulate their substrates phosphorylation and dephosphorylation, which impacts Ras transformation, malignant growth and progression, and therapeutic response. This review will use the p38γ/PTPH1 signaling network as an example to discuss the potential of targeting the kinase/phosphatase signaling complex for development of novel targeted cancer therapy.

The regulatory and modulatory roles of TRP family channels in malignant tumors and relevant therapeutic strategies

Transient receptor potential(TRP)channels are one primary type of calcium(Ca^(2+))permeable channels,and those relevant transmembrane and intracellular TRP channels were previously thought to be mainly associated with the regulation of cardiovascular and neuronal systems.Nowadays,however,accumulating evidence shows that those TRP channels are also responsible for tumorigenesis and progression,inducing tumor invasion and metastasis.However,the overall underlying mechanisms and possible signaling transduction pathways that TRP channels in malignant tumors might still remain elusive.Therefore,in this review,we focus on the linkage between TRP channels and the significant characteristics of tumors such as multi-drug resistance(MDR),metastasis,apoptosis,proliferation,immune surveillance evasion,and the alterations of relevant tumor micro-environment.Moreover,we also have discussed the expression of relevant TRP channels in various forms of cancer and the relevant inhibitors’efficacy.The chemo-sensitivity of the anti-cancer drugs of various acting mechanisms and the potential clinical applications are also presented.Furthermore,it would be enlightening to provide possible novel therapeutic approaches to counteract malignant tumors regarding the intervention of calcium channels of this type.