Peritoneal metastasis is a common form of distant metastasis in patients with colorectal cancer, and it is typically associated with a poor prognosis. The development of peritoneal metastasis involves complex molecular mechanisms and multifactorial regulation of the tumor microenvironment. Due to the presence of the blood-peritoneal barrier, only a small amount of systemic medication reaches the peritoneal cavity, resulting in limited efficacy against peritoneal metastasis. Intraperitoneal administration shows significant therapeutic advantages as it can directly target the tumor microenvironment, maintain high local drug concentrations, and reduce systemic toxicity. Intraperitoneal chemotherapy, especially hyperthermic intraperitoneal chemotherapy, has become a cornerstone therapeutic strategy in the clinical treatment of peritoneal metastasis. When selecting chemotherapy drugs and drug combinations, pharmacokinetic properties, efficacy, and safety must be comprehensively considered to optimize the treatment outcomes. In addition, the unique microenvironment of the peritoneal cavity provides new treatment approaches for biological treatment strategies, including antitoxins, vaccines, immune checkpoint inhibitors, etc. Techniques such as pressurized intraperitoneal aerosol chemotherapy and novel drug delivery systems demonstrate potential for enhanced efficacy, offering promising alternatives to improve patient outcomes. This article will review peritoneal barrier characteristics, intraperitoneal drug transport, intraperitoneal chemotherapy, and intraperitoneal biological therapies, thereby establishing a theoretical framework for precision therapy in colorectal cancer peritoneal metastasis.

Peritoneal metastasis is a common form of distant metastasis in patients with colorectal cancer, and it is typically associated with a poor prognosis. The development of peritoneal metastasis involves complex molecular mechanisms and multifactorial regulation of the tumor microenvironment. Due to the presence of the blood-peritoneal barrier, only a small amount of systemic medication reaches the peritoneal cavity, resulting in limited efficacy against peritoneal metastasis. Intraperitoneal administration shows significant therapeutic advantages as it can directly target the tumor microenvironment, maintain high local drug concentrations, and reduce systemic toxicity. Intraperitoneal chemotherapy, especially hyperthermic intraperitoneal chemotherapy, has become a cornerstone therapeutic strategy in the clinical treatment of peritoneal metastasis. When selecting chemotherapy drugs and drug combinations, pharmacokinetic properties, efficacy, and safety must be comprehensively considered to optimize the treatment outcomes. In addition, the unique microenvironment of the peritoneal cavity provides new treatment approaches for biological treatment strategies, including antitoxins, vaccines, immune checkpoint inhibitors, etc. Techniques such as pressurized intraperitoneal aerosol chemotherapy and novel drug delivery systems demonstrate potential for enhanced efficacy, offering promising alternatives to improve patient outcomes. This article will review peritoneal barrier characteristics, intraperitoneal drug transport, intraperitoneal chemotherapy, and intraperitoneal biological therapies, thereby establishing a theoretical framework for precision therapy in colorectal cancer peritoneal metastasis.

Objective To investigate the effect of Porphyromonas gingivalis(Pg)infection on immune escape of oesophageal cancer cells and the role of YTHDF2 and Fas in this regulatory mechanism.Methods We examined YTHDF2 and Fas protein expressions in esophageal squamous cell carcinoma(ESCC)tissues with and without Pg infection using immunohistochemistry and in Pg-infected KYSE150 cells using Western blotting.The interaction between YTHDF2 and Fas was investigated by co-immunoprecipitation(Co-IP).Pg-infected KYSE150 cells with lentivirus-mediated YTHDF2 knockdown were examined for changes in expression levels of YTHDF2,cathepsin B(CTSB),Fas and FasL proteins,and the effect of E64(a cathepsin inhibitor)on these proteins were observed.After Pg infection and E64 treatment,KYSE150 cells were co-cultured with human peripheral blood mononuclear cells(PBMCs),and the expressions of T cell-related effector molecules were detected by flow cytometry.Results ESCC tissues and cells with Pg infection showed significantly increased YTHDF2 expression and lowered Fas expression.The results of Co-IP demonstrated a direct interaction between YTHDF2 and Fas.In Pg-infected KYSE150 cells with YTHDF2 knockdown,the expression of CTSB was significantly reduced while Fas and FasL expressions were significantly increased.E64 treatment of KYSE150 cells significantly decreased the expression of CTSB without affecting YTHDF2 expression and obviously increased Fas and FasL expressions.Flow cytometry showed that in Pg-infected KYSE150 cells co-cultured with PBMCs,the expressions of Granzyme B and Ki67 were significantly decreased while PD-1 expression was significantly enhanced.Conclusion Pg infection YTHDF2-dependently regulates the expression of Fas to facilitate immune escape of esophageal cancer and thus promoting cancer progression,suggesting the key role of YTHDF2 in regulating immune escape of esophageal cancer.

Objective To explore the correlation of baseline CCL19+dendritic cell(CCL19+DC)infiltration in lung adenocarcinoma microenvironment with immunotherapy efficacy and CD8+T cell infiltration.Methods We retrospectively analyzed the data of patients with lung adenocarcinoma hospitalized at First Affiliated Hospital of Henan University of Science and Technology from January,2020 to December,2023,and collected tissue samples from 96 patients undergoing immunotherapy for assessing CCL19+DC and CD8+T cell infiltration using immunofluorescence assay.We evaluated the predictive value of baseline CCL19+DCs for patient responses to immunotherapy using receiver-operating characteristics(ROC)curves and analyzed the correlations of baseline CCL19+DC expression with immunotherapy efficacy and CD8+T cell and cytotoxic T lymphocyte(CTL)infiltrations.In co-culture systems of lung adenocarcinoma PC9 cells,CD8+T cells and DCs(overexpressing CCL19 with or without anti PD-1 antibody treatment),the expressions of granzyme B,perforin,IFN-γ,and Ki-67 in T cells were analyzed using flow cytometry.Results The patients with partial or complete remission following immunotherapy had a significantly higher baseline CCL19+DC infiltration level in lung adenocarcinoma tissues than those with poor responses.CCL19+DC infiltration had an area under ROC curve of 0.785,a sensitivity of 75.6%,and a specificity of 62.8%for predicting immunotherapy efficacy.The expression of CD8+T cell surface molecules Granzyme B(P<0.01),Perforin(P<0.01),IFN-γ(P<0.01)and Ki-67(P<0.001)in patients with high expression of CCL19+DC were higher than those in patients with low expression of CCL19+DC.The baseline CCL19+DC infiltration level was positively correlated with immunotherapy efficacy(P=0.003),CTL infiltration of(r=0.6657,P<0.001)and CD8+T cell infiltration(P=0.007).In the co-cultured cells,CCL19 overexpression combined with anti-PD1 treatment of the DCs more strongly enhanced cytotoxicity and proliferation of CD8+T lymphocytes than either of the single treatments(P<0.01 or 0.001).Conclusion The baseline CCL19+DC infiltration level in lung adenocarcinoma microenvironment is positively correlated with immunotherapy efficacy and CTL infiltration and can thus predict the response to immunotherapy.

Objective To investigate the mechanism through which RgpB,a virulence factor of Porphyromonas gingivalis(Pg),induces chemoresistance in esophageal squamous carcinoma.Methods The autophagy-regulating factors that interact with RgpB were screened by immunoprecipitation-mass spectrometry.The interaction between RgpB and the autophagy regulator TBC1D5 was investigated using co-immunoprecipitation.The impact of Pg infection on the expression of esophageal cancer cell membrane receptor molecule Cx43 was assessed using Western blotting.Immunofluorescence assay was used to analyze the relationship among Lamp1,Cx43 and TBC1D5.The effect of Pg infection on autophagosome-lysosome fusion was evaluated using autophagy double fluorescence technique.The effects of Pg infection and a Cx43 inhibitor on proliferation of esophageal cancer cells after chemotherapy were examined with plate cloning assay and CCK-8 method.Results Immunoprecipitation-mass spectrometry identified TBC1D5 as an autophagy regulator interacting with RgpB,and co-immunoprecipitation suggested that RgpB could directly bind to TBC1D5.In Pg-infected esophageal cancer cells,the expression of Cx43 on the cell membrane was significantly higher than that in non-infected cells.Immunofluorescence assay showed that the expression of Cx43 on the membrane of esophageal cancer cells increased significantly after Pg infection,which blocked autophagosome-lysosome fusion as shown by stubRFP-sensGFP-LC3 lentivirus study.Plate cloning assay and CCK-8 assay showed that the Cx43 inhibitor significantly attenuated the effect of Pg infection for promoting proliferation of esophageal cancer cells after chemotherapy.Conclusion Pg infection in esophageal cancer blocked autophagosome-lysosome fusion in the tumor cells,thereby preventing Cx43 from lysosomal degradation and leading to chemoresistance of esophageal cancer.

Objective: To establish aNBR1-knockout lung cancer mouse model through CRISPR-Cas9 technology by using adeno-associated virus(AAV) as a vector to specifically inhibitNBR1expression and to investigate the impact ofNBR1knockout on tumor growth and immune cell infiltration and regulation. Methods: sgRNAs targeting mouseNBR1(Gene ID: 17966) was designed using the online tool CRISPOR(http://crispor.tefor.net/crispor.py). AAV6 was utilized as the vector for sgRNA delivery, and the efficiency of gene knockout was confirmed using PCR and DNA sequencing methods. To determine the best AAV infection approach in mice, 6 C57BL/6J mice were randomly divided into intranasal and endotracheal groups. After 28 days, lung tissue sections were assessed for enhanced green fluorescent protein expression to identify the more efficient infection method for subsequent experiments. Lung tumor growth, as well as immune cell infiltration and activation status in tumor tissues, were detected using methods including HE staining, immunohistochemistry, immunofluorescence, and flow cytometry. Results: DNA sequencing and immunofluorescence results indicated successful construction of the AAV6-U6-sgNBR1-CAG-Cre-GFP vector with stable knockout efficiency. Fluorescence microscopy showed higher efficiency of lung infection in mice through intratracheal administration(P<0.05). HE staining revealed reduced tumor area in mouse lungs after targetedNBR1knockout compared to the control group(P<0.01). Immunofluorescence and flow cytometry results demonstrated enhanced functional activity of CD8+T lymphocytes in lung cancer tissues of mice with targetedNBR1knockout, characterized by increased effector T lymphocytes and decreased exhausted T lymphocytes(P<0.01). Conclusion Using CRISPR/Cas9 technology, we construct a lung cancer mouse model with targetedNBR1knockout. We verify that targeted inhibition of NBR1 expression significantly enhances the functional activity of CD8+T lymphocytes in lung tissues, resulting in suppressed tumor growth, reduced tumor burden, and extended survival in lung cancer mice. This study lays an experimental foundation for investigations into the mechanisms and functions ofNBR1and other genes in lung adenocarcinoma cells.

Objective To investigate the effect of Porphyromonas gingivalis(Pg)infection on immune escape of oesophageal cancer cells and the role of YTHDF2 and Fas in this regulatory mechanism.Methods We examined YTHDF2 and Fas protein expressions in esophageal squamous cell carcinoma(ESCC)tissues with and without Pg infection using immunohistochemistry and in Pg-infected KYSE150 cells using Western blotting.The interaction between YTHDF2 and Fas was investigated by co-immunoprecipitation(Co-IP).Pg-infected KYSE150 cells with lentivirus-mediated YTHDF2 knockdown were examined for changes in expression levels of YTHDF2,cathepsin B(CTSB),Fas and FasL proteins,and the effect of E64(a cathepsin inhibitor)on these proteins were observed.After Pg infection and E64 treatment,KYSE150 cells were co-cultured with human peripheral blood mononuclear cells(PBMCs),and the expressions of T cell-related effector molecules were detected by flow cytometry.Results ESCC tissues and cells with Pg infection showed significantly increased YTHDF2 expression and lowered Fas expression.The results of Co-IP demonstrated a direct interaction between YTHDF2 and Fas.In Pg-infected KYSE150 cells with YTHDF2 knockdown,the expression of CTSB was significantly reduced while Fas and FasL expressions were significantly increased.E64 treatment of KYSE150 cells significantly decreased the expression of CTSB without affecting YTHDF2 expression and obviously increased Fas and FasL expressions.Flow cytometry showed that in Pg-infected KYSE150 cells co-cultured with PBMCs,the expressions of Granzyme B and Ki67 were significantly decreased while PD-1 expression was significantly enhanced.Conclusion Pg infection YTHDF2-dependently regulates the expression of Fas to facilitate immune escape of esophageal cancer and thus promoting cancer progression,suggesting the key role of YTHDF2 in regulating immune escape of esophageal cancer.

Objective To explore the correlation of baseline CCL19+dendritic cell(CCL19+DC)infiltration in lung adenocarcinoma microenvironment with immunotherapy efficacy and CD8+T cell infiltration.Methods We retrospectively analyzed the data of patients with lung adenocarcinoma hospitalized at First Affiliated Hospital of Henan University of Science and Technology from January,2020 to December,2023,and collected tissue samples from 96 patients undergoing immunotherapy for assessing CCL19+DC and CD8+T cell infiltration using immunofluorescence assay.We evaluated the predictive value of baseline CCL19+DCs for patient responses to immunotherapy using receiver-operating characteristics(ROC)curves and analyzed the correlations of baseline CCL19+DC expression with immunotherapy efficacy and CD8+T cell and cytotoxic T lymphocyte(CTL)infiltrations.In co-culture systems of lung adenocarcinoma PC9 cells,CD8+T cells and DCs(overexpressing CCL19 with or without anti PD-1 antibody treatment),the expressions of granzyme B,perforin,IFN-γ,and Ki-67 in T cells were analyzed using flow cytometry.Results The patients with partial or complete remission following immunotherapy had a significantly higher baseline CCL19+DC infiltration level in lung adenocarcinoma tissues than those with poor responses.CCL19+DC infiltration had an area under ROC curve of 0.785,a sensitivity of 75.6%,and a specificity of 62.8%for predicting immunotherapy efficacy.The expression of CD8+T cell surface molecules Granzyme B(P<0.01),Perforin(P<0.01),IFN-γ(P<0.01)and Ki-67(P<0.001)in patients with high expression of CCL19+DC were higher than those in patients with low expression of CCL19+DC.The baseline CCL19+DC infiltration level was positively correlated with immunotherapy efficacy(P=0.003),CTL infiltration of(r=0.6657,P<0.001)and CD8+T cell infiltration(P=0.007).In the co-cultured cells,CCL19 overexpression combined with anti-PD1 treatment of the DCs more strongly enhanced cytotoxicity and proliferation of CD8+T lymphocytes than either of the single treatments(P<0.01 or 0.001).Conclusion The baseline CCL19+DC infiltration level in lung adenocarcinoma microenvironment is positively correlated with immunotherapy efficacy and CTL infiltration and can thus predict the response to immunotherapy.

Objective To investigate the mechanism through which RgpB,a virulence factor of Porphyromonas gingivalis(Pg),induces chemoresistance in esophageal squamous carcinoma.Methods The autophagy-regulating factors that interact with RgpB were screened by immunoprecipitation-mass spectrometry.The interaction between RgpB and the autophagy regulator TBC1D5 was investigated using co-immunoprecipitation.The impact of Pg infection on the expression of esophageal cancer cell membrane receptor molecule Cx43 was assessed using Western blotting.Immunofluorescence assay was used to analyze the relationship among Lamp1,Cx43 and TBC1D5.The effect of Pg infection on autophagosome-lysosome fusion was evaluated using autophagy double fluorescence technique.The effects of Pg infection and a Cx43 inhibitor on proliferation of esophageal cancer cells after chemotherapy were examined with plate cloning assay and CCK-8 method.Results Immunoprecipitation-mass spectrometry identified TBC1D5 as an autophagy regulator interacting with RgpB,and co-immunoprecipitation suggested that RgpB could directly bind to TBC1D5.In Pg-infected esophageal cancer cells,the expression of Cx43 on the cell membrane was significantly higher than that in non-infected cells.Immunofluorescence assay showed that the expression of Cx43 on the membrane of esophageal cancer cells increased significantly after Pg infection,which blocked autophagosome-lysosome fusion as shown by stubRFP-sensGFP-LC3 lentivirus study.Plate cloning assay and CCK-8 assay showed that the Cx43 inhibitor significantly attenuated the effect of Pg infection for promoting proliferation of esophageal cancer cells after chemotherapy.Conclusion Pg infection in esophageal cancer blocked autophagosome-lysosome fusion in the tumor cells,thereby preventing Cx43 from lysosomal degradation and leading to chemoresistance of esophageal cancer.

Objective: To investigate the effect of Porphyromonas gingivallis ( Pg) infection of esophageal cancer cells on the polarization of tumor associated macrophages (TAMs) and functional changes. Methods: The secretion of tumor⁃related cytokines in the supernatant of Pg infected and uninfected esophageal squamous cell carcinoma (ESCC) cells was detected by ELISA. A co⁃culture model of ESCC cells and macrophages in vitro was established ,and the changes of TAMs surface markers were detected by qPCR , cellular immunofluorescence and flow cytometry. Cytokines secreted by TAMs after co⁃culture were detected by ELISA. ESCC cells were cultured using conditioned medium of co⁃cultured TAMs , and the effects of TAMs on the proliferation , migration and invasion of esophageal cancer cells were evaluated by CCK⁃8 , Wound⁃healing assay and Transwell assay. Results: The expression quantity of IL⁃6 and IL⁃10 of Pg⁃infected ESCC cells increased (P < 0. 01) . The contents of CD163 and CD206 on the surface of TAMs co⁃cultured with Pg⁃infected ESCC cells increased (P < 0. 001) . The cytokines IL⁃6 and IL⁃10 secreted by TAMs co⁃cultured with Pg⁃infected ESCC cells relatively increased (P < 0. 01) . TAMs co⁃cultured with Pginfected ESCC cells were able to enhance ESCC cells proliferation , migration and invasion (all P < 0. 05) . Conclusion Pg infection of ESCC cells can induce the secretion of cytokines , remodel TAMs to polarize toward the M2type immunosuppressive phenotype , thereby promoting the malignant biological behavior of ESCC cells. This study provides data support for the etiology of esophageal cancer and potential target molecules for clinical immunotherapy targeting TAMs.