FADS2 confers SCD1 inhibition resistance to cancer cells by modulating the ER stress response.

Stearoyl-CoA desaturase 1 (SCD1) is an attractive target for cancer therapy. However, the clinical efficacy of SCD1 inhibitor monotherapy is limited. There is thus a need to elucidate the mechanisms of resistance to SCD1 inhibition and develop new therapeutic strategies for combination therapy. In this study, we investigated the molecular mechanisms by which cancer cells acquire resistance to endoplasmic reticulum (ER) stress-dependent cancer cell death induced by SCD1 inhibition. SCD1 inhibitor-sensitive and -resistant cancer cells were treated with SCD1 inhibitors in vitro, and SCD1 inhibitor-sensitive cancer cells accumulated palmitic acid and underwent ER stress response-induced cell death. Conversely, SCD1-resistant cancer cells did not undergo ER stress response-induced cell death because fatty acid desaturase 2 (FADS2) eliminated the accumulation of palmitic acid. Furthermore, genetic depletion using siRNA showed that FADS2 is a key determinant of sensitivity/resistance of cancer cells to SCD1 inhibitor. A549 cells, an SCD1 inhibitor-resistant cancer cell line, underwent ER stress-dependent cancer cell death upon dual inhibition of SCD1 and FADS2. Thus, combination therapy with SCD1 inhibition and FADS2 inhibition is potentially a new cancer therapeutic strategy targeting fatty acid metabolism.

Gastric-type adenocarcinoma of the uterine cervix: clinical features and future directions.

The concept of gastric-type mucinous carcinoma of the uterine cervix (GAS) has been accepted worldwide because of its aggressive clinical behaviour and the absence of high-risk human papilloma virus infection. The World Health Organization (WHO) 2020 classification divides cervical tumours into two categories: human papilloma virus-associated and human papilloma virus-independent. Hence, GAS is now classified as an human papilloma virus-independent gastric type. Because clinical studies have reported that GAS is refractory to conventional treatments such as chemotherapy and radiotherapy, especially at an advanced stage, and has aggressive features with widespread dissemination to unusual sites, such as the omentum, peritoneum and distant organs, it is urgent to establish new treatment strategies by comparing the molecular profiles of human papilloma virus-associated adenocarcinomas. A series of genetic mutations characteristic to GAS encourage the development of future treatment strategies such as targeted therapy and immunotherapy.

Solid tumours showing oligoprogression to immune checkpoint inhibitors have the potential for abscopal effects.

PURPOSE: Given the uncertainty surrounding the abscopal effect (AE), it is imperative to identify promising treatment targets. In this study, we aimed to explore the incidence of AE when administering radiotherapy to patients with oligoprogressive solid tumours while they are undergoing treatment with immune checkpoint inhibitors (ICIs). MATERIALS AND METHODS: In this multicentre prospective observational study, oligoprogressive disease was defined as a < 20% increase in lesions compared to > 2 months before enrolment. We enrolled patients who requested radiotherapy during the ICI rest period between 2020 and 2023. AE was considered present if ≥ 1 non-irradiated lesion decreased by ≥ 30% before the next line of systemic therapy started. RESULTS: Twelve patients were included in this study; the common primary lesions were in the lungs (four patients) and kidneys (three patients). AEs were observed in six (50%) patients, with a median time to onset of 4 (range 2-9) months after radiotherapy. No significant predictors of AEs were identified. Patients in the AE group had a significantly better 1-year progression-free survival (PFS) rate than those in the non-AE group (p = 0.008). Two patients from the AE group were untreated and progression-free at the last follow-up. Four (33%) patients experienced grade 2 toxicity, with two cases attributed to radiotherapy and the other two to ICI treatment. No grade 3 or higher toxicities were observed in any category. CONCLUSION: Patients with oligoprogressive disease may be promising targets with potential for AEs. AEs can lead to improved PFS and, in rare cases, to a certain progression-free period without treatment. Irradiating solid tumours in patients with oligoprogressive disease during immune checkpoint inhibitor therapy may be a promising target with the potential for abscopal effects (AEs). AEs can lead to improved progression-free survival and, in rare cases, to a certain progression-free period without treatment.

SCD1 inhibition enhances the effector functions of CD8+ T cells via ACAT1-dependent reduction of esterified cholesterol.

We previously reported that the inhibition of stearoyl-CoA desaturase 1 (SCD1) enhances the antitumor function of CD8+ T cells indirectly via restoring production of DC recruiting chemokines by cancer cells and subsequent induction of antitumor CD8+ T cells. In this study, we investigated the molecular mechanism of direct enhancing effects of SCD1 inhibitors on CD8+ T cells. In vitro treatment of CD8+ T cells with SCD1 inhibitors enhanced IFN-γ production and cytotoxic activity of T cells along with decreased oleic acid and esterified cholesterol, which is generated by cholesterol esterase, acetyl-CoA acetyltransferase 1 (ACAT1), in CD8+ T cells. The addition of oleic acid or cholesteryl oleate reversed the enhanced functions of CD8+ T cells treated with SCD1 inhibitors. Systemic administration of SCD1 inhibitor to MCA205 tumor-bearing mice enhanced IFN-γ production of tumor-infiltrating CD8+ T cells, in which oleic acid and esterified cholesterol, but not cholesterol, were decreased. These results indicated that SCD1 suppressed effector functions of CD8+ T cells through the increased esterified cholesterol in an ACAT1-dependent manner, and SCD1 inhibition enhanced T cell activity directly through decreased esterified cholesterol. Finally, SCD1 inhibitors or ACAT1 inhibitors synergistically enhanced the antitumor effects of anti-PD-1 antibody therapy or CAR-T cell therapy in mouse tumor models. Therefore, the SCD1-ACAT1 axis is regulating effector functions of CD8+ T cells, and SCD1 inhibitors, and ACAT1 inhibitors are attractive drugs for cancer immunotherapy.

Preventive effect of intermittent cerebrospinal fluid drainage for secondary chronic hydrocephalus after aneurysmal subarachnoid hemorrhage.

BACKGROUND: The efficacy of intermittent cerebrospinal fluid (CSF) drainage compared with that of continuous CSF drainage in patients with subarachnoid hemorrhage (SAH) remains undetermined to date. Therefore, we investigated whether intermittent CSF drainage is effective in reducing secondary chronic hydrocephalus (sCH) after aneurysmal SAH. METHODS: Overall, 204 patients (69 men and 135 women) treated for aneurysmal SAH between 2007 and 2022 were included in this study. Following SAH onset, 136 patients were managed with continuous CSF drainage, whereas 68 were managed with intermittent CSF drainage. Logistic regression analyses were used to calculate the age-adjusted and multivariate odds ratios for the development of sCH. The Cox proportional hazards regression model were used to compare the effects of intermittent and continuous CSF drainage on sCH development. RESULTS: Overall, 96 patients developed sCH among the 204 patients with SAH. In total, 74 (54.4%) of the 136 patients managed with continuous CSF drainage developed sCH, whereas 22 (32.4%) of the 68 patients managed with intermittent CSF drainage developed sCH. This demonstrated that the rate of sCH development was significantly lower among patients managed with intermittent CSF drainage. Compared with continuous CSF drainage, intermittent CSF drainage exhibited a multivariate odds ratio (95% confidential interval) of 0.25 (0.11-0.57) for sCH development. Intermittent CSF drainage was more effective (0.20, 0.04-0.95) in patients with severe-grade SAH than in those with mild-grade SAH (0.33, 0.12-0.95). Intermittent CSF drainage was ineffective in patients with acute hydrocephalus (8.37, 0.56-125.2), but it was effective in patients without acute hydrocephalus (0.11, 0.04-0.31). CONCLUSIONS: Compared with continuous CSF drainage, intermittent drainage is more effective in reducing sCH after aneurysmal SAH. Although intermittent drainage was ineffective in cases of co-occurrence of acute hydrocephalus, it was effective in reducing sCH development regardless of the severity of initial symptoms at SAH onset.

Reversible Bilateral Transverse Sinus Occlusion Treated by Lumboperitoneal Shunt in Idiopathic Intracranial Hypertension: A Case Report.

We report a patient with idiopathic intracranial hypertension (IIH) with bilateral transverse sinus occlusion treated by a lumboperitoneal shunt. A 45-year-old woman presented with visual disturbance and chronic headache. Magnetic resonance (MR) venography and three-dimensional computed tomography angiography (3D-CTA) showed occlusion of both transverse sinuses. After the surgery, MR venography and 3D-CTA showed no blockages in both transverse sinuses. This phenomenon reveals that obstruction of the bilateral transverse sinus is a consequence of intracranial hypertension, not just a single cause. Since many patients have an obstruction or stenosis of the venous sinus, there are some reports of endovascular treatment. Sinus reconstruction is usually effective, but it is not effective in some cases. Reversal of sinus occlusion suggests that endovascular therapy for IIH is inadequate in some cases.

Phase I and II randomized clinical trial of an oral therapeutic vaccine targeting human papillomavirus for treatment of cervical intraepithelial neoplasia 2 and 3.

BACKGROUND: Although many human papillomavirus (HPV)-targeted therapeutic vaccines have been examined for efficacy in clinical trials, none have been translated into clinical use. These previous agents were mostly administered by intramuscular or subcutaneous injection to induce systemic immunity. We investigated the safety and therapeutic efficacy of an HPV-16 E7-expressing lacticaseibacillus-based oral vaccine. METHODS: In a double-blind, placebo-controlled, randomized trial, a total of 165 patients with HPV-16-positive high-grade cervical intraepithelial neoplasia 2 and 3 were assigned to orally administered placebo or low, intermediate, or high doses of IGMKK16E7 (lacticaseibacillus paracasei expressing cell surface, full-length HPV-16 E7). In the 4 groups, IGMKK16E7 or placebo was administered orally at weeks 1, 2, 4, and 8 postenrollment. The primary outcomes included histopathological regression and IGMKK16E7 safety. RESULTS: In per-protocol analyses, histopathological regression to normal (complete response) occurred in 13 (31.7%) of 41 high-dose recipients and in 5 (12.5%) of 40 placebo recipients (rate difference = 19.2, 95% confidence interval [CI] = 0.5 to 37.8). In patients positive for HPV-16 only, the clinical response rate was 40.0% (12 of 30) in high-dose recipients and 11.5% (3 of 26) in recipients of placebo (rate difference = 28.5, 95% CI = 4.3 to 50.0). There was no difference in adverse events that occurred in the high-dose and placebo groups (P = .83). The number of HPV-16 E7-specific interferon-γ producing cells within peripheral blood increased with level of response (stable disease, partial, and complete responses; P = .004). The regression to normal (complete response) rates among recipients with high levels of immune response were increased in a dose-dependent manner. CONCLUSION: This trial demonstrates safety of IGMKK16E7 and its efficacy against HPV-16-positive cervical intraepithelial neoplasia 2 and 3. IGMKK16E7 is the first oral immunotherapeutic vaccine to show antineoplastic effects. TRIAL REGISTRATION: jRCT2031190034.

Factors associated with early discontinuation of anamorelin in patients with cancer-associated cachexia.

PURPOSE: Cancer-associated cachexia, a multifactorial syndrome involving loss of muscle mass and anorexia, is an unremitting problem for cancer patients. Anamorelin has become available for cancer-associated cachexia, but early discontinuation is common in clinical practice. This study aimed to explore factors related to the early discontinuation of anamorelin and its relationship to survival. PATIENTS AND METHODS: This prospective, observational study of multimodal clinical practice involved patients who took anamorelin (100 mg) for cancer-associated cachexia at Aichi Medical University Hospital between 14 May 2021 and 31 March 2022. In July 2022, clinical data were extracted from electronic clinical records. Patients who discontinued anamorelin less than 4 weeks after initiation were defined as the early discontinuation group, and their clinical data and survival time were compared with those of the continuation group. This study was approved by the Ethics Committee of the university (approval no. 2021-124). RESULTS: Of the 42 patients treated with anamorelin, 40 (median age 72.5 years, median BMI 18.7 kg/m2) were analyzed, including 13 with non-small cell lung cancer, and 12 with pancreatic, 8 with colorectal, and 7 with gastric cancers. On univariate analysis, the early discontinuation group included more patients with worse performance status (PS) (p=0.028), low prognostic nutritional index (PNI) (p=0.001), and no concomitant anticancer drugs (p=0.003). On multivariate analysis, PS and PNI were related to anamorelin continuation. Survival time was significantly shorter in the early discontinuation group (p=0.039). CONCLUSION: Worse PS and low PNI were associated with early discontinuation of anamorelin. Longer survival time was observed in the continuation group.

Intra-Patient Genomic Variations of Human Papillomavirus Type 31 in Cervical Cancer and Precancer.

Human papillomavirus type 31 (HPV31) is detected less frequently in cervical cancer than two major causative types, HPV16 and HPV18. Here, we report a comprehensive analysis of HPV31 genome sequences in cervical lesions collected from Japanese women. Of 52 HPV31-positive cervical specimens analyzed by deep sequencing, 43 samples yielded complete genome sequences of around 7900 base pairs and 9 samples yielded partially deleted genome sequences. Phylogenetic analysis showed that HPV31 variant distribution was lineage A in 19 samples (36.5%), lineage B in 28 samples (53.8%), and lineage C in 5 samples (9.6%), indicating that lineage B variants are dominant among HPV31 infections in Japan. Deletions in the viral genome were found in the region from the E1 to L1 genes, but all the deleted genomes retained the E6/E7 genes. Among intra-patient nucleotide variations relative to a consensus genome sequence in each sample, C-to-T substitutions were most frequently detected, followed by T-to-C and C-to-A substitutions. High-frequency, intra-patient mutations (>10%) in cervical cancer samples were found in the E1, E2, and E7 genes, and all of them were nonsynonymous substitutions. The enrichment of high-frequency nonsynonymous substitutions strongly suggests that these intra-patient mutations are positively selected during the development of cervical cancer/precancer.

Serum Free Fatty Acid Changes Caused by High Expression of Stearoyl-CoA Desaturase 1 in Tumor Tissues Are Early Diagnostic Markers for Ovarian Cancer.

Ovarian cancer has a poor prognosis and is difficult to detect in early stages. Therefore, developing new diagnostic markers for early-stage ovarian cancer is critical. Here, we developed a diagnostic marker for early-stage ovarian cancer on the basis of fatty acid metabolism characteristics of cancer cells. The expression of various fatty acid metabolizing enzymes such as stearoyl-CoA desaturase 1 (SCD1) was altered in early-stage ovarian cancer tissue compared with that in normal ovarian tissue. Changes in the expression of fatty acid metabolizing enzymes, particularly SCD1, in cancer tissues were found to alter concentrations of multiple free fatty acids (FFA) in serum. We were the first to show that fatty acid metabolic characteristics in tissues are related to the FFA composition of serum. Surprisingly, patients with stage I/II ovarian cancer also showed significant changes in serum levels of eight FFAs, which can be early diagnostic markers. Finally, using statistical analysis, an optimal early diagnostic model combining oleic and arachidic acid levels, fatty acids associated with SCD1, was established and confirmed to have higher diagnostic power than CA125, regardless of histology. Thus, our newly developed diagnostic model using serum FFAs may be a powerful tool for the noninvasive early detection of ovarian cancer. SIGNIFICANCE: Measurement of serum FFA levels by changes in the expression of fatty acid metabolizing enzymes in tumor tissue would allow early detection of ovarian cancer. In particular, the SCD1-associated FFAs, oleic and arachidic acid, would be powerful new screening tools for early-stage ovarian cancer.

Human papillomavirus vaccine impact on invasive cervical cancer in Japan: Preliminary results from cancer statistics and the MINT study.

The first prophylactic vaccine against human papillomavirus (HPV) 16 and HPV18 was licensed in Japan in 2009. HPV vaccine effectiveness against high-grade cervical lesions has been demonstrated among young Japanese women, but evidence of its effects on invasive cervical cancer (ICC) is lacking. Using data from two different cancer registries, we compared recent trends of new ICC cases by age group using Poisson regression analysis. We also analyzed time trends in HPV16/18 prevalence among 1414 Japanese women aged <40 years newly diagnosed with ICC in the past decade. Based on the population-based cancer registry, the incidence of ICC among young women aged 20-29 years showed a significant decline from 3.6 to 2.8 per 100 000 women-years during 2016-2019, but no similar decline was observed for older age groups (p < 0.01). Similarly, using data from the gynecological cancer registry of the Japan Society of Obstetrics and Gynecology, the annual number of ICCs among women aged 20-29 years also decreased from 256 cases to 135 cases during 2011-2020 (p < 0.0001). Furthermore, a declining trend in HPV16/18 prevalence in ICC was observed only among women aged 20-29 years during 2017-2022 (90.5%-64.7%, p = 0.05; Cochran-Armitage trend test). This is the first report to suggest population-level effects of HPV vaccination on ICC in Japan. Although the declining trend in HPV16/18 prevalence among young women with ICC supports a causal linkage between vaccination and results from cancer registries, further studies are warranted to confirm that our findings are attributable to vaccination.

Clinical availability and characteristics of multigene panel testing for recurrent/advanced gynecologic cancer.

BACKGROUND: Japan's health insurance covers multigene panel testing. This study aimed to determine the potential availability and utility of gene panel testing clinically in gynecologic oncology. METHODS: We analyzed the characteristics of patients with gynecologic cancer who underwent gene panel testing using FoundationOne® CDx or OncoGuide™ NCC Oncopanel between November 2019 and October 2022. RESULTS: Out of 102 patients analyzed, 32, 18, 43, 8, and 1 had cervical, endometrial, ovarian cancers, sarcoma, and vaginal cancer, respectively. Druggable gene alteration was found in 70 patients (68.6%; 21 with cervical cancer, 15 with endometrial cancer, 28 with ovarian cancer, 5 with sarcoma, and 1 with other). The most common druggable gene alteration was PIK3CA mutation (n = 21), followed by PTEN mutation (n = 12) and high tumor mutation burden (TMB-H) (n = 11). TMB-H was detected in 5 patients with cervical cancer, 5 with endometrial cancer, and 1 with endometrial stromal sarcoma. Eleven patients (10.8%) received molecularly targeted therapy according to their gene aberrations. Gene panel testing was mostly performed when the second-line treatment was ineffective. Of all 102 patients, 60 did not have recommended treatment, and 15 died or had worsened conditions before obtaining the test results. CONCLUSION: Through multigene panel testing, although many patients had druggable gene alterations, 10.8% of them received the recommended treatment. TMB-H was mainly observed in cervical/endometrial cancer, suggesting its potential as a therapeutic biomarker of immune checkpoint inhibitors. Furthermore, patients' prognosis and performance status should be considered before performing the test.

Successful radiotherapy for recurrent obstructive pancreatitis secondary to pancreatic metastasis from cervical squamous-cell carcinoma.

Metastatic pancreatic cancer is a rare condition and cases of pancreatic metastasis from cervical cancer are infrequently reported. Furthermore, the incidence rates of pancreatic tumors as the cause of pancreatitis and of pancreatitis in patients with pancreatic tumors are similarly low. Pancreatitis may occur when a tumor obstructs the pancreatic duct. This condition may be difficult to manage and significantly reduces the quality of life because of severe abdominal pain. Here, we present a rare case of obstructive pancreatitis caused by pancreatic metastasis from cervical squamous-cell carcinoma, pathologically confirmed using endoscopic ultrasonography-guided fine-needle biopsy and treated with palliative irradiation to achieve rapid therapeutic relief. It is important to obtain appropriate tissue samples, confirm the pathological diagnosis, and compare the pathological findings with those of the primary tumor to select the appropriate treatment for obstructive pancreatitis caused by a metastatic pancreatic tumor.

Evaluation of CD4+ cells infiltration as a prognostic factor in cervical intraepithelial neoplasia 2.

OBJECTIVE: To identify candidate predictors for the prognosis of cervical intraepithelial neoplasia 2 (CIN2) lesions and evaluate the prognostic value of the local immune response. METHODS: One hundred fifteen CIN2 patients were enrolled. The percentage of p16-, minichromosome maintenance complex component 2- or apolipoprotein B mRNA editing enzyme catalytic subunit 3G (APOBEC3G)-positive cells was determined immunohistochemically. Tumor-infiltrating lymphocytes (TILs) in intertumoral lesions were scored using an automated system. CIN3 disease progression and regression rates were estimated by the Kaplan-Meier method. A case-control study was conducted to screen CIN2 prognostic factors in 10 regression and 10 progression patients. Selected factors were examined in a cohort study to determine their prognostic value for CIN2. RESULTS: Among all participants, the cumulative progression and regression rates at 60 months were 0.477 and 0.510, respectively. In the case-control study, p16- and APOBEC3G-positive cells were higher in the progression group (p=0.043, p=0.023). Additionally, CD4+ cell infiltration was enhanced in the regression group (p=0.023). The cohort study revealed a significantly increased progression rate in patients with elevated p16-positive cells (p<0.001), and increased CD4+ TIL infiltration was associated with better regression (p=0.011). Kaplan-Meier analysis according to human papillomavirus (HPV) positivity revealed a greater CIN3 development risk in HPV16-positive patients than in HPV16-negative cases. Finally, multivariate analysis identified HPV16 infection and CD4+ TIL infiltration as independent prognostic factors in CIN2 regression. CONCLUSION: CD4+ TIL infiltration in intertumoral lesions was related with CIN2 regression. Our findings suggest CD4+ TIL infiltration may be useful for the triage of CIN2 patients.

Whole-genome analysis of human papillomavirus 67 isolated from Japanese women with cervical lesions.

BACKGROUND: Human papillomavirus (HPV) type 67 is phylogenetically classified into Alphapapillomavirus species 9 (alpha-9) together with other carcinogenic types (HPV16, 31, 33, 35, 52 and 58), but is the only alpha-9 type defined as possibly carcinogenic. This study aimed to determine whole-genome sequences of HPV67 isolated from Japanese women with cervical cancer or cervical intraepithelial neoplasia (CIN) to better understand the genetic basis of the oncogenic potential of HPV67. METHODS: Total cellular DNA isolated from cervical exfoliated cells that were single positive for HPV67 (invasive cervical cancer, n = 2; CIN3, n = 6; CIN 2, n = 1; CIN1, n = 2; the normal cervix, n = 1) was subjected to PCR to amplify HPV67 DNA, followed by next generation sequencing to determine the complete viral genome sequences. Variant lineages/sublineages were assigned through viral whole-genome phylogenetic analysis. The transcriptional activity of the virus early promoter was assessed by luciferase reporter assays in cervical cancer cell lines. RESULTS: Phylogenetic analyses of HPV67 genomes from Japan (n = 12) revealed that 11 belonged to lineage A (sublineage A1, n = 9; sublineage A2, n = 2) and one belonged to lineage B. All cancer cases contained sublineage A1 variants, and one of these contained an in-frame deletion in the E2 gene. The long control region of the HPV67 genome did not induce transcription from the virus early promoter in HeLa cells, but showed weak transcriptional activity in CaSki cells. CONCLUSIONS: The single detection of HPV67 in cervical cancer and precancer specimens strongly suggests the carcinogenic potential of this rare genotype. The phylogenetic analysis indicates a predominance of lineage A variants among HPV67 infections in Japan. Since only 23 complete genome sequences of HPV67 had been obtained until now, the newly determined genome sequences in this study are expected to contribute to further functional and evolutionary studies on the genetic diversity of HPV67.

Anti-inflammatory and nutritional improvement effects of dietary supplementation combined with fish oil in patients with epithelial cancer.

The present study investigated the effects of dietary supplementation combined with fish oil containing relatively low levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on the inflammatory and nutritional status of patients with epithelial cancer. Fish oil capsules (498 mg EPA and 213 mg DHA) and dietary supplements (100 kcal and 5 g protein) were administered for 8 weeks to 20 patients with cancer and inflammation [C-reactive protein (CRP) ≥0.30 mg/dl]. Blood EPA levels increased significantly after 4 and 8 weeks, while no significant differences were observed in log-transformed (log) CRP levels, which were the major inflammatory indices in these patients. A declining trend was observed at 8 weeks after excluding 2 patients with suspected infection (P=0.06). A significant increase was observed from week 0 to week 8 for log interleukin-6 (IL-6) levels. After excluding the 2 patients with suspected infection, no significant difference was observed when comparing week 0 to week 8 for log IL-6. No deterioration in albumin or pre-albumin levels was observed. These results suggest that although suppression of acute inflammation associated with infection is difficult, intake of relatively low EPA and DHA supplements may be effective for mild chronic inflammation in patients with epithelial cancer without infection. Large-scale randomized clinical trials are required to make the final decision regarding efficacy. The study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR; 06/07/2018, UMIN000033309).

Regional differences in human papillomavirus type 52 prevalence among Japanese women with cervical intraepithelial neoplasia†.

Although geographical differences in the distribution of human papillomavirus genotypes have been observed worldwide, no studies have reported on national differences in the prevalence of human papillomavirus types in Japan. Here, we report a cross-sectional study to explore regional differences in the prevalence of human papillomavirus types among Japanese women with cervical intraepithelial neoplasia or invasive cervical cancer. Using human papillomavirus genotyping data from the nationwide prospective study on human papillomavirus vaccine effectiveness, we compared the frequency of detection of 15 high-risk and two low-risk human papillomavirus types in each disease category between the women who visited hospitals located in eastern Japan and those who visited hospitals located in western Japan. The risk of cervical intraepithelial neoplasia progression was assessed by calculating a prevalence ratio of each human papillomavirus type for cervical intraepithelial neoplasia grade 2/3 versus grade 1. Among the human papillomavirus types studied, human papillomavirus 52 was detected significantly more frequently in western hospitals than in eastern hospitals in cervical intraepithelial neoplasia grade 1 patients, but was less frequent in cervical intraepithelial neoplasia grade 2/3. The prevalence of particular human papillomavirus types was not significantly different between patients in hospitals in eastern Japan and those in hospitals in western Japan for invasive cervical cancer. In both eastern and western hospitals, a higher risk of cervical intraepithelial neoplasia progression was observed in patients infected with human papillomavirus 16, 31 or 58. In contrast, there was a significantly higher prevalence of human papillomavirus 52 infection in women with cervical intraepithelial neoplasia grade 2/3 than in those with cervical intraepithelial neoplasia grade 1 in eastern hospitals (prevalence ratio, 1.93; 95% confidence interval, 1.48-2.58), but not in western hospitals (prevalence ratio, 1.03; 95% confidence interval, 0.83-1.30). Regional differences of human papillomavirus 52 prevalence in cervical intraepithelial neoplasia lesions may exist and emphasize the importance of continuous monitoring of human papillomavirus type prevalence throughout the country in order to accurately assess the efficacy of human papillomavirus vaccines.

Inhibition of stearoyl-CoA desaturase 1 (SCD1) enhances the antitumor T cell response through regulating ß-catenin signaling in cancer cells and ER stress in T cells and synergizes with anti-PD-1 antibody.

BACKGROUND: Understanding the mechanisms of non-T cell inflamed tumor microenvironment (TME) and their modulation are important to improve cancer immunotherapies such as immune checkpoint inhibitors. The involvement of various immunometabolisms has recently been indicated in the formation of immunosuppressive TME. In this study, we investigated the immunological roles of stearoyl-CoA desaturase 1 (SCD1), which is essential for fatty acid metabolism, in the cancer immune response. METHODS: We investigated the roles of SCD1 by inhibition with the chemical inhibitor or genetic manipulation in antitumor T cell responses and the therapeutic effect of anti-programmed cell death protein 1 (anti-PD-1) antibody using various mouse tumor models, and their cellular and molecular mechanisms. The roles of SCD1 in human cancers were also investigated by gene expression analyses of colon cancer tissues and by evaluating the related free fatty acids in sera obtained from patients with non-small cell lung cancer who were treated with anti-PD-1 antibody. RESULTS: Systemic administration of a SCD1 inhibitor in mouse tumor models enhanced production of CCL4 by cancer cells through reduction of Wnt/ß-catenin signaling and by CD8+ effector T cells through reduction of endoplasmic reticulum stress. It in turn promoted recruitment of dendritic cells (DCs) into the tumors and enhanced the subsequent induction and tumor accumulation of antitumor CD8+ T cells. SCD1 inhibitor was also found to directly stimulate DCs and CD8+ T cells. Administration of SCD1 inhibitor or SCD1 knockout in mice synergized with an anti-PD-1 antibody for its antitumor effects in mouse tumor models. High SCD1 expression was observed in one of the non-T cell-inflamed subtypes in human colon cancer, and serum SCD1 related fatty acids were correlated with response rates and prognosis of patients with non-small lung cancer following anti-PD-1 antibody treatment. CONCLUSIONS: SCD1 expressed in cancer cells and immune cells causes immunoresistant conditions, and its inhibition augments antitumor T cells and therapeutic effects of anti-PD-1 antibody. Therefore, SCD1 is an attractive target for the development of new diagnostic and therapeutic strategies to improve current cancer immunotherapies including immune checkpoint inhibitors.