Virus-augmented delayed hypersensitivity skin tests in gynecological malignancies

Summary Cultured human tumor cells of various histologic origins were infected with PR8/A/34 influenza virus. Nonviable crude membrane extracts were derived from the infected and uninfected cells. The extracts were coded and tested for their ability to produce delayed hypersensitivity skin reactions (DHSR) in allogeneic patients with squamous uterine cervical carcinoma, epithelial ovarian carcinoma, and malignant melanoma. Augmented antigen sensitivity to the virus-modified extracts compared with virus alone or to the unmodified extracts was observed in all patient groups. There was insufficient specificity to delineate a response by individual tumor type and related tumor extract, but some of the observed responses suggested tumor or organ site associations. Cervical carcinoma patients reacted more frequently to the virus-modified cervix extract, which also produced a high frequency of response in patients with ovarian carcinoma and melanoma. Ovarian carcinoma patients demonstrated increased sensitivity to both virus-modified ovarian carcinoma extracts, although 14 of 21 patients also showed responsiveness to one of the unmodified ovarian extracts. Malignant melanoma patients showed increased sensitivity to all virus-modified extracts except one of two derived from the ovarian carcinoma, and demonstrated a significantly augmented response to the virus-modified melanoma extract when the response to this extract was compared with that in ovarian carcinoma patients.The augmented reactions appear to be due to an association of the PR8 virus and as yet undetermined cellular components rather than to the virus alone. The possible involvement of tumor-associated determinants and the clinical significance of this phenomenon require further investigation.     

A Folate Binding Protein in Ascitic Fluid, Serum and Ovarian Tissue of Patients with Ovarian Adenocarcinoma Immunoreacts with Antibodies Against Human Milk Folate Binding Protein

The presence of a folate binding protein which immunoreacts with antibodies against human milk folate binding protein was demonstrated in ascitic fluids from seven patients with ovarian adenocarcinoma. Ascitic fluids collected from two patients with other malignancies contained non-immunoreactive FBP. Tumor tissue specimens from five patients with ovarian carcinoma contained immunoreactive FBP. By contrast to normal ovaries ovarian carcinoma tissue showed positive immunostaining on immunohistochemistry. Ascitic fluids from two patients with ovarian carcinoma exhibited single distinct bands on SDS-PAGE immunoblotting. The gel filtration profile of ovarian carcinoma tissue homogenate from two patients contained 25 and 100 kDa peaks of radioligand-bound and immunoreactive folate binding protein, while ascitic fluid from one of the patients exhibited a large 100 kDa immunoreactive peak with no radioligand binding activity. The immunoreactive non-functional 100 kDa FBP could represent unprocessed precursor FBP. Future studies are necessary to evaluate whether determination of immunoreactive FBP in ovarian adenocarcinomatosis is of any diagnostic value.     

Comparison of cellular phenotypes in tumor cyst and ascitic fluid from ovarian serous carcinoma.

Density gradient centrifugation was applied to isolate cell subsets from tumor cyst and ascitic fluid in eight patients with ovarian serous carcinoma. A comparison of cellular composition and immunologic reactivity of cells from the cysts and from ascitic fluid in each patient was performed. Some differences in density profiles were found, but in each case the consistency of morphologic cell forms in the primary tumor and ascites was documented. Immunophenotypic analyses of isolated cellular fractions using polyclonal and monoclonal antibodies against ovarian carcinoma-associated antigens showed significant immunologic intratumoral heterogeneity. However, there was a similarity of antigen expression in cells from the primary tumors and ascitic fluids. Our study indicated that morphologic and antigenic characterization of a given tumor could be determined in a single representative sample of ascitic fluid.     

Density distribution, cytomorphologic features and immunologic characteristics of ovarian and endometrial clear cell carcinomas

Three subpopulations of cancer cells with different morphologic features were separated by density gradient centrifugation of two ascitic fluids and one cystic fluid from one patient with ovarian clear cell carcinoma and one with endometrial clear cell carcinoma. Immunophenotypic analyses of isolated fractions using polyclonal and monoclonal antibodies against ovarian carcinoma-associated antigens revealed significant immunologic heterogeneity among the tumor cells. The identical histopathologic structures of the ovarian and endometrial clear cell carcinomas and the similar distribution and immunologic reactivity of the cell types isolated from the ascitic and cystic fluids confirmed the common histogenesis of both cancers. These findings suggest that the conventional cytologic diagnosis of clear cell carcinomas could be supplemented by immunofluorescent staining. Density gradient centrifugation appeared to be a useful method for the separation of mesothelial cells.     

Effect of virus-modified tumor cell extracts,autologous mononuclear cell infusions and interleukin-2 on oncolytic activity of effector cells of patients with advanced ovarian cancer

Summary We studied the biological responses of six ovarian cancer patients after intraperitoneal (i.p.) injections of virus-modified tumor cell extracts (VMTE) and autologous peripheral blood mononuclear cells, collected by leukapheresis after two injections of VMTE. VMTE was prepared from allogeneic ovarian cell lines, OV2774 and CaOV3, modified by influenza virus, A/PR8/34. A dose of 9 mg VMTE was given i.p. in total of 2–4 injections, and (1–9) × 10⁸ autologous mononuclear cells were infused i.p., 24 h after the second VMTE injection, and 24 h and 72 h after the third VMTE injection. Both peripheral blood (PB) and peritoneal cavity (PC) effector cell cytotoxicity was significantly enhanced against the K562 cell line in the majority of patients, 24–48 h after the second and third VMTE injections. This was accompanied by a dramatic influx of neutrophils into PC (57-550-fold), increase in absolute numbers of lymphocytes, (including large granular lymphocytes) and monocytes, and resulted also in a significant decrease in the number of ascitic tumor cells (98% reduction). The infusion of autologous mononuclear cells did not appear to influence either cytotoxicity or cell infiltration of the peritoneal cavity. We also investigated the in vitro effect of recombinant interleukin-2 (IL-2) on effector cells from PB and PC from patients before and after VMTE treatment. Cytotoxicity of both of these compartments was significantly potentiated after culture with IL-2. In three out of five VMTE-treated patients, PC cytotoxicity was significantly higher after activation with IL-2 than that of patients before VMTE treatment. These data suggest that VMTE induces regional cellular immunity, which could be further potentiated by culture of PC effector cells with IL-2. Thus, combination of VMTE and IL-2 after regional administration could represent the effective therapy for patients with advanced ovarian cancer.     

Peritoneal fluids from patients with certain gynecologic tumor contain elevated levels of bioactive lysophospholipase D activity

Levels of lysophosphatidic acid (LPA), an important phospholipid mediator, in serum and ascitic fluid from ovarian cancer patients were shown to be higher than those from healthy women and from patients with other type of cancer, respectively. Although LPA in human serum seems mainly to be generated by lysophospholipase D (lysoPLD), the source and pathway for LPA in the ascitic fluid remain still obscure. In this study, we examined whether lysoPLD activity producing bioactive LPA in human peritoneal fluid was significantly elevated under pathological statuses. Lysophospholipase D activity in human peritoneal fluids was measured by quantifying choline released from exogenous lysophosphatidylcholine on their incubation at 37 degrees C. We also compared the activity of lysoPLD in sera from patients with different gynecologic diseases. We found relatively high lysoPLD activity in peritoneal fluids from patients with ovarian cancer, dermoid cyst or mucinous cystadenoma, whereas there were no significant differences in the serum lysoPLD activity among clinical groups and healthy subjects. The lysoPLD in the peritoneal fluid was found to have similar substrate specificity and metal ion requirement to those of serum lysoPLD, that has been identified as autotaxin, a tumor cell-motility stimulating protein. Our results suggest that increased lysoPLD activity in peritoneal fluid from patients with certain gynecologic tumors might be relevant to its potential of tumor progression.     

Interleukin-15 enhances natural killer cell cytotoxicity in patients with acute myeloid leukemia by upregulating the activating NK cell receptors

Interleukin-15 (IL-15) has a major role in NK-cell homeostasis. Modulation of the relative frequency and expression intensity of the NK-cell receptors by IL-15 may increase NK cell-mediated cytotoxicity in cancer patients. We investigated the receptor repertoire and measured NK-cell activity in newly diagnosed AML patients and evaluated the ex vivo effects of IL-15. The expression of the activating NK cell receptors was significantly decreased in the AML patients compared to that in NK cells of healthy donors. When NK cells obtained from AML patients were cultured with IL-15, expression of the activating receptors was significantly upregulated compared to pre-culture levels. Concomitantly, cytotoxic activity of NK cells against autologous leukemic blasts increased following IL-15 stimulation. This IL-15 induced increase in activity was blocked by neutralizing antibodies specific for the NK cell activating receptors. These pre-clinical data support the future use of IL-15 for NK cell- based therapies for AML patients.     

Role of human circulating and tumor-infiltrating lymphocytes in cancer defense and treatment

We have analyzed the anticancer efficacy of various subsets of human circulating and tumor-infiltrating lymphocytes (TIL). These studies showed that circulating natural killer (NK) cells mediate the most potent oncolytic activity against a variety of tumor targets, after enrichment or stimulation with interleukin-2 (IL-2). Interestingly, NK cell oncolytic activity was directed also against tumor targets frequently designated as 'NK-resistant'. This indicates that NK cells display a broader spectrum of killing than is commonly recognized. TIL did not display any tumoricidal activity when unstimulated, but acquired cytotoxic potential after activation with IL-2. Comparative studies of TIL and circulating lymphocytes from patients with ovarian cancer demonstrated that these two groups of lymphocytes manifested similar levels of cytotoxicity and the same spectrum of target cell killing. No specificity in autologous tumor cell killing was displayed by TIL; instead, TIL were effective against autologous as well as allogeneic tumor targets. The lack of TIL tumor specificity was not detected only in ovarian tumors, but was manifested also in renal- and squamous-cell cancers. Characterization studies demonstrated that the primary oncolytic cells in the periphery and among TIL are NK cells. T lymphocytes displayed some, but rather negligible cytotoxic activity. In contrast, when IL-2-activated NK and T cells were analyzed for lytic activity against normal hematopoietic cells, T cells displayed high levels of bone marrow killing. The anti-bone marrow lytic activity of IL-2-activated T lymphocytes may be harmful after therapy with conventionally prepared lymphokine-activated killers. In light of these observations, new directions to adoptive immunotherapy are discussed.     

Depression of murine natural killer cell cytotoxicity by isobutyl nitrite

Summary We have investigated the effect of isobutyl nitrite on murine NK-cell antitumor-directed cytotoxicity. This agent has been suggested as one of the factors underlying immunodeficiency syndrome (AIDS) in man. We demonstrated that two injections, each of 0.25 ml isobutyl nitrite, resulted in significant depression of endogenous splenic and peripheral blood natural killer (NK) cell cytotoxicity against T-cell lymphoma, YAC-1. In addition to endogenous NK cells, activity of pyrimidinol-activated NK cells was also substantially depressed by this agent. The latter observation is of the utmost importance, since it suggests that the attempt to augment NK-cell activity (to promote resistance to infections and malignancies) could fail in patients with AIDS who are isobutyl nitrite users. Isobutyl nitrite was NK-cell-suppressive not only after in vivo administration but, most importantly, also after inhalation. This indicates that isobutyl nitrite, via its NK-cell suppressive effect, could contribute to immunodeficiency in AIDS. Studies on the mechanism of NK-cell depression by isobutyl nitrite demonstrated that the NK-cell tumor-binding properties as well as NK-cell cytotoxic potential were substantially depressed. Mixing experiments failed to reveal any regulation by suppressor cell activities. The results of these studies clearly indicate that isobutyl nitrite is an immunosuppressive agent and that its use should be avoided. Abbreviations used: NK, natural killer; S-RPMI 1640, supplemented tissue culture medium 1640; HEPES, N-2-hydroxyethylpiperazine-N-2-ethanesulfonic acid; TBC, tumor-binding cells; C-TBC, cytotoxic tumor-binding cells; AIPP, 2-amino-5-iodo-6-phenyl-4 pyrimidinol; LU, lytic units; T:E, target-to-effector; AIDS, acquired immunodeficiency syndrome     

Impaired local natural killer cell activity in human colorectal carcinomas

Summary The present study was undertaken to study natural killer (NK) cell activity in patients with colorectal cancer at peripheral and local levels. Mononuclear cells were isolated from uninvolved colorectal mucosa, tumor tissue and peripheral blood, and tested against the colon carcinoma cell line CaCo-2 and the erythroleukemia cell line K-562. Peripheral blood NK cell activity from the patients showed similar levels compared with healthy controls, whereas, mononuclear cells of tumor tissue were found to have a significantly decreased NK cell activity compared to the normal intestinal mucosa (P<0.01). No relation was found between the NK cell activity and the advancement of the disease according to the Duke's stage. Interferon- (IFN-) stimulated the NK cell activity of the mononuclear cells from blood, mucosa and tumor. However, the increase of NK cell activity after IFN- stimulation was lower in the tumor compared to the mucosa (P<0.02). The lectin, phytohaemagglutinin, increased the cytotoxicity of mononuclear cells from blood, mucosa and tumor to a similar level. These results suggest that patients with colorectal tumors exhibit a normal NK cell activity in peripheral blood and intestinal mucosa; however, a diminished NK cell activity exists at the tumor level. Although mononuclear cells isolated from the tumor have a normal response to lectin stimulation they show hyporesponsiveness to IFN- stimulation with regard to their NK cell activity.     

Intraperitoneal delivery of human natural killer cells for treatment of ovarian cancer in a mouse xenograft model

Background aimsThere is an urgent need for novel therapeutic strategies for relapsed ovarian cancer. Dramatic clinical anti-tumor effects have been observed with interleukin (IL)-2 activated natural killer (NK) cells; however, intravenous delivery of NK cells in patients with ovarian cancer has not been successful in ameliorating disease. We investigated in vivo engraftment of intraperitoneally (IP) delivered NK cells in an ovarian cancer xenograft model to determine if delivery mode can affect tumor cell killing and circumvent lack of NK cell expansion.MethodsAn ovarian cancer xenograft mouse model was established to evaluate efficacy of IP-delivered NK cells. Tumor burden was monitored by bioluminescent imaging of luciferase-expressing ovarian cancer cells. NK cell persistence, tumor burden and NK cell trafficking were evaluated. Transplanted NK cells were evaluated by flow cytometry and cytotoxicity assays.ResultsIP delivery of human NK cells plus cytokines led to high levels of circulating NK and was effective in clearing intraperitoneal ovarian cancer burden in xenografted mice. NK cells remained within the peritoneal cavity 54 days after injection and had markers of maturation. Additionally, surviving NK cells were able to kill ovarian cancer cells at a rate similar to pre-infusion levels, supporting that in vivo functionality of human NK cells can be maintained after IP infusion.ConclusionsIP delivery of NK cells leads to stable engraftment and antitumor response in an ovarian cancer xenograft model. These data support further pre-clinical and clinical evaluation of IP delivery of allogeneic NK cells in ovarian cancer.     

Positive effusion cytology as the initial presentation of malignancy

During a period of four years (1981 to 1984), 641 ascitic, 860 pleural and 47 pericardial fluid specimens were examined cytologically. Of these, 154 ascitic samples, 174 pleural specimens and 10 pericardial effusions, obtained, respectively, from 108, 133 and 7 patients, were found to contain malignant cells. In 7 patients, ascites, and in 18 cases, pleural effusions were the first indication of cancer. None of the positive pericardial fluids was the initial presentation of malignancy. The cytologic findings and follow-up data on these 25 patients are the subject of this study. The most common type of neoplasm in these effusions was adenocarcinoma (86% of the ascitic and 78% of the pleural fluids). Most of the malignant neoplasms in ascitic fluids were derived from ovarian tumors (5 of 7) while those in pleural effusions came mainly from lung tumors (12 of 18). Mammary carcinoma, which was the most common malignant tumor found in cases of pleural effusions, did not present initially with an effusion in any of our cases. The cytologic diagnosis was confirmed in all cases by either biopsy or strong clinical evidence. The prognosis in patients who initially presented with an effusion was poor. All of the patients with an adequate follow-up died within 29 months in cases of ascites and within 19 months in cases of pleural effusions.     

Copper content in ascitic fluid is associated with angiogenesis and progression in ovarian cancer

BackgroundAscites is associated with the poor prognosis of malignant tumors. The biological importance of the changes in the content of trace elements in the ascitic fluid is unknown. Herein, we analyzed trace elements in the ascitic fluid of patients with ovarian tumors and used cultured cells to determine the copper (Cu)-induced changes in gene expression in ovarian cancer.MethodsInductively coupled plasma mass spectrometry (ICP-MS) was used to compare ascitic fluid trace element levels in patients with benign ovarian tumors (n = 22) and borderline/malignant tumors (n = 5) for primary screening. Cu levels were validated using atomic absorption spectrometry (AAS) in 88 benign, 11 borderline, and 25 malignant ovarian tumor patients. To confirm Cu-induced gene expression changes, microarray analysis was performed for Cu-treated OVCAR3, A2780, and Met5A cells. The vascular endothelial growth factor (VEGF) concentration in the cell supernatant or ascitic fluid (ovarian cancer samples) was measured using ELISA.ResultsICP-MS showed that Co, Ni, Cu, Zn, As, Se, and Mo levels significantly increased in patients with malignant/borderline ovarian tumors compared to those in patients with benign ovarian tumors. AAS showed that malignant ovarian tumors were independently associated with elevated levels of Cu in ascites adjusted for age, body mass index, alcohol, smoking, and supplement use (p < 0.001). Microarray analysis of both Cu-treated ovarian cancer cell lines OVCAR3 and A2780 and the mesothelial cell line Met-5A revealed the upregulation of the angiogenesis biological process. Real-time polymerase chain reaction and ELISA demonstrated that an increased Cu content significantly enhanced VEGF mRNA expression and protein secretion in OVCAR3, A2780, and Met-5A cells. VEGF levels and clinical stages of the tumors correlated with the ascitic fluid Cu content in patients with malignant ovarian tumors (correlation coefficient 0.445, 95 % confidence interval [CI]: 0.069–0.710, p = 0.023 and correlation coefficient 0.406, 95 % CI: 0.022–0.686, p = 0.040, respectively).ConclusionCu levels significantly increased in patients with malignant ovarian cancer. Cu induced angiogenic effects in ovarian cancer and mesothelial cells, which affected ascites fluid production. This study clarifies the link between elevated Cu in ascites and malignant ovarian tumor progression. Strategies to decrease Cu levels in the ascitic fluid may help downregulate VEGF expression, thereby improving the prognosis of ovarian malignancies.     

Cytotoxic T cell clones isolated from ovarian tumor-infiltrating lymphocytes recognize multiple antigenic epitopes on autologous tumor cells.

CTL clones were developed from tumor infiltrating lymphocytes (TIL) from the ascites of a patient with ovarian carcinoma by coculture of TIL with autologous tumor cells and subsequent cloning in the presence of autologous tumor cells. These CTL clones expressed preferential cytolytic activity against autologous tumor cells but not against allogeneic ovarian tumor cells and the NK-sensitive cell line K562. The cytolytic activity of these CTL against autologous tumors was inhibited by anti-TCR (WT31 mAb), anti-HLA class I, and anti-CD3 mAb but not by the NK function antibody Leu 11b. Cloning of the autologous tumor cells in vitro revealed that the CTL clones of the ovarian TIL expressed differential abilities to lyse autologous tumor cell clones. The specificity analysis of these autologous tumor specific CTL suggested that they recognize several antigenic determinants present on the ovarian tumor cells. Our results indicate the presence of at least three antigenic epitopes on the tumor cells (designated OVA-1A, OVA-1B, and OVA-1C), one of which (OVA-1C) is unstable. These determinants are present either simultaneously or separately, and six types of ovarian clones can be distinguished on the basis of their expression. These results indicate that CTL of the TIL detect intratumor antigenic heterogeneity. The novel heterogeneity identified within the ovarian tumor cells in this report may be of significance for understanding cellular immunity in ovarian cancer and developing adoptive specific immunotherapeutic approaches in ovarian cancer.     

Estrogen receptor concentration and social factors as predictors of natural killer cell activity in early-stage breast cancer patients. Confirmation of a model

Previous work of ours has demonstrated that a significant amount of natural killer (NK) activity variance after surgery in stage I and II breast cancer patients could be accounted for by both the estrogen receptor (ER) status of the tumor and by social factors, namely, perceived social support and seeking social support as a general coping strategy. As considerable evidence has accumulated that social support in both animal and human populations may have survival value, we sought to test the reliability of this regression model, using coping and perceived support factor values obtained at 3 months after surgery to account for concurrent follow-up NK activity in this serially assessed group of patients. It was found that the most significant variable predicting NK activity at follow-up was tumor ER concentration, with higher NK activity associated with ER- status. In addition, seeking social support as a coping strategy, as well as the perceived quality of support, also entered the model to account for a significant amount of NK activity variance (multivariate F = 5.25, p less than 0.001). If, as the literature suggests, NK activity is relevant to breast cancer control, and since ER- tumors have a worse prognosis, we suggest here that perhaps such tumors are resistant to control by NK cells because they lack the ability to attract an accumulation of effector cells to the tumor site, or because blocking factors at the site of the tumor prevent local tumor control at the site of action. The finding related to social support also replicates results from an independent sample of breast cancer patients. This finding, taken together with other evidence that this social variable is associated with longer survival in breast cancer populations, underscores the potential importance of this social support variable. Our findings also suggest one possible immunological variable involved, with potential clinical significance, for this patient population.     

Defective expression of the monocyte chemotactic protein-1 receptor CCR2 in macrophages associated with human ovarian carcinoma

Monocyte chemotactic protein-1 (MCP-1, CCL2) is an important determinant of macrophage infiltration in tumors, ovarian carcinoma in particular. MCP-1 binds the chemokine receptor CCR2. Recent results indicate that proinflammatory and anti-inflammatory signals regulate chemokine receptor expression in monocytes. The present study was designed to investigate the expression of CCR2 in tumor-associated macrophages (TAM) from ovarian cancer patients. TAM isolated from ascitic or solid ovarian carcinoma displayed defective CCR2 mRNA (Northern blot and PCR) and surface expression and did not migrate in response to MCP-1. The defect was selective for CCR2 in that CCR1 and CCR5 were expressed normally in TAM. CCR2 gene expression and chemotactic response to MCP-1 were decreased to a lesser extent in blood monocytes from cancer patients. CCR2 mRNA levels and the chemotactic response to MCP-1 were drastically reduced in fresh monocytes cultured in the presence of tumor ascites from cancer patients. Ab against TNF-alpha restored the CCR2 mRNA level in monocytes cultured in the presence of ascitic fluid. The finding of defective CCR2 expression in TAM, largely dependent on local TNF production, is consistent with previous in vitro data on down-regulation of chemokine receptors by proinflammatory molecules. Receptor inhibition may serve as a mechanism to arrest and retain recruited macrophages and to prevent chemokine scavenging by mononuclear phagocytes at sites of inflammation and tumor growth. In the presence of advanced tumors or chronic inflammation, systemic down-regulation of receptor expression by proinflammatory molecules leaking in the systemic circulation may account for defective chemotaxis and a defective capacity to mount inflammatory responses associated with advanced neoplasia.     

The role of NK cells in tumor growth assessed by induction of their suppressor cells in Japanese quails

In Japanese quails treated with chicken amniotic fluid (ChAmF) which had been previously shown to induce suppressor cells to natural killer (NK) cells, tumors appeared with shortened incubation periods after inoculation with Schmidt-Ruppin strain of Rous sarcoma virus (SR-RSV) compared with untreated quails. The tumors in ChAmF-treated quails subsequently grew in a similar pattern to those in untreated quails, whereas by challenging with a lower dose of the virus, enhanced tumor growth was observed as well as earlier onset of tumors in ChAmF-treated quails than in untreated ones. This enhancing effect on tumor growth due to suppression of NK-cell activity was transferred to normal quails with spleen cells obtained from ChAmF-treated quails, since RSV-induced tumors appeared earlier in the recipients of ChAmF-treated spleen cells than in those of untreated spleen cells. These findings show that suppression of NK-cell activity by ChAmF administration rendered quails higher susceptibility to tumor induction by SR-RSV challenge. In other words, NK-cell activity was strongly suggested to contribute to the early protection against tumor growth in the system of Rous sarcoma in Japanese quails.     

Streptococcal preparation OK-432 augments cytotoxic activity against an erythroleukemic cell line in humans

Summary The effects of OK-432, an inactivated and lyophilized preparation of a low-virulence strain of Streptococcus pyogenes, were evaluated on the cytotoxicity of lymphoid cells against a natural killer (NK)-sensitive erythroleukemic cell line K562 in patients with malignant diseases. When ten patients were treated postoperatively with daily injections of OK-432, a significant degree of augmentation in the cytotoxicity of peripheral blood lymphoid cells was evoked in all the patients, and the maximum level of cytotoxicity was on the third day after the beginning of the treatment. In spite of the successive daily administration, the level of cytotoxicity declined thereafter, but stayed higher than the pretreatment level. When OK-432 was injected IP in three patients with carcinomatous peritonitis, the cytotoxic activity of ascitic lymphoid cells was significantly enhanced. Cytotoxicity of in vitro-cultured lymphoid cells taken from peripheral blood of normal donors was also augmented by the addition of OK-432.     

Machine-learning aided in situ drug sensitivity screening predicts treatment outcomes in ovarian PDX tumors

Long-term treatment outcomes for patients with high grade ovarian cancers have not changed despite innovations in therapies. There is no recommended assay for predicting patient response to second-line therapy, thus clinicians must make treatment decisions based on each individual patient. Patient-derived xenograft (PDX) tumors have been shown to predict drug sensitivity in ovarian cancer patients, but the time frame for intraperitoneal (IP) tumor generation, expansion, and drug screening is beyond that for tumor recurrence and platinum resistance to occur, thus results do not have clinical utility. We describe a drug sensitivity screening assay using a drug delivery microdevice implanted for 24 h in subcutaneous (SQ) ovarian PDX tumors to predict treatment outcomes in matched IP PDX tumors in a clinically relevant time frame. The SQ tumor response to local microdose drug exposure was found to be predictive of the growth of matched IP tumors after multi-week systemic therapy using significantly fewer animals (10 SQ vs 206 IP). Multiplexed immunofluorescence image analysis of phenotypic tumor response combined with a machine learning classifier could predict IP treatment outcomes against three second-line cytotoxic therapies with an average AUC of 0.91.     

Identification of biologically active chemokine isoforms from ascitic fluid and elevated levels of CCL18/pulmonary and activation-regulated chemokine in ovarian carcinoma

Chemokines are important in leukocyte homeostasis, inflammation, angiogenesis, and metastasis. Here, the molecular diversity of chemokines present in ovarian carcinoma was studied by purifying the proteins to homogeneity from ascitic fluid. Biologically active intact CCL2 and processed CXCL8, CCL3, and CCL18 isoforms were recovered. CCL7 and CCL20 were also purified, but their levels were 10-fold lower compared with CXCL8, CCL2, and CCL3 and even 100-fold lower than the amounts of CCL18 isolated. In ascitic fluids from patients with ovarian carcinoma (n = 12), significantly higher levels of CXCL8 and CCL18 (2.0 versus 0.7 ng/ml (p = 0.01) and 120 versus 44 ng/ml (p = 0.0002), respectively) were detected compared with those in nonovarian carcinoma patients (n = 12). In contrast to CXCL8, CCL18 was not inducible in carcinoma cell lines. Immunostaining showed CCL18 expression in tumor-infiltrating cells with monocyte/macrophage morphology but not in the ovarian carcinoma cells. Our data demonstrate that biochemically heterogenous but biologically active forms of several chemokines are present at different concentrations in ovarian carcinoma ascitic fluid. This points to a delicate balance of chemokines in epithelial ovarian cancer and to a potentially major role for CXCL8 and CCL18 in this tumor.