A randomized trial of cimetidine with 5-fluorouracil and folinic acid in metastatic colorectal cancer

Cimetidine repurposed as a potential immunomodulatory agent against colorectal carcinoma: A systematic review

OBJECTIVE

To determine the survival benefit and immunomodulatory effects of cimetidine pre-, peri- or post-operatively in patients with colorectal cancer (CRC).

METHODS

A systematic review was conducted using PubMed and Cochrane Library to retrieve randomized control trials (RCTs) that investigated the effects of cimetidine on survival and immunomodulation via improvement in tumor infiltrating lymphocytes (TILs) and peripheral blood lymphocytes. The review was carried out in accordance with the extended Preferred Reporting Items for Systematic Reviews and Meta-analyses.

RESULTS

Four studies with the total of 267 patients were included in this systematic review. Treatment duration varied from 5 days to 1 year. Two studies reported a significant TIL response in the resected specimens after administering cimetidine, while one RCT showed an escalation of CD3, CD4 and CD57 lymphocytes in peripheral blood compared to the baseline following cimetidine treatment (p < 0.01). Of the three trials that examined the effects of cimetidine on survival, only two studies revealed significant survival benefit while the remaining study only showed a trend towards survival benefit.

CONCLUSION

Repurposing of existing drugs like cimetidine has a potential to offer a survival benefit by acting as an immunomodulatory agent in patients undergoing curative resection for CRC. However, the heterogeneity seen in current studies and the evolvement of adjunctive therapies for CRC warrant large-scale, well-designed prospective RCTs to establish the efficacy of cimetidine in CRC.

Acid-suppressive agents and survival outcomes in patients with cancer: a systematic review and meta-analysis

BACKGROUND

Patients with cancer often receive acid-suppressive agents (ASAs) to treat common gastroesophageal reflux and peptic ulcer diseases. Our systematic review addresses the association between ASAs and survival outcomes in these patients.

METHODS

We searched MEDLINE, EMBASE, and Cochrane until December 2019, including randomized controlled trials (RCTs), quasi-RCTs, and observational studies concerning ASAs that reported progression-free survival (PFS) and/or overall survival (OS). We estimated hazard ratios (HRs) with 95% confidence intervals (CIs) using the random-effects model, and assessed heterogeneity with I² statistic.

RESULTS

We included 45,626 patients from 7 RCTs and 18 observational studies, including esophageal/gastric, colorectal, pancreatic, lung, breast, prostate, kidney, and other cancers. Five studies showed that ASAs in lung cancer patients received tyrosine kinase inhibitors (TKIs) had significantly worse PFS (HR 1.64, 95% CI 1.14 - 2.37, I² = 57%) and OS (HR 1.13, 95% CI 1.05 - 1.21, I² = 0%) than nonusers. Each of five studies found no significant association between ASAs and OS in esophageal/gastric (HR 0.91, 95% CI 0.77 - 1.09, I² = 32%) or colorectal cancer patients (HR 1.33, 95% CI 0.96- 1.85, I² = 0%). ASAs were not significantly associated with an OS in patients with kidney cancer (HR 1.04, 95% CI 0.96 - 1.13, I² = 28%).

CONCLUSIONS

Meta-analysis showed that ASAs significantly associated with an increased mortality risk in lung cancer patients treated TKIs, but not in patients with esophageal/gastric, colorectal, or kidney cancer. Until further studies confirm these results, caution should be used when administering ASAs and TKIs to patients with lung cancer.

The Effect of Perioperative Cimetidine Administration on Time to Colorectal Cancer Recurrence

BACKGROUND

Studies have reported that the perioperative use of cimetidine, a histamine type 2 receptor antagonist, in addition to chemotherapy in patients with lymph node-positive colorectal cancer (CRC) improves the survival.

STUDY QUESTION

To determine if time to CRC recurrence could be prolonged with cimetidine.

STUDY DESIGN

Cimetidine was prescribed to American Joint on Cancer Committee (AJCC) stage III CRC patients perioperatively. Tumor recurrence was defined as the time (in days) between tumor resection and CRC recurrence. Medical charts of patients diagnosed with CRC between 1996 and 2006 were reviewed. Inclusion criteria were patients with (a) AJCC stage III CRC, (b) who had undergone surgical resection of the tumor, and (c) who received chemotherapy (5-fluorouracil).

MEASURES AND OUTCOMES

AJCC stage III CRC patients who did and did not receive cimetidine as part of the treatment regimen were compared with respect to their clinical outcomes using univariate analysis and Kaplan-Meier modeling.

RESULTS

Between 1996 and 2006, 38 patients met our inclusion criteria. Twenty-six percent (10/38) received perioperative cimetidine (mean daily dose, 750 mg; mean duration, 369 days; mean total cumulative cimetidine dose, 274,070 mg/d) in addition to chemotherapy. Time to recurrence and cancer deaths were prolonged in the chemotherapy plus cimetidine group compared with the group that received chemotherapy alone (mean ± SD: 1078 ± 290 vs. 446 ± 62; P = 0.03). In addition, we found a significant positive relationship between the duration of cimetidine therapy (days) and survival duration (correlation coefficient = 0.94, P = 0.02) and time until cancer recurrence (correlation coefficient = 0.99, P = 0.04). Moreover, there was a significant positive relationship between the total cumulative cimetidine dose and survival duration (correlation coefficient = 0.92, P = 0.03).

CONCLUSIONS

Prolonged duration of cimetidine may be superior to shorter courses in prolonging recurrence of CRC and thus survival.

Analysis of surface properties of human cancer cells using derivatized beads

Standard histochemical analysis of cells and tissues generally involves procedures that utilize a relatively small number of probes such as dyes, and generally requires hours or days to process. Our laboratory has developed a novel method for histochemical surveys of cell surface properties that utilizes a large number of probes (derivatized agarose beads) and takes seconds or minutes to accomplish. In this study, 4 human cell lines (CCL-255 (LS123) human colon cancer cells that are non-tumorigenic in nude mice; CRL-1459 (CCD-18CO) human colon endothelial cells that are non-malignant; CCL-220 (COLO 320DM) human colon cancer cells that are tumorigenic in nude mice; and HTB-171 (NCI H446) human lung carcinoma cells) were tested for their ability to bind to agarose beads derivatized with 51 different molecules. There were statistically significant differences in binding of the 4 cell types to all of the 51 types of beads, but 15 types of beads showed dramatic differences in binding to one or more of the 4 cell types. For example, only HTB-171 (NCI H446) bound to p-aminophenyl-beta-D-glucopyranoside-derivatized beads and only CCL-220 (COLO 320DM) bound to L-tyrosine-derivatized beads. The specificity of cell-bead binding was examined by performing assays in the presence or absence of exogenously added compounds in hapten-type of inhibition experiments. This assay, that utilizes large numbers of novel probes, may help in the development of new libraries of surface properties of specific cell types, with differing degrees of malignancy, that at this time could not be developed by using other available technologies.

Cimetidine in colorectal cancer--are the effects immunological or adhesion-mediated?

British Journal of Cancer (2002) 86, 159–160. DOI: 10.1038/sj/bjc/6600097www.bjcancer.com

© 2002 The Cancer Research Campaign

Alleviating oxidative stress in cancer immunotherapy: a role for histamine?

Interleukin-2 is a remarkable activator of lymphocytes with anti-neoplastic properties such as T-cells or natural killer cells, but tumor regression only rarely occurs in interleukin-2-treated cancer patients. In this review, we focus on interactions between monocytes/macrophages and T-cells/natural killer-cells, and in particular the role of such interactions for the outcome of cancer immunotherapy with interleukin-2. We propose that interleukin-2 therapy should be supplemented with compounds that alleviate toxicity inflicted by monocyte/macrophage-derived reactive oxygen metabolites within and around tumors. The hypothesis is founded on data demonstrating that (i) functions of intratumoral lymphocytes in many human malignant tumors are inhibited by reactive oxygen metabolites, generated by neighboring monocytes/macrophages, (ii) interleukin-2 only weakly activates T-cells or natural killer cells in an environment of oxidative stress, and (iii) inhibitors of the formation of reactive oxygen metabolites or scavengers of reactive oxygen metabolites synergize with interleukin-2 to activate these lymphocyte subsets. We also review the preclinical background to the use of histamine dihydrochloride, an inhibitor of reactive oxygen metabolite formation in monocytes/macrophages, as a supplement to cancer immunotherapy with interleukin-2.

Histamine: a novel approach to cancer immunotherapy

The functions of intratumoral lymphocytes in many human malignant tumors are inhibited by reactive oxygen species (ROS), generated by adjacent monocytes/macrophages (MO). In vitro data suggest that immunotherapeutic cytokines such as interleukin-2 (IL-2) or interferon-alpha (IFN-alpha) only weakly activate T cells or natural killer (NK) cells in a reconstituted environment of oxidative stress and that inhibitors of the formation of ROS or scavengers of ROS synergize with IL-2 and IFN-alpha to activate T cells and NK cells. In this review, we focus on the immunoenhancing properties of histamine, a biogenic amine. Histamine inhibits ROS formation in MO via H2-receptors; thereby, histamine protects NK cells from MO-mediated inhibition and synergizes with IL-2 and IFN-alpha to induce killing of NK cell-sensitive human tumor cells in vitro. Histamine also optimizes cytokine-induced activation of several subsets of T cells by affording protection against MO-inflicted oxidative inhibition. The putative clinical benefit of histamine as an adjunct to immunotherapy with IL-2 and/or IFN-alpha is currently evaluated in clinical trials in metastatic malignant melanoma and acute myelogenous leukemia.

Immunomodulation therapy in colorectal carcinoma

There has been much progress in the understanding of the relationship between the immune system and colorectal cancer. This has led to the use of immunomodulatory therapy in the adjuvant and palliative treatment of the condition. Although attempts at the use of non-specific immunomodulation with agents such as levamisole, cimetidine, alpha interferon and Bacillus Calmette-Guerin (BCG) have not produced significant clinical benefits when tested in randomized trials in both the adjuvant setting and for metastatic disease, promising results are being obtained with more specific therapy. Edrecolomab [corrected], a murine monoclonal antibody targeting the 17-1A antigen on malignant colorectal cells has produced a reduction in relapse and mortality rates when used as adjuvant treatment following surgery for Dukes' C colon cancer. Active specific therapy with autologous tumour vaccine administered with BCG has produced similar benefits in Dukes' B cancer. Both 3H1 anti-idiotypic antibody against carcinoembryonic antigen and 105AD7 antibody to gp72 glycoprotein have demonstrated in-vitro and in-vivo immune activation against tumour. Non-randomized studies postulate prolongation of survival using these antibodies in advanced disease. These agents are all currently being tested in randomized studies powered to detect meaningful survival differences and clinical benefit. Immune therapy offers the potential of low toxicity therapy in colorectal cancer and may have a role as an adjunct to conventional chemotherapy.

Adjuvant histamine in cancer immunotherapy

Interleukin-2 (IL-2) is an effective activator of lymphocytes with anti-neoplastic properties such as T-cells or natural killer cells, and this property of IL-2 has formed the basis for its widespread used as an immunotherapeutic agent in human neoplastic disease. In recent years, IL-2 therapy for solid neoplastic diseases and hematopoietic cancers has been supplemented with histamine dihydrochloride with the aim of counteracting immunosuppressive signals from monocytes/macrophages. Here we review the preclinical basis for the use of histamine as an adjunct to IL-2 in cancer immunotherapy.

Prospective, double-blind, placebo-controlled randomized trial of cimetidine in gastric cancer. British Stomach Cancer Group

Cimetidine is thought to inhibit suppressor T-lymphocyte function and preliminary evidence from a randomized trial indicated that it might prolong survival for patients with operable and inoperable gastric cancer. The British Stomach Cancer Group conducted a randomized, double-blind, placebo-controlled trial examining the effects of cimetidine (400 mg or 800 mg twice a day) on the survival of patients with early (stages I, II and III: n = 229) and advanced (stages IVa and IVb: n = 201) gastric cancer. The primary end point was death. A total of 442 patients were randomized by 59 consultants in 39 hospitals between February 1990 and March 1995. Log-rank survival analysis was used to assess differences between the groups. Three hundred and forty patients died during the study: 166 (49%) in the cimetidine treatment groups and 174 (51%) in the placebo groups. Median survival for patients receiving cimetidine was 13 months (95% confidence interval (CI) 9-16 months) and 11 months in the placebo arm (95% CI 9-14 months). There was no significant difference in survival between the two treatment groups (P = 0.42) or between different doses of cimetidine tablets (P = 0.46). Five-year survival of those patients randomized to cimetidine was 21% compared to 18% for those patients randomized to placebo. Cimetidine at a dose of 400 mg or 800 mg twice a day does not have a significant influence on the survival of patients with gastric cancer compared to placebo.

Histamine and cytokine therapy

Interleukin-2 (IL-2) and interferon-alpha (IFN-alpha) are potent activators of natural killer (NK) cells and other anti-tumor effector cells, but the results obtained in clinical trials with these cytokines have proved disappointing in many forms of cancer. It may be that IL-2 and IFN-alpha are often not sufficiently effective because intratumoral monocytes/macrophages (MO) inhibit the cytokine-induced activation of cytotoxic effector lymphocytes such as NK-cells at the site of tumor growth. An essential part of this inhibitory signal is conveyed by MO-derived reactive oxygen species (ROS), which potently inhibit NK-cell-related functions, including the constitutive and cytokine-induced cytotoxicity against tumor cells. Histamine, a biogenic amine, inhibits ROS formation in MO; thereby, histamine synergizes with IL-2 and with IFN-alpha to induce killing of NK-cell-sensitive human tumor cells in vitro. Furthermore, treatment of tumor-bearing mice with histamine potentiates cytokine-induced killing of NK-cell-sensitive murine tumor cells in vivo. In ongoing clinical trials, histamine has been added to IL-2 or IFN-alpha in immunotherapy of human neoplastic disease. The results of two pilot trials in metastatic melanoma suggest that the addition of histamine to IL-2/IFN-alpha prolongs survival time and induces regression of tumors, such as liver melanoma, which are considered refractory to immunotherapy with IL-2 or IFN-alpha. In acute myelogenous leukemia (AML), histamine and IL-2 have been given in order to protect patients in remission against relapse of leukemic disease. The potential benefit of histamine therapy in melanoma and AML will be evaluated in randomized trials.

Pilot study--cimetidine enhances lymphocyte infiltration of human colorectal carcinoma: results of a small randomized control trial

BACKGROUND

Cimetidine preserves postoperative immune function and inhibits the growth of some cancers. In this study, the effect of cimetidine on the local immune response to colorectal carcinoma was investigated.

METHODS

Forty-two patients scheduled for elective resection of colorectal carcinoma were randomized either to receive cimetidine for 1 week perioperatively or to act as controls. A lymphocyte density of 50 cells per high-power field (approximately 50% of the tumor/tissue interface) was considered a positive response. Patient survival was determined by Kaplan-Meier life table analysis. The effects of histamine and cimetidine on normal subject lymphocyte function was determined in a mitogen-stimulated proliferation assay.

RESULTS

A positive lymphocyte response was observed in 5 of 24 control carcinoma patients (21%) and 10 of 18 cimetidine-treated carcinoma patients (56%) (P = 0.03). The presence of a lymphocyte response correlated with a better survival (P = 0.02). Histamine had an inhibitory effect on lymphocyte proliferation with a median effective dose of 5 x 10(-7) M. Cimetidine antagonized this effect with a negative logarithm of the cimetidine molar concentration required to reduce the effect of histamine in half of 6.55.

CONCLUSIONS

Histamine inhibits normal lymphocyte function, antagonized by cimetidine at a histamine type 2 receptor. Cimetidine increases lymphocyte infiltration of primary colorectal carcinoma, possibly by overcoming the immunosuppressive effects of high local histamine concentrations. The presence of a local lymphocyte response correlates with an improved 3-year survival.