Assessing the therapeutic and toxicological effects of cesium chloride following administration to nude mice bearing PC-3 or LNCaP prostate cancer xenografts

Association analyses between urinary concentrations of multiple trace elements and gastric precancerous lesions and gastric cancer in Anhui province, eastern China

Background

Limited epidemiological evidence suggests that exposure to trace elements adversely impacts the development of gastric precancerous lesions (GPL) and gastric cancer (GC). This study aimed to estimate the association of individual urinary exposure to multiple elements with GPL and GC.

Methods

A case-control investigation was conducted in Anhui Province from March 2021 to December 2022. A total of 528 subjects (randomly sampled from 1,020 patients with GPL, 200 patients with GC, and 762 normal controls) were included in our study. Urinary levels of iron (Fe), copper (Cu), zinc (Zn), nickel (Ni), strontium (Sr), and Cesium (Cs) were measured using inductively coupled plasma mass spectrometry (ICP-MS). Four different statistical approaches were employed to explore the risk of GPL and GC with mixed exposure, including multivariate logistic regression, weighted quantile regression (WQS), quantile g-computation (Qgcomp), and the Bayesian kernel machine regression (BKMR) model.

Results

The WQS model indicated that urinary exposure to a mixture of elements is positively correlated with both GPL and GC, with ORs for the mixture exposure of 1.34 (95% CI: 1.34-1.61) for GPL and 1.38 (95% CI: 1.27-1.50) for GC. The Qgcomp and BKMR models also demonstrated a statistically significant positive correlation between the mixture and both GPL and GC.

Conclusion

Considering the limitations of case-control studies, future prospective studies are warranted to elucidate the combined effects and mechanisms of trace elements exposure on human health.

The suppression of torulene and torularhodin treatment on the growth of PC-3 xenograft prostate tumors

Torulene and torularhodin are two of the principal carotenoids in Sporidiobolus pararoseus and have a similar structure to that of lycopene. The present study was to elucidate the anti-cancer activity of torulene and torularhodin in vivo with lycopene as a control. Nude mice were orally supplemented every day with a low or high dose [9 or 18 mg/kg body weight (BW)] of lycopene, torularhodin or torulene. Two weeks after the supplementation, mice were injected once with hormone-independent prostatic carcinoma PC-3 cells. When the tumor of the control group load exceeded 200 mm(3), mice were killed and the study was terminated. Compared with the controls, high-carotenoid supplementation lowered the mean number of tumors from 248.13 ± 28.74 to 50.83 ± 7.63, 70.34 ± 6.77, and 60.53 ± 6.78 mm(3) (P < 0.05, n = 8) by, respectively. Histological examination showed tumor degeneration, apoptosis and necrosis presented at the end of the experiment. Quantitative polymerase chain reaction and immunohistochemistry results showed Bcl-2 expression of the control group was higher than that of the carotenoid-treated group while the expression of Bax was lower than the carotenoid-treated group. High-carotenoid supplementation also increased the mRNA expressions of caspase-3, 8 and 9 in tumor tissues. These results show that both torulene and torularhodin supplementation inhibit the growth of prostate cancer in nude mice and suggest that such an action is associated the apoptosis of tumor cells.

Association of urinary cesium with breast cancer risk

BACKGROUND

The aim of this study is to examine the association of urinary cesium with breast cancer risk.

MATERIALS AND METHODS

We collected survey data and urine specimens from 240 women with incident invasive breast cancer before their treatment and 246 age-matched female controls between October 2009 and July 2010. Urinary concentrations of cesium were determined by inductively coupled plasma mass spectrometry. Interviews were conducted by face-to-face to obtain information on potential breast cancer risk factors. Logistic regression analysis was used to estimate the associations.

RESULTS

Creatinine-adjusted levels [median (25th, 75th) ug/g] of cesium in cases and controls were 17.6 (13.1, 24.0) and 19.3 (15.3, 25.7), respectively. After adjustment for potential risk factors, women in the second and highest tertile of cesium showed a decreased risk of breast cancer in a dose-dependent manner as compared with those in the lowest tertile [ORs and 95% CIs: 0.75 (0.46- 1.22) and 0.50 (0.30-0.82), respectively]. This decrease was more evident in women with ER positive or localized clinical stage in an exploratory stratification analysis.

CONCLUSIONS

These findings suggest that cesium may have anticancer efficacy and urinary cesium has potential as a biomarker for breast cancer risk assessment.

Rh2 or its aglycone aPPD in combination with docetaxel for treatment of prostate cancer

BACKGROUND

Docetaxel is one of the few chemotherapeutic drugs that are considered highly effective when used to treat prostate cancer patients that have relapsed and/or metastatic disease, it is therefore reasonable to expect further improvements in treatment outcomes when it is combined with other therapeutic agents active in prostate cancer. This study assesses the combination of well tolerated and orally bioavailable formulations of ginsenoside Rh2 or its aglycone aPPD with docetaxel.

METHODS

The in vitro activity of Rh2, aPPD, and docetaxel was determined in four prostate cancer cell lines: PC-3, LNCaP, DU145, and C4-2. Combinations of Rh2 or aPPD with docetaxel were assessed using the constant ratio combination design. Combination Indices (CI) and Dose Reduction Indices (DRI) were subsequently estimated using Calcusyn. In vivo efficacy studies and Immunohistochemical analyses (PC-3 model) were also evaluated.

RESULTS

In PC-3, DU145 and C4-2 prostate cancer cells combinations of Rh2 or aPPD with docetaxel were predominantly additive or synergistic. Combinations of Rh2 + docetaxel and aPPD + docetaxel caused established PC-3 tumors to regress from their initial size by 15% and 27%, respectively. Tumor cell proliferation rate (measured by Ki-67 positive cells) was significantly lower for combinations of Rh2 + docetaxel and aPPD + docetaxel, compared to animals treated with docetaxel alone.

CONCLUSIONS

Rh2 and aPPD can be combined with docetaxel to yield additive or synergistic activity in vitro and in vivo. Pending further assessment of toxicity and pharmacodynamic behavior, this study supports testing of combinations of ginsenoside Rh2 or its aglycone aPPD with docetaxel in a clinical setting.

Regression of prostate cancer xenografts by RLIP76 depletion

RLIP76 plays a central role in radiation and chemotherapy resistance through its activity as a multi-specific ATP-dependent transporter which is over-expressed in a number of types of cancers. RLIP76 appears to be necessary for cancer cell survival because both in vitro cell culture and in vivo animal tumor studies show that depletion or inhibition of RLIP76 causes selective toxicity in malignant cells. RLIP76 induces apoptosis in cancer cells through the accumulation of endogenously formed GS-E. The results of our in vivo studies demonstrate that administration of RLIP76 antibodies, siRNA or anti-sense to mice bearing xenografts of PC-3 prostate cancer cells leads to near complete regression of established subcutaneous xenografts with no apparent toxic effects. Since anti-RLIP76 IgG (which inhibit RLIP76-mediated transport), siRNA and antisense (which deplete RLIP76) showed similar tumor regressing activities, our results indicate that the inhibition of RLIP76 transport activity at the cell surface is sufficient for observed anti-tumor activity. These studies indicate that RLIP76 serves a key effector function for the survival of prostate cancer cells and that it is a valid target for cancer therapy.