At least seven animal studies investigating the effects of acupuncture in cancer or cancer-related conditions have been reported in the scientific literature.[1-5] Two of the studies were conducted in China, one of which was published in Chinese with an English abstract. One study was conducted in Japan, one in Sweden, and one in the United States. Four of the studies were ex vivo laboratory investigations using blood samples or tissues; [1-3,5] the remaining study was an animal behavioral study testing the effect of acupuncture on chemotherapy -induced nausea and vomiting. 
In a study involving normal rats, electroacupuncture (EA) (1 Hz, 5–20 V, 1-millisecond pulse width, 2 hours) applied at the point Tsu-Sanli (S36) for 2 hours daily on 3 consecutive days enhanced the cytotoxicity of splenic natural killer (NK) cells compared with a stimulation of a nonacupuncture control point in the abdominal muscle.
Another study found that NK cell activity and T-lymphocyte transformation rate were increased in a mouse model of transplanted mammary cancer compared with a control (P < .05) after eight sessions of acupuncture and moxibustion.
A study involving tumor -bearing mice (sarcoma S180) using moxibustion to warm the acupuncture point Guanyuan (CV4) once a day for 10 days found significantly increased production of erythrocytes, compared with a nontreatment control.
The fourth ex vivo study used a rat model to investigate the effect of EA on nerve growth factor (NGF), which is associated with polycystic ovary syndrome (PCOS). Women with PCOS have an increased risk of endometrial cancer and other diseases. Repeated EA treatments (12 treatments administered over 30 days) in PCO rats significantly lowered the concentrations of NGF in the ovaries, compared with untreated PCO rats.
A study of cyclophosphamide -induced emesis in a ferret behavioral model used acupuncture as an adjunct therapy in treating the emetic side effects of chemotherapy. EA at 100 Hz, 1.5 V, for 10 minutes in combination with subeffective doses of antiemetics such as ondansetron (0.04 mg/kg), droperidol (0.25 mg/kg), and metoclopramide (2.24 mg/kg) significantly reduced the total number of emetic episodes by 52%, 36%, and 73%, respectively (P < .01), in this ferret model.
A rat model has been established by injecting AT-3.1 prostate cancer cells into the tibia of the adult male Copenhagen rat, which closely mimics prostate cancer-induced bone cancer pain. The cancer-caused pain was treated with 10 Hz EA for 30 minutes a day at acupuncture point gallbladder 30 (GB30) from days 14 to 18 after cancer-cell injection. For sham control, EA needles were inserted into GB30 without stimulation. Thermal hyperalgesia, a decrease in paw withdrawal latency to a noxious thermal stimulus, and mechanical hyperalgesia, a decrease in paw withdrawal pressure threshold, were measured at baseline and 20 minutes after EA. EA significantly attenuated the hyperalgesia compared with sham control. Moreover, the EA inhibited up-regulation of preprodynorphin mRNA and dynorphin as well as interleukin-1beta (IL-1beta) and its mRNA compared with sham control. Intrathecal injection of antiserum against dynorphin A (1–17) and IL-1 receptor antagonist significantly inhibited the cancer-induced hyperalgesia. These data suggests that EA alleviates bone cancer pain at least in part by suppressing spinal dynorphin and IL-1beta expression.[7,8]
Another cutaneous cancer pain model has been established by injecting B16-BL6 melanoma cells into the plantar region of one hind paw of C57BL/6 mice. A single EA treatment showed significant analgesia on day 8 but not on day 20. EA treatments once every other day starting on day 8 showed analgesia at day 20, but EA starting on day 16 did not. The results indicate that EA exerts antihyperalgesic effects on early stage but not on late stage cutaneous cancer pain. These animal studies support the clinical use of EA in the treatment of cancer pain.
The findings of these studies suggest that acupuncture may be effective in treating cancer-related symptoms and cancer treatment–related disorders and that acupuncture may be able to activate immune functions [1-3] and regulate the autonomic nervous system.[4,5] Only one study reported a decrease in tumor volume in animals treated with acupuncture compared with control animals; however, the scientific value of this report is limited because of insufficient information about the research methodology.References
- Wu P, Cao Y, Wu J: Effects of moxa-cone moxibustion at Guanyuan on erythrocytic immunity and its regulative function in tumor-bearing mice. J Tradit Chin Med 21 (1): 68-71, 2001. [PUBMED Abstract]
- Liu LJ, Guo CJ, Jiao XM: [Effect of acupuncture on immunologic function and histopathology of transplanted mammary cancer in mice] Zhongguo Zhong Xi Yi Jie He Za Zhi 15 (10): 615-7, 1995. [PUBMED Abstract]
- Sato T, Yu Y, Guo SY, et al.: Acupuncture stimulation enhances splenic natural killer cell cytotoxicity in rats. Jpn J Physiol 46 (2): 131-6, 1996. [PUBMED Abstract]
- Lao L, Zhang G, Wong RH, et al.: The effect of electroacupuncture as an adjunct on cyclophosphamide-induced emesis in ferrets. Pharmacol Biochem Behav 74 (3): 691-9, 2003. [PUBMED Abstract]
- Stener-Victorin E, Lundeberg T, Waldenström U, et al.: Effects of electro-acupuncture on nerve growth factor and ovarian morphology in rats with experimentally induced polycystic ovaries. Biol Reprod 63 (5): 1497-503, 2000. [PUBMED Abstract]
- Zhang RX, Liu B, Wang L, et al.: Spinal glial activation in a new rat model of bone cancer pain produced by prostate cancer cell inoculation of the tibia. Pain 118 (1-2): 125-36, 2005. [PUBMED Abstract]
- Zhang RX, Li A, Liu B, et al.: Electroacupuncture attenuates bone cancer pain and inhibits spinal interleukin-1 beta expression in a rat model. Anesth Analg 105 (5): 1482-8, table of contents, 2007. [PUBMED Abstract]
- Zhang RX, Li A, Liu B, et al.: Electroacupuncture attenuates bone-cancer-induced hyperalgesia and inhibits spinal preprodynorphin expression in a rat model. Eur J Pain 12 (7): 870-8, 2008. [PUBMED Abstract]
- Mao-Ying QL, Cui KM, Liu Q, et al.: Stage-dependent analgesia of electro-acupuncture in a mouse model of cutaneous cancer pain. Eur J Pain 10 (8): 689-94, 2006. [PUBMED Abstract]